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Sample records for dairy cattle herd

  1. Prevalence of Coxiella burnetii antibodies in Portuguese dairy cattle herds.

    PubMed

    Pimenta, Luís; Alegria, Nuno; Anastácio, Sofia; Sidi-Boumedine, Karim; da Silva, Gabriela; Rabiço, Ângela; Simões, João

    2015-01-01

    Q fever is an important zoonotic disease which has been recently diagnosed, mainly in sheep and goats, in Portugal. The aim of the present study was to determine the prevalence of bovine Coxiella burnetii antibodies in dairy farms from the northwest of Portugal. Bulk tank milk samples were randomly obtained, on November 2013, from 90 dairy farms and assayed using an ELISA kit. The apparent prevalence was 61.1% (95% C.I. from 50.8 to 70.5%). The proportion of negative and intermediate (inconclusive) herds was 34.5% (25.5 to 44.7%) and 4.4% (1.7 to 10.9%), respectively. In conclusion, a high level of exposure to Coxiella burnetii was observed in Portuguese dairy cattle herds, highlighting the needs to better understand the epidemiology of Q fever in Portugal by the implementation of a monitoring program based on harmonized serologic and molecular methodologies and elucidation of the infection status of the herds. PMID:25339430

  2. Exploring the value of routinely collected herd data for estimating dairy cattle welfare.

    PubMed

    de Vries, M; Bokkers, E A M; van Schaik, G; Engel, B; Dijkstra, T; de Boer, I J M

    2014-02-01

    Routine on-farm assessment of dairy cattle welfare is time consuming and, therefore, expensive. A promising strategy to assess dairy cattle welfare more efficiently is to estimate the level of animal welfare based on herd data available in national databases. Our aim was to explore the value of routine herd data (RHD) for estimating dairy cattle welfare at the herd level. From November 2009 through March 2010, 7 trained observers collected data for 41 welfare indicators in a selected sample of 183 loose-housed and 13 tethered Dutch dairy herds (herd size: 10 to 211 cows) using the Welfare Quality protocol for cattle. For the same herds, RHD relating to identification and registration, management, milk production and composition, and fertility were extracted from several national databases. The RHD were used as potential predictors for each welfare indicator in logistic regression at the herd level. Nineteen welfare indicators were excluded from the predictions, because they showed a prevalence below 5% (15 indicators), or were already listed as RHD (4 indicators). Predictions were less accurate for 7 welfare indicators, moderately accurate for 14 indicators, and highly accurate for 1 indicator. By forcing to detect almost all herds with a welfare problem (sensitivity of at least 97.5%), specificity ranged from 0 to 81%. By forcing almost no herds to be incorrectly classified as having a welfare problem (specificity of at least 97.5%), sensitivity ranged from 0 to 67%. Overall, the best-performing prediction models were those for the indicators access to at least 2 drinkers (resource based), percentage of very lean cows, cows lying outside the supposed lying area, and cows with vulvar discharge (animal based). The most frequently included predictors in final models were percentages of on-farm mortality in different lactation stages. It was concluded that, for most welfare indicators, RHD have value for estimating dairy cattle welfare. The RHD can serve as a

  3. Herd-level seroprevalence of Neospora caninum infection in dairy cattle in central and northeastern Poland.

    PubMed

    Kowalczyk, Sławomir J; Czopowicz, Michał; Weber, Corinna N; Müller, Elisabeth; Witkowski, Lucjan; Kaba, Jarosław

    2016-01-01

    A serosurvey was carried out to estimate the herd-level seroprevalence of Neospora caninum infection in cattle in central and northeastern Poland. Ninety seven dairy cattle herds from 2 provinces of Poland (Podlaskie, 47 herds and Łodzkie, 50 herds) were randomly enrolled in the study using two-stage cluster method. A simple random selection was applied within each herd to select a sample of adult cows (≥18 month-old). A total number of 734 cows were enrolled in the study. The animals were screened with a commercial competitive ELISA (Bio-X Diagnostics, Belgium). To calculate true herd-level seroprevalence test sensitivity and specificity were adjusted from an individual- to a herd-level using FreeCalc method. The true overall herd-level seroprevalence of N. caninum infection was 56.7% (95% CI: 47.5%, 65.9%). The true herd-level seroprevalence in Podlaskie was 63.3% (95% CI: 43.0%, 83.6%) and 50.5% (95% CI: 32.8%, 68.2%) in Łodzkie province and these figures did not differ significantly between the two provinces (chi2 test p = 0.238). One hundred forty three of 734 cows (19.5%) were seropositive which gave the true overall individual-level seroprevalence of 20.1% (95% CI: 17.4%, 23.2%). Percentage of seropositive cows in each herd varied from 6% to 80%. This study is the first epidemiological investigation of herd-level seroprevalence of N. caninum infection in Polish dairy cattle population. In conclusion, the result of the study confirmed previous data that N. caninum infection is widespread in the Polish cattle population and thus should be considered as a potential cause of spontaneous abortions.

  4. Time budgets of lactating dairy cattle in commercial freestall herds.

    PubMed

    Gomez, A; Cook, N B

    2010-12-01

    The aim of this study was to examine the time budgets of 205 lactating dairy cows housed in 16 freestall barns in Wisconsin and to determine the relationships between components of the time budget and herd- and cow-level fixed effects using mixed models. Using continuous video surveillance, time lying in the stall, time standing in the stall, time standing in the alleys (including drinking), time feeding, and time milking (time out of the pen for milking and transit) during a 24-h period were measured for each cow. In addition, the number of lying bouts and the mean duration of each lying bout per 24-h period were determined. Time milking varied between cows from 0.5 to 6.0 h/d, with a mean ± standard deviation of 2.7 ± 1.1h/d. Time milking was influenced significantly by pen stocking density, and time milking negatively affected time feeding, time lying, and time in the alley, but not time standing in the stall. Locomotion score, either directly or through an interaction with stall base type (a rubber crumb-filled mattress, MAT, or sand bedding, SAND), influenced pen activity. Lame cows spent less time feeding, less time in the alleys, and more time standing in the stalls in MAT herds, but not in SAND herds. The effect of lameness on lying time is complex and dependent on the time available for rest and differences in resting behavior observed between cows in MAT and SAND herds. In MAT herds, rest was characterized by a larger number of lying bouts of shorter duration than in SAND herds (mean = 14.4; confidence interval, CI: 12.4 to 16.5 vs. mean = 10.2; CI: 8.2 to 12.2 bouts per d, and mean = 1.0; CI: 0.9 to 1.1 vs. mean = 1.3, CI: 1.2 to 1.4h bout duration for MAT and SAND herds, respectively). Lameness was associated with an increase in time standing in the stall and a reduction in the mean (CI) number of lying bouts per day from 13.2 (CI: 12.3 to 14.1) bouts/d for nonlame cows to 10.9 (CI: 9.30 to 12.8) bouts/d for moderately lame cows, and an overall

  5. Seroprevalence of leptospiral infection in feline population in urban and dairy cattle herds in Mashhad, Iran

    PubMed Central

    Talebkhan Garoussi, Massoud; Mehravaran, Mohsen; Abdollahpour, Gholamreza; Khoshnegah, Javad

    2015-01-01

    The importance of cats in the Leptospira epidemiology is due to the possibility of transferring leptospirosis to wild and domesticated animals. The purpose of this survey was to determine the prevalence of Leptospira infection in shorthair cats in different location of Mashhad, Iran. Totally, 147 blood samples were taken from 42 (28.57%), 52 (35.37%) and 53 (36.05%) households, stray and cats which lived in industrial dairy cattle herds of Mashhad, Iran, respectively. Sera were tested with seven live Leptospira antigens using microscopic agglutination test (MAT). Sera with 50.00% agglutination at the dilution of ≥ 1/100 were considered as positive samples. Agglutination at dilutions of < 1/100 considered as suspected to Leptospira infection. Overall, 19 (12.92%) out of 147 cats showed reaction in MAT. The seroprevalence at a titer ≥ 1:100 and < 1:100 were 10 (6.80%) and 9 (6.12%), respectively. Serum samples showed positive reaction against Leptospira intterogans hardjo (no = 10; 52.63%), pomona (no = 5; 26.31%) and icterohaemorrhagiae (no = 4; 21.05%). Eight cats (42.10%) belong to dairy cattle herds had the most infection only by L. I. hardjo with 1:200 titer. There were no significant differences among the weight‚ age and sex of infected cats. However, there were significant differences between the infected cats in dairy cattle herds and the cats in the urban area (p < 0.05). It is concluded that cats can be infected by Leptospira spp. especially in commercial dairy cattle herds. Cats can be considered as a sanitation hazards in the area for this zoonotic disease. PMID:26973765

  6. Spread of Coxiella burnetii between dairy cattle herds in an enzootic region: modelling contributions of airborne transmission and trade.

    PubMed

    Pandit, Pranav; Hoch, Thierry; Ezanno, Pauline; Beaudeau, François; Vergu, Elisabeta

    2016-04-05

    Q fever, a worldwide zoonotic disease caused by Coxiella burnetii, is a looming concern for livestock and public health. Epidemiological features of inter-herd transmission of C. burnetii in cattle herds by wind and trade of cows are poorly understood. We present a novel dynamic spatial model describing the inter-herd regional spread of C. burnetii in dairy cattle herds, quantifying the ability of airborne transmission and animal trade in C. burnetii propagation in an enzootic region. Among all the new herd infections, 92% were attributed to airborne transmission and the rest to cattle trade. Infections acquired following airborne transmission were shown to cause relatively small and ephemeral intra-herd outbreaks. On the contrary, disease-free herds purchasing an infectious cow experienced significantly higher intra-herd prevalence. The results also indicated that, for short duration, both transmission routes were independent from each other without any synergistic effect. The model outputs applied to the Finistère department in western France showed satisfactory sensitivity (0.71) and specificity (0.80) in predicting herd infection statuses at the end of one year in a neighbourhood of 3 km around expected incident herds, when compared with data. The model developed here thus provides important insights into the spread of C. burnetii between dairy cattle herds and paves the way for implementation and assessment of control strategies.

  7. Spread of Coxiella burnetii between dairy cattle herds in an enzootic region: modelling contributions of airborne transmission and trade.

    PubMed

    Pandit, Pranav; Hoch, Thierry; Ezanno, Pauline; Beaudeau, François; Vergu, Elisabeta

    2016-01-01

    Q fever, a worldwide zoonotic disease caused by Coxiella burnetii, is a looming concern for livestock and public health. Epidemiological features of inter-herd transmission of C. burnetii in cattle herds by wind and trade of cows are poorly understood. We present a novel dynamic spatial model describing the inter-herd regional spread of C. burnetii in dairy cattle herds, quantifying the ability of airborne transmission and animal trade in C. burnetii propagation in an enzootic region. Among all the new herd infections, 92% were attributed to airborne transmission and the rest to cattle trade. Infections acquired following airborne transmission were shown to cause relatively small and ephemeral intra-herd outbreaks. On the contrary, disease-free herds purchasing an infectious cow experienced significantly higher intra-herd prevalence. The results also indicated that, for short duration, both transmission routes were independent from each other without any synergistic effect. The model outputs applied to the Finistère department in western France showed satisfactory sensitivity (0.71) and specificity (0.80) in predicting herd infection statuses at the end of one year in a neighbourhood of 3 km around expected incident herds, when compared with data. The model developed here thus provides important insights into the spread of C. burnetii between dairy cattle herds and paves the way for implementation and assessment of control strategies. PMID:27048416

  8. Bovine viral diarrhea virus (BVDV) infection in dairy cattle herds in northeast Thailand.

    PubMed

    Nilnont, Theerakul; Aiumlamai, Suneerat; Kanistanont, Kwankate; Inchaisri, Chaidate; Kampa, Jaruwan

    2016-08-01

    Bovine viral diarrhea virus causes a wide range of clinical manifestation with subsequent economic losses in dairy production worldwide. Our study of a population of dairy cattle in Thailand based on 933 bulk tank milk samples from nine public milk collection centers aimed to monitor infective status and to evaluate the effect of the infection in cows as well as to examine the reproductive performance of heifers to provide effective recommendations for disease control in Thailand. The results showed a moderate antibody-positive prevalence in the herd (62.5 %), with the proportion of class-3 herd, actively infected stage, being 17.3 %. Fourteen persistently infected (PI) animals were identified among 1196 young animals from the class-3 herds. Most of the identified PI animals, 11/14, were born in one sub-area where bovine viral diarrhea virus (BVDV) investigation has not been performed to date. With respect to reproductive performance, class-3 herds also showed higher median values of reproductive indices than those of class-0 herds. Cows and heifers in class-3 herds had higher odds ratio of calving interval (CI) and age at first service (AFS) above the median, respectively, compared to class-0 herds (OR = 1.29; P = 0.02 and OR = 1.63; P = 0.02). Our study showed that PI animals were still in the area that was previously studied. Furthermore, a newly studied area had a high prevalence of BVDV infection and the infection affected the reproductive performance of cows and heifers. Although 37.5 % of the population was free of BVDV, the lack of official disease prevention and less awareness of herd biosecurity may have resulted in continuing viral spread and silent economic losses have potentially occurred due to BVDV. We found that BVDV is still circulating in the region and, hence, a national control program is required.

  9. Bovine viral diarrhea virus (BVDV) infection in dairy cattle herds in northeast Thailand.

    PubMed

    Nilnont, Theerakul; Aiumlamai, Suneerat; Kanistanont, Kwankate; Inchaisri, Chaidate; Kampa, Jaruwan

    2016-08-01

    Bovine viral diarrhea virus causes a wide range of clinical manifestation with subsequent economic losses in dairy production worldwide. Our study of a population of dairy cattle in Thailand based on 933 bulk tank milk samples from nine public milk collection centers aimed to monitor infective status and to evaluate the effect of the infection in cows as well as to examine the reproductive performance of heifers to provide effective recommendations for disease control in Thailand. The results showed a moderate antibody-positive prevalence in the herd (62.5 %), with the proportion of class-3 herd, actively infected stage, being 17.3 %. Fourteen persistently infected (PI) animals were identified among 1196 young animals from the class-3 herds. Most of the identified PI animals, 11/14, were born in one sub-area where bovine viral diarrhea virus (BVDV) investigation has not been performed to date. With respect to reproductive performance, class-3 herds also showed higher median values of reproductive indices than those of class-0 herds. Cows and heifers in class-3 herds had higher odds ratio of calving interval (CI) and age at first service (AFS) above the median, respectively, compared to class-0 herds (OR = 1.29; P = 0.02 and OR = 1.63; P = 0.02). Our study showed that PI animals were still in the area that was previously studied. Furthermore, a newly studied area had a high prevalence of BVDV infection and the infection affected the reproductive performance of cows and heifers. Although 37.5 % of the population was free of BVDV, the lack of official disease prevention and less awareness of herd biosecurity may have resulted in continuing viral spread and silent economic losses have potentially occurred due to BVDV. We found that BVDV is still circulating in the region and, hence, a national control program is required. PMID:27154218

  10. Vaccination using phase I vaccine is effective to control Coxiella burnetii shedding in infected dairy cattle herds.

    PubMed

    Taurel, Anne-Frieda; Guatteo, Raphaël; Lehebel, Anne; Joly, Alain; Beaudeau, François

    2014-01-01

    The effectiveness of the vaccination of dairy cows combined or not with antibiotics (i.e. oxytetracycline) to control Coxiella burnetii (Cb) shedding at herd level was investigated in 77 Q fever clinically affected herds. In addition to nulliparous heifers' vaccination, one out of the four following medical strategies was randomly assigned to dairy cows in each herd: vaccination (using a phase I vaccine) alone, vaccination combined with oxytetracycline, oxytetracycline alone or nothing. Their effectiveness to reduce Cb load in quarterly samples of bulk tank milk (BTM) and of pooled milk of primiparous (MP) was assessed through logistic hierarchical models. A significant reduction in Cb load was observed in herds where the vaccination of ≥80% of dairy cows was implemented; whereas the use of antibiotics was uneffective. Our findings support the interest of a whole vaccination strategy and provide evidence for decreasing the use of antibiotics in dairy cattle herds.

  11. Herd factors influencing oocyst production of Eimeria and Cryptosporidium in Estonian dairy cattle.

    PubMed

    Lassen, Brian; Viltrop, Arvo; Järvis, Toivo

    2009-10-01

    Cryptosporidium and Eimeria are intestinal parasites which are sensitive to the surroundings, behaviour and well-being of their host. In the present study, a range of factors related to farm management systems, environment, housing and herd characteristics were investigated with regard to alterations in oocyst excretion in cattle, using a mixed-effects model. Information and samples for three age categories were obtained from 45 Estonian dairy farms, located in 15 counties. Leaving the calf with the mother after birth reduced the risk of shedding higher levels of Cryptosporidium (OR = 0.20) and Eimeria (OR = 0.68) oocysts in all animals. The calves younger than 3 months kept on farms housing at least 150 animals had less risk (OR = 0.39) of producing higher numbers of Cryptosporidium oocysts. A somewhat lower infection level was observed in 3- to 12-month-old animals housed in separate buildings (OR = 0.64). The chance of shedding higher levels of Eimeria doubled (OR = 2.27) in cattle older than a year in case a vacancy period was used before replacing animals in pens and tripled (OR = 2.94) when the relative humidity exceeded 75% in the cowshed. Winter reduced the odds (OR = 0.25) of shedding Eimeria oocysts in the oldest animals compared to the fall season. Simple changes in handling and housing of cattle may produce a positive effect on controlling coccidian infections in Estonian dairy herds.

  12. The validity of a monitoring system based on routinely collected dairy cattle health data relative to a standardized herd check.

    PubMed

    Brouwer, H; Stegeman, J A; Straatsma, J W; Hooijer, G A; Schaik, G van

    2015-11-01

    Dairy cattle health is often assessed during farm visits. However, farm visits are time consuming and cattle health is assessed at only one point in time. Moreover, farm visits are poorly comparable and/or repeatable when inspection is carried out by many different professionals. Many countries register cattle health parameters such as bulk milk somatic cell count (BMSCC) and mortality in central databases. A great advantage of such routinely available data is that they are uniformly gathered and registered throughout time. This makes comparison between dairy cattle herds possible and could result in opportunities to develop reliable tools for assessing cattle health based on routinely available data. In 2005, a monitoring system for the assessment of cattle health in Dutch dairy herds based on routinely available data was developed. This system had to serve as an alternative for the compulsory quarterly farm visits, which were implemented in 2002. However, before implementation of the alternative system for dairy cows, the validity of the data-based monitoring system and the compulsory quarterly visits relative to the real health status of the herd should be known. The aim of this study was to assess the validity of the data-based monitoring system and the compulsory quarterly visits relative to a standardized herd check for detecting dairy herds with health problems. The results showed that routinely available data can be used to develop an effective screening instrument for detecting herds with poor cattle health. Routinely available data such as cattle mortality and BMSCC that were used in this study had a significant association with animal-based measurements such as the general health impression of the dairy cows (including e.g. rumen fill and body condition). Our study supports the view that cattle health parameters based on routinely available data can serve as a tool for detecting herds with a poor cattle health status which can reduce the number of

  13. Invited review: associations between variables of routine herd data and dairy cattle welfare indicators.

    PubMed

    de Vries, M; Bokkers, E A M; Dijkstra, T; van Schaik, G; de Boer, I J M

    2011-07-01

    As farm animal welfare is high on the political and societal agendas of many countries, considerable pressure exists to establish audit programs in which farm animal welfare is routinely monitored. On-farm assessment of animal welfare, however, is time-consuming and costly. A promising strategy to monitor animal welfare more efficiently is to first estimate the level of animal welfare on a farm based on routine herd data that are available in national databases. It is not currently known which variables of routine herd data (VRHD) are associated with dairy cattle welfare indicators (WI). Our aim was to identify VRHD that are associated with WI in a literature review. The 27 VRHD used in this review included the main types of data that are currently collected in national herd databases of developed countries, and related to identification and registration, management, milk production, and reproduction of dairy herds. The 34 WI used in this review were based on the Welfare Quality Assessment Protocol for Cattle. The search yielded associations in 146 studies. Twenty-three VRHD were associated with 16 WI. The VRHD that related to milk yield, culling, and reproduction were associated with the largest number of WI. Few associations were found for WI that referred to behavioral aspects of animal welfare, nonspecific disease symptoms, or resources-based indicators. For 18 WI, associations with VRHD were not significant (n=5 WI) or no studies were found that investigated associations with VRHD (n=13 WI). It was concluded that many VRHD have potential to estimate the level of animal welfare on dairy farms. As strengths of associations were not considered in this review, however, the true value of these VRHD should be further explored. Moreover, associations found at the animal level and in an experimental setting might not appear at the farm level and in common practice and should be investigated. Cross-sectional studies using integrated welfare scores at the farm level are

  14. Optimizing productivity, herd structure, environmental performance, and profitability of dairy cattle herds.

    PubMed

    Liang, D; Cabrera, V E

    2015-04-01

    This study used the Integrated Farm System Model to simulate the whole farm performance of a representative Wisconsin dairy farm and predict its economic and environmental outputs based on 25 yr of daily local weather data (1986 to 2010). The studied farm, located in southern Wisconsin, had 100 milking cows and 100 ha of cropland with no replacement heifers kept on the farm. Sensitivity analyses were conducted to test the effect of management strategies on energy-corrected milk production (ECM; 4.0% fat and 3.5% protein), net return to management, and greenhouse gas (GHG; including biogenic CO2) emission. The management strategies included (1) target milk production, for which the model optimized available resources to attain, and (2) herd structure, represented by the percentage of first-lactation cows. Weather conditions affected the outputs by changing the farm quantity and the quality of produced feed resources. As expected, when target milk production increased, the ECM increased positively and linearly to a certain level, and then it increased nonlinearly at a decreasing rate, constrained by available feed nutrients. Thereafter, the ECM reached the maximum potential milk production and remained flat regardless of higher target milk production input. Greenhouse gas emissions decreased between 3.4 and 7.3% at different first-lactation cow percentages. As the first-lactation cow percent increased from 15 to 45% in 5% intervals, GHG increased between 9.4 and 11.3% at different levels of target milk production. A high percentage of first-lactation cows reduced the maximum potential milk production. Net return to management had a similar changing trend as ECM. As the target milk production increased from 9,979 to 11,793 kg, the net return to management increased between 31 and 46% at different first-lactation cow percentages. Results revealed a win-win situation when increasing milk production or improving herd structure, which concurrently increased farm net

  15. Optimizing productivity, herd structure, environmental performance, and profitability of dairy cattle herds.

    PubMed

    Liang, D; Cabrera, V E

    2015-04-01

    This study used the Integrated Farm System Model to simulate the whole farm performance of a representative Wisconsin dairy farm and predict its economic and environmental outputs based on 25 yr of daily local weather data (1986 to 2010). The studied farm, located in southern Wisconsin, had 100 milking cows and 100 ha of cropland with no replacement heifers kept on the farm. Sensitivity analyses were conducted to test the effect of management strategies on energy-corrected milk production (ECM; 4.0% fat and 3.5% protein), net return to management, and greenhouse gas (GHG; including biogenic CO2) emission. The management strategies included (1) target milk production, for which the model optimized available resources to attain, and (2) herd structure, represented by the percentage of first-lactation cows. Weather conditions affected the outputs by changing the farm quantity and the quality of produced feed resources. As expected, when target milk production increased, the ECM increased positively and linearly to a certain level, and then it increased nonlinearly at a decreasing rate, constrained by available feed nutrients. Thereafter, the ECM reached the maximum potential milk production and remained flat regardless of higher target milk production input. Greenhouse gas emissions decreased between 3.4 and 7.3% at different first-lactation cow percentages. As the first-lactation cow percent increased from 15 to 45% in 5% intervals, GHG increased between 9.4 and 11.3% at different levels of target milk production. A high percentage of first-lactation cows reduced the maximum potential milk production. Net return to management had a similar changing trend as ECM. As the target milk production increased from 9,979 to 11,793 kg, the net return to management increased between 31 and 46% at different first-lactation cow percentages. Results revealed a win-win situation when increasing milk production or improving herd structure, which concurrently increased farm net

  16. Q fever infection in dairy cattle herds: increased risk with high wind speed and low precipitation.

    PubMed

    Nusinovici, S; Frössling, J; Widgren, S; Beaudeau, F; Lindberg, A

    2015-11-01

    Ruminants are considered the main reservoir for transmission of Coxiella burnetii (Cb) to humans. The implementation of effective control measures against Cb in ruminants requires knowledge about potential risk factors. The objectives of this study were (i) to describe the spatial distribution of Q fever-infected dairy cattle herds in Sweden, (ii) to quantify the respective contributions of wind and animal movements on the risk of infection, while accounting for other sources of variation, and (iii) to investigate the possible protective effect of precipitation. A total of 1537 bulk milk samples were collected and tested for presence of Cb antibodies. The prevalence of test-positive herds was higher in the south of Sweden. For herds located in areas with high wind speed, open landscape, high animal densities and high temperature, the risk of being infected reached very high values. Because these factors are difficult to control, vaccination could be an appropriate control measure in these areas. Finally, the cumulated precipitation over 1 year was identified as a protective factor.

  17. Salmonella Dublin faecal excretion probabilities in cattle with different temporal antibody profiles in 14 endemically infected dairy herds.

    PubMed

    Nielsen, L R

    2013-09-01

    This longitudinal field study investigated the hypothesis that persistently high antibody levels indicate a high risk of Salmonella Dublin shedding in animals in 14 endemically infected dairy herds. A hierarchical multivariable logistic regression was used to analyse 6614 paired faecal cultures and four types of temporal antibody profiles from cattle aged ≥180 days. Age and repeated measurements on animals nested within herds were taken into account. Overall, the prevalence of faecal shedders was low (0·3% and 2·8% in the lowest and highest risk groups, respectively). An important predictor of faecal shedding was young age. There was a significant, but modest increase in risk in cattle with persistently high or recently increased antibody levels, but no difference between these two groups. Contrary to previous recommendations, the detection of carriers by the use of repeated antibody testing is not likely to be a plausible control option in most Salmonella Dublin-infected dairy herds.

  18. Prevalence and risk factors for Coxiella burnetii (Q fever) in Dutch dairy cattle herds based on bulk tank milk testing.

    PubMed

    van Engelen, E; Schotten, N; Schimmer, B; Hautvast, J L A; van Schaik, G; van Duijnhoven, Y T H P

    2014-11-01

    Despite cattle herds can harbor Coxiella burnetii, risk factors for C. burnetii presence in dairy cattle herds are largely unknown. Therefore, C. burnetii herd prevalence and risk factors for bulk tank milk (BTM) positivity were investigated. In this cross-sectional study, a questionnaire was filled out by the farmer and BTM from 301 farms was tested by ELISA for presence of C. burnetii antibodies and PCR for presence of C. burnetii DNA. Risk factors were identified by univariable and multivariable logistic regression analyses. Antibodies to C. burnetii were detected in 81.6% (CI: 77.2-85.9) and C. burnetii DNA in 18.8% (CI: 14.4-23.1) of the BTM samples. Herd size (OR=1.1 per 10 cows), cleaning the bedding of the cubicles at most every other day (OR=2.8) and purchase of cattle from at least two addresses (OR=3.1) showed a significant and positive association with ELISA positivity and use of an automatic milking system a negative association (OR=0.3). Risk factors for PCR positivity were purchase of cattle from at least two delivery addresses (OR=3.2), presence of cows with ticks (OR=2.0), use of an automatic milking system (OR=0.2) and presence of goats or sheep on the farm (OR=0.4). Biosecurity and general hygiene seem associated with introduction and spread of C. burnetii in dairy herds. PMID:25239684

  19. Relative associations of cattle movements, local spread, and biosecurity with bovine viral diarrhoea virus (BVDV) seropositivity in beef and dairy herds.

    PubMed

    Gates, M C; Woolhouse, M E J; Gunn, G J; Humphry, R W

    2013-11-01

    The success of bovine viral diarrhoea virus (BVDV) eradication campaigns can be undermined by spread through local transmission pathways and poor farmer compliance with biosecurity recommendations. This work combines recent survey data with cattle movement data to explore the issues likely to impact on the success of BVDV control in Scotland. In this analysis, data from 249 beef suckler herds and 185 dairy herds in Scotland were studied retrospectively to determine the relative influence of cattle movements, local spread, and biosecurity on BVDV seropositivity. Multivariable logistic regression models revealed that cattle movement risk factors had approximately 3 times greater explanatory power than risk factors for local spread amongst beef suckler herds, but approximately the same explanatory power as risk factors for local spread amongst dairy herds. These findings are most likely related to differences in cattle husbandry practices and suggest that where financial prioritization is required, focusing on reducing movement-based risk is likely to be of greatest benefit when applied to beef suckler herds. The reported use of biosecurity measures such as purchasing cattle from BVDV accredited herds only, performing diagnostic screening at the time of sale, implementing isolation periods for purchased cattle, and installing double fencing on shared field boundaries had minimal impact on the risk of beef or dairy herds being seropositive for BVDV. Only 28% of beef farmers and 24% of dairy farmers with seropositive herds recognized that their cattle were affected by BVDV and those that did perceive a problem were no less likely to sell animals as replacement breeding stock and no more likely to implement biosecurity measures against local spread than farmers with no perceived problems. In relation to the current legislative framework for BVDV control in Scotland, these findings emphasize the importance of requiring infected herds take appropriate biosecurity measures

  20. Gross margin losses due to Salmonella Dublin infection in Danish dairy cattle herds estimated by simulation modelling.

    PubMed

    Nielsen, T D; Kudahl, A B; Østergaard, S; Nielsen, L R

    2013-08-01

    Salmonella Dublin affects production and animal health in cattle herds. The objective of this study was to quantify the gross margin (GM) losses following introduction and spread of S. Dublin within dairy herds. The GM losses were estimated using an age-structured stochastic, mechanistic and dynamic simulation model. The model incorporated six age groups (neonatal, pre-weaned calves, weaned calves, growing heifers, breeding heifers and cows) and five infection stages (susceptible, acutely infected, carrier, super shedder and resistant). The effects of introducing one S. Dublin infectious heifer were estimated through 1000 simulation iterations for 12 scenarios. These 12 scenarios were combinations of three herd sizes (85, 200 and 400 cows) and four management levels (very good, good, poor and very poor). Input parameters for effects of S. Dublin on production and animal health were based on literature and calibrations to mimic real life observations. Mean annual GMs per cow stall were compared between herds experiencing within-herd spread of S. Dublin and non-infected reference herds over a 10-year period. The estimated GM losses were largest in the first year after infection, and increased with poorer management and herd size, e.g. average annual GM losses were estimated to 49 euros per stall for the first year after infection, and to 8 euros per stall annually averaged over the 10 years after herd infection for a 200 cow stall herd with very good management. In contrast, a 200 cow stall herd with very poor management lost on average 326 euros per stall during the first year, and 188 euros per stall annually averaged over the 10-year period following introduction of infection. The GM losses arose from both direct losses such as reduced milk yield, dead animals, treatment costs and abortions as well as indirect losses such as reduced income from sold heifers and calves, and lower milk yield of replacement animals. Through sensitivity analyses it was found that the

  1. Schmallenberg virus antibody development and decline in a naturally infected dairy cattle herd in Germany, 2011-2014.

    PubMed

    Wernike, Kerstin; Holsteg, Mark; Sasserath, Michael; Beer, Martin

    2015-12-31

    In late 2011, the novel insect-transmitted orthobunyavirus Schmallenberg virus (SBV) emerged in Central Europe. Since that year, a dairy cattle herd kept in the German region in which the virus was initially detected was continuously monitored. In order to evaluate the development of the within-herd seroprevalence, but also to assess the long-term persistence of antibodies against SBV in individual animals, blood samples of all cows older than 24 months were taken yearly after the respective vector season and serologically analyzed. In December 2011, in 74% of the tested animals SBV-specific antibodies were detectable. Additional scattered seroconversions were observed between the 2011 and 2012 vector seasons, thereafter all seronegative animals remained negative. Until December 2014, the intra-herd seroprevalence decreased to 58%. A total of 122 cows infected presumable in autumn 2011 were sampled every year, 9 of them became seronegative until December 2014. Consequently, though SBV-specific antibodies were detected in about 90% of the monitored animals for more than three years, a lifelong antibody-based immunity is not expected in every animal. The loss of anti-SBV antibodies in individual animals combined with the missing infection of young stock results in a declining herd seroprevalence and increases the risk of a renewed virus circulation to a greater extent within the next years.

  2. Dairy Herd Health.

    ERIC Educational Resources Information Center

    Wolanyk, Alison M.; Bishop, Natalie

    This monograph, designed to help secondary students recognize symptoms of major dairy cattle diseases, stresses the need for preventative management practices and cooperation between the dairy farmer and the veterinarian. The first of three parts, The Healthy Animal, is divided into five units: body parts, vital signs, excretions, behavior, and…

  3. Invited review: modeling within-herd transmission of Mycobacterium avium subspecies paratuberculosis in dairy cattle: a review.

    PubMed

    Marcé, C; Ezanno, P; Weber, M F; Seegers, H; Pfeiffer, D U; Fourichon, C

    2010-10-01

    Epidemiological models have been developed to test hypotheses on Mycobacterium avium ssp. paratuberculosis (Map) transmission in a herd, and to compare different paratuberculosis control strategies and alternatives for certification-and-surveillance schemes. The models are simplified representations of existing biological processes tailored to the questions they are intended to answer. Such models depend on available knowledge about the underlying processes, notably in relation to pathogen transmission. All decisions relating to integration of specific aspects of the herd structure and transmission mechanisms as well as modeling objective will influence model behavior and simulation results. This paper examines assumptions on pathogen transmission and risk mitigation represented in 8 epidemiological models of within-herd Map transmission in dairy cattle. We describe available models' structure and examine them in the context of current knowledge about host infection and pathogen transmission pathways. We investigate how population structure and herd management are modeled with regard to their influence on contact structure and pathogen transmission. We show that assumptions about routes of transmission and their contribution within a herd vary greatly among models. Gaps of knowledge that are pivotal to defining transmission equations and parameters, such as variation of susceptibility with age and variability of pattern of shedding, are identified. Quantitative estimates of this incomplete information should be targeted by future research. Existing models could be improved by considering indirect transmission via the environment taking account of Map survival and contact structure between animals in a herd, and by including calf-to-calf transmission, which has recently been proven as being important.

  4. Cattle rabies vaccination--A longitudinal study of rabies antibody titres in an Israeli dairy herd.

    PubMed

    Yakobson, Boris; Taylor, Nick; Dveres, Nelli; Rozenblut, Shira; Tov, Boris Even; Markos, Majid; Gallon, Nadav; Homer, David; Maki, Joanne

    2015-09-01

    In contrast to many regions of the world where rabies is endemic in terrestrial wildlife species, wildlife rabies has been controlled in Israel by oral rabies vaccination programs, but canine rabies is re-emerging in the northern area of the Golan Heights. From 2009 to 2014 there were 208 animal rabies cases in Israel; 96 (46%) were considered introduced primary cases in dogs, triggering 112 secondary cases. One third (37/112) of the secondary cases were in cattle. Rabies vaccination is voluntary for cattle in Israel, except those on public exhibit. Rabies vaccination schedules for cattle vary based on farm practices and perception of risk. In this study 59 cattle from a dairy farm which routinely vaccinates against rabies were assigned into six groups according to age and vaccination histories. Four groups contained adult cows which had received one previous rabies vaccination, one group of adults had received two previous vaccinations, and one group was unvaccinated calves. Serum samples were collected and the cows were vaccinated with a commercial rabies vaccine. Sera were again collected 39 days later and the calf group re-vaccinated and re-sampled 18 days later. Sera were analyzed for the presence of rabies virus neutralizing antibodies using the rapid immunofluorescent antibody test. Cattle with antibody titres ≥ 0.5 IU/ml were considered to be protected against rabies. Twenty-six of 27 adult cattle (96%) vaccinated once at less than five months old did not have protective titres. Sixty percent (6/10) cattle vaccinated once at around six months of age did have adequate titres. Cattle previously vaccinated twice (n=10; 100%) with an 18 month interval between inoculations, had protective titres and protective antibody titres following booster vaccination (n=51; 100%). The anamnestic response of cattle to a killed rabies vaccine was not affected by the time interval between vaccinations, which ranged from 12 to 36 months. These results suggest that calves from

  5. Seroprevalence and risk factors associated with bovine viral diarrhea virus (BVDV) infection in non-vaccinated dairy and dual purpose cattle herds in Ecuador.

    PubMed

    Saa, Luis Rodrigo; Perea, Anselmo; García-Bocanegra, Ignacio; Arenas, Antonio José; Jara, Diego Vinicio; Ramos, Raul; Carbonero, Alfonso

    2012-03-01

    A cross-sectional study was carried out to determine the seroprevalence and risk factors associated with Bovine viral diarrhea virus (BVDV) infection in non-vaccinated dairy and dual-purpose cattle herds from Ecuador. A total of 2,367 serum samples from 346 herds were collected from June 2008 through February 2009. A questionnaire, which included variables related to cattle, health, management measures, and the environment, was filled out in each herd. A commercial indirect enzyme-linked immunosorbent assay test was used to determine the seropositivity. A logistic regression model was used to determine risk factors at herd level. The individual seroprevalence for BVDV in non-vaccinated herds in Ecuador was 36.2% (857/2,367; CI(95%), 34.3-38.1%). The herd prevalence was 74% (256/346; CI(95%), 69.4-78.6%) and the intra-herd prevalence ranged between 11.1% and 100% (mean = 51.6%). The logistic regression model showed that the density of cattle farms in the area (more than 70%; OR, 1.94; CI(95%), 1.21-3.2) and the altitude (higher than 2,338 m above sea level; 2.33; CI(95%), 1.4-3.9) are potential risk factors associated with BVDV infection.

  6. Description and factors of variation of the overall health score in French dairy cattle herds using the Welfare Quality(®) assessment protocol.

    PubMed

    Coignard, M; Guatteo, R; Veissier, I; de Boyer des Roches, A; Mounier, L; Lehébel, A; Bareille, N

    2013-11-01

    Extensive information is available in the literature on the specific risk factors of the main health disorders afflicting dairy cattle herds. However, it remains difficult to manage a herd's overall health because measures to control one risk factor can exacerbate the risk of another disease. To achieve and maintain good overall herd health, livestock systems and management practices need to simultaneously take into account all of the main health disorders. We aimed to identify the characteristics of systems and practices conducive to good herd health using the Welfare Quality(®) assessment protocol for cattle. This protocol allows an assessment of the level of health and welfare at the herd level according to the opinion of a selected group of 13 experts from animal sciences. Our objectives were to (i) describe the distribution of dairy herds' health scores in a representative sample of French dairy cattle herds, and (ii) to investigate systems (housing system, milking system, herd size, breed, farm location) and management practices associated with variations of the overall health score of dairy herds. This protocol was carried out on 130 farms between December 2010 and March 2011. A multivariable analysis of variance (ANOVA) was performed to investigate the factors of variation of the overall health score at the herd level. The overall health scores of the farms in the sample were classified as moderate for the vast majority of farms (95.4%) (mainly due to subclinical mastitis, dystocia and pain induced by disbudding/dehorning) and varied little between farms. Some livestock systems were associated with a higher overall health score: straw yards and milking parlors (P<0.0001), highland vs. lowland locations (P=0.013), Montbeliarde rather than Holstein breeds (P=0.006). Some management practices also were associated with a higher level of health: medium herd average parity (P=0.03), low proportion of dirty cows (P=0.002) and low proportion of cows with abnormal

  7. Production effects related to mastitis and mastitis economics in dairy cattle herds.

    PubMed

    Seegers, Henri; Fourichon, Christine; Beaudeau, François

    2003-01-01

    Mastitis is the most prevalent production disease in dairy herds world-wide and is responsible for several production effects. Milk yield and composition can be affected by a more or less severe short-term depression and, in case of no cure, by a long-acting effect, and, sometimes, an overlapping effect to the next lactation. Summary values in the literature for losses of milk production were proposed at 375 kg for a clinical case (5% at the lactation level) and at 0.5 kg per 2-fold increase of crude SCC of a cow. Due to the withdrawal period after treatment, composition changes in milk can almost be neglected in economic calculations. Lethality rate for clinical mastitis is very low on the average, while anticipated culling occurs more frequently after clinical and subclinical mastitis (relative risk between 1.5 and 5.0). The economics of mastitis needs to be addressed at the farm level and, per se, depends on local and regional epidemiological, managerial and economic conditions. To assess the direct economic impact of mastitis, costs (i.e. extra resource use) and losses (i.e. reduced revenues) have to be aggregated. To support decision making for udder health control, it is necessary to use a marginal approach, based on the comparison of the losses avoided and the additional costs of modified plans, compared to the existing ones.

  8. Low body condition predisposes cattle to lameness: An 8-year study of one dairy herd.

    PubMed

    Randall, L V; Green, M J; Chagunda, M G G; Mason, C; Archer, S C; Green, L E; Huxley, J N

    2015-06-01

    Lameness in dairy cows is a multifactorial and progressive disease with complex interactions between risk factors contributing to its occurrence. Detailed records were obtained from one United Kingdom dairy herd over an 8-yr period. Weekly locomotion scores were used to classify cows as not lame (score 1 to 2), mildly lame (score 3) and severely lame (score 4 to 5). These outcomes were used to investigate the hypothesis that low body condition score (BCS) is associated with an increased risk of lameness in dairy cows. Mixed effect multinomial logistic regression models were used to investigate the association between prior BCS and repeat lameness events during the longitudinal period of the study. Discrete time survival models were used to explore the relationship between prior BCS and first lifetime lameness events. In total, 79,565 cow weeks at risk were obtained for 724 cows. The number of lameness events was 17,114, of which 8,799 were categorized as mildly lame and 8,315 as severely lame. The median BCS was 2.25 (range, 0.75 to 4.25) and the mean body weight (BW) and age at first calving were 619.5 kg (range, 355.6 to 956.4 kg) and 25.8 mo (range, 20.5 to 37.8 mo), respectively. Subsets of the data were used in the discrete time survival models: 333 mild and 211 severe first lifetime lameness events in heifers (first lactation cows), and 81 mild and 49 severe first lifetime lameness events in cows second lactation or greater. Low BCS 3 wk before a repeated lameness event was associated with a significantly increased risk of lameness. Cows with BCS<2 were at greatest risk of mild or severe lameness, and an increased BCS above 2 was associated with a reduced risk of mild or severe lameness. Low BCS 16 or 8 wk before a first mild or severe lifetime lameness event, respectively, also had a positive association with risk of lameness in cows second lactation or greater. This provides evidence to support targeting management toward maintaining BCS to minimize the

  9. A cross sectional observational study to estimate herd level risk factors for Leptospira spp. serovars in small holder dairy cattle farms in southern Chile

    PubMed Central

    2014-01-01

    Background The south of Chile constitutes the main cattle milk producing area of the country. Regarding leptospirosis control in Chile, there is neither an official program nor an epidemiological characterization of smallholder dairy farms. This study was carried out to determine Leptospira seroprevalence and to evaluate risk factors associated with seropositivity at herd level in smallholder bovine dairy herds in southern Chile. A cross-sectional study was conducted, and a convenient sample of 1,537 apparently healthy dairy cows was included in the study. Individual blood samples were taken and examined for six selected reference Leptospira serovars by the Microscopic Agglutination Test (MAT). Results Of the included herds 75% (52/69) showed serological titers against one or more Leptospira serovar. Leptospira borgpetersenii serovar Hardjo was the serovar most frequently (81%) reported from animals with positive results. The variables considered risk factors for Leptospira seropositivity were calve natural breeding system, using a specific calving area and vaccination against Leptospira. Adult cows in contact with calves weaned, proved to be a protective factor against infection. Conclusions Herds neglecting the management practices mentioned in this study could represent an important source of Leptospira infection for other herds in the same geographic area, as well as for other animal species. PMID:24906684

  10. Chronic copper toxicity in a dairy herd

    PubMed Central

    Perrin, David J.; Schiefer, H. Bruno; Blakley, Barry R.

    1990-01-01

    The addition of excessive copper to a commercially prepared dairy ration caused chronic copper toxicity in a dairy herd. A formulation error by a feed company resulted in copper levels of 800 to 1,000 mg/kg in the “as fed concentrate,” amounting to about 400-500 mg copper/kg of the whole ration. Five animals died with typical signs of acute copper toxicity, including intravascular hemolysis and methemoglobinemia. A further 39 cows died on the farm from a combination of debilitation and secondary infectious causes, and 215 were sent to slaughter because of debilitation and poor milk production. The mortality of calves born to dams that had been fed the toxic concentrate was approximately 50%. We postulate that dairy cows, particularly pregnant cows, may be more susceptible to copper toxicity than other cattle, and suggest reexamination of the presently allowable maximum levels of copper supplementation of diets for dairy cattle. PMID:17423660

  11. Herd level approach to high bulk milk somatic cell count problems in dairy cattle.

    PubMed

    Barkema, Herman W; De Vliegher, Sarne; Piepers, Sofie; Zadoks, Ruth N

    2013-06-01

    Since the introduction of the standard mastitis prevention program in the late 1960s, enormous progress has been made in decreasing the average bulk milk somatic cell count (BMSCC). In many countries, reduction of BMSCC has been encouraged through premium payments or penalty systems. However, the success of the program depends heavily on consistent implementation of management practices. The approach to problem solving in a herd with high BMSCC must include the following elements: (1) problem definition using primary udder health parameters; (2) detection of cows causing the problem; (3) definition of short- and long-term goals; (4) formulation and implementation of a herd management plan; and (5) evaluation of the results. Findings and plans are recorded for use at follow-up visits. Every high BMSCC problem can be solved if farmers are sufficiently motivated, if farm advisors are sufficiently knowledgeable, and if farmer and advisors work together according to a jointly determined plan. PMID:23706026

  12. [Red discolouration of the urine in a dairy cattle herd as a stock problem].

    PubMed

    Müller, K; Kamphues, J; Wolf, P; Huchzermeyer, B; Kaske, M

    2012-01-01

    After feeding a new batch of rapeseed meal (2.5 kg/cow/day) in the total mixed ration (TMR) of dairy cows on a dairy farm in Bavaria, numerous puddles of reddish fluid were found on the floor of the cubicle housing system. These were caused by a red discolouration of the urine. Directly after urination, the urine was macroscopically yellow and bright; the discolouration developed throughout the consecutive hours. Feed intake was markedly decreased and milk yield was lowered by 10%. No disturbances of the general health and blood key parameters were evident. After feeding two other cows with rapeseed meal of this batch (three times daily 1 kg each), the phenomenon occurred in one animal on the third and fourth days. Further analyses revealed evidence that the discolouration was due to substances which were excreted via the kidney and led to reddish urine after delayed reaction with the oxygen in the air.

  13. Quantification of antimicrobial consumption in adult cattle on dairy herds in Flanders, Belgium, and associations with udder health, milk quality, and production performance.

    PubMed

    Stevens, M; Piepers, S; Supré, K; Dewulf, J; De Vliegher, S

    2016-03-01

    The main objective of this study was to quantify the (compound-specific) antimicrobial consumption (AMC) in adult cattle in a convenience sample of Flemish dairy herds. Antimicrobial consumption data were obtained between 2012 and 2013 by "garbage can audits" and expressed as antimicrobial treatment incidence (ATI), with the unit of the ATI being the number of defined daily doses animal (DDDA) used per 1,000 cow-days. Herds were stratified by DDDA into low-, medium-, and high-consuming herds to study the AMC per route of administration, and associations with parameters reflecting udder health, milk quality, and production performances were examined. The average ATI in adult dairy cattle for all compounds was 20.78 DDDA (per 1,000 cow-days). Large variation existed between herds (ranging from 8.68 to 41.62 DDDA). Fourth-generation cephalosporins were used most (4.99 DDDA), followed by penicillins (3.70 DDDA) and third-generation cephalosporins (2.95 DDDA). The average ATI of the critically important antimicrobials for human health (i.e., third- and fourth-generation cephalosporins and fluoroquinolones according to the World Organisation for Animal Health classification) was somewhat lower than the average ATI of the other antimicrobials (8.59 and 12.18 DDDA, respectively). The average ATI for intramammary treatment of (sub)clinical mastitis, for dry-cow therapy, and for systemically administered antimicrobials was 6.30, 6.89, and 7.44 DDDA, respectively. In low-consuming herds, most antimicrobials were being used for dry-cow therapy, whereas in high-consuming herds, most antimicrobials were being used as injectable or intramammary mastitis therapy. The incidence rate of treated mastitis was positively associated with ATI. Herds that applied blanket dry-cow therapy tended to have a higher ATI than herds in which cows were selectively dried off with long-acting antimicrobials. The ATI decreased with an increasing prevalence of primiparous cows. PMID:26778315

  14. Evaluation of a coagulase-negative variant of Staphylococcus aureus as a cause of intramammary infections in a herd of dairy cattle.

    PubMed

    Fox, L K; Besser, T E; Jackson, S M

    1996-09-15

    A coagulase-negative variant of Staphylococcus aureus was identified in a herd of 250 lactating dairy cows. During testing of the entire herd, this strain of S aureus was isolated from aseptically collected milk samples of 25 cows. Cows with intramammary infections attributable to coagulase-negative S aureus had an increased somatic cell count in their milk, which was indicative of mastitis infection. Speciation of the Staphylococcus organisms was made, using a series of biochemical tests. A strain of a coagulase-positive S aureus also caused intramammary infections in the herd and shared identical biochemical characteristics with the coagulase-negative strain. Moreover, both strains could not be typed by the use of the International Set of Bovine Phages. Analysis of these findings indicated that a coagulase-negative variant of S aureus can cause intramammary infections in cattle, coagulase-negative variants of S aureus that cause mastitis can be more prevalent in herds than coagulase-positive variants, and clinicians should avoid misclassifying coagulase-negative S aureus as organisms that are clinically unimportant.

  15. The effect of reproductive performance on the dairy cattle herd value assessed by integrating a daily dynamic programming model with a daily Markov chain model.

    PubMed

    Kalantari, A S; Cabrera, V E

    2012-10-01

    The objective of this study was to determine the effect of reproductive performance on dairy cattle herd value. Herd value was defined as the herd's average retention payoff (RPO). Individual cow RPO is the expected profit from keeping the cow compared with immediate replacement. First, a daily dynamic programming model was developed to calculate the RPO of all cow states in a herd. Second, a daily Markov chain model was applied to estimate the herd demographics. Finally, the herd value was calculated by aggregating the RPO of all cows in the herd. Cow states were described by 5 milk yield classes (76, 88, 100, 112, and 124% with respect to the average), 9 lactations, 750 d in milk, and 282 d in pregnancy. Five different reproductive programs were studied (RP1 to RP5). Reproductive program 1 used 100% timed artificial insemination (TAI; 42% conception rate for first TAI and 30% for second and later services) and the other programs combined TAI with estrus detection. The proportion of cows receiving artificial insemination after estrus detection ranged from 30 to 80%, and conception rate ranged from 25 to 35%. These 5 reproductive programs were categorized according to their 21-d pregnancy rate (21-d PR), which is an indication of the rate that eligible cows become pregnant every 21 d. The 21-d PR was 17% for RP1, 14% for RP2, 16% for RP3, 18% for RP4, and 20% for RP5. Results showed a positive relationship between 21-d PR and herd value. The most extreme herd value difference between 2 reproductive programs was $77/cow per yr for average milk yield (RP5 - RP2), $13/cow per yr for lowest milk yield (RP5 - RP1), and $160/cow per yr for highest milk yield (RP5 - RP2). Reproductive programs were ranked based on their calculated herd value. With the exception of the best reproductive program (RP5), all other programs showed some level of ranking change according to milk yield. The most dramatic ranking change was observed in RP1, which moved from being the worst ranked

  16. The association between calfhood bovine respiratory disease complex and subsequent departure from the herd, milk production, and reproduction in dairy cattle.

    PubMed

    Schaffer, Aaron P; Larson, Robert L; Cernicchiaro, Natalia; Hanzlicek, Gregg A; Bartle, Steven J; Thomson, Daniel U

    2016-05-15

    OBJECTIVE To describe the frequency of calfhood producer-identified bovine respiratory disease complex (BRDC) in Holstein replacement heifers on 1 large farm and determine associations between development of BRDC at ≤ 120 days of age (BRDC120) with milk production estimate, calving interval, and risk of departure from the herd (DFH). DESIGN Retrospective, observational study. ANIMALS 14,024 Holstein heifer calves born on 1 farm. PROCEDURES Data were obtained from herd management records. Cox proportional hazard and generalized linear mixed-effects models were used to assess associations for variables of interest (BRDC120 status, demographic data, and management factors) with DFH, milk production estimate, and calving interval. RESULTS Except for the year 2007, animals identified as having BRDC120 were 1.62 to 4.98 times as likely to leave the herd before first calving, compared with those that did not have this designation. Calves identified as having BRDC prior to weaning were 2.62 times as likely to have DFH before first calving as those classified as developing BRDC after weaning. Cows identified as having BRDC120 were 1.28 times as likely to have DFH between the first and second calving as were other cows. The BRDC120 designation was associated with a 233-kg (513-lb) lower 305-day mature equivalent value for first lactation milk production, but was not associated with longer or shorter calving intervals at maturity. CONCLUSIONS AND CLINICAL RELEVANCE Dairy cattle identified as having BRDC120 had increased risk of DFH before the first or second calving and lower first-lactation milk production estimates, compared with results for cattle without this finding. Further investigation of these associations is warranted. PMID:27135672

  17. First description of Bartonella bovis in cattle herds in Israel.

    PubMed

    Rudoler, Nir; Rasis, Michal; Sharir, Benny; Novikov, Anna; Shapira, Gregory; Giladi, Michael

    2014-09-17

    Bartonella bovis has been described in beef and dairy cattle worldwide, however the reported prevalence rates are inconsistent, with large variability across studies (0-89%). This study describes the first isolation and characterization of B. bovis among cattle herds in the Middle East. Blood samples from two beef cattle herds (each sampled thrice) and one dairy herd (sampled twice) in Israel were collected during a 16-months period. Overall, 71 of 95 blood samples (75%) grew Bartonella sp., with prevalence of 78% and 59% in beef and dairy cattle, respectively. High level bacteremia (≥100,000 colony forming units/mL) was detected in 25 specimens (26%). Such high-level bacteremia has never been reported in cattle. Two dairy cows and one beef cow remained bacteremic when tested 60 or 120 days apart, respectively, suggesting that cattle may have persistent bacteremia. One third of animals were infested with ticks. Sequence analysis of a gltA fragment of 32 bacterial isolates from 32 animals revealed 100% homology to B. bovis. Species identification was confirmed by sequence analysis of the rpoB gene. Phylogenetic analysis based on the concatenated sequences of gltA and rpoB demonstrated that the isolates described herein form a monophyletic group with B. bovis strains originating from cattle worldwide. Taken together, the high prevalence of bacteremia, including high-level bacteremia, in beef and dairy cattle, the potential to develop prolonged bacteremia, the exposure of cattle to arthropod vectors, and proximity of infected animals to humans, make B. bovis a potential zoonotic agent.

  18. Evaluating results of the Welfare Quality multi-criteria evaluation model for classification of dairy cattle welfare at the herd level.

    PubMed

    de Vries, M; Bokkers, E A M; van Schaik, G; Botreau, R; Engel, B; Dijkstra, T; de Boer, I J M

    2013-10-01

    The Welfare Quality multi-criteria evaluation (WQ-ME) model aggregates scores of single welfare measures into an overall assessment for the level of animal welfare in dairy herds. It assigns herds to 4 welfare classes: unacceptable, acceptable, enhanced, or excellent. The aim of this study was to demonstrate the relative importance of single welfare measures for WQ-ME classification of a selected sample of Dutch dairy herds. Seven trained observers quantified 63 welfare measures of the Welfare Quality protocol in 183 loose housed- and 13 tethered Dutch dairy herds (herd size: 10 to 211 cows). First, values of welfare measures were compared among the 4 welfare classes, using Kruskal-Wallis and Chi-squared tests. Second, observed values of single welfare measures were replaced with a fictitious value, which was the median value of herds classified in the next highest class, to see if improvement of a single measure would enable a herd to reach a higher class. Sixteen herds were classified as unacceptable, 85 as acceptable, 78 as enhanced, and none as excellent. Classification could not be calculated for 17 herds because data were missing (15 herds) or data were deemed invalid because the stockperson disturbed behavioral observations (2 herds). Herds classified as unacceptable showed significantly more very lean cows, more severely lame cows, and more often an insufficient number of drinkers than herds classified as acceptable. Herds classified as acceptable showed significantly more cows with high somatic cell count, with lesions, that could not be approached closer than 1m, colliding with components of the stall while lying down, and lying outside the lying area, and showed fewer cows with diarrhea, more often had an insufficient number of drinkers, and scored lower for the descriptors "relaxed" and "happy" than herds classified as enhanced. Increasing the number of drinkers and reducing the percentage of cows colliding with components of the stall while lying down

  19. The effect of lameness on the resting behavior and metabolic status of dairy cattle during the transition period in a freestall-housed dairy herd.

    PubMed

    Calderon, D F; Cook, N B

    2011-06-01

    The objective of this observational study was to examine the effect of lameness on the resting behavior of dairy cattle through the transition period in a mattress-bedded commercial freestall facility, and explore the relationships between lameness, behavior, and metabolic indicators of disease. A convenience sample was used, comprised of 40 multiparous and 17 primiparous Holstein cows that were recruited as they entered the close-up pen and tracked through the maternity, hospital, and fresh pens. At recruitment, 87.5% of multiparous cows and 23.5% of primiparous cows showed evidence of abnormal gait. Lying time decreased from 16 d before calving from a least squares means ± standard error of 13.5 ± 0.6 h/d to a nadir of 10.6 ± 0.38 h/d on the day of calving. After a period of increased rest after calving, lying time stabilized by d 6 to between 9.8 and 10.8h/d. This change was accompanied by an increase in the number of lying bouts per day from least squares means (95% confidence limits) of 11.2 (10.0 to 12.4) bouts per day to a peak of 17.7 (16.5 to 18.8) bouts per day on the day before calving, and a decrease in the duration of each lying bout. Resting behavior was influenced by calving month, temperature humidity index, body condition, parity, and lameness. Moderate and severely lame cows had significantly longer lying times throughout the transition period before and after calving, but most notable was a dramatic increase in the number of lying bouts observed 3 d before and after calving. In the straw-bedded, loose-housed maternity pen, moderate and severely lame cows had 20.3 (19.1 to 21.5) bouts per day, compared with 15.6 (14.3 to 16.8) bouts per day for nonlame cows. We hypothesized that this alteration in behavior may be associated with hypersensitivity to pain due to lameness. A total of 26.3% of cows tested above a threshold of 1,400 μM β-hydroxybutyrate. Moderate and severely lame cows had a least squares means (95% confidence limits)

  20. Haematological profile of crossbred dairy cattle to monitor herd health status at medium elevation in Central Himalayas.

    PubMed

    Kumar, B; Pachauri, S P

    2000-10-01

    Haematological profile-haemoglobin concentration (Hb), total erythrocytes count (TEC), packed cell volume (PCV), erythrocyte indices-mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH) and mean corpuscular haemoglobin concentration (MCHC) were studied in crossbred dairy cattle (Holstein Friesian x Sahiwal) under various physiological states: non-pregnant heifers (NPH), pregnant heifers (PH), empty dry cows (EDC), pregnant lactating cows (PLC), medium yield early lactating cows (MYELC) and high yield early lactating cows (HYELC) during summer and winter seasons at 1700 metres altitude from mean sea level in the Central Himalayas. On comparison of annual means, the highest values of Hb and PCV were recorded in PH and of TEC in NPH, whereas the lowest values of these parameters were found in EDC. The Hb and TEC tended to decrease with increasing milk yield. Comparison of annual means of erythrocyte indices revealed the highest MCV and MCH in EDC, which simultaneously showed the lowest MCHC. Significant seasonal variations in haematological profile were recorded. The overall group mean (OGM) of Hb, MCV, MCH and MCHC was found to be significantly higher (P < 0.01) during summer whereas the TEC and PCV showed higher OGM (P < 0.01) during the winter season.

  1. Benchmarking dairy herd health status using routinely recorded herd summary data.

    PubMed

    Parker Gaddis, K L; Cole, J B; Clay, J S; Maltecca, C

    2016-02-01

    Genetic improvement of dairy cattle health through the use of producer-recorded data has been determined to be feasible. Low estimated heritabilities indicate that genetic progress will be slow. Variation observed in lowly heritable traits can largely be attributed to nongenetic factors, such as the environment. More rapid improvement of dairy cattle health may be attainable if herd health programs incorporate environmental and managerial aspects. More than 1,100 herd characteristics are regularly recorded on farm test-days. We combined these data with producer-recorded health event data, and parametric and nonparametric models were used to benchmark herd and cow health status. Health events were grouped into 3 categories for analyses: mastitis, reproductive, and metabolic. Both herd incidence and individual incidence were used as dependent variables. Models implemented included stepwise logistic regression, support vector machines, and random forests. At both the herd and individual levels, random forest models attained the highest accuracy for predicting health status in all health event categories when evaluated with 10-fold cross-validation. Accuracy (SD) ranged from 0.61 (0.04) to 0.63 (0.04) when using random forest models at the herd level. Accuracy of prediction (SD) at the individual cow level ranged from 0.87 (0.06) to 0.93 (0.001) with random forest models. Highly significant variables and key words from logistic regression and random forest models were also investigated. All models identified several of the same key factors for each health event category, including movement out of the herd, size of the herd, and weather-related variables. We concluded that benchmarking health status using routinely collected herd data is feasible. Nonparametric models were better suited to handle this complex data with numerous variables. These data mining techniques were able to perform prediction of health status and could add evidence to personal experience in herd

  2. Benchmarking dairy herd health status using routinely recorded herd summary data.

    PubMed

    Parker Gaddis, K L; Cole, J B; Clay, J S; Maltecca, C

    2016-02-01

    Genetic improvement of dairy cattle health through the use of producer-recorded data has been determined to be feasible. Low estimated heritabilities indicate that genetic progress will be slow. Variation observed in lowly heritable traits can largely be attributed to nongenetic factors, such as the environment. More rapid improvement of dairy cattle health may be attainable if herd health programs incorporate environmental and managerial aspects. More than 1,100 herd characteristics are regularly recorded on farm test-days. We combined these data with producer-recorded health event data, and parametric and nonparametric models were used to benchmark herd and cow health status. Health events were grouped into 3 categories for analyses: mastitis, reproductive, and metabolic. Both herd incidence and individual incidence were used as dependent variables. Models implemented included stepwise logistic regression, support vector machines, and random forests. At both the herd and individual levels, random forest models attained the highest accuracy for predicting health status in all health event categories when evaluated with 10-fold cross-validation. Accuracy (SD) ranged from 0.61 (0.04) to 0.63 (0.04) when using random forest models at the herd level. Accuracy of prediction (SD) at the individual cow level ranged from 0.87 (0.06) to 0.93 (0.001) with random forest models. Highly significant variables and key words from logistic regression and random forest models were also investigated. All models identified several of the same key factors for each health event category, including movement out of the herd, size of the herd, and weather-related variables. We concluded that benchmarking health status using routinely collected herd data is feasible. Nonparametric models were better suited to handle this complex data with numerous variables. These data mining techniques were able to perform prediction of health status and could add evidence to personal experience in herd

  3. Associations between herd size, rate of expansion and production, breeding policy and reproduction in spring-calving dairy herds.

    PubMed

    Jago, J G; Berry, D P

    2011-08-01

    Dairy herd size is expected to increase in many European countries, given the recent policy changes within the European Union. Managing more cows may have implications for herd performance in the post-quota era. The objective of this study was to characterise spring-calving herds according to size and rate of expansion, and to determine trends in breeding policy, reproduction and production performance, which will inform industry of the likely implications of herd expansion. Performance data from milk recording herds comprising 775,795 lactations from 2,555 herds for the years 2004 to 2008 inclusive were available from the Irish Cattle Breeding Federation. Herds were classified into Small (average of 37 cows), Medium (average of 54 cows) and Large (average of 87 cows) and separately into herds that were not expanding (Nil expansion), herds expanding on average by three cows per year (Slow expansion) and herds expanding on average by eight cows per year (Rapid expansion). There was no association between rate of expansion and 305-day fat and protein yield. However, 305-day milk yield decreased and milk protein and fat percentage increased with increasing rate of expansion. There were no associations between herd size and milk production except for protein and fat percentage, which increased with increasing herd size. Average parity number of the cows decreased as rate of expansion increased and tended to decrease as herd size increased. In rapidly expanding herds, cow numbers were increased by purchasing more cattle. The proportion of dairy sires relative to beef sires used in the breeding programme of expanding herds increased and there was more dairy crossbreeding, albeit at a low rate. Similarly, large herds were using more dairy sires and fewer beef sires. Expanding herds and large herds had superior reproductive performance relative to non-expanding and small herds. Animals in expanding herds calved for the first time at a younger age, had a shorter calving

  4. Management practices on organic and conventional dairy herds in Minnesota.

    PubMed

    Sorge, U S; Moon, R; Wolff, L J; Michels, L; Schroth, S; Kelton, D F; Heins, B

    2016-04-01

    The objective of this study was to describe and compare husbandry practices on organic and conventional dairy farms of similar sizes in Minnesota. Organic (ORG, n=35), same-sized conventional (SC, n=15, <200 cows) and medium-sized conventional (MC, n=13, ≥200 cows) dairy herds were visited in 2012, and farmers were interviewed once about their farm, herd demographics, and herd management practices concerning nutrition, housing, and reproductive programs. Organic farms had been established as long as conventional farms, and ORG producers had most commonly selected ORG farming because of a negative perception of pesticides for human health. The distribution of cattle breeds and ages differed across farm types. Organic farms had more crossbred cows and a greater number of older cows than conventional farms, who had mainly Holstein cattle. Organic farms did not dock tails, were more likely to use breeding bulls, and were less likely to conduct pregnancy diagnoses in cattle. All conventional farmers fed corn, corn silage, and hay, but no forage or feed supplement was fed by all ORG farms with the exception of pasture. Kelp was supplemented on most ORG farms but on none of the conventional farms. In summary, although there were differences across farm types regarding the use of pasture, feeds, and feed additives, breed and age distribution, reproductive management, and the use of tail docking, observations in other management areas showed large overlap across herd types. PMID:26830734

  5. Dietary abomasal impaction in a herd of dairy replacement heifers.

    PubMed

    Mitchell, K J

    1991-04-15

    An episode of dietary abomasal impaction in a herd of dairy replacement heifers was found to be caused by excess almond shells in the ration. Clinical signs and necropsy findings led to the diagnosis. Removal of the almond shells and increasing the energy and digestibility of the ration corrected the problem. Factors contributing to the dietary impactions included advanced stages of pregnancy, high energy demands of growing heifers, and cold weather. Dietary abomasal impactions are not common in dairy cattle because of the high-quality ration a dairy cow generally receives. Replacement heifers in advanced stages of pregnancy have nutritional requirements similar to those of dairy cows, yet are often nutritionally neglected. The clinical findings in this report may help make veterinarians aware of the possibility of dietary abomasal impactions in dairy replacement heifers fed low-quality feeds.

  6. Incidences of and genetic parameters for mastitis, claw disorders, and common health traits recorded in dairy cattle contract herds.

    PubMed

    Gernand, E; Rehbein, P; von Borstel, U U; König, S

    2012-04-01

    Test-day records for protein yield, protein percent, fat percent and somatic cell score combined with diagnoses for health traits from 19,870 Holstein cows kept in 9 large-scale contract herds in the region of Thuringia, Germany, were used to infer genetic parameters. From an electronic database system for recording diagnoses, 15 health disorders with highest incidences were extracted and grouped into the following 5 disease categories: claw disorders, mastitis, female fertility, metabolism, and ectoparasites. In a bayesian approach, threshold methodology was applied for binary distributed health disorders and linear models were used for gaussian test-day observations. Variances and variance ratios for health disorders were from univariate and covariance components among health disorders and between health disorders, and test-day production traits were from bivariate repeatability models. Incidences of health disorders increased with increasing parity and were substantially higher at the beginning of lactation. Only incidences for ectoparasites slightly increased with increasing stage of lactation. Heritabilities ranged from 0.00 for ectoparasites to 0.22 for interdigital hyperplasia. Heritabilities of remaining health disorders were in a narrow range between 0.04 (corpus luteum persistent) and 0.09 (dermatitis digitalis). Clustering diseases into categories did not result in higher heritabilities. The variance ratio of the permanent environmental component was higher than the heritability for the same trait, pointing to the conclusion that non-genetic factors influence repeated occurrence of health problems during lactation. Repeatabilities were relatively high with values up to 0.49 for interdigital hyperplasia. Genetic correlations among selected health disorders were low and close to zero, disproving the assumption that a cow being susceptible for a specific disease is also susceptible for other types of health disorders. Antagonistic genetic relationships

  7. Herd-level risk factors for infection with bovine leukemia virus in Canadian dairy herds.

    PubMed

    Nekouei, Omid; VanLeeuwen, John; Sanchez, Javier; Kelton, David; Tiwari, Ashwani; Keefe, Greg

    2015-05-01

    Enzootic bovine leukosis (EBL) is an economically important infection of dairy cattle worldwide, which is caused by bovine leukemia virus (BLV). The prevalence of infection in Canadian dairy herds is high and continues to increase; however, there has not been a national program to control BLV. This cross-sectional study was conducted to identify potentially important risk factors for BLV infection on Canadian dairy herds, which is a prerequisite to developing an effective control program. During 1998-2003, based on a stratified two-stage random sampling process, 315 dairy farms from seven provinces of Canada were selected. Within each farm, 9-45 cows were bled and tested with a commercial serum ELISA kit for BLV antibodies. A comprehensive questionnaire, targeting potentially important herd-level management indicators, was successfully administered in 272 herds. A zero-inflated negative binomial (ZINB) regression model was fit to the resulting data to assess the potential associations between BLV seropositivity and a variety of herd-level factors. Seventy-eight percent of the herds were identified as BLV-positive (had one or more test positive animals). In the negative-binomial part of the final ZINB model, herds with clinical cases of leukosis during the 12 months prior to sampling, as well as herds which purchased animals with unknown BLV infection status in the last five years, had a significantly larger proportion of BLV positive animals. Based on a significant interaction between two of the risk factors, changing gloves between cows during pregnancy examination was not statistically associated with lower proportion of infected cows compared with not changing gloves, in the western Canadian provinces. In the logistic part of the model, herds from eastern Canadian provinces and those not purchasing cows in the last five years had increased odds of being free from BLV. The high prevalence of infection across Canada should be addressed through the development and

  8. Genomic prediction of dry matter intake in dairy cattle from an international data set consisting of research herds in Europe, North America, and Australasia.

    PubMed

    de Haas, Y; Pryce, J E; Calus, M P L; Wall, E; Berry, D P; Løvendahl, P; Krattenmacher, N; Miglior, F; Weigel, K; Spurlock, D; Macdonald, K A; Hulsegge, B; Veerkamp, R F

    2015-09-01

    With the aim of increasing the accuracy of genomic estimated breeding values for dry matter intake (DMI) in Holstein-Friesian dairy cattle, data from 10 research herds in Europe, North America, and Australasia were combined. The DMI records were available on 10,701 parity 1 to 5 records from 6,953 cows, as well as on 1,784 growing heifers. Predicted DMI at 70 d in milk was used as the phenotype for the lactating animals, and the average DMI measured during a 60- to 70-d test period at approximately 200 d of age was used as the phenotype for the growing heifers. After editing, there were 583,375 genetic markers obtained from either actual high-density single nucleotide polymorphism (SNP) genotypes or imputed from 54,001 marker SNP genotypes. Genetic correlations between the populations were estimated using genomic REML. The accuracy of genomic prediction was evaluated for the following scenarios: (1) within-country only, by fixing the correlations among populations to zero, (2) using near-unity correlations among populations and assuming the same trait in each population, and (3) a sharing data scenario using estimated genetic correlations among populations. For these 3 scenarios, the data set was divided into 10 sub-populations stratified by progeny group of sires; 9 of these sub-populations were used (in turn) for the genomic prediction and the tenth was used for calculation of the accuracy (correlation adjusted for heritability). A fourth scenario to quantify the benefit for countries that do not record DMI was investigated (i.e., having an entire country as the validation population and excluding this country in the development of the genomic predictions). The optimal scenario, which was sharing data, resulted in a mean prediction accuracy of 0.44, ranging from 0.37 (Denmark) to 0.54 (the Netherlands). Assuming near-unity among-country genetic correlations, the mean accuracy of prediction dropped to 0.40, and the mean within-country accuracy was 0.30. If no

  9. Suboptimal Herd Performance Amplifies the Spread of Infectious Disease in the Cattle Industry

    PubMed Central

    Gates, M. Carolyn; Woolhouse, Mark E. J.

    2014-01-01

    Farms that purchase replacement breeding cattle are at increased risk of introducing many economically important diseases. The objectives of this analysis were to determine whether the total number of replacement breeding cattle purchased by individual farms could be reduced by improving herd performance and to quantify the effects of such reductions on the industry-level transmission dynamics of infectious cattle diseases. Detailed information on the performance and contact patterns of British cattle herds was extracted from the national cattle movement database as a case example. Approximately 69% of beef herds and 59% of dairy herds with an average of at least 20 recorded calvings per year purchased at least one replacement breeding animal. Results from zero-inflated negative binomial regression models revealed that herds with high average ages at first calving, prolonged calving intervals, abnormally high or low culling rates, and high calf mortality rates were generally more likely to be open herds and to purchase greater numbers of replacement breeding cattle. If all herds achieved the same level of performance as the top 20% of herds, the total number of replacement beef and dairy cattle purchased could be reduced by an estimated 34% and 51%, respectively. Although these purchases accounted for only 13% of between-herd contacts in the industry trade network, they were found to have a disproportionately strong influence on disease transmission dynamics. These findings suggest that targeting extension services at herds with suboptimal performance may be an effective strategy for controlling endemic cattle diseases while simultaneously improving industry productivity. PMID:24671129

  10. Copper toxicity in a New Zealand dairy herd

    PubMed Central

    2014-01-01

    Chronic copper toxicity was diagnosed in a Jersey herd in the Waikato region of New Zealand following an investigation into the deaths of six cattle from a herd of 250 dry cows. Clinical signs and post-mortem examination results were consistent with a hepatopathy, and high concentrations of copper in liver and blood samples of clinically affected animals confirmed copper toxicity. Liver copper concentrations and serum gamma-glutamyl transferase activities were both raised in a group of healthy animals sampled at random from the affected herd, indicating an ongoing risk to the remaining cattle; these animals all had serum copper concentrations within normal limits. Serum samples and liver biopsies were also collected and assayed for copper from animals within two other dairy herds on the same farm; combined results from all three herds showed poor correlation between serum and liver copper concentrations. To reduce liver copper concentrations the affected herd was drenched with 0.5 g ammonium molybdate and 1 g sodium sulphate per cow for five days, and the herd was given no supplementary feed or mineral supplements. Liver biopsies were repeated 44 days after the initial biopsies (approximately 1 month after the end of the drenching program); these showed a significant 37.3% decrease in liver copper concentrations (P <0.02). Also there were no further deaths after the start of the drenching program. Since there was no control group it is impossible to quantify the effect of the drenching program in this case, and dietary changes were also made that would have depleted liver copper stores. Historical analysis of the diet was difficult due to poor record keeping, but multiple sources of copper contributed to a long term copper over supplementation of the herd; the biggest source of copper was a mineral supplement. The farmer perceived this herd to have problems with copper deficiency prior to the diagnosis of copper toxicity, so this case demonstrates the importance of

  11. Prevalence of contagious and environmental mastitis-causing bacteria in bulk tank milk and its relationships with milking practices of dairy cattle herds in São Miguel Island (Azores).

    PubMed

    Azevedo, Carla; Pacheco, Diana; Soares, Luísa; Romão, Ricardo; Moitoso, Mónica; Maldonado, Jaime; Guix, Roger; Simões, João

    2016-02-01

    This study aimed to assess the degree of contamination of bulk tank milk (BTM) by Staphylococcus spp. and coliform bacteria and to identify major milking practices that help perpetuate them in dairy cattle herds in São Miguel Island. In July 2014, BTM was sampled and a survey concerning local milking practices was conducted on 100 herds. Semi quantitative multiplex polymerase chain reaction detected coagulase-negative staphylococci, Escherichia coli, Staphylococcus aureus, and other coliform bacteria (Klebsiella oxytoca, Klebsiella pneumoniae, and Serratia marcescens) in 100, 75, 59, and 35 % of BTM, respectively. According to multivariable univariate models, on herds not using hot water for cleaning the milking machine and teat liners, there was at least 3.4 more odds (P < 0.01) to have S. aureus or coliform bacteria contamination in BTM. The likelihood of finding S. aureus in BTM was higher (P < 0.001) on herds without high hygiene during milking, when milking mastitic cows at the end, on abrupt cessation of milking at dry-off, and official milk control implementation. The glove use also favored (odds ratio (OR) 5.8; P < 0.01) the detection of coliform bacteria in BTM. Poor milking practices identified in this study should be avoided in order to decrease S. aureus and coliform bacteria contamination of BTM. Other factors associated with milk quality in São Miguel Island also should be further investigated.

  12. Prevalence of contagious and environmental mastitis-causing bacteria in bulk tank milk and its relationships with milking practices of dairy cattle herds in São Miguel Island (Azores).

    PubMed

    Azevedo, Carla; Pacheco, Diana; Soares, Luísa; Romão, Ricardo; Moitoso, Mónica; Maldonado, Jaime; Guix, Roger; Simões, João

    2016-02-01

    This study aimed to assess the degree of contamination of bulk tank milk (BTM) by Staphylococcus spp. and coliform bacteria and to identify major milking practices that help perpetuate them in dairy cattle herds in São Miguel Island. In July 2014, BTM was sampled and a survey concerning local milking practices was conducted on 100 herds. Semi quantitative multiplex polymerase chain reaction detected coagulase-negative staphylococci, Escherichia coli, Staphylococcus aureus, and other coliform bacteria (Klebsiella oxytoca, Klebsiella pneumoniae, and Serratia marcescens) in 100, 75, 59, and 35 % of BTM, respectively. According to multivariable univariate models, on herds not using hot water for cleaning the milking machine and teat liners, there was at least 3.4 more odds (P < 0.01) to have S. aureus or coliform bacteria contamination in BTM. The likelihood of finding S. aureus in BTM was higher (P < 0.001) on herds without high hygiene during milking, when milking mastitic cows at the end, on abrupt cessation of milking at dry-off, and official milk control implementation. The glove use also favored (odds ratio (OR) 5.8; P < 0.01) the detection of coliform bacteria in BTM. Poor milking practices identified in this study should be avoided in order to decrease S. aureus and coliform bacteria contamination of BTM. Other factors associated with milk quality in São Miguel Island also should be further investigated. PMID:26719295

  13. Association between cattle herd Mycobacterium avium subsp. paratuberculosis (MAP) infection and infection of a hare population.

    PubMed

    Salgado, Miguel; Monti, Gustavo; Sevilla, Iker; Manning, Elizabeth

    2014-10-01

    Paratuberculosis has long been considered a disease of domestic and wild ruminants only. The known host range of Mycobacterium avium subsp. paratuberculosis (MAP) was recently extended to include non-ruminant wildlife species believed to be exposed to spillover of MAP from infected domestic cattle herds. The aim of the present study was to assess the association between cattle herd MAP infection pressure level and the infection level of a hare population in two dairy farms of southern Chile. Fifty hares from a herd A and 42 hares from herd B were captured and sampled for MAP culture. The results showed a statistically significant association between the cattle herds' infection prevalence and the hare infection prevalence.

  14. Serratia marcescens mastitis in a dairy herd.

    PubMed

    Wilson, D J; Kirk, J H; Walker, R D; Bosworth, Q W

    1990-04-01

    Serratia marcescens caused clinical mastitis in 5 cows and nonclinical mastitis in 21 cows of a 190-cow herd. Repeated bacteriologic culture of specimens from the cows, postmilking teat dip, environment, and equipment was performed. Serratia marcescens was not isolated from the dip, environment, or equipment. Progress of the infection in cows was monitored for 10 months. Some cows remained infected with S marcescens for at least 10 months. Economic loss estimates were based on Dairy Herd Improvement Association linear score reports. The average nonclinical loss was about $22/cow. PMID:2184155

  15. Dental pathology in conventionally fed and pasture managed dairy cattle.

    PubMed

    Fadden, A N; Poulsen, K P; Vanegas, J; Mecham, J; Bildfell, R; Stieger-Vanegas, S M

    2016-01-01

    Healthy teeth are important in the first stages of digestion for dairy cattle, yet little is known about bovine dental disease. This study aimed to investigate dental pathology of dairy cattle in two parts. First dairy cattle cadaver heads (n=11) were examined at the time of culling. Second, the authors performed oral exams in cattle fed a total mixed ration (TMR) (n=200) and pasture-based (n=71) grazing cattle. Cadaver heads were imaged using radiography and computed tomography before gross dissection to study dental anatomy and pathology. The most prevalent dental abnormalities were excessive transverse ridging of the occlusal surface, the presence of diastemas and third molar dental overgrowths (M3DO) in cadaver heads. Average thickness of subocclusal dentine ranged from 3.5 mm to 5.8 mm in cheek teeth but was >10 mm in maxillary teeth with M3DO. Radiographic findings were compared with oral examinations in live cattle. Prevalence of M3DO upon oral examination was 19 per cent and 28 per cent in herds of cattle fed a TMR diet and 0 per cent in a herd of grazing cattle. Dental abnormalities are prevalent in dairy cattle but due to thin subocclusal dentine in the cheek teeth, established equine dental treatment methodology is not appropriate for bovine cheek teeth with the exception of those that have developed M3DO.

  16. Risk factors for herd breakdown with bovine tuberculosis in 148 cattle herds in the south west of England.

    PubMed

    Ramírez-Villaescusa, A M; Medley, G F; Mason, S; Green, L E

    2010-07-01

    Bovine tuberculosis (bTB) is caused by Mycobacterium bovis. The disease has a long latent period, heterogenous spread, can infect many species and can persist in the environment. In the UK, the rate of herd breakdowns (HBD) with bTB is increasing. A retrospective cohort study of 148 cattle herds was set up to investigate risk factors for HBD from October 2001 to November 2004. Herds were selected from farms located in the randomised badger culling trial (RBCT) and comprised holdings (24%) that were restocked with cattle after the foot and mouth disease (FMD) epidemic in 2001 and holdings (76%) that were continuously stocked throughout the FMD epidemic. Farmers were interviewed between June 2003 and February 2004. Questions on herd and farm management were asked for the period October 2001 to June 2003. Data on herd testing for bTB were sourced from the VetNet database and historic data from 1995 were used in the analysis. A discrete time survival analysis was used to examine factors associated with the risk of HBD. By the end of the study period, November 2004, 50% of study herds had experienced a HBD with bTB at least once. Farms that were restocked for less than 1 year after FMD had a reduced risk of HBD (P<0.01) compared with continuously stocked farms in the same year. This reduced risk did not persist after 1 year of restocking. Feeding vitamin and mineral lick supplements compared with not feeding these supplements also reduced the risk of HBD. Factors associated with an increased risk of HBD were storing manure and slurry indoors or in a closed container, spreading manure all year round, herds with dairy cattle compared with herds without dairy cattle, increasing herd size, purchase of cattle from markets, location of the farm in the proactive area of the RBCT compared with survey only and location of farms in Somerset and North Devon. The lower risk of HBD in the first year after restocking but not the second or third year suggests that removal of all

  17. High seroprevalence of Coxiella burnetii in dairy cattle in China.

    PubMed

    El-Mahallawy, Heba S; Kelly, Patrick; Zhang, Jilei; Yang, Yi; Zhang, Hui; Wei, Lanjing; Mao, Yongjiang; Yang, Zhangping; Zhang, Zhenwen; Fan, Weixing; Wang, Chengming

    2016-02-01

    Coxiella burnetii is the agent of Q fever, a zoonosis which occurs worldwide. As there is little reliable data on the organism in China, we investigated C. burnetii infections in dairy cattle herds around the country. Opportunistic whole blood samples were collected from 1140 dairy cattle in 19 herds, and antibodies to phase I and II C. burnetii antigens were detected using commercial ELISA kits. Seropositive cattle (381/1140, 33 %) were detected in 13 of the 15 surveyed provinces and in 16 of the 19 herds (84 %) studied. Our data indicates C. burnetii is widespread in China and that animal and human health workers should be aware of the possibility of Q fever infection in their patients.

  18. A screening sampling plan to detect Mycobacterium avium subspecies paratuberculosis-positive dairy herds.

    PubMed

    Serraino, A; Arrigoni, N; Ostanello, F; Ricchi, M; Marchetti, G; Bonilauri, P; Bonfante, E; Giacometti, F

    2014-01-01

    Mycobacterium avium ssp. paratuberculosis (MAP) is the etiological agent of paratuberculosis, a chronic contagious bacterial disease primarily affecting dairy cattle. Paratuberculosis represents a dual problem for the milk production chain: in addition to economic losses to affected herds, MAP may have zoonotic potential. Infected herds must be identified in order to implement programs designed to reduce the incidence of disease within and between herds and to prevent MAP from entering the food chain. The objective of this study was to evaluate the sensitivity and specificity of a screening sampling plan (SSP) to detect MAP-positive dairy herds by repetitive analysis of bulk tank milk (BTM) samples by ELISA and in-line milk filter (ILMF) samples by PCR. Samples from BTM and ILMF were collected twice from 569 dairy herds in southern Italy. Additionally, 12,016 individual milk samples were collected: 9,509 from 102 SSP-positive herds (SSP MAP-positive) and 2,507 from 21 randomly selected SSP-negative herds (SSP MAP-negative). There was a total of 126 SSP MAP-positive herds (i.e., 21.3% SSP MAP-positive herds; 95% confidence interval=18.0-24.9); the within-herd apparent prevalence (AP) ranged between 0.00 and 22.73% (mean 6.07%). A significant difference in within-herd AP was shown between SSP MAP-positive herds and SSP MAP-negative herds. A highly significant association was shown between the median AP herd status (>5%) and positivity to at least one ILMF or BTM sample. The SSP detected a minimum of 56.25% of low AP herds (AP ≤ 2.0%) up to a maximum of 100% of herds with a within-herd AP ≥ 8.0%. Overall, the SSP detected 85.57% of herds in which at least one individual milk sample was positive by ELISA. The proposed SSP was an inexpensive and useful tool to detect MAP-positive herds with a higher risk of infection diffusion and milk contamination. Although the SSP cannot be used for MAP-free certification of herds, it could be useful to prioritize appropriate

  19. Dynamic changes in antibody levels as an early warning of Salmonella Dublin in bovine dairy herds.

    PubMed

    Stockmarr, A; Bødker, R; Nielsen, L R

    2013-01-01

    Salmonella Dublin is a bacterium that causes disease and production losses in cattle herds. In Denmark, a surveillance and control program was initiated in 2002 to monitor and reduce the prevalence of Salmonella Dublin. In dairy herds, the surveillance includes herd classification based on bulk tank milk measurements of antibodies directed against Salmonella Dublin at 3-mo intervals. In this study, an "alarm herd" concept, based on the dynamic progression of these repeated measurements, was formulated such that it contains predictive power for Salmonella Dublin herd classification change from "likely free of infection" to "likely infected" in the following quarter of the year, thus warning the farmer 3 mo earlier than the present system. The alarm herd concept was defined through aberrations from a stable development over time of antibody levels. For suitable parameter choices, alarm herd status was a positive predictor for Salmonella Dublin status change in dairy herds, in that alarm herds had a higher risk of changing status in the following quarter compared with nonalarm herds. This was despite the fact that both alarm and nonalarm herds had antibody levels that did not indicate the herds being "likely infected" according to the existing classification system in the present quarter. The alarm herd concept can be used as a new early warning element in the existing surveillance program. Additionally, to improve accuracy of herd classification, the alarm herd concept could be incorporated into a model including other known risk factors for change in herd classification. Furthermore, the model could be extended to other diseases monitored in similar ways.

  20. Environmental contamination with Mycobacterium avium subsp. paratuberculosis in endemically infected dairy herds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Environmental contamination with Mycobacterium avium subsp. paratuberculosis (MAP) is thought to be the primary source of infection for dairy cattle. The exact link between fecal shedding of MAP by individual cows and environmental contamination levels at the herd level was explored with a cross-se...

  1. Improving the time efficiency of identifying dairy herds with poorer welfare in a population.

    PubMed

    de Vries, M; Bokkers, E A M; van Schaik, G; Engel, B; Dijkstra, T; de Boer, I J M

    2016-10-01

    Animal-based welfare assessment is time consuming and expensive. A promising strategy for improving the efficiency of identifying dairy herds with poorer welfare is to first estimate levels of welfare in herds based on data that are more easily obtained. Our aims were to evaluate the potential of herd housing and management data for estimating the level of welfare in dairy herds, and to estimate the associated reduction in the number of farm visits required for identification of herds with poorer welfare in a population. Seven trained observers collected data on 6 animal-based welfare indicators in a selected sample of 181 loose-housed Dutch dairy herds (herd size: 22 to 211 cows). Severely lame cows, cows with lesions or swellings, cows with a dirty hindquarter, and very lean cows were counted, and avoidance distance was assessed for a sample of cows. Occurrence of displacements (social behavior) was recorded in the whole barn during 120 min of observation. For the same herds, data regarding cattle housing and management were collected on farms, and data relating to demography, management, milk production and composition, and fertility were extracted from national databases. A herd was classified as having poorer welfare when it belonged to the 25% worst-scoring herds. We used variables of herd housing and management data as potential predictors for individual animal-based welfare indicators in logistic regressions at the herd level. Prediction was less accurate for the avoidance distance index [area under the curve (AUC)=0.69], and moderately accurate for prevalence of severely lame cows (AUC=0.83), prevalence of cows with lesions or swellings (AUC=0.81), prevalence of cows with a dirty hindquarter (AUC=0.74), prevalence of very lean cows (AUC=0.83), and frequency of displacements (AUC=0.72). We compared the number of farm visits required for identifying herds with poorer welfare in a population for a risk-based screening with predictions based on herd housing

  2. The relationship between antibody status to bovine corona virus and bovine respiratory syncytial virus and disease incidence, reproduction and herd characteristics in dairy herds

    PubMed Central

    2010-01-01

    Background Bovine respiratory syncytial virus (BRSV) and bovine corona virus (BCV) affects cattle worldwide. Our objective was to evaluate the effects of these infections on general health and reproduction parameters measurable on herd level and to explore the association between antibody status and some herd characteristics. Methods We collected a pooled milk sample from five primiparous cows from 79 Swedish dairy herds in September 2006. The samples were analysed for immunoglobulin G antibodies to BCV and BRSV with indirect enzyme-linked immunosorbent assays. Herd level data from 1 September 2005 to 30 August 2006 were accessed retrospectively. The location of the herds was mapped using a geographical information system. Results Ten herds were antibody negative to both viruses and were compared with 69 herds positive to BCV or BRSV or both. Positive herds had a higher (P = 0.001) bulk tank milk somatic cell count (BMSCC) compared with negative herds. The medians for all other analyzed health and reproductive parameters were consistently in favour of the herds negative to both viruses although the differences were not statistically significant. A higher proportion (P = 0.01) of herds used professional technicians for artificial insemination, rather than farm personnel, amongst the 33 herds negative to BCV compared with the 46 positive herds. Conclusions Our result shows that herds that were antibody positive to BCV and/or BRSV had a higher BMSCC compared with herds negative to BCV and BRSV. There was also tendency that negative herds had a better general herd health compared with positive. A higher proportion amongst the BCV negative herds used external technicians for AI instead of farm personnel, indicating that it is possible to avoid infection although having regular visits. Negative herds were located in close proximity to positive herds, indicating that local spread and airborne transmission between herds might not be of great importance and that herds can

  3. Low prevalence of Salmonella in Swedish dairy herds highlight differences between serotypes.

    PubMed

    Ågren, Estelle C C; Sternberg Lewerin, Susanna; Wahlström, Helene; Emanuelson, Ulf; Frössling, Jenny

    2016-03-01

    Legislated Salmonella control in Sweden has been in place since the 1960s. The purpose of this study was to investigate presence of Salmonella antibodies in dairy cattle herds and to provide a basis for decisions on how surveillance and control can be improved. Bulk milk samples from all Swedish dairy herds (n=4 683) were analysed with two different ELISAs; one detecting antibodies against Salmonella Dublin (Dublin ELISA), and one detecting antibodies against several of the serotypes causing bovine salmonellosis including S. Dublin (Bovine ELISA). Information about herds, i.e. geographical location, local animal density, number of test positive herds within 5km, animal trade and herd size, was based on register data. The results confirm a very low prevalence of Salmonella in Swedish dairy herds throughout the country with the exception of an island in the southeast. The test positive herds split into two groups; 41 herds (1%) positive in the Dublin ELISA, and 101 herds (2%) positive in the Bovine ELISA but negative in the Dublin ELISA. Geographical location of positive herds, and comparison of the results of the screening with serotypes previously isolated from some of the herds, indicated that the first group represents herds presently or previously infected with S. Dublin while the second group represents herds presently or previously infected with other serotypes. Differences in serological status between herds in different regions, of different size, with different animal purchase patterns et cetera, were tested using logistic regression. Presence of positive herds within 5km was significantly associated to testing positive. For herds testing positive in the Dublin ELISA, significant associations were also seen with herd size. Purchase of animals during the last year was not significantly associated with the outcome in the final models. We conclude that for future surveillance, the Bovine ELISA can be used to help in identifying infected herds, and the Dublin

  4. Herd factors associated with dairy cow mortality.

    PubMed

    McConnel, C; Lombard, J; Wagner, B; Kopral, C; Garry, F

    2015-08-01

    Summary studies of dairy cow removal indicate increasing levels of mortality over the past several decades. This poses a serious problem for the US dairy industry. The objective of this project was to evaluate associations between facilities, herd management practices, disease occurrence and death rates on US dairy operations through an analysis of the National Animal Health Monitoring System's Dairy 2007 survey. The survey included farms in 17 states that represented 79.5% of US dairy operations and 82.5% of the US dairy cow population. During the first phase of the study operations were randomly selected from a sampling list maintained by the National Agricultural Statistics Service. Only farms that participated in phase I and had 30 or more dairy cows were eligible to participate in phase II. In total, 459 farms had complete data for all selected variables and were included in this analysis. Univariable associations between dairy cow mortality and 162 a priori identified operation-level management practices or characteristics were evaluated. Sixty of the 162 management factors explored in the univariate analysis met initial screening criteria and were further evaluated in a multivariable model exploring more complex relationships. The final weighted, negative binomial regression model included six variables. Based on the incidence rate ratio, this model predicted 32.0% less mortality for operations that vaccinated heifers for at least one of the following: bovine viral diarrhea, infectious bovine rhinotracheitis, parainfluenza 3, bovine respiratory syncytial virus, Haemophilus somnus, leptospirosis, Salmonella, Escherichia coli or clostridia. The final multivariable model also predicted a 27.0% increase in mortality for operations from which a bulk tank milk sample tested ELISA positive for bovine leukosis virus. Additionally, an 18.0% higher mortality was predicted for operations that used necropsies to determine the cause of death for some proportion of dead

  5. Herd factors associated with dairy cow mortality.

    PubMed

    McConnel, C; Lombard, J; Wagner, B; Kopral, C; Garry, F

    2015-08-01

    Summary studies of dairy cow removal indicate increasing levels of mortality over the past several decades. This poses a serious problem for the US dairy industry. The objective of this project was to evaluate associations between facilities, herd management practices, disease occurrence and death rates on US dairy operations through an analysis of the National Animal Health Monitoring System's Dairy 2007 survey. The survey included farms in 17 states that represented 79.5% of US dairy operations and 82.5% of the US dairy cow population. During the first phase of the study operations were randomly selected from a sampling list maintained by the National Agricultural Statistics Service. Only farms that participated in phase I and had 30 or more dairy cows were eligible to participate in phase II. In total, 459 farms had complete data for all selected variables and were included in this analysis. Univariable associations between dairy cow mortality and 162 a priori identified operation-level management practices or characteristics were evaluated. Sixty of the 162 management factors explored in the univariate analysis met initial screening criteria and were further evaluated in a multivariable model exploring more complex relationships. The final weighted, negative binomial regression model included six variables. Based on the incidence rate ratio, this model predicted 32.0% less mortality for operations that vaccinated heifers for at least one of the following: bovine viral diarrhea, infectious bovine rhinotracheitis, parainfluenza 3, bovine respiratory syncytial virus, Haemophilus somnus, leptospirosis, Salmonella, Escherichia coli or clostridia. The final multivariable model also predicted a 27.0% increase in mortality for operations from which a bulk tank milk sample tested ELISA positive for bovine leukosis virus. Additionally, an 18.0% higher mortality was predicted for operations that used necropsies to determine the cause of death for some proportion of dead

  6. Fecal Shedding of Campylobacter and Arcobacter spp. in Dairy Cattle

    PubMed Central

    Wesley, I. V.; Wells, S. J.; Harmon, K. M.; Green, A.; Schroeder-Tucker, L.; Glover, M.; Siddique, I.

    2000-01-01

    Campylobacter jejuni, Campylobacter coli, and Arcobacter spp. were detected in feces of healthy dairy cows by highly specific multiplex-PCR assays. For C. jejuni, at this one-time sampling, cows from 80.6% of farm operations (n = 31) and 37.7% of individual dairy cattle fecal samples (n = 2,085) were positive. Farm management factors were correlated with prevalence in herds in which >25% of cows were positive for C. jejuni. Statistical significance was set at a P of 0.20. Using these criteria, application of manure with broadcast spreaders (P = 0.17), feeding of whole cottonseed or hulls (P = 0.17) or alfalfa (P = 0.15), and accessibility of feed to birds (P = 0.17) were identified as possible risk factors for C. jejuni infection. C. coli was detected in at least one animal in 19.4% of operations and 1.8% of individual cows (n = 2,085). At the herd level, use of broadcaster spreaders was not a risk factor for C. coli infection. For Arcobacter, cows from 71% of dairy operations (n = 31) and 14.3% of individual dairy cattle fecal samples (n = 1,682) were positive. At the herd level, for Arcobacter spp., feeding of alfalfa (P = 0.11) and use of individual waterers (P = 0.19) were protective. This is the first description of Arcobacter spp. in clinically healthy dairy cattle and the first attempt to correlate their presence with C. jejuni. PMID:10788372

  7. [Planned dairy herd health. I: General philosophy].

    PubMed

    Lourens, D C; Coubrough, R I

    1985-09-01

    A dairy herd health programme may be defined as a planned and co-ordinated approach which aims at achieving and maintaining optimal herd health, production and reproduction, the implementation of which is governed by sound economic principles. The object of this article is to present and discuss some facets of the background philosophy of the concept of herd health, and look at some of the pitfalls and shortcomings of their application in practice. In terms of production levels achieved in other developed countries, South Africa lags behind. While factors such as climate, environment, feed quality, and basic livestock potential may play a role in this difference, the single most important factor is undoubtedly the managemental approach. Modern livestock production requires a shift in emphasis of veterinary involvement towards a herd approach which promotes increased cost-effective production. The veterinarian forms part of a production team which, apart from himself, includes the farmer, farm labour and the animal scientist. The veterinarian has a key role in this endeavour. Through his basic training he is well equipped to serve as a co-ordinator of the massive flow of information being generated. To do this effectively he must be able to work with, advise and communicate with people at various levels of management as well as with the labour force. While optimal co-operation of each team member is cardinal to the success of such a programme, no progress will be made unless the farmer is convinced of the viability of the undertaking, and indeed has the managerial skills to implement any directive or recommendation.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:4078844

  8. Parasites and parasite management practices of organic and conventional dairy herds in Minnesota.

    PubMed

    Sorge, U S; Moon, R D; Stromberg, B E; Schroth, S L; Michels, L; Wolff, L J; Kelton, D F; Heins, B J

    2015-05-01

    The objective of this study was to describe the prevalence and practices used to manage internal helminth parasites and external arthropod parasites on organic and conventional dairy herds in Minnesota. All organic (ORG) dairy herds in Minnesota (n=114) and a convenience sample of conventional herds were invited to participate in the study. Thirty-five ORG herds and 28 conventional herds were visited once in summer and fall of 2012. Conventional dairy herds were split into small conventional (SC,<200 cows) and medium-sized conventional herds (MC, ≥200 cows) so that SC herds were comparable in size to the ORG herds. Dairy managers were surveyed to assess their farm management practices and perceptions about parasites, hygiene scores were recorded for adult stock, and fecal samples were collected from a nominal 20 breeding-age heifers to characterize abundance of internal parasites. Nonparametric tests were used to compare fecal egg counts per gram (FEC) among farms grouped by management systems and practices. Organic farms had more designated pasture and were more likely to use rotational grazing compared with conventional farms, but the stocking densities of animals on pasture were similar among farm types. The overall FEC were very low, and only a few individual ORG heifers had FEC >500 eggs/gram. Samples from heifers on ORG farms had significantly more strongyle-type eggs than those on SC and MC farms (ORG: 6.6±2.1; SC: 0.5±0.3; MC: 0.8±0.7), but egg counts of other types of gastrointestinal parasites did not differ significantly among the 3 herd groups. Fly control measures were applied mainly to milking cows and preweaned calves and were used on 88.6% of ORG herds, 60.0% of SC herds, and 91.7% of MC herds. Approximately half of the producers reported having seen skin conditions suggestive of lice or tail mange in their cattle during the previous winter (ORG: 48.6%, SC: 57.1%, MC: 53.9%). Although most conventional producers reported treating these skin

  9. Parasites and parasite management practices of organic and conventional dairy herds in Minnesota.

    PubMed

    Sorge, U S; Moon, R D; Stromberg, B E; Schroth, S L; Michels, L; Wolff, L J; Kelton, D F; Heins, B J

    2015-05-01

    The objective of this study was to describe the prevalence and practices used to manage internal helminth parasites and external arthropod parasites on organic and conventional dairy herds in Minnesota. All organic (ORG) dairy herds in Minnesota (n=114) and a convenience sample of conventional herds were invited to participate in the study. Thirty-five ORG herds and 28 conventional herds were visited once in summer and fall of 2012. Conventional dairy herds were split into small conventional (SC,<200 cows) and medium-sized conventional herds (MC, ≥200 cows) so that SC herds were comparable in size to the ORG herds. Dairy managers were surveyed to assess their farm management practices and perceptions about parasites, hygiene scores were recorded for adult stock, and fecal samples were collected from a nominal 20 breeding-age heifers to characterize abundance of internal parasites. Nonparametric tests were used to compare fecal egg counts per gram (FEC) among farms grouped by management systems and practices. Organic farms had more designated pasture and were more likely to use rotational grazing compared with conventional farms, but the stocking densities of animals on pasture were similar among farm types. The overall FEC were very low, and only a few individual ORG heifers had FEC >500 eggs/gram. Samples from heifers on ORG farms had significantly more strongyle-type eggs than those on SC and MC farms (ORG: 6.6±2.1; SC: 0.5±0.3; MC: 0.8±0.7), but egg counts of other types of gastrointestinal parasites did not differ significantly among the 3 herd groups. Fly control measures were applied mainly to milking cows and preweaned calves and were used on 88.6% of ORG herds, 60.0% of SC herds, and 91.7% of MC herds. Approximately half of the producers reported having seen skin conditions suggestive of lice or tail mange in their cattle during the previous winter (ORG: 48.6%, SC: 57.1%, MC: 53.9%). Although most conventional producers reported treating these skin

  10. Outbreak of Salmonella Thompson infection in a Swedish dairy herd.

    PubMed

    Sternberg, S; Johnsson, A; Aspan, A; Bergström, K; Kallay, T B; Szanto, E

    2008-11-15

    Salmonella Typhimurium was isolated from a faecal sample from a cow in a Swedish dairy herd after calving. When investigations were undertaken in the herd, Salmonella Thompson was isolated from heifers on a separate pasture, and when these heifers were brought into the herd S Thompson spread rapidly. Control strategies managed to rid the herd of the S Typhimurium infection and the prevalence of S Thompson was at first substantially reduced. There was a rapid increase in its prevalence when the animals were let out to pasture and this development eventually led to the depopulation of the entire herd. PMID:19011246

  11. Aspects of bovine herpesvirus 1 and bovine viral diarrhoea virus herd-level seroprevalence and vaccination in dairy and beef herds in Northern Ireland

    PubMed Central

    2014-01-01

    Background Infections with bovine herpesvirus 1 (BoHV-1) and bovine viral diarrhoea (BVD) virus cause diseases of cattle with a worldwide distribution. The primary objective of the present study was to describe aspects of herd-level BoHV-1 and BVDV seroprevalence (based on testing of pooled sera) and control on farms in Northern Ireland, including vaccine usage. An indirect antibody ELISA test (SVANOVA, Biotech AB, Uppsala, Sweden) was applied to serum pools which were constructed from serum samples taken for a cross-sectional study of a convenience sample of 500 Northern Irish dairy and beef cow herds in 2010, for which vaccination status was determined by telephone survey. The herd-level seroprevalence of BoHV-1 and BVDV in Northern Ireland was estimated in non-vaccinating herds and associations between possible risk factors (herd type and herd size (quartiles)) and herd-level prevalence were determined using chi-squared analysis. Results The herd-level seroprevalence (of BoHV-1 and BVDV) in non-vaccinating herds was 77.3% (95% CI: 73.6–80.9%) and 98.4% (95% CI: 97.3–99.5%) respectively in the cross-sectional study. A significant difference existed in BoHV-1 herd-level seroprevalence between dairy and beef herds (74.7% vs 86.5% respectively; p < 0.02) though not for BVDV seroprevalence (98.5% vs 98.3% respectively; p > 0.91). A significant association was found between herd size (quartiles) and herd-level classification for BoHV-1 herd-level seroprevalence based on cut-off percentage positivity (COPP) (p < 0.01) while no such association was found for BVDV (p = 0.22). 15.5% and 23.8% of farmers used BoHV-1 and BVDV vaccines, respectively. BoHV-1 vaccine was used in 30% of dairy herds and in 11% of beef herds, while BVDV vaccine was used in 46% and 16% of dairy and beef herds, respectively. Conclusions The results from this study indicate that the true herd-level seroprevalences to bovine herpesvirus 1 and bovine virus diarrhoea virus in non

  12. Soil ingestion by dairy cattle

    SciTech Connect

    Darwin, R.

    1990-02-15

    Ingested soil may be a source of minerals to grazing cattle; it may also be a source of radionuclides, heavy metals, and organic toxins. The importance of soil ingestion in the milk pathway depends on the amount of soil ingested, the ratio of the mineral concentration in soil to that in herbage, and the ability of the cattle to solubilize and absorb the soil-derived minerals. The amount of soil ingested by cattle on pasture, in turn, depends upon the stocking level, the quantity of forage available, and the soil ingesting propensity of individual cows. The objective of this note is to summarize some of the information about soil ingestion by dairy cattle and to suggest methods for incorporating soil ingestion into the Hanford Environmental Dose Reconstruction (HEDR) Phase I milk model. 5 refs., 4 tabs.

  13. Copper poisoning in a dairy herd fed a mineral supplement

    PubMed Central

    Bradley, Charles H.

    1993-01-01

    Copper poisoning in a dairy herd resulted in the death of 9 of 63 (14%) adult Holstein cows. Clinical signs were acute anorexia, weakness, mental dullness, poor pupillary light reflexes, and scant nasal discharge. These were followed by recumbency, chocolate-colored blood, jaundice, and death. Four animals exhibited signs of hyperesthesia and/or rumen stasis prior to death. At necropsy there was generalized icterus of body tissues, with the liver appearing orange and the kidneys dark blue. Histologically, there was accumulation of hemosiderin in Kupffer cells, and severe to moderate hepatocellular necrosis in all cases. Ammonium molybdate added to the ration, combined with the cessation of mineral supplementation, arrested the outbreak. These cases illustrate significant mortality, due to copper poisoning, in adult cattle fed a low-dose mineral dietary supplement for over two years. Dietary copper intake of the herd (on a dry matter basis) was 37.5 mg/kg for lactating cows and 22.6 mg/kg for dry cows. PMID:17424221

  14. Serological study of bovine herpes virus type 1 in dairy herds of Hamedan province, Iran.

    PubMed

    Bahari, Aliasghar; Gharekhani, Jamal; Zandieh, Masoumeh; Sadeghi-Nasab, Ali; Akbarein, Hesameddin; Karimi-Makhsous, Ahmad; Yavari, Morteza

    2013-01-01

    A cross-sectional study with a random cluster sampling design was carried out to estimate the seroprevalence of bovine herpesvirus type 1 (BHV-1) in non-vaccinated dairy herds in Hamedan province, west of Iran. Simple random sampling was used for selection of cattle in each herd. Informative data about each herd and selected animals were recorded by the farm manager in a provided questionnaire. Blood samples were collected from 492 animals in 41 industrial herds. A commercial indirect ELISA test was used to determine the seropositivity against BHV-1. The individual and herd seroprevalence for BHV-1 were 58.74% and 82.93%, respectively. The intra-herd prevalences were ranged from 16.70% to 100%. Geographical characteristics of Hamedan province may explain the high sero-prevalence rates found in this study compared to those of others obtained from different parts of the country. The proportion of seropositive cows were increased with age (p <0.05). Animals from large and moderate sized herds had higher odds of seropositivity than those of small size herds. These findings could be related to the presence of a considerable number of BHV-1 carriers in this region. The high herd and animal prevalence found in the present study suggested necessity of implementing an intensive control program for reducing BHV-1 infection rates.

  15. Mathematical Modeling of the Dynamics of Salmonella Cerro Infection in a US Dairy Herd

    NASA Astrophysics Data System (ADS)

    Chapagain, Prem; van Kessel, Jo Ann; Karns, Jeffrey; Wolfgang, David; Schukken, Ynte; Grohn, Yrjo

    2006-03-01

    Salmonellosis has been one of the major causes of human foodborne illness in the US. The high prevalence of infections makes transmission dynamics of Salmonella in a farm environment of interest both from animal and human health perspectives. Mathematical modeling approaches are increasingly being applied to understand the dynamics of various infectious diseases in dairy herds. Here, we describe the transmission dynamics of Salmonella infection in a dairy herd with a set of non-linear differential equations. Although the infection dynamics of different serotypes of Salmonella in cattle are likely to be different, we find that a relatively simple SIR-type model can describe the observed dynamics of the Salmonella enterica serotype Cerro infection in the herd.

  16. Control and eradication programme of enzootic bovine leucosis (EBL) from selected dairy herds in Turkey.

    PubMed

    Burgu, I; Alkan, F; Karaoglu, T; Bilge-Dagalp, S; Can-Sahna, K; Güngör, B; Demir, B

    2005-07-01

    Serum samples of 15,909 cattle from 31 dairy herds located in various regions of Turkey were tested for the presence of antibodies against bovine leucosis virus (BLV) using Agar Gel Immuno-diffusion technique (AGID). 48.3% (15/31) of the herds had seropositive animals and positivity rates were detected from 0.5-34.4% in these herds. In an EBL control/eradication programme all seropositive animals were culled in the infected herds. Thereafter, a total of 74,347 sera were tested for the presence of BLV specific antibodies. The serological results and detail of EBL control/eradication programme were shown in this paper. PMID:16124702

  17. Effect of grazing on the cow welfare of dairy herds evaluated by a multidimensional welfare index.

    PubMed

    Burow, E; Rousing, T; Thomsen, P T; Otten, N D; Sørensen, J T

    2013-05-01

    Structural development in the prime sector has led to increasing herd sizes and new barn systems, followed by less summer grazing for dairy cows in Denmark. Effects of grazing on single welfare measures in dairy cows - for example, the presence of integument alterations or mortality - have been studied under different conditions. However, the effect of grazing on welfare, conceptualised as the multidimensional physical and mental state of the animal, has not yet been studied in contemporary cubicle loose-housing systems. The aim of our study was to investigate, based on a Welfare Quality® inspired multidimensional dairy cow welfare assessment protocol, the within-herd effect of summer grazing compared with winter barn housing in Danish dairy herds with cubicle free-stall systems for the lactating cows. Our hypothesis was that cow welfare in dairy herds was better during summer grazing than during full-time winter housing. Furthermore, we expected improved welfare with an increase in daily summer grazing hours. In total, 41 herds have been visited once in the winter and once in the summer of 2010 to assess their welfare status with 17 different animal- and resource-based welfare measures. A panel of 20 experts on cattle welfare and husbandry evaluated the relative weight of the 17 welfare measures in a multidimensional assessment scheme. They estimated exact weights for a priori constituted severe compared with moderate scores of welfare impairment concerning each measure, as well as relevance of the measures in relation to each other. A welfare index (WI; possible range 0 to 5400) was calculated for each herd and season with a higher index indicating poorer welfare. The within-herd comparison of summer grazing v. winter housing considered all the 17 measures. The mean WI in summer was significantly lower (better) than in winter (mean 2926 v. 3330; paired t-test P = 0.0001) based on a better state of the integument, claw conformation and better access to water and

  18. Survival analysis of factors affecting incidence risk of Salmonella Dublin in Danish dairy herds during a 7-year surveillance period.

    PubMed

    Nielsen, Liza Rosenbaum; Dohoo, Ian

    2012-12-01

    A national surveillance programme for Salmonella Dublin, based on regular bulk-tank milk antibody screening and movements of cattle, was initiated in Denmark in 2002. From 2002 to end of 2009 the prevalence of test-positive dairy herds was reduced from 26% to 10%. However, new infections and spread of S. Dublin between herds continued to occur. The objective of this study was to investigate factors affecting incidence risk of S. Dublin infection in Danish dairy herds between 2003 and 2009. Herds were considered at risk when they had been test-negative for at least four consecutive year-quarters (YQs), either at the start of the study period or after recovery from infection. Survival analysis was performed on a dataset including 6931 dairy herds with 118,969 YQs at risk, in which 1523 failures (new infection events) occurred. Predictors obtained from register data were tested in a multivariable, proportional hazard model allowing for recurrence within herds. During October to December the hazard of failures was higher (hazard ratio HR=3.4, P=0.0005) than the rest of the year. Accounting for the delay in bulk-tank milk antibody responses to S. Dublin infection, this indicates that introduction of bacteria was most frequent between July and October. Purchase from test-positive cattle herds within the previous 6 months was associated with higher hazard of failures (HR=2.5, P<0.0001) compared to no purchase and purchase from test-negative herds. Increasing local prevalence, herd size and bulk-tank milk somatic cell counts were also associated with increasing hazard of failures. The effect of prior infection was time-dependent; the hazard of failures was reduced following a logarithmic decline with increasing time at risk. The hazard was markedly higher in herds with prior infections the first year after becoming at risk again, and then approached the hazard in herds without known prior infections 2-3 years after becoming test-negative. This showed that herds with prior

  19. Within-herd prevalence of Salmonella Dublin in endemically infected dairy herds.

    PubMed

    Nielsen, L R

    2013-10-01

    In this study within-herd prevalence of Salmonella Dublin was investigated in three age groups (calves, young stock, adult cows) during five herd visits at 3-month intervals of 14 endemically infected dairy herds. A total of 10162 paired faecal cultures and antibody measurements were used to calculate the age and temporal dynamics of seroprevalence and prevalence of positive faecal cultures. Faecal culture-positive prevalence was generally low. It was highest (5.4%) in calves during December to February. Seroprevalence varied from 0% to 70% between herds, but was generally more stable in young stock and adult cows than in calves. Hierarchical mixed-model results showed that seroprevalence was associated with the bacteriological status in calves and cows, but not in young stock. These results can be used to develop and validate theoretical infection dynamics models and to design effective control programmes for Salmonella Dublin in dairy herds.

  20. Genomic Selection Improves Heat Tolerance in Dairy Cattle

    PubMed Central

    Garner, J. B.; Douglas, M. L.; Williams, S. R. O; Wales, W. J.; Marett, L. C.; Nguyen, T. T. T.; Reich, C. M.; Hayes, B. J.

    2016-01-01

    Dairy products are a key source of valuable proteins and fats for many millions of people worldwide. Dairy cattle are highly susceptible to heat-stress induced decline in milk production, and as the frequency and duration of heat-stress events increases, the long term security of nutrition from dairy products is threatened. Identification of dairy cattle more tolerant of heat stress conditions would be an important progression towards breeding better adapted dairy herds to future climates. Breeding for heat tolerance could be accelerated with genomic selection, using genome wide DNA markers that predict tolerance to heat stress. Here we demonstrate the value of genomic predictions for heat tolerance in cohorts of Holstein cows predicted to be heat tolerant and heat susceptible using controlled-climate chambers simulating a moderate heatwave event. Not only was the heat challenge stimulated decline in milk production less in cows genomically predicted to be heat-tolerant, physiological indicators such as rectal and intra-vaginal temperatures had reduced increases over the 4 day heat challenge. This demonstrates that genomic selection for heat tolerance in dairy cattle is a step towards securing a valuable source of nutrition and improving animal welfare facing a future with predicted increases in heat stress events. PMID:27682591

  1. Age-structured dynamic, stochastic and mechanistic simulation model of Salmonella Dublin infection within dairy herds.

    PubMed

    Nielsen, Liza Rosenbaum; Kudahl, Anne Braad; Østergaard, Søren

    2012-06-01

    In the demand for a decision support tool to guide farmers wanting to control Salmonella Dublin (S. Dublin) in Danish dairy herds, we developed an age-structured stochastic, mechanistic and dynamic simulation model of S. Dublin in dairy herds, which incorporated six age groups (neonatal, preweaned calves, weaned calves, growing heifers, breeding heifers and cows) and five infection states (susceptible, acutely infected, carrier, super shedder and resistant). The model simulated population and infection dynamics over a period of 10 years in weekly time steps as: 1) population sizes of each of the six age-groups; 2) S. Dublin incidence and number of animals in each infection state; and 3) S. Dublin related morbidity and mortality in the acutely infected animals. The effects of introducing one infectious heifer on the risk of spread of S. Dublin within the herd and on the duration of infection were estimated through 1000 simulation iterations for 48 scenarios. The scenarios covered all combinations of three herd sizes (70, 200 and 400 cows), four hygiene levels indicating infectious contact parameters, and four herd susceptibility levels indicating different susceptibility parameters for the individual animals in each of the six age groups in the herd. The hygiene level was highly influential on the probability that the infection spread within the herd, duration of infection and epidemic size. The herd susceptibility level was also influential, but not likely to provide sufficient prevention and control of infection on its own. Herd size did not affect the probability of infection spread upon exposure, but the larger the herd the more important were management and housing practices that improve hygiene and reduce susceptibility to shorten durations of infection in the herd and to increase the probability of extinction. In general, disease and mortality patterns followed epidemic waves in the herds. However, an interesting pattern was seen for acute infections and

  2. 9 CFR 78.9 - Cattle from herds not known to be affected.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false Cattle from herds not known to be... BRUCELLOSIS Restrictions on Interstate Movement of Cattle Because of Brucellosis § 78.9 Cattle from herds not known to be affected. Male cattle which are not test eligible and are from herds not known to...

  3. 9 CFR 78.9 - Cattle from herds not known to be affected.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false Cattle from herds not known to be... BRUCELLOSIS Restrictions on Interstate Movement of Cattle Because of Brucellosis § 78.9 Cattle from herds not known to be affected. Male cattle which are not test eligible and are from herds not known to...

  4. 9 CFR 78.9 - Cattle from herds not known to be affected.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false Cattle from herds not known to be... BRUCELLOSIS Restrictions on Interstate Movement of Cattle Because of Brucellosis § 78.9 Cattle from herds not known to be affected. Male cattle which are not test eligible and are from herds not known to...

  5. 9 CFR 78.9 - Cattle from herds not known to be affected.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 1 2012-01-01 2012-01-01 false Cattle from herds not known to be... BRUCELLOSIS Restrictions on Interstate Movement of Cattle Because of Brucellosis § 78.9 Cattle from herds not known to be affected. Male cattle which are not test eligible and are from herds not known to...

  6. A cost/benefit study of paratuberculosis certification in French cattle herds.

    PubMed

    Dufour, Barbara; Pouillot, Régis; Durand, Benoît

    2004-01-01

    Paratuberculosis has received increasing attention in France because of the important losses this disease may provoke. The use of certification schemes has proven its effectiveness for the protection of healthy herds against diseases transmitted mainly by trade. The economic justification of such schemes in the particular case of paratuberculosis is studied, for French cattle herds, using a cost/benefit approach. The basic economical hypotheses and estimates have been proposed and carefully examined by a working group composed of paratuberculosis experts and field specialists. By adopting the point of view of a breeder that buys animals, we first estimated the benefits resulting from the non-introduction of the disease. They were then compared with the costs resulting from the fact that the vendor reports its own certification costs on the price of the animals he sells. Two average herds (the mean French beef herd and the mean French dairy herd), and two certification levels were studied. The results show that, currently, the use of the certification is not very economically profitable in French cattle herds. This conclusion, however should be reappraised if the certification costs decrease, for example with the commercialization of diagnostic tests on mixtures.

  7. Questionnaire identifying management practices surrounding calving on spring-calving dairy farms and their associations with herd size and herd expansion.

    PubMed

    Cummins, C; Berry, D P; Sayers, R; Lorenz, I; Kennedy, E

    2016-05-01

    Healthy calves are fundamental to any profitable dairy enterprise. Research to-date, has focused on year-round calving systems which experience many different challenges compared to spring-calving systems. The objective of the present study was to determine the on-farm dry cow, calving, and colostrum management practices of spring-calving dairy production systems, and quantify their associations with herd size and herd expansion status (i.e. expanding or not expanding). Information on these management practices was available from a survey of 262 Irish spring-calving dairy farmers, representative of the Irish national population. Herd expansion in the 2 years before, and the year that the survey was conducted was not associated with any of the management practices investigated. Fifty-three percent of respondents had an average calving season length of 10 to14 weeks with 35% of herds having a longer calving season. Previous research in cattle has documented that both colostrum source and feeding management are associated with the transmission of infectious disease from cow to calf. In the present study 60% of respondents fed calves colostrum from their own dam; however, 66% of those respondents allowed the calf to suckle the dam, 23% of survey respondents fed calves pooled colostrum. Larger herds were more likely (P<0.01) to use pooled colostrum supplies, while smaller herds were more likely (P<0.05) to allow the calf to suckle the dam. The majority (86%) of respondents had stored supplies of colostrum; average-sized herds had the greatest likelihood of storing colostrum (P<0.05), compared to other herd sizes; larger sized herds had a lesser likelihood (P<0.05) of storing colostrum in a freezer, compared to other herd sizes. Although freezing colostrum was the most common method used to store colostrum (54% of respondents), 17% of respondents stored colostrum at room temperature, 29% of which stored it at room temperature for greater than 4 days. The results from the

  8. Kappa-casein polymorphisms among cattle breeds and bison herds

    USGS Publications Warehouse

    Cronin, M.A.; Cockett, N.

    1993-01-01

    We identified the HindIII restriction site polymorphism Of kappa-casein in cattle reported by Pinder et al. (Animal Genetics 22, 11, 1991) and found an additonal polymorphism (RsaI) in cattle and bison. The Hin dIII and Rsa I restriction sites were mapped and three haplotypes (alleles) were identified. Preliminary screening of 39 cattle and 71 bison revealed one allele restricted to cattle, one restricted to bison, and one shared by the species. No fixed allelic differences were observed among cattle breeds or among bison herds or subspecies.

  9. Annual incidence, prevalence and transmission characteristics of Streptococcus agalactiae in Danish dairy herds.

    PubMed

    Mweu, Marshal M; Nielsen, Søren S; Halasa, Tariq; Toft, Nils

    2012-10-01

    Contagious mastitis pathogens continue to pose an economic threat to the dairy industry. An understanding of their frequency and transmission dynamics is central to evaluating the effectiveness of control programmes. The objectives of this study were twofold: (1) to estimate the annual herd-level incidence rates and apparent prevalences of Streptococcus agalactiae (S. agalactiae) in the population of Danish dairy cattle herds over a 10-year period from 2000 to 2009 inclusive and (2) to estimate the herd-level entry and exit rates (demographic parameters), the transmission parameter, β, and recovery rate for S. agalactiae infection. Data covering the specified period, on bacteriological culture of all bulk tank milk samples collected annually as part of the mandatory Danish S. agalactiae surveillance scheme, were extracted from the Danish Cattle Database and subsequently analysed. There was an increasing trend in both the incidence and prevalence of S. agalactiae over the study period. Per 100 herd-years the value of β was 54.1 (95% confidence interval [CI] 46.0-63.7); entry rate 0.3 (95% CI 0.2-0.4); infection-related exit rate 7.1 (95% CI 5.6-8.9); non-infection related exit rate 9.2 (95% CI 7.4-11.5) and recovery rate 40.0 (95% CI 36.8-43.5). This study demonstrates a need to tighten the current controls against S. agalactiae in order to lower its incidence. PMID:22560559

  10. Spatial patterns in surveillance data during control of Salmonella Dublin in bovine dairy herds in Jutland, Denmark 2003-2009.

    PubMed

    Ersbøll, Annette Kjær; Nielsen, Liza Rosenbaum

    2011-09-01

    Salmonella Dublin is the most commonly isolated Salmonella serotype in Danish cattle and leads to economic and welfare losses in infected herds. Furthermore, it leads to high mortality in human cases. A national surveillance program for Salmonella Dublin was initiated in Denmark in October 2002. This study aimed at modelling the progress and spatial patterns during the control of Salmonella Dublin in dairy herds in the Jutland peninsula in Denmark, especially differences between regions and years. A total of 6331 dairy herds were included during 2003-2009. Antibody measurements of bulk-tank milk samples were used for testing herd-level Salmonella status in these dairy herds. Risk maps were estimated as prevalence intensity maps. Spatial clustering was analysed using scan statistics and SMR was estimated. In 2003, the prevalence of Salmonella Dublin test-positive dairy herds was 24%. It decreased to 12% in 2009. Prevalence intensity maps showed large differences in the reduction of Salmonella Dublin test-positive herds. The number of clusters reduced during the study period. However, throughout the study period two clusters remained significant. Differences were seen in the progress of the control between regions over the years. The implementation and effectiveness of the control program was different between regions. The progress of control was seen to vary not only between regions, but also over time influencing infection dynamics. Thus, recommendations and regionally targeted efforts during control campaigns are needed.

  11. A mathematical model of Staphylococcus aureus control in dairy herds.

    PubMed Central

    Zadoks, R. N.; Allore, H. G.; Hagenaars, T. J.; Barkema, H. W.; Schukken, Y. H.

    2002-01-01

    An ordinary differential equation model was developed to simulate dynamics of Staphylococcus aureus mastitis. Data to estimate model parameters were obtained from an 18-month observational study in three commercial dairy herds. A deterministic simulation model was constructed to estimate values of the basic (R0) and effective (Rt) reproductive number in each herd, and to examine the effect of management on mastitis control. In all herds R0 was below the threshold value 1, indicating control of contagious transmission. Rt was higher than R0 because recovered individuals were more susceptible to infection than individuals without prior infection history. Disease dynamics in two herds were well described by the model. Treatment of subclinical mastitis and prevention of influx of infected individuals contributed to decrease of S. aureus prevalence. For one herd, the model failed to mimic field observations. Explanations for the discrepancy are given in a discussion of current knowledge and model assumptions. PMID:12403116

  12. Connectedness among herds of beef cattle bred under natural service

    PubMed Central

    2010-01-01

    Background A procedure to measure connectedness among herds was applied to a beef cattle population bred by natural service. It consists of two steps: (a) computing coefficients of determination (CDs) of comparisons among herds; and (b) building sets of connected herds. Methods The CDs of comparisons among herds were calculated using a sampling-based method that estimates empirical variances of true and predicted breeding values from a simulated n-sample. Once the CD matrix was estimated, a clustering method that can handle a large number of comparisons was applied to build compact clusters of connected herds of the Bruna dels Pirineus beef cattle. Since in this breed, natural service is predominant and there are almost no links with reference sires, to estimate CDs, an animal model was used taking into consideration all pedigree information and, especially, the connections with dams. A sensitivity analysis was performed to contrast single-trait sire and animal model evaluations with different heritabilities, multiple-trait animal model evaluations with different degrees of genetic correlations and models with maternal effects. Results Using a sire model, the percentage of connected herds was very low even for highly heritable traits whereas with an animal model, most of the herds of the breed were well connected and high CD values were obtained among them, especially for highly heritable traits (the mean of average CD per herd was 0.535 for a simulated heritability of 0.40). For the lowly heritable traits, the average CD increased from 0.310 in the single-trait evaluation to 0.319 and 0.354 in the multi-trait evaluation with moderate and high genetic correlations, respectively. In models with maternal effects, the average CD per herd for the direct effects was similar to that from single-trait evaluations. For the maternal effects, the average CD per herd increased if the maternal effects had a high genetic correlation with the direct effects, but the percentage

  13. Diversity of Listeria monocytogenes within a U.S. dairy herd, 2004-2010.

    PubMed

    Haley, Bradd J; Sonnier, Jakeitha; Schukken, Ynte H; Karns, Jeffrey S; Van Kessel, Jo Ann S

    2015-10-01

    Listeria monocytogenes, the causative agent of listeriosis, is frequently isolated from the environment. Dairy cows and dairy farm environments are reservoirs of this pathogen, where fecal shedding contributes to its environmental dispersal and contamination of milk, dairy products, and meat. The molecular diversity of 40 L. monocytogenes isolates representing 3 serogroups (1/2a, 1/2b, and 4b) collected between 2004 and 2010 from the feces of dairy cattle on a single dairy farm was assessed using a multivirulence locus sequence typing (MVLST) assay. The dairy farm L. monocytogenes MVLST patterns were compared to those from 138 strains isolated globally from clinical cases, foods, and the environment. Results of the study demonstrated that several distantly related L. monocytogenes strains persisted among members of the herd over the course of the study while other strains were transient. Furthermore, some strains isolated during this study appear to be distantly related to previously isolated L. monocytogenes while others are closely related to Epidemic Clones associated with human illness. This work demonstrates that dairy cows can be reservoirs of a diverse population of potentially human pathogenic L. monocytogenes that represents a risk to consumers of milk, dairy products, and meat.

  14. Prevalence of verotoxin-producing Escherichia coli (VTEC) 0157 in Swedish dairy herds.

    PubMed Central

    Eriksson, E.; Aspan, A.; Gunnarsson, A.; Vågsholm, I.

    2005-01-01

    A prevalence study of verotoxin-producing Escherichia coli O157 (VTEC O157) was performed in 371 randomly selected dairy herds distributed throughout Sweden. Faecal and manure samples were collected and analysed by immunomagnetic separation and culturing. Data were recorded for each herd regarding herd size, age of sampled animals and whether, in addition to cattle, the farm kept other animals. VTEC O157 was isolated from 33 (8.9%) of the 371 investigated herds. The prevalence was higher (23.3%) in Halland county than in the rest of Sweden (P > 0.01). Halland was also the county in Sweden that during the study period had the highest incidence of human VTEC O157 cases. VTEC O157 was not detected on any farm in northern Sweden. Identified risk factors, in the multivariate analyses, for herds being VTEC O157 positive were herd size, geographical localization, presence of pigs on the farm and median age of sampled animals. PMID:15816162

  15. Herd-level prevalence of Map infection in dairy herds of southern Chile determined by culture of environmental fecal samples and bulk-tank milk qPCR.

    PubMed

    Kruze, J; Monti, G; Schulze, F; Mella, A; Leiva, S

    2013-09-01

    Paratuberculosis, an infectious disease of domestic and wild ruminants caused by Mycobacterium avium subsp. paratuberculosis (Map), is an economically important disease in dairy herds worldwide. In Chile the disease has been reported in domestic and wildlife animals. However, accurate and updated estimations of the herd-prevalence in cattle at national or regional level are not available. The objectives of this study were to determine the herd-level prevalence of dairy herds with Map infected animals of Southern Chile, based on two diagnostic tests: culture of environmental fecal samples and bulk-tank milk qPCR. Two composite environmental fecal samples and one bulk-tank milk sample were collected during September 2010 and September 2011 from 150 dairy farms in Southern Chile. Isolation of Map from environmental fecal samples was done by culture of decontaminated samples on a commercial Herrold's Egg Yolk Medium (HEYM) with and without mycobactin J. Suspicious colonies were confirmed to be Map by conventional IS900 PCR. Map detection in bulk-tank milk samples was done by real time IS900 PCR assay. PCR-confirmed Map was isolated from 58 (19.3%) of 300 environmental fecal samples. Holding pens and manure storage lagoons were the two more frequent sites found positive for Map, representing 35% and 33% of total positive samples, respectively. However, parlor exits and cow alleyways were the two sites with the highest proportion of positive samples (40% and 32%, respectively). Herd prevalence based on environmental fecal culture was 27% (true prevalence 44%) compared to 49% (true prevalence 87%) based on bulk-tank milk real time IS900 PC. In both cases herd prevalence was higher in large herds (>200 cows). These results confirm that Map infection is wide spread in dairy herds in Southern Chile with a rough herd-level prevalence of 28-100% depending on the herd size, and that IS900 PCR on bulk-tank milk samples is more sensitive than environmental fecal culture to detect

  16. Brucellosis in Dairy Cattle and Goats in Northern Ecuador

    PubMed Central

    Poulsen, Keith P.; Hutchins, Frank T.; McNulty, Chase M.; Tremblay, Marlène; Zabala, Carmen; Barragan, Veronica; Lopez, Luis; Trueba, Gabriel; Bethel, Jeffrey W.

    2014-01-01

    The purpose of this study was to conduct a convenience study for brucellosis prevalence in dairy-producing animals in northern Ecuador. In total, 2,561 cows and 301 goats were tested. Cattle sera were tested using the Rose Bengal card antigen test (RBCT), yielding an overall apparent prevalence of 5.5% (95% confidence interval [95% CI] = 4.7–6.5%) and true prevalence of 7.2% (95% CI = 6.0–8.5%). Prevalence varied by herd size and was highest in larger commercial herds. Polymerase chain reaction was used to test goat milk and lymph nodes, resulting in 9% and 8% positivity, respectively. The RBCTs from goat sera yielded an adjusted true prevalence of 17.8% (95% CI = 6.2–44.2%). Our findings are similar to other overall prevalence estimates for dairy herds but show higher prevalence in commercial herds compared with small groups (less than five animals). We also identify urban milking goats living in metropolitan Quito as a potential source of zoonosis. PMID:24591429

  17. Within-herd prevalence thresholds for the detection of Mycobacterium avium subspecies paratuberculosis-positive dairy herds using boot swabs and liquid manure samples.

    PubMed

    Donat, K; Hahn, N; Eisenberg, T; Schlez, K; Köhler, H; Wolter, W; Rohde, M; Pützschel, R; Rösler, U; Failing, K; Zschöck, P M

    2016-01-01

    The control of Johne's disease requires the identification of Mycobacterium avium ssp. paratuberculosis (MAP)-positive herds. Boot swabs and liquid manure samples have been suggested as an easy-to-use alternative to sampling individual animals in order to diagnose subclinical Johne's disease at the herd level, but there is a need to evaluate performance of this approach in the field. Using a logistic regression model, this study aimed to calculate the threshold level of the apparent within-herd prevalence as determined by individual faecal culture, thus allowing the detection of whether a herd is MAP positive. A total of 77 boot swabs and 75 liquid manure samples were taken from 19 certified negative and 58 positive dairy herds. Faecal culture, three different polymerase chain reaction (PCR) methods and the combination of faecal culture with PCR were applied in order to detect MAP. For 50% probability of detection, a within-herd prevalence threshold of 1·5% was calculated for testing both matrices simultaneously by faecal culture and PCR, with the threshold increased to 4·0% for 90% probability of detection. The results encourage the use of boot swabs or liquid manure samples, or a combination both, for identifying MAP-positive herds and, to a certain extent, for monitoring certified Johne's disease-negative cattle herds.

  18. Responses to diagnostic tests for bovine tuberculosis in dairy and non-dairy cattle naturally exposed to Mycobacterium bovis in Great Britain.

    PubMed

    Downs, S H; Broughan, J M; Goodchild, A V; Upton, P A; Durr, P A

    2016-10-01

    Field surveillance of British cattle using the single intradermal comparative cervical tuberculin (SICCT) test shows a higher incidence rate of bovine tuberculosis (bTB) in dairy compared to beef herds, but a lower probability of post-mortem examination confirmed (PMC) Mycobacterium bovis infection in dairy herds. A cross-sectional study was conducted to compare animal level differences in bTB detection between dairy and non-dairy cattle in Great Britain. During the period from 2002 to 2005, 200 (41% dairy) reactors in the SICCT test (standard interpretation) were randomly selected, and 200 in-contact cattle (43% dairy) were purposively selected from bTB-infected herds. Interferon (IFN)-γ responses in blood to bovine and avian purified protein derivative (PPD), and early secretory antigen target 6 kDa and culture filtrate protein 10 (ESAT-6/CFP10), were measured. The post-mortem examination included gross pathological examination, mycobacterial culture and histopathology. The proportions of cattle positive to ESAT6/CFP10 were 26% (95% confidence interval, CI, 15-39%) in dairy reactors and 62% (95% CI 51-72%) in non-dairy reactors (P <0.001). PMC risk was 34% (95% CI 24-45%) in dairy reactors and 69% (95% CI 60-78%) in non-dairy reactors (P <0.001). The odds ratio for PMC risk in dairy reactors compared to non-dairy reactors, after controlling for bTB prevalence, herd size and SICCT test response, was 0.27 (95% CI 0.14-0.53; P <0.001). In surveillance data, adjusted animal level PMC risks were lower for dairy reactors than for beef reactors aged >2 years (P <0.001).

  19. Responses to diagnostic tests for bovine tuberculosis in dairy and non-dairy cattle naturally exposed to Mycobacterium bovis in Great Britain.

    PubMed

    Downs, S H; Broughan, J M; Goodchild, A V; Upton, P A; Durr, P A

    2016-10-01

    Field surveillance of British cattle using the single intradermal comparative cervical tuberculin (SICCT) test shows a higher incidence rate of bovine tuberculosis (bTB) in dairy compared to beef herds, but a lower probability of post-mortem examination confirmed (PMC) Mycobacterium bovis infection in dairy herds. A cross-sectional study was conducted to compare animal level differences in bTB detection between dairy and non-dairy cattle in Great Britain. During the period from 2002 to 2005, 200 (41% dairy) reactors in the SICCT test (standard interpretation) were randomly selected, and 200 in-contact cattle (43% dairy) were purposively selected from bTB-infected herds. Interferon (IFN)-γ responses in blood to bovine and avian purified protein derivative (PPD), and early secretory antigen target 6 kDa and culture filtrate protein 10 (ESAT-6/CFP10), were measured. The post-mortem examination included gross pathological examination, mycobacterial culture and histopathology. The proportions of cattle positive to ESAT6/CFP10 were 26% (95% confidence interval, CI, 15-39%) in dairy reactors and 62% (95% CI 51-72%) in non-dairy reactors (P <0.001). PMC risk was 34% (95% CI 24-45%) in dairy reactors and 69% (95% CI 60-78%) in non-dairy reactors (P <0.001). The odds ratio for PMC risk in dairy reactors compared to non-dairy reactors, after controlling for bTB prevalence, herd size and SICCT test response, was 0.27 (95% CI 0.14-0.53; P <0.001). In surveillance data, adjusted animal level PMC risks were lower for dairy reactors than for beef reactors aged >2 years (P <0.001). PMID:27687920

  20. Knowledge of Bovine Tuberculosis, Cattle Husbandry and Dairy Practices amongst Pastoralists and Small-Scale Dairy Farmers in Cameroon

    PubMed Central

    Kelly, Robert F.; Hamman, Saidou M.; Morgan, Kenton L.; Nkongho, Egbe F.; Ngwa, Victor Ngu; Tanya, Vincent; Andu, Walters N.; Sander, Melissa; Ndip, Lucy; Handel, Ian G.; Mazeri, Stella; Muwonge, Adrian; Bronsvoort, Barend M. de. C.

    2016-01-01

    Background Control of bovine tuberculosis (bTB) and zoonotic tuberculosis (zTB) has relied upon surveillance and slaughter of infected cattle, milk pasteurisation and public health education. In Cameroon, like many other sub-Saharan African countries, there is limited understanding of current cattle husbandry or milk processing practices or livestock keepers awareness of bTB. This paper describes husbandry and milk processing practices within different Cameroonian cattle keeping communities and bTB awareness in comparison to other infectious diseases. Study design A population based cross-sectional sample of herdsmen and a questionnaire were used to gather data from pastoralists and dairy farmers in the North West Region and Vina Division of Cameroon. Results Pastoralists were predominately male Fulanis who had kept cattle for over a decade. Dairy farmers were non-Fulani and nearly half were female. Pastoralists went on transhumance with their cattle and came into contact with other herds and potential wildlife reservoirs of bTB. Dairy farmers housed their cattle and had little contact with other herds or wildlife. Pastoralists were aware of bTB and other infectious diseases such as foot-and-mouth disease and fasciolosis. These pastoralists were also able to identify clinical signs of these diseases. A similar proportion of dairy farmers were aware of bTB but fewer were aware of foot-and-mouth and fasciolosis. In general, dairy farmers were unable to identify any clinical signs for any of these diseases. Importantly most pastoralists and dairy farmers were unaware that bTB could be transmitted to people by consuming milk. Conclusions Current cattle husbandry practices make the control of bTB in cattle challenging especially in mobile pastoralist herds. Routine test and slaughter control in dairy herds would be tractable but would have profound impact on dairy farmer livelihoods. Prevention of transmission in milk offers the best approach for human risk mitigation

  1. Epidemiology and impact of Fasciola hepatica exposure in high-yielding dairy herds

    PubMed Central

    Howell, Alison; Baylis, Matthew; Smith, Rob; Pinchbeck, Gina; Williams, Diana

    2015-01-01

    The liver fluke Fasciola hepatica is a trematode parasite with a worldwide distribution and is the cause of important production losses in the dairy industry. The aim of this observational study was to assess the prevalence of exposure to F. hepatica in a group of high yielding dairy herds, to determine the risk factors and investigate their associations with production and fertility parameters. Bulk milk tank samples from 606 herds that supply a single retailer with liquid milk were tested with an antibody ELISA for F. hepatica. Multivariable linear regression was used to investigate the effect of farm management and environmental risk factors on F. hepatica exposure. Higher rainfall, grazing boggy pasture, presence of beef cattle on farm, access to a stream or pond and smaller herd size were associated with an increased risk of exposure. Univariable regression was used to look for associations between fluke exposure and production-related variables including milk yield, composition, somatic cell count and calving index. Although causation cannot be assumed, a significant (p < 0.001) negative association was seen between F. hepatica exposure and estimated milk yield at the herd level, representing a 15% decrease in yield for an increase in F. hepatica exposure from the 25th to the 75th percentile. This remained significant when fertility, farm management and environmental factors were controlled for. No associations were found between F. hepatica exposure and any of the other production, disease or fertility variables. PMID:26093971

  2. Epidemiology and impact of Fasciola hepatica exposure in high-yielding dairy herds.

    PubMed

    Howell, Alison; Baylis, Matthew; Smith, Rob; Pinchbeck, Gina; Williams, Diana

    2015-09-01

    The liver fluke Fasciola hepatica is a trematode parasite with a worldwide distribution and is the cause of important production losses in the dairy industry. The aim of this observational study was to assess the prevalence of exposure to F. hepatica in a group of high yielding dairy herds, to determine the risk factors and investigate their associations with production and fertility parameters. Bulk milk tank samples from 606 herds that supply a single retailer with liquid milk were tested with an antibody ELISA for F. hepatica. Multivariable linear regression was used to investigate the effect of farm management and environmental risk factors on F. hepatica exposure. Higher rainfall, grazing boggy pasture, presence of beef cattle on farm, access to a stream or pond and smaller herd size were associated with an increased risk of exposure. Univariable regression was used to look for associations between fluke exposure and production-related variables including milk yield, composition, somatic cell count and calving index. Although causation cannot be assumed, a significant (p<0.001) negative association was seen between F. hepatica exposure and estimated milk yield at the herd level, representing a 15% decrease in yield for an increase in F. hepatica exposure from the 25th to the 75th percentile. This remained significant when fertility, farm management and environmental factors were controlled for. No associations were found between F. hepatica exposure and any of the other production, disease or fertility variables.

  3. A survey on Dictyocaulus viviparus antibodies in bulk milk of dairy herds in Northern Germany.

    PubMed

    Klewer, Anne-Marie; Forbes, Andrew; Schnieder, Thomas; Strube, Christina

    2012-02-01

    Parasitic bronchitis caused by the bovine lungworm, Dictyocaulus viviparus, occurs worldwide in temperate areas. The parasite is found predominantly in calves and heifers, but dairy cattle can suffer from lungworms when they become infected for the first time or if they have lost immunity due to lack of exposure to lungworm larvae during the grazing season. The present study was performed to determine the D. viviparus bulk milk antibody prevalence in dairy herds in the East Frisian region of northwestern Germany, Lower Saxony, by analysing bulk milk samples collected in January (860 samples), September (866 samples) and November (860 samples) 2008, thereby representing 906 dairy farms. These samples were tested for antibodies against D. viviparus by a milk ELISA. This test detects patent infections only since it is based on recombinant major sperm protein as antigen. While in January 12.8% of dairy farms were positive for D. viviparus antibodies, the bulk milk samples collected in September and November revealed 6.9% and 6.6% positive dairy herds. From the 906 dairy farms included in the study, 191 (21.1%) tested positive at least once for antibodies against lungworm. From 810 dairy farms from which bulk milk samples were obtained during all three samplings, 146 (18.0%) farms were positive at one sampling date, 27 (3.3%) at two, and 4 (0.5%) on all three sampling dates. The majority of the farms represented in the study belonged to four districts of East Frisia, which showed no significant difference in the proportion of positive dairy farms.

  4. Survey of facility and management characteristics of large, Upper Midwest dairy herds clustered by Dairy Herd Improvement records.

    PubMed

    Brotzman, R L; Döpfer, D; Foy, M R; Hess, J P; Nordlund, K V; Bennett, T B; Cook, N B

    2015-11-01

    A survey of management practices was conducted to investigate potential associations with groupings of herds formed by cluster analysis (CA) of Dairy Herd Improvement (DHI) data of 557 Upper Midwest herds of 200 cows or greater. Differences in herd management practices were identified between the groups, despite underlying similarities; for example, freestall housing and milking in a parlor. Group 6 comprised larger herds with a high proportion of primiparous cows and most frequently utilized practices promoting increased production [e.g., 84.4% used recombinant bovine somatotropin (rbST)], decreased lameness (e.g., 96.9% used routine hoof trimming for cows), and improved efficiency in reproduction [e.g., 93.8% synchronized the first breeding in cows (SYNCH)] and labor (e.g., mean ± SD, 67 ± 19 cows per 50-h per week full-time equivalent worker). Group 1 had the best mean DHI performances and followed most closely group 6 for the rate of adoption of intensive management practices while tending to outperform group 6 despite a generally smaller mean herd size (e.g., 42.3 ± 3.6 kg vs. 39.9 ± 3.6 kg of energy-corrected milk production; 608 ± 352 cows vs. 1,716 ± 1,405 cows). Group 2 were smaller herds with relatively high levels of performance that used less intensive management (e.g., 100% milked twice daily) and less technology (33.3 vs. 73.0% of group 1 used rbST). Group 4 were smaller but poorer-performing herds with low turnover and least frequently used intensive management practices (e.g., 39.1% SYNCH; 30.4% allowed mature, high-producing cows access to pasture). Group 5 used modern technologies and practices associated with improved production, yet had the least desirable mean DHI performance of all 6 groups. This group had the lowest proportion of deep loose-bedded stalls (only 52.2% used sand bedding) and the highest proportion (34.8%) of herds not using routine hoof trimming. The survey of group 3 herds did not reveal strong trends in management. The

  5. Environmental contamination with Mycobacterium avium subsp. paratuberculosis in endemically infected dairy herds.

    PubMed

    Smith, R L; Schukken, Y H; Pradhan, A K; Smith, J M; Whitlock, R H; Van Kessel, J S; Wolfgang, D R; Grohn, Y T

    2011-10-01

    Environmental contamination with Mycobacterium avium subsp. paratuberculosis (MAP) is thought to be one of the primary sources of infection for dairy cattle. The exact link between fecal shedding of MAP by individual cows and environmental contamination levels at the herd level was explored with a cross-sectional analysis of longitudinally collected samples on 3 dairy farms. Composite samples from multiple environmental sites in 3 commercial dairy herds in the Northeast US were cultured quarterly for MAP, providing 1131 samples (133 (11.8%) were culture-positive), and all adult animals in the herds were tested biannually by fecal culture (FC), for 6 years. Of the environmental sites sampled, manure storage areas and shared alleyways were most likely to be culture-positive. Environmental sample results were compared to FC results from either the concurrent or previous sampling date at both the herd and the pen level. At the herd level, a 1 log unit increase in average fecal shedding increased the odds of a positive non-pen environmental sample by a factor of 6 and increased the average amount of MAP in non-pen samples by 2.9 cfu/g. At the pen level, a 1 log unit increase in average fecal shedding in the pen increased the odds of a positive environment by a factor of 2.4 and the average amount of MAP was increased by 3.5 cfu/g. We were not able to model the relationship between non-pen environmental sample status and the distance between shedding animals and the sample's location, and neighboring pens did not significantly affect the results of the pen-level analysis. The amount of MAP in pen-level samples and the probability of a pen testing positive for MAP were both positively but non-significantly correlated with the number of animals in the pen shedding >30 cfu/g of MAP. At least 6 environmental samples met the criteria for the U.S. Voluntary Bovine Johne's Disease Control Program on 47 of the 72 sampling dates; of these, 19 of the 47 FC-positive sampling dates

  6. Spatiotemporal patterns, annual baseline and movement-related incidence of Streptococcus agalactiae infection in Danish dairy herds: 2000-2009.

    PubMed

    Mweu, Marshal M; Nielsen, Søren S; Halasa, Tariq; Toft, Nils

    2014-02-01

    Several decades after the inception of the five-point plan for the control of contagious mastitis pathogens, Streptococcus agalactiae (S. agalactiae) persists as a fundamental threat to the dairy industry in many countries. A better understanding of the relative importance of within- and between-herd sources of new herd infections coupled with the spatiotemporal distribution of the infection, may aid in effective targeting of control efforts. Thus, the objectives of this study were: (1) to describe the spatiotemporal patterns of infection with S. agalactiae in the population of Danish dairy herds from 2000 to 2009 and (2) to estimate the annual herd-level baseline and movement-related incidence risks of S. agalactiae infection over the 10-year period. The analysis involved registry data on bacteriological culture of all bulk tank milk samples collected as part of the mandatory Danish S. agalactiae surveillance scheme as well as live cattle movements into dairy herds during the specified 10-year period. The results indicated that the predicted risk of a herd becoming infected with S. agalactiae varied spatiotemporally; the risk being more homogeneous and higher in the period after 2005. Additionally, the annual baseline risks yielded significant yet distinctive patterns before and after 2005 - the risk of infection being higher in the latter phase. On the contrary, the annual movement-related risks revealed a non-significant pattern over the 10-year period. There was neither evidence for spatial clustering of cases relative to the population of herds at risk nor spatial dependency between herds. Nevertheless, the results signal a need to beef up within-herd biosecurity in order to reduce the risk of new herd infections. PMID:24269038

  7. Factors affecting calf mortality in Iranian Holstein dairy herds.

    PubMed

    Azizzadeh, Mohammad; Shooroki, Hadi Fazeli; Kamalabadi, Ali Shafiee; Stevenson, Mark A

    2012-05-01

    The objective of this study was to document mortality reasons and risk factors for mortality in dairy calves in the northeast of Iran. This was a prospective cohort study of calves born on ten commercial dairy herds from 21 March 2009 to 20 March 2010. A total of 4097 live calves were followed for 90 days after birth. For each calf details of sex, parity of the dam, type of parturition and season of birth were recorded. The interval (in days) from the date of birth to the date of death and the reason for death was recorded for those calves that died before 90 days of age. A Cox proportional hazards model, including a frailty term to account for unmeasured herd-level effects was developed to quantify the effect of factors associated with time to death. Two hundred and sixty-six (6.5%, 95% CI: 5.8-7.3%) of the 4097 live-born calves died or were euthanised before 90 days of age. The most important reasons for death were digestive tract disorders (58% of all deaths, 95% CI: 52-64%) followed by respiratory diseases (13% of all deaths, 95% CI: 9-17%). Calves exposed to dystocia at birth had 2.09 (95% CI: 1.49-2.92) times the daily hazard of death compared with calves born from a normal calving. The daily hazard of death for calves born in the summer was 1.93 (95% CI: 1.41-2.64) times greater than the hazard for those calves born in the autumn. Inclusion of the herd-level frailty term had a significant effect on hazard estimates indicating that the study herds were heterogeneous in the distribution of unmeasured herd-level factors influencing calf survival. Our results show that diarrhoea is the most important cause of calf mortality in dairy herds in this area of Iran and that environmental and management factors affect calf mortality rate.

  8. Herd-level risk factors for bovine tuberculosis in French cattle herds.

    PubMed

    Marsot, Maud; Béral, Marina; Scoizec, Axelle; Mathevon, Yoann; Durand, Benoit; Courcoul, Aurélie

    2016-09-01

    Although officially free of bovine tuberculosis (bTB), France has been experiencing a slight increase in the incidence and geographical spread of the infection. Eradication of bTB requires determining the infection risk factors. Although several studies identifying bTB risk factors have been conducted in the United Kingdom and Spain, no information is currently available regarding bTB risk factors in French cattle. The objective of this work was thus to study the factors associated with the risk of bTB in cattle herds in three French administrative divisions (départements of Ardennes, Côte d'Or and Dordogne). A case-control study was conducted to compare herds having experienced a bTB outbreak between 2012 and early 2014 with randomly selected control herds of the three study départements. A questionnaire of farming practices, inter-herd contacts (e.g. at pasture or via vehicles or materials), and the presence of other domestic species was carried out in the selected herds. Data on other variables of interest included animal movements between farms and potential contacts between cattle and wildlife (e.g. badger and wild boar abundances) were also collected. Multivariable logistic regression and multimodel inference methods were used to assess risk factors related to bTB. A total of 216 herds (72 cases and 144 controls) were analyzed. The two main risk factors were the presence of a recent neighboring outbreak, being defined as a neighboring herd at pasture reported as infected in the past two years (odds ratio (OR)=3.6; population attributable fraction (PAF)=30.7%) and the presence of a farm building for cattle housing or for feed storage located at more than 300-m from inhabited areas (OR=2.3; PAF=27.6%). Another risk factor was related to sharing water points at pasture with a recent neighboring outbreak. Results illustrated the multifactorial nature of bTB dynamics. The risk factors related to recently infected neighboring herds could be attributable to

  9. Herd-level risk factors for bovine tuberculosis in French cattle herds.

    PubMed

    Marsot, Maud; Béral, Marina; Scoizec, Axelle; Mathevon, Yoann; Durand, Benoit; Courcoul, Aurélie

    2016-09-01

    Although officially free of bovine tuberculosis (bTB), France has been experiencing a slight increase in the incidence and geographical spread of the infection. Eradication of bTB requires determining the infection risk factors. Although several studies identifying bTB risk factors have been conducted in the United Kingdom and Spain, no information is currently available regarding bTB risk factors in French cattle. The objective of this work was thus to study the factors associated with the risk of bTB in cattle herds in three French administrative divisions (départements of Ardennes, Côte d'Or and Dordogne). A case-control study was conducted to compare herds having experienced a bTB outbreak between 2012 and early 2014 with randomly selected control herds of the three study départements. A questionnaire of farming practices, inter-herd contacts (e.g. at pasture or via vehicles or materials), and the presence of other domestic species was carried out in the selected herds. Data on other variables of interest included animal movements between farms and potential contacts between cattle and wildlife (e.g. badger and wild boar abundances) were also collected. Multivariable logistic regression and multimodel inference methods were used to assess risk factors related to bTB. A total of 216 herds (72 cases and 144 controls) were analyzed. The two main risk factors were the presence of a recent neighboring outbreak, being defined as a neighboring herd at pasture reported as infected in the past two years (odds ratio (OR)=3.6; population attributable fraction (PAF)=30.7%) and the presence of a farm building for cattle housing or for feed storage located at more than 300-m from inhabited areas (OR=2.3; PAF=27.6%). Another risk factor was related to sharing water points at pasture with a recent neighboring outbreak. Results illustrated the multifactorial nature of bTB dynamics. The risk factors related to recently infected neighboring herds could be attributable to

  10. Clostridium botulinum in cattle and dairy products.

    PubMed

    Lindström, Miia; Myllykoski, Jan; Sivelä, Seppo; Korkeala, Hannu

    2010-04-01

    The use of plastic-wrapped and nonacidified silage as cattle feed has led to an increasing number of botulism outbreaks due to Clostridium botulinum Groups I-III in dairy cattle. The involvement of Groups I and II organisms in cattle botulism has raised concern of human botulism risk associated with the consumption of dairy products. Multiplication of C. botulinum in silage and in the gastrointestinal tract of cattle with botulism has been reported, thus contamination of the farm environment and raw milk, and further transmission through the dairy chain, are possible. The standard milk pasteurization treatment does not eliminate spores, and the intrinsic factors of many dairy products allow botulinal growth and toxin production. Although rare, several large botulism outbreaks due to both commercial and home-prepared dairy products have been reported. Factors explaining these outbreaks include most importantly temperature abuse, but also unsafe formulation, inadequate fermentation, insufficient thermal processing, post-process contamination, and lack of adequate quality control for adjunct ingredients were involved. The small number of outbreaks is probably explained by a low incidence of spores in milk, the presence of competitive bacteria in pasteurized milk and other dairy products, and growth-inhibitory combinations of intrinsic and extrinsic factors in cultured and processed dairy products.

  11. Clostridium botulinum in cattle and dairy products.

    PubMed

    Lindström, Miia; Myllykoski, Jan; Sivelä, Seppo; Korkeala, Hannu

    2010-04-01

    The use of plastic-wrapped and nonacidified silage as cattle feed has led to an increasing number of botulism outbreaks due to Clostridium botulinum Groups I-III in dairy cattle. The involvement of Groups I and II organisms in cattle botulism has raised concern of human botulism risk associated with the consumption of dairy products. Multiplication of C. botulinum in silage and in the gastrointestinal tract of cattle with botulism has been reported, thus contamination of the farm environment and raw milk, and further transmission through the dairy chain, are possible. The standard milk pasteurization treatment does not eliminate spores, and the intrinsic factors of many dairy products allow botulinal growth and toxin production. Although rare, several large botulism outbreaks due to both commercial and home-prepared dairy products have been reported. Factors explaining these outbreaks include most importantly temperature abuse, but also unsafe formulation, inadequate fermentation, insufficient thermal processing, post-process contamination, and lack of adequate quality control for adjunct ingredients were involved. The small number of outbreaks is probably explained by a low incidence of spores in milk, the presence of competitive bacteria in pasteurized milk and other dairy products, and growth-inhibitory combinations of intrinsic and extrinsic factors in cultured and processed dairy products. PMID:20301016

  12. Efficiency of dairy farms participating and not participating in veterinary herd health management programs.

    PubMed

    Derks, Marjolein; Hogeveen, Henk; Kooistra, Sake R; van Werven, Tine; Tauer, Loren W

    2014-12-01

    This paper compares farm efficiencies between dairies who were participating in a veterinary herd health management (VHHM) program with dairies not participating in such a program, to determine whether participation has an association with farm efficiency. In 2011, 572 dairy farmers received a questionnaire concerning the participation and execution of a VHHM program on their farms. Data from the questionnaire were combined with farm accountancy data from 2008 through 2012 from farms that used calendar year accounting periods, and were analyzed using Stochastic Frontier Analysis (SFA). Two separate models were specified: model 1 was the basic stochastic frontier model (output: total revenue; input: feed costs, land costs, cattle costs, non-operational costs), without explanatory variables embedded into the efficiency component of the error term. Model 2 was an expansion of model 1 which included explanatory variables (number of FTE; total kg milk delivered; price of concentrate; milk per hectare; cows per FTE; nutritional yield per hectare) inserted into the efficiency component of the joint error term. Both models were estimated with the financial parameters expressed per 100 kg fat and protein corrected milk and per cow. Land costs, cattle costs, feed costs and non-operational costs were statistically significant and positive in all models (P<0.01). Frequency distributions of the efficiency scores for the VHHM dairies and the non-VHHM dairies were plotted in a kernel density plot, and differences were tested using the Kolmogorov-Smirnov two-sample test. VHHM dairies had higher total revenue per cow, but not per 100 kg milk. For all SFA models, the difference in distribution was not statistically different between VHHM dairies and non-VHHM dairies (P values 0.94, 0.35, 0.95 and 0.89 for the basic and complete model per 100 kg fat and protein corrected milk and per cow respectively). Therefore we conclude that with our data farm participation in VHHM is not related

  13. Associations between nondietary factors and dairy herd performance.

    PubMed

    Bach, A; Valls, N; Solans, A; Torrent, T

    2008-08-01

    Forty-seven dairy herds (approximately 3,129 lactating cows) from northeast of Spain that were offering exactly the same lactating ration were surveyed to determine the effect of nondietary factors on herd performance. The survey collected information on the profile of the owners (their future intentions, the number of workers, and time devoted to the enterprise), information regarding the animals (reproductive performance, incidence of pathology, culling rate, etc.), information on the facilities (number of feeders, waters, stalls, cleanliness, etc.) and information on management practices (numbers of daily milkings, feed deliveries, feed push-ups, cleaning frequency, etc.). In addition, the chemical quality of drinking water from each dairy enterprise was determined. Also, amount of feed delivered to each herd, daily total milk production, and milk quality were obtained for each herd for a period of 8 mo before the fulfillment of the survey. Mortality rate of calves tended to be lesser in herds that weaned progressively than in those that weaned abruptly. Age at first calving was negatively correlated with level of milk production (mainly due to the type of heifer rearing system used). Culling rate tended to be lower in herds that used a close-up ration than in those that did not. Using gloves and paper towels (instead of cloth towels) tended to reduce the somatic cell count in milk. Concentration of calcium in the drinking water tended to be negatively correlated with the number of days open and with the proportion of cows culled due to infertility problems. Despite that the 47 herds fed the same ration and shared a similar genetic base, average milk production per cow ranged from 20.6 to 33.8 kg/d. A positive relationship (r = 0.57) between the number of stalls per cow and milk production was found. The most important nondietary factors that affected milk production in these dairy herds were age at first calving, presence or absence of feed refusals, number of

  14. Coxiella burnetii seroprevalence and associated risk factors in dairy and mixed cattle farms from Ecuador.

    PubMed

    Carbonero, Alfonso; Guzmán, Lucía T; Montaño, Karen; Torralbo, Alicia; Arenas-Montes, Antonio; Saa, Luis R

    2015-03-01

    Q fever is a zoonotic disease caused by Coxiella burnetii, a bacterial agent for which ruminants are the main reservoir. An extensive cross-sectional study to determine the seroprevalence of and associated risk factors for Q fever was performed in dairy and mixed (dairy-beef) cattle herds in Ecuador. A total of 2668 serum samples from 386 herds were analyzed using an ELISA. In addition, a questionnaire with 57 variables related to management, feeding, facilities, biosecurity and animal health was completed for every cattle farm. A Generalized Estimating Equations model was used to determine the factors associated with C. burnetii seropositivity. The true prevalence of C. burnetii seropositivity in dairy and mixed cattle from Ecuador reached 12.6% (CI95%: 11.3-13.9%). The herd prevalence was 46.9% (181/386) (CI95%: 41.9-51.9%), and the within herd prevalence ranged between 8% and 100% (mean: 25.0%; Q1: 12.5%, Q2: 25.0%, Q3: 37.5%). Four factors were included in the GEE model for C. burnetii seropositivity: age of the cattle (OR: 1.01; CI95%: 1.006-1.014), feeding of calves with milk replacers (OR: 1.94; CI95%: 1.1-3.3), bovine respiratory syncytial virus seropositivity (OR: 1.54; CI95%: 1.1-2.3), and disinfection of the umbilical cord (OR: 0.60; CI95%: 0.4-0.9).

  15. Herd health and management of dairy cow

    NASA Astrophysics Data System (ADS)

    Ćaǧlayan, Alper; Yüca, Songül

    2016-04-01

    Herd management requires multidisciplinary practices including animal feeding, gynecology, artificial insemination, immunology, and similar topics. Animal feeding is the most delicate subject as the fodder expense is 70% of the farm cost and as nearly all of the metabolic diseases arising out as health problem are because of misfeeding. However, a business organization's being able to maintain making profit will be possible by taking a healthy calf from breeding herd every year. For this reason, precision registrations of birth and artificial insemination, following-up pregnant state of animals, and making the other animals pregnant as soon as possible should be primary aim. It should not be forgotten that diarrhea and pneumonia in calves are among the most frequently witnessed infection related health problems. Mastitis, metritis and foot diseases take an important place in mature cows. These diseases can be minimized by vaccinations that are done properly and in suitable time, in-service training of staffs, making shelters suitable for animals welfare, and improving the hygienic conditions.

  16. Benchmarking dairy herd health status using routinely recorded herd summary data

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Genetic improvement of dairy cattle health through the use of producer-recorded data has been determined to be feasible. Low estimated heritabilities indicate that genetic progress will be slow. Variation observed in lowly heritable traits can largely be attributed to non-genetic factors, such as th...

  17. Reproductive Systems for North American Beef Cattle Herds.

    PubMed

    Larson, Robert L; White, Brad J

    2016-07-01

    A systems approach to beef cattle reproduction facilitates evaluating the flow of cattle through the herd population based on temporal changes in reproductive and production state. The previous years' timing of calving has either a positive or negative effect on the present year's reproductive success. In order to create and maintain high reproductive success, one must focus on: developing heifers to become pregnant early in the breeding season, ensuring bull breeding soundness, aligning the calving period with optimal resource availability, managing forage and supplementation to ensure good cow body condition going into calving, and minimizing reproductive losses due to disease. PMID:27156223

  18. Herd-level risk factors associated with fecal shedding of Shiga toxin-encoding bacteria on dairy farms in Minnesota, USA.

    PubMed

    Cho, Seongbeom; Fossler, Charles P; Diez-Gonzalez, Francisco; Wells, Scott J; Hedberg, Craig W; Kaneene, John B; Ruegg, Pamela L; Warnick, Lorin D; Bender, Jeffrey B

    2013-07-01

    This study aimed to identify herd-level risk factors associated with fecal shedding of Shiga toxin-encoding bacteria (STB) on dairy cattle farms in Minnesota, USA. After adjustment for farm size, risk factors included: use of total mixed ration (TMR) for lactating dairy cows [odds ratio (OR) = 3.0; 95% confidence interval (CI): 1.8 to 5.1], no use of monensin for weaned calves (OR = 4.8, 95% CI: 2.5, 9.3), and no use of decoquinate for preweaned calves (OR = 2.2, 95% CI: 1.4, 3.6). Fecal shedding of STB was more common in small herds (< 100 cows, OR = 3.6, 95% CI: 2.1, 6.2) than in large herds (≥ 100 cows). Herd management factors related to cattle feeding practices were associated with fecal shedding of STB.

  19. Bovine herpesvirus type 1 (BHV-1) and bovine viral diarrhoea virus (BVDV) infections in dairy herds: self clearance and the detection of seroconversions against a new atypical pestivirus.

    PubMed

    Kampa, Jaruwan; Alenius, Stefan; Emanuelson, Ulf; Chanlun, Aran; Aiumlamai, Suneerat

    2009-11-01

    The epidemiology of bovine herpesvirus type 1 (BHV-1) and bovine viral diarrhoea virus (BVDV) was studied in a population of small dairy herds that had not been vaccinated. Bulk tank milk samples of 186 herds in Thailand were collected four times between 2002 and 2004. Serum samples from individual animals in 11 herds were also taken on three occasions. The prevalence of BHV-1 in the 186 herds was 61% in 2002, decreasing to 48% in 2004 and for BVDV was 91% in 2002, decreasing to 72% in 2004. A BVDV antigen-positive calf was found in one of the 11 herds, and animals in this herd and three other herds seroconverted to a recently described atypical BVDV strain (HoBi). This study showed a significantly decreasing prevalence for both BHV-1 and BVDV due to a self-clearance process. Further studies are needed to find out how the atypical BVDV strain entered the cattle population.

  20. Stochastic modeling of imperfect Salmonella vaccines in an adult dairy herd.

    PubMed

    Lu, Zhao; Gröhn, Yrjö T; Smith, Rebecca L; Karns, Jeffrey S; Hovingh, Ernest; Schukken, Ynte H

    2014-03-01

    Salmonella is a major cause of bacterial foodborne disease. Human salmonellosis results in significant public health concerns and a considerable economic burden. Dairy cattle are recognized as a key source of several Salmonella serovars that are a threat to human health. To lower the risk of Salmonella infection, reduction of Salmonella prevalence in dairy cattle is important. Vaccination as a control measure has been applied for reduction of preharvest Salmonella prevalence on dairy farms. Salmonella vaccines are usually imperfect (i.e., vaccines may provide a partial protection for susceptible animals, reduce the infectiousness and shedding level, shorten the infectious period of infected animals, and/or curb the number of clinical cases), and evaluation of the potential impacts of imperfect Salmonella vaccines at the farm level is valuable to design effective intervention strategies. The objective of this study was to investigate the impact of imperfect Salmonella vaccines on the stochastic transmission dynamics in an adult dairy herd. To this end, we developed a semi-stochastic and individual-based continuous time Markov chain (CTMC) vaccination model with both direct and indirect transmission, and applied the CTMC vaccination model to Salmonella Cerro transmission in an adult dairy herd. Our results show that vaccines shortening the infectious period are most effective in reducing prevalence, and vaccines decreasing host susceptibility are most effective in reducing the outbreak size. Vaccines with multiple moderate efficacies may have the same effectiveness as vaccines with a single high efficacy in reducing prevalence, time to extinction, and outbreak size. Although the environment component has negligible contributions to the prevalence, time to extinction, and outbreak size for Salmonella Cerro in the herd, the relative importance of environment component was not assessed. This study indicates that an effective vaccination program against Salmonella Cerro

  1. Register-based predictors of violations of animal welfare legislation in dairy herds.

    PubMed

    Otten, N D; Nielsen, L R; Thomsen, P T; Houe, H

    2014-12-01

    The assessment of animal welfare can include resource-based or animal-based measures. Official animal welfare inspections in Denmark primarily control compliance with animal welfare legislation based on resource measures (e.g. housing system) and usually do not regard animal response parameters (e.g. clinical and behavioural observations). Herds selected for welfare inspections are sampled by a risk-based strategy based on existing register data. The aim of the present study was to evaluate register data variables as predictors of dairy herds with violations of the animal welfare legislation (VoAWL) defined as occurrence of at least one of the two most frequently violated measures found at recent inspections in Denmark, namely (a) presence of injured animals not separated from the rest of the group and/or (b) animals in a condition warranting euthanasia still being present in the herd. A total of 25 variables were extracted from the Danish Cattle Database and assessed as predictors using a multivariable logistic analysis of a data set including 73 Danish dairy herds, which all had more than 100 cows and cubicle loose-housing systems. Univariable screening was used to identify variables associated with VoAWL at a P-value<0.2 for the inclusion in a multivariable logistic regression analysis. Backward selection procedures identified the following variables for the final model predictive of VoAWL: increasing standard deviation of milk yield for first lactation cows, high bulk tank somatic cell count (⩾250 000 cells/ml) and suspiciously low number of recorded veterinary treatments (⩽25 treatments/100 cow years). The identified predictors may be explained by underlying management factors leading to impaired animal welfare in the herd, such as poor hygiene, feeding and management of dry or calving cows and sick animals. However, further investigations are required for causal inferences to be established.

  2. Concentration of anti-Müllerian hormone in dairy heifers is positively associated with productive herd life.

    PubMed

    Jimenez-Krassel, F; Scheetz, D M; Neuder, L M; Ireland, J L H; Pursley, J R; Smith, G W; Tempelman, R J; Ferris, T; Roudebush, W E; Mossa, F; Lonergan, P; Evans, A C O; Ireland, J J

    2015-05-01

    Reliable biomarkers predictive of productive herd life (time in herd after birth of first calf) have heretofore not been discovered in dairy cattle. However, circulating concentrations of anti-Müllerian hormone (AMH) are positively associated with number of follicles or antral follicle count (AFC), ovarian function, and fertility, and approximately 25% of cows have a relatively low AFC and low AMH concentrations. The present study tested the hypothesis that heifers with the lowest AMH concentrations have suboptimal fertility and are removed from a herd for poor reproductive performance at a greater rate, and therefore have a shorter productive herd life compared with age-matched herdmates with higher AMH. To test this hypothesis, 11- to 15-mo-old Holstein heifers (n=281) were subjected to a single measurement of AMH. All heifers not removed from the herd had the opportunity to complete 2 lactations and start their third lactation after calving. During this time, performance and health parameters for each individual were recorded daily by herd managers. Results showed that the quartile of heifers with the lowest AMH concentration also had, on average, a shorter productive herd life (by 196 d), a reduced survival rate after birth of the first calf, the lowest level of milk production (first lactation), the lowest total percentage of cows pregnant (across all lactations), the highest culling rates (first and second lactations and overall), and the highest culling rate for poor reproduction (first lactation) compared with age-matched herdmates with higher AMH. We concluded that a single determination of AMH concentration in young adult dairy heifers may be a simple diagnostic method to predict herd longevity, and AMH may be a useful phenotypic marker to improve longevity of dairy cows. PMID:25726106

  3. Lead arsenate poisoning in a herd of beef cattle.

    PubMed

    Stair, E L; Kirkpatrick, J G; Whitenack, D L

    1995-08-01

    Lead arsenate poisoning was diagnosed in 2 beef heifers and was suspected in 6 other cattle from the same herd that had died previously and were not examined. Clinical signs in affected cattle included staggering, dehydration, hemorrhage, acidemia, and shock. Diagnosis was by arsenic and lead analysis of urine samples and kidney and liver tissue digests. Both examined heifers died within 4 days of onset of clinical signs. These cattle had been moved from an area with poor grazing conditions to a pasture with abundant forage. This pasture had an open shed that contained an open sack of lead arsenate insecticide. Old stores of this inorganic insecticide may still exist on farms or ranches, and are a hazard to livestock.

  4. Evaluation of a protocol to reduce the incidence of neonatal calf diarrhoea on dairy herds.

    PubMed

    Meganck, V; Hoflack, G; Piepers, S; Opsomer, G

    2015-01-01

    Calf diarrhoea causes substantial economic losses in cattle herds worldwide. Neonatal calves are particularly sensitive to infections with enteropathogens. The present study focused on prevention against the main infectious causes of neonatal calf diarrhoea i.e. Escherichia coli, rota- and coronavirus, and Cryptosporidium parvum. Dairy herds (n=24) with a high percentage of neonatal calves scouring (>10%) were included and calves were sampled for the presence of these four enteropathogens. To decrease diarrhoea problems among neonatal calves, a standard protocol was tested on 13 herds (treatment group) where both C. parvum and either E. coli or rota- or coronavirus were identified as being involved, the other 11 herds served as control group. The protocol consisted of 2 points of action: preventive vaccination of dams against E. coli, rota- and coronavirus, and preventive administration of halofuginone lactate to newborn calves. The average percentage of calves suffering from neonatal diarrhoea (39.7% versus 14.3%, P<0.01) and the average percentage of faecal samples positive for C. parvum (34% versus 11%, P<0.05) differed significantly between control herds and treatment herds after implementation of the protocol. No significant differences between control and treatment group were observed in the percentage of calves excreting E. coli, rotavirus and coronavirus, both before and at the end of the trial. Furthermore, risk factors potentially associated with the development of neonatal calf scours were determined. Non-significant results were obtained for the effect of the protocol on duration of diarrhoea and the effect of the colostral IgG quantity on the risk of diarrhoea. Passive immunity transfer status of the calves, measured both before the onset and at the end of the study, were non-significant between groups. PMID:25475689

  5. Salmonella enterica Serotype Cerro Among Dairy Cattle in New York: An Emerging Pathogen?

    PubMed Central

    Warnick, Lorin D.; Elton, Mara; Rodriguez-Rivera, Lorraine D.; Siler, Julie D.; Wright, Emily M.; Gröhn, Yrjo T.; Wiedmann, Martin

    2010-01-01

    Abstract The focus of this study was Salmonella enterica serotype Cerro, a potentially emerging pathogen of cattle. Our objectives were to document the within-herd prevalence of Salmonella Cerro among a sample of New York dairy herds, to describe the antimicrobial resistance patterns and pulsed-field gel electrophoresis types of the isolates, and to elucidate the status of this serotype as a bovine pathogen. Data were collected prospectively from dairy herds throughout New York that had at least 150 lactating cows and that received clinical service from participating veterinarians. Following enrollment, Salmonella surveillance consisted of both environmental screening and disease monitoring within the herd. Herds positive by either environmental or fecal culture were sampled during three visits to estimate the within-herd prevalence of Salmonella. Among 57 enrolled herds, 44 (77%) yielded Salmonella-positive samples during the study period. Of these, 20 herds (46%) were positive for Salmonella Cerro. Upon follow-up sampling for estimation of prevalence, Cerro was identified in 10 of the 20 herds; the median within-herd Cerro prevalence was 17%, with a maximum of 53%. Antimicrobial resistance ranged from zero to nine drugs, and eight (40%) of the Cerro-positive farms generated drug-resistant isolates. Eight XbaI pulsed-field gel electrophoresis types were represented among 116 isolates tested, although 89% of these isolates shared the predominant type. Among herds with clinical cases, cattle that had signs consistent with salmonellosis were more likely to test positive for Cerro than apparently healthy cattle, as estimated by a logistic regression model that controlled for herd as a random effect (odds ratio: 3.9). There is little in the literature concerning Salmonella Cerro, and published reports suggest an absence of disease association in cattle. However, in our region there has been an apparent increase in the prevalence of this serotype among cattle with

  6. Technical indicators of financial performance in the dairy herd.

    PubMed

    Kristensen, E; Ostergaard, S; Krogh, M A; Enevoldsen, C

    2008-02-01

    Monte Carlo simulation was used to predict the long-term financial performance related to the technical performance of dairy herds. The indicators addressed were derived from data collected routinely in the herd. They indicated technical performance that can be affected by the farmer or the consultant, and they were derived from expected cause-effect relations between technical performance and financial performance at the herd level. The study included the indicators shape of lactation curve, reproduction efficiency, heifer management, variation between cows in lactation curve persistency, mortality in cows and calves, dynamics of body condition, and somatic cell counts. Each indicator was defined by 2 or 3 levels, and 2- and 3-factor interactions were included in the simulation experiment, which included 72 scenarios. Each scenario was replicated 200 times, and the resulting gross margin per cow was analyzed as the measure of financial performance. The potential effects of the selected indicators on the gross margin were estimated by means of an ANOVA. The final model allowed estimation of the financial value of specific changes within the key performance indicators. This study indicated that improving the shape of the herd-level lactation curve by 1 quartile was associated with an increase in gross margin of euro 227 per cow year. This represents 53% of the additional available gross margin associated with all the management changes included in the study. The improved herd-level lactation curve increased the gross margin 2.6 times more than improved reproduction efficiency, which again increased the gross margin 2.6 to 5.9 times more than improved management related to heifers, body condition score, mortality, and somatic cell counts. These results were implemented in a simple "metamodel" that used data extracted from ordinary management software to predict herd-specific financial performance related to major management changes. The metamodel was derived from

  7. Enterocytozoon bieneusi in Bovine Viral Diarrhea Virus (BVDV) infected and noninfected cattle herds.

    PubMed

    Juránková, J; Kamler, M; Kovařčík, K; Koudela, B

    2013-02-01

    Enterocytozoon bieneusi known as a causative agent of opportunistic infections instigating diarrhoea in AIDS patients was identified also in a number of immunocompetent patients and in a wide range of animals, including cattle. In the present study we tested if the Bovine Viral Diarrhea Virus (BVDV), the most common pathogen underlying immunosuppressive Bovine Viral Diarrhoea (BVD), can enhance the occurrence of opportunistic infections with E. bieneusi in cattle. Six dairy farms were investigated using ELISA to detect antibodies against or antigens arising from BVDV in collected sera. A total of 240 individual faecal samples from four age groups were examined for the presence of E. bieneusi by nested PCR. Sequence analysis of six E. bieneusi positive samples revealed the presence of the genotype I of E. bieneusi, previously described in cattle. The hypothesis expecting higher prevalence of E. bieneusi in BVDV positive cattle herds was not confirmed in this study; however this is the first description about E. bieneusi in cattle in the Czech Republic.

  8. Evaluation of BHV-1 antibody titer in a cattle herd against different BHV-1 strains.

    PubMed

    Lee, Megan; Reed, Aimee; Estill, Charles; Izume, Satoko; Dong, Jing; Jin, Ling

    2015-09-30

    Although modified-live multivalent vaccines, such as PregGuard GOLD and Bovi-Shield Gold, have been used routinely in both beef and dairy cattle in the US, abortion and respiratory diseases still occasionally occur following vaccination. To determine whether the antibody induced by the multivalent vaccine can recognize BHV-1 isolates from aborted animals, BHV-1 antibody titer was evaluated with two isolates from abortion cases and two vaccine BHV-1 viruses. Cattle serum was collected from a dairy herd that was vaccinated annually with Bovi-Shield Gold 5 vaccine. Among the 28 cattle tested, no statistical significant difference in serum neutralization titer was observed when test virus was either vaccine virus or clinical isolates. It suggests that the BHV-1 antibody from the vaccinated cattle can recognize both the vaccine virus and clinical isolates. However, it is noticed that cows at 5 years old or older had a significantly lower BHV-1 antibody titer on average than the average of SN titer in 3 year-old cows. Similarly, cows at 5 years or older had a significantly lower BVDV antibody titer than cows at about 2 years of age. In addition, cattle vaccinated within 0-2 months had a significantly higher BHV-1 titer than those that received vaccination 6 months or greater prior to titer measurement. In contrast, cattle that received a vaccination 6 months prior had a significantly higher anti-BVDV antibody titer than those vaccinated within 1-2 months. The BVDV antibody titers remained relatively unchanged between 6 months and 1 year post-vaccination. Our study suggests little antigenic variation exists between BHV-1 disease isolates and BHV-1 of the multivalent vaccines. In addition, BHV-1 antibody titer is relatively lower at 6 months post vaccination in those tested animals. However, the BVDV antibody titer remained relatively high after 6 months from time of vaccination.

  9. Short communication: Bulk milk somatic cell penalties in herds enrolled in Dairy Herd Improvement programs.

    PubMed

    Hand, K J; Godkin, M A; Kelton, D F

    2012-01-01

    The objective of this study was to determine the effect of somatic cell count (SCC) monitoring at the cow level through Dairy Herd Improvement (DHI) programs on the risk of bulk tank SCC (BTSCC) penalties. For the year 2009, BTSCC for all producers in Ontario were examined, for a total of 2,898 DHI herds, 1,186 non-DHI herds, and 48,250 BTSCC records. Two penalty levels were examined, where BTSCC exceeded 499,000 (P500) and 399,000 (P400) cells/mL. Data were modeled first to determine the odds of a BTSCC exceeding a set penalty threshold and second to determine the odds of incurring a penalty under the Ontario Milk Act. All data were modeled as a generalized mixed model with a binary link function. Random effects included herd, fixed effects included season of BTSCC (summer, May to September, and winter, October to April), total milk shipped per month (L), fat paid per month (kg), protein paid per month (kg), and participation or not in the DHI program. The likelihood of a BTSCC exceeding a penalty threshold in a non-DHI herd compared with a DHI herd was significantly greater than 1 at both penalty levels, where the odds ratios were estimated to be 1.42 [95% confidence interval (CI): 1.19 to 1.69] and 1.38 (95% CI: 1.25 to 1.54) for P500 and P400, respectively. The likelihood of incurring a BTSCC penalty (where 3 out of 4 consecutive BTSCC exceeded penalty thresholds) was not significantly different at P500; however, it was significantly different for P400, where the odds ratio was estimated to be 1.42 (95% CI: 1.12 to 1.81).

  10. Modelling the spread of bovine viral diarrhea virus (BVDV) in a beef cattle herd and its impact on herd productivity.

    PubMed

    Damman, Alix; Viet, Anne-France; Arnoux, Sandie; Guerrier-Chatellet, Marie-Claude; Petit, Etienne; Ezanno, Pauline

    2015-02-24

    Bovine viral diarrhea virus (BVDV) is a common pathogen of cattle herds that causes economic losses due to reproductive disorders in breeding cattle and increased morbidity and mortality amongst infected calves. Our objective was to evaluate the impact of BVDV spread on the productivity of a beef cow-calf herd using a stochastic model in discrete time that accounted for (1) the difference in transmission rates when animals are housed indoors versus grazing on pasture, (2) the external risk of disease introductions through fenceline contact with neighboring herds and the purchase of infected cattle, and (3) the risk of individual pregnant cattle generating persistently infected (PI) calves based on their stage in gestation. The model predicted the highest losses from BVDV during the first 3 years after disease was introduced into a naive herd. During the endemic phase, the impact of BVDV on the yearly herd productivity was much lower due to herd immunity. However, cumulative losses over 10 years in an endemic situation greatly surpassed the losses that occurred during the acute phase. A sensitivity analysis of key model parameters revealed that herd size, the duration of breeding, grazing, and selling periods, renewal rate of breeding females, and the level of numerical productivity expected by the farmer had a significant influence on the predicted losses. This model provides a valuable framework for evaluating the impact of BVDV and the efficacy of different control strategies in beef cow-calf herds.

  11. Seasonal influences on conception efficiency in Minnesota dairy herds.

    PubMed

    Udomprasert, P; Williamson, N B

    1987-09-01

    This study was undertaken to investigate the influence of climatological factors on the conception efficiency of cows in 23 Minnesota dairy herds between March 1982 and March 1985. It was found that year of insemination (P < 0.005), herd (P < 0.005), linear and quadratic terms of days open (P < 0.05), and linear and quadratic terms of minimum temperature (MNT), maximum temperature (MXT) and temperature humidity index (THI) were similarly related to observed monthly variations in first service conception rates. The year of insemination (P < 0.005), herd (P < 0.005), and linear and quadratic terms of MNT, MXT and THI were also related to the variation in overall conception rate. Conception rate declined from April to August and increased from August to January. There was an 11% difference between the month of lowest fertility (August) and the month of highest fertility (November). It can be concluded that climatological factors appear to depress herd fertility in the northern United States as well as in the warmer southern areas. Thus, consideration should be given to strategies which will minimize the impact of the observed fertility depression due to these climatic factors.

  12. Linear Classification of Dairy Cattle. Slide Script.

    ERIC Educational Resources Information Center

    Sipiorski, James; Spike, Peter

    This slide script, part of a series of slide scripts designed for use in vocational agriculture classes, deals with principles of the linear classification of dairy cattle. Included in the guide are narrations for use with 63 slides, which illustrate the following areas that are considered in the linear classification system: stature, strength,…

  13. Management practices as risk factors for the presence of bulk milk antibodies to Salmonella, Neospora caninum and Leptospira interrogans serovar hardjo in Irish dairy herds.

    PubMed

    O' Doherty, E; Berry, D P; O' Grady, L; Sayers, R

    2014-06-01

    A survey of management practices in 309 Irish dairy herds was used to identify risk factors for the presence of antibodies to Salmonella, Neospora caninum and Leptospira interrogans serovar hardjo in extensively managed unvaccinated dairy herds. A previous study documented a herd-level seroprevalence in bulk milk of 49%, 19% and 86% for Salmonella, Neospora caninum and leptospira interrogans serovar hardjo, respectively in the unvaccinated proportion of these 309 herds in 2009. Association analyses in the present study were carried out using multiple logistic regression models. Herds where cattle were purchased or introduced had a greater likelihood of being positive to leptospira interrogans serovar hardjo (P<0.01) and Salmonella (P<0.01). Larger herds had a greater likelihood of recording a positive bulk milk antibody result to leptospira interrogans serovar hardjo (P<0.05). Herds that practiced year round calving were more likely to be positive to Neospora caninum (P<0.05) compared to herds with a spring-calving season, with no difference in risk between herds that practiced split calving compared to herds that practiced spring calving. No association was found between presence of dogs on farms and prevalence of Neospora caninum possibly due to limited access of dogs to infected materials including afterbirths. The information from this study will assist in the design of suitable control programmes for the diseases under investigation in pasture-based livestock systems. PMID:24661904

  14. Prevalence in bulk tank milk and epidemiology of Campylobacter jejuni in dairy herds in Northern Italy.

    PubMed

    Bianchini, Valentina; Borella, Laura; Benedetti, Valentina; Parisi, Antonio; Miccolupo, Angela; Santoro, Eliana; Recordati, Camilla; Luini, Mario

    2014-03-01

    Thermotolerant Campylobacter spp. are frequently the cause of human gastroenteritis and have assumed more importance in Italy following the increased consumption of raw milk. Our objectives were to determine the prevalence and genotypes of Campylobacter spp. in dairy herds and to investigate the possible sources of bulk milk contamination. Bulk milk from dairy herds (n = 282) was cultured for Campylobacter spp. and Enterobacteriaceae. At three Campylobacter jejuni-positive farms, bovine feces, pigeon intestines, milk, and water points were also investigated. Isolates were identified by PCR and genotyped using multilocus sequence typing (MLST). C. jejuni was detected in 34 (12%) bulk milk samples. The strains belonged to 14 sequence types, and the most common clonal complexes were CC-21, CC-48, and CC-403. No association was demonstrated between the presence of C. jejuni and high levels of Enterobacteriaceae in bulk milk. At the three farms examined, C. jejuni was isolated from bovine feces (25/82 [30.5%]), pigeon intestines (13/60 [21.7%]), bulk milk (10/24 [41.7%]), and water points (4/16 [25%]). MLST revealed lineages that were common between milk and bovine feces but distinct between cattle and pigeons. In one herd, C. jejuni with the same genotype was isolated repeatedly from bulk milk and a cow with an udder infection. Our results showed a high prevalence of C. jejuni in bulk milk and suggested that udder excretion, in addition to fecal matter, may be a route of bulk milk contamination. MLST analysis indicated that pigeons are probably not relevant for the transmission of C. jejuni to cattle and for milk contamination.

  15. Prevalence in Bulk Tank Milk and Epidemiology of Campylobacter jejuni in Dairy Herds in Northern Italy

    PubMed Central

    Bianchini, Valentina; Borella, Laura; Benedetti, Valentina; Parisi, Antonio; Miccolupo, Angela; Santoro, Eliana; Recordati, Camilla

    2014-01-01

    Thermotolerant Campylobacter spp. are frequently the cause of human gastroenteritis and have assumed more importance in Italy following the increased consumption of raw milk. Our objectives were to determine the prevalence and genotypes of Campylobacter spp. in dairy herds and to investigate the possible sources of bulk milk contamination. Bulk milk from dairy herds (n = 282) was cultured for Campylobacter spp. and Enterobacteriaceae. At three Campylobacter jejuni-positive farms, bovine feces, pigeon intestines, milk, and water points were also investigated. Isolates were identified by PCR and genotyped using multilocus sequence typing (MLST). C. jejuni was detected in 34 (12%) bulk milk samples. The strains belonged to 14 sequence types, and the most common clonal complexes were CC-21, CC-48, and CC-403. No association was demonstrated between the presence of C. jejuni and high levels of Enterobacteriaceae in bulk milk. At the three farms examined, C. jejuni was isolated from bovine feces (25/82 [30.5%]), pigeon intestines (13/60 [21.7%]), bulk milk (10/24 [41.7%]), and water points (4/16 [25%]). MLST revealed lineages that were common between milk and bovine feces but distinct between cattle and pigeons. In one herd, C. jejuni with the same genotype was isolated repeatedly from bulk milk and a cow with an udder infection. Our results showed a high prevalence of C. jejuni in bulk milk and suggested that udder excretion, in addition to fecal matter, may be a route of bulk milk contamination. MLST analysis indicated that pigeons are probably not relevant for the transmission of C. jejuni to cattle and for milk contamination. PMID:24413598

  16. Introduction to Dairy Production. Instructor Guide [and] Student Reference.

    ERIC Educational Resources Information Center

    Duncan, Kevin

    This packet contains an instructor guide and student reference for a course in introduction to dairy production. The curriculum contains the following six lessons: (1) introduction to the dairy industry; (2) breeds of dairy cattle; (3) principles of dairy cattle selection; (4) herd management; (5) herd health; and (6) industry issues. The…

  17. Calculation and delivery of US genomic evaluations for dairy cattle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In April 2013, the responsibility for calculation and distribution of genomic evaluations for dairy cattle was transferred from the USDA to the US dairy industry’s Council on Dairy Cattle Breeding; the responsibility for development of evaluation methodology remained with the USDA. The Council on Da...

  18. Association between antibody status to bovine herpesvirus 1 and quality of milk in dairy herds in Poland.

    PubMed

    Rola, J G; Larska, M; Grzeszuk, M; Rola, J

    2015-02-01

    Bovine herpesvirus 1 (BoHV1) is one of the most important pathogens of cattle; however, its effect on somatic cell count and milk components is not completely understood. The aim of the current study was to examine the effect of BoHV1 infection on quality of bovine bulk tank milk (BTM). A total of 1,790 individual blood samples collected at 28 dairy farms were used to determine the BoHV1 infection status of the herds with ELISA tests. The quality parameters of milk were evaluated by instrumental methods with BTM samples collected at monthly intervals from May 2011 to May 2012. The statistical analysis was performed to study the associations between BoHV1 herd status, quality of BTM, and herd-specific parameters. The risk factors influencing bulk milk somatic cell count (BMSCC) were estimated using the multivariable mixed-effects maximum likelihood regression model. The true prevalences of BoHV1 infection at the animal and herd levels were 49.3 and 64.6%, respectively. The average BMSCC differed significantly between the herds grouped accordingly to their BoHV1 infection status. Interestingly, the highest BMSCC was observed in the vaccinated herds (240.3×10(3) cells/mL). Additionally, the BoHV1 herd status had a significant effect on the fat content of BTM. The largest herds that were investigated had a BoHV1 seroprevalence over 30%. The herd status was considerably influenced by the numbers of cows in the herds. Besides, no significant differences in total bacterial count or protein content in milk from BoHV1-infected und uninfected herds were observed. An increase in BMSCC was observed during summer compared with the winter months regardless of the BoHV1 status of the herds. In the final multivariable regression model, the main risk factors associated with BMSCC were BoHV1 herd status, the percentage of BoHV1 infected animals in a herd, the number of cows in a herd, and the season. Our study suggests that BoHV1 infection may influence BMSCC levels, which are key

  19. A review of current timed-AI (TAI) programs for beef and dairy cattle.

    PubMed

    Colazo, Marcos G; Mapletoft, Reuben J

    2014-08-01

    This is a review of the physiology and endocrinology of the estrous cycle and how ovarian physiology can be manipulated and controlled for timed artificial insemination (TAI) in beef and dairy cattle. Estrus detection is required for artificial insemination (AI), but it is done poorly in dairy cattle and it is difficult in beef cattle. Protocols that synchronize follicle growth, corpus luteum regression and ovulation, allowing for TAI, result in improved reproductive performance, because all animals are inseminated whether they show estrus or not. As result, TAI programs have become an integral part of reproductive management in many dairy herds and offer beef producers the opportunity to incorporate AI into their herds. Gonadotropin-releasing hormone-based protocols are commonly used in North America for estrus synchronization as part of a TAI program. Protocols that increase pregnancy rates in lactating dairy cows and suckling beef cows have been developed. Protocols that improve pregnancy rates in heifers, acyclic beef cows, and resynchronized lactating dairy cows are also discussed.

  20. A review of current timed-AI (TAI) programs for beef and dairy cattle.

    PubMed

    Colazo, Marcos G; Mapletoft, Reuben J

    2014-08-01

    This is a review of the physiology and endocrinology of the estrous cycle and how ovarian physiology can be manipulated and controlled for timed artificial insemination (TAI) in beef and dairy cattle. Estrus detection is required for artificial insemination (AI), but it is done poorly in dairy cattle and it is difficult in beef cattle. Protocols that synchronize follicle growth, corpus luteum regression and ovulation, allowing for TAI, result in improved reproductive performance, because all animals are inseminated whether they show estrus or not. As result, TAI programs have become an integral part of reproductive management in many dairy herds and offer beef producers the opportunity to incorporate AI into their herds. Gonadotropin-releasing hormone-based protocols are commonly used in North America for estrus synchronization as part of a TAI program. Protocols that increase pregnancy rates in lactating dairy cows and suckling beef cows have been developed. Protocols that improve pregnancy rates in heifers, acyclic beef cows, and resynchronized lactating dairy cows are also discussed. PMID:25082993

  1. Lead excretion in milk of accidentally exposed dairy cattle.

    PubMed

    Bischoff, Karyn; Higgins, William; Thompson, Belinda; Ebel, Joseph G

    2014-01-01

    Lead (Pb) exposure in dairy cattle is associated with economic losses due to mortality and treatment costs, but with production animals there is also risk to the human food chain. The first objective of this study was to quantify the Pb concentration in milk from Pb-exposed cattle. The second objective was to correlate blood and milk Pb concentrations from individual cows. The third objective was long-term monitoring to determine the duration of milk contamination after exposure ceased. A dairy herd of more than 100 cows was accidentally exposed to Pb-contaminated feed. Milk and blood were collected for Pb analysis. Serial collection of milk samples continued for 2.5 years. The initial concentration of Pb in bulk tank milk was 0.0999 mg l⁻¹. The highest milk Pb concentration from an individual cow was 0.4657 mg l⁻¹ and the highest blood Pb concentration was 1.216 mg l⁻¹. One milk sample collected at the end of the study (day 922) contained 0.0117 mg Pb l⁻¹ of Pb. The calculated relationship between milk (y) and blood (x) Pb concentration was ln(y) = 3.4(x) - 2.21 (R² = 0.98).

  2. The Effect of Clinical Outbreaks of Salmonellosis on the Prevalence of Fecal Salmonella Shedding Among Dairy Cattle in New York

    PubMed Central

    Warnick, Lorin D.; Elton, Mara; Gröhn, Yrjo T.; McDonough, Patrick L.; Siler, Julie D.

    2010-01-01

    Abstract The objective of this study was to determine if the within-herd prevalence of fecal Salmonella shedding is higher in dairy herds with clinical outbreaks of disease, as compared to herds with subclinical infections only. Data were collected prospectively from dairy herds throughout New York that had at least 150 lactating cows and that received clinical service from participating veterinarians. After enrollment, Salmonella surveillance consisted of both environmental screening and disease monitoring within the herd. Herds positive by either environmental or fecal culture were sampled during three visits to estimate the within-herd prevalence of Salmonella. We characterized isolates by serovar and antimicrobial resistance pattern. Among 57 enrolled herds, 44 (77%) yielded Salmonella-positive samples during the study period; 27 (61%) of the positive herds had Salmonella isolated from environmental samples only, and 17 (39%) had one or more laboratory-confirmed clinical cases. The within-herd prevalence of fecal Salmonella shedding ranged from 0 to 53%. Salmonella Cerro was the predominant serovar, accounting for 56% of all isolates. Antimicrobial resistance ranged from zero to nine drugs, and 14 (32%) of the positive farms generated multidrug-resistant isolates. Herds with laboratory-confirmed clinical cases had a higher prevalence of fecal Salmonella shedding than herds that only generated positive environmental samples, as estimated by a Poisson regression model (prevalence ratio, 2.7; p = 0.01). An association between dairy herd outbreaks of salmonellosis and a higher prevalence of asymptomatic shedding should help guide strategies for reducing the public health threat of Salmonella, as the ability to recognize high-risk herds by clinical laboratory submissions presents an obvious opportunity to maximize food safety at the preharvest level. This is in contrast with other foodborne zoonotic pathogens, such as Campylobacter jejuni and Escherichia coli O

  3. The effect of clinical outbreaks of salmonellosis on the prevalence of fecal Salmonella shedding among dairy cattle in New York.

    PubMed

    Cummings, Kevin J; Warnick, Lorin D; Elton, Mara; Gröhn, Yrjo T; McDonough, Patrick L; Siler, Julie D

    2010-07-01

    The objective of this study was to determine if the within-herd prevalence of fecal Salmonella shedding is higher in dairy herds with clinical outbreaks of disease, as compared to herds with subclinical infections only. Data were collected prospectively from dairy herds throughout New York that had at least 150 lactating cows and that received clinical service from participating veterinarians. After enrollment, Salmonella surveillance consisted of both environmental screening and disease monitoring within the herd. Herds positive by either environmental or fecal culture were sampled during three visits to estimate the within-herd prevalence of Salmonella. We characterized isolates by serovar and antimicrobial resistance pattern. Among 57 enrolled herds, 44 (77%) yielded Salmonella-positive samples during the study period; 27 (61%) of the positive herds had Salmonella isolated from environmental samples only, and 17 (39%) had one or more laboratory-confirmed clinical cases. The within-herd prevalence of fecal Salmonella shedding ranged from 0 to 53%. Salmonella Cerro was the predominant serovar, accounting for 56% of all isolates. Antimicrobial resistance ranged from zero to nine drugs, and 14 (32%) of the positive farms generated multidrug-resistant isolates. Herds with laboratory-confirmed clinical cases had a higher prevalence of fecal Salmonella shedding than herds that only generated positive environmental samples, as estimated by a Poisson regression model (prevalence ratio, 2.7; p = 0.01). An association between dairy herd outbreaks of salmonellosis and a higher prevalence of asymptomatic shedding should help guide strategies for reducing the public health threat of Salmonella, as the ability to recognize high-risk herds by clinical laboratory submissions presents an obvious opportunity to maximize food safety at the preharvest level. This is in contrast with other foodborne zoonotic pathogens, such as Campylobacter jejuni and Escherichia coli O157:H7, which

  4. Effects of infectious young stock on results of certification, surveillance and control programmes for paratuberculosis in dairy herds.

    PubMed

    Weber, M F; Groenendaal, H

    2012-01-27

    In many epidemiological models for paratuberculosis, it is assumed that infected young stock (<2 years of age) do not shed Mycobacterium avium subsp. paratuberculosis (MAP) before adulthood. If this assumption were true, the effective separation of young stock from adult cattle (≥ 2 years) would largely prevent postnatal infections, provided that uninfected adult cattle are highly resistant to infection. However, this assumption is in contrast with observed faecal shedding of MAP in young stock. Consequently, this assumption may have resulted in an underestimation of the effects of MAP transmission in herds participating in certification-, surveillance-, and control programmes for paratuberculosis. Therefore, the aim of the present study was to evaluate the long-term effects of transmission of MAP amongst young stock on key output parameters of certification-, surveillance-, and control programmes for paratuberculosis in simulated closed dairy herds. Closed Dutch dairy herds participating in a paratuberculosis programme were simulated with a stochastic model, JohneSSim. Various test schemes, preventive management measures, distributions of age at onset of faecal shedding and rates of effective contacts between young stock were simulated. The results indicate that transmission of MAP amongst young stock has no relevant effects on the animal-level prevalence and milk quality of herds that are certified in a paratuberculosis programme. However, transmission of MAP amongst young stock increased the economic losses due to paratuberculosis and costs of participation in a programme. Moreover, it substantially decreased the beneficial effect of the separation of young stock from adult cattle on the probability of being certified. However, even in the presence of transmission of MAP amongst young stock, preventive management measures to separate young stock from adult cattle remain important.

  5. Triennial Lactation Symposium: Opportunities for improving milk production efficiency in dairy cattle.

    PubMed

    Connor, E E; Hutchison, J L; Olson, K M; Norman, H D

    2012-05-01

    Increasing feed costs and the desire to improve environmental stewardship have stimulated renewed interest in improving feed efficiency of livestock, including that of US dairy herds. For instance, USDA cost projections for corn and soybean meal suggest a 20% increase over 2010 pricing for a 16% protein mixed dairy cow ration in 2011, which may lead to a reduction in cow numbers to maintain profitability of dairy production. Furthermore, an October 2010 study by The Innovation Center for US Dairy to assess the carbon footprint of fluid milk found that the efficiency of feed conversion is the single greatest factor contributing to variation in the carbon footprint because of its effects on methane release during enteric fermentation and from manure. Thus, we are conducting research in contemporary US Holsteins to identify cows most efficient at converting feed to milk in temperate climates using residual feed intake (RFI), a measure used successfully to identify the beef cattle most efficient at converting feed to gain. Residual feed intake is calculated as the difference between predicted and actual feed intake to support maintenance and production (e.g., growth in beef cattle, or milk in dairy cattle). Heritability estimates for RFI in dairy cattle reported in the literature range from 0.01 to 0.38. Selection for a decreased RFI phenotype can reduce feed intake, methane production, nutrient losses in manure, and visceral organ weights substantially in beef cattle. We have estimated RFI during early lactation (i.e., to 90 d in milk) in the Beltsville Agricultural Research Center Holstein herd and observed a mean difference of 3.7 kg/d (P < 0.0001) in actual DMI between the efficient and inefficient groups (±0.5 SD from the mean RFI of 0), with no evidence of differences (P > 0.20) in mean BW, ADG, or energy-corrected milk exhibited between the 2 groups. These results indicate promise for using RFI in dairy cattle to improve feed conversion to milk. Previous and

  6. Invited review: overview of new traits and phenotyping strategies in dairy cattle with a focus on functional traits

    Technology Transfer Automated Retrieval System (TEKTRAN)

    For several decades, breeding goals in dairy cattle focused on increased milk production. However, many functional traits have negative genetic correlations with milk yield and reductions in genetic merit for health and fitness have been observed. Herd management has been challenged to compensate fo...

  7. [Control measures in officially acknowledged brucellosis-free and leukosis unsuspected dairy herds on the basis of bulk milk samples in combination with ELISA tests].

    PubMed

    Forschner, E; Bünger, I; Krause, H P; Küttler, D

    1989-01-01

    1. EC- and National Regulations. Since 1988 the EC-regulations accept in addition to the on Agar Gel Immunodiffusion test (AGIDT) based blood serum testing of cattle herds that are filed as "free from Enzootic Bovine Leucosis" the use of ELISA for this purpose. The regular testings in dairy cattle herds can be done alternatively with single or pooled milk samples, in other herds with pooled blood sera using ELISA. General condition is only a minimal sensitivity of the test to detect the European EBL Antibody Standard ("E4") in a dilution of 1:10 in negative serum or 1:250 in negative milk. Adequate national regulations are in preparation. The present limitation of pool sizes, blood maximum 50 animals without preparation steps 20, and milk after concentration treatment 50 cows is neutralized by proceedings in development of higher sensitive ELISA tests. This limitation should be canceled. Herd bulk milk samples without size limitations are accepted to be tested with "Milk Ring Test" by EC for the regular testings in filed "Brucellosis Free Dairy Cattle Herds". The alternative use of more sensitive (and more specific) ELISA tests for this purpose including the technical conditions is in a final discussion. 2. Scientific-Technical Base for Using the Chances of the Proceeding in the EC-Regulations. The realisation of the EC accepted or final discussed ELISA based bulk milk testing to control filed "EBL- and/or Brucellosis Free Herds" depends on some basic conditions like sensitivity, specificity, and variability of the ELISA systems. Field trials of more than 20,000 bulk milk samples in case of Brucellosis and more than 2,000 in case of EBL show the feasibilities and the limits of the ELISA systems in defining the status of the herds. The Brucellosis respectively the EBL situations of the dairy cattle herds tested in this trail were well known by history and by investigation of single animal blood samples using conventional tests. Special test run variations of

  8. Mass vaccination and herd immunity: cattle and buffalo.

    PubMed

    Roeder, P L; Taylor, W P

    2007-04-01

    The design of effective programmes for emergency response to incursion of epizootic diseases of cattle, for exclusion of such diseases and for implementation of progressive control in enzootic situations leading to eventual virus elimination, is currently largely empirical. This needs to be remedied to provide more cost-effective use of vaccines and more effective control. At population level, protective effects of immunisation can extend well beyond the individual, influencing the dynamics of viral propagation within the whole population, non-vaccinated as well as vaccinated. This concept of herd immunity and application of the resulting epidemiological principles, combined with experience gained from disease control programmes such as the Global Rinderpest Eradication Programme has much to offer in designing effective science-based control programmes. This paper explores practical exploitation of the herd immunity principle by considering some of the factors which militate against mass vaccination achieving effective levels of herd immunity and, with these in mind, suggesting ways to optimise the efficiency of mass vaccination programmes.

  9. Survey of infectious etiologies of bovine abortion during mid- to late gestation in dairy herds.

    PubMed

    Barkallah, Mohamed; Gharbi, Yaakoub; Hassena, Amal Ben; Slima, Ahlem Ben; Mallek, Zouhir; Gautier, Michel; Greub, Gilbert; Gdoura, Radhouane; Fendri, Imen

    2014-01-01

    Bovine abortion of unknown infectious etiology still remains a major economic problem. Thus, we investigated whether Brucella spp., Listeria monocytogenes, Salmonella spp., Campylobacter spp. and Coxiella burnetii are associated with abortion and/or stillbirth in Tunisian dairy cattle. Using a pan-Chlamydiales PCR, we also investigated the role of Chlamydiaceae, Waddlia chondrophila, Parachlamydia acanthamoebae and other members of the Chlamydiales order in this setting. Veterinary samples taken from mid to late-term abortions from twenty dairy herds were tested. From a total of 150 abortion cases collected, infectious agents were detected by PCR in 73 (48.66%) cases, 13 (8.66%) of which represented co-infections with two infectious agents. Detected pathogens include Brucella spp (31.3%), Chlamydiaceae (4.66%), Waddlia chondrophila (8%), Parachlamydia acanthamoebae (5.33%), Listeria monocytogenes (4.66%) and Salmonella spp. (3.33%). In contrast, Campylobacter spp. and Coxiella burnetii DNA were not detected among the investigated veterinary samples. This demonstrates that different bacterial agents may cause bovine abortion in Tunisia. This is the first report suggesting the role of Parachlamydia acanthamoebae in bovine abortion in Africa. Further studies with a larger number of samples are necessary to confirm whether this emerging pathogen is directly linked to abortion in cattle.

  10. Survey of Infectious Etiologies of Bovine Abortion during Mid- to Late Gestation in Dairy Herds

    PubMed Central

    Barkallah, Mohamed; Slima, Ahlem Ben; Mallek, Zouhir; Gautier, Michel; Greub, Gilbert; Gdoura, Radhouane; Fendri, Imen

    2014-01-01

    Bovine abortion of unknown infectious etiology still remains a major economic problem. Thus, we investigated whether Brucella spp., Listeria monocytogenes, Salmonella spp., Campylobacter spp. and Coxiella burnetii are associated with abortion and/or stillbirth in Tunisian dairy cattle. Using a pan-Chlamydiales PCR, we also investigated the role of Chlamydiaceae, Waddlia chondrophila, Parachlamydia acanthamoebae and other members of the Chlamydiales order in this setting. Veterinary samples taken from mid to late-term abortions from twenty dairy herds were tested. From a total of 150 abortion cases collected, infectious agents were detected by PCR in 73 (48.66%) cases, 13 (8.66%) of which represented co-infections with two infectious agents. Detected pathogens include Brucella spp (31.3%), Chlamydiaceae (4.66%), Waddlia chondrophila (8%), Parachlamydia acanthamoebae (5.33%), Listeria monocytogenes (4.66%) and Salmonella spp. (3.33%). In contrast, Campylobacter spp. and Coxiella burnetii DNA were not detected among the investigated veterinary samples. This demonstrates that different bacterial agents may cause bovine abortion in Tunisia. This is the first report suggesting the role of Parachlamydia acanthamoebae in bovine abortion in Africa. Further studies with a larger number of samples are necessary to confirm whether this emerging pathogen is directly linked to abortion in cattle. PMID:24662769

  11. Prevalence of Giardia duodenalis assemblages among dairy herds in the New York City Watershed.

    PubMed

    Mark-Carew, Miguella P; Wade, Susan E; Chang, Yung-Fu; Schaaf, Stephanie; Mohammed, Hussni O

    2012-04-30

    A longitudinal herd-level study was carried out to determine the cumulative incidence of Giardia duodenalis infections in dairy cattle in the New York City Watershed. We also sought to assess the changes in infection pattern of animals diagnosed as shedding Giardia over time, determine risk factors that may be associated with G. duodenalis infections, and identify potentially zoonotic infections. A total of 2109 fecal samples were randomly collected from dairy cattle at 34 farms in the New York City Watershed on a seasonal basis. A total of 504 Giardia-positive samples were identified by zinc sulfate flotation. The overall cumulative incidence of G. duodenalis based on flotation results was 23.9% with 73.8% of all infections occurring in animals under 180 days of age (372/504). The intensity of infection ranged from 2 to 563,200 cysts/gram of feces. Cattle shedding Cryptosporidium spp. oocysts were twice as likely to shed G. duodenalis cysts in comparison to the animals that did not shed oocysts (1.81 95% CI 1.26-2.60 p=0.0012). In the multivariate analysis, only the age of the animal and the presence of dogs on the farm were significantly associated with the likelihood of shedding G. duodenalis. DNA was extracted from positive samples and analyzed by polymerase chain reaction (PCR) of the beta-giardin and triosephosphate isomerase genes of Giardia spp. 304 samples were analyzed by PCR of which 131 were sequenced. 22.1% of sequenced samples were identified as assemblage A and 77.9% were identified as assemblage E. Interestingly, 100% of specimens identified as assemblage A were from calves under 84 days of age indicating that younger cattle are important reservoirs for potentially zoonotic assemblages of G. duodenalis.

  12. Weather and soil type affect incidence of fasciolosis in dairy cow herds.

    PubMed

    Selemetas, N; Phelan, P; O'Kiely, P; Waal, T de

    2014-10-18

    Fasciolosis caused by Fasciola hepatica is generally a subclinical infection of dairy cows and can result in marked economic losses on Irish dairy farms. This study investigated the exposure to F hepatica in 237 dairy cow herds, using an in-house antibody-detection ELISA applied to bulk tank milk (BTM) samples collected in the autumn of 2012. A total of 364 BTM samples were collected from 237 different herds, with 127 farmers submitting BTM samples in two consecutive months. Analysis of the BTM samples indicated that 67 per cent (n= 159) of the dairy herds had been exposed to F hepatica. Rainfall, temperature and soil types were significantly different between the exposed and non-exposed herds (P<0.05), highlighting the role of these variables to the exposure to F hepatica. Among the 127 herds that provided two monthly milk samples, 83 herds were exposed to F hepatica and 82 increased their F hepatica antibody levels at the later sampling time (P<0.01).The findings of this study confirm the high prevalence of F hepatica antibodies in Irish dairy herds and show the rise in antibody levels during autumn. This study is the first step towards assessing the spatiotemporal pattern of fasciolosis in dairy herds in Ireland.

  13. Herd-level risk factors for bovine viral diarrhea virus infection in dairy herds from Southern Brazil.

    PubMed

    Almeida, L L; Miranda, I C S; Hein, H E; Neto, W Santiago; Costa, E F; Marks, F S; Rodenbusch, C R; Canal, C W; Corbellini, L G

    2013-12-01

    A cross-sectional study was carried out to identify risk factors for bovine viral diarrhea virus (BVDV) infection in 300 randomly selected dairy herds which were tested for antibodies in bulk tank milk (BTM) using a commercial indirect ELISA kit (SVANOVA). Results from the analysis were interpreted according to the Swedish BVDV control scheme. The testing revealed 129 (43%) BTM BVDV antibody-positive herds. Use of artificial insemination (AI) and herd size were significantly associated with BVDV serological status (P<0.05). Dairy herds that use AI had 2.82 increased odds of BVDV-seropositivity (95% CI: 1.02-7.24). Since the semen used in the studied population come from known selected sires, it was hypothesized that AI technicians should represent an important risk factor because the increasing number of visitors in the farm can introduce the virus through the clothes, shoes and contaminated equipment.

  14. Designing a risk-based surveillance program for Mycobacterium avium ssp. paratuberculosis in Norwegian dairy herds using multivariate statistical process control analysis.

    PubMed

    Whist, A C; Liland, K H; Jonsson, M E; Sæbø, S; Sviland, S; Østerås, O; Norström, M; Hopp, P

    2014-11-01

    Surveillance programs for animal diseases are critical to early disease detection and risk estimation and to documenting a population's disease status at a given time. The aim of this study was to describe a risk-based surveillance program for detecting Mycobacterium avium ssp. paratuberculosis (MAP) infection in Norwegian dairy cattle. The included risk factors for detecting MAP were purchase of cattle, combined cattle and goat farming, and location of the cattle farm in counties containing goats with MAP. The risk indicators included production data [culling of animals >3 yr of age, carcass conformation of animals >3 yr of age, milk production decrease in older lactating cows (lactations 3, 4, and 5)], and clinical data (diarrhea, enteritis, or both, in animals >3 yr of age). Except for combined cattle and goat farming and cattle farm location, all data were collected at the cow level and summarized at the herd level. Predefined risk factors and risk indicators were extracted from different national databases and combined in a multivariate statistical process control to obtain a risk assessment for each herd. The ordinary Hotelling's T(2) statistic was applied as a multivariate, standardized measure of difference between the current observed state and the average state of the risk factors for a given herd. To make the analysis more robust and adapt it to the slowly developing nature of MAP, monthly risk calculations were based on data accumulated during a 24-mo period. Monitoring of these variables was performed to identify outliers that may indicate deviance in one or more of the underlying processes. The highest-ranked herds were scattered all over Norway and clustered in high-density dairy cattle farm areas. The resulting rankings of herds are being used in the national surveillance program for MAP in 2014 to increase the sensitivity of the ongoing surveillance program in which 5 fecal samples for bacteriological examination are collected from 25 dairy herds

  15. An investigation of risk factors for nocardial mastitis in central Alberta dairy herds

    PubMed Central

    Ollis, Gerald W.; Schoonderwoerd, Matthew; Schipper, Casey

    1991-01-01

    A case-control study was undertaken during the summer of 1989 in central Alberta dairy herds to identify independent predictors of nocardial mastitis. Thirty-seven herds with nocardial mastitis were matched with control herds based on herd size, milk production, and enrolment in Alberta Dairy Herd Improvement Services. Control herds were considered free of nocardial mastitis based on negative cultures of four weekly bulk tank milk samples and one composite milk sample collected during the same period from each lactating cow in the herd. A detailed questionnaire on herd management was completed during farm visits. The use of blanket dry cow therapy was not found to be a risk factor for nocardial mastitis. Dry cow therapy with intramammary products containing neomycin and the use of multidose vials of dry cow medications were the only predisposing factors identified as being significantly associated with nocardial mastitis in central Alberta dairy herds. Use of neomycin as a dry cow therapy increased the odds of nocardial mastitis occurring in these dairy herds by 169 times. PMID:17423768

  16. Vitamin D status of dairy cattle: Outcomes of current practices in the dairy industry

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The need for vitamin D supplementation of dairy cattle has been known for the better part of the last century and is well-appreciated by dairy producers and nutritionists. Whether current recommendations and practices for supplemental vitamin D are meeting the needs of dairy cattle, however, is not...

  17. Risk factors for displaced abomasum or ketosis in Swedish dairy herds.

    PubMed

    Stengärde, L; Hultgren, J; Tråvén, M; Holtenius, K; Emanuelson, U

    2012-03-01

    Risk factors associated with high or low long-term incidence of displaced abomasum (DA) or clinical ketosis were studied in 60 Swedish dairy herds, using multivariable logistic regression modelling. Forty high-incidence herds were included as cases and 20 low-incidence herds as controls. Incidence rates were calculated based on veterinary records of clinical diagnoses. During the 3-year period preceding the herd classification, herds with a high incidence had a disease incidence of DA or clinical ketosis above the 3rd quartile in a national database for disease recordings. Control herds had no cows with DA or clinical ketosis. All herds were visited during the housing period and herdsmen were interviewed about management routines, housing, feeding, milk yield, and herd health. Target groups were heifers in late gestation, dry cows, and cows in early lactation. Univariable logistic regression was used to screen for factors associated with being a high-incidence herd. A multivariable logistic regression model was built using stepwise regression. A higher maximum daily milk yield in multiparous cows and a large herd size (p=0.054 and p=0.066, respectively) tended to be associated with being a high-incidence herd. Not cleaning the heifer feeding platform daily increased the odds of having a high-incidence herd twelvefold (p<0.01). Keeping cows in only one group in the dry period increased the odds of having a high incidence herd eightfold (p=0.03). Herd size was confounded with housing system. Housing system was therefore added to the final logistic regression model. In conclusion, a large herd size, a high maximum daily milk yield, keeping dry cows in one group, and not cleaning the feeding platform daily appear to be important risk factors for a high incidence of DA or clinical ketosis in Swedish dairy herds. These results confirm the importance of housing, management and feeding in the prevention of metabolic disorders in dairy cows around parturition and in early

  18. Embryo development in dairy cattle.

    PubMed

    Lonergan, Pat; Fair, Trudee; Forde, Niamh; Rizos, Dimitrios

    2016-07-01

    During the past 50 years, the fertility of high-producing lactating dairy cows has decreased, associated with intensive selection for increased milk production. The physiological and metabolic changes associated with high milk production, including decreased (glucose, insulin, IGF-I) or increased (nonesterified fatty acids, ketone bodies) concentrations of circulating metabolites during nutrient partitioning associated with negative energy balance as well as uterine and nonuterine diseases have been linked with poor reproductive efficiency. Fertilization is typically above 80% and does not seem to be the principal factor responsible for the low fertility in dairy cows. However, early embryonic development is compromised in high-producing dairy cows, as observed by most embryonic losses occurring during the first 2 weeks after fertilization and may be linked to compromised oocyte quality due to a poor follicular microenvironment, suboptimal reproductive tract environment for the embryo, and/or inadequate maternal-embryonic communication. These and other factors related to embryo development will be discussed.

  19. Analysis of heat stress in UK dairy cattle and impact on milk yields

    NASA Astrophysics Data System (ADS)

    Dunn, Robert J. H.; Mead, Naomi E.; Willett, Kate M.; Parker, David E.

    2014-05-01

    Much as humans suffer from heat-stress during periods of high temperature and humidity, so do dairy cattle. Using a temperature-humidity index (THI), we investigate the effect of past heatwaves in the UK on heat-stress in dairy herds. Daily THI data derived from routine meteorological observations show that during the summer, there has been an average of typically 1 day per year per station over the past 40 years when the THI has exceeded the threshold for the onset of mild heat-stress in dairy cattle. However, during the heatwaves of 2003 and 2006, this threshold was exceeded on typically 5 days on average in the Midlands, south and east of England. Most dairy cattle are in the west and north of the country and so did not experience the severest heat. Milk yield data in the south-west of England show that a few herds experienced decreases in yields during 2003 and 2006. We used the 11-member regional climate model ensemble with the A1B scenario from UKCP09 to investigate the possible future change in days exceeding the THI threshold for the onset of mild heat-stress. The number of days where the THI exceeds this threshold could increase to over 20 days yr-1 in southern parts of England by the end of the century.

  20. Perception of the importance of human-animal interactions on cattle flow and worker safety on Minnesota dairy farms.

    PubMed

    Sorge, U S; Cherry, C; Bender, J B

    2014-07-01

    Proper cattle-handling techniques (stockmanship) are important to ensure calm animals and a safe work environment for dairy workers on farm. The objectives of this study were to (1) assess Minnesota dairy herd owners' attitudes toward stockmanship, its perceived importance for cow comfort and worker health, and the establishment of calm cattle movement; and (2) identify current resources and methods of stockmanship training on Minnesota dairy farms. A stratified-random sample of Minnesota dairy farmers were contacted via mail to participate in a 28-question survey. One hundred eight bovine dairy producers participated. Most commonly, respondents learned their cattle handling skills from family members (42.6%) and 29.9% of producers had participated in previous stockmanship training. Producers thought that the skill of the human handler was the most important factor in establishing good cattle flow. Cattle-handling techniques was the third most common topic for new-employee orientation after training in milking parlor protocols and milking parlor disinfection. Time limitations and language barrier were considered serious challenges for worker training. Work-related injuries were responsible for lost work days in the previous year in 13.3% of dairy herds and 73.3% of those injuries occurred while working with cattle. Producers perceived that cattle-related injuries were predominantly the handler's fault: either because of not paying enough attention to the animal or due to poor cattle handling skills. Facility design was considered the least important for the occurrence of worker injuries. Although no causal inference can be made, herds that had workers who had previously participated in stockmanship training had a 810 ± 378 kg (mean ± standard error of the mean) higher rolling herd average than those that did not, even after adjusting for herd size and bulk tank somatic cell count. However, 50% of respondents were not interested in attending future stockmanship

  1. Case study of copper poisoning in a British dairy herd.

    PubMed

    Bidewell, C A; Drew, J R; Payne, J H; Sayers, A R; Higgins, R J; Livesey, C T

    2012-05-01

    Following the initial diagnosis of chronic copper poisoning (CCP), the copper (Cu) status of a British dairy herd was investigated. Eight fatal cases of CCP were identified over a 17-month period, from December 1999 to May 2001, involving seven Jersey cows and one Holstein-Friesian; seven cows were dry when CCP occurred. Case diagnostic criteria were necrotising hepatopathy associated with abnormally high liver and kidney Cu concentrations. Analysis of the ration for the high-yielding Jersey cow group revealed about 50 mg Cu/kg dry matter intake (DMI). Risk factors predisposing to fatal CCP were Jersey breed, previous high yield, first two weeks of the dry period and moderately high dietary Cu (greater than 40 mg Cu/kg DMI). PMID:22562897

  2. Associations between air emissions from sour gas processing plants and indices of cow retainment and survival in dairy herds in Alberta.

    PubMed

    Scott, H Morgan; Soskolne, Colin L; Lissemore, Kerry D; Martin, S Wayne; Shoukri, Mohamed M; Coppock, Robert W; Guidotti, Tee L

    2003-01-01

    This paper describes the results of an investigation into the effects of air emissions from sour gas processing plants on indices of retainment or survival of adult female dairy cattle on farms in Alberta; namely, the productive lifespan of individual animals, and annual herd-level risks for culling and mortality. Using a geographical information system, 2 dispersion models--1 simple and 1 complex--were used to assess historical exposures to sour gas emissions at 1382 dairy farm sites from 1985 through to 1994. Multivariable survival models, adjusting for the dependence of survival responses within a herd over time, as well as potential confounding variables, were utilized to determine associations between sour gas exposure estimates and the time from the first calving date to either death or culling of 150210 dairy cows. Generalized linear models were used to model the relationship between herd-level risks for culling and mortality and levels of sour gas exposure. No significant (P < 0.05) associations were found with the time to culling (n = 70052). However, both dispersion model exposure estimates were significantly associated (P < 0.05) with a decreased hazard for mortality; that is, in cases where cattle had died on-farm (n = 8743). There were no significant associations (P > 0.05) between herd culling risks and the 2 dispersion model exposure estimates. There was no measurable impact of plant emissions on the annual herd risk of mortality.

  3. Modeling of Mycobacterium avium subsp. paratuberculosis dynamics in a dairy herd: An individual based approach.

    PubMed

    Al-Mamun, Mohammad A; Smith, Rebecca L; Schukken, Ynte H; Gröhn, Yrjö T

    2016-11-01

    In the dairy industry, Johne's disease (JD), caused by Mycobacterium avium subsp. paratuberculosis (MAP) is one of the major investigated diseases. To date, researchers have suggested some control strategies for JD, such as test-and-cull based herd management, isolated calf rearing management, and vaccinations. Due to the slow progressing nature of MAP, tests with low diagnostic test sensitivity and specificity, and economic limitations, implementing these strategies has not resulted in elimination of MAP from farms. To date, no study has integrated detailed dairy herd dynamics with different MAP transmission routes. We have developed an individual-based dairy herd model by incorporating basic herd dynamics in a closed herd environment where no new animals have been bought from outside. The model considered three age groups of animals: calves, heifers and adults. It includes sequential life events of a dairy animal and such key dynamic processes of the dairy herd as lactation cycle, calving, voluntary waiting period, insemination, pregnancy, dry-off period and calf and heifer rearing. After initially validating that the model reproduced typical herd dynamics, it was extended by incorporating MAP infection dynamics, where each individual adult animal belonged to one of four infection compartments: susceptible, latent, low shedding and high shedding. The model includes two disease transmission routes: horizontal transmission (i.e., fecal-oral) and vertical transmission (i.e., in utero infection). The results confirm that this model can simulate a realistic dairy herd and that inclusion of the above-mentioned dynamic processes provides useful information about individual infected animals to farmers. Access to the individual animal information offers more validity to assessment of appropriate control strategies for an endemically MAP infected herd. This model can serve as an accurate and novel tool not only to better understand MAP dynamics, but is also valuable as an

  4. Therapeutic management of botulism in dairy cattle

    PubMed Central

    Pandian, S. Jegaveera; Subramanian, M.; Vijayakumar, G.; Balasubramaniam, G. A.; Sukumar, K.

    2015-01-01

    Aim: To report the successful recovery of few dairy cattle from botulism in response to a modified therapeutic strategy. Materials and Methods: Seventy four naturally-occurring clinical cases of bovine botulism encountered during the period of 2012-2014 which were confirmed by mouse lethality test became material for this study. Affected animals were made into three groups based on the treatment modifications made during the course of study. Results and Discussion: With the modified therapeutic regimen, 17 animals recovered after 7-10 days of treatment. Clinical recovery took 2-30 days. Animals which were not given intravenous fluid and calcium recovered uneventfully. Cattle which were already treated with intravenous fluids, calcium borogluconate, and antibiotics did not recover. They were either died or slaughtered for salvage. Conclusion: In cattle with botulism, administration of Vitamin AD3E and activated charcoal aid the clinical recovery. Besides, strictly avoiding anti-clostridial antibiotics, fluid therapy, and calcium therapy may facilitate the clinical recovery. Upon fluid administration, the pulmonary congestion existed in the ailing cattle might have worsened the anoxia. Administration of antibiotics like penicillin, aminoglycosides, and tetracyclines further worsen the neuronal paralysis by increasing the availability of botulinum neurotoxin. Cattle in early botulism have fair chances of recovery with the modified therapy. PMID:27047034

  5. Control of extensive chorioptic mange natural infection in lactating dairy cattle without milk withdrawal.

    PubMed

    Villarroel, Aurora; Halliburton, Megan K

    2013-08-01

    Dairy cattle are becoming increasingly complicated to treat in the USA due to the great limitation of approved drugs. Additionally, most drugs require withdrawal times for milk that are not viable for treating entire dairy herds. The objective of this field trial was to determine the efficacy of eprinomectin, one of only two parasiticides approved for lactating dairy cattle, for eradication of naturally occurring chorioptic mange on a commercial dairy farm. All animals present on the farm were treated on the same day and, later, new animals introduced to the premises were treated on arrival. All cows were re-treated at dry-off. Lesion scoring was performed five times over a period of 12 months. A reduction in the proportion of cows with lesions was apparent 3 months after treatment and, although the proportion stayed low, it increased again at 12 months post-treatment. Logistic regression to evaluate factors associated with the presence of mange lesions showed that older cows, late lactation, and recent treatment, were associated with presence of lesions. It also showed that multiple treatments (whole-herd treatment and at dry-off) helped to reduce the presence of lesions. No increase in milk production could be measured, but animal wellbeing improved. The results of this study show that chorioptic mange can be controlled in entire herds, although multiple treatments will be required to potentially eradicate the parasite. The value of the study is that it shows that mange can be controlled in dairy cattle with approved drugs, eliminating the need to use non-approved agents.

  6. Evidence of birth seasonality and clustering of Mycobacterium avium subspecies paratuberculosis infection in US dairy herds.

    PubMed

    Zare, Y; Shook, G E; Collins, M T; Kirkpatrick, B W

    2013-11-01

    Paratuberculosis (Johne's disease) is a contagious intestinal infection of ruminants caused by Mycobacterium avium subspecies paratuberculosis (MAP). In cattle, young calves are at the highest risk for acquiring the infection which occurs mainly through ingestion of MAP from contaminated milk, colostrum and feces or environmental contacts. Data consisted of birth dates and ELISA results of 8000 mature cows from 24 Jersey herds from throughout the US and 4 Wisconsin Holstein herds. Some herds also had complete fecal culture (FC) results. The first infection (case) definition (CD1) relied on only ELISA results. A second case definition (CD2) was used in which results of both ELISA and FC tests were considered: animals testing positive to either test were considered "test-positives" and cows testing negative to ELISA or to both ELISA and FC were regarded as "test-negatives". Objective one was to assess seasonality in birth of MAP-infected animals. The effects of age, breed, herd and season of birth (expressed as the sine and cosine functions of birth days within year) were examined using logistic regression. Age was significantly associated with the MAP infection status of dairy cows for both CDs (OR=1.11; 95% CI 1.09, 1.14; P<0.0001 for CD1; OR=1.16; 95% CI 1.08, 1.24; P<0.0001 for CD2). Season of birth had a significant effect on the risk of MAP infection based on CD1 (OR=0.79; 95% CI 0.71, 0.89; P<0.001 for cosine of birth days) with a peak in summer and a trough in winter based on the fitted model. Objective two was to assess whether test-positive animals were randomly distributed or were clustered by date of birth within herds. A temporal cluster analysis approach (scan statistic) implemented in SaTScan software was used for each case definition to detect clusters of birth cohorts using birthdates. Results identified significant clustering of MAP infection cases for CD1 in multiple herds (P<0.05). These results necessitate matching cases and controls of MAP

  7. A case-control study of risk factors for bovine cysticercosis in Danish cattle herds.

    PubMed

    Calvo-Artavia, F F; Nielsen, L R; Dahl, J; Clausen, D M; Graumann, A M; Alban, L

    2013-06-01

    Bovine cysticercosis (BC) is a zoonotic, parasitic infection in cattle. Under the current EU meat inspection regulation, every single carcass from all bovines above 6 weeks of age is examined for BC. This method is costly and makes more sense in countries with higher number of BC-infected animals than in countries with few lightly infected cases per year. The aim of the present case-control study was to quantify associations between potential herd-level risk factors and BC in Danish cattle herds. Risk factors can be used in the design of a risk-based meat inspection system targeted towards the animals with the highest risk of BC. Cases (n = 77) included herds that hosted at least one animal diagnosed with BC at meat inspection, from 2006 to 2010. Control herds (n = 231) consisted of randomly selected herds that had not hosted any animals diagnosed with BC between 2004 and 2010. The answers from a questionnaire and register data from the Danish Cattle Database were grouped into meaningful variables and used to investigate the risk factors for BC using a multivariable logistic regression model. Case herds were almost three times more likely than control herds to let all or most animals out grazing. Case herds were more than five times more likely than control herds to allow their animals access to risky water sources with sewage treatment plant effluent in proximity. Case herds were also more likely to share machinery or hire contractors than control herds. The risk decreased with increasing herd size probably because the larger herds generally tend to keep cattle indoors in Denmark. The results are useful to guide future data recording that can be supplied by the farmer as food chain information and then be used for differentiated meat inspection in low- and high-risk groups, enabling development of risk-based meat inspection systems.

  8. Prevalence and risk factors for udder cleft dermatitis in dairy cattle.

    PubMed

    Persson Waller, K; Bengtsson, M; Nyman, A-K

    2014-01-01

    Udder cleft dermatitis (UCD) is a skin lesion in dairy cattle mostly located at the anterior junction between the udder and the abdominal wall or between the front quarters. Relatively little is known about causative factors for UCD, and few studies have investigated prevalence and risk factors of UCD. Therefore, the aim of this study was to investigate the prevalence of UCD in a random sample of dairy herds with freestalls and milking parlors in a county of Sweden. Thirty dairy herds participated in the study. Each herd was visited once at milking, when every third cow was investigated for presence of UCD. Associations between UCD and milk production, breed, parity, days in milk, claw health, and udder health on the herd and cow levels were also investigated. In addition, a case-control study was performed in 6 herds with a high prevalence of UCD to investigate associations between udder conformation or mange and UCD. Udder cleft dermatitis was found in 18.4% of the 1,084 cows included in the study. The within-herd cow prevalence varied between zero and 39%, with an average of 18.5%. Risk factors for UCD at the herd level were a high proportion of Swedish Red cows and a high production level. At the cow level, breed, parity, and production level were identified as risk factors. The highest risk of having UCD was found in high-producing Swedish Red cows that had calved at least 3 times. Veterinary-treated clinical mastitis was associated with UCD, but cow composite somatic cell count was not. A strong anterior udder attachment was a protective factor, but signs of mange had no association with UCD. The primary cause of UCD is still unclear, and more research is needed to identify the best ways to prevent the development of this animal welfare problem.

  9. The use of computers in dairy herd health program: A review

    PubMed Central

    Lissemore, Kerry D.

    1989-01-01

    This review of the literature covers the changes in the approach to veterinary health management that led to the introduction of computerized herd health programs and the various other applications of the computer in the practice of dairy herd medicine. The role that production recording systems, mainframe computers, minicomputers, and microcomputers have played in the evolution of herd health programs are also reviewed. PMID:17423392

  10. Consequence of alternative standards for bulk tank somatic cell count of dairy herds in the United States

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Comparison of dairy operations failing compliance with current US and European Union (EU) standards for bulk-tank somatic cell count (BTSCC) as well as BTSCC standards proposed by 3 national organizations were evaluated using 2 populations of US dairy herds: Dairy Herd Improvement Association (DHI) ...

  11. Diquat poisoning of dairy cattle by topical application.

    PubMed Central

    Whiting, T L; Smyrl, T; Spearman, J G; Kernatz, S

    2001-01-01

    This case report describes poisoning of dairy cattle from a dermal challenge of 50 to 100 mg/kg body weight diquat. Five of 36 cattle exposed, demonstrated clinical signs of intoxication, dehydration, and death over 5 days. Diquat poisoning of cattle by the dermal route has not previously been reported. PMID:11665429

  12. Incidence of and risks associated with Giardia infections in herds on dairy farms in the New York City Watershed

    PubMed Central

    2010-01-01

    Background The primary aims of this study were to determine the incidence of Giardia infections in dairy herds on farms in the New York City Watershed region and to evaluate risk factors associated with infections. Because co-infections of Giardia and Cryptosporidium spp. are common in this population, we also evaluated the effect of herd infection status on Giardia infections. Methods Farms were grouped into three cohorts based on their prior infection status with Giardia and/or Cryptosporidium spp. The sampling plan included collecting fecal samples from all calves below 30 days of age and proportional sampling of calves, young stock, and adults. A total of 10,672 fecal samples were collected and analyzed for the presence of Giardia cysts using zinc sulfate flotation. Herds enrolled in the study were sampled seasonally for a study period of two years. The probability of shedding cysts past a certain age and the factors that influenced the likelihood of shedding were evaluated using survival analysis. Linear regression was used to evaluate factors that were associated with the intensity of shedding. Results The majority of Giardia infections occurred in calves within their first 180 days of age, with the most number of calves shedding Giardia cysts between 11 and 20 days of age. The incidence of shedding of Giardia cysts ranged from 0.0004 per animal day for cattle in the low risk cohort to 0.0011 per animal day for cattle in the high risk cohort. The likelihood of shedding was influenced by the prior infection status of the herd and the season of collection. Infected animals shed on average 9,658 cysts/gram and the intensity of shedding Giardia cysts varied significantly with the age (p < 0.0001) and the season of collection (p = 0.0151 for Spring). Conclusion Giardia infections are common in dairy herds in the New York City watershed, particularly in calves less than 6 months of age. Seasonality may be an important factor in the perpetuation of infections based

  13. Iodine concentrations in milk of dairy cattle fed various amounts of iodine as ethylenediamine dihydroiodide.

    PubMed

    Berg, J N; Padgitt, D; McCarthy, B

    1988-12-01

    Due to concerns about high I in milk, the dairy industry has proposed a voluntary standard of 500 micrograms of I/L as the maximum allowable I in milk sold for processing and human consumption. This study was undertaken to determine the amount of ethylenediamine dihydroiodide that could be fed to dairy cattle without exceeding this standard. Various amounts (0 to 45 mg/head per d) of the I compound were fed to a commercial dairy herd for 50 wk. Individual and bulk milk samples were analyzed for total iodine. Milk I in herd bulk milk was directly correlated (r = .92) with the amounts fed. However, the correlation of milk I of individual cows was not as high (r = .66), indicating some individual variation in metabolism and secretion of the I into the mammary gland. Milk production and number of lactations did not correlate with I in milk. Regression analysis indicated that 25 to 30 mg of ethylenediamine dihydroiodide per day can be fed to dairy cattle receiving a diet otherwise low in I without exceeding a 500 micrograms concentration in milk.

  14. Mycobacterium avium subsp. paratuberculosis Antibody Response, Fecal Shedding, and Antibody Cross-Reactivity to Mycobacterium bovis in M. avium subsp. paratuberculosis-Infected Cattle Herds Vaccinated against Johne's Disease

    PubMed Central

    Hovingh, Ernest; Linscott, Rick; Martel, Edmond; Lawrence, John; Wolfgang, David; Griswold, David

    2014-01-01

    Vaccination for Johne's disease with killed inactivated vaccine in cattle herds has shown variable success. The vaccine delays the onset of disease but does not afford complete protection. Johne's disease vaccination has also been reported to interfere with measurements of cell-mediated immune responses for the detection of bovine tuberculosis. Temporal antibody responses and fecal shedding of Mycobacterium avium subsp. paratuberculosis, the causative agent of Johne's disease, were measured in 2 dairy cattle herds using Johne's disease vaccine (Mycopar) over a period of 7 years. Vaccination against Johne's disease resulted in positive serum M. avium subsp. paratuberculosis antibody responses in both herds, and the responses persisted in vaccinated cattle up to 7 years of age. Some vaccinated animals (29.4% in herd A and 36.2% in herd B) showed no serological reactivity to M. avium subsp. paratuberculosis. M. avium subsp. paratuberculosis-specific antibody responses were also detected in milk from Johne's disease-vaccinated animals, but fewer animals (39.3% in herd A and 49.4% in herd B) had positive results with milk than with serum samples. With vaccination against M. avium subsp. paratuberculosis, fecal shedding in both dairy herds was reduced significantly (P < 0.001). In addition, when selected Johne's disease-vaccinated and -infected animals were investigated for serological cross-reactivity to Mycobacterium bovis, no cross-reactivity was observed. PMID:24623626

  15. Invasion and transmission of Salmonella Kentucky in an adult dairy herd using approximate Bayesian computation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An outbreak of Salmonella Kentucky followed by a high level of sustained endemic prevalence was recently observed in a US adult dairy herd enrolled in a longitudinal study involving intensive fecal sampling. To understand the invasion ability and transmission dynamics of Salmonella Kentucky in dairy...

  16. Identifying risk factors associated with lameness in pasture-based dairy herds.

    PubMed

    Ranjbar, S; Rabiee, A R; Gunn, A; House, J K

    2016-09-01

    Lameness is a significant welfare concern for dairy farmers and a major contributing economic loss to the dairy industry. Information is limited on environmental and managerial risk factors associated with lameness in Australian dairy herds. The objective of this study was to explore and quantify the environmental and management risk factors associated with lameness in pasture-based dairy herds. A cross-sectional study was conducted in 63 pasture-based dairy herds between 2011 and 2014, where all lactating cows were locomotion scored (scale 1-4) during a single visit. Environmental and management variables, such as length of main track and animal handling practices, were recorded during the visit. The prevalence of lameness was measured for each farm and associated risk factors were analyzed using a Generalized Linear Model, where farm was the unit of analysis. Estimated average prevalence of lameness was 18.9% (range 5 to 44.5%). The prevalence of lameness was associated with the amount of rainfall during the 30 d before the farm assessment, smoothness of concrete surface and available space per cow in the holding yard, and length of feed-pad available per cow. Inappropriate handling of cows on the track (e.g., causing sideways pushing among cows) was also a contributing risk factor to high prevalence of lameness in these dairy herds. The findings of this study suggest that by managing several environmental and farming practices, producers can reduce the prevalence of lameness, leading to improved productivity of their herds. PMID:27394954

  17. Identifying risk factors associated with lameness in pasture-based dairy herds.

    PubMed

    Ranjbar, S; Rabiee, A R; Gunn, A; House, J K

    2016-09-01

    Lameness is a significant welfare concern for dairy farmers and a major contributing economic loss to the dairy industry. Information is limited on environmental and managerial risk factors associated with lameness in Australian dairy herds. The objective of this study was to explore and quantify the environmental and management risk factors associated with lameness in pasture-based dairy herds. A cross-sectional study was conducted in 63 pasture-based dairy herds between 2011 and 2014, where all lactating cows were locomotion scored (scale 1-4) during a single visit. Environmental and management variables, such as length of main track and animal handling practices, were recorded during the visit. The prevalence of lameness was measured for each farm and associated risk factors were analyzed using a Generalized Linear Model, where farm was the unit of analysis. Estimated average prevalence of lameness was 18.9% (range 5 to 44.5%). The prevalence of lameness was associated with the amount of rainfall during the 30 d before the farm assessment, smoothness of concrete surface and available space per cow in the holding yard, and length of feed-pad available per cow. Inappropriate handling of cows on the track (e.g., causing sideways pushing among cows) was also a contributing risk factor to high prevalence of lameness in these dairy herds. The findings of this study suggest that by managing several environmental and farming practices, producers can reduce the prevalence of lameness, leading to improved productivity of their herds.

  18. New findings of Enterocytozoon bieneusi in beef and dairy cattle in Brazil.

    PubMed

    da Silva Fiuza, Vagner Ricardo; Lopes, Carlos Wilson Gomes; de Oliveira, Francisco Carlos Rodrigues; Fayer, Ronald; Santin, Monica

    2016-01-30

    Microsporidia are widely recognized as important human pathogens with Enterocytozoon bieneusi as the most common species infecting humans and animals, including cattle. Although Brazil has the second largest cattle herd in the world and it is the largest exporter of beef there are no data on the presence or impact of E. bieneusi on this important population. To fill this knowledge gap, fecal specimens were collected from 452 cattle from pre-weaned calves to adult cattle in the state of Rio de Janeiro. Host factors including age, gender, dairy/beef, body composition, and fecal consistency were included in the study. Using molecular methods, E. bieneusi was found in 79/452 (17.5%) fecal specimens. This represents the first report of this parasite in Brazilian cattle. A significantly higher prevalence was found in calves less than 2 months of age (27.6%) and those 3-8 months of age (28.8%) versus heifers (14.1%) and adults (1.4%) (P<0.05). Dairy cattle (26.2%) had a higher prevalence than beef cattle (9.7%) (P<0.001). No correlation was found between infection and gender, body composition, and fecal consistency. Molecular characterization of the internal transcribed spacer (ITS) revealed 12 genotypes; five previously reported in cattle (BEB4, BEB8, D, EbpA and I), and seven novel genotypes (BEB11-BEB17). A phylogenetic analysis showed that 6 genotypes (D, EbpA, BEB12, BEB13, BEB15, and BEB16) identified in 18 animals clustered within the designated zoonotic Group 1 while the other 6 genotypes (I, BEB4, BEB8, BEB11, BEB14, BEB17) identified in 61 animals clustered within Group 2. The identification of genotypes in Brazilian cattle that have previously been reported in humans highlights the potential risk of zoonotic transmission and suggests that the role of cattle in transmission of human infections requires further study.

  19. Seroconversion to bovine viral diarrhoea virus and infectious bovine rhinotracheitis virus in dairy herds of Michoacan, Mexico.

    PubMed

    Segura-Correa, José C; Solorio-Rivera, José L; Sánchez-Gil, Laura G

    2010-02-01

    Bovine viral diarrhoea virus (BVDV) and infectious bovine rhinotracheitis virus (IBRV) are important viral diseases around the world. The objective of this study was to estimate the incidence of seroconversion to BVDV and IBRV and to identify associated risk factors in dairy herds of Michoacan, Mexico. The longitudinal study included 62 herds and ran from December 2001 to November 2002. The total number of animals enrolled and completing the study were 392 and 342 animals for BVDV and 925 and 899 animals for IBRV. Animals were tested monthly for 12 months, for the presence of antibodies. Risk factors were: herd size (2-9, 10-25 and 26-55 animals), herd serostatus (seropositive or seronegative, only for IBRV), age group of the animal (6 to 12, 13 to 24, 25 to 48 and > 48 months) and animal origin (born in farm, purchased). The cumulative incidences for BVDV and IBRV were 16.4% and 3.4%, respectively; whereas, the incidence density rates for BVDV and IBRV were 15.9 and 2.9 per 1000 animal-months at risk, respectively. Seroconversion curves were statistically different for age group for BVDV and IBRV and for herd status for IBR. The relatively high incidence of seroconversion for BVDV suggests that a successful control programme should be oriented towards the identification and elimination of the PI animals and towards avoiding the introduction of PI cattle to the farm. The scenario of IBRV is favourable to implement a programme directed to reduce the number of new seropositive herds.

  20. Seroprevalence of Neospora caninum in dairy cattle from north-west and centre of Romania

    PubMed Central

    Gavrea, R.R.; Iovu, A.; Losson, B.; Cozma, V.

    2011-01-01

    Neosporosis is a disease that mainly affects cattle in both dairy and beef herds. The main definitive host of this parasite is the dog. Since 1984 and its first description a large number of data were published worldwide on this parasite. In Romania, the research regarding this parasite is limited. The purpose of this study was to determine the seroprevalence of Neospora caninum infection in dairy cattle from six regions in north-western Romania and to evaluate the intensity of infection in different animals groups. A total number of 901 samples (862 sera from adult cows and 39 sera from calves) were collected from dairy farms and were screened for the presence of specific IgG anti-bodies using an enzyme-linked immunosorbent assay (ELISA). The overall seroprevalence for neosporosis was 34.6%. In adult cows and calves seroprevalences reached 34.8% (300/862) and 30.8% for calves (12/39) respectively. In cattle which had previously aborted, seroprevalence was 40.9%. These results indicate that N. caninum infection is widespread among animals reared in dairy systems from Romania and a program for farmer training and a strategy for reducing the economic impact of the disease are needed. PMID:22091468

  1. Reducing environmental impact of dairy cattle: a Czech case study.

    PubMed

    Havlikova, Martina; Kroeze, Carolien

    2010-07-01

    We analyze options to reduce the future environmental impact of dairy cattle production, using an optimization model (DAIRY) applied to the Czech Republic. The DAIRY model can be used to calculate the overall environmental impact (OEI). We show that aquatic eutrophication and global warming are the 2 most important problems caused by dairy cattle. These problems are largely caused by nitrate leaching and emissions from animal housing. The DAIRY model indicates that the costs of reducing the OEI in 2020 by 20% are 12 MEuro. It is most cost effective to achieve this reduction by improving the efficiency of animal manure used as fertilizer. We tested the sensitivity of the model to assumptions about the following: 1) the relative importance of environmental problems as expressed in weighting factors, and 2) future cattle numbers and milk yield per milking cow. The first case indicates that disagreement on which problem is most urgent need not lead to disagreement about policies to be undertaken. Regardless of the weighting factors used, aquatic eutrophication and global warming are the most important problems. However, the overall costs of reducing the OEI differ with alternative sets of weighting factors, because the costs of emission reduction differ among pollutants. The second case shows that the DAIRY model results are more sensitive to changes in cattle numbers than to changes in milk yield. This study is the first integrated assessment of dairy cattle production for a Central European country and illustrates how systematic analyses may help to find optimal solutions.

  2. Antibiotic use in dairy herds in the Netherlands from 2005 to 2012.

    PubMed

    Kuipers, A; Koops, W J; Wemmenhove, H

    2016-02-01

    The aim of this study was to examine the variation in antibiotic use and the effects of external factors on trends in antibiotic use at the herd level by using the number of daily dosages as an indicator for antibiotic use. For this purpose, antibiotic use was analyzed in 94 dairy herds in the Netherlands from 2005 to 2012. The herds were divided into 3 groups of farmers: one group was guided in their antibiotic use from 2008 to 2010 as part of the project, whereas the other 2 groups were not actively guided. The farms were located in 10 of the 12 provinces and were clients of 32 of the 300 veterinary practices that treat cattle. Sales invoices from the veterinary practices provided the antibiotic and cost data for the participating farmers. The number of animal-defined daily dosages (ADDD) indicates the number of days per year that the average cow in a herd is given antibiotic treatment. The average ADDD for all farms from 2005 to 2012 was 5.86 (standard deviation=2.14); 68% of ADDD were used for udder health, 24% for clinical mastitis and 44% for dry-cow therapy. Variation in ADDD among herds decreased during the study period. The trend in ADDD can be described as having 3 phases: (1) a period of increasing use coinciding with little public concern about antibiotic use (2005-2007), (2) a period of growing awareness and stabilization of use (2007-2010), and (3) a period of decreasing use coinciding with increasing societal concerns (2010-2012). The greatest reduction in use was for drugs other than those used to treat the udder. Drug use for mastitis treatment fell considerably in the final year of the study period, whereas farmers were reluctant to reduce use for dry-cow therapy. Almost 40% of the herds were given less than 2.5 ADDD for dry-cow therapy, which is equivalent to 2.5 tubes per average cow in the herd, and 20% used more than 3 tubes per cow. Use of third- and fourth-generation cephalosporins and fluoroquinolones dropped from 18% of ADDD during 2005 to

  3. Improving fertility of dairy cattle using translational genomics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Selection for higher milk production in United States dairy cattle has been very successful during the past 50 years, however today’s lactating dairy cows exhibit a high incidence of subfertility and infertility with a national pregnancy rate of only 15%. An integrated approach to improve fertility ...

  4. Time-to-event analysis of predictors for recovery from Salmonella Dublin infection in Danish dairy herds between 2002 and 2012.

    PubMed

    Nielsen, Liza Rosenbaum; Dohoo, Ian

    2013-07-01

    Salmonella Dublin infections reduce gross margins and compromise animal health and welfare in dairy cattle herds. Despite on-going control efforts in several countries the duration and risk factors of a persistent infection have been difficult to study due to a lack of suitable data. This study utilised the unique opportunity to extract systematically collected repeated bulk-tank milk antibody measurements from all the Danish dairy herds during a 10-year period to perform a time-to-event analysis of the factors that affect the duration of test-positivity and the hazards of recovery from S. Dublin at herd level. Recovery was defined as a shift from test-positive to test-negative between two year-quarters followed by at least three more test-negative year-quarters. The average duration of infection was approximately 2 years. Predictors of recovery were tested in a multivariable Cox proportional hazard model allowing herds to recover from infection multiple times over the 10-year surveillance period. The model results were based on 36,429 observations with data on all the predictors, representing 3563 herds with a total of 3246 recoveries. Sixty-seven herds (2.4%) remained test-positive throughout the study period. The rest of the 317 herds that did not have any recoveries were censored, mainly due to a cessation of milk production. Prior recovery from test-positivity turned out not to be a significant predictor of recovery in the model. The effect of the duration of infection on the conditional probability of recovery (i.e. the hazard) was time-dependent: early in the study period, long durations of infection were predictive of a low hazard of recovery. Later in the control programme the effect of duration of infection was reduced indicating a desired effect of an intensified control programme. There was an increasing tendency towards longer durations and lower hazard of recovery with: (i) increasing herd sizes, (ii) increasing bulk-tank milk somatic cell counts

  5. The cost of a case of subclinical ketosis in Canadian dairy herds.

    PubMed

    Gohary, Khaled; Overton, Michael W; Von Massow, Michael; LeBlanc, Stephen J; Lissemore, Kerry D; Duffield, Todd F

    2016-07-01

    The objective of this study was to develop a model to estimate the cost of a case of subclinical ketosis (SCK) in Canadian dairy herds. Costs were derived from the default inputs, and included increased clinical disease incidence attributable to SCK, $76; longer time to pregnancy, $57; culling and death in early lactation attributable to SCK, $26; milk production loss, $44. Given these figures, the cost of 1 case of SCK was estimated to be $203. Sensitivity analysis showed that the estimated cost of a case of SCK was most sensitive to the herd-level incidence of SCK and the cost of 1 day open. In conclusion, SCK negatively impacts dairy herds and losses are dependent on the herd-level incidence and factors included in the calculation. PMID:27429460

  6. An 8-year longitudinal sero-epidemiological study of bovine leukaemia virus (BLV) infection in dairy cattle in Turkey and analysis of risk factors associated with BLV seropositivity.

    PubMed

    Şevik, Murat; Avcı, Oğuzhan; İnce, Ömer Barış

    2015-04-01

    Enzootic bovine leukosis (EBL) which is caused by bovine leukaemia virus (BLV) has an important economic impact on dairy herds due to reduced milk production and restrictions on livestock exports. This study was conducted to determine the BLV infection status in Central Anatolia Region of Turkey, an important milk production centre, and to examine the risk factors such as purchasing cattle, increasing cattle age, cattle breed and herd size associated with transmission of BLV infection. To estimate the rate of BLV infection, a survey for specific antibodies in 28,982 serum samples from animals belonging to 1116 different herds situated in Central Anatolia Region of Turkey were tested from January 2006 to December 2013. A generalized mixed linear model was used to evaluate the risk factors that influenced BLV seroprevalence. Antibodies against BLV were detected in 431 (2.28 %) of 18,822 Holstein and 29 (0.28 %) of 10,160 Brown Swiss cows. Among 1116 herds, 132 herds (11.82 %) had one or more positive animals. Also results of our study show that the prevalence of BLV infection increased from 2006 to 2011, and it tends to reduce with BLV control programme. Furthermore, we found positive associations between percentage of seropositive animal and increasing cattle age, herd size, cattle breed and purchased cattle. Age-specific prevalence showed that BLV prevalence increased with age. These factors should be taken into consideration for control of BLV infection.

  7. Streptococcus agalactiae in the environment of bovine dairy herds--rewriting the textbooks?

    PubMed

    Jørgensen, H J; Nordstoga, A B; Sviland, S; Zadoks, R N; Sølverød, L; Kvitle, B; Mørk, T

    2016-02-29

    Many free-stall bovine dairy herds in Norway fail to eradicate Streptococcus agalactiae despite long-term control measures. In a longitudinal study of 4 free-stall herds with automatic milking systems (AMS), milk and extramammary sites were sampled 4 times with 1-2 month intervals. Composite milk, rectal- and vaginal swabs were collected from dairy cows; rectal swabs from heifers and young stock; rectal- and tonsillar swabs from calves; and environmental swabs from the AMS, the floors, cow beds, watering and feeding equipment. A cross sectional study of 37 herds was also conducted, with 1 visit for environmental sampling. Fifteen of the herds were known to be infected with S. agalactiae while the remaining 22 had not had evidence of S. agalactiae mastitis in the preceding 2 years. All samples were cultured for S. agalactiae, and selected isolates (n=54) from positive herds were genotyped by Multi Locus Sequence Typing (MLST). Results show that the bovine gastrointestinal tract and the dairy cow environment are reservoirs of S. agalactiae, and point to the existence of 2 transmission cycles; a contagious transmission cycle via the milking machine and an oro-fecal transmission cycle, with drinking water as the most likely vehicle for transmission. Ten sequence types were identified, and results suggest that strains differ in their ability to survive in the environment and transmit within dairy herds. Measures to eradicate S. agalactiae from bovine dairy herds should take into account the extra-mammary reservoirs and the potential for environmental transmission of this supposedly exclusively contagious pathogen.

  8. Streptococcus agalactiae in the environment of bovine dairy herds--rewriting the textbooks?

    PubMed

    Jørgensen, H J; Nordstoga, A B; Sviland, S; Zadoks, R N; Sølverød, L; Kvitle, B; Mørk, T

    2016-02-29

    Many free-stall bovine dairy herds in Norway fail to eradicate Streptococcus agalactiae despite long-term control measures. In a longitudinal study of 4 free-stall herds with automatic milking systems (AMS), milk and extramammary sites were sampled 4 times with 1-2 month intervals. Composite milk, rectal- and vaginal swabs were collected from dairy cows; rectal swabs from heifers and young stock; rectal- and tonsillar swabs from calves; and environmental swabs from the AMS, the floors, cow beds, watering and feeding equipment. A cross sectional study of 37 herds was also conducted, with 1 visit for environmental sampling. Fifteen of the herds were known to be infected with S. agalactiae while the remaining 22 had not had evidence of S. agalactiae mastitis in the preceding 2 years. All samples were cultured for S. agalactiae, and selected isolates (n=54) from positive herds were genotyped by Multi Locus Sequence Typing (MLST). Results show that the bovine gastrointestinal tract and the dairy cow environment are reservoirs of S. agalactiae, and point to the existence of 2 transmission cycles; a contagious transmission cycle via the milking machine and an oro-fecal transmission cycle, with drinking water as the most likely vehicle for transmission. Ten sequence types were identified, and results suggest that strains differ in their ability to survive in the environment and transmit within dairy herds. Measures to eradicate S. agalactiae from bovine dairy herds should take into account the extra-mammary reservoirs and the potential for environmental transmission of this supposedly exclusively contagious pathogen. PMID:26854346

  9. Economic effects of exposure to bovine viral diarrhea virus on dairy herds in New Zealand.

    PubMed

    Heuer, C; Healy, A; Zerbini, C

    2007-12-01

    The economic loss to dairy farmers associated with bovine viral diarrhea virus (BVDV) is believed to be high in New Zealand, but no estimates are yet available. The aim was therefore to estimate the economic loss associated with BVDV in dairy herds in New Zealand. Bulk tank milk (BTM) from a random sample of 590 herds from the Northland, Bay of Plenty, and Waikato regions was tested for antibody against BVDV. The inhibition percentage (sample to positive ratio), based on a threshold validated in an earlier study, was used to indicate herd-level infection. Herd reproductive indices, herd lactation-average somatic cell counts, and herd average production of milk solids were regressed on BTM inhibition percentage. Herd averages of the overall annual culling rate, the rate of culling because of failure to conceive, the proportion of physiological inter-service intervals, the first-service conception rate, the pregnancy rate at the end of mating, and somatic cell counts were not associated with BVDV antibody in BTM. Abortion rates, rates of calving induction, the time from calving to conception, and the number of services per conception increased, however, whereas milk production decreased with increasing BVDV antibody in BTM. The results indicated significant reproductive and production loss associated with the amount of BVDV antibody in BTM. Total loss attributable to infection with BVDV was similar to reports from other countries and estimated as NZ$87 per cow and year in affected herds, and NZ$44.5 million per year for the New Zealand dairy industry based on an estimated 14.6% affected herds. The loss estimate excludes added cost and negative consequences with respect to animal welfare attributable to increased induction rates, and a greater incidence of production disease because of BVD-induced immune suppression.

  10. Temporal trends in reproductive performance in Irish dairy herds and associated risk factors

    PubMed Central

    2004-01-01

    Irish dairy herd fertility has been declining since the 1980s. The extent, nature and causes of this decline in fertility and the current status of Irish dairy herd fertility were described. An increase in calving interval of approximately one day per year has been recorded. The principal components of this trend have been an increased incidence of postpartum endocrinopathies, reduced expression of oestrus and a fall in conception rate. Both submission rate and calving-to-service interval have increased slightly over time. Significant risk factors associated with these trends have been strain substitution within the Holstein-Friesian breed and single trait selection for milk production. Critically, these changes have been reflected in loss of body condition. Contributory factors included increased herd size and possibly increased use of DIYAI. The most recent Irish study showed that 48% of cows conceived to first service and 14% of cows were not pregnant at the end of the industry-average 15-week spring breeding season. However, the top quartile of herds achieved a first-service conception rate of 59%, illustrating the wide variation between herds. These phenotypic trends were attributed to both genetic and environmental factors and their interactions. Recent Irish dairy herd fertility performance falls short of the targets set for seasonal compact calving. PMID:21851656

  11. Does milk yield reflect the level of welfare in dairy herds?

    PubMed

    Coignard, Maud; Guatteo, Raphaël; Veissier, Isabelle; Lehébel, Anne; Hoogveld, Charlotte; Mounier, Luc; Bareille, Nathalie

    2014-01-01

    Under the assumption that milk yield may be reduced in herds with impaired welfare, the present study aimed at investigating whether milk yield could be used as a reliable indicator of welfare. In 125 commercial French dairy herds, the association between the welfare of the herd (evaluated using the Welfare Quality assessment protocol) and cow milk yield was investigated using linear mixed models. Positive associations were identified between milk yield and low aggressions between cows and good emotional state of the herd but there was a negative association with good health assessed through the occurrence of diseases and injuries. These opposite associations resulted in no association with the overall welfare of the herd. Milk yield should not therefore be used as an indicator of overall welfare.

  12. BVDV and BHV-1 Infections in Dairy Herds in Northern and Northeastern Thailand

    PubMed Central

    Kampa, J; Ståhl, K; Moreno-López, J; Chanlun, A; Aiumlamai, S; Alenius, S

    2004-01-01

    Bulk milk samples from 220 dairy herds were collected at 9 public milk collection centres in the northeastern and northern Thailand, and a subset of 11 herds was selected for individual testing. The samples were tested for presence of antibodies to BVDV and BHV-1 using an indirect ELISA. The results from the bulk milk testing demonstrated a moderate level of exposure to BVDV and BHV-1 (73% and 67%, respectively). However, the low proportion of herds with high BVDV antibody-levels (13%) and the low within-herd seroprevalence of BVDV and BHV-1 in the 11 herds (24% and 5%, respectively), particularly among the young stock (15% and 0%, respectively), demonstrated a low prevalence of active BVDV infection and a low rate of reactivation of latent BHV-1. The presence of a self-clearance process was also indicated by the results from the individual testing. Moreover, a surprisingly low prevalence of BVDV and BHV-1 antibody-positive herds at one of the milk centres was found. This centre was established 5–10 years before the others. Our impression is that this reflects the self-clearance process, where consecutive replacement of imported infected animals without further spread has resulted in a nearly total elimination of the infections. Based on our experiences and on these results we are convinced that this process can continue if there is awareness of herd biosecurity. This is especially important in the context of a future intensification of the dairy production. PMID:15663078

  13. Relationships between milk production, ovarian function and fertility in high-producing dairy herds in north-eastern Spain.

    PubMed

    Yániz, J; López-Gatius, F; Bech-Sàbat, G; García-Ispierto, I; Serrano, B; Santolaria, P

    2008-10-01

    In the dairy industry worldwide, reproductive disorders are a major cause of economic losses and a challenge to scientists and technicians. In recent decades, declining fertility and increasing milk production have been widely reported in dairy cattle. In this article, the relationships between milk production, ovarian disorders and fertility in high-producing dairy herds are briefly described. We carried out a retrospective study of 23 204 lactations included in a reproductive control programme in north-eastern Spain, a geographical area experiencing both warm and cool conditions. The data were collected between 1991 and 2007 and refer to cows first inseminated or examined 45-80 days postpartum in five well-managed, commercial, Holstein-Friesian high-producing dairy herds. Ovarian disorders were classified as ovarian inactivity or hypofunction, cystic ovarian disease, sub-oestrus or silent ovulation and sub-luteal function. Ovarian hypofunction and milk production increased throughout the study period and there was a decrease in the pregnancy rate to first artificial insemination (AI). Cows suffering ovarian hypofunction were efficiently treated using combined progestagen-prostaglandin treatments. The incidence of ovarian cysts showed little variation with time. Treatment of this syndrome may include different GnRH-based treatments or manual rupture. During the last 5 years, sub-oestrus was the predominant dysfunction (42.1%) compared with the cystic (6.3%) and ovarian hypofunction (12%) forms. Response of sub-oestrous cows to treatment with luteolitic agents was usually higher than 60%. Ovarian function and fertility were dramatically impaired during the warm period. However, during the later years of the study, the inclusion of fans and water sprinklers for the warm season appeared to overcome the seasonal effect on fertility. PMID:18803755

  14. Opportunities for improving milk production efficiency in dairy cattle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Increasing feed costs and the desire to improve environmental stewardship have stimulated renewed interest in improving feed efficiency of livestock, including that of U.S. dairy herds. For instance, USDA cost projections for corn and soybean meal suggest a 20% increase over 2010 pricing for a 16% p...

  15. Opportunities for improving milk production efficiency in dairy cattle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Increasing feed costs and the desire to improve environmental stewardship have stimulated interest in improving feed efficiency of livestock, including that of U.S. dairy herds. For instance, USDA cost projections for corn and soybean meal suggest a 20% increase over 2010 pricing for a 16% protein ...

  16. Use of ionophores in lactating dairy cattle: a review.

    PubMed Central

    Duffield, T F; Bagg, R N

    2000-01-01

    Ionophores are feed additives that alter rumen microbial populations through ion transfer across cell membranes. Although ionophores have been used widely in the beef industry for improved feed efficiency and control of coccidiosis, there has been limited use by the dairy industry. In Canada, the label warning prohibiting the use of monensin premix in lactating dairy cattle was removed in June 1996. Following this, in December 1997, a controlled release capsule containing monensin was approved for use in dairy cattle as an aid to prevent subclinical ketosis. Monensin may have several advantages for dairy cattle, including improved energy metabolism, increased milk production, and altered milk components. This literature review was primarily conducted in 1996 by using the Agricola and CAB search databases. Other relevant articles published since the search (up to 1998) have been added. This review will provide practitioners with relevant references in the published literature regarding ionophore use in dairy cattle. It should also give some guidance as to what effects might be anticipated with the use of ionophores in lactating dairy animals. PMID:10816832

  17. Reproductive management practices and performance of Canadian dairy herds using automated activity-monitoring systems.

    PubMed

    Neves, R C; LeBlanc, S J

    2015-04-01

    The objectives of this study were to describe the characteristics and motivations of producers who had implemented automated activity-monitoring (AAM) systems and to compare herd reproductive performance before and after the implementation of an AAM system and between herds with AAM and herds managing reproduction based on timed artificial insemination (TAI) or based on other programs. Freestall dairy herds located in Ontario and the western provinces of Canada and enrolled in Dairy Herd Improvement were surveyed through a mail questionnaire between April and July 2010. The data describe the characteristics and reproductive management practices of herds using AAM systems. A total of 505 questionnaires (29%) were returned. On average, 21-d pregnancy risk, conception risk, and 21-d insemination risk did not differ between herds managing reproduction based on an AAM system (18, 39, and 50%, respectively) or a TAI-based program (17, 38, and 49%, respectively). Herds that implemented an AAM system had a significant increase in annual pregnancy risk, from 15 to 17%, and insemination risk increased from 42 to 50%, whereas conception risk was unchanged (37 and 35%) following adoption of the system. The majority of respondents with AAM systems first used the system to manage reproduction in lactating cows. Most herds with AAM were performing artificial insemination twice per day, most commonly with an interval from the estrus alarm to artificial insemination of 7 to 12 h. The most commonly reported reason to adopt an AAM system was a desire to improve reproductive performance. These results support the findings from randomized trials that AAM-based programs can yield comparable reproductive performance to TAI-based programs.

  18. Molecular Epidemiology of Streptococcus uberis Clinical Mastitis in Dairy Herds: Strain Heterogeneity and Transmission.

    PubMed

    Davies, P L; Leigh, J A; Bradley, A J; Archer, S C; Emes, R D; Green, M J

    2016-01-01

    Multilocus sequence typing was successfully completed on 494 isolates of Streptococcus uberis from clinical mastitis cases in a study of 52 commercial dairy herds over a 12-month period. In total, 195 sequence types (STs) were identified. S. uberis mastitis cases that occurred in different cows within the same herd and were attributed to a common ST were classified as potential transmission events (PTEs). Clinical cases attributed to 35 of the 195 STs identified in this study were classified PTE. PTEs were identified in 63% of the herds. PTE-associated cases, which include the first recorded occurrence of that ST in that herd (index case) and all persistent infections with that PTE ST, represented 40% of all the clinical mastitis cases and occurred in 63% of the herds. PTE-associated cases accounted for >50% of all S. uberis clinical mastitis cases in 33% of the herds. Nine STs (ST-5, -6, -20, -22, -24, -35, -233, -361, and -512), eight of which were grouped within a clonal complex (sharing at least four alleles), were statistically overrepresented (OVR STs). The findings indicate that 38% of all clinical mastitis cases and 63% of the PTEs attributed to S. uberis in dairy herds may be caused by the nine most prevalent strains. The findings suggest that a small subset of STs is disproportionally important in the epidemiology of S. uberis mastitis in the United Kingdom, with cow-to-cow transmission of S. uberis potentially occurring in the majority of herds in the United Kingdom, and may be the most important route of infection in many herds. PMID:26491180

  19. Molecular Epidemiology of Streptococcus uberis Clinical Mastitis in Dairy Herds: Strain Heterogeneity and Transmission

    PubMed Central

    Leigh, J. A.; Bradley, A. J.; Archer, S. C.; Emes, R. D.; Green, M. J.

    2015-01-01

    Multilocus sequence typing was successfully completed on 494 isolates of Streptococcus uberis from clinical mastitis cases in a study of 52 commercial dairy herds over a 12-month period. In total, 195 sequence types (STs) were identified. S. uberis mastitis cases that occurred in different cows within the same herd and were attributed to a common ST were classified as potential transmission events (PTEs). Clinical cases attributed to 35 of the 195 STs identified in this study were classified PTE. PTEs were identified in 63% of the herds. PTE-associated cases, which include the first recorded occurrence of that ST in that herd (index case) and all persistent infections with that PTE ST, represented 40% of all the clinical mastitis cases and occurred in 63% of the herds. PTE-associated cases accounted for >50% of all S. uberis clinical mastitis cases in 33% of the herds. Nine STs (ST-5, -6, -20, -22, -24, -35, -233, -361, and -512), eight of which were grouped within a clonal complex (sharing at least four alleles), were statistically overrepresented (OVR STs). The findings indicate that 38% of all clinical mastitis cases and 63% of the PTEs attributed to S. uberis in dairy herds may be caused by the nine most prevalent strains. The findings suggest that a small subset of STs is disproportionally important in the epidemiology of S. uberis mastitis in the United Kingdom, with cow-to-cow transmission of S. uberis potentially occurring in the majority of herds in the United Kingdom, and may be the most important route of infection in many herds. PMID:26491180

  20. Some observations on the epidemiology of bovine leucosis virus infection in a large dairy herd.

    PubMed

    Wilesmith, J W; Straub, O C; Lorenz, R J

    1980-01-01

    Bovine leucosis infection rates were calculated for two years in a naturally infected dairy herd in which serologically positive animals were not preferentially culled. Transmission of infection was found to occur mainly during the winter housing period. No variation in susceptibility to infection with age was found and young animals did not show a prolonged time from infection to sero-conversion. PMID:6246561

  1. Factors associated with frequency of abortions recorded through Dairy Herd Improvement test plans

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Frequency of abortions recorded through Dairy Herd Improvement (DHI) testing was summarized for cows with lactations completed from 2001 through 2009. Reported abortions were 1.3% for 8.5 million DHI lactations of cows with recorded breeding dates and that were >151 d pregnant at lactation terminati...

  2. Management practices associated with presence of Staphylococcus aureus in bulk tank milk from Ohio dairy herds.

    PubMed

    da Costa, L B; Rajala-Schultz, P J; Schuenemann, G M

    2016-02-01

    Staphylococcus aureus is the most common contagious mastitis pathogen affecting cows worldwide. Practices to control this organism have been advocated for decades, and identification of risk factors in individual herds is crucial in prevention and control of Staph. aureus. The objectives of this paper were to estimate prevalence of Staph. aureus in Ohio dairies and to determine a potential association of herd characteristics and management practices with isolation of Staph. aureus in bulk tank milk. A questionnaire about herd characteristics, milking procedures, udder health, mastitis control, and biosecurity practices was mailed to 780 dairy producers; the response rate for the survey was 49%. Staphylococcus aureus prevalence was 48, 64, and 69% when 1, 2, or 3 samples of bulk tank milk from each herd were considered, respectively. Herds practicing prestrip, pre- and postmilking teat dip, and using a single towel per cow as part of the milking routine as well as herds where owners were involved in milking were at significantly reduced odds for detection of Staph. aureus in their bulk tank milk. PMID:26686713

  3. Seroprevalence of Neospora caninum infection on dairy cattle in farms from southern Romania.

    PubMed

    Mitrea, Ioan Liviu; Enachescu, Violeta; Radulescu, Ruxandra; Ionita, Mariana

    2012-02-01

    Neospora caninum, a coccidian parasite closely related to Toxoplasma gondii, is one of the major causes of abortion in cattle worldwide. Conventional serological techniques, such as the indirect fluorescent antibody test and enzyme-linked immunosorbent assay (ELISA), are routinely used in adult animals and aborted fetuses for the detection of anti- N. caninum antibodies. In Romania, infection with N. caninum in cattle has been reported recently, but only in limited areas from the north and central parts of the country. Therefore, the aim of this study was to obtain additional seroepidemiological data on infection with N. caninum on dairy farms from the south of Romania. A total of 258 blood samples was analyzed from 230 dairy cows and 28 calves from 9 dairy farms in southern Romania; the presence of specific IgG antibodies against N. caninum was determined using an indirect ELISA test. The average seroprevalence was 40.3%, but the within-herd prevalence ranged between 11.5 and 80.0%; the seroprevalence in dairy cows was 41.7%, while in calves it was 28.6%. Of the positive samples, 74.0% (77/104) had a high positive reaction (S/P ratio more than 1.0), while 26.0% (27/104) had a low positive reaction (S/P ratio between 0.5 and 1.0). This study indicates that N. caninum infection is widespread in the south of Romania, which could explain the causes of abortions registered in some herds in the studied area. However, a serological screening across the country is planned in order to assess the actual national prevalence of N. caninum infection, followed by implementation of a prevention and control program.

  4. Comparative Evaluation of Different Test Combinations for Diagnosis of Mycobacterium avium Subspecies paratuberculosis Infecting Dairy Herds in India.

    PubMed

    Garg, Rajni; Patil, Prasanna Kumar; Singh, Shoor Vir; Sharma, Shukriti; Gandham, Ravi Kumar; Singh, Ajay Vir; Filia, Gurusimiran; Singh, Pravin Kumar; Jayaraman, Sujata; Gupta, Saurabh; Chaubey, Kundan Kumar; Tiwari, Ruchi; Saminathan, Mani; Dhama, Kuldeep; Sohal, Jagdip Singh

    2015-01-01

    A total of 355 cows were sampled (serum, n = 315; faeces, n = 355; milk, n = 209) from dairy farms located in the Punjab state of India. Faeces and serum/milk samples were screened by acid fast staining and "indigenous ELISA," respectively. IS900 PCR was used to screen faeces and milk samples. Bio-load of MAP in dairy cows was 36.9, 15.6, 16.3, and 14.4%, using microscopy, serum ELISA, milk ELISA and milk PCR, respectively. Estimated kappa values between different test combinations: serum and milk ELISA, faecal microscopy and faecal PCR, milk ELISA and milk PCR, faecal PCR and serum ELISA were 0.325, 0.241, 0.682, and 0.677, respectively. Estimation of the relative sensitivity and specificity of different tests in the present study indicated that "serum ELISA" and "milk ELISA" were good screening tests, add "milk PCR" was "confirmatory test" for MAP infection. Combination of milk ELISA with milk PCR may be adopted as a model strategy for screening and diagnosis of JD in lactating/dairy cattle herds in Indian conditions.

  5. Molecular and serological in-herd prevalence of Anaplasma marginale infection in Texas cattle.

    PubMed

    Hairgrove, Thomas; Schroeder, Megan E; Budke, Christine M; Rodgers, Sandy; Chung, Chungwon; Ueti, Massaro W; Bounpheng, Mangkey A

    2015-04-01

    Bovine anaplasmosis is an infectious, non-contagious disease caused by the rickettsial pathogen Anaplasma marginale (A. marginale). The organism has a global distribution and infects erythrocytes, resulting in anemia, jaundice, fever, abortions and death. Once infected, animals remain carriers for life. The carrier status provides immunity to clinical disease, but is problematic if infected and naïve cattle are comingled. Knowledge of infection prevalence and spatial distribution is important in disease management. The objective of this study was to assess A. marginale infection in-herd prevalence in Texas cattle using both molecular and serological methods. Blood samples from 11 cattle herds within Texas were collected and analyzed by reverse transcription quantitative real-time PCR (RT-qPCR) and a commercial competitive enzyme-linked immunosorbent assay (cELISA). Samples from experimentally infected animals were also analyzed and RT-qPCR detected A. marginale infection up to 15 days before cELISA, providing empirical data to support the interpretation of herd prevalence results. Herds with high prevalence were located in the north Texas Rolling Plains and west Trans-Pecos Desert, with RT-qPCR prevalence as high as 82% and cELISA prevalence as high as 88%. Overall prevalence was significantly higher in cattle in north and west Texas compared to cattle in east Texas (p<0.0001 for prevalence based on both RT-qPCR and cELISA). The overall RT-qPCR and cELISA results exhibited 90% agreement (kappa=0.79) and provide the first A. marginale infection prevalence study for Texas cattle using two diagnostic methods. Since cattle are the most important reservoir host for A. marginale and can serve as a source of infection for tick and mechanical transmission, information on infection prevalence is beneficial in the development of prevention and control strategies.

  6. Molecular and serological in-herd prevalence of Anaplasma marginale infection in Texas cattle.

    PubMed

    Hairgrove, Thomas; Schroeder, Megan E; Budke, Christine M; Rodgers, Sandy; Chung, Chungwon; Ueti, Massaro W; Bounpheng, Mangkey A

    2015-04-01

    Bovine anaplasmosis is an infectious, non-contagious disease caused by the rickettsial pathogen Anaplasma marginale (A. marginale). The organism has a global distribution and infects erythrocytes, resulting in anemia, jaundice, fever, abortions and death. Once infected, animals remain carriers for life. The carrier status provides immunity to clinical disease, but is problematic if infected and naïve cattle are comingled. Knowledge of infection prevalence and spatial distribution is important in disease management. The objective of this study was to assess A. marginale infection in-herd prevalence in Texas cattle using both molecular and serological methods. Blood samples from 11 cattle herds within Texas were collected and analyzed by reverse transcription quantitative real-time PCR (RT-qPCR) and a commercial competitive enzyme-linked immunosorbent assay (cELISA). Samples from experimentally infected animals were also analyzed and RT-qPCR detected A. marginale infection up to 15 days before cELISA, providing empirical data to support the interpretation of herd prevalence results. Herds with high prevalence were located in the north Texas Rolling Plains and west Trans-Pecos Desert, with RT-qPCR prevalence as high as 82% and cELISA prevalence as high as 88%. Overall prevalence was significantly higher in cattle in north and west Texas compared to cattle in east Texas (p<0.0001 for prevalence based on both RT-qPCR and cELISA). The overall RT-qPCR and cELISA results exhibited 90% agreement (kappa=0.79) and provide the first A. marginale infection prevalence study for Texas cattle using two diagnostic methods. Since cattle are the most important reservoir host for A. marginale and can serve as a source of infection for tick and mechanical transmission, information on infection prevalence is beneficial in the development of prevention and control strategies. PMID:25732914

  7. The impact of controlled release capsules of monensin on postcalving haptoglobin concentrations in dairy cattle

    PubMed Central

    2005-01-01

    Abstract This study was designed to assess the impact of a controlled release capsule (CRC) of monensin, administered prior to calving, on postcalving haptoglobin levels. The role of disease on haptoglobin levels was also studied. The study population consisted of 1010 cows from 25 Holstein dairy herds near Guelph, Ontario. Monensin CRC or placebo capsules were randomly assigned within each herd 3 wk prior to the expected calving date. Serum from week 1 and week 6 postcalving was submitted for quantification of haptoglobin concentrations. Haptoglobin results were analyzed for associations with treatment, health data, and individual cow factors up to 95 d in milk. Haptoglobin concentrations were higher in week 1 than week 6 (P < 0.05). In univariate analysis, several diseases were significantly associated with haptoglobin concentrations. However, occurrence of disease appeared to be a confounding factor in the data interpretation. Thus, the analysis was stratified by the presence or absence of disease. There appeared to be associations between factors other than clinical disease contributing to increased haptoglobin levels in both clinically healthy and unhealthy cattle. Haptoglobin served as a good indicator of inflammatory disease. Monensin CRC treatment was associated with increased haptoglobin concentrations in clinically unhealthy cattle, perhaps reflecting a better ability to respond to disease challenge. The lower haptoglobin concentrations in monensin CRC treated cattle that were clinically normal may be a reflection of reduced subclinical disease. PMID:16187551

  8. Evaluation of the epidemiological and economic consequences of control scenarios for bovine viral diarrhea virus in dairy herds.

    PubMed

    Santman-Berends, I M G A; Mars, M H; van Duijn, L; van Schaik, G

    2015-11-01

    Bovine viral diarrhea virus (BVDV) is an important endemic infection. However, no information was available on whether it would be economically beneficial to implement a national control program in the Netherlands. Therefore, a stochastic simulation model was developed in which control scenarios were added to compare the epidemiological and economic consequences of BVDV control in Dutch dairy herds in the next 10 yr. In the epidemiological part of the model, herds could be classified as susceptible, infectious, recovered, or vaccinated. The outputs of the epidemiological module served as input for the economic module. Net costs that could be attributed to bovine viral diarrhea consisted of production losses, costs for testing, and culling persistently infected cattle in the present voluntary Dutch BVDV control program and costs for vaccination. Four different control scenarios were simulated, involving testing and culling of persistently infected (based on serum or ear-notch testing), and monitoring BVDV statuses and vaccination and were derived from BVDV control programs that are currently executed in Europe. The costs and benefits of BVDV control in the current situation and in each of the simulated control scenarios were evaluated assuming an annual discount rate of 2%. The model estimated a mean BVDV herd prevalence of 18.0% in 2014 and showed a slightly decreasing prevalence over time. The outputs seemed realistic for the present situation in the Netherlands when compared with actual survey data. The average annual net costs associated with bovine viral diarrhea were estimated at €27.8 million for the dairy industry. Two control scenarios were beneficial in controlling BVDV during the study period (between 2015 and 2025). In the scenario where tracing and removing of PI animals and monitoring of the subsequent status was obligatory, the benefit to cost (B/C) ratio was 1.5 (€1.5 benefit for each invested euro). In the scenario in which the BVDV status of

  9. Distribution of Leptospira Serogroups in Cattle Herds and Dogs in France

    PubMed Central

    Ayral, Florence C.; Bicout, Dominique J.; Pereira, Helena; Artois, Marc; Kodjo, Angeli

    2014-01-01

    A retrospective study was conducted to identify and describe the distribution pattern of Leptospira serogroups in domestic animals in France. The population consisted of cattle herds and dogs with clinically suspected leptospirosis that were tested at the “Laboratoire des Leptospires” between 2008 and 2011. The laboratory database was queried for records of cattle and dogs in which seroreactivity in Leptospira microagglutination tests was consistent with a recent or current infection, excluding vaccine serogroups in dogs. A total of 394 cattle herds and 232 dogs were diagnosed with clinical leptospirosis, and the results suggested infection by the Leptospira serogroup Australis in 43% and 63%, respectively; by the Leptospira serogroup Grippotyphosa in 17% and 9%, respectively; and by the Leptospira serogroup Sejroe in 33% and 6%, respectively. This inventory of infecting Leptospira serogroups revealed that current vaccines in France are not fully capable of preventing the clinical form of the disease. PMID:25092816

  10. Distribution of Leptospira serogroups in cattle herds and dogs in France.

    PubMed

    Ayral, Florence C; Bicout, Dominique J; Pereira, Helena; Artois, Marc; Kodjo, Angeli

    2014-10-01

    A retrospective study was conducted to identify and describe the distribution pattern of Leptospira serogroups in domestic animals in France. The population consisted of cattle herds and dogs with clinically suspected leptospirosis that were tested at the "Laboratoire des Leptospires" between 2008 and 2011. The laboratory database was queried for records of cattle and dogs in which seroreactivity in Leptospira microagglutination tests was consistent with a recent or current infection, excluding vaccine serogroups in dogs. A total of 394 cattle herds and 232 dogs were diagnosed with clinical leptospirosis, and the results suggested infection by the Leptospira serogroup Australis in 43% and 63%, respectively; by the Leptospira serogroup Grippotyphosa in 17% and 9%, respectively; and by the Leptospira serogroup Sejroe in 33% and 6%, respectively. This inventory of infecting Leptospira serogroups revealed that current vaccines in France are not fully capable of preventing the clinical form of the disease. PMID:25092816

  11. Effect of management on prevention of Salmonella Dublin exposure of calves during a one-year control programme in 84 Danish dairy herds.

    PubMed

    Nielsen, T D; Vesterbæk, I L; Kudahl, A B; Borup, K J; Nielsen, L R

    2012-06-01

    Studies reporting on how to control Salmonella in cattle herds have mainly been theoretical simulation models or case reports describing control of clinical salmonellosis outbreaks. The objective of this observational study was to investigate which management routines were associated with successful control of Salmonella Dublin in calves in dairy herds with previous signs of endemic infection. A total of 86 bulk-tank milk Salmonella Dublin antibody-positive bovine dairy herds were enrolled in the study in September 2008 and were all encouraged to control spread of the infection. One year later it was assessed if they were successful. The criterion for successful control was defined as the 10 youngest calves above three months of age testing Salmonella Dublin antibody-negative, indicating that exposure to Salmonella of these calves from birth until close to the day of testing had been successfully prevented. Management routines were registered through telephone interviews based on a questionnaire resulting in 45 variables for analysis. By the end of the study, a total of 84 herds had completed the interviews and had serum samples collected from calves. Data were analysed using two statistical methods: logistic regression analysis and discriminant analysis. Both analyses identified that increased probability of successful control was strongly associated with avoiding purchase of cattle from test-positive herds. Additionally, ensuring good calving area management, separating calf pens by solid walls rather than bars and not introducing biosecurity routines between the barn sections (e.g. boot wash, change of clothing) were associated with increased probability of successful control in the logistic analysis. The latter may seem illogical, but may be explained by successful herds already having good hygienic routines in place and therefore not having introduced new routines between barn sections in the study period. The discriminant analysis furthermore identified

  12. Bovine viral diarrhoea virus in beef cattle herds of Yucatan, Mexico: seroprevalence and risk factors.

    PubMed

    Solis-Calderon, J J; Segura-Correa, V M; Segura-Correa, J C

    2005-12-12

    A survey of bovine viral diarrhoea virus (BVDV) infection was carried out from June 2001 to July 2002 in a non-vaccinated beef cattle population from the livestock region of Yucatan, Mexico, to assess seroprevalence and identify risk factors related to seroprevalence. The aim was also to estimate the intra-herd correlation (r(e)) and design effect (D) of BVDV seropositivity. Cattle were selected by a two-stage cluster sampling. Blood samples were collected from 560 animals originating from 40 herds. Sera were tested for antibodies against BVDV using an indirect ELISA test. The sensitivity and specificity of the test was 97.9 and 99.7%, respectively. Risk factors regarding the herd and each animal sampled were recorded through a personal interview at the time of blood sampling. Twenty-four of the 40 herds had at least one seropositive animal. The animal true seroprevalence was estimated as 14%. The marginal logistic regression model used to describe the data found a significant (p<0.05) association of herd size-cow-origin interaction. The interaction was due to a higher risk of seropositivity in the category of herds with herds with herd sizes of 101-196 and >196 animals. The r(e) and D values were 0.17+/-0.05 and 3.16+/-0.57, respectively.

  13. Precipitation and temperature effects on mortality and lactation parameters of dairy cattle in California.

    PubMed

    Stull, C L; McV Messam, L L; Collar, C A; Peterson, N G; Castillo, A R; Reed, B A; Andersen, K L; VerBoort, W R

    2008-12-01

    Data from 3 commercial rendering companies located in different regions of California were analyzed from September 2003 through August 2005 to examine the relationship of dairy calf and cow mortality to monthly average daily temperature and total monthly precipitation respectively. Yearly average mortality varied between rendering regions from 2.1 to 8.1% for mature cows. The relationship between cow and calf monthly mortality and monthly average daily temperature was U-shaped. Overall, months with average daily temperatures less than 14 and greater than 24 degrees C showed substantial increases in both calf and cow mortality with calf mortality being more sensitive to changes in these temperature ranges than cow mortality. Temperature changes were reflected in a 2-fold difference between the minimum and maximum mortality in cows and calves. Precipitation showed a weak effect with calf mortality and no effect with cow mortality. Data from Dairy Herd Improvement Association were used from 112 California herds tested over a 24-mo period to examine the relationship of milk production and quality with monthly average daily temperature and monthly precipitation. Somatic cell count and percent milk fat were either weakly or not associated with monthly average daily temperature and total monthly precipitation. However, total monthly precipitation was negatively associated with test day milk per milking cow regardless of the dairy's geographical location. Housing-specific associations for test day milk per milking cow were greater for total monthly precipitation than monthly average daily temperature, with the strongest negative association seen for dairies that do not provide shelter for cows. This suggests that providing suitable housing for lactating dairy cattle may ameliorate the precipitation-associated decrease in test day milk per milking cow. PMID:19038933

  14. Shiga toxin-producing Escherichia coli: pre- and postharvest control measures to ensure safety of dairy cattle products.

    PubMed

    Hussein, Hussein S; Sakuma, Toshie

    2005-01-01

    The large number of cases of human illness caused by Shiga toxin-producing Escherichia coli (STEC) worldwide has raised safety concerns for foods of bovine origin. These human illnesses include diarrhea, hemorrhagic colitis, hemolytic uremic syndrome, and thrombotic thrombocytopenic purpura. Severe cases end with chronic renal failure, chronic nervous system deficiencies, and death. Over 100 STEC serotypes, including E. coli O157:H7, are known to cause these illnesses and to be shed in cattle feces. Thus, cattle are considered reservoirs of these foodborne pathogens. Because beef and dairy products were responsible for a large number of STEC outbreaks, efforts have been devoted to developing and implementing control measures that assure safety of foods derived from dairy cattle. These efforts should reduce consumers' safety concerns and support a competitive dairy industry at the production and processing levels. The efficacy of control measures both before harvest (i.e., on-farm management practices) and after harvest (i.e., milk processing and meat packing) for decreasing the risk of STEC contamination of dairy products was evaluated. The preharvest measures included sanitation during milking and management practices designed to decrease STEC prevalence in the dairy herd (i.e., animal factors, manure handling, drinking water, and both feeds and feeding). The postharvest measures included the practices or treatments that could be implemented during processing of milk, beef, or their products to eliminate or minimize STEC contamination.

  15. Decreased neutrophil function as a cause of retained placenta in dairy cattle.

    PubMed

    Kimura, Kayoko; Goff, Jesse P; Kehrli, Marcus E; Reinhardt, Timothy A

    2002-03-01

    It is unclear why some cows fail to expel the placenta following calving. One theory suggests the fetal placenta must be recognized as "foreign" tissue and rejected by the immune system after parturition to cause expulsion of the placenta. We hypothesized that impaired neutrophil function causes retained placenta (RP). We examined the ability of neutrophils to recognize fetal cotyledon tissue as assessed by a chemotaxis assay, which utilized a placental homogenate obtained from a spontaneously expelled placenta as the chemoattractant. Neutrophil killing ability was also estimated by determining myeloperoxidase activity in isolated neutrophils. Blood samples were obtained from 142 periparturient dairy cattle in two herds. Twenty cattle developed RP (14.1%). Neutrophils isolated from blood of cows with RP had significantly lower neutrophil function in both assays before calving, and this impaired function lasted for 1 to 2 wk after parturition. The addition of antibody directed against interleukin-8 (IL-8) to the cotyledon preparation used as a chemoattractant inhibited chemotaxis by 41%, suggesting that one of the chemoattractants present in the cotyledon at parturition is IL-8. At calving, plasma IL-8 concentration was lower in RP cows (51 +/- 12 pg/ml) than in cows expelling the placenta normally (134 +/- 11 pg/ml). From these data, we suggest that neutrophil function is a determining factor for the development of RP in dairy cattle. Also, depressed production of IL-8 may be a factor affecting neutrophil function in cows developing RP.

  16. Seroprevalence of bovine leukemia virus (BLV) infection in dairy cattle in Isfahan Province, Iran.

    PubMed

    Morovati, Hassan; Shirvani, Edris; Noaman, Vahid; Lotfi, Mohsen; Kamalzadeh, Morteza; Hatami, Alireza; Bahreyari, Masoume; Shahramyar, Zahra; Morovati, Mohammad H; Azimi, Mahmoud; Sakhaei, Davoud

    2012-08-01

    Bovine leukemia virus (BLV), the causative agent of enzootic bovine leukosis (EBL) is an exogenous C-type oncovirus in the Retroviridae family. It causes significant economic losses associated with the costs of control and eradication programs due to carcass condemnation at slaughter and restrictions of export of cattle and semen to importing countries. The main objective of this research was to determine the seroprevalence of BLV infection in cattle herds in central region of Iran (Isfahan province) using a commercial enzyme-linked immunosorbent assay (ELISA) to detect serum antibodies against BLV. Samples of blood serum were collected from 403 female dairy cattle (Holstein-Friesian) from 21 livestock farms and 303 animals (81.9%) were BLV seropositive. A significant association was found between age as a potential risk factor and BVL seroprevalence with animals ≥ 4 years (86.6%) having a significantly (χ(2) = 35.6, p < 0.001) higher seroprevalence compared to those < 4 years (54.2%). We found no significant statistical association between seroprevalence and pregnancy, lactation status and farming systems as potential risk factors in this study (p > 0.1). It is concluded that BLV infection is a very common problem in the study area. Hence, control measures should be instituted to combat the disease and further studies are required to investigate the impact of this disease on dairy production in the country.

  17. Proactive dairy cattle disease control in the UK: veterinary surgeons' involvement and associated characteristics.

    PubMed

    Higgins, H M; Huxley, J N; Wapenaar, W; Green, M J

    2013-09-14

    Characteristics of 94 veterinary surgeons associated with delivering preventive herd-level strategies to control mastitis, lameness and Johne's disease were investigated using two multinomial models. The response variables were 'Gold Standard Monitoring' (including on-going data analysis, risk assessments and laboratory testing), and a lower level of involvement called 'Regular Control Advice'. Although the sample was biased towards those who spend the majority of their time with dairy cows, 69 per cent currently had no involvement in Gold Standard Monitoring for lameness, 60 per cent no involvement with Johne's, and 52 per cent no involvement with mastitis. The final model predicted that an assistant without a postgraduate cattle qualification, who had spent no time on dairy cattle continuous professional development (CPD) in the last year, had an 88 per cent chance of having no involvement with Gold Standard Monitoring for any disease, versus <5 per cent chance for a CPD 'enriched' partner with a postgraduate cattle qualification; there was <1 per cent chance this assistant would be involved with Gold Standard Monitoring of all three diseases on one or more farms, versus a 58 per cent chance for this partner. CPD and employment status were also associated with markedly different probabilities for delivering Regular Control Advice. Increased postgraduate education may further veterinary involvement of this nature.

  18. Drinking water for dairy cattle: always a benefit or a microbiological risk?

    PubMed

    Van Eenige, M J E M; Counotte, G H M; Noordhuizen, J P T M

    2013-02-01

    Drinking water can be considered an essential nutrient for dairy cattle. However, because it comes from different sources, its chemical and microbiological quality does not always reach accepted standards. Moreover, water quality is not routinely assessed on dairy farms. The microecology of drinking water sources and distribution systems is rather complex and still not fully understood. Water quality is adversely affected by the formation of biofilms in distribution systems, which form a persistent reservoir for potentially pathogenic bacteria. Saprophytic microorganisms associated with such biofilms interact with organic and inorganic matter in water, with pathogens, and even with each other. In addition, the presence of biofilms in water distribution systems makes cleaning and disinfection difficult and sometimes impossible. This article describes the complex dynamics of microorganisms in water distribution systems. Water quality is diminished primarily as a result of faecal contamination and rarely as a result of putrefaction in water distribution systems. The design of such systems (with/ without anti-backflow valves and pressure) and the materials used (polyethylene enhances biofilm; stainless steel does not) affect the quality of water they provide. The best option is an open, funnel-shaped galvanized drinking trough, possibly with a pressure system, air inlet, and anti-backflow valves. A poor microbiological quality of drinking water may adversely affect feed intake, and herd health and productivity. In turn, public health may be affected because cattle can become a reservoir of microorganisms hazardous to humans, such as some strains of E. coli, Yersinia enterocolitica, and Campylobacter jejuni. A better understanding of the biological processes in water sources and distribution systems and of the viability of microorganisms in these systems may contribute to better advice on herd health and productivity at a farm level. Certain on-farm risk factors for

  19. Regional environmental simulation of African cattle herding societies

    SciTech Connect

    Krummel, J.R.; Markin, J.B.; O'Neill, R.V.

    1986-03-01

    Regional analyses of the interaction between human populations and natural resources must integrate landscape scale environmental problems. An approach that considers human culture, environmental processes, and resource needs offers an appropriate methodology. With this methodology, we analyze problems of food availability in African cattle-keeping societies. The analysis interrelates cattle biomass, forage availability, milk and blood production, crop yields, gathering, food subsidies, population, and variable precipitation. While an excess of cattle leads to overgrazing, cattle also serve as valuable food storage mechanisms during low rainfall periods. Food subsidies support higher population levels but do not alter drought-induced population fluctuations. Variable precipitation patterns require solutions that stabilize year-to-year food production and also address problems of overpopulation.

  20. Factors associated with clinical mastitis incidence in French dairy herds during late gestation and early lactation.

    PubMed

    Barnouin, J; Chassagne, M

    1998-01-01

    A prospective epidemiological survey was conducted in dairy herds in Brittany (France), concerning 139 herd-years. The data were divided into ten 14 herd-year groups (deciles) and three of these were compared using discrimination by barycentric analysis to study herd late gestation and early lactation variables associated with the annual incidence of herd clinical mastitis in the first 60 days of gestation (CMAI). The first decile included herd-years with low CMAI (o to 4.6%), the second decile, herd-years with medium CMAI (11.6 to 14.3%) and the last decile, herd-years with high CMAI (26.3 to 45.5%). Herd data included diet components, milk yield and reproduction parameters, clinical diseases, body condition score, body dirtiness score and circulating biochemical and hematological markers. The high CMAI group had the following characteristics: 1) lower percentages of dried cows supplemented with vitamins 'ADE'; 2) higher levels of plasma ceruloplasmin and higher gamma glutamyl transferase activities (GGT) in the late gestation period; 3) higher percentages of winter calvings (December, January, February). Clinical mastitis risk could be controlled by supplementations with vitamins A, D and E in the late gestation period, because of the potential relationship between oxidative stress and mastitis. Higher GGT activities would be associated with Fasciolasis via common climatic risk factors (rainfall, humidity) for both mastitis and liver flukes. Winter calving and clinical mastitis would be associated with unfavourable hygiene conditions and stress at calving related to high animal density and bad weather conditions. Ceruloplasmin could be a specific predictor for mastitis risk through nutritional, immune and genetic interrelated factors. PMID:9601148

  1. Dairy goat demography and Q fever infection dynamics

    PubMed Central

    2013-01-01

    Between 2007 and 2009, the largest human Q fever epidemic ever described occurred in the Netherlands. The source was traced back to dairy goat farms, where abortion storms had been observed since 2005. Since one putative cause of these abortion storms is the intensive husbandry systems in which the goats are kept, the objective of this study was to assess whether these could be explained by herd size, reproductive pattern and other demographic aspects of Dutch dairy goat herds alone. We adapted an existing, fully parameterized simulation model for Q fever transmission in French dairy cattle herds to represent the demographics typical for Dutch dairy goat herds. The original model represents the infection dynamics in a herd of 50 dairy cows after introduction of a single infected animal; the adapted model has 770 dairy goats. For a full comparison, herds of 770 cows and 50 goats were also modeled. The effects of herd size and goat versus cattle demographics on the probability of and time to extinction of the infection, environmental bacterial load and abortion rate were studied by simulation. The abortion storms could not be fully explained by demographics alone. Adequate data were lacking at the moment to attribute the difference to characteristics of the pathogen, host, within-herd environment, or a combination thereof. The probability of extinction was higher in goat herds than in cattle herds of the same size. The environmental contamination was highest within cattle herds, which may be taken into account when enlarging cattle farming systems. PMID:23621908

  2. Invited review: Changes in the dairy industry affecting dairy cattle health and welfare.

    PubMed

    Barkema, H W; von Keyserlingk, M A G; Kastelic, J P; Lam, T J G M; Luby, C; Roy, J-P; LeBlanc, S J; Keefe, G P; Kelton, D F

    2015-11-01

    The dairy industry in the developed world has undergone profound changes over recent decades. In this paper, we present an overview of some of the most important recent changes in the dairy industry that affect health and welfare of dairy cows, as well as the science associated with these changes. Additionally, knowledge gaps are identified where research is needed to guide the dairy industry through changes that are occurring now or that we expect will occur in the future. The number of farms has decreased considerably, whereas herd size has increased. As a result, an increasing number of dairy farms depend on hired (nonfamily) labor. Regular professional communication and establishment of farm-specific protocols are essential to minimize human errors and ensure consistency of practices. Average milk production per cow has increased, partly because of improvements in nutrition and management but also because of genetic selection for milk production. Adoption of new technologies (e.g., automated calf feeders, cow activity monitors, and automated milking systems) is accelerating. However, utilization of the data and action lists that these systems generate for health and welfare of livestock is still largely unrealized, and more training of dairy farmers, their employees, and their advisors is necessary. Concurrently, to remain competitive and to preserve their social license to operate, farmers are increasingly required to adopt increased standards for food safety and biosecurity, become less reliant on the use of antimicrobials and hormones, and provide assurances regarding animal welfare. Partly because of increasing herd size but also in response to animal welfare regulations in some countries, the proportion of dairy herds housed in tiestalls has decreased considerably. Although in some countries access to pasture is regulated, in countries that traditionally practiced seasonal grazing, fewer farmers let their dairy cows graze in the summer. The proportion of

  3. Invited review: Changes in the dairy industry affecting dairy cattle health and welfare.

    PubMed

    Barkema, H W; von Keyserlingk, M A G; Kastelic, J P; Lam, T J G M; Luby, C; Roy, J-P; LeBlanc, S J; Keefe, G P; Kelton, D F

    2015-11-01

    The dairy industry in the developed world has undergone profound changes over recent decades. In this paper, we present an overview of some of the most important recent changes in the dairy industry that affect health and welfare of dairy cows, as well as the science associated with these changes. Additionally, knowledge gaps are identified where research is needed to guide the dairy industry through changes that are occurring now or that we expect will occur in the future. The number of farms has decreased considerably, whereas herd size has increased. As a result, an increasing number of dairy farms depend on hired (nonfamily) labor. Regular professional communication and establishment of farm-specific protocols are essential to minimize human errors and ensure consistency of practices. Average milk production per cow has increased, partly because of improvements in nutrition and management but also because of genetic selection for milk production. Adoption of new technologies (e.g., automated calf feeders, cow activity monitors, and automated milking systems) is accelerating. However, utilization of the data and action lists that these systems generate for health and welfare of livestock is still largely unrealized, and more training of dairy farmers, their employees, and their advisors is necessary. Concurrently, to remain competitive and to preserve their social license to operate, farmers are increasingly required to adopt increased standards for food safety and biosecurity, become less reliant on the use of antimicrobials and hormones, and provide assurances regarding animal welfare. Partly because of increasing herd size but also in response to animal welfare regulations in some countries, the proportion of dairy herds housed in tiestalls has decreased considerably. Although in some countries access to pasture is regulated, in countries that traditionally practiced seasonal grazing, fewer farmers let their dairy cows graze in the summer. The proportion of

  4. Herd management and social variables associated with bulk tank somatic cell count in dairy herds in the eastern United States.

    PubMed

    Schewe, R L; Kayitsinga, J; Contreras, G A; Odom, C; Coats, W A; Durst, P; Hovingh, E P; Martinez, R O; Mobley, R; Moore, S; Erskine, R J

    2015-11-01

    The ability to reduce somatic cell counts (SCC) and improve milk quality depends on the effective and consistent application of established mastitis control practices. The US dairy industry continues to rely more on nonfamily labor to perform critical tasks to maintain milk quality. Thus, it is important to understand dairy producer attitudes and beliefs relative to management practices, as well as employee performance, to advance milk quality within the changing structure of the dairy industry. To assess the adoption rate of mastitis control practices in United States dairy herds, as well as assess social variables, including attitudes toward employees relative to mastitis control, a survey was sent to 1,700 dairy farms in Michigan, Pennsylvania, and Florida in January and February of 2013. The survey included questions related to 7 major areas: sociodemographics and farm characteristics, milking proficiency, milking systems, cow environment, infected cow monitoring and treatment, farm labor, and attitudes toward mastitis and related antimicrobial use. The overall response rate was 41% (21% in Florida, 39% in Michigan, and 45% in Pennsylvania). Herd size ranged from 9 to 5,800 cows. Self-reported 3-mo geometric mean bulk tank SCC (BTSCC) for all states was 194,000 cells/mL. Multivariate analysis determined that proven mastitis control practices such as the use of internal teat sealants and blanket dry cow therapy, and not using water during udder preparation before milking, were associated with lower BTSCC. Additionally, farmer and manager beliefs and attitudes, including the perception of mastitis problems and the threshold of concern if BTSCC is above 300,000 cells/mL, were associated with BTSCC. Ensuring strict compliance with milking protocols, giving employees a financial or other penalty if BTSCC increased, and a perceived importance of reducing labor costs were negatively associated with BTSCC in farms with nonfamily employees. These findings highlight the

  5. Herd management and social variables associated with bulk tank somatic cell count in dairy herds in the eastern United States.

    PubMed

    Schewe, R L; Kayitsinga, J; Contreras, G A; Odom, C; Coats, W A; Durst, P; Hovingh, E P; Martinez, R O; Mobley, R; Moore, S; Erskine, R J

    2015-11-01

    The ability to reduce somatic cell counts (SCC) and improve milk quality depends on the effective and consistent application of established mastitis control practices. The US dairy industry continues to rely more on nonfamily labor to perform critical tasks to maintain milk quality. Thus, it is important to understand dairy producer attitudes and beliefs relative to management practices, as well as employee performance, to advance milk quality within the changing structure of the dairy industry. To assess the adoption rate of mastitis control practices in United States dairy herds, as well as assess social variables, including attitudes toward employees relative to mastitis control, a survey was sent to 1,700 dairy farms in Michigan, Pennsylvania, and Florida in January and February of 2013. The survey included questions related to 7 major areas: sociodemographics and farm characteristics, milking proficiency, milking systems, cow environment, infected cow monitoring and treatment, farm labor, and attitudes toward mastitis and related antimicrobial use. The overall response rate was 41% (21% in Florida, 39% in Michigan, and 45% in Pennsylvania). Herd size ranged from 9 to 5,800 cows. Self-reported 3-mo geometric mean bulk tank SCC (BTSCC) for all states was 194,000 cells/mL. Multivariate analysis determined that proven mastitis control practices such as the use of internal teat sealants and blanket dry cow therapy, and not using water during udder preparation before milking, were associated with lower BTSCC. Additionally, farmer and manager beliefs and attitudes, including the perception of mastitis problems and the threshold of concern if BTSCC is above 300,000 cells/mL, were associated with BTSCC. Ensuring strict compliance with milking protocols, giving employees a financial or other penalty if BTSCC increased, and a perceived importance of reducing labor costs were negatively associated with BTSCC in farms with nonfamily employees. These findings highlight the

  6. Systems physiology in dairy cattle: nutritional genomics and beyond.

    PubMed

    Loor, Juan J; Bionaz, Massimo; Drackley, James K

    2013-01-01

    Microarray development changed the way biologists approach the holistic study of cells and tissues. In dairy cattle biosciences, the application of omics technology, from spotted microarrays to next-generation sequencing and proteomics, has grown steadily during the past 10 years. Omics has found application in fields such as dairy cattle nutritional physiology, reproduction, and immunology. Generating biologically meaningful data from omics studies relies on bioinformatics tools. Both are key components of the systems physiology toolbox, which allows study of the interactions between a condition (e.g., nutrition, physiological state) with tissue gene/protein expression and the associated changes in biological functions. The nature of physiologic and metabolic adaptations in dairy cattle at any stage of the life cycle is multifaceted, involves multiple tissues, and is dynamic, e.g., the transition from late-pregnancy to lactation. Application of integrative systems physiology in periparturient dairy cattle has already advanced knowledge of the simultaneous functional adaptations in liver, adipose, and mammary tissue.

  7. Genetic evaluation of mobility for Brown Swiss dairy cattle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Genetic parameters were estimated for mobility score and 16 current linear type traits for Brown Swiss dairy cattle. Mobility is defined as a composite trait measuring the cow’s ability to move as well as the structure of her feet, pasterns, and legs. Scores from 50-99 were assigned by appraisers fo...

  8. A LONGITUDINAL STUDY OF ENTEROCYTOZOON BIENEUSI IN DAIRY CATTLE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Feces from each of 30 Holstein cattle on a Maryland dairy farm were examined at weekly, bimonthly, and then monthly intervals from 1 week to 24 months of age for the presence of Enterocytozoon bienesusi. DNA was extracted from spores cleaned of fecal debris, and a two-step nested PCR protocol was us...

  9. Blood parameters in Swedish dairy herds with high or low incidence of displaced abomasum or ketosis.

    PubMed

    Stengärde, Lena; Holtenius, Kjell; Emanuelson, Ulf; Hultgren, Jan; Niskanen, Rauni; Tråvén, Madeleine

    2011-10-01

    Sixty dairy herds were studied to investigate the association between long-term incidence of displaced abomasum and clinical ketosis and body condition score and blood profiles, including parameters estimating energy metabolism and hepatic lipidosis in the periparturient period and early lactation. Blood samples were taken around parturition and in early lactation from cows without apparent clinical symptoms of metabolic disorders. A difference in metabolism between high and low incidence herds was shown post-partum by a lower metabolic index (the revised Quantitative Insulin Sensitivity Check Index, RQUICKI), and tendencies for higher concentrations of glucose, insulin and non-esterified fatty acids in the high incidence herds. High incidence herds had more cows and produced on average 1400kg energy-corrected milk per cow per year more than the low incidence herds. No differences were found in parameters reflecting liver cell damage. In the first 3weeks post-partum the RQUICKI was a more sensitive marker of herds with a high incidence of displaced abomasum and clinical ketosis than any of the individual parameters, but further research is needed before practical applications of the RQUICKI can be foreseen.

  10. Relationships between age at first calving, herd management criteria and lifetime milk, fat, and protein production in holstein cattle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Data from 69,145 Holstein cows that calved for the first time in 2005 were evaluated to determine the influence of age at first calving (AFC) on first lactation and lifetime production in commercial dairy herds. A DHI database was divided into four herd management criteria (HMC). The four HMC were: ...

  11. Risk factors for cattle presenting with a confirmed bTB lesion at slaughter, from herds with no evidence of within-herd transmission.

    PubMed

    Clegg, T A; Good, M; More, S J

    2016-04-01

    There has been a national bovine tuberculosis (bTB) eradication programme (BTBEP) in Ireland for many years. All cattle herds are tested at least annually using the Single Intradermal Comparative Tuberculin Test (SICTT). Further, abattoir surveillance is conducted on all animals at the time of slaughter. In the Irish BTBEP, a substantial number of confirmed bTB lesions are detected in non-reactor animals, to SICTT, from Officially Tuberculosis Free (OTF) herds at slaughter. In this study we investigate risk factors for non-reactor animals from OTF herds presenting with a confirmed bTB lesion at slaughter, but with no evidence of within-herd transmission. A case-control study was conducted, with animal as the unit of interest. The case animals were all SICTT non-reactor animals slaughtered in 2012, with a confirmed bTB lesion identified during routine abattoir surveillance and with no evidence of within-herd transmission. Control animals were selected from all SICTT non-reactor animals slaughtered in 2012 from OTF herds where no bTB lesion was found. Four controls matched by age (±1 year) and location (county) were randomly selected for each case. A conditional logistic regression model was developed for univariable and multivariable analysis. The final multivariable model included: number of movements, herd type, herd-size, inconclusive reactor status at any previous test, abattoir and time spent in a herd restricted for bTB. The odds of being a case increased with the number of times an animal had moved herds. Animals from suckler herds were significantly more likely to be a case compared to those from beef herds. The odds of being a case decreased with herd-size and increased as the time spent in a restricted herd increased. There were three key conclusions from this study. Firstly, the main risk factors for animals presenting with a confirmed bTB lesion at slaughter were: previous bTB exposure history, previous inconclusive reactor result at the SICTT, the

  12. Assessment of the probability of introducing Mycobacterium tuberculosis into Danish cattle herds.

    PubMed

    Foddai, Alessandro; Nielsen, Liza Rosenbaum; Krogh, Kaspar; Alban, Lis

    2015-11-01

    Tuberculosis is a zoonosis caused by Mycobacterium spp. International trade in cattle is regulated with respect to Mycobacterium bovis (M. bovis) but not Mycobacterium tuberculosis (M. tuberculosis), despite that cattle can become infected with both species. In this study we estimated the annual probability (PIntro) of introducing M. tuberculosis into the Danish cattle population, by the import of cattle and/or by immigrants working in Danish cattle herds. Data from 2013 with date, number, and origin of imported live cattle were obtained from the Danish cattle database. Information on immigrants working in Danish cattle herds was obtained through a questionnaire sent to Danish cattle farmers. The gained inputs were fed into three stochastic scenario trees to assess the PIntro for the current and alternative test-and-manage strategies, such as testing of imported animals and/or testing immigrant workers with the tuberculin skin test. We considered the population of Danish farmers and practitioners free of tuberculosis, because in Denmark, the incidence of the disease in humans is low and primarily related to immigrants and socially disadvantaged people. The median annual probability of introducing M. tuberculosis into the Danish cattle population due to imported live cattle was 0.008% (90% P.I.: 0.0007%; 0.03%), while the probability due to immigrant workers was 4.1% (90% P.I.: 0.8%; 12.1%). The median combined probability (PIntro) due to imported cattle plus workers was 4.1% (90% P.I.: 0.8%; 12.6%). Hence, on average at least one introduction each 24 (90% P.I.: 8; 125) years could be expected. Imported live cattle appeared to play a marginal role on the overall annual PIntro, because they represented only approximately 0.2% of the median annual probability. By testing immigrant workers the overall annual PIntro could be reduced to 0.2% (90% P.I.: 0.04%; 0.7%). Thus, testing of immigrant workers could be considered as a risk mitigation strategy to markedly reduce

  13. Assessment of the probability of introducing Mycobacterium tuberculosis into Danish cattle herds.

    PubMed

    Foddai, Alessandro; Nielsen, Liza Rosenbaum; Krogh, Kaspar; Alban, Lis

    2015-11-01

    Tuberculosis is a zoonosis caused by Mycobacterium spp. International trade in cattle is regulated with respect to Mycobacterium bovis (M. bovis) but not Mycobacterium tuberculosis (M. tuberculosis), despite that cattle can become infected with both species. In this study we estimated the annual probability (PIntro) of introducing M. tuberculosis into the Danish cattle population, by the import of cattle and/or by immigrants working in Danish cattle herds. Data from 2013 with date, number, and origin of imported live cattle were obtained from the Danish cattle database. Information on immigrants working in Danish cattle herds was obtained through a questionnaire sent to Danish cattle farmers. The gained inputs were fed into three stochastic scenario trees to assess the PIntro for the current and alternative test-and-manage strategies, such as testing of imported animals and/or testing immigrant workers with the tuberculin skin test. We considered the population of Danish farmers and practitioners free of tuberculosis, because in Denmark, the incidence of the disease in humans is low and primarily related to immigrants and socially disadvantaged people. The median annual probability of introducing M. tuberculosis into the Danish cattle population due to imported live cattle was 0.008% (90% P.I.: 0.0007%; 0.03%), while the probability due to immigrant workers was 4.1% (90% P.I.: 0.8%; 12.1%). The median combined probability (PIntro) due to imported cattle plus workers was 4.1% (90% P.I.: 0.8%; 12.6%). Hence, on average at least one introduction each 24 (90% P.I.: 8; 125) years could be expected. Imported live cattle appeared to play a marginal role on the overall annual PIntro, because they represented only approximately 0.2% of the median annual probability. By testing immigrant workers the overall annual PIntro could be reduced to 0.2% (90% P.I.: 0.04%; 0.7%). Thus, testing of immigrant workers could be considered as a risk mitigation strategy to markedly reduce

  14. Practical applications of trace minerals for dairy cattle.

    PubMed

    Overton, T R; Yasui, T

    2014-02-01

    Trace minerals have critical roles in the key interrelated systems of immune function, oxidative metabolism, and energy metabolism in ruminants. To date, the primary trace elements of interest in diets for dairy cattle have included Zn, Cu, Mn, and Se although data also support potentially important roles of Cr, Co, and Fe in diets. Trace minerals such as Zn, Cu, Mn, and Se are essential with classically defined roles as components of key antioxidant enzymes and proteins. Available evidence indicates that these trace minerals can modulate aspects of oxidative metabolism and immune function in dairy cattle, particularly during the transition period and early lactation. Chromium has been shown to influence both immune function and energy metabolism of cattle; dairy cows fed Cr during the transition period and early lactation have evidence of improved immune function, increased milk production, and decreased cytological endometritis. Factors that complicate trace mineral nutrition at the farm level include the existence of a large number of antagonisms affecting bioavailability of individual trace minerals and uncertainty in terms of requirements under all physiological and management conditions; therefore, determining the optimum level and source of trace minerals under each specific situation continues to be a challenge. Typical factorial approaches to determine requirements for dairy cattle do not account for nuances in biological function observed with supplementation with various forms and amounts of trace minerals. Trace mineral nutrition modulates production, health, and reproduction in cattle although both formal meta-analysis and informal survey of the literature reveal substantial heterogeneity of response in these outcome variables. The industry has largely moved away from oxide-based programs toward sulfate-based programs; however, some evidence favors shifting supplementation strategies further toward more bioavailable forms of inorganic and organic trace

  15. Simulating the Epidemiological and Economic Impact of Paratuberculosis Control Actions in Dairy Cattle

    PubMed Central

    Kirkeby, Carsten; Græsbøll, Kaare; Nielsen, Søren Saxmose; Christiansen, Lasse E.; Toft, Nils; Rattenborg, Erik; Halasa, Tariq

    2016-01-01

    We describe a new mechanistic bioeconomic model for simulating the spread of Mycobacterium avium subsp. paratuberculosis (MAP) within a dairy cattle herd. The model includes age-dependent susceptibility for infection; age-dependent sensitivity for detection; environmental MAP build up in five separate areas of the farm; in utero infection; infection via colostrum and waste milk, and it allows for realistic culling (i.e., due to other diseases) by including a ranking system. We calibrated the model using a unique dataset from Denmark, including 102 random farms with no control actions against spread of MAP. Likewise, four control actions recommended in the Danish MAP control program were implemented in the model based on reported management strategies in Danish dairy herds in a MAP control scheme. We tested the model parameterization in a sensitivity analysis. We show that a test-and-cull strategy is on average the most cost-effective solution to decrease the prevalence and increase the total net revenue on a farm with low hygiene, but not more profitable than no control strategy on a farm with average hygiene. Although it is possible to eradicate MAP from the farm by implementing all four control actions from the Danish MAP control program, it was not economically attractive since the expenses for the control actions outweigh the benefits. Furthermore, the three most popular control actions against the spread of MAP on the farm were found to be costly and inefficient in lowering the prevalence when used independently. PMID:27777933

  16. Geographical association between the genotype of bovine tuberculosis in found dead badgers and in cattle herds.

    PubMed

    Goodchild, A V; Watkins, G H; Sayers, A R; Jones, J R; Clifton-Hadley, R S

    2012-03-10

    In a survey, 457 badgers that had been found dead in Wales were postmortem-examined, and samples were examined by histology and by extended culture (for up to 12 weeks). Mycobacterium bovis was cultured from 55 badgers (12.0 per cent), and the histology typical of M bovis infection was seen in a further six (1.3 per cent). The prevalence in badgers in each of 10 geographical areas varied between 0 and 26 per cent (P<0.001), and was associated with the incidence of confirmed M bovis infection in cattle herds in the same areas (P<0.01). In northern Wales, bTB was rare in both hosts. An infected badger was 12.3 times more likely to be within 5 km of a confirmed cattle bTB breakdown than an uninfected badger. The M bovis isolates from badgers belonged to one of four genotypes defined by spoligotype and variable number tandem repeat type. These genotypes were also found in 290 concurrent confirmed herd breakdowns, and tended to be similar to the genotypes in badgers in the same geographical areas. When badgers and cattle no more than 30 km apart were compared, the genotype diversity was greater in cattle than in badgers (P=0.016), suggesting that the movement of cattle plays a greater part in the spatial distribution of M bovis than the movement of badgers.

  17. Estimation of the relative impact of treatment and herd management practices on prevention of digital dermatitis in French dairy herds.

    PubMed

    Relun, A; Lehebel, A; Bruggink, M; Bareille, N; Guatteo, R

    2013-07-01

    The purpose of this study was to concurrently estimate the effect of different digital dermatitis (DD) treatment regimens and herd management practices on the occurrence of a new DD lesion. A controlled clinical trial was conducted and involved 4678 dairy cows from 52 French dairy farms where DD was endemic. Farms were allocated by minimisation to one of 4 treatment regimens, varying through the mode (footbath or collective spraying) and the frequency of application (2 days every 4 weeks or fortnightly). They were visited 7 times every 4 weeks by 14 trained investigators. Frailty Cox proportional hazards models were used to estimate the relative effect of potential risk factors and treatment practices on the time until the first occurrence of a DD lesion. At herd level, high initial DD prevalence strongly increased the risk for DD occurrence (HR=1.93, CI 1.23-3.04), as well as absence of hoof-trimming (HR=1.75, CI 1.36-2.27) and poor leg cleanliness (HR=2.44, CI 1.80-3.31). At animal level, Holstein breed (HR=1.92, CI 1.35-3.57) and high-productive cows (HR=1.26, CI 1.01-1.56) were identified to be at higher risk for DD compared to Normande breed and low-productive cows, respectively. Compared to individual topical antibiotic treatments alone, collective treatments tended to decrease the risk of DD occurrence only when applied over 2 days at least every fortnight (HR range=0.64-0.73).

  18. Evaluation of goat based 'indigenous vaccine' against bovine Johne's disease in endemically infected native cattle herds.

    PubMed

    Singh, Shoor Vir; Singh, Pravin Kumar; Kumar, Naveen; Gupta, Saurabh; Chaubey, Kundan Kumar; Singh, Brajesh; Srivastav, Abhishek; Yadav, Sharad; Dhama, Kuldeep

    2015-01-01

    'Indigenous vaccine' prepared from 'Indian Bison Type' a native bio-type of Mycobacterium avium subspecies paratuberculosis strain 'S5' of goat origin (goat based) was evaluated in indigenous cattle herds located in gaushalas (cow shelters), endemic for Bovine Johne's disease. Cows (893) were randomly divided into vaccinated (702 = 626 adults + 76 calves) and control (191 = 173 adults + 18 calves) groups. Response to vaccination was evaluated on the basis of health (mortality, morbidity), productivity (growth rate, reproductive performance, total milk yield), immunological parameters (LTT, ELISA titer), survivability of animals naturally infected with MAP, bacterimia (by specific blood PCR), seroconversion (by indigenous ELISA) and status of shedding of MAP in feces (by microscopy) in the two groups before and after vaccination. Reduction in MAP shedding [to the extent of 100% in Herd A; and from 82.1% (0 DPV) to 10.7% (270 DPV) in Herd C] was the major finding in vaccinated cows. Whereas, the control group cows have shown no improvement. As the first indicator of vaccine efficacy, MAP bacilli disappeared from the blood circulation as early as 15 days post vaccination, however, peak titers were achieved around 90 DPV. Peak titers initially declined slightly but were maintained later throughout the study period. Control animals did not show any pattern in antibody titers. Mortality was low in vaccinated as compared to the control groups. Vaccination of endemically infected native cattle herds with inactivated whole-cell bacterin of novel 'Indian Bison Type' bio-type of goat origin strain 'S5' effectively restored health and productivity and reduced clinical BJD. Application of goat based 'indigenous vaccine' for therapeutic management of BJD in native cattle herds (gaushalas) is the first of its kind. PMID:25675707

  19. Risk factors for foot and mouth disease outbreaks in grazing beef cattle herds.

    PubMed

    Elnekave, E; Zamir, L; Hamd, F; Even Tov, B; Klement, E

    2015-06-15

    Foot and mouth disease (FMD) is considered one of the most important diseases of cattle. Recurrence of FMD outbreaks in Israel is common, even though routine vaccination of livestock is mandatory and control measures are applied during the outbreaks. Grazing beef herds are occasionally involved in these outbreaks and play an important role in disseminating the disease, due to the large efflux of animals from these herds to feedlots. Nevertheless, the risk factors for the occurrence of FMD among these herds have never been investigated. In 2011, Israel faced a large scale outbreak of serotype O FMD virus, which strongly affected beef cattle. We conducted a case-control study of 44 beef cattle herds grazing in the Golan Heights in order to determine the risk factors for FMDV infection. Data were analyzed using a generalized estimation equation (GEE) with a logit link function. Multivariable analysis was conducted for factors with p-value lower than 0.1 in the univariable analysis. The presence of calves under 6 months of age was found as a significant risk factor for FMDV infection in the univariable analysis (odds ratio (OR)=5.95, confidence intervals of 95% (CI95%)=1.59-22.29, p=0.008). This was also the only variable that remained statistically significant in the multivariable analysis. Herds in which more than 6 months between vaccination of adults and exposure had elapsed were in higher risk, albeit not statistically significant, for the occurrence of FMDV infection (OR=3.29, CI95%=0.83-12.99, p=0.089). The higher probability of infection in herds, which included young calves may be a result of their higher susceptibility due to administration of only one or no vaccine prior to the outbreak. The results of the study thus support increasing the frequency of vaccination of both cows and calves in grazing beef herds. Intensifying surveillance where young calves are abundant may also prove efficient for early detection of infected herds and for mitigating outbreaks

  20. Greenhouse gas emissions from the enteric fermentation and manure storage of dairy and beef cattle in China during 1961-2010.

    PubMed

    Gao, Zhiling; Lin, Zhi; Yang, Yuanyuan; Ma, Wenqi; Liao, Wenhua; Li, Jianguo; Cao, Yufeng; Roelcke, Marco

    2014-11-01

    Due to the expanding dairy and beef population in China and their contribution to global CH4 and N2O budgets, a framework considering changes in feed, manure management and herd structure was established to indicate the trends of CH4 and N2O emissions from the enteric formation and manure storage in China׳s beef and dairy production and the underlying driving forces during the period 1961-2010. From 1961 to 2010, annual CH4 and N2O emissions from beef cattle in China increased from 2.18Mt to 5.86Mt and from 7.93kt-29.56kt, respectively, while those from dairy cattle increased from 0.023 to 1.09Mt and 0.12 to 7.90kt, respectively. These increases were attributed to the combined changes in cattle population and management practices in feeds and manure storage. Improvement in cattle genetics during the period increased the bodyweight, required dry matter intake and gross energy and thus resulted in increased enteric CH4 EFs for each category of beef and dairy cattle as well as the overall enteric EFs (i.e., Tier 1 in IPCC). However, for beef cattle, such an impact on the overall enteric EFs was largely offset by the herd structure transition from draft animal-oriented to meat animal-oriented during 1961-2010. Although the CO2-eq of CH4 and N2O from manure storage was less than the enteric emissions during 1961-2010 in China, it tended to increase both in beef and dairy cattle, which was mainly driven by the changes in manure management practices.

  1. Prevalence of Neospora caninum antibodies in dairy cattle and water buffaloes and associated abortions in the plateau of Southern Peninsular India.

    PubMed

    Sengupta, P P; Balumahendiran, M; Raghavendra, A G; Honnappa, T G; Gajendragad, M R; Prabhudas, K

    2013-01-01

    A seroprevalence study of bovine neosporosis was conducted among 1,927 dairy cattle and 341 water buffaloes from Karnataka and Andhra Pradesh states in plateau of southern peninsular India by employing competitive enzyme-linked immunosorbent assay. Overall, 12.61 and 9.97 % sera samples were found positive for the presence of Neospora caninum antibody, respectively, among cattle and water buffaloes. Out of 1,927 sera samples from cattle, 912 and 1,015 samples were collected from unorganized and organized herds, respectively. The cattle screened were of upgraded Holstein-Friesian and water buffaloes were of graded Surti breed. Significantly (p < 0.05) higher prevalence was found in the cattle in unorganized herds (16.66 %) in comparison to organized herds (8.96 %). The highest seroprevalence was recorded in the age group of 4 years and above in both type of cattle herds and water buffaloes. There was a significant variation of seroprevalence (p < 0.05) observed between different age groups of cattle. The rate of seroprevalence increased with the increment in the age of the animals suggesting a possibility of horizontal mode of transmission of the infection from the environment. The percentage of abortion history was more in seropositive group (51.65 %) in comparison to the seronegative group (5.84 %) and the seropositive cattle were 8.84 times more likely to experience abortion than the seronegative cattle. The occurrence of abortion among different age groups varied significantly (p < 0.05). The findings revealed the presence of neosporosis in the southern peninsular India among cattle and water buffaloes and a strong association between the seroprevalence and abortion. PMID:22644733

  2. Prevalence of Neospora caninum antibodies in dairy cattle and water buffaloes and associated abortions in the plateau of Southern Peninsular India.

    PubMed

    Sengupta, P P; Balumahendiran, M; Raghavendra, A G; Honnappa, T G; Gajendragad, M R; Prabhudas, K

    2013-01-01

    A seroprevalence study of bovine neosporosis was conducted among 1,927 dairy cattle and 341 water buffaloes from Karnataka and Andhra Pradesh states in plateau of southern peninsular India by employing competitive enzyme-linked immunosorbent assay. Overall, 12.61 and 9.97 % sera samples were found positive for the presence of Neospora caninum antibody, respectively, among cattle and water buffaloes. Out of 1,927 sera samples from cattle, 912 and 1,015 samples were collected from unorganized and organized herds, respectively. The cattle screened were of upgraded Holstein-Friesian and water buffaloes were of graded Surti breed. Significantly (p < 0.05) higher prevalence was found in the cattle in unorganized herds (16.66 %) in comparison to organized herds (8.96 %). The highest seroprevalence was recorded in the age group of 4 years and above in both type of cattle herds and water buffaloes. There was a significant variation of seroprevalence (p < 0.05) observed between different age groups of cattle. The rate of seroprevalence increased with the increment in the age of the animals suggesting a possibility of horizontal mode of transmission of the infection from the environment. The percentage of abortion history was more in seropositive group (51.65 %) in comparison to the seronegative group (5.84 %) and the seropositive cattle were 8.84 times more likely to experience abortion than the seronegative cattle. The occurrence of abortion among different age groups varied significantly (p < 0.05). The findings revealed the presence of neosporosis in the southern peninsular India among cattle and water buffaloes and a strong association between the seroprevalence and abortion.

  3. Mycobacterium avium Subspecies paratuberculosis and Bovine Leukemia Virus Seroprevalence and Associated Risk Factors in Commercial Dairy and Beef Cattle in Northern and Northeastern China

    PubMed Central

    Sun, Wu-Wen; Lv, Wen-Fa; Cong, Wei; Meng, Qing-Feng; Wang, Chun-Feng; Shan, Xiao-Feng; Qian, Ai-Dong

    2015-01-01

    Mycobacterium avium subspecies paratuberculosis (MAP) and bovine leukemia virus (BLV) are important pathogens, commonly responsible for economical loss to cattle farms all over the world, yet their epidemiology in commercial dairy and beef cattle in China is still unknown. Thus, from September 2013 to December 2014, a large-scale seroprevalence study was conducted to determine the seroprevalence and identify herd-level risk factors associated with MAP and BLV infection. The source sample was 3674 cattle from 113 herds in northern and northeastern China. Antibodies against MAP and BLV were detected using ELISA tests. At animal-level, the seroprevalence of antibodies against MAP and BLV was 11.79% (433/3674) and 18.29% (672/3674), respectively. At herd-level, the seroprevalence of antibodies against MAP and BLV was 20.35% and 21.24% (24/113), respectively. Herd size was identified to be associated with MAP infection while herd size and presence of cattle introduced from other farms were significantly associated with BLV infection. Further research is needed to confirm these findings and improve the knowledge of the epidemiology of these two pathogens in these regions and elsewhere in China. PMID:26504798

  4. Mycobacterium avium Subspecies paratuberculosis and Bovine Leukemia Virus Seroprevalence and Associated Risk Factors in Commercial Dairy and Beef Cattle in Northern and Northeastern China.

    PubMed

    Sun, Wu-Wen; Lv, Wen-Fa; Cong, Wei; Meng, Qing-Feng; Wang, Chun-Feng; Shan, Xiao-Feng; Qian, Ai-Dong

    2015-01-01

    Mycobacterium avium subspecies paratuberculosis (MAP) and bovine leukemia virus (BLV) are important pathogens, commonly responsible for economical loss to cattle farms all over the world, yet their epidemiology in commercial dairy and beef cattle in China is still unknown. Thus, from September 2013 to December 2014, a large-scale seroprevalence study was conducted to determine the seroprevalence and identify herd-level risk factors associated with MAP and BLV infection. The source sample was 3674 cattle from 113 herds in northern and northeastern China. Antibodies against MAP and BLV were detected using ELISA tests. At animal-level, the seroprevalence of antibodies against MAP and BLV was 11.79% (433/3674) and 18.29% (672/3674), respectively. At herd-level, the seroprevalence of antibodies against MAP and BLV was 20.35% and 21.24% (24/113), respectively. Herd size was identified to be associated with MAP infection while herd size and presence of cattle introduced from other farms were significantly associated with BLV infection. Further research is needed to confirm these findings and improve the knowledge of the epidemiology of these two pathogens in these regions and elsewhere in China.

  5. Physical and thermal characteristics of dairy cattle manure.

    PubMed

    Sutitarnnontr, Pakorn; Hu, Enzhu; Tuller, Markus; Jones, Scott B

    2014-11-01

    Greenhouse and regulated gas emissions from animal waste are naturally mediated by moisture content and temperature. As with soils, emissions from manure could be readily estimated given the physical, hydraulic, and thermal properties are described by models and microbes and nutrients are not limiting factors. The objectives of this study were to measure and model physical, hydraulic, and thermal properties of dairy manure to support advanced modeling of gas and water fluxes in addition to solute, colloid, and heat transport. A series of soil science measurement techniques were applied to determine a set of fundamental properties of as-excreted dairy cattle manure. Relationships between manure dielectric permittivity and volumetric water content (θ) were obtained using time-domain reflectometry and capacitance-based dielectric measurements. The measured water retention characteristic for cattle manure was similar to organic peat soil. The unsaturated hydraulic conductivity function of dairy manure was inferred from inverse numerical fitting of laboratory manure evaporation results. The thermal properties of dairy manure, including thermal conductivity, thermal diffusivity, and bulk volumetric heat capacity, were also determined using three penta-needle heat pulse probes. The accuracy of the heat capacity measurements was determined from a comparison of theoretical θ, estimated from the measured thermal properties with that determined by the capacitance-based dielectric measurement. These data represent a novel and unique contribution for advancing prediction and modeling capabilities of gas emissions from cattle manure, although the uncertainties associated with the complexities of shrinkage, surface crust formation, and cracking must also be considered.

  6. Polioencephalomalacia in cattle consuming water with elevated sodium sulfate levels: A herd investigation

    PubMed Central

    Hamlen, Heidi; Clark, Edward; Janzen, Eugene

    1993-01-01

    Polioencephalomalacia (PEM), hereafter used to refer to the specific lesion of cerebrocortical necrosis, developed in 11 of 110 mature cattle on pasture in central Saskatchewan. The primary water source contained a markedly elevated level of sodium sulfate (7200 ppm). The significant clinical findings of the herd investigation included depression, ataxia, cortical blindness, dysphagia, and death. Diagnosis of PEM was confirmed by histopathological evidence of cerebrocortical and subcortical necrosis with microvascular fibrinoid necrosis predominantly in the thalamic region of three affected cattle. The histopathology of sulfate-associated PEM observed in this herd appears to be unique and its features are presented and discussed. Mean levels for serum transketolase, copper, red blood cell transketolase activity, and thiamine (vitamin B1) in all exposed young (n = 100) and mature (n = 99) animals did not reveal evidence of deficiencies. Although the blood thiamine status of the seven surviving, affected animals was not evaluated before treatment with exogenous thiamine, 199 members of the herd had blood thiamine levels within the reference range at the time of the outbreak. The outbreak resolved after cattle were moved to a water source containing acceptable levels of sodium sulfate. ImagesFigure 1. PMID:17424182

  7. Determining the optimum replacement policy for Holstein dairy herds in Iran.

    PubMed

    Kalantari, A S; Mehrabani-Yeganeh, H; Moradi, M; Sanders, A H; De Vries, A

    2010-05-01

    The objective of this study was to determine the optimum replacement policy for Holstein dairy herds in Iran using a dynamic programming model. Cows were described in terms of state variables that included milk production class, parity, pregnancy status, and month in milk with a 1-mo stage length. The objective function maximized the net present value of cows over a 15-yr planning horizon. Markov simulation was used to estimate expected herd dynamics under the optimal decision plan determined by dynamic programming. Stochastic elements included probabilities of pregnancy and abortion, production level, and involuntary culling. The optimum annual culling rate was estimated to be 31.4%, and cows had an expected herd life (time from first calving until culling) of 3.18 yr. High replacement cost and low carcass value resulted in only 2.87% voluntary culling (i.e., optimal model-based replacement). Assuming a heat detection rate of 0.4, cows averaged 2.8 services per lactation under the optimal policy. Sensitivity analyses were carried out to evaluate the effect of milk price, herd-average production, feed cost, heifer price, and carcass value on optimum replacement decisions. Herd-average production, replacement cost, and risk of involuntary culling were important factors affecting the optimal culling policy. Changes in the price of feed, calves, and milk and the probability of pregnancy had no considerable effect on the optimal policy considering the market situation in Iran during 2008.

  8. A HACCP-based approach to mastitis control in dairy herds. Part 1: Development

    PubMed Central

    2011-01-01

    Hazard Analysis and Critical Control Points (HACCP) systems are a risk based preventive approach developed to increase levels of food safety assurance. This is part 1 of a pilot study on the development, implementation and evaluation of a HACCP-based approach for the control of good udder health in dairy cows. The paper describes the use of a novel approach based on a deconstruction of the infectious process in mastitis to identify Critical Control Points (CCPs) and develop a HACCP-based system to prevent and control mastitis in dairy herds. The approach involved the creation of an Infectious Process Flow Diagram, which was then cross-referenced to two production process flow diagrams of the milking process and cow management cycle. The HACCP plan developed, may be suitable for customisation and implementation on dairy farms. This is a logical, systematic approach to the development of a mastitis control programme that could be used as a template for the development of control programmes for other infectious diseases in the dairy herd. PMID:21777489

  9. Review: dairy cattle reproductive physiology research and management--past progress and future prospects.

    PubMed

    Foote, R H

    1996-06-01

    Artificial insemination developed as the solution for two important problems in the dairy cattle industry during the past 50 yr: 1) the need for genetic improvement and 2) the elimination of costly venereal diseases. Cooperation among researchers, extension workers, veterinarians, dairy producers, and emerging AI organizations in pooling their expertise, was instrumental to the remarkably rapid development of AI. The cooperation of universities, government, and producers to fund teams of reproductive specialists to collaborate and transfer findings quickly to potential users was a major component of this successful venture. Money invested in these experiments was estimated to have returned about $100 for each $1 invested. Successful freezing of sperm led to the development of the field of cryobiology, and AI paved the way for embryo transfer. The development of ultrasound equipment; various types of rapid hormone assays; prostaglandins, progestogens, and GnRH; and computerization made possible various alternative management plans for controlling reproduction. Multidisciplinary, multigeographical teams that gather basic needed information have the potential for making excellent progress. As herd size increases, new programs for efficient reproductive management and for identifying needed research through computer modeling are a must. Sexed embryos from elite cows and bulls will be used selectively. When embryonic stem cell technology becomes practical, it will revolutionize cattle breeding. PMID:8827461

  10. Cattle-level risk factors associated with fecal shedding of Shiga toxin-encoding bacteria on dairy farms, Minnesota, USA

    PubMed Central

    Cho, Seongbeom; Fossler, Charles P.; Diez-Gonzalez, Francisco; Wells, Scott J.; Hedberg, Craig W.; Kaneene, John B.; Ruegg, Pamela L.; Warnick, Lorin D.; Bender, Jeffrey B.

    2009-01-01

    The objective of this study was to identify individual cattle-level risk factors associated with fecal shedding of Shiga toxin-encoding bacteria (STB), a surrogate for Shiga toxin-producing E. coli (STEC), on 28 organic and conventional dairy farms. It was found that small organic herds (fewer than 100 cows) were associated with higher odds of Shiga toxin-encoding bacteria (STB) shedding from 2 (all cattle and all cows) of 3 cattle models, followed by small conventional herds, compared with large conventional herds. Preweaned calves [odds ratio (OR) = 2.6, 95% confidence interval (CI): 1.2, 5.7] had higher odds of shedding STB compared with adult cows. Calves more than 28 days of age (OR = 2.0, 95%CI: 1.0, 4.4) were more likely to shed STB than calves less than 28 days of age. This information may be helpful for identifying potential control strategies such as targeted vaccination or management practices. PMID:19436585

  11. Coxiella burnetii seroprevalence and risk for humans on dairy cattle farms, the Netherlands, 2010-2011.

    PubMed

    Schimmer, B; Schotten, N; van Engelen, E; Hautvast, J L A; Schneeberger, P M; van Duijnhoven, Y T H P

    2014-03-01

    Q fever, caused by Coxiella burnetii, is a recognized occupational infection in persons who have regular contact with ruminants. We determined C. burnetii seroprevalence in residents living or working on dairy cattle farms with ≥50 adult cows and identified risk factors for seropositivity. Serum samples from farm residents, including employees, were tested for C. burnetii IgG and IgM; seroprevalence was 72.1% overall and 87.2%, 54.5%, and 44.2% among farmers, spouses, and children, respectively. Risk factors included farm location in southern region, larger herd size, farm employment, birds in stable, contact with pigs, and indirect contact with rats or mice. Protective factors included automatic milking of cows and fully compliant use of gloves during and around calving. We recommend strengthening general biosecurity measures, such as consistent use of personal protective equipment (e.g., boots, clothing, gloves) by farm staff and avoidance of birds and vermin in stables. PMID:24572637

  12. Detection of Mycoplasma canadense and Mycoplasma californicum in dairy cattle from Argentina.

    PubMed

    Tamiozzo, Pablo J; Estanguet, Abel A; Maito, Julia; Tirante, Liliana; Pol, Martin; Giraudo, José A

    2014-01-01

    Different species of Mycoplasma can affect bovine cattle, causing several diseases. PCR sequencing and further analysis of the 16S-23S rRNA ITS region have shown a significant interspecies variability among Mollicutes. Sixteen suspected isolates of Mycoplasma spp. obtained from milk samples from dairy herds were amplified (16S-23S rRNA ITS region). Fourteen out of those 16 suspected Mycoplasma spp. isolates were PCR-positive. To confirm the identity of Mycoplasma bovis, these 14 isolates were tested by another species-specific PCR. Seven of the isolates rendered a positive result. The products of 16S-23S rRNA ITS PCR from one isolate that was identified as M. bovis and from two other isolates, identified as non- M. bovis were randomly selected, sequenced and analyzed. The three sequences (A, B and C) showed 100% similarity with M. bovis, Mycoplasma canadense and Mycoplasma californicum respectively.

  13. Detection of Mycoplasma canadense and Mycoplasma californicum in dairy cattle from Argentina.

    PubMed

    Tamiozzo, Pablo J; Estanguet, Abel A; Maito, Julia; Tirante, Liliana; Pol, Martin; Giraudo, José A

    2014-01-01

    Different species of Mycoplasma can affect bovine cattle, causing several diseases. PCR sequencing and further analysis of the 16S-23S rRNA ITS region have shown a significant interspecies variability among Mollicutes. Sixteen suspected isolates of Mycoplasma spp. obtained from milk samples from dairy herds were amplified (16S-23S rRNA ITS region). Fourteen out of those 16 suspected Mycoplasma spp. isolates were PCR-positive. To confirm the identity of Mycoplasma bovis, these 14 isolates were tested by another species-specific PCR. Seven of the isolates rendered a positive result. The products of 16S-23S rRNA ITS PCR from one isolate that was identified as M. bovis and from two other isolates, identified as non- M. bovis were randomly selected, sequenced and analyzed. The three sequences (A, B and C) showed 100% similarity with M. bovis, Mycoplasma canadense and Mycoplasma californicum respectively. PMID:25011595

  14. Characterization of colostrum from dams of BLV endemic dairy herds.

    PubMed

    Gutiérrez, Gerónimo; Lomonaco, Marina; Alvarez, Irene; Fernandez, Fernando; Trono, Karina

    2015-06-12

    Bovine Leukemia Virus (BLV) is endemic in Argentina, where the individual prevalence is higher than 80% in dairy farms. The aim of this work was to find preliminary evidence to know if the high level of infection of the dam would implicate a higher challenge to her own offspring. We collected 65 sets of samples consisting of dam's blood and colostrum from two heavily infected dairy farms, and investigated the correlation between the dam's blood proviral load and the presence of provirus in colostrum. We also described the dual antibody/provirus profile in the colostrum. Provirus was detected in 69.23% of the colostrum samples, mostly from dams with a high proviral load, 36/45 (80%). Colostrum proviral load was significantly higher in dams with high blood proviral load (p<0.0001). Provirus was detected in colostrum samples all along the antibody distribution, even in those with a low amount of antibodies. These results show that even when high blood proviral load dams offer higher levels of infected cells to their offspring through colostrum they also offer higher levels of protection of antibodies. On the contrary, low blood proviral load dams also offer infected cells but a poor content of antibodies, suggesting that these animals could play an important role in the epidemiological cycle of transmission.

  15. Characterization of colostrum from dams of BLV endemic dairy herds.

    PubMed

    Gutiérrez, Gerónimo; Lomonaco, Marina; Alvarez, Irene; Fernandez, Fernando; Trono, Karina

    2015-06-12

    Bovine Leukemia Virus (BLV) is endemic in Argentina, where the individual prevalence is higher than 80% in dairy farms. The aim of this work was to find preliminary evidence to know if the high level of infection of the dam would implicate a higher challenge to her own offspring. We collected 65 sets of samples consisting of dam's blood and colostrum from two heavily infected dairy farms, and investigated the correlation between the dam's blood proviral load and the presence of provirus in colostrum. We also described the dual antibody/provirus profile in the colostrum. Provirus was detected in 69.23% of the colostrum samples, mostly from dams with a high proviral load, 36/45 (80%). Colostrum proviral load was significantly higher in dams with high blood proviral load (p<0.0001). Provirus was detected in colostrum samples all along the antibody distribution, even in those with a low amount of antibodies. These results show that even when high blood proviral load dams offer higher levels of infected cells to their offspring through colostrum they also offer higher levels of protection of antibodies. On the contrary, low blood proviral load dams also offer infected cells but a poor content of antibodies, suggesting that these animals could play an important role in the epidemiological cycle of transmission. PMID:25829243

  16. Ingestion and mastication of feed by dairy cattle.

    PubMed

    Beauchemin, K A

    1991-07-01

    For fiber in dairy cattle diets to be effective it must be masticated initially during feeding and again during rumination. Time spent chewing is directly related to saliva secretion, which helps buffer the rumen environment and optimizes fiber digestion. Reduction in feed particle size occurs during chewing, which is a prerequisite for passage of feeds from the forestomach, but the extent of particle breakdown during chewing depends upon the feed. Manipulating the dietary concentration of plant cell walls or the physical form of forage can alter chewing behavior and rumen function of the dairy cow, thereby optimizing productivity.

  17. Epidemiologic study on Besnoitia besnoiti infection in dairy herds in Jordan.

    PubMed

    Talafha, Abdelsalam Q; Al-Majali, Ahmad M; Ababneh, Mohammad M; Abutarbush, Sameeh M

    2015-07-01

    Besnoitia besnoiti is an apicomplexan parasite and the causative agent of bovine besnoitiosis which is considered as a re-emergent disease in Europe. A cross-sectional serological study was conducted to determine the seroprevalence and to identify risk factors associated with B. besnoiti infection in 68 dairy herds (n = 806 cows) in Jordan during the period from January to June 2007 and the spring of 2014. Data regarding herd's management was obtained by filling questionnaires through personal interviews with farmers. An indirect ELISA test was used to detect antibodies against B. besnoiti. Chi-square analysis and multivariable logistic regression model were used to identify risk factors associated with seropositivity to B. besnoiti. At the individual cow and herd level, the true prevalence of seropositive animals was 6 and 28.7 %, respectively. Cows between 2 and 6 years of age had significantly higher seroprevalence of B. besnoiti than other age groups. The highest seroprevalence of B. besnoiti was found in Zarqa and Irbid governorates. Multivariable logistic regression model identified that exchanging visits by farm workers to neighboring farms as a risk factor for seropositivity to B. besnoiti, while smaller herd size and twice a day farm cleaning using sweeping and water hosing were identified as protective factors. This is the first study that investigated the seroprevalence of B. besnoiti infection in dairy herds in Jordan. Further studies are warranted to explore the clinical manifestation of B. besnoiti infection as well as to identify the possible presence of other Besnoitia species and definitive hosts for the parasite.

  18. An evaluation of parameters for the detection of subclinical rumen acidosis in dairy herds.

    PubMed

    Enemark, J M D; Jørgensen, R J; Kristensen, N B

    2004-11-01

    An observational study was conducted in six Danish dairy herds. A specially designed stomach tube was compared to the rumenocentesis technique as part of the monitoring of rumen pH. In contrast to a previous study, the use of the stomach tube appeared to reduce saliva contamination. However, correlation with the rumenocentesis technique was poor ( r = 0.33; p = 0.019) and a linear model could only partly explain variations between either results. The presence of subclinical rumen acidosis (SRA) was evidenced in one herd only, as judged by results obtained by the rumenocentesis technique. The present study revealed some limitations of the rumenocentesis technique in small or medium-sized herds due to difficulties in selecting sufficient numbers of cows in the respective groups at risk. The finding of two apparently clinical normal cows with rumen pH values below 5.0 leads to the consideration that such fluctuations may be temporary and at least does not give rise to clinical symptoms. However, the long-term effect of such fluctuations is not known. In general, primiparous cows seemed more prone to low ruminal pH values (< 6.0), higher ruminal concentrations of short-chain fatty acids, and possibly to metabolic acidosis, than were multiparous cows. Ruminal propionate was the most precise predictor of rumen pH, whereas milk fat percentage varied greatly between lactational groups. Blood lactate dehydrogenase (LDH), beta-hydroxybutyrate (BHB) and fructosamine as well as urine phosphorus excretion and renal net acid-base excretion (NABE) were related to ruminal acid load, but were not predictive of rumen pH. Monitoring of dairy herds for SRA should be performed routinely and employ several diagnostic tools (rumenocentesis, renal NABE determination) as well as specific knowledge of herd management and feeding routines.

  19. Fraction of bovine leukemia virus-infected dairy cattle developing enzootic bovine leukosis.

    PubMed

    Tsutsui, Toshiyuki; Kobayashi, Sota; Hayama, Yoko; Yamamoto, Takehisa

    2016-02-01

    Enzootic bovine leucosis (EBL) is a transmissible disease caused by the bovine leukemia virus that is prevalent in cattle herds in many countries. Only a small fraction of infected animals develops clinical symptoms, such as malignant lymphosarcoma, after a long incubation period. In the present study, we aimed to determine the fraction of EBL-infected dairy cattle that develop lymphosarcoma and the length of the incubation period before clinical symptoms emerge. These parameters were determined by a mathematical modeling approach based on the maximum-likelihood estimation method, using the results of a nationwide serological survey of prevalence in cattle and passive surveillance records. The best-fit distribution to estimate the disease incubation period was determined to be the Weibull distribution, with a median and average incubation period of 7.0 years. The fraction of infected animals developing clinical disease was estimated to be 1.4% with a 95% confidence interval of 1.2-1.6%. The parameters estimated here contribute to an examination of efficient control strategies making quantitative evaluation available. PMID:26754928

  20. Fraction of bovine leukemia virus-infected dairy cattle developing enzootic bovine leukosis.

    PubMed

    Tsutsui, Toshiyuki; Kobayashi, Sota; Hayama, Yoko; Yamamoto, Takehisa

    2016-02-01

    Enzootic bovine leucosis (EBL) is a transmissible disease caused by the bovine leukemia virus that is prevalent in cattle herds in many countries. Only a small fraction of infected animals develops clinical symptoms, such as malignant lymphosarcoma, after a long incubation period. In the present study, we aimed to determine the fraction of EBL-infected dairy cattle that develop lymphosarcoma and the length of the incubation period before clinical symptoms emerge. These parameters were determined by a mathematical modeling approach based on the maximum-likelihood estimation method, using the results of a nationwide serological survey of prevalence in cattle and passive surveillance records. The best-fit distribution to estimate the disease incubation period was determined to be the Weibull distribution, with a median and average incubation period of 7.0 years. The fraction of infected animals developing clinical disease was estimated to be 1.4% with a 95% confidence interval of 1.2-1.6%. The parameters estimated here contribute to an examination of efficient control strategies making quantitative evaluation available.

  1. Anaerobic digestion of dairy cattle manure autoheated by aerobic pretreatment

    SciTech Connect

    Achkari-Begdouri, A.

    1989-01-01

    A novel way to heat anaerobic digesters was investigated. Dairy cattle manure was autoheated by an aerobic pretreatment process and then fed to the anaerobic digester. Important physical properties of the dairy cattle manure were determined. These included bulk density, specific heat, thermal conductivity and the rheological properties; consistency coefficient, behavior index and apparent viscosity. These parameters were used to calculate the overall heat transfer coefficients, and to estimate the heat losses from the aerobic reactor to the outside environment. The total energy balance of the aerobic treatment system was then established. An optimization study of the main parameters influencing the autoheating process showed that the total solids, the air flow rate and the stirring speed for operation of the aerobic pretreatment should be approximately 7%, 70 L/H and 1,400 rpm respectively. Temperatures as high as 65C were reached in 40 hours of aerobic treatment. At the above recommended levels of total solids, the air flow rate and the stirring speed, there was little difference in the energy requirements for heating the influent by aeration and heating the influent by a conventional heating system. In addition to the temperature increase, the aerobic pretreatment assisted in balancing the anaerobic digestion process and increased the methanogenesis of the dairy cattle manure. Despite the 8% decomposition of organic matter that occurred during the aerobic pretreatment process, methane production of the digester started with the aerobically heated manure was significantly higher (at least 20% higher) than of the digester started with conventionally heated manure. The aerobic system successfully autoheated the dairy cattle manure with an energy cost equal to that of conventionally heated influent.

  2. [Tongue play and manganese deficiency in dairy cattle].

    PubMed

    Karatzias, H; Roubies, N; Polizopoulou, Z; Papasteriades, A

    1995-09-01

    The present paper discusses "tongue rolling" observed in dairy cattle farms of a region in northern Greece associated with manganese deficiency. In these animals total body manganese status was evaluated by determining hair, as well as feed manganese content. Cows exhibiting tongue rolling had significantly lower hair manganese content, compared to non-tongue rolling control animals from other farms; in addition, feedstuff analysis demonstrated that manganese and inorganic phosphorus intake of affected cows was also significantly lower.

  3. Effect of aggregation of horn fly populations within cattle herds and consequences for sampling to obtain unbiased estimates of abundance.

    PubMed

    Lysyk, T J; Steelman, C D

    2004-07-01

    Reanalysis of counts of horn fly, Hematobia irritans (L.), obtained from a variety of cattle herds indicated that aggregation of the flies within herds decreased as mean fly density increased. Aggregation was also related to the proportion of fly-resistant and fly-susceptible cattle in a herd. Herds were grouped according to their degree of horn fly aggregation. Low aggregation herds included larger framed Angus, Horned Hereford, Polled Hereford, and Red Poll breeds. Moderate aggregation occurred with Brahman, Charolais, small-framed Angus, mixed cows, and Hereford x Charolais cross. High aggregation occurred with Chianina and mixed herds. Relationships between the sample means and variances varied among aggregation groups. A resampling approach was used to determine the influence of random sampling of a herd on the proportion of horn fly population estimates within fixed percentages of the true mean. The proportion of sample means within +/- 5, 10, 15, and 20% of the true means varied with the proportion of the herd sampled, the mean and variance of fly density, and herd size. Recommendations for obtaining sample size to estimate fly density within a fixed percentage of the true mean are given.

  4. Effect of aggregation of horn fly populations within cattle herds and consequences for sampling to obtain unbiased estimates of abundance.

    PubMed

    Lysyk, T J; Steelman, C D

    2004-07-01

    Reanalysis of counts of horn fly, Hematobia irritans (L.), obtained from a variety of cattle herds indicated that aggregation of the flies within herds decreased as mean fly density increased. Aggregation was also related to the proportion of fly-resistant and fly-susceptible cattle in a herd. Herds were grouped according to their degree of horn fly aggregation. Low aggregation herds included larger framed Angus, Horned Hereford, Polled Hereford, and Red Poll breeds. Moderate aggregation occurred with Brahman, Charolais, small-framed Angus, mixed cows, and Hereford x Charolais cross. High aggregation occurred with Chianina and mixed herds. Relationships between the sample means and variances varied among aggregation groups. A resampling approach was used to determine the influence of random sampling of a herd on the proportion of horn fly population estimates within fixed percentages of the true mean. The proportion of sample means within +/- 5, 10, 15, and 20% of the true means varied with the proportion of the herd sampled, the mean and variance of fly density, and herd size. Recommendations for obtaining sample size to estimate fly density within a fixed percentage of the true mean are given. PMID:15311450

  5. Tuberculosis transmission by Mycobacterium bovis in a mixed cattle and goat herd.

    PubMed

    Zanardi, Giorgio; Boniotti, Maria Beatrice; Gaffuri, Alessandra; Casto, Barbara; Zanoni, Mariagrazia; Pacciarini, Maria Lodovica

    2013-10-01

    A tuberculosis (TB) outbreak caused by Mycobacterium bovis occurred in a mixed herd of three cattle and eighteen goats in Northern Italy in 2005. All the cattle were removed, as opposed to the co-existing goats, who remained in the farm and were not subsequently tested by the official intradermal tuberculin test. At the beginning of May 2006, a 7-day old calf was introduced into the herd from an officially TB-free (OTF) farm. On October 2006, tuberculous lesions were detected at the slaughterhouse in the same animal. The following epidemiological investigation on the herd highlighted a clinical suspicion of TB in one goat out of 35, and visible lesions were found at necropsy in the respiratory and intestinal tracts. Bacteriological culture and molecular tests confirmed the presence of M. bovis in both animals. Spoligotyping and Mycobacterial Interspersed Repetitive Units - Variable Number of Tandem Repeats (MIRU-VNTR) showed the same genomic profile of the previous breakdown occurred in 2005. Since this profile has never been described in Italy, these findings suggest the probable transmission of TB within the farm among cattle and goats. The remaining 34 goats were also tested by single intradermal cervical comparative tuberculin (SICCT) test, Interferon (IFN)-γ assay and ELISA for antibody to M. bovis. The SICCT test and the IFN-γ showed a good concordance with 20 and 19 positive reactors, respectively. By ELISA we found 12Ab-positive animals, seven of which had not been detected by the tests for cell-mediated immunity. Finally, 15 goats were found positive for gross lesions at necropsy. The in vivo tests revealed a total of 27 positive animals out of 35, which highlights the usefulness of the serology in parallel with SICCT and IFN-γ when an advanced stage of infection is suspected. Moreover, our results confirm the necessity for adopting the official tuberculin test on goats co-existing with cattle.

  6. Prevalence of shiga toxin-producing Escherichia coli in dairy cattle and their products.

    PubMed

    Hussein, H S; Sakuma, T

    2005-02-01

    The main objective of this review was to assess the role of dairy cattle and their products in human infections with Shiga toxin-producing Escherichia coli (STEC). A large number of STEC strains (e.g., members of the serogroups O26, O91, O103, O111, O118, O145, and O166) have caused major outbreaks and sporadic cases of human illnesses that have ranged from mild diarrhea to the life-threatening hemolytic uremic syndrome. These illnesses were traced to O157 and non-O157 STEC. In most cases, STEC infection was attributed to consumption of ground beef or dairy products that were contaminated with cattle feces. Thus, dairy cattle are considered reservoirs of STEC and can impose a significant health risk to humans. The global nature of food supply suggests that safety concerns with beef and dairy foods will continue and the challenges facing the dairy industry will increase at the production and processing levels. In this review, published reports on STEC in dairy cattle and their products were evaluated to achieve the following specific objectives: 1) to assemble a database on human infections with STEC from dairy cattle, 2) to assess prevalence of STEC in dairy cattle, and 3) to determine the health risks associated with STEC strains from dairy cattle. The latter objective is critically important, as many dairy STEC isolates are known to be of high virulence. Fecal testing of dairy cattle worldwide showed wide ranges of prevalence rates for O157 (0.2 to 48.8%) and non-O157 STEC (0.4 to 74.0%). Of the 193 STEC serotypes of dairy cattle origin, 24 have been isolated from patients with hemolytic uremic syndrome. Such risks emphasize the importance and the need to develop long-term strategies to assure safety of foods from dairy cattle.

  7. Greenhouse gas emissions from the enteric fermentation and manure storage of dairy and beef cattle in China during 1961–2010

    SciTech Connect

    Gao, Zhiling; Lin, Zhi; Yang, Yuanyuan; Ma, Wenqi; Liao, Wenhua; Li, Jianguo; Cao, Yufeng; Roelcke, Marco

    2014-11-15

    Due to the expanding dairy and beef population in China and their contribution to global CH{sub 4} and N{sub 2}O budgets, a framework considering changes in feed, manure management and herd structure was established to indicate the trends of CH{sub 4} and N{sub 2}O emissions from the enteric formation and manure storage in China's beef and dairy production and the underlying driving forces during the period 1961–2010. From 1961 to 2010, annual CH{sub 4} and N{sub 2}O emissions from beef cattle in China increased from 2.18 Mt to 5.86 Mt and from 7.93 kt–29.56 kt, respectively, while those from dairy cattle increased from 0.023 to 1.09 Mt and 0.12 to 7.90 kt, respectively. These increases were attributed to the combined changes in cattle population and management practices in feeds and manure storage. Improvement in cattle genetics during the period increased the bodyweight, required dry matter intake and gross energy and thus resulted in increased enteric CH{sub 4} EFs for each category of beef and dairy cattle as well as the overall enteric EFs (i.e., Tier 1 in IPCC). However, for beef cattle, such an impact on the overall enteric EFs was largely offset by the herd structure transition from draft animal-oriented to meat animal-oriented during 1961–2010. Although the CO{sub 2}-eq of CH{sub 4} and N{sub 2}O from manure storage was less than the enteric emissions during 1961–2010 in China, it tended to increase both in beef and dairy cattle, which was mainly driven by the changes in manure management practices. - Highlights: • CH{sub 4} emissions dominated the CO{sub 2}-eq emissions from dairy and beef cattle in China. • Beef herd transition played an important role in CH{sub 4} emissions. • Changes of manure managements increased the manure EFs of CH{sub 4} and N{sub 2}O. • Manure contributed very less to the total CO{sub 2}-eq emissions but tended to grow.

  8. Arsenic poisoning in dairy cattle from naturally occurring arsenic pyrites.

    PubMed

    Hopkirk, R G

    1987-10-01

    An outbreak of arsenic poisoning occurred in which most of a 200 cow dairy herd were affected and six died. The source of the arsenic was naturally occurring arsenic pyrites from the Waiotapu Stream, near Rotorua. Arsenic levels in the nearby soil were as high as 6618 ppm. There was little evidence to suggest that treatment affected the course of the disease. Haematology was of little use in diagnosis, post-mortem signs were not always consistent and persistence of the element in the liver appeared short. Control of further outbreaks have been based on practical measures to minimise the intake of contaminated soil and free laying water by the stock. PMID:16031332

  9. Arsenic poisoning in dairy cattle from naturally occurring arsenic pyrites.

    PubMed

    Hopkirk, R G

    1987-10-01

    An outbreak of arsenic poisoning occurred in which most of a 200 cow dairy herd were affected and six died. The source of the arsenic was naturally occurring arsenic pyrites from the Waiotapu Stream, near Rotorua. Arsenic levels in the nearby soil were as high as 6618 ppm. There was little evidence to suggest that treatment affected the course of the disease. Haematology was of little use in diagnosis, post-mortem signs were not always consistent and persistence of the element in the liver appeared short. Control of further outbreaks have been based on practical measures to minimise the intake of contaminated soil and free laying water by the stock.

  10. Genomic selection for tolerance to heat stress in Australian dairy cattle.

    PubMed

    Nguyen, Thuy T T; Bowman, Phil J; Haile-Mariam, Mekonnen; Pryce, Jennie E; Hayes, Benjamin J

    2016-04-01

    Temperature and humidity levels above a certain threshold decrease milk production in dairy cattle, and genetic variation is associated with the amount of lost production. To enable selection for improved heat tolerance, the aim of this study was to develop genomic estimated breeding values (GEBV) for heat tolerance in dairy cattle. Heat tolerance was defined as the rate of decline in production under heat stress. We combined herd test-day recording data from 366,835 Holstein and 76,852 Jersey cows with daily temperature and humidity measurements from weather stations closest to the tested herds for test days between 2003 and 2013. We used daily mean values of temperature-humidity index averaged for the day of test and the 4 previous days as the measure of heat stress. Tolerance to heat stress was estimated for each cow using a random regression model with a common threshold of temperature-humidity index=60 for all cows. The slope solutions for cows from this model were used to define the daughter trait deviations of their sires. Genomic best linear unbiased prediction was used to calculate GEBV for heat tolerance for milk, fat, and protein yield. Two reference populations were used, the first consisted of genotyped sires only (2,300 Holstein and 575 Jersey sires), and the other included genotyped sires and cows (2,189 Holstein and 1,188 Jersey cows). The remainder of the genotyped sires were used as a validation set. All animals had genotypes for 632,003 single nucleotide polymorphisms. When using only genotyped sires in the reference set and only the first parity data, the accuracy of GEBV for heat tolerance in relation to changes in milk, fat, and protein yield were 0.48, 0.50, and 0.49 in the Holstein validation sires and 0.44, 0.61, and 0.53 in the Jersey validation sires, respectively. Some slight improvement in the accuracy of prediction was achieved when cows were included in the reference population for Holsteins. No clear improvements in the accuracy of

  11. Severe Mycoplasma bovis outbreak in an Austrian dairy herd.

    PubMed

    Pothmann, Harald; Spergser, Joachim; Elmer, Josef; Prunner, Isabella; Iwersen, Michael; Klein-Jöbstl, Daniela; Drillich, Marc

    2015-11-01

    A conventional dairy farm, housing 19 Austrian Simmental cows, experienced a spontaneous outbreak of a Mycoplasma bovis infection, showing severe clinical signs of respiratory tract disease, clinical mastitis, and tremendous drop in milk production. Despite intensive therapy, 5 cows died within 2 weeks or were euthanized. From the remaining cows, bacteriological culture and polymerase chain reaction revealed M. bovis in 10 of 14 milk samples. Mycoplasma bovis was found in 1 of 5 randomly collected nasal swabs. Autopsy of 1 cow revealed infection of the lungs and the udder with M. bovis. The 13 M. bovis isolates from milk samples, nasal swabs, lungs, and udder were genotyped by multilocus variable number of tandem-repeat analysis, and indicated that described infections were caused by a single M. bovis strain. The virulent M. bovis strain resulted in dramatic economic loss to the farmer. To control the disease, culling of all animals, including heifers and calves, was recommended, and strict hygienic measures were implemented before introducing new animals to the farm. PMID:26450838

  12. Prevalence and herd-level risk factors for intramammary infection with coagulase-negative staphylococci in Dutch dairy herds.

    PubMed

    Sampimon, O C; Barkema, H W; Berends, I M G A; Sol, J; Lam, T J G M

    2009-02-16

    In this study, the prevalence of intramammary infection (IMI) with coagulase-negative staphylococci (CNS) in The Netherlands was estimated on 49 randomly selected herds with at least 40 lactating cows. In total, 4220 quarter milk samples were collected. The prevalence of CNS IMI in The Netherlands was estimated at 10.8% at quarter level and 34.4% at cow level, making it the most frequently isolated group of pathogens. Fourteen species of CNS were identified; the most frequently isolated species was Staphylococcus chromogenes (30.3%) followed by Staphylococcus epidermidis (12.9%) and Staphylococcus capitis (11.0%). Prevalence of CNS IMI was higher in heifers compared to older cows. Geometric mean quarter SCC of CNS-positive quarters was 109,000 cells/ml, which was approximately twice as high as culture-negative quarters. Quarters infected with S. chromogenes, S. capitis and Staphylococcus xylosus had a higher SCC (P<0.05) than culture-negative quarters, while quarters that were culture-positive for S. epidermidis and Staphylococcus hyicus tended to have a higher SCC than culture-negative quarters. An increased prevalence of CNS IMI was associated with the herd-level variables source of drinking water not being tap water, housing of dry cows in one group instead of multiple groups, measurement of cow SCC every month, udder health monitoring by the veterinarian, pasturing during outdoor season, percentage of stalls contaminated with milk, and BMSCC>250,000 cells/ml. Although a causal relation between these factors and prevalence of CNS is not proven and for some factors not even likely, knowledge of the associations found may be helpful when approaching CNS problems on dairy farms. PMID:18977613

  13. Bovine Viral Diarrhoea Virus (BVDV) in Dairy Cattle: A Matched Case-Control Study.

    PubMed

    Machado, G; Egocheaga, R M F; Hein, H E; Miranda, I C S; Neto, W S; Almeida, L L; Canal, C W; Stein, M C; Corbellini, L G

    2016-02-01

    Bovine viral diarrhoea virus (BVDV) causes one of the most important diseases of cattle in terms of economic costs and welfare. The aims were to estimate herd prevalence and to investigate the factors associated with antibodies in bulk tank milk (BTM) in dairy herds through a matched case-control study. To estimate herd prevalence, BTM samples were randomly selected (n = 314) from a population (N = 1604). The true prevalence of BVDV was 24.3% (CI 95% = 20.1-29.3%). For the case-control study, BVDV antibody-positive herds (high antibody titres) were classified as cases (n = 21) and matched (n = 63) by milk production with herds presenting low antibody titres (ratio of 1 : 3). Three multivariable models were built: 1) full model, holding all 21 variables, and two models divided according to empirical knowledge and similarity among variables; 2) animal factor model; and 3) biosecurity model. The full model (model 1) identified: age as a culling criteria (OR = 0.10; CI 95% = 0.02-0.39; P < 0.01); farms that provided milk to other industries previously (OR = 4.13; CI 95% = 1.17-14.49; P = 0.02); and isolation paddocks for ill animals (OR = 0.14; CI 95% = 0.01-0.26; P = 0.02). The biosecurity model revealed a significant association with the use of natural mating (OR = 9.03; CI 95% = 2.14-38.03; P < 0.01); isolation paddocks for ill animals (OR = 0.06; CI 95% = 0.05-0.83; P = 0.03); years providing milk for the same industry (OR = 0.94; CI 95% = 0.91-0.97; P = 0.02); and direct contact over fences among cattle of neighbouring farms (OR = 5.78; CI 95% = 1.41-23.67; P = 0.04). We recommend the application of grouping predictors as a good choice for model building because it could lead to a better understanding of disease-exposure associations.

  14. Herd-level risk factors for Campylobacter fetus infection, Brucella seropositivity and within-herd seroprevalence of brucellosis in cattle in northern Nigeria.

    PubMed

    Mai, H M; Irons, P C; Kabir, J; Thompson, P N

    2013-09-01

    Brucellosis and campylobacteriosis are economically important diseases affecting bovine reproductive efficiency in Nigeria. A questionnaire-based survey was conducted in 271 cattle herds in Adamawa, Kaduna and Kano states of northern Nigeria using multistage cluster sampling. Serum from 4745 mature animals was tested for Brucella antibodies using the Rose-Bengal plate test and positives were confirmed in series-testing protocol using competitive enzyme-linked immunosorbent assay. Preputial scrapings from 602 bulls were tested using culture and identification for Campylobacter fetus. For each disease, a herd was classified as positive if one or more animals tested positive. For each herd, information on potential managemental and environmental risk factors was collected through a questionnaire administered during an interview with the manager, owner or herdsman. Multiple logistic regression models were used to model the odds of herd infection for each disease. A zero-inflated Poisson model was used to model the count of Brucella-positive animals within herds, with the number tested as an exposure variable. The presence of small ruminants (sheep and/or goats) on the same farm, and buying-in of >3 new animals in the previous year or failure to practice quarantine were associated with increased odds of herd-level campylobacteriosis and brucellosis, as well as increased within-herd counts of Brucella-positive animals. In addition, high rainfall, initial acquisition of animals from markets, practice of gynaecological examination and failure to practice herd prophylactic measures were positively associated with the odds of C. fetus infection in the herd. Herd size of >15, pastoral management system and presence of handling facility on the farm were associated with increased odds, and gynaecological examination with reduced odds of herd-level Brucella seropositivity. Furthermore, the zero-inflated Poisson model showed that borrowing or sharing of bulls was associated with

  15. A pathogen-specific approach towards udder health management in dairy herds: Using culture and somatic cell counts from routine herd investigations.

    PubMed

    Petzer, Inge-Marié; Karzis, Joanne; Donkin, Edward F; Webb, Edward C

    2016-01-01

    A dedicated udder health diagnostic programme was developed and used over a 15-year period in South Africa to analyse milk samples based on microbiological and cytological patterns within various groups and for individual cows and udder quarters in dairy herds. These pathogen-specific analyses are utilised for pro-active improvement and management of udder health in South African commercial dairy herds. The programme acts as a monitoring tool and identifies management areas at risk and individual cows with udder disease and uses both quarter and composite milk samples. Intra-mammary infection (IMI) is a dynamic situation and depending on the time a milk sample is taken, false-negative results may be obtained. A new IMI and an infection that is curing may both have low somatic cell counts (SCCs), masking the true bacterial status. SCC in individual infected udder quarters may differ greatly depending on the causative bacterial species, its pathogenicity, the host immune status and the environmental factors involved. A pathogen-specific udder health approach was followed with repeated herd tests to take account of these udder health dynamics. The results of the herd IMI investigation are applied in practice to assist veterinarians, udder health consultants and managers to make informed and specific detailed decisions at both a herd and on an individual cow basis regarding udder health. PMID:27608503

  16. A field study to determine the prevalence, dairy herd management systems, and fresh cow clinical conditions associated with ketosis in western European dairy herds.

    PubMed

    Berge, Anna C; Vertenten, Geert

    2014-01-01

    The aim of this study was to determine the prevalence, major management systems, and fresh cow clinical conditions associated with ketosis in western European dairy herds. A total of 131 dairies were enrolled in Germany, France, Italy, the Netherlands, and the United Kingdom during 2011 to 2012. A milk-based test for ketones (Keto-Test; Sanwa Kagaku Kenkyusho Co. Ltd., Nagoya, Japan; distributed by Elanco Animal Health, Antwerp, Belgium) was used for screening cows between d 7 and 21 after calving and ketosis was defined as a Keto-Test ≥100µmol/L. Study cows were observed for clinical disease up to 35d postcalving. Multivariate analysis (generalized estimating equation logistic regression) was performed to determine country, farm, management, feed, and cow factors associated with ketosis and to determine associations between ketosis and fresh cow diseases. Thirty-nine percent of the cows were classified as having ketosis. The herd average of ketosis was 43% in Germany, 53% in France, 31% in Italy, 46% in the Netherlands, and 31% in the United Kingdom. Of the 131 farms, 112 (85%) had 25% or more of their fresh cows resulting as positive for ketosis. Clinical ketosis was not reported in most farms and the highest level of clinical ketosis reported was 23%. The risks of ketosis were significantly lower in Italy and the United Kingdom compared with France, the Netherlands, and Germany. Larger herd size was associated with a decreased risk of ketosis. The farms that fed partially mixed rations had 1.5 times higher odds of ketosis than those that fed total mixed rations. Cows that calved in April to June had the highest odds of ketosis, with about twice as high odds compared with cows that calved in July to September. The cows that calved in January to March tended to have 1.5 times higher risk of ketosis compared with cows that calved in July to September. The odds of ketosis in parity 2 and parity 3 to 7 was significantly higher (1.5 and 2.8 times higher

  17. Prevalence and consequences of subacute ruminal acidosis in German dairy herds

    PubMed Central

    2013-01-01

    Background The prevalence and the clinical consequences of subacute ruminal acidosis (SARA) in dairy cows are still poorly understood. In order to evaluate the prevalence of SARA, 26 German dairy farms were included in a field study. In each herd, between 11 and 14 lactating dairy cows were examined for their ruminal pH using rumenocentesis. Milk production data and farm management characteristics were recorded. Each farm was scored for lameness prevalence among lactating animals, and body condition score was recorded three times four to five weeks apart in all animals examined. Farms were grouped on basis of ruminal pH and compared for lameness, body condition, milk production parameters and style of management. Animals were grouped on basis of their measured ruminal pH and compared accordingly for milk production parameters and body condition score. Results Of 315 cows examined, 63 individuals (20%) exhibited a ruminal pH of ≤ 5.5 at time of rumenocentesis. Of 26 farms examined, eleven farms had three or more of their cows experiencing a ruminal pH of ≤ 5.5 and were classified as likely experiencing subacute ruminal acidosis. These farms tended to be bigger than the others and offered less lying space to the lactating cows. There was no clear tendency regarding lameness. Among individual cows, animals with a low ruminal pH of ≤ 5.5 were found to be in significantly poorer body condition than animals with higher pH values (p < 0,05). Conclusions The study shows 11 out of 26 of herds likely experiencing SARA. Bigger herds tend to be at a higher risk for SARA, while individuals with low ruminal pH tend to be lower in body condition. The study points to the importance of management in preventing SARA. PMID:23805878

  18. Incorporation of aurochs into a cattle herd in Neolithic Europe: single event or breeding?

    PubMed Central

    Schibler, Jörg; Elsner, Julia; Schlumbaum, Angela

    2014-01-01

    Domestication is an ongoing process continuously changing the lives of animals and humans and the environment. For the majority of European cattle (Bos taurus) genetic and archaeozoological evidence support initial domestication ca. 11'000 BP in the Near East from few founder aurochs (Bos primigenius) belonging to the mitochondrial DNA T macro-haplogroup. Gene flow between wild European aurochs of P haplogroup and domestic cattle of T haplogroup, coexisting over thousands of years, appears to have been sporadic. We report archaeozoological and ancient DNA evidence for the incorporation of wild stock into a domestic cattle herd from a Neolithic lake-dwelling in Switzerland. A complete metacarpus of a small and compact adult bovid is morphologically and genetically a female. With withers height of ca. 112 cm, it is comparable in size with small domestic cattle from contemporaneous sites in the area. The bone is directly dated to 3360–3090 cal BC and associated to the Horgen culture, a period of the secondary products revolution. The cow possessed a novel mtDNA P haplotype variant of the European aurochs. We argue this is either a single event or, based on osteological characteristics of the Horgen cattle, a rare instance of intentional breeding with female aurochs. PMID:25052335

  19. Incorporation of aurochs into a cattle herd in Neolithic Europe: single event or breeding?

    NASA Astrophysics Data System (ADS)

    Schibler, Jörg; Elsner, Julia; Schlumbaum, Angela

    2014-07-01

    Domestication is an ongoing process continuously changing the lives of animals and humans and the environment. For the majority of European cattle (Bos taurus) genetic and archaeozoological evidence support initial domestication ca. 11'000 BP in the Near East from few founder aurochs (Bos primigenius) belonging to the mitochondrial DNA T macro-haplogroup. Gene flow between wild European aurochs of P haplogroup and domestic cattle of T haplogroup, coexisting over thousands of years, appears to have been sporadic. We report archaeozoological and ancient DNA evidence for the incorporation of wild stock into a domestic cattle herd from a Neolithic lake-dwelling in Switzerland. A complete metacarpus of a small and compact adult bovid is morphologically and genetically a female. With withers height of ca. 112 cm, it is comparable in size with small domestic cattle from contemporaneous sites in the area. The bone is directly dated to 3360-3090 cal BC and associated to the Horgen culture, a period of the secondary products revolution. The cow possessed a novel mtDNA P haplotype variant of the European aurochs. We argue this is either a single event or, based on osteological characteristics of the Horgen cattle, a rare instance of intentional breeding with female aurochs.

  20. Physical and thermal characteristics of dairy cattle manure.

    PubMed

    Sutitarnnontr, Pakorn; Hu, Enzhu; Tuller, Markus; Jones, Scott B

    2014-11-01

    Greenhouse and regulated gas emissions from animal waste are naturally mediated by moisture content and temperature. As with soils, emissions from manure could be readily estimated given the physical, hydraulic, and thermal properties are described by models and microbes and nutrients are not limiting factors. The objectives of this study were to measure and model physical, hydraulic, and thermal properties of dairy manure to support advanced modeling of gas and water fluxes in addition to solute, colloid, and heat transport. A series of soil science measurement techniques were applied to determine a set of fundamental properties of as-excreted dairy cattle manure. Relationships between manure dielectric permittivity and volumetric water content (θ) were obtained using time-domain reflectometry and capacitance-based dielectric measurements. The measured water retention characteristic for cattle manure was similar to organic peat soil. The unsaturated hydraulic conductivity function of dairy manure was inferred from inverse numerical fitting of laboratory manure evaporation results. The thermal properties of dairy manure, including thermal conductivity, thermal diffusivity, and bulk volumetric heat capacity, were also determined using three penta-needle heat pulse probes. The accuracy of the heat capacity measurements was determined from a comparison of theoretical θ, estimated from the measured thermal properties with that determined by the capacitance-based dielectric measurement. These data represent a novel and unique contribution for advancing prediction and modeling capabilities of gas emissions from cattle manure, although the uncertainties associated with the complexities of shrinkage, surface crust formation, and cracking must also be considered. PMID:25602228

  1. High herd-level prevalence of Mycobacterium avium subspecies paratuberculosis in Western Canadian dairy farms, based on environmental sampling.

    PubMed

    Wolf, R; Barkema, H W; De Buck, J; Slomp, M; Flaig, J; Haupstein, D; Pickel, C; Orsel, K

    2014-10-01

    Mycobacterium avium subspecies paratuberculosis (MAP) causes chronic progressive enteritis in ruminants. The pathogen is present in most countries with modern dairy production, causing substantial economic losses for the industry. The objectives of this study were to estimate dairy herd prevalence of MAP in the Western Canadian provinces of Alberta and Saskatchewan, and to determine whether herd size and housing system (tie-stall versus freestall or loose housing) affected the risk of a herd testing positive for MAP. Six environmental samples were collected on 360 Alberta farms (60% of registered producers) and on 166 Saskatchewan dairy farms (99%). In total, 47% of the sampled farms in Alberta and 53% of the sampled farms in Saskatchewan had at least one environmental sample that was MAP culture positive and were, therefore, defined as infected. Sensitivity of environmental sampling was estimated using 3 subsequent annual tests performed on 82 farms. Because laboratory protocols were continuously improved throughout the project, the sensitivity increased over time. Therefore, a mean of the sensitivity estimates weighted on sampling year was constructed; this resulted in sensitivities of 68 and 69% for Alberta and Saskatchewan, respectively. Implementing those estimates in an approximate Bayesian computation model resulted in a true herd prevalence of 68% (95% probability interval: 60-80%) for Alberta and 76% (95% probability interval: 70-85%) for Saskatchewan. Herds with >200 cows had 3.54 times higher odds of being environmental sample positive and had more positive samples than herds with <50 cows (neither province nor housing system affected those results). In conclusion, the majority of Alberta and Saskatchewan dairy farms were infected with MAP and larger herds were more often MAP positive than smaller herds.

  2. Economic analysis of Mycobacterium avium subspecies paratuberculosis vaccines in dairy herds.

    PubMed

    Cho, J; Tauer, L W; Schukken, Y H; Gómez, M I; Smith, R L; Lu, Z; Grohn, Y T

    2012-04-01

    Johne's disease, or paratuberculosis, is a chronic infectious enteric disease of ruminants, caused by infection with Mycobacterium avium ssp. paratuberculosis (MAP). Given the absence of a fail-safe method of prevention or a cure, Johne's disease can inflict significant economic loss on the US dairy industry, with an estimated annual cost of over $200 million. Currently available MAP control strategies include management measures to improve hygiene, culling MAP serologic- or fecal-positive adult cows, and vaccination. Although the 2 first control strategies have been reported to be effective in reducing the incidence of MAP infection, the changes in herd management needed to conduct these control strategies require significant effort on the part of the dairy producer. On the other hand, vaccination is relatively simple to apply and requires minor changes in herd management. Despite these advantages, only 5% of US dairy operations use vaccination to control MAP. This low level of adoption of this technology is due to limited information on its cost-effectiveness and efficacy and some important inherent drawbacks associated with current MAP vaccines. This study investigates the epidemiological effect and economic values of MAP vaccines in various stages of development. We create scenarios for the potential epidemiological effects of MAP vaccines, and then estimate economically justifiable monetary values at which vaccines become economically beneficial to dairy producers such that a net present value (NPV) of a farm's net cash flow can be higher than the NPV of a farm using no control or alternative nonvaccine controls. Any vaccination with either low or high efficacy considered in this study yielded a higher NPV compared with a no MAP control. Moreover, high-efficacy vaccines generated an even higher NPV compared with alternative controls, making vaccination economically attractive. Two high-efficacy vaccines were particularly effective in MAP control and NPV

  3. Prevalence and seasonality of bulk milk antibodies against Dictyocaulus viviparus and Ostertagia ostertagi in Irish pasture-based dairy herds.

    PubMed

    Bloemhoff, Yris; Forbes, Andrew; Good, Barbara; Morgan, Eric; Mulcahy, Grace; Strube, Christina; Sayers, Ríona

    2015-04-15

    Infections with Dictyocaulus viviparus and Ostertagia ostertagi nematode parasites are of importance to bovine health and production in temperate areas across the world. Losses due to these parasites in dairy herds can be considerable due to decreased milk productivity and fertility. However, information on current epidemiological patterns in Irish dairy herds is limited. Bulk milk samples were collected from a total of 319 dairy farms across the Republic of Ireland. The D. viviparus samples were tested with an ELISA based on recombinant major sperm protein, while the O. ostertagi samples were tested with an ELISA based on crude saline extract, whole worm O. ostertagi antigen. Management data were collected from the farms using a questionnaire. Logistic regression was used to find significant associations between the presence of antibodies against D. viviparus and O. ostertagi and management factors. The overall prevalence of D. viviparus infection was 62.8%, while over 98% of herds had antibodies to O. ostertagi at the specified cut-off. Both D. viviparus and O. ostertagi antibodies were highest in November, which could be explained by the accumulated uptake of larvae through the grazing season. In herds of farmers that dosed their in-calf heifers with anthelmintics were significantly more likely to be positive for antibodies against D. viviparus infection. This study highlights that both D. viviparus and O. ostertagi infections are widespread in dairy herds in Ireland throughout the grazing season.

  4. Prevalence and seasonality of bulk milk antibodies against Dictyocaulus viviparus and Ostertagia ostertagi in Irish pasture-based dairy herds.

    PubMed

    Bloemhoff, Yris; Forbes, Andrew; Good, Barbara; Morgan, Eric; Mulcahy, Grace; Strube, Christina; Sayers, Ríona

    2015-04-15

    Infections with Dictyocaulus viviparus and Ostertagia ostertagi nematode parasites are of importance to bovine health and production in temperate areas across the world. Losses due to these parasites in dairy herds can be considerable due to decreased milk productivity and fertility. However, information on current epidemiological patterns in Irish dairy herds is limited. Bulk milk samples were collected from a total of 319 dairy farms across the Republic of Ireland. The D. viviparus samples were tested with an ELISA based on recombinant major sperm protein, while the O. ostertagi samples were tested with an ELISA based on crude saline extract, whole worm O. ostertagi antigen. Management data were collected from the farms using a questionnaire. Logistic regression was used to find significant associations between the presence of antibodies against D. viviparus and O. ostertagi and management factors. The overall prevalence of D. viviparus infection was 62.8%, while over 98% of herds had antibodies to O. ostertagi at the specified cut-off. Both D. viviparus and O. ostertagi antibodies were highest in November, which could be explained by the accumulated uptake of larvae through the grazing season. In herds of farmers that dosed their in-calf heifers with anthelmintics were significantly more likely to be positive for antibodies against D. viviparus infection. This study highlights that both D. viviparus and O. ostertagi infections are widespread in dairy herds in Ireland throughout the grazing season. PMID:25709092

  5. Bayesian estimation of prevalence of paratuberculosis in dairy herds enrolled in a voluntary Johne's Disease Control Programme in Ireland.

    PubMed

    McAloon, Conor G; Doherty, Michael L; Whyte, Paul; O'Grady, Luke; More, Simon J; Messam, Locksley L McV; Good, Margaret; Mullowney, Peter; Strain, Sam; Green, Martin J

    2016-06-01

    Bovine paratuberculosis is a disease characterised by chronic granulomatous enteritis which manifests clinically as a protein-losing enteropathy causing diarrhoea, hypoproteinaemia, emaciation and, eventually death. Some evidence exists to suggest a possible zoonotic link and a national voluntary Johne's Disease Control Programme was initiated by Animal Health Ireland in 2013. The objective of this study was to estimate herd-level true prevalence (HTP) and animal-level true prevalence (ATP) of paratuberculosis in Irish herds enrolled in the national voluntary JD control programme during 2013-14. Two datasets were used in this study. The first dataset had been collected in Ireland during 2005 (5822 animals from 119 herds), and was used to construct model priors. Model priors were updated with a primary (2013-14) dataset which included test records from 99,101 animals in 1039 dairy herds and was generated as part of the national voluntary JD control programme. The posterior estimate of HTP from the final Bayesian model was 0.23-0.34 with a 95% probability. Across all herds, the median ATP was found to be 0.032 (0.009, 0.145). This study represents the first use of Bayesian methodology to estimate the prevalence of paratuberculosis in Irish dairy herds. The HTP estimate was higher than previous Irish estimates but still lower than estimates from other major dairy producing countries. PMID:27237395

  6. Niacin for dairy cattle: a review.

    PubMed

    Niehoff, Inka-Donata; Hüther, Liane; Lebzien, Peter

    2009-01-01

    Due to the incorporation of niacin into the coenzymes NAD and NADP, niacin is of great importance for the metabolism of man and animals. Apart from niacin in feed and endogenous formation, microbial niacin synthesis in the rumen is an important source for dairy cows. But the amount synthesised seems to differ greatly, which might be influenced by the ration fed. Many studies revealed a positive impact of a niacin supplementation on rumen protozoa, but microbial protein synthesis or volatile fatty acid production in the rumen showed inconsistent reactions to supplemental niacin. The amount of niacin reaching the duodenum is usually higher when niacin is fed. However, not the whole quantity supplemented reaches the duodenum, indicating degradation or absorption before the duodenal cannula. Furthermore, supplementation of niacin did not always lead to a higher niacin concentration in blood. Effects on other blood parameters have been inconsistent, but might be more obvious when cows are in a tense metabolic situation, for example, ketosis or if high amounts are infused post-ruminally, since ruminal degradation appears to be substantial. The same is valid for milk parameters. In the few studies where blood niacin and milk parameters have been investigated, enhanced niacin concentrations in blood did not necessarily affect milk production or composition. These results are discussed in the present review, gaps of knowledge of niacin's mode of action on the metabolism of dairy cows are identified and directions for future research are suggested.

  7. Within herd transmission and evaluation of the performance of clinical and serological diagnosis of foot-and-mouth disease in partially immune cattle herds.

    PubMed

    Gonzales, J L; Barrientos, M A; Quiroga, J L; Ardaya, D; Daza, O; Martinez, C; Orozco, C; Crowther, J; Paton, D J

    2014-10-29

    The control of foot-and-mouth disease (FMD) in vaccinated populations relies upon surveillance activities such as clinical inspections (CI) and serological monitoring. New evidence to refine current surveillance guidelines has been provided by evaluating (1) the diagnostic performance of CI and serological tests for detection of FMD virus (FMDV) non-structural proteins (NSP), and (2) the within-herd transmission of the virus in partially immune cattle. Data came from 23 affected herds during an epidemic of FMDV type O in Bolivia, in 2007. All cattle (n=957) in these herds were clinically inspected and serum samples were collected one month after the last animal with clinical signs was detected. Samples were tested for the presence of antibodies against NSP using the PANAFTOSA 3ABC-ELISA test and a subset of samples were tested using the enzyme-linked immunoelectrotransfer blot assay (EITB). Data from clinical and serological diagnoses were analysed using a Bayesian model. The sensitivity Se and specificity Sp of the tests, as well as the prevalence and the within-herd reproduction ratio R of FMDV were estimated. In addition, risk factors for infection were identified. The Se of CI, the 3ABC-ELISA and the EITB tests were estimated to be 0.30, 0.88 and 0.96 respectively. The estimated Sp, in the same order, were 0.88, 0.93 and 0.97. The within-herd prevalence of infected animals ranged from 0.04 to 0.91 and R ranged from 1.02 to 2.68. It was observed that cattle coming from areas with high vaccination coverage had a lower risk of becoming infected than home-bred cattle from the affected herds, where vaccination coverage was thought to be low. Although these estimates come from herds kept under specific conditions, they provide a reference for future surveillance design and can inform simulation models for surveillance and control of FMD in similar cattle populations.

  8. SURVIVAL OF ESCHERICHIA COLI 0157:H7 IN DAIRY CATTLE FEED WATER

    EPA Science Inventory

    Cattle feed waters from two dairy farms were used in a study to determine the survival characteristics of the bacterial pathogen Escherichia coli )157:H7 and wild-type E. coli. The E. coli 0157:H7 inoculum consisted of a consortium of isolates obtained from dairy cattle. Fresh ma...

  9. Cattle Management for Dairying in Scandinavia's Earliest Neolithic.

    PubMed

    Gron, Kurt J; Montgomery, Janet; Rowley-Conwy, Peter

    2015-01-01

    New evidence for cattle husbandry practices during the earliest period of the southern Scandinavian Neolithic indicates multiple birth seasons and dairying from its start. Sequential sampling of tooth enamel carbonate carbon and oxygen isotope ratio analyses and strontium isotopic provenancing indicate more than one season of birth in locally reared cattle at the earliest Neolithic Funnel Beaker (EN I TRB, 3950-3500 cal. B.C.) site of Almhov in Scania, Sweden. The main purpose for which cattle are manipulated to give birth in more than one season is to prolong lactation for the production of milk and dairy-based products. As this is a difficult, intensive, and time-consuming strategy, these data demonstrate complex farming practices by early Neolithic farmers. This result offers strong support for immigration-based explanations of agricultural origins in southern Scandinavia on the grounds that such a specialised skill set cannot represent the piecemeal incorporation of agricultural techniques into an existing hunter-gatherer-fisher economy.

  10. Cattle Management for Dairying in Scandinavia’s Earliest Neolithic

    PubMed Central

    Gron, Kurt J.; Montgomery, Janet; Rowley-Conwy, Peter

    2015-01-01

    New evidence for cattle husbandry practices during the earliest period of the southern Scandinavian Neolithic indicates multiple birth seasons and dairying from its start. Sequential sampling of tooth enamel carbonate carbon and oxygen isotope ratio analyses and strontium isotopic provenancing indicate more than one season of birth in locally reared cattle at the earliest Neolithic Funnel Beaker (EN I TRB, 3950-3500 cal. B.C.) site of Almhov in Scania, Sweden. The main purpose for which cattle are manipulated to give birth in more than one season is to prolong lactation for the production of milk and dairy-based products. As this is a difficult, intensive, and time-consuming strategy, these data demonstrate complex farming practices by early Neolithic farmers. This result offers strong support for immigration-based explanations of agricultural origins in southern Scandinavia on the grounds that such a specialised skill set cannot represent the piecemeal incorporation of agricultural techniques into an existing hunter-gatherer-fisher economy. PMID:26146989

  11. Cattle Management for Dairying in Scandinavia's Earliest Neolithic.

    PubMed

    Gron, Kurt J; Montgomery, Janet; Rowley-Conwy, Peter

    2015-01-01

    New evidence for cattle husbandry practices during the earliest period of the southern Scandinavian Neolithic indicates multiple birth seasons and dairying from its start. Sequential sampling of tooth enamel carbonate carbon and oxygen isotope ratio analyses and strontium isotopic provenancing indicate more than one season of birth in locally reared cattle at the earliest Neolithic Funnel Beaker (EN I TRB, 3950-3500 cal. B.C.) site of Almhov in Scania, Sweden. The main purpose for which cattle are manipulated to give birth in more than one season is to prolong lactation for the production of milk and dairy-based products. As this is a difficult, intensive, and time-consuming strategy, these data demonstrate complex farming practices by early Neolithic farmers. This result offers strong support for immigration-based explanations of agricultural origins in southern Scandinavia on the grounds that such a specialised skill set cannot represent the piecemeal incorporation of agricultural techniques into an existing hunter-gatherer-fisher economy. PMID:26146989

  12. Case-control approach application for finding a relationship between candidate genes and clinical mastitis in Holstein dairy cattle.

    PubMed

    Bagheri, Masoumeh; Moradi-Sharhrbabak, M; Miraie-Ashtiani, R; Safdari-Shahroudi, M; Abdollahi-Arpanahi, R

    2016-02-01

    Mastitis is a major source of economic loss in dairy herds. The objective of this research was to evaluate the association between genotypes within SLC11A1 and CXCR1 candidate genes and clinical mastitis in Holstein dairy cattle using the selective genotyping method. The data set contained clinical mastitis records of 3,823 Holstein cows from two Holstein dairy herds located in two different regions in Iran. Data included the number of cases of clinical mastitis per lactation. Selective genotyping was based on extreme values for clinical mastitis residuals (CMR) from mixed model analyses. Two extreme groups consisting of 135 cows were formed (as cases and controls), and genotyped for the two candidate genes, namely, SLC11A1 and CXCR1, using polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), respectively. Associations between single nucleotide polymorphism (SNP) genotypes with CMR and breeding values for milk and protein yield were carried out by applying logistic regression analyses, i.e. estimating the probability of the heterogeneous genotype in the dependency of values for CMR and breeding values (BVs). The sequencing results revealed a novel mutation in 1139 bp of exon 11 of the SLC11A1 gene and this SNP had a significant association with CMR (P < 0.05). PCR-RFLP analysis leads to three banding patterns for CXCR1c.735C>G and these genotypes had significant relationships with CMR. Overall, the results showed that SLC11A1 and CXCR1 are valuable candidate genes for the improvement of mastitis resistance as well as production traits in dairy cattle populations.

  13. Heifer fertility and carry over consequences for life time production in dairy and beef cattle.

    PubMed

    Wathes, D C; Pollott, G E; Johnson, K F; Richardson, H; Cooke, J S

    2014-05-01

    The rearing period has a key influence on the later performance of cattle, affecting future fertility and longevity. Producers usually aim to breed replacement heifers by 15 months to calve at 24 months. An age at first calving (AFC) close to 2 years (23 to 25 months) is optimum for economic performance as it minimises the non-productive period and maintains a seasonal calving pattern. This is rarely achieved in either dairy or beef herds, with average AFC for dairy herds usually between 26 and 30 months. Maintaining a low AFC requires good heifer management with adequate growth to ensure an appropriate BW and frame size at calving. Puberty should occur at least 6 weeks before the target breeding age to enable animals to undergo oestrous cycles before mating. Cattle reach puberty at a fairly consistent, but breed-dependent, proportion of mature BW. Heifer fertility is a critical component of AFC. In US Holsteins the conception rate peaked at 57% at 15 to 16 months, declining in older heifers. Wide variations in growth rates on the same farm often lead to some animals having delayed first breeding and/or conception. Oestrous synchronisation regimes and sexed semen can both be used but unless heifers have been previously well-managed the success rates may be unacceptably low. Altering the nutritional input above or below those needed for maintenance at any stage from birth to first calving clearly alters the average daily gain (ADG) in weight. In general an ADG of around 0.75 kg/day seems optimal for dairy heifers, with lower rates delaying puberty and AFC. There is some scope to vary ADG at different ages providing animals reach an adequate size by calving. Major periods of nutritional deficiency and/or severe calfhood disease will, however, compromise development with long-term adverse consequences. Infectious disease can also cause pregnancy loss/abortion. First lactation milk yield may be slightly lower in younger calving cows but lifetime production is higher as

  14. Economic effect of bovine abortion syndrome in commercial dairy herds in Southern Chile.

    PubMed

    Gädicke, P; Vidal, R; Monti, G

    2010-10-01

    Bovine abortion is a limiting factor for dairy business, as it decreases milk production and the potential, number of herd replacements, increases feeding and medical treatment costs, increases the number of artificial inseminations to obtain a calf as well as culling rates of cows. An estimation of the economic impact of abortion in dairy farms in Chile is not available yet. The aim of this study was to estimate the economic consequences of bovine abortion syndrome (BAS) in dairy cows from Chile. A stochastic model was proposed to evaluate the cost of an abortion on a yearly basis to include variability in cost and income by dairy and by year. The marginal total net revenue (ΔTNR) for a typical, lactation was obtained by the calculating the difference between total revenues (retail milk and calf sales) and total expenses (production cost (cows, feeding, labor, health) plus administrative and, general costs) for lactation with and without abortion. Production data were obtained from a retrospective study of 127 dairy herds located in southern Chile between 2000 and 2006. Milk production from cows with and without abortion was estimated by a mixed model using milk test day data. Production cost and prices paid to farmers were obtained from service company records (TODOAGRO S.A.). Cost and income value was corrected for inflation and expressed in the values from 2006. In addition, a separate analysis for different parities (1, 2, 3 or more) was performed. Distributions for the stochastic variables were obtained by fitting distributions from our database using @Risk. The stochastic variables included in the analysis were all related to income, feeding, depreciation, health, Artificial Insemination and general costs like fuel, salaries, taxes, etc. There was a high probability (89.20%) of a negative ΔTNR in lactations with abortion for overall, parities, with a mean loss of $ -143.32. Stratifying by parity, the predicted mean of the distribution for ΔTNR in each

  15. Economic effect of bovine abortion syndrome in commercial dairy herds in Southern Chile.

    PubMed

    Gädicke, P; Vidal, R; Monti, G

    2010-10-01

    Bovine abortion is a limiting factor for dairy business, as it decreases milk production and the potential, number of herd replacements, increases feeding and medical treatment costs, increases the number of artificial inseminations to obtain a calf as well as culling rates of cows. An estimation of the economic impact of abortion in dairy farms in Chile is not available yet. The aim of this study was to estimate the economic consequences of bovine abortion syndrome (BAS) in dairy cows from Chile. A stochastic model was proposed to evaluate the cost of an abortion on a yearly basis to include variability in cost and income by dairy and by year. The marginal total net revenue (ΔTNR) for a typical, lactation was obtained by the calculating the difference between total revenues (retail milk and calf sales) and total expenses (production cost (cows, feeding, labor, health) plus administrative and, general costs) for lactation with and without abortion. Production data were obtained from a retrospective study of 127 dairy herds located in southern Chile between 2000 and 2006. Milk production from cows with and without abortion was estimated by a mixed model using milk test day data. Production cost and prices paid to farmers were obtained from service company records (TODOAGRO S.A.). Cost and income value was corrected for inflation and expressed in the values from 2006. In addition, a separate analysis for different parities (1, 2, 3 or more) was performed. Distributions for the stochastic variables were obtained by fitting distributions from our database using @Risk. The stochastic variables included in the analysis were all related to income, feeding, depreciation, health, Artificial Insemination and general costs like fuel, salaries, taxes, etc. There was a high probability (89.20%) of a negative ΔTNR in lactations with abortion for overall, parities, with a mean loss of $ -143.32. Stratifying by parity, the predicted mean of the distribution for ΔTNR in each

  16. Short communication: Streptococcus canis is able to establish a persistent udder infection in a dairy herd.

    PubMed

    Król, Jarosław; Twardoń, Jan; Mrowiec, Jacek; Podkowik, Magdalena; Dejneka, Grzegorz; Dębski, Bogdan; Nowicki, Tadeusz; Zalewski, Wojciech

    2015-10-01

    Bovine mastitis caused by Streptococcus canis is relatively rare. Consequently, many epidemiologic aspects of the infection, including factors that mediate crossing of host species barriers by the pathogen, infectiousness of the microorganism to the mammary gland, and the course of the disease within a herd, are still not elucidated. Therefore, the aim of the present study was to describe results of a 15-mo observation of subclinical Strep. canis mastitis on a dairy farm housing 76 lactating Holstein-Friesian cows. Upon 3 visits to the farm during a period between April 2013 and June 2014, Strep. canis was cultured from milk samples of 17 (22.4% of the herd), 7 (9.6%), and 8 (11.3%) cows, respectively. The isolates obtained were characterized phenotypically by means of the API Strep identification kit (bioMérieux, Marcy l'Etoile, France), as well as genetically by using random amplified polymorphic DNA and macrorestriction analysis of the chromosomal DNA by pulsed-field gel electrophoresis. All strains displayed the same biochemical features, and the molecular methods revealed that the isolates belonged to a single clone or were very closely related. Results of the study indicate that Strep. canis is capable of causing intramammary infections of long duration, behaving in a contagious manner. Because a persistently infected cow may serve as the source of Strep. canis infection for other animals, effective control of this type of udder infection within a herd may require similar measures to those adopted in Streptococcus agalactiae eradication programs.

  17. Metabolic profiles in five high-producing Swedish dairy herds with a history of abomasal displacement and ketosis

    PubMed Central

    Stengärde, Lena; Tråvén, Madeleine; Emanuelson, Ulf; Holtenius, Kjell; Hultgren, Jan; Niskanen, Rauni

    2008-01-01

    Background Body condition score and blood profiles have been used to monitor management and herd health in dairy cows. The aim of this study was to examine BCS and extended metabolic profiles, reflecting both energy metabolism and liver status around calving in high-producing herds with a high incidence of abomasal displacement and ketosis and to evaluate if such profiles can be used at herd level to pinpoint specific herd problems. Methods Body condition score and metabolic profiles around calving in five high-producing herds with high incidences of abomasal displacement and ketosis were assessed using linear mixed models (94 cows, 326 examinations). Cows were examined and blood sampled every three weeks from four weeks ante partum (ap) to nine weeks postpartum (pp). Blood parameters studied were glucose, fructosamine, non-esterified fatty acids (NEFA), insulin, β-hydroxybutyrate, aspartate aminotransferase, glutamate dehydrogenase, haptoglobin and cholesterol. Results All herds had overconditioned dry cows that lost body condition substantially the first 4–6 weeks pp. Two herds had elevated levels of NEFA ap and three herds had elevated levels pp. One herd had low levels of insulin ap and low levels of cholesterol pp. Haptoglobin was detected pp in all herds and its usefulness is discussed. Conclusion NEFA was the parameter that most closely reflected the body condition losses while these losses were not seen in glucose and fructosamine levels. Insulin and cholesterol were potentially useful in herd profiles but need further investigation. Increased glutamate dehydrogenase suggested liver cell damage in all herds. PMID:18687108

  18. Prospects for the genetic manipulation of dairy cattle: opportunities beyond BST.

    PubMed

    Jones, D D; Cordle, M K

    1995-01-01

    The dairy industry, with regulatory approvals of recombinant chymosin and bovine somatotropin (BST), has been at the forefront of food and agricultural biotechnology. The commercial fate of these products is one of several factors that may affect the success of future genetic manipulations in dairy cattle and dairy products. Other factors include technical and reproductive constraints in cattle and the cost of producing transgenic cattle. Early applications of genetic manipulation in cattle, for reasons of cost recoupment, may favor production of heterologous proteins in milk for pharmaceutical and medical use. Such applications could benefit genetic modification of milk and milk proteins for food use by providing advance knowledge and experience in mammalian protein expression. Other research opportunity areas that could affect prospects for genetic manipulation of dairy cattle include genome mapping, metabolic pathways, growth and development, and cattle/microbe interactions.

  19. Major advances associated with reproduction in dairy cattle.

    PubMed

    Moore, K; Thatcher, W W

    2006-04-01

    The purpose of this overview is to review some of the major advances in reproductive technologies, and how they may be applied to meet the challenge of enhancing reproductive efficiency in the high-producing dairy cow of the 21st century. The current population of high-producing dairy cows is considered to be subfertile, as characterized by low pregnancy rates and high rates of embryonic mortality. Coordinated systems of reproductive management have been developed based upon a thorough understanding of the endocrine, cellular, and molecular factors controlling ovarian and uterine function. These systems will partially restore herd reproductive performance. Advances in other reproductive technologies offer possibilities for wider use of superior germplasm. Technologies such as sexed semen, cloning, transgenesis, and preimplantation genetic diagnosis offer the potential to enhance the influence of superior animals on production of food for human consumption. However, at this time, additional research is needed to counteract the higher rates of embryonic and fetal mortality associated with some of these technologies. Furthermore, use of genomics, proteomics, and bioinformatics in the study of reproduction will undoubtedly provide investigators with a greater understanding of the limitations to efficient reproductive processes in the subfertile lactating dairy cow. PMID:16537958

  20. The effect of lactation length on greenhouse gas emissions from the national dairy herd.

    PubMed

    Wall, E; Coffey, M P; Pollott, G E

    2012-11-01

    Many governments have signed up to greenhouse gas emission (GHGE) reduction programmes under their national climate change obligations. Recently, it has been suggested that the use of extended lactations in dairy herds could result in reduced GHGE. Dairy GHGE were modelled on a national basis and the model was used to compare emissions from lactations of three different lengths (305, 370 and 440 days), and a current 'base' scenario on the basis of maintaining current milk production levels. In addition to comparing GHGE from the average 'National Herd' under these scenarios, results were used to investigate how accounting for lactations of different lengths might alter the estimation of emissions calculated from the National Inventory methodology currently recommended by Intergovernmental Panel on Climate Change. Data for the three lactation length scenarios were derived from nationally recorded dairy performance information and used in the GHGE model. Long lactations required fewer milking cows and replacements to maintain current milk yield levels than short ones, but GHGEs were found to rise from 1214 t of CO2 equivalent (CE)/farm per year for lactations of 305 days to 1371 t CE/farm per year for 440-day lactations. This apparent anomaly can be explained by the less efficient milk production (kg milk produced per kg cow weight) found in later lactation, a more pronounced effect in longer lactations. The sensitivity of the model to changes in replacement rate, persistency and level of milk yield was investigated. Changes in the replacement rate from 25% to 20% and in persistency by −10% to +20% resulted in very small changes in GHGE. Differences in GHGE due to the level of milk yield were much more dramatic with animals in the top 10% for yield, producing about 25% less GHGE/year than the average animal. National Inventory results were investigated using a more realistic spread of lactation lengths than recommended for such calculations using emissions

  1. Genotypes and Antibiotic Resistances of Campylobacter jejuni Isolates from Cattle and Pigeons in Dairy Farms

    PubMed Central

    Bianchini, Valentina; Luini, Mario; Borella, Laura; Parisi, Antonio; Jonas, Romie; Kittl, Sonja; Kuhnert, Peter

    2014-01-01

    Campylobacter jejuni is the most common food-borne zoonotic pathogen causing human gastroenteritis worldwide and has assumed more importance in Italy following the increased consumption of raw milk. Our objectives were to get an overview of genotypes and antibiotic resistances in C. jejuni isolated from milk, cattle feces, and pigeons in dairy herds of Northern Italy. flaB-typing was applied to 78 C. jejuni isolates, previously characterized by Multi-Locus Sequence Typing, and genotypic resistances towards macrolides and quinolones based on point mutations in the 23S rRNA and gyrA genes, respectively, were determined. flaB-typing revealed 22 different types with one of them being novel and was useful to further differentiate strains with an identical Sequence Type (ST) and to identify a pigeon-specific clone. Macrolide resistance was not found, while quinolone resistance was detected in 23.3% of isolates. A relationship between specific genotypes and antibiotic resistance was observed, but was only significant for the Clonal Complex 206. Our data confirm that pigeons do not play a role in the spread of C. jejuni among cattle and they are not responsible for milk contamination. A relevant number of bulk milk samples were contaminated by C. jejuni resistant to quinolones, representing a possible source of human resistant strains. PMID:25026083

  2. Analysis of Q fever in Dutch dairy goat herds and assessment of control measures by means of a transmission model.

    PubMed

    Bontje, D M; Backer, J A; Hogerwerf, L; Roest, H I J; van Roermund, H J W

    2016-01-01

    Between 2006 and 2009 the largest human Q fever epidemic ever described occurred in the Netherlands. The source of infection was traced back to dairy goat herds with abortion problems due to Q fever. The first aim of control measures taken in these herds was the reduction of human exposure. To analyze Q fever dynamics in goat herds and to study the effect of control measures, a within-herd model of Coxiella burnetii transmission in dairy goat herds was developed. With this individual-based stochastic model we evaluated six control strategies and three herd management styles and studied which strategy leads to a lower Q fever prevalence and/or to disease extinction in a goat herd. Parameter values were based on literature and on experimental work. The model could not be validated with independent data. The results of the epidemiological model were: (1) Vaccination is effective in quickly reducing the prevalence in a dairy goat herd. (2) When taking into account the average time to extinction of the infection and the infection pressure in a goat herd, the most effective control strategy is preventive yearly vaccination, followed by the reactive strategies to vaccinate after an abortion storm or after testing BTM (bulk tank milk) positive. (3) As C. burnetii in dried dust may affect public health, an alternative ranking method is based on the cumulative amount of C. burnetii emitted into the environment (from disease introduction until extinction). Using this criterion, the same control strategies are effective as when based on time to extinction and infection pressure (see 2). (4) As the bulk of pathogen excretion occurs during partus and abortion, culling of pregnant animals during an abortion storm leads to a fast reduction of the amount of C. burnetii emitted into the environment. However, emission is not entirely prevented and Q fever will not be eradicated in the herd by this measure. (5) A search & destroy (i.e. test and cull) method by PCR of individual milk

  3. Comparison of modeled sampling strategies for estimation of dairy herd lameness prevalence and cow-level variables associated with lameness.

    PubMed

    Hoffman, A C; Moore, D A; Wenz, J R; Vanegas, J

    2013-09-01

    Monitoring herd lameness prevalence has utility for dairy producers and veterinarians in their efforts to reduce lameness, for animal welfare assessment programs, and for researchers. Locomotion scoring is a method used to quantify lameness and calculate prevalence. Because of the time necessary to locomotion score each cow in large dairy herds, a sampling strategy to determine herd lameness prevalence that allows scoring of fewer cows would be useful. Such a sampling strategy must be validated for accuracy compared with the lameness prevalence when all cows in a herd are locomotion scored. The purpose of this study was to assess 3 previously suggested methods of estimating lameness prevalence by strategic sampling of dairy herds. Sampling strategies tested included (1) sampling a calculated number of cows in the middle third of the milking parlor exit order for each pen, (2) sampling a calculated number of cows weighted across pens and distributed evenly within each pen, and (3) sampling all cows in the high production, low production, and hospital pens. Lactating cows on 5 dairy farms in Washington and Oregon (n=4,422) were locomotion scored using a 5-point scale to determine herd-level lameness prevalence (percentage with locomotion score ≥3). Milking parlor exit order, order in headlocks at the feed bunk within each pen, and breed were recorded for each cow. The number of days in lactation, milk production, and parity were collected from farm computer records. Pen grouping strategy for each farm was obtained by interview with farm management. Sampling strategies were modeled using the locomotion score data set for each herd. Estimates of lameness prevalence obtained from the milking parlor exit order sample and the sample distributed across pens were within 5 percentage points of the whole herd prevalence. The third strategy estimated the lameness prevalence within 5 percentage points on 4 farms, but overestimated prevalence on 1 farm. Pen-level prevalence

  4. Analysis of Q fever in Dutch dairy goat herds and assessment of control measures by means of a transmission model.

    PubMed

    Bontje, D M; Backer, J A; Hogerwerf, L; Roest, H I J; van Roermund, H J W

    2016-01-01

    Between 2006 and 2009 the largest human Q fever epidemic ever described occurred in the Netherlands. The source of infection was traced back to dairy goat herds with abortion problems due to Q fever. The first aim of control measures taken in these herds was the reduction of human exposure. To analyze Q fever dynamics in goat herds and to study the effect of control measures, a within-herd model of Coxiella burnetii transmission in dairy goat herds was developed. With this individual-based stochastic model we evaluated six control strategies and three herd management styles and studied which strategy leads to a lower Q fever prevalence and/or to disease extinction in a goat herd. Parameter values were based on literature and on experimental work. The model could not be validated with independent data. The results of the epidemiological model were: (1) Vaccination is effective in quickly reducing the prevalence in a dairy goat herd. (2) When taking into account the average time to extinction of the infection and the infection pressure in a goat herd, the most effective control strategy is preventive yearly vaccination, followed by the reactive strategies to vaccinate after an abortion storm or after testing BTM (bulk tank milk) positive. (3) As C. burnetii in dried dust may affect public health, an alternative ranking method is based on the cumulative amount of C. burnetii emitted into the environment (from disease introduction until extinction). Using this criterion, the same control strategies are effective as when based on time to extinction and infection pressure (see 2). (4) As the bulk of pathogen excretion occurs during partus and abortion, culling of pregnant animals during an abortion storm leads to a fast reduction of the amount of C. burnetii emitted into the environment. However, emission is not entirely prevented and Q fever will not be eradicated in the herd by this measure. (5) A search & destroy (i.e. test and cull) method by PCR of individual milk

  5. Seroprevalence of chlamydial infection in dairy cattle in Guangzhou, southern China

    PubMed Central

    2013-01-01

    Chlamydia spp. are obligate intracellular gram-negative bacteria that cause a wide range of significant diseases in humans and animals worldwide, resulting in significant economic losses. Chlamydial infection in cattle has been reported in many countries including China. However, there has been no survey of chlamydial infection of dairy cattle in Guangzhou, southern China. The objective of the present investigation was to examine the chlamydial seroprevalence in dairy cattle in Guangzhou, subtropical southern China by using an indirect hemagglutination assay (IHA). The overall seroprevalence of chlamydial infection in dairy cattle was 7.25% (29/400). Greater than or equal to eight-yr-old dairy cattle had the highest seroprevalence (10.34%), followed by those that were ≥ 6 years old or < 7 years old dairy cattle (10.20%), although there were no statistically significant differences among different groups (P > 0.05). Dairy cattle with 5 pregnancies had the highest seroprevalence (10.81%). These results indicate that chlamydial infection was present in dairy cattle in Guangzhou, subtropical southern China, and integrated strategies and measures should be executed to control and prevent chlamydial infection and disease outbreak in the study region. PMID:23379717

  6. Fecal shedding of thermophilic Campylobacter in a dairy herd producing raw milk for direct human consumption.

    PubMed

    Merialdi, Giuseppe; Giacometti, Federica; Bardasi, Lia; Stancampiano, Laura; Taddei, Roberta; Serratore, Patrizia; Serraino, Andrea

    2015-03-01

    Factors affecting the fecal shedding of thermophilic Campylobacter in Italian dairy farms were investigated in a 12-month longitudinal study performed on a dairy farm authorized to sell raw milk in Italy. Fifty animals were randomly selected from 140 adult and young animals, and fecal samples were collected six times at 2-month intervals. At each sampling time, three trough water samples and two trough feed samples also were collected for both adult and young animals. Samples were analyzed with real-time PCR assay and culture examination. Overall, 33 samples (9.7%) were positive for thermophilic Campylobacter by real-time PCR: 26 (9.2%) of 280 fecal samples, 6 (16.6%) of 36 water samples, and 1 (4.2%) of 24 feed samples. Campylobacter jejuni was isolated from 6 of 280 samples; no other Campylobacter species was isolated. A higher (but not significantly) number of positive fecal samples were found in younger animals (11.33 versus 6.92% of adult animals), and a significantly higher number of positive water samples were collected from the water troughs of young animals. A distinct temporal trend was observed during the study period for both cows and calves, with two prevalence peaks between November and December and between May and July. Several factors such as calving, housing practices, herd size, management practices forcing together a higher number of animals, and variations in feed or water sources (previously reported as a cause of temporal variation in different farming conditions) were excluded as the cause of the two seasonal peaks in this study. The factors affecting the seasonality of Campylobacter shedding in the dairy herds remain unclear and warrant further investigation. The results of the present study indicate that special attention should be paid to farm hygiene management on farms authorized to produce and sell raw milk, with increased surveillance by the authorities at certain times of the year.

  7. Evaluation of complementary diagnostic tools for bovine tuberculosis detection in dairy herds from India

    PubMed Central

    Thakur, Mukesh Kumar; Sinha, Dharmender Kumar; Singh, Bhoj Raj

    2016-01-01

    Aim: A cross-sectional study was undertaken to know the herd prevalence and evaluate the single intradermal tuberculin testing (SITT), culture isolation, and polymerase chain reaction (PCR) analysis for the diagnosis of bovine tuberculosis (TB). Materials and Methods: A total of 541 cows of three dairy farms of Bareilly and Mukteshwar were screened by SITT followed by collection of pre-scapular lymph node (PSLN) aspirates (71), milk (54), and blood (71) samples from reactor animals. These clinical samples were processed for culture isolation and direct PCR-based identification and species differentiation. Results: Out of 541 cows screened by SITT, 71 (13.12%) animals were found positive. Mycobacteria were isolated from 3 (4.22%) PSLN aspirate but not from any cultured milk and blood samples. 28 (39.43%) PSLN aspirate and 5 (9.25%) milk samples were positive for Mycobacterium TB (MTB) complex (MTC) by PCR amplification for the IS6110 insertion sequence; however, blood samples were found negative. For species differentiation, multiplex-PCR using 12.7 kb primers was conducted. Out of 28 PSLN aspirate, Mycobacterium bovis was detected in 18 (64.28%) and MTB in 8 (28.57%), whereas 2 aspirate samples (7.14%) were positive for both the species. All the five milk positive samples were positive for M. bovis. Conclusion: Direct detection of bovine TB by a molecular-based method in dairy animals after preliminary screening was appeared to be more sensitive and specific compared to the conventional method (i.e., culture isolation). Its application in form of serial testing methodology for the routine diagnosis and thereafter, culling of infected stock may be suggested for the control programs in dairy herds. The PSLN aspirate was found to be the most suitable specimen for culture isolation and PCR-based detection of Mycobacterium spp. among live infected animals. PMID:27651675

  8. Evaluation of complementary diagnostic tools for bovine tuberculosis detection in dairy herds from India

    PubMed Central

    Thakur, Mukesh Kumar; Sinha, Dharmender Kumar; Singh, Bhoj Raj

    2016-01-01

    Aim: A cross-sectional study was undertaken to know the herd prevalence and evaluate the single intradermal tuberculin testing (SITT), culture isolation, and polymerase chain reaction (PCR) analysis for the diagnosis of bovine tuberculosis (TB). Materials and Methods: A total of 541 cows of three dairy farms of Bareilly and Mukteshwar were screened by SITT followed by collection of pre-scapular lymph node (PSLN) aspirates (71), milk (54), and blood (71) samples from reactor animals. These clinical samples were processed for culture isolation and direct PCR-based identification and species differentiation. Results: Out of 541 cows screened by SITT, 71 (13.12%) animals were found positive. Mycobacteria were isolated from 3 (4.22%) PSLN aspirate but not from any cultured milk and blood samples. 28 (39.43%) PSLN aspirate and 5 (9.25%) milk samples were positive for Mycobacterium TB (MTB) complex (MTC) by PCR amplification for the IS6110 insertion sequence; however, blood samples were found negative. For species differentiation, multiplex-PCR using 12.7 kb primers was conducted. Out of 28 PSLN aspirate, Mycobacterium bovis was detected in 18 (64.28%) and MTB in 8 (28.57%), whereas 2 aspirate samples (7.14%) were positive for both the species. All the five milk positive samples were positive for M. bovis. Conclusion: Direct detection of bovine TB by a molecular-based method in dairy animals after preliminary screening was appeared to be more sensitive and specific compared to the conventional method (i.e., culture isolation). Its application in form of serial testing methodology for the routine diagnosis and thereafter, culling of infected stock may be suggested for the control programs in dairy herds. The PSLN aspirate was found to be the most suitable specimen for culture isolation and PCR-based detection of Mycobacterium spp. among live infected animals.

  9. Estimation of the economical effects of Eimeria infections in Estonian dairy herds using a stochastic model.

    PubMed

    Lassen, Brian; Ostergaard, Søren

    2012-10-01

    In this study, a stochastic predictive model stimulating a constant infection pressure of Eimeria was used to estimate production outcome, economic, and effects of treatment decisions in a dairy herd of 100 cows. The intestinal parasite cause problems mainly in calves, and is known to have long term effects on the growth rate, and in severe cases can result in mortalities. Due to the inconspicuous nature of the parasite, the clinical signs and sub-clinical manifestations it may produce can be overlooked. Acquired data from literature and Estonian dairy farms were implemented in the SimHerd IV model to simulate three scenarios of symptomatic treatment: no calves treated (NT), default estimate of the current treatment strategy (DT), and all calves treated (AT). Effects of metaphylactic treatment were studied as a lowering of the infection pressure. Delay in the age for beginning of insemination of heifers was the effect with the largest economic impact on the gross margin, followed by calf mortality and reduction in growth rate. Large expenses were associated with the introduction of replacement heifers and feeding of heifers as a result of the delay in reaching a specific body weight at calving. Compared to the control scenarios, with no effects and treatments of Eimeria, dairy farmers were estimated to incur annual losses ranging 8-9% in the balanced income. Providing metaphylactic drugs resulted in an increased gross margin of 6-7%. Purchase of new heifers compensated for some production losses that would otherwise have enhanced expenses related to Eimeria. The simulation illustrates how effects of Eimeria infections can have long lasting impact on interacting management factors. It was concluded that all three simulated symptomatic treatment regimes provided only small economic benefits if they were applied alone and not in combination with lowering of infection pressure.

  10. Prevalence and persistence of coagulase-negative Staphylococcus species in three dairy research herds.

    PubMed

    Gillespie, B E; Headrick, S I; Boonyayatra, S; Oliver, S P

    2009-02-16

    Coagulase-negative Staphylococcus species (CNS) were isolated from 11.3% (1407 of 12,412) of mammary quarter milk samples obtained from cows in three dairy research herds in 2005. Approximately 27% (383/1407) of CNS was identified to the species level. The species distribution among those CNS identified from all herds was Staphylococcus chromogenes (48%), Staphylococcus hyicus (26%), Staphylococcus epidermidis (10%), Staphylococcus simulans (7%), Staphylococcus warneri (2%), Staphylococcus hominis (2%), Staphylococcus saprophyticus (1%), Staphylococcus xylosus (1%), Staphylococcus haemolyticus (<1%), Staphylococcus sciuri (<1%), and Staphylococcus intermedius (<1%). Staphylococcuschromogenes was the predominant CNS isolated from all three herds; however, differences were seen in the prevalence of other CNS species. A total of 158 CNS (S. chromogenesn=66, S. hyicusn=38, S. epidermidisn=37, S. simulans n=10, and S. warneri n=7) were analyzed by pulsed-field gel electrophoresis (PFGE). The majority (33/41) of CNS isolated from the same mammary quarter on more than one occasion had the same PFGE pattern indicating persistence of the same infection over time. When all PFGE patterns for each CNS were analyzed, no common pulsotype was seen among the three herds indicating that CNS are quite diverse. Composite milk somatic cell count (SCC) data were obtained +/-14d of when CNS were isolated. Average milk SCC (5.32 log(10)/ml) for cows in which CNS was the only bacteria isolated was significantly higher than the average milk SCC (4.90 log(10)/ml) from cows with quarter milk samples that were bacteriologically negative.

  11. An epidemiologic study of disease in 32 registered Holstein dairy herds in British Columbia.

    PubMed

    van Dorp, R T; Martin, S W; Shoukri, M M; Noordhuizen, J P; Dekkers, J C

    1999-07-01

    Data recorded in a herd health management system were obtained from 32 registered Holstein dairy herds from British Columbia. Frequencies of disease were described, and the effect of herd, age, year, season, and the interrelationships between diseases within a lactation on the occurrence of disease were evaluated. Lactational incidence rates were computed for diseases with a short period of risk (ie, udder edema, milk fever, retained placenta, metritis, displaced abomasum, and ketosis), whereas for diseases with a longer period of risk (ie, cystic ovaries, mastitis and stable footrot), incidence densities were calculated. Overall, the disease incidence was low and showed an increase in frequency by year, which we attributed to more observing and complete recording by the owner, rather than an actual increase in disease incidence. Most diseases occurred early in lactation and their frequency increased with lactation number; the exception was udder edema, which occurred mainly during the first 2 lactations. An informal path model of disease interrelationships was made conditional on herd. Based on the results we inferred 2 independent pathways: one started by udder edema, and the other by milk fever. Udder edema was directly associated with mastitis occurrence from 0 to 30 d in lactation, metritis, and cystic ovaries. Mastitis from 0-30 d in lactation increased the risk of both mastitis from 31-150 d in lactation and cystic ovaries. Both of these increased the risk of late lactation mastitis. Milk fever was directly related with displaced abomasum, which increased the risk of footrot. In general, diseases that occurred in early lactation tended to increase the risk of other diseases later in lactation.

  12. Prevalence and multilocus genotyping of Cryptosporidium andersoni in dairy cattle and He cattle in Xinjiang, China.

    PubMed

    Qi, Meng; Wang, Rongjun; Jing, Bo; Jian, Fuchun; Ning, Changshen; Zhang, Longxian

    2016-10-01

    Cryptosporidium andersoni is the predominant species in post-weaned and adult cattle in China. The aim of this study was to determine the prevalence and understand the transmission of cattle cryptosporidiosis in the Xinjiang Uyghur Autonomous Region, China, a total of 1827 fecal samples (436 from He cattle and 1391 from dairy cattle) were examined for the presence of C. andersoni-like oocysts by microscopy after Sheather's sugar flotation technique. The overall prevalence of C. andersoni-like was 3.8% (70/1827) and all the C. andersoni-like isolates were identified as C. andersoni at the SSU rRNA locus. Among the C. andersoni isolates, a total of 60 isolates were successfully characterized into eight multilocus sequence typing (MLST) subtypes using MLST analysis at the four microsatellite/minisatellite loci (MS1, MS2, MS3 and MS16), and three new subtypes were identified. The MLST subtype A4,A4,A4,A1 showed a predominance and a wide distribution among the eight MLST subtypes obtained in the investigated areas. The MLST subtypes A2,A4,A2,A1 and A4,A5,A2,A1 showed a unique distribution in the investigated areas. A linkage disequilibrium analysis showed the presence of an epidemic population genetic structure of C. andersoni isolated from dairy and He cattle in Xinjiang. These findings provide new insights into the genetic structure of C. andersoni isolates and are also helpful to explore the infection source of C. andersoni in cattle in Xinjiang, China. PMID:27448954

  13. Prevalence and multilocus genotyping of Cryptosporidium andersoni in dairy cattle and He cattle in Xinjiang, China.

    PubMed

    Qi, Meng; Wang, Rongjun; Jing, Bo; Jian, Fuchun; Ning, Changshen; Zhang, Longxian

    2016-10-01

    Cryptosporidium andersoni is the predominant species in post-weaned and adult cattle in China. The aim of this study was to determine the prevalence and understand the transmission of cattle cryptosporidiosis in the Xinjiang Uyghur Autonomous Region, China, a total of 1827 fecal samples (436 from He cattle and 1391 from dairy cattle) were examined for the presence of C. andersoni-like oocysts by microscopy after Sheather's sugar flotation technique. The overall prevalence of C. andersoni-like was 3.8% (70/1827) and all the C. andersoni-like isolates were identified as C. andersoni at the SSU rRNA locus. Among the C. andersoni isolates, a total of 60 isolates were successfully characterized into eight multilocus sequence typing (MLST) subtypes using MLST analysis at the four microsatellite/minisatellite loci (MS1, MS2, MS3 and MS16), and three new subtypes were identified. The MLST subtype A4,A4,A4,A1 showed a predominance and a wide distribution among the eight MLST subtypes obtained in the investigated areas. The MLST subtypes A2,A4,A2,A1 and A4,A5,A2,A1 showed a unique distribution in the investigated areas. A linkage disequilibrium analysis showed the presence of an epidemic population genetic structure of C. andersoni isolated from dairy and He cattle in Xinjiang. These findings provide new insights into the genetic structure of C. andersoni isolates and are also helpful to explore the infection source of C. andersoni in cattle in Xinjiang, China.

  14. Niacin in dairy and beef cattle nutrition.

    PubMed

    Flachowsky, G

    1993-01-01

    Niacin functions metabolically as a component of the coenzymes NAD and NADP. Sources of niacin are feedstuffs and the enzymatic conversion of tryptophan and quinolinic acid into niacin. Niacin is synthesized by the microflora in the rumen of ruminants. Recent research suggests that microbial production of niacin may not be sufficient for the requirements of high producing cows. Supplemental niacin given to cows in early lactation may reduce the rate of fat mobilization, decrease the concentration of ketones in blood and increase blood glucose level. Niacin supplementation may increase propionate concentration and decrease butyrate concentration in rumen liquor. Ruminal microbial protein synthesis was enhanced by niacin. Not all experiments showed such clear results. The positive metabolic effects of niacin supplementation have resulted in most studies in an improved milk yield (3-4%) especially during early lactation. The milk constituents were mostly uninfluenced or only minimally increased. Reasons for the high variations of results are differences in ration formulation, level of milk performance, stage of lactation, age of cows, body conditions, level and duration of niacin supplementation and specific experimental conditions. Niacin supplemented cows lost less body weight during early lactation, were less days open and required fewer pellets per pregnancy. It would appear that niacin supplementation of about 6 grams per animal per day (200-400 mg per kg dry matter) for the first 60 to 100 days of lactation may be beneficial in selected high producing cows or heifers. In beef cattle niacin supplementation would appear to be beneficial (approximately 1 g per animal per day or about 100 mg per kg dry matter) when the body weight of bulls is lower than 300 kg, when the diets are poor in protein (10 tp 12% crude protein of dry matter) and during dietary adaptation periods.

  15. A systematic review of risk factors associated with the introduction of Mycobacterium avium spp. paratuberculosis (MAP) into dairy herds

    PubMed Central

    Rangel, Saray J.; Paré, Julie; Doré, Elizabeth; Arango, Juan C.; Côté, Geneviève; Buczinski, Sebastien; Labrecque, Olivia; Fairbrother, Julie H.; Roy, Jean P.; Wellemans, Vincent; Fecteau, Gilles

    2015-01-01

    The objective of this study was to systematically collect and appraise the scientific evidence related to risk factors associated with the introduction of Mycobacterium avium spp. paratuberculosis (MAP) into a herd of cattle. An electronic search was conducted to collect relevant references addressing 2 specific questions: are i) purchasing/introduction of cattle into a herd, and ii) presence of wildlife or domestic animals, risk factors for the introduction of MAP into a herd? The screening was based on titles and abstracts and selected studies were fully analyzed. Seventeen manuscripts published between 1996 and 2011 were ultimately analyzed. Unit of interest was mainly the herd (n = 17). The specific description of the risk factors studied varied between studies. The principal study design was cross-sectional (n = 15). The review indicated that purchase/introduction of animals was an important risk factor and that the importance of wildlife or other domestic species as a mechanism for transmission into a cattle herd was not measurable. PMID:25694667

  16. Bovine leukemia virus becomes established in dairy herds before the first lactation.

    PubMed

    Merlini, Ramiro; Gutiérrez, Gerónimo; Alvarez, Irene; Jaworski, Juan Pablo; Carignano, Hugo; Poli, Mario; Willems, Luc; Trono, Karina

    2016-11-01

    In this work, we studied seven groups of pregnant heifers from a consortium of dairy farms heavily infected with bovine leukemia virus (BLV). ELISA testing showed that the seroprevalence ranges of BLV in heifers between 36.1 and 66.5 %. No significant differences in proviral load were found when comparing heifers with adult cattle. Before their first delivery, more than 9.8 % of heifers show a high proviral load. Because BLV infection can occur during the first two years of life, the rationale of any strategy should be to take action as early as possible after birth.

  17. Comparison of E. coli O157 and Shiga toxin-encoding genes (stx) prevalence between Ohio, USA and Norwegian dairy cattle.

    PubMed

    LeJeune, Jeffrey T; Hancock, Dale; Wasteson, Yngvild; Skjerve, Eystein; Urdahl, Anne Margrete

    2006-05-25

    Environmental and food contamination with Shiga toxin-producing Escherichia coli (STEC) pose a threat to public health worldwide, with notable geographic differences in incidence of human disease caused by these organisms. The prevalence of E. coli O157 and total stx-positive specimens collected from mature dairy cattle in Ohio and Norwegian dairy farms was compared using identical laboratory methods in a cross-sectional survey. E. coli O157 was isolated from 5/750 (0.66%) of Ohio dairy cows from 4/50 (8%) different herds, whereas E. coli O157 was not isolated from any (0/680) cattle present in 50 Norwegian dairy herds. In contrast, at least one stx-positive faecal sample was identified by PCR on all (50/50) Norwegian farms but only on 70% (35/50) of Ohio farms. Average animal stx prevalence on Ohio farms was also lower; 14% vs. 61% in Ohio and Norwegian herds, respectively. Livestock feed contamination with generic E. coli was uncommon in Norway, 1/50 feeds testing positive, whereas 19/50 (38%) of feeds collected from Ohio farms were contaminated, some as high as 10(5) CFU/g. Despite extreme differences in on-farm management practices between countries, stx appear to be widely disseminated in cattle in both countries, while the human pathogenic O157 serotype is less widely disseminated in Norway than it is in Ohio. Geographic distribution differences of human pathogenic STEC serogroups in the bovine reservoir, as opposed to specific farm management practices affecting on farm STEC prevalence, may be an important defining factor influencing the incidence of human illnesses associated in different areas of the world.

  18. Postpartum uterine diseases and their impacts on conception and days open in dairy herds in Italy.

    PubMed

    Toni, F; Vincenti, L; Ricci, A; Schukken, Y H

    2015-10-15

    The objective of this study was to describe the incidence and the impact of postpartum uterine diseases in postpartum cows on future uterine status and reproductive performance in large Italian dairy herds. This study provides an important quantitative estimate of uterine and postpartum diseases incidence that afflict high-producing Italian dairy cows. The total number of cows included in the study was 1498 on three farms; all cows were followed from the dry period until 300 days postpartum. All farms used high-quality data collection systems and standard operating procedures: weekly herd health visits, monthly Dairy Herd Improvement Association visits, and, due to cheese-making milk quality requirements, a supplementary milk sample collected at 7 ± 3 days postpartum evaluated for milk components. Clinical metritis in primiparous cows did not change the time to the first artificial insemination (AI) or days open; conversely, clinical metritis in multiparous cows had impact on the time to first AI (hazard ratio: 0.66, P < 0.01) and resulted in a lower conception rate at first insemination and a increase in days open (odds ratio: 0.64, P < 0.05). Clinical endometritis had a strong deleterious effect on first AI conception rate (odds ratio: 0.34, P < 0.05) and days open across all lactations (hazard ratio: 0.68, P < 0.05). Persistent metritis, defined as the presence of both clinical metritis and clinical endometritis in the same animal in the same lactation, caused low conception rate both in the first-lactation and in older cows and had a strong negative effect on the proportion of pregnant cows at 300 days (P < 0.05). In conclusion, the impact of endometritis on fertility was true across lactation groups. A good management and precocious diagnosis of the pathologies is not resolutive to restore good fertility parameters, and understanding the immune response in first-lactation cows may be of value for developing alternative intervention protocols for older

  19. New findings of Enterocytozoon bieneusi in beef and dairy cattle in Brazil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Microsporidia are widely recognized as important human pathogens with Enterocytozoon bieneusi as the most common species infecting humans and animals, including cattle. Although Brazil has the second largest cattle herd in the world and it is the largest exporter of beef there are no data on the pre...

  20. Seroprevalence and correlates of Toxoplasma gondii infection in dairy cattle in northwest China.

    PubMed

    Tan, Qi-Dong; Yang, Xiao-Yu; Yin, Ming-Yang; Hu, Ling-Ying; Qin, Si-Yuan; Wang, Jin-Lei; Zhou, Dong-Hui; Zhu, Xing-Quan

    2015-12-01

    Prevalence of antibodies to Toxoplasma gondii and risk factors with infection were assessed in dairy cattle from Gansu Province and Ningxia Hui Autonomous Region (NXHAR), northwest China. In total, 1657 serum samples were collected and assayed by the modified agglutination test. The overall seroprevalence was 4.83% at a 1:100 cut-off, with titers of 1:100 in 72, 1:200 in 4, 1:400 in 4. Among the risk factors examined, no statistically significant difference was observed between T. gondii seroprevalence and regions or age of dairy cattle in the logistic regression analysis (P>0.05) and left out of the final model. However, numbers of pregnancies of dairy cattle was considered as main risk factor associated with T. gondii infection. Dairy cattle in nulliparity group (8.89%) had 6 times (OR=6.31, 95% CI, 2.69-14.83, P<0.001) higher risk of being seropositive compared to dairy cattle in 3 or above 3 pregnancies group (1.52%), followed by 1 pregnancy group (4.27%) had nearly 3 times (OR=2.89, 95% CI, 1.11-7.52, P = 0.03) higher risk of being seropositive compared to dairy cattle in 3 or above 3 pregnancies group, although no statistical difference was found between 2 pregnancies group and 3 or above 3 pregnancies group (P = 0.70). The results of this survey indicated the presence of T. gondii infection in dairy cattle in Gansu Province and NXHAR, which enriches the epidemiological data of T. gondii infection in dairy cattle in China, and is helpful to strengthen prevention and control of T. gondii infection in dairy cattle in these two regions.

  1. Hepatocyte apoptosis in dairy cattle during the transition period.

    PubMed

    Tharwat, Mohamed; Takamizawa, Aya; Hosaka, Yoshinao Z; Endoh, Daiji; Oikawa, Shin

    2012-10-01

    The objective of this study was to investigate hepatocyte apoptosis in dairy cows during the transition period. Four clinically healthy, pregnant dairy cattle were used. The cows had no clinical diseases throughout this study. Blood samples were collected and livers were biopsied from the cows at 3 different times: 3 weeks before expected partition (wk -3); during parturition (wk 0), and 3 weeks (wk +3) after parturition. The damage to deoxyribonucleic acid (DNA) caused by hepatocytes was evaluated by comet assay. The apoptotic features of hepatocytes were examined by immunohistochemistry and electron microscopic analyses. The hepatic triglyceride content markedly increased at wk 0 and wk +3 compared with the values at wk -3. The results of the comet assay showed increases in the mean tail moment values of hepatic cells after parturition in all cows, which suggested increased DNA damage. Histopathologically, the hepatocytes began to contain lipid droplets at wk 0 and were severely opacified at wk +3. Caspase-3-positive and single-stranded DNA-(ssDNA)-positive cells were first detected in the liver after parturition. Condensation of nuclear chromatin, a typical sign of apoptosis, was confirmed by transmission electron microscopy after parturition. These results suggest that apoptosis is induced in hepatocytes of dairy cows around parturition and may result from lipotoxicity in hepatocytes.

  2. Farm management factors associated with bulk tank total bacterial count in Irish dairy herds during 2006/07

    PubMed Central

    2009-01-01

    Research has shown that total bacterial count (TBC), which is the bacterial growth per ml of milk over a fixed period of time, can be decreased by good hygiene and farm management practices. The objective of the current study was to quantify the associations between herd management factors and bulk tank TBC in Irish spring calving, grass-based dairy herds. The relationship between bulk tank TBC and farm management and infrastructure was examined using data from 400 randomly selected Irish dairy farms where the basal diet was grazed grass. Herd management factors associated with bulk tank TBC were identified using linear models with herd annual total bacterial score (i.e., arithmetic mean of the natural logarithm of bulk tank TBC) included as the dependent variable. All herd management factors were individually analysed in a separate regression model, that included an adjustment for geographical location of the farm. A multiple stepwise regression model was subsequently developed. Median bulk tank TBC for the sample herds was 18,483 cells/ml ranging from 10,441 to 130,458 cells/ml. Results from the multivariate analysis indicated that the following management practices were associated with low TBC; use of heated water in the milking parlour; participation in a milk recording scheme; and tail clipping of cows at a frequency greater than once per year. Increased level of hygiene of the parlour and cubicles were also associated with lower TBC. Herd management factors associated with bulk tank TBC in Irish grazing herds were generally in agreement with most previous studies from confinement systems of milk production. PMID:21851723

  3. The seroprevalence of Johne's disease in Georgia beef and dairy cull cattle.

    PubMed

    Pence, Mel; Baldwin, Charles; Black, C Carter

    2003-09-01

    Beef and dairy cattle serum samples, collected during 2000 at sale barns throughout Georgia, were obtained from the Georgia State Brucellosis Laboratory and were used to conduct a retrospective epidemiological study. Statistical samplings of 5,307 sera, from over 200,000 sera, were tested for antibodies to Mycobacterium avium ssp. paratuberculosis, (Johne's disease) using a commercial enzyme-linked immunosorbent assay test kit. An overall period seroprevalence in all classes of cattle tested was 4.73%. The period seroprevalence in dairy cattle was 9.58%, in beef cattle it was 3.95%, and in cattle of unknown breed it was 4.72%. It was concluded that the seroprevalence of Johne's disease in cull beef and dairy cattle in Georgia is economically significant.

  4. Invited review: Enteric methane in dairy cattle production: quantifying the opportunities and impact of reducing emissions.

    PubMed

    Knapp, J R; Laur, G L; Vadas, P A; Weiss, W P; Tricarico, J M

    2014-01-01

    Many opportunities exist to reduce enteric methane (CH4) and other greenhouse gas (GHG) emissions per unit of product from ruminant livestock. Research over the past century in genetics, animal health, microbiology, nutrition, and physiology has led to improvements in dairy production where intensively managed farms have GHG emissions as low as 1 kg of CO2 equivalents (CO2e)/kg of energy-corrected milk (ECM), compared with >7 kg of CO2 e/kg of ECM in extensive systems. The objectives of this review are to evaluate options that have been demonstrated to mitigate enteric CH4 emissions per unit of ECM (CH4/ECM) from dairy cattle on a quantitative basis and in a sustained manner and to integrate approaches in genetics, feeding and nutrition, physiology, and health to emphasize why herd productivity, not individual animal productivity, is important to environmental sustainability. A nutrition model based on carbohydrate digestion was used to evaluate the effect of feeding and nutrition strategies on CH4/ECM, and a meta-analysis was conducted to quantify the effects of lipid supplementation on CH4/ECM. A second model combining herd structure dynamics and production level was used to estimate the effect of genetic and management strategies that increase milk yield and reduce culling on CH4/ECM. Some of these approaches discussed require further research, but many could be implemented now. Past efforts in CH4 mitigation have largely focused on identifying and evaluating CH4 mitigation approaches based on nutrition, feeding, and modifications of rumen function. Nutrition and feeding approaches may be able to reduce CH4/ECM by 2.5 to 15%, whereas rumen modifiers have had very little success in terms of sustained CH4 reductions without compromising milk production. More significant reductions of 15 to 30% CH4/ECM can be achieved by combinations of genetic and management approaches, including improvements in heat abatement, disease and fertility management, performance

  5. Invited review: Enteric methane in dairy cattle production: quantifying the opportunities and impact of reducing emissions.

    PubMed

    Knapp, J R; Laur, G L; Vadas, P A; Weiss, W P; Tricarico, J M

    2014-01-01

    Many opportunities exist to reduce enteric methane (CH4) and other greenhouse gas (GHG) emissions per unit of product from ruminant livestock. Research over the past century in genetics, animal health, microbiology, nutrition, and physiology has led to improvements in dairy production where intensively managed farms have GHG emissions as low as 1 kg of CO2 equivalents (CO2e)/kg of energy-corrected milk (ECM), compared with >7 kg of CO2 e/kg of ECM in extensive systems. The objectives of this review are to evaluate options that have been demonstrated to mitigate enteric CH4 emissions per unit of ECM (CH4/ECM) from dairy cattle on a quantitative basis and in a sustained manner and to integrate approaches in genetics, feeding and nutrition, physiology, and health to emphasize why herd productivity, not individual animal productivity, is important to environmental sustainability. A nutrition model based on carbohydrate digestion was used to evaluate the effect of feeding and nutrition strategies on CH4/ECM, and a meta-analysis was conducted to quantify the effects of lipid supplementation on CH4/ECM. A second model combining herd structure dynamics and production level was used to estimate the effect of genetic and management strategies that increase milk yield and reduce culling on CH4/ECM. Some of these approaches discussed require further research, but many could be implemented now. Past efforts in CH4 mitigation have largely focused on identifying and evaluating CH4 mitigation approaches based on nutrition, feeding, and modifications of rumen function. Nutrition and feeding approaches may be able to reduce CH4/ECM by 2.5 to 15%, whereas rumen modifiers have had very little success in terms of sustained CH4 reductions without compromising milk production. More significant reductions of 15 to 30% CH4/ECM can be achieved by combinations of genetic and management approaches, including improvements in heat abatement, disease and fertility management, performance

  6. National survey of clinical and subclinical mastitis in Jamaican dairy herds, 1985-1986.

    PubMed

    Zingeser, J; Daye, Y; Lopez, V; Grant, G; Bryan, L; Kearney, M; Hugh-Jones, M E

    1991-02-01

    Between April 1985 and August 1986, 89 Jamaican dairy herds with 10 or more cows were visited, 1,645 lactating cows were examined using the CMT test and 254 composite milk samples collected for bacteriological examination. Widespread management faults were noted, especially of milking machine usage and maintenance and the abuse of antibiotics. Fifty-six per cent of all quarters were found to have CMT scores of one or higher, 0.8% showed clinical mastitis and 3.2% were blind. The most common bacterial pathogen Staphylococcus aureus, was recovered from 31% of sampled cows. The resultant milk loss from clinical and subclinical mastitis was estimated to be 20% of the potential national production.

  7. Effect of exposure to Neospora caninum, Salmonella, and Leptospira interrogans serovar Hardjo on the economic performance of Irish dairy herds.

    PubMed

    O' Doherty, E; Sayers, R; O' Grady, L; Shalloo, L

    2015-04-01

    The objective of the current study was to quantify the effects of exposure to Salmonella, Neospora caninum, and Leptospira interrogans serovar Hardjo (L. hardjo) on dairy farm profitability and to simulate the effect of vaccination for Salmonella and L. hardjo on dairy farm profitability. The production effects associated with exposure to each of these pathogens in study herds were defined under 3 categories: (1) milk production effects, (2) reproduction effects (including culling), and (3) mortality effects. The production effects associated with exposure to Salmonella, N. caninum, and L. hardjo were incorporated into the Moorepark Dairy Systems Model. In the analysis, herds negative for exposure to Salmonella, N. caninum, and L. hardjo were assumed baseline herds, with all results presented relative to this base. In simulations examining the effect of vaccination for Salmonella and L. hardjo on farm profitability, vaccinated herds (vaccination costs included) were considered as baseline herds and results were presented relative to this base. Total annual profits in unvaccinated herds were reduced by €77.31, €94.71, and €112.11 per cow at milk prices of €0.24, €0.29, and €0.34/L, respectively, as a result of exposure to Salmonella. In the current study, herds positive for exposure to Salmonella recorded a 316-kg reduction in milk yield, whereas no association was detected between exposure to N. caninum or L. hardjo and milk production. Exposure to both N. caninum and L. hardjo was associated with compromised reproductive performance. Herds positive for exposure to N. caninum and Salmonella had greater rates of adult cow mortality and calf mortality, respectively. Vaccination for both Salmonella and L. hardjo was associated with improved performance in study herds. Exposure to N. caninum resulted in a reduction in annual farm profits of €11.55, €12, and €12.44 per cow at each milk price, whereas exposure to L. hardjo resulted in a reduction in

  8. Epidemiology of subclinical ketosis in early lactation dairy cattle.

    PubMed

    McArt, J A A; Nydam, D V; Oetzel, G R

    2012-09-01

    The purpose of this study was to describe the epidemiology of subclinical ketosis (SCK) in dairy cows in early lactation and determine the association of (1) days in milk (DIM) at onset of SCK, and (2) blood β-hydroxybutyrate (BHBA) concentration at onset of SCK with development of displaced abomasum (DA) and removal from herd in the first 30 DIM, conception to first service, days to conception within 150 DIM, and early lactation milk yield. Cows from 4 freestall dairy herds (2 in New York and 2 in Wisconsin) were each tested 6 times for SCK from 3 to 16 DIM using the Precision Xtra meter (Abbott Laboratories, Abbott Park, IL). Subclinical ketosis was defined as a BHBA concentration of 1.2 to 2.9 mmol/L. Mixed-effects multivariable Poisson regression was used to assess DA, removal from herd, and conception to first service. Semiparametric proportional hazards models were used to evaluate days to conception, and repeated-measures ANOVA was used to evaluate milk yield in the first 30 DIM. A total of 741 of 1,717 (43.2%) eligible cows had a least one BHBA test of 1.2 to 2.9 mmol/L. Peak incidence of SCK occurred at 5 DIM, when 22.3% of cows had their first SCK-positive test. Peak prevalence of SCK occurred at 5 DIM, when 28.9% of cows had a SCK-positive test. Median time from first positive SCK test until BHBA test <1.2 mmol/L was 5d. Cows first testing SCK positive from 3 to 5 DIM were 6.1 times more likely [95% confidence interval (CI) = 2.3 to 16.0] to develop a DA than cows first testing SCK positive at 6 DIM or later. Cows first testing SCK positive from 3 to 7 DIM were 4.5 times more likely (95% CI = 1.7 to 11.7) to be removed from the herd, were 0.7 times as likely (95% CI = 0.6 to 0.8) to conceive to first service, and produced 2.2 kg less milk per day for the first 30 DIM than cows first testing positive at 8 DIM or later. Each 0.1 mmol/L increase in BHBA at first SCK-positive test increased the risk of developing a DA by a factor of 1.1 (95% CI = 1.0 to 1

  9. Short communication: Streptococcus canis is able to establish a persistent udder infection in a dairy herd.

    PubMed

    Król, Jarosław; Twardoń, Jan; Mrowiec, Jacek; Podkowik, Magdalena; Dejneka, Grzegorz; Dębski, Bogdan; Nowicki, Tadeusz; Zalewski, Wojciech

    2015-10-01

    Bovine mastitis caused by Streptococcus canis is relatively rare. Consequently, many epidemiologic aspects of the infection, including factors that mediate crossing of host species barriers by the pathogen, infectiousness of the microorganism to the mammary gland, and the course of the disease within a herd, are still not elucidated. Therefore, the aim of the present study was to describe results of a 15-mo observation of subclinical Strep. canis mastitis on a dairy farm housing 76 lactating Holstein-Friesian cows. Upon 3 visits to the farm during a period between April 2013 and June 2014, Strep. canis was cultured from milk samples of 17 (22.4% of the herd), 7 (9.6%), and 8 (11.3%) cows, respectively. The isolates obtained were characterized phenotypically by means of the API Strep identification kit (bioMérieux, Marcy l'Etoile, France), as well as genetically by using random amplified polymorphic DNA and macrorestriction analysis of the chromosomal DNA by pulsed-field gel electrophoresis. All strains displayed the same biochemical features, and the molecular methods revealed that the isolates belonged to a single clone or were very closely related. Results of the study indicate that Strep. canis is capable of causing intramammary infections of long duration, behaving in a contagious manner. Because a persistently infected cow may serve as the source of Strep. canis infection for other animals, effective control of this type of udder infection within a herd may require similar measures to those adopted in Streptococcus agalactiae eradication programs. PMID:26233445

  10. Frequency and causes of infectious abortion in a dairy herd in Queretaro, Mexico

    PubMed Central

    Escamilla, H. Patricia; Martínez, M. José Juan; Medina, C. Mario; Morales, S. Elizabeth

    2007-01-01

    The objective of this study was to determine the frequency of infectious bovine abortion and to identify some of its causes, specifically brucellosis, leptospirosis, bovine viral diarrhea, infectious bovine rhinotracheitis, and neosporosis. The study was carried out in a dairy herd in the state of Queretaro, Mexico, between September 2002 and March 2003. At the beginning of the study, blood samples were taken from a random 33% of the 300 lactating or pregnant cows; antibodies against Leptospira interrogans were the most commonly identified, in 91% of the 99 samples. Blood samples were also taken 14 to 28 d after the 26 subsequent abortions in the herd in the 6-mo study period, as well as from 22 cows that had not aborted within 5 d after the abortions in the other group. Seroconversion was most frequent for L. hardjo, occurring in 8 (67%) of the 12 dams that aborted after the initial serologic sampling and for which paired serum samples were therefore available. Of the 16 collected fetuses, 10 had histologic lesions suggesting infection in various organs, the features correlating with the serologic results for the dams in 7 cases. Thus, the abortions may have been caused by more than 1 infectious agent. PMID:17955907

  11. Frequency and causes of infectious abortion in a dairy herd in Queretaro, Mexico.

    PubMed

    Escamilla, H Patricia; Martínez, M José Juan; Medina, C Mario; Morales, S Elizabeth

    2007-10-01

    The objective of this study was to determine the frequency of infectious bovine abortion and to identify some of its causes, specifically brucellosis, leptospirosis, bovine viral diarrhea, infectious bovine rhinotracheitis, and neosporosis. The study was carried out in a dairy herd in the state of Queretaro, Mexico, between September 2002 and March 2003. At the beginning of the study, blood samples were taken from a random 33% of the 300 lactating or pregnant cows; antibodies against Leptospira interrogans were the most commonly identified, in 91% of the 99 samples. Blood samples were also taken 14 to 28 d after the 26 subsequent abortions in the herd in the 6-mo study period, as well as from 22 cows that had not aborted within 5 d after the abortions in the other group. Seroconversion was most frequent for L. hardjo, occurring in 8 (67%) of the 12 dams that aborted after the initial serologic sampling and for which paired serum samples were therefore available. Of the 16 collected fetuses, 10 had histologic lesions suggesting infection in various organs, the features correlating with the serologic results for the dams in 7 cases. Thus, the abortions may have been caused by more than 1 infectious agent.

  12. A case-control study to estimate the effects of acute clinical infection with the Schmallenberg virus on milk yield, fertility and veterinary costs in Swiss dairy herds.

    PubMed

    Wüthrich, M; Lechner, I; Aebi, M; Vögtlin, A; Posthaus, H; Schüpbach-Regula, G; Meylan, M

    2016-04-01

    Schmallenberg virus (SBV) was first detected in Switzerland in July 2012 and many Swiss dairy farmers reported acute clinical signs in dairy cattle during the spread of the virus until December 2012. The objectives of the present study were to investigate the effects of an acute infection with SBV on milk yield, fertility and veterinary costs in dairy farms with clinical signs of SBV infection (case farms), and to compare those farms to a matched control group of dairy farms in which cattle did not show clinical signs of SBV infection. Herd size was significantly (p<0.001) larger in case farms (33 cows, n=77) than in control farms (25 cows, n=84). Within case herds, 14.8% (median) of the cows showed acute clinical signs. Managers from case farms indicated to have observed a higher abortion rate during the year with SBV (6.5%) than in the previous year (3.7%). Analysis of fertility parameters based on veterinary bills and data from the breeding associations showed no significant differences between case and control farms. The general veterinary costs per cow from July to December 2012 were significantly higher (p=0.02) in case (CHF 19.80; EUR 16.50) than in control farms (CHF 15.90; EUR 13.25). No differences in milk yield were found between groups, but there was a significant decrease in milk production in case farms in the second half year in 2012 compared to the same period in 2011 (p<0.001) and 2013 (p=0.009). The average daily milk yield per cow (both groups together) was +0.73kg higher (p=0.03) in the second half year 2011 and +0.52kg (p=0.12) in the second half year 2013 compared to the same half year 2012. Fifty-seven percent of the cows with acute clinical signs (n=461) were treated by a veterinarian. The average calculated loss after SBV infection for a standardized farm was CHF 1606 (EUR 1338), which can be considered as low at the national level, but the losses were subject to great fluctuations between farms, so that individual farms could have very

  13. Exploring the characteristics and dynamics of Ontario dairy herds experiencing increases in bulk milk somatic cell count during the summer.

    PubMed

    Shock, D A; LeBlanc, S J; Leslie, K E; Hand, K; Godkin, M A; Coe, J B; Kelton, D F

    2015-06-01

    Regionally aggregated bulk milk somatic cell count (BMSCC) data from around the world shows a repeatable cyclicity, with the highest levels experienced during warm, humid seasons. No studies have evaluated this seasonal phenomenon at the herd level. The objectives of this study were to define summer seasonality in BMSCC on an individual herd basis, and subsequently to describe the characteristics and dynamics of herds with increased BMSCC in the summer. The data used for this analysis were from all dairy farms in Ontario, Canada, between January 2000 and December 2011 (n≈4,000 to 6,000 herds/yr). Bulk milk data were obtained from the milk marketing board and consisted of bulk milk production, components (fat, protein, lactose, other solids), and quality (BMSCC, bacterial count, inhibitor presence, freezing point), total milk quota of the farm, and milk quota and incentive fill percentage. A time-series linear mixed model, with random slopes and intercepts, was constructed using sine and cosine terms as predictors to describe seasonality, with herd as a random effect. For each herd, seasonality was described with reference to 1 cosine function of variable amplitude and phase shift. The predicted months of maximal and minimal BMSCC were then calculated. Herds were assigned as low, medium, and high summer increase (LSI, MSI, and HSI, respectively) based on percentiles of amplitude in BMSCC change for each of the 4 seasons. Using these seasonality classifications, 2 transitional repeated measures logistic regression models were built to assess the characteristics of MSI and HSI herds, using LSI herds as controls. Based on the analyses performed, a history of summer BMSCC increases increased the odds of experiencing a subsequent increase. As herd size decreased, the odds of experiencing HSI to MSI in BMSCC increased. Herds with more variability in daily BMSCC were at higher odds of experiencing MSI and HSI in BMSCC, as were herds with lower annual mean BMSCC. Finally

  14. Exploring the characteristics and dynamics of Ontario dairy herds experiencing increases in bulk milk somatic cell count during the summer.

    PubMed

    Shock, D A; LeBlanc, S J; Leslie, K E; Hand, K; Godkin, M A; Coe, J B; Kelton, D F

    2015-06-01

    Regionally aggregated bulk milk somatic cell count (BMSCC) data from around the world shows a repeatable cyclicity, with the highest levels experienced during warm, humid seasons. No studies have evaluated this seasonal phenomenon at the herd level. The objectives of this study were to define summer seasonality in BMSCC on an individual herd basis, and subsequently to describe the characteristics and dynamics of herds with increased BMSCC in the summer. The data used for this analysis were from all dairy farms in Ontario, Canada, between January 2000 and December 2011 (n≈4,000 to 6,000 herds/yr). Bulk milk data were obtained from the milk marketing board and consisted of bulk milk production, components (fat, protein, lactose, other solids), and quality (BMSCC, bacterial count, inhibitor presence, freezing point), total milk quota of the farm, and milk quota and incentive fill percentage. A time-series linear mixed model, with random slopes and intercepts, was constructed using sine and cosine terms as predictors to describe seasonality, with herd as a random effect. For each herd, seasonality was described with reference to 1 cosine function of variable amplitude and phase shift. The predicted months of maximal and minimal BMSCC were then calculated. Herds were assigned as low, medium, and high summer increase (LSI, MSI, and HSI, respectively) based on percentiles of amplitude in BMSCC change for each of the 4 seasons. Using these seasonality classifications, 2 transitional repeated measures logistic regression models were built to assess the characteristics of MSI and HSI herds, using LSI herds as controls. Based on the analyses performed, a history of summer BMSCC increases increased the odds of experiencing a subsequent increase. As herd size decreased, the odds of experiencing HSI to MSI in BMSCC increased. Herds with more variability in daily BMSCC were at higher odds of experiencing MSI and HSI in BMSCC, as were herds with lower annual mean BMSCC. Finally

  15. Prevalence of bovine viral diarrhea virus (BVDV) in persistently infected cattle and BVDV subtypes in affected cattle in beef herds in south central United States

    PubMed Central

    Fulton, Robert W.; Whitley, Evan M.; Johnson, Bill J.; Ridpath, Julia F.; Kapil, Sanjay; Burge, Lurinda J.; Cook, Billy J.; Confer, Anthony W.

    2009-01-01

    The prevalence of bovine viral diarrhea virus (BVDV) in persistently infected (PI) cattle in beef breeding herds was determined using 30 herds with 4530 calves. The samples were collected by ear notches and tested for BVDV antigens using immunohistochemistry (IHC) and antigen capture enzyme-linked immunosorbent assay (ACE). Animals with initial positives on both IHC and ACE were sampled again using both tests and serums were collected for viral propagation and sequencing of a viral genomic region, 5′-untranslated region (5′-UTR) for viral subtyping. Samples were also collected from the dams of PI calves. There were 25 PI calves from 4530 samples (0.55%) and these PI calves were from 5 of the 30 herds (16.7%). Two herds had multiple PI calves and 3 herds had only 1 PI calf. Only 1 of the 25 dams with a PI calf was also PI (4.0%). The subtype of all the PI isolates was BVDV1b. Histories of the ranches indicated 23 out of 30 had herd additions of untested breeding females. Twenty-four of the 30 herds had adult cowherd vaccinations against BVDV, primarily using killed BVDV vaccines at pregnancy examination. PMID:20046630

  16. Prevalence of bovine viral diarrhea virus (BVDV) in persistently infected cattle and BVDV subtypes in affected cattle in beef herds in south central United States.

    PubMed

    Fulton, Robert W; Whitley, Evan M; Johnson, Bill J; Ridpath, Julia F; Kapil, Sanjay; Burge, Lurinda J; Cook, Billy J; Confer, Anthony W

    2009-10-01

    The prevalence of bovine viral diarrhea virus (BVDV) in persistently infected (PI) cattle in beef breeding herds was determined using 30 herds with 4530 calves. The samples were collected by ear notches and tested for BVDV antigens using immunohistochemistry (IHC) and antigen capture enzyme-linked immunosorbent assay (ACE). Animals with initial positives on both IHC and ACE were sampled again using both tests and serums were collected for viral propagation and sequencing of a viral genomic region, 5'-untranslated region (5'-UTR) for viral subtyping. Samples were also collected from the dams of PI calves. There were 25 PI calves from 4530 samples (0.55%) and these PI calves were from 5 of the 30 herds (16.7%). Two herds had multiple PI calves and 3 herds had only 1 PI calf. Only 1 of the 25 dams with a PI calf was also PI (4.0%). The subtype of all the PI isolates was BVDV1b. Histories of the ranches indicated 23 out of 30 had herd additions of untested breeding females. Twenty-four of the 30 herds had adult cowherd vaccinations against BVDV, primarily using killed BVDV vaccines at pregnancy examination.

  17. Prevalence of bovine viral diarrhea virus (BVDV) in persistently infected cattle and BVDV subtypes in affected cattle in beef herds in south central United States.

    PubMed

    Fulton, Robert W; Whitley, Evan M; Johnson, Bill J; Ridpath, Julia F; Kapil, Sanjay; Burge, Lurinda J; Cook, Billy J; Confer, Anthony W

    2009-10-01

    The prevalence of bovine viral diarrhea virus (BVDV) in persistently infected (PI) cattle in beef breeding herds was determined using 30 herds with 4530 calves. The samples were collected by ear notches and tested for BVDV antigens using immunohistochemistry (IHC) and antigen capture enzyme-linked immunosorbent assay (ACE). Animals with initial positives on both IHC and ACE were sampled again using both tests and serums were collected for viral propagation and sequencing of a viral genomic region, 5'-untranslated region (5'-UTR) for viral subtyping. Samples were also collected from the dams of PI calves. There were 25 PI calves from 4530 samples (0.55%) and these PI calves were from 5 of the 30 herds (16.7%). Two herds had multiple PI calves and 3 herds had only 1 PI calf. Only 1 of the 25 dams with a PI calf was also PI (4.0%). The subtype of all the PI isolates was BVDV1b. Histories of the ranches indicated 23 out of 30 had herd additions of untested breeding females. Twenty-four of the 30 herds had adult cowherd vaccinations against BVDV, primarily using killed BVDV vaccines at pregnancy examination. PMID:20046630

  18. Arsenic toxicosis and suspected chromium toxicosis in a herd of cattle.

    PubMed

    Thatcher, C D; Meldrum, J B; Wikse, S E; Whittier, W D

    1985-07-15

    Arsenic toxicosis and suspected chromium toxicosis were diagnosed in a herd of cattle that ingested ashes from lumber treated with copper, chromium, and arsenic. Findings included peracute death, depression, ataxia, weakness, recumbency, and watery diarrhea. Chemical analyses of liver, kidney, abomasal contents, rumen contents, and ashes revealed high concentrations of arsenic and chromium. Histologically, specimens of abomasum and duodenum had diffuse mucosal degeneration and engorged capillaries. Epithelial cells of the proximal convoluted tubules and distal collecting tubules of the kidney were swollen and had mild granular cytoplasmic degeneration. Burning lumber treated with copper, chromium, and arsenic does not remove the heavy metals from them, and ingestion of the ashes from the wood constitutes a hazard to livestock health.

  19. Evaluation of Two PCR Tests for Coxiella burnetii Detection in Dairy Cattle Farms Using Latent Class Analysis

    PubMed Central

    Hoch, Thierry; Guatteo, Raphaël; Beaudeau, François

    2015-01-01

    Different tests performed on bulk tank milk samples (BTM) are available to determine the C. burnetii status of herds. However, these tests, which are based on the detection of either antibodies directed against C. burnetii (ELISA) or bacterial DNA (PCR), have limitations. A currently disease-free herd infected in the past may continue to test positive with ELISA due to the persistence of antibodies in animals that were infected and that subsequently cleared the infection. Infectious herds can also be misclassified using PCR because of the absence of bacteria in the BTM when the test is performed. Recently, PCR has been used for bacterial DNA detection in the farm environment, which constitutes the main reservoir of C. burnetii. The objectives of this study were to assess and compare the sensitivities and specificities of one commonly used PCR test in BTM (PCR BTM) and of a PCR applied to environmental samples (PCR DUST) in dairy cattle farms. BTM and dust samples were collected (using environmental swabs) in 95 herds. The evaluation of the performance of the 2 tests was conducted using latent class models accounting for within herd disease dynamics. Parameter estimation was carried out using MCMC, within a Bayesian framework. Two types of priors were used for the specificity of PCR DUST. A model with a uniform prior on 0–1 fitted the data better than a model with a uniform prior on 0.95–1. With the best model PCR DUST had a lower sensitivity than PCR BTM (0.75 versus 0.83) and a specificity of 0.72. The moderately low value for the specificity of PCR DUST suggests that the presence of bacteria on farm is not always associated with persistent infections and shedding of bacteria in milk. PMID:26673419

  20. The use of bulk-tank milk ELISAs to assess the spatial distribution of Fasciola hepatica, Ostertagia ostertagi and Dictyocaulus viviparus in dairy cattle in Flanders (Belgium).

    PubMed

    Bennema, S; Vercruysse, J; Claerebout, E; Schnieder, T; Strube, C; Ducheyne, E; Hendrickx, G; Charlier, J

    2009-10-28

    Fasciola hepatica, Ostertagia ostertagi and Dictyocaulus viviparus are helminth parasites with a wide distribution and an important economic impact in cattle in temperate climates. This paper describes the spatial distribution of F. hepatica, O. ostertagi and D. viviparus in dairy herds in Flanders (Belgium). One thousand eight hundred herds were selected at random from the Flemish dairy population (n=7002), stratified on community level to obtain a sample representative for the entire study area. From each herd, a bulk milk sample collected in autumn 2006 was analysed with previously described antibody-ELISAs in order to identify herds where the parasite infection level is likely to cause production loss (F. hepatica and O. ostertagi) (defined as economic infections) or where patent infections have been present over the past grazing season (D. viviparus). The herd prevalence of economic infections with F. hepatica and O. ostertagi was 37.3% (95% Confidence Interval (CI): 35.1-39.7) and 59.1% (95%CI: 56.8-61.4), respectively. The herd prevalence of D. viviparus was 19.6% (95%CI: 17.7-21.6). On 28.9% (CI 26.8-31.3) of the herds, low levels of infection were observed for all three of the helminths. The presence of clustering of (economic) infections was studied using Moran's I, whereas the location and size of the clusters were studied using the spatial scan statistic, the Local Indicator of Spatial Association and Kernel density plotting. A marked clustering in the spatial distribution of F. hepatica and a mild clustering in the spatial distribution of O. ostertagi were observed. D. viviparus infections were spread evenly over Flanders. Knowledge of locations of high risk areas can lead to increased awareness and may be the start of the development of regionally adapted control measures.

  1. Bayesian spatio-temporal modelling of national milk-recording data of seasonal-calving New Zealand dairy herds.

    PubMed

    Clements, A C A; Pfeiffer, D U; Hayes, D

    2005-10-12

    A spatio-temporal analysis was undertaken with the aim of identifying the dynamics of herd mean individual cow SCCs (MICSCC) in seasonally calving New Zealand dairy herds. Two datasets were extracted from the Livestock Improvement Corporation's extensive national dairy recording database: (1) milk-recording data aggregated at the herd-level and (2) sales questionnaire data containing information on the size, location and infrastructure of each farm. A Bayesian spatio-temporal modelling approach was applied to the analysis. The data were aggregated by 10 km(2) grid cells and linear regression models were developed with spatially structured and unstructured random effects, a linear temporal trend random effect and spatial-temporal interactions for log-transformed median MISCC (ln(median MISCC)). Significant associations were found between ln(median MISCC) and milk yield, milk fat, milk protein, farm area and number of cups in the dairy. This led us to suggest that SCCs should be adjusted for volume and constituents prior to determining a threshold MISCC for identification of subclinical mastitis (SCM) problem herds. Part, or all, of the temporal trend in MISCC in the spatio-temporal model was accounted for by inclusion of yield and milk constituents as independent variables. This supports the hypothesis of a dilution effect with potential consequences for misdiagnosis of SCM, particularly in late lactation. Unmeasured covariates were similarly likely to be spatially structured and unstructured. PMID:16107283

  2. Effectiveness of genetic evaluations in predicting daughter performance in individual herds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Response to genetic selection has been demonstrated nationally for US dairy cattle, but producers are more likely to appreciate the value of genetic selection if trends within their own herds can be shown. Responses from 2004 through 2008 in individual herds by Holstein and Jersey cows were document...

  3. Integrating genomic selection into dairy cattle breeding programmes: a review.

    PubMed

    Bouquet, A; Juga, J

    2013-05-01

    Extensive genetic progress has been achieved in dairy cattle populations on many traits of economic importance because of efficient breeding programmes. Success of these programmes has relied on progeny testing of the best young males to accurately assess their genetic merit and hence their potential for breeding. Over the last few years, the integration of dense genomic information into statistical tools used to make selection decisions, commonly referred to as genomic selection, has enabled gains in predicting accuracy of breeding values for young animals without own performance. The possibility to select animals at an early stage allows defining new breeding strategies aimed at boosting genetic progress while reducing costs. The first objective of this article was to review methods used to model and optimize breeding schemes integrating genomic selection and to discuss their relative advantages and limitations. The second objective was to summarize the main results and perspectives on the use of genomic selection in practical breeding schemes, on the basis of the example of dairy cattle populations. Two main designs of breeding programmes integrating genomic selection were studied in dairy cattle. Genomic selection can be used either for pre-selecting males to be progeny tested or for selecting males to be used as active sires in the population. The first option produces moderate genetic gains without changing the structure of breeding programmes. The second option leads to large genetic gains, up to double those of conventional schemes because of a major reduction in the mean generation interval, but it requires greater changes in breeding programme structure. The literature suggests that genomic selection becomes more attractive when it is coupled with embryo transfer technologies to further increase selection intensity on the dam-to-sire pathway. The use of genomic information also offers new opportunities to improve preservation of genetic variation. However

  4. Short communication: Factors affecting vitamin B12 concentration in milk of commercial dairy herds: An exploratory study.

    PubMed

    Duplessis, M; Pellerin, D; Cue, R I; Girard, C L

    2016-06-01

    Only bacteria can synthesize vitamin B12, and this requires adequate Co supply. The natural source of vitamin B12 in human diets comes from animal products, especially those from ruminants. This study aimed to describe variability regarding vitamin B12 concentration in milk among and within commercial dairy herds in early lactation. A secondary objective was to explore potential causes for this variability such as genetic variation and diet characteristics. In total, 399 dairy cows (135 primiparous and 264 multiparous; 386 Holstein and 13 Jersey cows) in 15 commercial herds were involved. Milk samples were taken at 27.4±4.1 and 55.4±4.1d in milk. Neither parity (primiparous vs. multiparous) nor sampling time affected milk concentrations of vitamin B12. Nevertheless, vitamin B12 concentration in milk was highly variable among and within dairy herds. The lowest vitamin B12 concentration in milk of cows was observed in the Jersey herd. Among herds, vitamin B12 concentration in milk ranged from 2,309 to 3,878 pg/mL; one glass (250mL) of milk from those herds would provide between 23 and 40% of the vitamin B12 recommended daily allowance. Among individual cows, however, this provision varied between 16 and 57% of the recommendation. In spite of the limited size of the studied population, the heritability value was 0.23, suggesting that genetic selection could modify milk vitamin B12 concentration. We observed a positive relationship between milk vitamin B12 concentration and dietary acid detergent fiber content and a negative relationship between milk concentration of vitamin B12 and dietary crude protein content. PMID:27040783

  5. Short communication: Factors affecting vitamin B12 concentration in milk of commercial dairy herds: An exploratory study.

    PubMed

    Duplessis, M; Pellerin, D; Cue, R I; Girard, C L

    2016-06-01

    Only bacteria can synthesize vitamin B12, and this requires adequate Co supply. The natural source of vitamin B12 in human diets comes from animal products, especially those from ruminants. This study aimed to describe variability regarding vitamin B12 concentration in milk among and within commercial dairy herds in early lactation. A secondary objective was to explore potential causes for this variability such as genetic variation and diet characteristics. In total, 399 dairy cows (135 primiparous and 264 multiparous; 386 Holstein and 13 Jersey cows) in 15 commercial herds were involved. Milk samples were taken at 27.4±4.1 and 55.4±4.1d in milk. Neither parity (primiparous vs. multiparous) nor sampling time affected milk concentrations of vitamin B12. Nevertheless, vitamin B12 concentration in milk was highly variable among and within dairy herds. The lowest vitamin B12 concentration in milk of cows was observed in the Jersey herd. Among herds, vitamin B12 concentration in milk ranged from 2,309 to 3,878 pg/mL; one glass (250mL) of milk from those herds would provide between 23 and 40% of the vitamin B12 recommended daily allowance. Among individual cows, however, this provision varied between 16 and 57% of the recommendation. In spite of the limited size of the studied population, the heritability value was 0.23, suggesting that genetic selection could modify milk vitamin B12 concentration. We observed a positive relationship between milk vitamin B12 concentration and dietary acid detergent fiber content and a negative relationship between milk concentration of vitamin B12 and dietary crude protein content.

  6. Prevalence of brucellosis in dairy cattle from the main dairy farming regions of Eritrea.

    PubMed

    Scacchia, Massimo; Di Provvido, Andrea; Ippoliti, Carla; Kefle, Uqbazghi; Sebhatu, Tesfaalem T; D'Angelo, Annarita; De Massis, Fabrizio

    2013-04-23

    In order to get a reliable estimate of brucellosis prevalence in Eritrean dairy cattle, a cross-sectional study was carried out in 2009. The survey considered the sub-population of dairy cattle reared in modern small- and medium-sized farms. Samples were screened with the Rose Bengal test (RBT) and positive cases were confirmed with the complement fixation test (CFT). A total of 2.77%(417/15 049; Credibility Interval CI: 2.52% - 3.05%) of the animals tested in this study were positive for antibodies to Brucellaspecies, with a variable and generally low distribution of positive animals at regional level. The highest seroprevalence was found in the Maekel region (5.15%; CI: 4.58% - 5.80%), followed by the Debub (1.99%; CI: 1.59% - 2.50%) and Gash-Barka (1.71%; CI: 1.34% - 2.20%) regions. Seroprevalence at sub-regional levels was also generally low, except for two sub-regions of Debub and the sub-region Haicota from the Gash-Barka region. Seroprevalence was high and more uniformly distributed in the Maekel region, namely in the Asmara, Berik and Serejeka sub-regions. Considering the overall low brucellosis prevalence in the country, as identified by the present study, a brucellosis eradication programme for dairy farms using a test-and-slaughter policy would be possible. However, to encourage the voluntary participation of farmers to the programme and to raise their awareness of the risks related to the disease for animals and humans, an extensive public awareness campaign should be carefully considered, as well as strict and mandatory dairy movement control.

  7. Imbedding HACCP principles in dairy herd health and production management: case report on calf rearing

    PubMed Central

    2008-01-01

    Driven by consumer demands, European legislation has suggested the use of HACCP (Hazard Analysis Critical Control Point) as the quality risk management programme for the whole dairy chain. Until now, an exception has been made for primary producers, but as regulations evolve, on-farm HACCP-like programmes should be ready to assure food safety as well as animal health and animal welfare. In our field experiment, the HACCP-concept was used to combine both optimal farm management and formalisation of quality assurance in an on-farm situation in the Netherlands. The process of young stock rearing was chosen, since its importance for the future of the farm is often underestimated. Hazards and their associated risk factors can be controlled within the farm-specific standards and tolerances, as targets can be controlled by corrective measures and by implementation of farm-specific worksheets. The veterinarian is pivotal for the facility-based HACCP team, since he/she has knowledge about on-farm risk assessment and relations between clinical pathology, feed and farm management. The HACCP concept in combination with veterinary herd health and production management programmes offers a promising approach to optimise on-farm production processes (i.e., young stock rearing) in addition to a structural approach for quality risk management on dairy farms. PMID:21851722

  8. Using routinely recorded herd data to predict and benchmark herd and cow health status

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Genetic improvement of dairy cattle health using producer-recorded data is feasible. Estimates of heritability are low, indicating that genetic progress will be slow. Improvement of health traits may also be possible with the incorporation of environmental and managerial aspects into herd health pro...

  9. Factors associated with frequency of abortions recorded through Dairy Herd Improvement test plans.

    PubMed

    Norman, H D; Miller, R H; Wright, J R; Hutchison, J L; Olson, K M

    2012-07-01

    Frequency of abortions recorded through Dairy Herd Improvement (DHI) testing was summarized for cows with lactations completed from 2001 through 2009. For 8.5 million DHI lactations of cows that had recorded breeding dates and were >151 d pregnant at lactation termination, the frequency of recorded abortions was 1.31%. Effects of year, herd-year, month, and pregnancy stage at lactation termination; parity; breed; milk yield; herd size; geographic region; and state within region associated with DHI-recorded abortion were examined. Abortions recorded through DHI (minimum gestation of 152 d required) were more frequent during early gestation; least squares means (LSM) were 4.38, 3.27, 1.19, and 0.59% for 152 to 175, 176 to 200, 201 to 225, and 226 to 250 d pregnant, respectively. Frequency of DHI-recorded abortions was 1.40% for parity 1 and 1.01% for parity ≥ 8. Abortion frequency was highest from May through August (1.42 to 1.53%) and lowest from October through February (1.09 to 1.21%). Frequency of DHI-recorded abortions was higher for Holsteins (1.32%) than for Jerseys (1.10%) and other breeds (1.27%). Little relationship was found between DHI-recorded abortions and herd size. Abortion frequencies for effects should be considered to be underestimated because many abortions, especially those caused by genetic recessives, go undetected. Therefore, various nonreturn rates (NRR; 60, 80, …, 200 d) were calculated to document pregnancy loss confirmed by the absence of homozygotes in the population. Breeding records for April 2011 US Department of Agriculture sire conception rate evaluations were analyzed with the model used for official evaluations with the addition of an interaction between carrier status of the service sire (embryo's sire) and cow sire (embryo's maternal grandsire). Over 13 million matings were examined using various NRR for Holstein lethal recessive traits (brachyspina and complex vertebral malformation) and undesirable recessive haplotypes (HH1

  10. Neospora caninum in Estonian dairy herds in relation to herd size, reproduction parameters, bovine virus diarrhoea virus, and bovine herpes virus 1.

    PubMed

    Lassen, Brian; Orro, Toomas; Aleksejev, Annely; Raaperi, Kerli; Järvis, Toivo; Viltrop, Arvo

    2012-11-23

    Cows infected with the tissue parasite Neospora caninum (Nc) are more likely to abort or give birth to calves with neurological disorders. The known infection routes are transplacentally and by consumption of oocysts shed by the definitive host, the dog. It has been hypothesised, that dormant stages of persistent Nc infection may be reactivated by immunosuppression mechanisms such as pathogenic invasions as bovine herpes virus 1 (BHV1) and bovine virus diarrhoea virus (BVDV). The study was set to give the first prevalence data on Nc from Estonian dairy herds in both animal as well as herd level. In addition, association between herd size and Nc, and association of Nc with abortion incidence (Ab), stillbirth incidence (Sb), insemination index (II), and calving interval (CaI) in the presence of BHV1 and BVDV was studied. Blood samples from 1973 animals from 100 herds were collected in 2006-2008, and 320 bulk tank milk (BTM) samples were collected in 2007. Antibodies against Nc was found in 2.5 ± 0.4% (95% CI) of the animals and at least one positive animal was found in 37.0 ± 4.7% (95% CI) of the herds. In addition, Nc antibodies were detected in 16.3 ± 2.0% (95% CI) of the tested BTM. Large herds (≥ 200 animals) were less likely to have seropositive animals for Nc. Logistic regression models showed that herds with more than one animal seropositive for Nc had significantly higher odds ratio of abortion incidence (OR: 11.92, 1.18-120.18 95% CI, p=0.036) and tendency of having more stillbirths (OR: 5.52, 0.87-35.02 95% CI, p=0.07). On the other hand one Nc seropostive cow in the herd was associated with lower odds ratio (OR: 0.22, 0.05-0.91 95% CI, p=0.04) of higher calving intervals. Estonian prevalence results reflect observations in the region. No evidence was found of the pathogens were affecting fertility variables through interactions but independently BHV1 and Nc had an impact on the abortion.

  11. Spontaneous reduction of advanced twin embryos: its occurrence and clinical relevance in dairy cattle.

    PubMed

    López-Gatius, F; Hunter, R H F

    2005-01-01

    Twin pregnancies represent a management problem in dairy cattle since the risk of pregnancy loss increases, and the profitability of the herd diminishes drastically as the frequency of twin births increases. The aim of this study was to monitor the development of 211 twin pregnancies in high producing dairy cows in order to determine the best time for an embryo reduction approach. Pregnancy was diagnosed by transrectal ultrasonography between 36 and 42 days after insemination. Animals were then subjected to weekly ultrasound examination until Day 90 of gestation or until pregnancy loss. Viability was determined by monitoring the embryonic/fetal heartbeat until Day 50 of pregnancy, and then by heartbeat or fetal movement detection. Eighty-six cows (40.8%) bore bilateral and 125 (59.2%) unilateral twin pregnancies. Embryo death was registered in one of the two embryos in 35 cows (16.6%), 33 of them at pregnancy diagnosis. Pregnancy loss occurred in 22 of these cows between 1 and 4 weeks later. Thus, 13 (6.2% of the total animals) cows, carrying one dead of the two embryos, maintained gestation. Total pregnancy loss before Day 90 of pregnancy (mean 69 +/- 14 days) was registered in 51 (24.2%) cows: 7 (8%) of bilateral pregnancies and 44 (35.2%) of unilateral pregnancies, and it was higher (P = 0.0001) for both right (32.4%, 24/74) and left (39.2%, 20/51) unilateral than for bilateral (8.1%, 7/86) twin pregnancies. The single embryo death rate was significantly (P = 0.02) lower for cows with bilateral twins (9.3%, 8/86) than for total cows with unilateral twins (21.6%, 27/125). By way of overall conclusion, embryo reduction can occur in dairy cattle, and the practical perspective remains that most embryonic mortality in twins (one of the two embryos) occurs around Days 35-40 of gestation, the period when pregnancy diagnosis is generally performed and when embryo reduction could be tried.

  12. Association between thermal environment and Salmonella in fecal samples from dairy cattle in midwestern United States.

    PubMed

    Likavec, Tasha; Pires, Alda F A; Funk, Julie A

    2016-07-01

    The objective of this study was to describe the association between thermal measures in the barn environment (pen temperature and humidity) and fecal shedding of Salmonella in dairy cattle. A repeated cross-sectional study was conducted within a commercial dairy herd located in the midwestern United States. Five pooled fecal samples were collected monthly from each pen for 9 mo and submitted for microbiological culture. Negative binomial regression methods were used to test the association [incidence rate ratio (IRR)] between Salmonella pen status (the count of Salmonella-positive pools) and thermal environmental parameters [average temperature and temperature humidity index (THI)] for 3 time periods (48 h, 72 h, and 1 wk) before fecal sampling. Salmonella was cultured from 10.8% [39/360; 95% confidence interval (CI): 7.8% to 14.5%] of pooled samples. The highest proportion of positive pools occurred in August. The IRR ranged from 1.26 (95% CI: 1.15 to 1.39, THI 1 wk) to 4.5 (95% CI: 2.13 to 9.51, heat exposure 1 wk) across all thermal parameters and lag time periods measured. For example, the incidence rate of Salmonella-positive pools increased by 54% for every 5°C increment in average temperature (IRR = 1.54; 95% CI: 1.29 to 1.85) and 29% for every 5-unit increase in THI (IRR = 1.29; 95% CI: 1.16 to 1.42) during the 72 h before sampling. The incidence rate ratio for pens exposed to higher temperatures (> 25°C) was 4.5 times (95% CI: 2.13 to 9.51) the incidence rate ratio for pens exposed to temperatures < 25°C in the 72 h before sampling. Likewise, the incidence rate ratio for pens exposed to THI > 70 was 4.23 times greater (95% CI: 2.1 to 8.28) than when the THI was < 70 in the 72 h before sampling. An association was found between the thermal environment and Salmonella shedding in dairy cattle. Further research is warranted in order to fully understand the component risks associated with the summer season and increased Salmonella shedding. PMID:27408330

  13. Occurrence and molecular characterization of Cryptosporidium spp. and Enterocytozoon bieneusi in dairy cattle, beef cattle and water buffaloes in China.

    PubMed

    Ma, Jingbo; Li, Pei; Zhao, Xiaoping; Xu, Hailing; Wu, Wenxian; Wang, Yuanfei; Guo, Yaqiong; Wang, Lin; Feng, Yaoyu; Xiao, Lihua

    2015-01-30

    Cryptosporidium spp. and Enterocytozoon bieneusi are important protists in a wide range of vertebrate hosts, causing diarrheal diseases. Cattle are considered potential reservoirs of Cryptosporidium infection in humans, although their role in the transmission of E. bieneusi is not clear. In the present work, 793 fecal specimens from dairy cattle, native beef cattle, and water buffaloes on 11 farms in China were examined for the presence of Cryptosporidium spp. and E. bieneusi using nested PCR targeting the small subunit (SSU) rRNA gene of Cryptosporidium spp. and the internal transcribed spacer (ITS) of E. bieneusi. For Cryptosporidium, 144/446 (32.3%) dairy cattle, 44/166 (26.5%) beef cattle, and 43/181 (23.8%) water buffaloes were PCR-positive. Sequence analysis was successful for 213 of the 231 Cryptosporidium-positive isolates; among them 94 had Cryptosporidium andersoni, 61 had Cryptosporidium bovis, 54 had Cryptosporidium ryanae, 2 had a Cryptosporidium suis-like genotype, and 2 had mixed infections of C. bovis and C. ryanae. In dairy and beef cattle, C. andersoni and C. bovis were the most common species, whereas C. ryanae was the dominant species in water buffaloes. The latter species produced SSU rRNA sequences different between cattle and water buffaloes. For E. bieneusi, the infection rate of E. bieneusi in dairy cattle, beef cattle and water buffaloes was 4.9%, 5.4% and 2.2%, respectively. All 35 E. bieneusi-positive specimens were successfully sequenced, revealing the presence of four genotypes: three Group 2 genotypes previously reported in cattle as well as humans (I, J and BEB4) and one Group 1 genotype recently reported in yaks (CHN11). Genotypes I and J were the most common genotypes in dairy and beef cattle, while genotype CHN11 was the only genotype seen in water buffaloes. Thus, the distribution of Cryptosporidium spp. and E. bieneusi in water buffaloes might be different from in dairy and beef cattle in China. These findings indicate that some

  14. Tuberculosis in cattle herds are sentinels for Mycobacterium bovis infection in European badgers (Meles meles): the Irish Greenfield Study.

    PubMed

    Murphy, D; Gormley, E; Collins, D M; McGrath, G; Sovsic, E; Costello, E; Corner, L A L

    2011-07-01

    In Ireland badgers are removed in response to tuberculosis (TB) breakdowns in cattle herds (focal culling). Prevalence studies, conducted using a detailed post mortem and bacteriological examination, showed that 36-50% of badgers were infected with Mycobacterium bovis. Focal culling forms part of the medium term national strategy for the control of bovine TB in cattle and is based on the premise that badgers in areas with herd breakdowns have a higher prevalence of infection than the badger population at large. However, the hypothesis that cattle can be used as sentinels for infection in the badger population has never been formally tested. In this study we tested the hypothesis by determining the infection prevalence in badgers in areas where there had been historically, a consistently low prevalence of infection in cattle. Low cattle TB prevalence areas were defined as those herds with ≤ 2 standard reactors in the annual round of skin testing over the preceding 5 years (Greenfield sites). Using GIS, and adjusting for variation in land use, previous culling and cattle density, 198 Greenfield sites were identified and surveyed, and 138 areas with badger setts or signs of badger activity were identified. A single badger was removed from 87 sites and all were examined using detailed post mortem and bacteriological procedures. A prevalence of M. bovis infection of 14.9% was found in the Greenfield site badgers. This prevalence was significantly lower (P<0.001) than in badgers removed during focal culling (36.6%). The results validate the use of cattle as sentinels for TB in badgers and support the medium term national strategy for the control of bovine TB. The geographic variation in M. bovis infection prevalence in the Irish badger populations will be used when devising strategies for the incorporation of badger vaccination into the long term bovine TB control programme.

  15. Metabolic profile of Japanese Black breeding cattle herds: usefulness in selection for nutrient supplementation to enhance reproductive performance and regional differences.

    PubMed

    Watanabe, Urara; Takagi, Mitsuhiro; Yamato, Osamu; Otoi, Takeshige; Tshering, Chenga; Okamoto, Koji

    2013-05-01

    The study aims were (1) to confirm the effects of nutritional improvement in prepartal and postpartal periods, monitored using the serum metabolic profile test (MPT) and reproductive performance, and (2) to clarify regional characteristics of the MPT results within our jurisdiction by using our MPT database. Experiment 1: Among 42 breeding cattle herds in our jurisdiction mainly fed home-pasture roughage, 3 experimental herds showing subnormal blood urea nitrogen (BUN) levels were selected and compared with 1 representative excellent herd. Dietary remedial measures were implemented from feed analysis in each herd. BUN concentration in all 3 herds increased significantly, and open days postpartum in 2 of the herds were significantly reduced, compared with values before dietary supplementation. Experiment 2: Thirty-seven herds within our jurisdiction were grouped into 3 categories (Area 1, 2 and 3) by location and soil condition of the herd pastureland. The MPT and reproductive performance in cows whose blood samples were collected at both prepartum (60-20 days before calving) and postpartum (30-90 days after calving) were compared among the 3 areas. Significant regional differences were found in prepartal albumin, total cholesterol, BUN, and glucose and postpartal BUN, glucose and open days (P<0.05). Overall, the MPT (especially BUN) might be useful for determining the metabolic nutritional status of breeding cattle herds, particularly those fed home-pasture roughage. Additionally, poor/unsatisfactory reproductive performance of beef breeding cattle herds probably reflects inadequate nutritional content of the diet, possibly arising from regional pastureland differences.

  16. Parasitic infections in dairy cattle around Hanoi, northern Vietnam.

    PubMed

    Geurden, T; Somers, R; Thanh, N T G; Vien, L V; Nga, V T; Giang, H H; Dorny, P; Giao, H K; Vercruysse, J

    2008-05-31

    In northern Vietnam, dairy cattle are mainly managed in small-scale farms, where animals are kept confined and feeding occurs by cut and carry methods. In the present study the occurrence of parasitic infections was examined in five provinces around Hanoi. A total of 201 farms were visited, and 334 stool and 239 blood samples were collected from calves younger than 3 months, animals between 3 and 24 months and adult cows. Furthermore, 254 milk samples were collected from lactating animals. Coproscopical examination indicated a high prevalence of nematode eggs (Cooperia spp., Haemonchus and Oesophagostomum spp.) in animals (n=176) between 3 and 24 months (66%) and in adult cows (n=90; 54%). In these age groups the prevalence of Fasciola was 28% and 39%, respectively, and for Paramphistomum the prevalence was 78% and 82%, respectively. Fifty percent of the calves younger than 3 months (n=68) were positive for Giardia, and none for Cryptosporidium. Most Giardia isolates were identified as the non-zoonotic G. duodenalis assemblage E on the beta-giardin gene. The blood samples were examined with commercially available Svanovir((R))Elisa's for the presence of Anaplasma marginale and Babesia bigemina specific antibodies, and a prevalence of 28% and 54% was found, respectively. In the milk samples Neospora caninum specific antibodies (Svanovir((R))Elisa) were detected in 30% of the lactating animals. The present study demonstrates that parasitic infections occur frequently in dairy cattle around Hanoi although animals are mainly kept confined, and indicates that further research on the economic impact of these infections is needed. PMID:18328629

  17. Association of claw disorders with claw horn colour in norwegian red cattle - a cross-sectional study of 2607 cows from 112 herds

    PubMed Central

    2011-01-01

    Claw disorders cause problems in dairy cattle all over the world. Nutrition, feeding, environment, claw trimming routines, hormonal changes related to calving and genetics are among the factors which influence the pathogenesis. The colour of the claw horn (pigmentation) has been suggested to play a role. The aim of this study was to investigate if there were any associations between the colour of the sole horn and claw disorders detected at claw trimming. Altogether, 2607 cows on 112 farms were claw trimmed once and the colour (dark, mixed or light) of the right lateral hind claw and hind claw disorders were recorded by 13 trained claw trimmers. The data were analysed using logistic regression models with logit link function, binomial distribution and herd and claw trimmer as repeated effects, with herd nested within claw trimmer. Haemorrhages of the sole (HS) and white line (HWL) were more frequently found in light than in dark claws (OR = 2.61 and 2.34, respectively). Both HS (OR = 1.43) and corkscrewed claws (OR = 1.84) were slightly more prevalent among cows which had claws with mixed colour versus dark claws. There were no significant associations of other claw disorders with claw horn colour. PMID:22085414

  18. Management practices associated with conception rate and service rate of lactating Holstein cows in large, commercial dairy herds.

    PubMed

    Schefers, J M; Weigel, K A; Rawson, C L; Zwald, N R; Cook, N B

    2010-04-01

    Data from lactating Holstein cows in herds that participate in a commercial progeny testing program were analyzed to explain management factors associated with herd-average conception and service rates on large commercial dairies. On-farm herd management software was used as the source of data related to production, reproduction, culling, and milk quality for 108 herds. Also, a survey regarding management, facilities, nutrition, and labor was completed on 86 farms. A total of 41 explanatory variables related to management factors and conditions that could affect conception and service rate were considered in this study. Models explaining conception and service rates were developed using a machine learning algorithm for constructing model trees. The most important explanatory variables associated with conception rate were the percentage of repeated inseminations between 4 and 17 d post-artificial insemination, stocking density in the breeding pen, length of the voluntary waiting period, days at pregnancy examination, and somatic cell score. The most important explanatory variables associated with service rate were the number of lactating cows per breeding technician, use of a resynchronization program, utilization of soakers in the holding area during the summer, and bunk space per cow in the breeding pen. The aforementioned models explained 35% and 40% of the observed variation in conception rate and service rate, respectively, and underline the association of herd-level management factors not strictly related to reproduction with herd reproductive performance.

  19. Temporal trends in bulk tank somatic cell count and total bacterial count in Irish dairy herds during the past decade.

    PubMed

    Berry, D P; O'Brien, B; O'Callaghan, E J; Sullivan, K O; Meaney, W J

    2006-10-01

    The objective of this study was to document temporal trends in bulk tank somatic cell count (SCC) and total bacterial counts (TBC) in Irish dairy herds during the years 1994 to 2004. Three milk processors participated in the study, providing data on 2,754,270 individual bulk tank SCC and 2,056,992 individual bulk tank TBC records from 9,113 herds. Somatic cell counts decreased during the years 1994 to 2000, followed by an annual increase thereafter of more than 2,000 cells/mL. A tendency existed for TBC to decrease over time. Across all years, bulk tank SCC were the lowest in April and highest in November; TBC were the lowest in May and highest in December. The significant seasonal pattern observed in herd SCC and TBC was an artifact of seasonal calving in Ireland. In general, herds selling more milk had lower bulk tank SCC and TBC. Herds having the highest SCC (i.e., > 450,000 cells/mL) and the lowest SCC (i.e., < or = 150,000 cells/mL) both contributed substantially to the mean SCC of the milk pool collected by the milk processors. Derived transition matrices showed that between adjacent years, herds had the greatest probability of remaining in the same annual mean SCC or TBC category.

  20. Association between interleukin 8 receptor α gene (CXCR1) and mastitis in dairy cattle

    PubMed Central

    Pawlik, Adrianna; Kapera, Magdalena; Korwin-Kossakowska, Agnieszka

    2015-01-01

    The innate immune response plays an important role in the course of bacterial infections. Innate immunity effectiveness relies on the expression of many genes, connected, among others, to the activity of neutrophils. Interleukin 8 (IL-8) receptor α, coded by the CXCR1 gene, is present on the neutrophil surface and binds pro-inflammatory IL-8 with high affinity. This is why the bovine CXCR1 gene carries a potential for use as a dairy cattle mastitis marker. To date, several studies on the CXCR1 polymorphism brought out contradictory results. The aim of this study was to analyse the association between two SNPs of the CXCR1 gene, which is potentially important for the protein function and animal phenotype for mastitis susceptibility. A total of 554 Polish Holsteins were genotyped, and 140 among them were bacteriologically tested. The differences between animals carrying different genotypes and haplotypes of CXCR1 in test day somatic cell count (SCC) and Staphylococcus aureus mastitis susceptibility were estimated. We found that test day SCC was significantly related to CXCR1+472 SNP but not to CXCR1+735 SNP. No statistically significant association between CXCR1 polymorphism and susceptibility to S. aureus mastitis was found in the studied herd. PMID:26557028

  1. Genome-Wide Diversity and Phylogeography of Mycobacterium avium subsp. paratuberculosis in Canadian Dairy Cattle.

    PubMed

    Ahlstrom, Christina; Barkema, Herman W; Stevenson, Karen; Zadoks, Ruth N; Biek, Roman; Kao, Rowland; Trewby, Hannah; Haupstein, Deb; Kelton, David F; Fecteau, Gilles; Labrecque, Olivia; Keefe, Greg P; McKenna, Shawn L B; Tahlan, Kapil; De Buck, Jeroen

    2016-01-01

    Mycobacterium avium subsp. paratuberculosis (MAP) is the causative bacterium of Johne's disease (JD) in ruminants. The control of JD in the dairy industry is challenging, but can be improved with a better understanding of the diversity and distribution of MAP subtypes. Previously established molecular typing techniques used to differentiate MAP have not been sufficiently discriminatory and/or reliable to accurately assess the population structure. In this study, the genetic diversity of 182 MAP isolates representing all Canadian provinces was compared to the known global diversity, using single nucleotide polymorphisms identified through whole genome sequencing. MAP isolates from Canada represented a subset of the known global diversity, as there were global isolates intermingled with Canadian isolates, as well as multiple global subtypes that were not found in Canada. One Type III and six "Bison type" isolates were found in Canada as well as one Type II subtype that represented 86% of all Canadian isolates. Rarefaction estimated larger subtype richness in Québec than in other Canadian provinces using a strict definition of MAP subtypes and lower subtype richness in the Atlantic region using a relaxed definition. Significant phylogeographic clustering was observed at the inter-provincial but not at the intra-provincial level, although most major clades were found in all provinces. The large number of shared subtypes among provinces suggests that cattle movement is a major driver of MAP transmission at the herd level, which is further supported by the lack of spatial clustering on an intra-provincial scale. PMID:26871723

  2. Molecular epidemiology of mastitis pathogens of dairy cattle and comparative relevance to humans.

    PubMed

    Zadoks, Ruth N; Middleton, John R; McDougall, Scott; Katholm, Jorgen; Schukken, Ynte H

    2011-12-01

    Mastitis, inflammation of the mammary gland, can be caused by a wide range of organisms, including gram-negative and gram-positive bacteria, mycoplasmas and algae. Many microbial species that are common causes of bovine mastitis, such as Escherichia coli, Klebsiella pneumoniae, Streptococcus agalactiae and Staphylococcus aureus also occur as commensals or pathogens of humans whereas other causative species, such as Streptococcus uberis, Streptococcus dysgalactiae subsp. dysgalactiae or Staphylococcus chromogenes, are almost exclusively found in animals. A wide range of molecular typing methods have been used in the past two decades to investigate the epidemiology of bovine mastitis at the subspecies level. These include comparative typing methods that are based on electrophoretic banding patterns, library typing methods that are based on the sequence of selected genes, virulence gene arrays and whole genome sequencing projects. The strain distribution of mastitis pathogens has been investigated within individual animals and across animals, herds, countries and host species, with consideration of the mammary gland, other animal or human body sites, and environmental sources. Molecular epidemiological studies have contributed considerably to our understanding of sources, transmission routes, and prognosis for many bovine mastitis pathogens and to our understanding of mechanisms of host-adaptation and disease causation. In this review, we summarize knowledge gleaned from two decades of molecular epidemiological studies of mastitis pathogens in dairy cattle and discuss aspects of comparative relevance to human medicine.

  3. Molecular epidemiology of mastitis pathogens of dairy cattle and comparative relevance to humans.

    PubMed

    Zadoks, Ruth N; Middleton, John R; McDougall, Scott; Katholm, Jorgen; Schukken, Ynte H

    2011-12-01

    Mastitis, inflammation of the mammary gland, can be caused by a wide range of organisms, including gram-negative and gram-positive bacteria, mycoplasmas and algae. Many microbial species that are common causes of bovine mastitis, such as Escherichia coli, Klebsiella pneumoniae, Streptococcus agalactiae and Staphylococcus aureus also occur as commensals or pathogens of humans whereas other causative species, such as Streptococcus uberis, Streptococcus dysgalactiae subsp. dysgalactiae or Staphylococcus chromogenes, are almost exclusively found in animals. A wide range of molecular typing methods have been used in the past two decades to investigate the epidemiology of bovine mastitis at the subspecies level. These include comparative typing methods that are based on electrophoretic banding patterns, library typing methods that are based on the sequence of selected genes, virulence gene arrays and whole genome sequencing projects. The strain distribution of mastitis pathogens has been investigated within individual animals and across animals, herds, countries and host species, with consideration of the mammary gland, other animal or human body sites, and environmental sources. Molecular epidemiological studies have contributed considerably to our understanding of sources, transmission routes, and prognosis for many bovine mastitis pathogens and to our understanding of mechanisms of host-adaptation and disease causation. In this review, we summarize knowledge gleaned from two decades of molecular epidemiological studies of mastitis pathogens in dairy cattle and discuss aspects of comparative relevance to human medicine. PMID:21968538

  4. Experimental results of the use of flavofosfolipol in dairy cattle.

    PubMed

    Ruffo, G; Valerani, L

    1977-01-01

    In a field trial carried out on a farm with about 100 dairy cows, half of the animals were treated orally with 45 mg flavofosfolipol per animal daily for 370 days, while the other half were untreated controls. The administration of the flavofosfolipol did not produce any residues in the milk. Body functions and fertility were not affected. Milk production was increased, although not with statistical significance. The qualitative characteristics of the milk and its cheese-making properties were normal. The casein content was increased by 6.58% over that of the controls, and thus was statistically significant. There was a statistically significant decrease in the mean cell content of the milk. The high negative correlation between the casein level and the cell content of the milk suggests that an improvement in the function of the mammary parenchyma could be responsible for the higher casein content. This improvement in function could also be due to a favourable effect of the antibiotic, still to be clarified, on the ruminal microflora. In economic terms the use of flavofosfolipol in dairy cattle seems to be of considerable interest.

  5. Herd- and individual-level prevalences of and risk factors for Salmonella spp. fecal shedding in dairy farms in Al-Dhulail Valley, Jordan.

    PubMed

    Tarazi, Yaser H; Abo-Shehada, Mahmoud N

    2015-10-01

    Salmonellosis is an important disease frequently associated with diarrhea in calves. From January to September 2009, a cross-sectional study involving 91 dairy farms was conducted to determine the prevalence of Salmonella spp. infection in cattle in Al-Dhulail Valley, Jordan. A total of 910 calve and cow fecal samples were collected. Information on farm management practices was obtained through personal interviews using a standardized questionnaire and was tested as risk factors for Salmonella spp. positivity in farms by using logistic regression analysis. Standard conventional methods for Salmonella isolation and serotyping were used, and the disk agar diffusion test was used for antimicrobial testing. The herd-level prevalence of Salmonella spp. in calves, cows, and dairy farms was 12, 12, and 23 %, respectively, and the individual-level prevalence was 4 % for calves, cows, and dairy farms. Forty-six percent of the dairy farms had calf diarrhea, and 4 % had cow diarrhea. Seven (17 %) of the 42 farms with calf diarrhea had Salmonella. However, only 7 % (95 % CI: 4, 10) of the 221 diarrheic and 1 % (95 % CI: 0.2, 4) of the 234 of non-diarrheic calves had Salmonella. A total of 33 Salmonella isolates were obtained from the fecal samples: 12 isolates were Salmonella typhimurium, 6 were Salmonella montevideo, 6 were Salmonella anatum, 2 were Salmonella enteritidis, and 7 isolates were not serotyped. All isolates were susceptible to ciprofloxacin, trimethoprim-sulfamethoxazole, gentamycin, neomycin, colisitin, and amoxicillin at 100, 91, 85, 79, 79, and 70 %, respectively. Out of the 11 variables/categories, the frequency of cleaning every 2 months or more was associated with high odds of infection among calves (OR = 5.6) and farms (OR = 7.0).

  6. Environmental and behavioural factors affecting the prevalence of foot lameness in New Zealand dairy herds - a case-control study.

    PubMed

    Chesterton, R N; Pfeiffer, D U; Morris, R S; Tanner, C M

    1989-12-01

    A case-control study of environmental and behavioural factors influencing foot lameness was undertaken on 62 dairy herds comprising an average of 185 milking cows in Taranaki, New Zealand. Thirty two case herds were identified as having had at least 10 per cent of the cows lame during the milking season in which the herd was studied, and thirty control herds were selected on the basis that no more than 3 per cent of cows in these herds had been lame per year for at least two years immediately prior to investigation. Each herd was visited at both a morning and an afternoon milking, and 58 risk factors were measured between the time the farmer began to assemble the cows for milking and the completion of milking. Comparison of single variables between case and control herds identified 24 which showed differences (p<0.10). These variables were then subjected to stepwise multivariate logistic regression, and statistically significant variables in this analysis were used to create a tentative path diagram of possible causal web relationships between the various risk factors and the outcome variable, the lameness prevalence level. Information from a review of the published literature was used to include further variables to the 24 into the initial (or null hypothesis) path model. Logistic path analysis was then used to eliminate non-significant paths from the diagram, leaving 19 arrows joining 13 variables in the final path diagram, compared with 33 joining 20 variables in the initial version. The most influential variables in explaining variation between case and control herds were the average level of maintenance of the track and the degree of patience shown by the farmer in bringing the cows in for milking. Overall, factors associated with the movement of animals to the milking shed explained 40 per cent of the variation (deviance) with regard to the lameness prevalence level. Risk factors associated with characteristics of the milking process explain 24 per cent, and

  7. Evaluating an intervention to reduce lameness in dairy cattle.

    PubMed

    Main, D C J; Leach, K A; Barker, Z E; Sedgwick, A K; Maggs, C M; Bell, N J; Whay, H R

    2012-06-01

    Lameness in dairy cattle remains a significant welfare concern for the UK dairy industry. Farms were recruited into a 3-yr study evaluating novel intervention approaches designed to encourage farmers to implement husbandry changes targeted toward reducing lameness. All farms completing the study were visited at least annually and received either monitoring only (MO, n=72) or monitoring and additional support (MS, n = 117) from the research team. The additional support included traditional technical advice on farm-specific solutions, facilitation techniques to encourage farmer participation, and application of social marketing principles to promote implementation of change. Lameness prevalence was lower in the MO (27.0 ± 1.94 SEM) and MS (21.4 ± 1.28) farms at the final visit compared with the same MO (38.9 ± 2.06) and MS (33.3 ± 1.76) farms on the initial visit. After accounting for initial lameness, intervention group status, and year of visit within a multilevel model, we observed an interaction between year and provision of support, with the reduction in lameness over time being greater in the MS group compared with the MO group. Farms in the MS group made a greater number of changes to their husbandry practices over the duration of the project (8.2 ± 0.39) compared with those farms in the MO group (6.5 ± 0.54). Because the lameness prevalence was lower in the MS group than the MO group at the start of the study, the contribution of the additional support was difficult to define. Lameness can be reduced on UK dairy farms although further work is needed to identify the optimum approaches. PMID:22612932

  8. High prevalence of fasciolosis and evaluation of drug efficacy against Fasciola hepatica in dairy cattle in the Maffra and Bairnsdale districts of Gippsland, Victoria, Australia.

    PubMed

    Elliott, T P; Kelley, J M; Rawlin, G; Spithill, T W

    2015-04-15

    Liver fluke (Fasciola hepatica) is a common parasite amongst grazing livestock in the south-eastern region of Australia and is responsible for significant production losses in the beef and dairy industries. Gippsland in Victoria is a major region for dairy production but no fluke prevalence data in livestock has been obtained in this region since the late 1970s prior to the introduction of Triclabendazole (TCBZ). TCBZ resistance is also now widespread in cattle in south east Australia. In this study, we evaluated the prevalence and intensity of liver fluke infections in dairy cattle in Gippsland and assessed the efficacy of TCBZ and other drenches against F. hepatica on one farm. We obtained 30 individual faecal samples from each of 15 different farms and, using the liver fluke coproantigen ELISA, tested bulk faecal samples pooled from each farm. Any farm that returned a positive bulk sample had all of the samples tested individually to assess the intra-herd prevalence. One farm in the Maffra district also had a coproantigen reduction test and faecal egg count reduction test to assess the efficacy of TCBZ, Clorsulon (CLOR) and Oxyclozanide (OXY). The coproantigen ELISA proved to be a highly sensitive test for liver fluke with a high correlation (R(2)=0.8849) observed between ELISA data from bulk samples and individual samples, suggesting that future larger scale screening on farms for fasciolosis could use the bulk analysis technique. The ELISA data revealed that animals on six of the 15 farms were infected with F. hepatica and the herd prevalence of the infected herds ranged from 47 to 100% (mean 81%) which exceeds the prevalence value for production losses of 25%. The intensity of fluke infection in cattle varied considerably both within and between herds with a proportion of animals exhibiting a positive control value in the coproantigen ELISA of 50-88%. We also confirmed that TCBZ resistance was present on one farm but that CLOR or OXY can be used to remove the

  9. Comparison of whole genome sequencing typing results and epidemiological contact information from outbreaks of Salmonella Dublin in Swedish cattle herds

    PubMed Central

    Ågren, Estelle C. C.; Wahlström, Helene; Vesterlund-Carlson, Catrin; Lahti, Elina; Melin, Lennart; Söderlund, Robert

    2016-01-01

    Background Whole genome sequencing (WGS) is becoming a routine tool for infectious disease outbreak investigations. The Swedish situation provides an excellent opportunity to test the usefulness of WGS for investigation of outbreaks with Salmonella Dublin (S. Dublin) as epidemiological investigations are always performed when Salmonella is detected in livestock production, and index isolates from all detected herds are stored and therefore available for analysis. This study was performed to evaluate WGS as a tool in forward and backward tracings from herds infected with S. Dublin. Material and methods In this study, 28 isolates from 26 cattle herds were analysed and the WGS results were compared with results from the epidemiological investigations, for example, information on contacts between herds. The isolates originated from herds in three different outbreaks separated geographically and to some extent also in time, and from the only region in Sweden where S. Dublin is endemic (Öland). Results The WGS results of isolates from the three non-endemic regions were reliably separated from each other and from the endemic isolates. Within the outbreaks, herds with known epidemiological contacts generally showed smaller differences between isolates as compared to when there were no known epidemiological contacts. Conclusion The results indicate that WGS can provide valuable supplemental information in S. Dublin outbreak investigations. The resolution of the WGS was sufficient to distinguish isolates from the different outbreaks and provided additional information to the investigations within an outbreak. PMID:27396609

  10. The marketing of herd health and production management services on Dutch dairy farms: perceptions of dairy farmers and their veterinary surgeons.

    PubMed

    Lievaart, Jj; Noordhuizen, Jptm; Buckley, D; Van Winden, Scl

    2008-01-01

    A questionnaire-based survey on veterinary herd health and production management services was conducted on 194 specialist dairy veterinarians and 466 dairy farmers. The farmers were randomly selected from greater than 6,000 farmer clients of the surveyed veterinarians. This paper reports these survey findings and the findings of an earlier survey conducted among the veterinarians. The survey included questions on the attributes of the service itself, the practitioners delivering the service, reasons for participation and the expected future of herd health and production management services. Reasons farmers participated in herd health and production management programmes included; access to routine screening of their herd; increasing profits; and receiving regular veterinary advice or solutions to remedy existing problems. Advantages of participation named included: good management support; higher profits; structural solutions to problems; and being better informed. Differences between farming styles were observed, pointing to the different needs and goals of farming styles. Farmers cited high costs and the time investment required as major disadvantages. The proportion of farmers citing these reasons was lower than expected by the veterinarians. In the future, preventive healthcare will be the main reason of farmers to participate. Farmers who are not using the service can potentially be encouraged to engage the services after gaining increased insight into the herd health and management service structure, the planning of activities, the cost-benefit of the service, veterinary surgeons being more co-operative with other farm advisors and veterinarians being more willing to pay attention to quality issues on the dairy farm. PMID:21851703

  11. The marketing of herd health and production management services on Dutch dairy farms: perceptions of dairy farmers and their veterinary surgeons

    PubMed Central

    2008-01-01

    A questionnaire-based survey on veterinary herd health and production management services was conducted on 194 specialist dairy veterinarians and 466 dairy farmers. The farmers were randomly selected from greater than 6,000 farmer clients of the surveyed veterinarians. This paper reports these survey findings and the findings of an earlier survey conducted among the veterinarians. The survey included questions on the attributes of the service itself, the practitioners delivering the service, reasons for participation and the expected future of herd health and production management services. Reasons farmers participated in herd health and production management programmes included; access to routine screening of their herd; increasing profits; and receiving regular veterinary advice or solutions to remedy existing problems. Advantages of participation named included: good management support; higher profits; structural solutions to problems; and being better informed. Differences between farming styles were observed, pointing to the different needs and goals of farming styles. Farmers cited high costs and the time investment required as major disadvantages. The proportion of farmers citing these reasons was lower than expected by the veterinarians. In the future, preventive healthcare will be the main reason of farmers to participate. Farmers who are not using the service can potentially be encouraged to engage the services after gaining increased insight into the herd health and management service structure, the planning of activities, the cost-benefit of the service, veterinary surgeons being more co-operative with other farm advisors and veterinarians being more willing to pay attention to quality issues on the dairy farm. PMID:21851703

  12. Efficacy of salicylic acid in the treatment of digital dermatitis in dairy cattle.

    PubMed

    Schultz, N; Capion, N

    2013-11-01

    Digital dermatitis (DD) is one of the most important causes of lameness in dairy cattle worldwide. The objective of this study was to evaluate the efficacy of salicylic acid in the treatment of the disease. A total of 201 DD lesions from 173 cows from four commercial dairy herds were evaluated at day 0 during routine hoof trimming and were allocated into two groups, namely, a control group given chlortetracycline spray, and a treatment group given 10 g of salicylic acid powder applied topically within a bandage. Pain, lesion size and clinical appearance (scored M0 to M4) were evaluated on days 3, 14 and 34 post-treatment. A change to M0 was defined as healing, while changes of M2 or M4 to M1 or M3 were classified as clinical improvements. Healing rates did not differ significantly between treatment groups at days 3 and 14. By day 34 the healing rate was fivefold better (P=0.01) for the treatment vs. the control group, with healing rates of 13.6% and 3.1%, respectively. By day 3, the rate of improvement was 2.5-fold better (P=0.02) for the controls. By day 34 the overall positive effect (i.e. healing and improvement) was 1.75-fold better (P=0.05) for the treatment group. Lesions from the control group were 2.2 times more likely (P=0.09) to have a pain score equal to 2 by day 14. The proportion of lesions getting smaller by days 14 and 34 was 2.5 times higher (P<0.08) for the treatment vs. the control group. The findings suggest salicylic acid should be considered as an alternative to chlortetracycline for the treatment of DD as it appears more efficacious and would assist in reducing antibiotic use.

  13. Heritability of rectal temperature and genetic correlations with production and reproduction traits in dairy cattle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Heat stress affects production and reproduction in dairy cattle. Genetic selection for body temperature might help to decrease the effects of heat stress on those traits. Objectives of the current study were a) to estimate genetic parameters of rectal temperature in dairy cows under heat stress cond...

  14. Seasonal variation in the prevalence and molecular epidemiology of Cryptosporidium infection in dairy cattle in the New York City Watershed.

    PubMed

    Szonyi, Barbara; Bordonaro, Rebecca; Wade, Susan E; Mohammed, Hussni O

    2010-07-01

    We conducted cross-sectional studies in the New York City Watershed to ensure a valid estimate of the risk associated with Cryptosporidium infection in dairy herds. Our aims were to obtain species-specific estimates of the prevalence of Cryptosporidium in dairy cattle and to investigate seasonal variations in prevalence. We validated our empirical estimates using a Bayesian approach. Samples were collected on 32 study farms, once in each of 3 different seasons using an age-stratified sampling design. The overall prevalence of Cryptosporidium parvum-like species and Cryptosporidium andersoni among the 1911 animals tested by the flotation method was 5% and 1%, respectively. Among preweaned calves (<65 days of age), the prevalence of C. parvum-like species was twice as high in the summer (26%) compared with the winter (11%). Herd prevalence showed the same seasonal trend. Preweaned calves were also shedding C. andersoni at an average intensity of 20 oocysts per gram of feces. We did not detect C. parvum-like oocysts in cattle older than 5 months. Sequencing of a portion of the 18s rRNA gene revealed that in the summer, 42% of the C. parvum-like oocysts shed by preweaned calves were zoonotic, compared with >74% during the rest of the year. Both empirical and stochastic methods revealed a summer peak in the prevalence of C. parvum-like oocysts in preweaned calves. Determining whether seasonal variation in the prevalence and proportion of Cryptosporidium species shed by preweaned calves is due to management practices or ecological factors will have important implications for effective control of this parasite.

  15. Trends and seasonality of reproductive performance in Florida and Georgia dairy herds from 1976 to 2002.

    PubMed

    de Vries, A; Risco, C A

    2005-09-01

    Trends in reproductive performance from 1976 to 2002 were studied for dairy farms located in Florida and Georgia using 2,897,517 Dairy Herd Improvement Association lactation records of Holstein cows. One-half of the 1552 herds in the final edited records had measures for at least 8 yr. Measures of reproductive performance changed significantly over time. Days to first service increased from a low of 84 d in 1983 to 104 d in 2001. Cows that calved during spring had 9.2 (1983) to 33.2 (1999) more days to first service than cows that calved during fall. Annual pregnancy rates (PR) for 71 to 364 d since last calving (DSC; PR(71-364)) decreased from 21.6% in 1977 to 1979, to 12% in 2000 to 2002. The greatest PR(71-364) was observed during winter and the lowest during summer (15.8 vs. 5.6% in 2002, respectively). The absolute difference between PR(71-364) during winter and summer remained similar over time at 11 percentage units. Pregnancy rates in the early stages since calving (71 to 133 d) showed greater decreases over time than PR in the later stages since calving. From 1998 to 2002, PR in the later stages since calving (134 to 364 d) was on average 11.5%. Pregnancy rate from 71 to 133 DSC remained greater (13.4%). In the winter, the decrease in PR(71-364) was primarily due to a large decrease in PR(71-91). Average days to conception increased from a low of 121 in 1982 to a high of 167 in 1998. The average difference between cows that calved during spring and fall increased from 22 d in 1976 to 47.5 d in 1986, but remained constant at 39.1 d from 1985. Average calving interval increased from 399 d in 1976 to 429 d in 2000. Average days dry between 1976 and 2001 remained similar at 69 d. Days to culling of nonpregnant cows after 182 DSC increased from 341 in 1983 to 415 in 1998. Season of calving had no clear association with average days to culling. The last milk yield recorded less than 1 mo before culling of nonpregnant cows after 182 DSC decreased by DSC to

  16. Management and characteristics of recycled manure solids used for bedding in Midwest freestall dairy herds.

    PubMed

    Husfeldt, A W; Endres, M I; Salfer, J A; Janni, K A

    2012-04-01

    were similar for all 3 bedding sources. Addition of a mechanical blower post-separation and use of a shelter for storage were associated with reduced fresh-bedding moisture but not associated with bacterial counts. This was the first survey of herds using RMS for bedding in the Midwest. We learned that RMS was being used successfully as a source of bedding for dairy cows. For most farms in the study, somatic cell count was comparable to the average in the region and not excessively high.

  17. The association between milk urea nitrogen and DHI production variables in western commercial dairy herds.

    PubMed

    Johnson, R G; Young, A J

    2003-09-01

    A retrospective observational study was conducted using data from Dairy Herd Improvement monthly tests to investigate the association between milk urea nitrogen (MUN) concentration and milk yield, milk protein, milk fat percentage, SCC, and parity for commercial Holstein and Jersey herds in Utah, Idaho, and Montana. Mean MUN for Holstein cows was 15.5 mg/ dl (5.5 mmol/L) MUN and 14.1 mg/dl (5.0 mmol/L) for Jersey cows. Mean MUN, categorized by 30-d increments of days in milk (DIM), paralleled changes in milk values and followed a curvilinear shape. For Holstein cows, concentrations of MUN were different among lactation groups 1, 2, and 3+ for the first 90 DIM for Holsteins. Overall, concentrations of MUN were lower during for the first 30 DIM compared with all other DIM categories for both Holstein and Jersey cows. Multivariate regression models of MUN by milk protein showed that as the milk protein percentage increased, MUN concentration decreased; however, models for Jersey cows showed that MUN did not decrease significantly until above 3.4% milk protein. Milk fat percentage also decreased as MUN increased, but by only 1 mg/dl MUN over the range of 2.2 to 5.8% milk fat. Somatic cell count showed a negative relationship with MUN. Holstein cows with milk protein percentage >3.2% had lower MUN compared with cows having milk protein <3.2% for milk yields from 27.3 to 54.5 kg/d and lower than cows having a milk protein <3.0% for milk yield of 54.5 to 63.6 kg/d. In Jersey cows, MUN concentrations were not different among milk protein percentage categorized by milk yield. This study found that MUN was inversely associated with milk protein percentage and paralleled change in milk yield over time.

  18. Public and farmer perceptions of dairy cattle welfare in the United States.

    PubMed

    Wolf, C A; Tonsor, G T; McKendree, M G S; Thomson, D U; Swanson, J C

    2016-07-01

    This research used surveys of the public and dairy farmers in the United States to assess perceptions and attitudes related to dairy cattle welfare. Sixty-three percent of public respondents indicated that they were concerned about dairy cattle welfare. Most public respondents agreed that animal welfare was more important than low milk prices but that the average American did not necessarily agree. Most public respondents had not viewed media stories related to dairy cattle welfare. Respondents who had viewed these stories did so on television or Internet. The United States Department of Agriculture (USDA) was viewed as the most accurate source of information related to dairy cattle welfare, followed by the Humane Society of the United States (HSUS) and the American Veterinary Medicine Association (AVMA). Both public and dairy farmer respondents viewed farmers as having the most influence on dairy cattle welfare. However, there was a general pattern of public respondents indicating that groups including USDA, HSUS, and AVMA had a relatively larger influence on dairy cattle welfare than did farmer respondents. In contrast, dairy farmers indicated that individual actors-farmers, veterinarians, consumers-had more influence than the public indicated. When asked about production practices, most public respondents indicated that they would vote for a ban on antibiotic use outside of disease treatment or for the mandated use of pain control in castration. However, a minority indicated they would vote to ban the use of recombinant bovine somatotropin (rbST) or to pay a premium for milk produced without rbST. With respect to explaining public support for the production practice bans and limits, respondents were more likely to vote for the restrictions if they were older, female, had higher income, or had viewed animal welfare stories in the media.

  19. Associations between age at first calving, rearing average daily weight gain, herd milk yield and dairy herd production, reproduction, and profitability.

    PubMed

    Krpálková, L; Cabrera, V E; Kvapilík, J; Burdych, J; Crump, P

    2014-10-01

    The objective of this study was to evaluate the associations of variable intensity in rearing dairy heifers on 33 commercial dairy herds, including 23,008 cows and 18,139 heifers, with age at first calving (AFC), average daily weight gain (ADG), and milk yield (MY) level on reproduction traits and profitability. Milk yield during the production period was analyzed relative to reproduction and economic parameters. Data were collected during a 1-yr period (2011). The farms were located in 12 regions in the Czech Republic. The results show that those herds with more intensive rearing periods had lower conception rates among heifers at first and overall services. The differences in those conception rates between the group with the greatest ADG (≥0.800 kg/d) and the group with the least ADG (≤0.699 kg/d) were approximately 10 percentage points in favor of the least ADG. All the evaluated reproduction traits differed between AFC groups. Conception at first and overall services (cows) was greatest in herds with AFC ≥800 d. The shortest days open (105 d) and calving interval (396 d) were found in the middle AFC group (799 to 750 d). The highest number of completed lactations (2.67) was observed in the group with latest AFC (≥800 d). The earliest AFC group (≤749 d) was characterized by the highest depreciation costs per cow at 8,275 Czech crowns (US$414), and the highest culling rate for cows of 41%. The most profitable rearing approach was reflected in the middle AFC (799 to 750 d) and middle ADG (0.799 to 0.700 kg) groups. The highest MY (≥8,500 kg) occurred with the earliest AFC of 780 d. Higher MY led to lower conception rates in cows, but the highest MY group also had the shortest days open (106 d) and a calving interval of 386 d. The same MY group had the highest cow depreciation costs, net profit, and profitability without subsidies of 2.67%. We conclude that achieving low AFC will not always be the most profitable approach, which will depend upon farm

  20. Associations between age at first calving, rearing average daily weight gain, herd milk yield and dairy herd production, reproduction, and profitability.

    PubMed

    Krpálková, L; Cabrera, V E; Kvapilík, J; Burdych, J; Crump, P

    2014-10-01

    The objective of this study was to evaluate the associations of variable intensity in rearing dairy heifers on 33 commercial dairy herds, including 23,008 cows and 18,139 heifers, with age at first calving (AFC), average daily weight gain (ADG), and milk yield (MY) level on reproduction traits and profitability. Milk yield during the production period was analyzed relative to reproduction and economic parameters. Data were collected during a 1-yr period (2011). The farms were located in 12 regions in the Czech Republic. The results show that those herds with more intensive rearing periods had lower conception rates among heifers at first and overall services. The differences in those conception rates between the group with the greatest ADG (≥0.800 kg/d) and the group with the least ADG (≤0.699 kg/d) were approximately 10 percentage points in favor of the least ADG. All the evaluated reproduction traits differed between AFC groups. Conception at first and overall services (cows) was greatest in herds with AFC ≥800 d. The shortest days open (105 d) and calving interval (396 d) were found in the middle AFC group (799 to 750 d). The highest number of completed lactations (2.67) was observed in the group with latest AFC (≥800 d). The earliest AFC group (≤749 d) was characterized by the highest depreciation costs per cow at 8,275 Czech crowns (US$414), and the highest culling rate for cows of 41%. The most profitable rearing approach was reflected in the middle AFC (799 to 750 d) and middle ADG (0.799 to 0.700 kg) groups. The highest MY (≥8,500 kg) occurred with the earliest AFC of 780 d. Higher MY led to lower conception rates in cows, but the highest MY group also had the shortest days open (106 d) and a calving interval of 386 d. The same MY group had the highest cow depreciation costs, net profit, and profitability without subsidies of 2.67%. We conclude that achieving low AFC will not always be the most profitable approach, which will depend upon farm

  1. Bacterial subclinical mastitis and its effect on milk yield in low-input dairy goat herds.

    PubMed

    Gelasakis, A I; Angelidis, A S; Giannakou, R; Filioussis, G; Kalamaki, M S; Arsenos, G

    2016-05-01

    The objectives of this study were (1) to record the major pathogens associated with subclinical mastitis (SCM), (2) to calculate their incidence during the milking period, and (3) to estimate the effect of SCM on daily milk yield (DMY) for goats reared under low-input management schemes. Dairy goats (n=590) of Skopelos and indigenous Greek breeds from 4 herds were randomly selected for the study. The study included monthly monitoring, milk yield recording, and bacteriological analyses of milk of individual goats during the course of 2 successive milking periods. Incidence and cumulative incidence were calculated for SCM cases. Moreover, 2 mixed linear regression models were built to assess the effects of (1) SCM and (2) different pathogens isolated from SCM cases, on DMY. The estimated incidence and cumulative incidence of SCM for the first and the second year of the study were 69.5 and 96.4 new cases of SCM/1,000 goat-months, and 24.1 and 31.7%, respectively. A total of 755 milk samples were subjected to microbiological examination, resulting in 661 positive cultures. Coagulase-negative and coagulase-positive staphylococci were isolated from 50.2 and 34.5% of the positive cultures, respectively. The incidence of infections (new infections per 1,000 goat-months) for the first and the second year of the study were 34 and 53 for coagulase-negative staphylococci, 23 and 28 for coagulase-positive staphylococci, 3 and 5 for Streptococcus/Enterococcus spp., and 5.5 and 9.1 for gram-negative bacteria. Goats with SCM had lower DMY when compared with goats without SCM (ca. 47g/d, corresponding to a 5.7% decrease in DMY). In particular, goats with SCM due to coagulase-positive staphylococci infection produced approximately 80g/d less milk (a reduction of ca. 9.7%) compared with uninfected ones, whereas SCM due to gram-negative bacteria resulted in approximately 15% reduction in DMY. Investigating the epidemiology of SCM and its effects on production traits is critical for

  2. Bacterial subclinical mastitis and its effect on milk yield in low-input dairy goat herds.

    PubMed

    Gelasakis, A I; Angelidis, A S; Giannakou, R; Filioussis, G; Kalamaki, M S; Arsenos, G

    2016-05-01

    The objectives of this study were (1) to record the major pathogens associated with subclinical mastitis (SCM), (2) to calculate their incidence during the milking period, and (3) to estimate the effect of SCM on daily milk yield (DMY) for goats reared under low-input management schemes. Dairy goats (n=590) of Skopelos and indigenous Greek breeds from 4 herds were randomly selected for the study. The study included monthly monitoring, milk yield recording, and bacteriological analyses of milk of individual goats during the course of 2 successive milking periods. Incidence and cumulative incidence were calculated for SCM cases. Moreover, 2 mixed linear regression models were built to assess the effects of (1) SCM and (2) different pathogens isolated from SCM cases, on DMY. The estimated incidence and cumulative incidence of SCM for the first and the second year of the study were 69.5 and 96.4 new cases of SCM/1,000 goat-months, and 24.1 and 31.7%, respectively. A total of 755 milk samples were subjected to microbiological examination, resulting in 661 positive cultures. Coagulase-negative and coagulase-positive staphylococci were isolated from 50.2 and 34.5% of the positive cultures, respectively. The incidence of infections (new infections per 1,000 goat-months) for the first and the second year of the study were 34 and 53 for coagulase-negative staphylococci, 23 and 28 for coagulase-positive staphylococci, 3 and 5 for Streptococcus/Enterococcus spp., and 5.5 and 9.1 for gram-negative bacteria. Goats with SCM had lower DMY when compared with goats without SCM (ca. 47g/d, corresponding to a 5.7% decrease in DMY). In particular, goats with SCM due to coagulase-positive staphylococci infection produced approximately 80g/d less milk (a reduction of ca. 9.7%) compared with uninfected ones, whereas SCM due to gram-negative bacteria resulted in approximately 15% reduction in DMY. Investigating the epidemiology of SCM and its effects on production traits is critical for

  3. Trends in udder health and emerging mastitogenic pathogens in South African dairy herds.

    PubMed

    Petzer, I-M; Karzis, J; Watermeyer, J C; van der Schans, T J; van Reenen, R

    2009-03-01

    The aim of this study was to retrospectively analyse the results of milk samples obtained from South African dairy herds during the period 1996 to April 2007 in order to identify possible trends in isolates of microorganisms and their pathogenicity under field conditions. Milk samples were obtained from 7 of the 9 provinces in South Africa where there are low numbers of dairy cows. Although there is scientific limitation to a country wide survey, such as the variation in herd size, management skills, parity, milk yield, milking frequency and other parameters, the size of this database helps to give a fair indication of general udder health in South Africa. Cytology and routine bacteriology were performed on 379,000 milk samples of lactating cows and bacteriology on 11,946 samples from non-lactating cows. According to the results obtained, mastitis did not decrease in South Africa over the test period. The prevalence of mastitis and teat canal infection was lowest in 2002. Mastitis and teat canal infection increased from 2002 to 2006 from 8.1% and 24.1% to 15.4 and 30.0% respectively. The percentage of mastitogenic pathogens isolated from cows over these years also varied. Previously unknown or almost eradicated mastitogenic pathogens such as alphabeta haemolytic Staphylococcus aureus which is thought to be of human origin, Streptococcus agalactiae and Enterococcus canis were responsible for numerous mastitis outbreaks seen in the test samples. Coagulase-negative staphylococci were the most frequently isolated bacteria in milk samples from both lactating and dry cows, followed by Staphylococcus aureus and Streptococcus agalactiae. Although Staphylococcus aureus remained the principal mastitogenic pathogen in South Africa, owing to its chronic nature and resultant economic losses, most cases of mastitis were caused by coagulase-negative staphylococci. This finding increases the importance of coagulase-negative staphylococci (formerly described as a minor pathogen

  4. Screening for subclinical ketosis in dairy cattle by Fourier transform infrared spectrometry.

    PubMed

    de Roos, A P W; van den Bijgaart, H J C M; Hørlyk, J; de Jong, G

    2007-04-01

    Subclinical ketosis is a metabolic disorder in high-producing dairy cattle that can be detected by ketone bodies in milk: acetone (Ac), acetoacetate (AcAc), and beta-hydroxybutyrate (BHBA). Fourier transform infrared (FTIR) spectrometry is to a growing extent used for determination of milk constituents in milk recording, but as yet there is no calibration for ketone bodies available. The objective of this study was therefore to build a calibration for the MilkoScan FT6000 (FOSS Analytical A/S, Hillerød, Denmark) for Ac, AcAc, and BHBA and to evaluate the FTIR predictions for detection of subclinical ketosis. From 217 herds, 1,080 milk samples were taken from fresh multiparous dairy cows. The Ac, AcAc, and BHBA concentrations were determined by chemical methods using segmented flow analysis. Because of its low concentration, AcAc seemed to be hardly detectable and was therefore not considered further. The correlation between the chemical method results of Ac and BHBA was 0.82, indicating that both ketone bodies were elevated in milk during subclinical ketosis. In wk 1 postpartum, however, most samples with a high Ac concentration did not have a high BHBA concentration, whereas after wk 5 postpartum most samples with a high BHBA concentration did not have a high Ac concentration. For Ac and BHBA, the correlation coefficients between the FTIR predictions and the chemical results were around 0.80 with standard error of cross validation values of 0.184 and 0.064 mM for Ac and BHBA, respectively. Using thresholds of 0.15 mM for Ac and 0.10 mM for BHBA, high values for Ac or BHBA were detected with a sensitivity of 69 to 70%, a specificity of 95%, with 25 to 27% false positives and 6 to 7% false negatives. It is argued that FTIR predictions for Ac and BHBA are valuable for screening cows on subclinical ketosis, especially when used in combination with other indicators, and can serve in the evaluation of the herd health status with respect to subclinical ketosis.

  5. Use of metabolic profiles in dairy cattle in tropical and subtropical countries on smallholder dairy farms.

    PubMed

    Whitaker, D A; Goodger, W J; Garcia, M; Perera, B M; Wittwer, F

    1999-01-27

    Metabolic profile testing has generally been used as part of a multidisciplinary approach for dairy herds in temperate climates. Our goal was to evaluate the effectiveness of the technique for identifying constraints on productivity in small herds in environments less favorable for milk production. Metabolites tested were chosen for stability in the sample after collection of blood, ease of analysis and practical knowledge of the meaning of the results. Blood levels of five different metabolites in low-producing dairy cows belonging to smallholders in tropical and subtropical environments were measured. The study involved 13 projects with 80 cows in each, carried out in six Latin American, six Asian, and one southern European countries. Data were also collected on feeding, body condition score (BCS) and weight change, parasitism, and reproduction. In Chile, Mexico, Paraguay, Philippines, Uruguay, and Venezuela, globulin levels were high in > 17% of cows sampled on each occasion. Globulin levels were also high in Turkey and Vietnam on one or more occasions. In Paraguay, 49% of cows had high globulin levels at two to three months after calving. These results suggest that inflammatory disease was present to a potentially important degree, although this was not always investigated and not always taken into account. In all countries except Mexico and Venezuela, high beta-hydroxybutyrate (BHB) levels before calving in many cows highlighted the presence of condition loss in late pregnancy, an important potential constraint on productivity and fertility. Fewer cows showed high BHB levels in lactation, whereas change in BCS and weight was more sensitive for measuring negative energy balance. Urea concentrations were low in only small numbers of cows suggesting that dietary protein shortages were not common. Albumin values were low mainly in cows where globulin values were high and, hence, did not generally provide additional information. The exception was in China where

  6. Use of metabolic profiles in dairy cattle in tropical and subtropical countries on smallholder dairy farms.

    PubMed

    Whitaker, D A; Goodger, W J; Garcia, M; Perera, B M; Wittwer, F

    1999-01-27

    Metabolic profile testing has generally been used as part of a multidisciplinary approach for dairy herds in temperate climates. Our goal was to evaluate the effectiveness of the technique for identifying constraints on productivity in small herds in environments less favorable for milk production. Metabolites tested were chosen for stability in the sample after collection of blood, ease of analysis and practical knowledge of the meaning of the results. Blood levels of five different metabolites in low-producing dairy cows belonging to smallholders in tropical and subtropical environments were measured. The study involved 13 projects with 80 cows in each, carried out in six Latin American, six Asian, and one southern European countries. Data were also collected on feeding, body condition score (BCS) and weight change, parasitism, and reproduction. In Chile, Mexico, Paraguay, Philippines, Uruguay, and Venezuela, globulin levels were high in > 17% of cows sampled on each occasion. Globulin levels were also high in Turkey and Vietnam on one or more occasions. In Paraguay, 49% of cows had high globulin levels at two to three months after calving. These results suggest that inflammatory disease was present to a potentially important degree, although this was not always investigated and not always taken into account. In all countries except Mexico and Venezuela, high beta-hydroxybutyrate (BHB) levels before calving in many cows highlighted the presence of condition loss in late pregnancy, an important potential constraint on productivity and fertility. Fewer cows showed high BHB levels in lactation, whereas change in BCS and weight was more sensitive for measuring negative energy balance. Urea concentrations were low in only small numbers of cows suggesting that dietary protein shortages were not common. Albumin values were low mainly in cows where globulin values were high and, hence, did not generally provide additional information. The exception was in China where

  7. Evidence supporting vertical transmission of Salmonella in dairy cattle.

    PubMed

    Hanson, D L; Loneragan, G H; Brown, T R; Nisbet, D J; Hume, M E; Edrington, T S

    2016-04-01

    We set out to investigate whether Salmonella enterica could be recovered from various tissues of viable neonatal calves immediately following parturition. Eleven samples were aseptically collected from each of 20 calves and consisted of both left and right subiliac and prescapular lymph nodes (LN), mesenteric LN, spleen and liver, as well as intestinal tissue (including luminal contents) from the small intestine, caecum, spiral colon and rectum. In addition, a faecal sample was collected from 19 of the dams. Salmonella was recovered from at least one sample from 10 of the 20 neonates. Across all calves, Salmonella was recovered from 12·7% of all samples and from LN in particular, Salmonella was recovered from 10·0%, 5·0%, and 5·0% of subiliac, prescapular, and mesenteric LN, respectively. Within calves, Salmonella was recovered from 0% to 73% of samples and across tissues, estimates of Salmonella prevalence were greatest in the caecum (30%) but was never recovered from the right pre-scapular LN. These data provide evidence of vertical transmission from a dam to her fetus such that viable calves are born already infected and thereby not requiring faecal-oral exposure for transmission. This new knowledge ought to challenge - or at least add to - existing paradigms of Salmonella transmission dynamics within cattle herds. PMID:26419321

  8. The DD Check App for prevention and control of digital dermatitis in dairy herds.

    PubMed

    Tremblay, Marlène; Bennett, Tom; Döpfer, Dörte

    2016-09-15

    Digital dermatitis (DD) is the most important infectious claw disease in the cattle industry causing outbreaks of lameness. The clinical course of disease can be classified using 5 clinical stages. M-stages represent not only different disease severities but also unique clinical characteristics and outcomes. Monitoring the proportions of cows per M-stage is needed to better understand and address DD and factors influencing risks of DD in a herd. Changes in the proportion of cows per M-stage over time or between groups may be attributed to differences in management, environment, or treatment and can have impact on the future claw health of the herd. Yet trends in claw health regarding DD are not intuitively noticed without statistical analysis of detailed records. Our specific aim was to develop a mobile application (app) for persons with less statistical training, experience or supporting programs that would standardize M-stage records, automate data analysis including trends of M-stages over time, the calculation of predictions and assignments of Cow Types (i.e., Cow Types I-III are assigned to cows without active lesions, single and repeated cases of active DD lesions, respectively). The predictions were the stationary distributions of transitions between DD states (i.e., M-stages or signs of chronicity) in a class-structured multi-state Markov chain population model commonly used to model endemic diseases. We hypothesized that the app can be used at different levels of record detail to discover significant trends in the prevalence of M-stages that help to make informed decisions to prevent and control DD on-farm. Four data sets were used to test the flexibility and value of the DD Check App. The app allows easy recording of M-stages in different environments and is flexible in terms of the users' goals and the level of detail used. Results show that this tool discovers trends in M-stage proportions, predicts potential outbreaks of DD, and makes comparisons among

  9. The DD Check App for prevention and control of digital dermatitis in dairy herds.

    PubMed

    Tremblay, Marlène; Bennett, Tom; Döpfer, Dörte

    2016-09-15

    Digital dermatitis (DD) is the most important infectious claw disease in the cattle industry causing outbreaks of lameness. The clinical course of disease can be classified using 5 clinical stages. M-stages represent not only different disease severities but also unique clinical characteristics and outcomes. Monitoring the proportions of cows per M-stage is needed to better understand and address DD and factors influencing risks of DD in a herd. Changes in the proportion of cows per M-stage over time or between groups may be attributed to differences in management, environment, or treatment and can have impact on the future claw health of the herd. Yet trends in claw health regarding DD are not intuitively noticed without statistical analysis of detailed records. Our specific aim was to develop a mobile application (app) for persons with less statistical training, experience or supporting programs that would standardize M-stage records, automate data analysis including trends of M-stages over time, the calculation of predictions and assignments of Cow Types (i.e., Cow Types I-III are assigned to cows without active lesions, single and repeated cases of active DD lesions, respectively). The predictions were the stationary distributions of transitions between DD states (i.e., M-stages or signs of chronicity) in a class-structured multi-state Markov chain population model commonly used to model endemic diseases. We hypothesized that the app can be used at different levels of record detail to discover significant trends in the prevalence of M-stages that help to make informed decisions to prevent and control DD on-farm. Four data sets were used to test the flexibility and value of the DD Check App. The app allows easy recording of M-stages in different environments and is flexible in terms of the users' goals and the level of detail used. Results show that this tool discovers trends in M-stage proportions, predicts potential outbreaks of DD, and makes comparisons among

  10. New phenotypes for new breeding goals in dairy cattle.

    PubMed

    Boichard, D; Brochard, M

    2012-04-01

    Cattle production faces new challenges regarding sustainability with its three pillars - economic, societal and environmental. The following three main factors will drive dairy cattle selection in the future: (1) During a long period, intensive selection for enhanced productivity has deteriorated most functional traits, some reaching a critical point and needing to be restored. This is especially the case for the Holstein breed and for female fertility, mastitis resistance, longevity and metabolic diseases. (2) Genomic selection offers two new opportunities: as the potential genetic gain can be almost doubled, more traits can be efficiently selected; phenotype recording can be decoupled from selection and limited to several thousand animals. (3) Additional information from other traits can be used, either from existing traditional recording systems at the farm level or from the recent and rapid development of new technologies and precision farming. Milk composition (i.e. mainly fatty acids) should be adapted to better meet human nutritional requirements. Fatty acids can be measured through a new interpretation of the usual medium infrared spectra. Milk composition can also provide additional information about reproduction and health. Modern milk recorders also provide new information, that is, on milking speed or on the shape of milking curves. Electronic devices measuring physiological or activity parameters can predict physiological status like estrus or diseases, and can record behavioral traits. Slaughterhouse data may permit effective selection on carcass traits. Efficient observatories should be set up for early detection of new emerging genetic defects. In the near future, social acceptance of cattle production could depend on its capacity to decrease its ecological footprint. The first solution consists in increasing survival and longevity to reduce replacement needs and the number of nonproductive animals. At the individual level, selection on rumen

  11. New phenotypes for new breeding goals in dairy cattle.

    PubMed

    Boichard, D; Brochard, M

    2012-04-01

    Cattle production faces new challenges regarding sustainability with its three pillars - economic, societal and environmental. The following three main factors will drive dairy cattle selection in the future: (1) During a long period, intensive selection for enhanced productivity has deteriorated most functional traits, some reaching a critical point and needing to be restored. This is especially the case for the Holstein breed and for female fertility, mastitis resistance, longevity and metabolic diseases. (2) Genomic selection offers two new opportunities: as the potential genetic gain can be almost doubled, more traits can be efficiently selected; phenotype recording can be decoupled from selection and limited to several thousand animals. (3) Additional information from other traits can be used, either from existing traditional recording systems at the farm level or from the recent and rapid development of new technologies and precision farming. Milk composition (i.e. mainly fatty acids) should be adapted to better meet human nutritional requirements. Fatty acids can be measured through a new interpretation of the usual medium infrared spectra. Milk composition can also provide additional information about reproduction and health. Modern milk recorders also provide new information, that is, on milking speed or on the shape of milking curves. Electronic devices measuring physiological or activity parameters can predict physiological status like estrus or diseases, and can record behavioral traits. Slaughterhouse data may permit effective selection on carcass traits. Efficient observatories should be set up for early detection of new emerging genetic defects. In the near future, social acceptance of cattle production could depend on its capacity to decrease its ecological footprint. The first solution consists in increasing survival and longevity to reduce replacement needs and the number of nonproductive animals. At the individual level, selection on rumen

  12. The diversity of bovine MHC class II DRB3 and DQA1 alleles in different herds of Japanese Black and Holstein cattle in Japan.

    PubMed

    Miyasaka, Taku; Takeshima, Shin-nosuke; Matsumoto, Yuki; Kobayashi, Naohiko; Matsuhashi, Tamako; Miyazaki, Yoshiyuki; Tanabe, Yoshihiro; Ishibashi, Kazuki; Sentsui, Hiroshi; Aida, Yoko

    2011-02-01

    In cattle, bovine leukocyte antigens (BoLAs) have been extensively used as markers for bovine diseases and immunological traits. In this study, we sequenced alleles of the BoLA class II loci, BoLA-DRB3 and BoLA-DQA1, from 650 Japanese cattle from six herds [three herds (507 animals) of Japanese Black cattle and three herds (143 animals) of Holstein cattle] using polymerase chain reaction-sequence-based typing (PCR-SBT) methods. We identified 26 previously reported distinct DRB3 alleles in the two populations: 22 in Japanese Black and 17 in Holstein. The number of DRB3 alleles detected in each herd ranged from 9 to 20. Next, we identified 15 previously reported distinct DQA1 alleles: 13 in Japanese Black and 10 in Holstein. The number of alleles in each herd ranged from 6 to 10. Thus, allelic divergence is significantly greater for DRB3 than for DQA1. A population tree on the basis of the frequencies of the DRB3 and DQA1 alleles showed that, although the genetic distance differed significantly between the two cattle breeds, it was closely related within the three herds of each breed. In addition, Wu-Kabat variability analysis indicated that the DRB3 gene was more polymorphic than the DQA1 gene in both breeds and in all herds, and that the majority of the hypervariable positions within both loci corresponded to pocket-forming residues. The DRB3 and DQA1 heterozygosity for both breeds within each herd were calculated based on the Hardy-Weinberg equilibrium. Only one Japanese Black herd showed a significant difference between the expected and observed heterozygosity at both loci. This is the first report presenting a detailed study of the allelic distribution of BoLA-DRB3 and -DQA1 genes in Japanese Black and Holstein cattle from different farms in Japan. These results may help to develop improved livestock breeding strategies in the future. PMID:20965236

  13. Management factors related to seroprevalences to bovine viral-diarrhoea virus, bovine-leukosis virus, Mycobacterium avium subspecies paratuberculosis, and Neospora caninum in dairy herds in the Canadian Maritimes.

    PubMed

    Chi, Junwook; VanLeeuwen, John A; Weersink, Alfons; Keefe, Gregory P

    2002-09-10

    Bovine viral-diarrhoea (BVD), enzootic bovine leukosis (EBL), Johne's disease (JD), and neosporosis lower on-farm productivity, reduce export competitiveness, and increase consumer concerns regarding safety. Our purpose was to examine the relationship between 27 control practices and the estimated true seroprevalences for these four diseases for 2604 cattle in 90 dairy herds in the Maritimes provinces of Canada. Overall, 37.8, 20.4, 3.4, and 19.2% of all sampled cattle were truly exposed to the agents of BVD, EBL, JD, and neosporosis, respectively. The median within-herd true prevalences were 0, 9.3, 0, and 12.3%, respectively. Factor analysis reduced the 27 control practices to two highly correlated factors. Tobit-regression analyses determined that vaccination practices were associated with reduced prevalence of exposure for Bovine viral-diarrhoea and EBL. Also, farms that tended to purchase their dairy animals were associated with higher seroprevalence for Johnes' disease. Neither of these two factors was associated with the seroprevalence of Neospora caninum infection. The few routine biosecurity measures that were investigated in this study were generally not related to the seroprevalences of these farms. PMID:12324207

  14. Herd characteristics and cow-level factors associated with Prototheca mastitis on dairy farms in Ontario, Canada.

    PubMed

    Pieper, L; Godkin, A; Roesler, U; Polleichtner, A; Slavic, D; Leslie, K E; Kelton, D F

    2012-10-01

    Prototheca spp. are algae that cause incurable acute or chronic mastitis in dairy cows. The aim of this case-control study was the identification of cow- and herd-level risk factors for this unusual mastitis pathogen. Aseptically collected composite milk samples from 2,428 milking cows in 23 case and 23 control herds were collected between January and May 2011. A questionnaire was administered to the producers, and cow-level production and demographic data were gathered. In 58 of 64 isolates, Prototheca spp. and Prototheca zopfii genotypes were differentiated using PCR and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. All isolates were identified as Prototheca zopfii genotype 2. The mean within-herd prevalence for Prototheca spp. was 5.1% (range 0.0-12.5%). Case herds had a significantly lower herd-level prevalence of Staphylococcus aureus and a higher prevalence of yeasts than did control herds. The final logistic regression model for herd-level risk factors included use of intramammary injections of a non-intramammary drug [odds ratio (OR) = 136.8], the number of different injectable antibiotic products being used (OR = 2.82), the use of any dry cow teat sealant (external OR = 80.0; internal OR = 34.2), and having treated 3 or more displaced abomasums in the last 12 mo OR = 44.7). The final logistic regression model for cow-level risk factors included second or greater lactation (OR = 4.40) and the logarithm of the lactation-average somatic cell count (OR = 2.99). Unsanitary or repeated intramammary infusions, antibiotic treatment, and off-label use of injectable drugs in the udder might promote Prototheca udder infection. PMID:22884347

  15. Kosovo’s Public Health Damage from Abusive Use of Antibiotics in Dairy Cattle

    PubMed Central

    Ibraimi, Zana; Shehi, Agim; Murtezani, Ardiana; Krasniqi, Shaip; Agani, Zana

    2015-01-01

    Introduction: The aim of the study is to assess the state of the use of antibiotics in dairy cattle in Kosovo according to different diagnosis as directed by treatment protocol and to evaluate the methods of their application in dairy cattle. Methods: We’ve visited over 80% of dairy farms throughout the territory of Kosovo in 2013. Assessment was carried out through a specific questionnaire, which identifies problems with medical treatment of cattle, the number of cattle treated and untreated, description of dose and type of drugs used, as well as the duration of drugs issuance. Results: In Kosovo for the treatment of sick cows are mainly used beta lactams and sulfonamides. The drugs were not given only to sick cattle by their diagnosis, but they were given to healthy cattle too, as a preventative therapy, mainly through intramuscular route. Conclusion: We conclude that the dairy cattle were not treated correctly as directed by the treatment protocol. In Kosovo’s general health system there are no rules and procedures on monitoring and recording the expenditures on antibiotics. PMID:26244043

  16. Assessment of Fatty Liver Syndrome and Its Predisposing Factors in a Dairy Herd from Venezuela

    PubMed Central

    Gonzalez, Clara I.

    2013-01-01

    The present on-farm research evaluated the occurrence of fatty liver syndrome and its predisposing risk factors for multiparous dairy cows from a commercial herd in Venezuela. Liver biopsy samples were collected at 35 days (d) prepartum (Holstein, n = 14; Holstein × Carora crossbred, n = 17) as well as 1 to 7 d (Holstein, n = 8; Holstein × Carora crossbred, n = 11) and 28 to 35 d (Holstein, n = 6; Holstein × Carora crossbred, n = 14) postpartum in order to analyse hepatic triacylglycerols (TAG, % wet basis) and glycogen concentrations. At postpartum, an occurrence of 72.0% for severe fatty liver along with 73.5% of subclinical ketosis (SCK) was found. The multiple regression model that best explained the association between milk production in the previous lactation (MYP) and TAG at first week postpartum was as follows: TAG, % = −11.2 + 3.16 (prepartum body condition) + 0.0009176 (MYP) (R² = 0.36, P < 0.05). Logistic regression indicated that Holstein × Carora crossbred cows tended to have 27% higher relative risk than Holstein to experience SCK, whereas prepartum liver TAG greater than 3% tended to be associated with a higher relative risk for SCK compared to cows with TAG ≤3%. PMID:23738138

  17. Smallholder experiences with dairy cattle crossbreeding in the tropics: from introduction to impact.

    PubMed

    Roschinsky, R; Kluszczynska, M; Sölkner, J; Puskur, R; Wurzinger, M

    2015-01-01

    Crossbreeding of indigenous tropical and improved western dairy cattle breeds as tool to improve dairy cattle performance on smallholder farms has been widely advocated, criticised and yet applied. The government of Ethiopia supported this technology for decades but adoption rate is low. Constraints are documented but there is little information about farm level introduction and development of crossbreeding. A total 122 smallholders with mixed crop livestock farms and at least 8 years of successful crossbreeding were interviewed using a pre-tested questionnaire in two contexts in Amhara Regional state in north-western Ethiopia. Crossbreeding initiator was either uncoordinated government extension or a coordinated development project, also implemented with governmental support. Qualitative and quantitative data on farmers' motivations, crossbreeding introduction, initiator support, breeding adaptation and impacts at farm level were analysed. Results show that even though motives vary between contexts the underlying reason to introduce crossbreeding was economic profit. To be able to introduce crossbreeding support of initiators (e.g. extension) and other farmers was essential. The crossbreeding introduction context had some influence. Governmental actors were the main source of support and supplier of exotic genetics but the farmer network acted as safety net filling gaps of government support. Breeding strategies focused on performance increase. A lack of basic understanding of crossbreeding has been identified. A surprising, probably biased, result was general satisfaction with initiator support and with breeding services. It was challenged by the high proportion of farmers unable to follow a breeding strategy due to insufficient bull and/or semen supply. Crossbreeding changed the smallholder production system to a high input - high output system. Except for crossbred adaptation problems, challenges were ranked context specific and influenced by the initiator

  18. Smallholder experiences with dairy cattle crossbreeding in the tropics: from introduction to impact.

    PubMed

    Roschinsky, R; Kluszczynska, M; Sölkner, J; Puskur, R; Wurzinger, M

    2015-01-01

    Crossbreeding of indigenous tropical and improved western dairy cattle breeds as tool to improve dairy cattle performance on smallholder farms has been widely advocated, criticised and yet applied. The government of Ethiopia supported this technology for decades but adoption rate is low. Constraints are documented but there is little information about farm level introduction and development of crossbreeding. A total 122 smallholders with mixed crop livestock farms and at least 8 years of successful crossbreeding were interviewed using a pre-tested questionnaire in two contexts in Amhara Regional state in north-western Ethiopia. Crossbreeding initiator was either uncoordinated government extension or a coordinated development project, also implemented with governmental support. Qualitative and quantitative data on farmers' motivations, crossbreeding introduction, initiator support, breeding adaptation and impacts at farm level were analysed. Results show that even though motives vary between contexts the underlying reason to introduce crossbreeding was economic profit. To be able to introduce crossbreeding support of initiators (e.g. extension) and other farmers was essential. The crossbreeding introduction context had some influence. Governmental actors were the main source of support and supplier of exotic genetics but the farmer network acted as safety net filling gaps of government support. Breeding strategies focused on performance increase. A lack of basic understanding of crossbreeding has been identified. A surprising, probably biased, result was general satisfaction with initiator support and with breeding services. It was challenged by the high proportion of farmers unable to follow a breeding strategy due to insufficient bull and/or semen supply. Crossbreeding changed the smallholder production system to a high input - high output system. Except for crossbred adaptation problems, challenges were ranked context specific and influenced by the initiator

  19. Distribution of Fasciola hepatica in Swedish dairy cattle and associations with pasture management factors.

    PubMed

    Novobilský, Adam; Sollenberg, Sofia; Höglund, Johan

    2015-01-01

    The geographic distribution of Fasciola hepatica infection in relation to management routines was studied in Swedish dairy herds by testing for F. hepatica antibodies with the enzyme-linked immunosorbent assay (ELISA). In addition, all farmers were sent a questionnaire asking for information about type of production, management routines and historical record of F. hepatica at slaughter. A total of 176 farmers (41%) responded to the questionnaire. A total of 426 bulk tank milk (BTM) samples were randomly selected from the period September to October 2012 representing approximately 10% of all herds in Sweden. The overall seroprevalence was 25% (n = 107; 95% confidence interval = 21-29%) with a concentration of herds located in south-western Sweden. Among the seropositive herds, 31 (29%) had antibody levels indicating production loss. There were no significant differences in seropositivity between organic and conventional herds or due to pasture management routines. The length of grazing period, which increased the risk for heifers, was found to be the most influential factor. A discrepancy was noted between reported F. hepatica presence at meat inspection and herds that were seropositive based on BTM-ELISA results. Although the largest proportion of seropositive BTM samples (80%) came from herds where liver fluke presence had been observed at meat inspection after slaughter, seropositive BTM samples were also diagnosed in five herds (17%) with no remarks at slaughter. In conclusion, F. hepatica is a common parasite in Swedish dairy herds and the month of heifer turn-out and the grazing period length were the most influential factors observed. PMID:25826310

  20. Genomic selection for producer-recorded health event data in US dairy cattle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Emphasizing increased profit through increased dairy cow production has revealed a negative relationship with fitness and health traits. Decreased cow health can impact herd profitability through increased rates of involuntary culling and decreased or lost milk sales. Improvement of health traits t...

  1. Dairy Cattle Management Impacts Manure Nitrogen Collection and Cycling Through Crops

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Escalating energy and fertilizer N prices, and regulatory limits on ammonia emissions from livestock facilities require methods that reduce manure management costs, enhance the fertilizer value of manure and reduce gaseous ammonia losses. We compared two dairy herd management practices on manure N c...

  2. Dairy Cattle Management Impacts Manure N Collection and Cycling Through Crops in Wisconsin, USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Escalating energy and fertilizer N prices and regulatory limits on ammonia emissions from livestock facilities require new methods that reduce manure management costs, enhance the fertilizer value of manure and reduce ammonia volatilization. We compared two dairy herd management practices on manure ...

  3. Transgenic dairy cattle: genetic engineering on a large scale.

    PubMed

    Wall, R J; Kerr, D E; Bondioli, K R

    1997-09-01

    Amid the explosion of fundamental knowledge generated from transgenic animal models, a small group of scientists has been producing transgenic livestock with goals of improving animal production efficiency and generating new products. The ability to modify mammary-specific genes provides an opportunity to pursue several distinctly different avenues of research. The objective of the emerging gene "pharming" industry is to produce pharmaceuticals for treating human diseases. It is argued that mammary glands are an ideal site for producing complex bioactive proteins that can be cost effectively harvested and purified. Consequently, during the past decade, approximately a dozen companies have been created to capture the US market for pharmaceuticals produced from transgenic bioreactors estimated at $3 billion annually. Several products produced in this way are now in human clinical trials. Another research direction, which has been widely discussed but has received less attention in the laboratory, is genetic engineering of the bovine mammary gland to alter the composition of milk destined for human consumption. Proposals include increasing or altering endogenous proteins, decreasing fat, and altering milk composition to resemble that of human milk. Initial studies using transgenic mice to investigate the feasibility of enhancing manufacturing properties of milk have been encouraging. The potential profitability of gene "pharming" seems clear, as do the benefits of transgenic cows producing milk that has been optimized for food products. To take full advantage of enhanced milk, it may be desirable to restructure the method by which dairy producers are compensated. However, the cost of producing functional transgenic cattle will remain a severe limitation to realizing the potential of transgenic cattle until inefficiencies of transgenic technology are overcome. These inefficiencies include low rates of gene integration, poor embryo survival, and unpredictable transgene

  4. Seroepidemiologic survey in Thailand of Coxiella burnetii infection in cattle and chickens and presence in ticks attached to dairy cattle.

    PubMed

    Muramatsu, Yasukazu; Usaki, Noriyo; Thongchai, Chalermchaikit; Kramomtong, Indhira; Kriengsak, Poonsuk; Tamura, Yutaka

    2014-09-01

    A seroepidemiologic survey of Coxiella burnetii in cattle and chickens in Thailand was carried out using indirect fluorescent antibody test. Nine of the 130 serum samples from cattle were positive for antibodies against C. burnetii, with antibody titers ranging from 32 to 64. Only one of 113 serum samples from chickens was seropositive, with antibody titer of 16. No C. burnetii-specific DNA was detected using restriction fragment length polymorphism-nested PCR in spleens of cattle and chickens. However, coxiella DNA was detected in two of 102 engorged Rhipicephalus microplus ticks attached to dairy cattle. These results indicated that infestation of C. burnetii among cattle and chickens is considerably low in Thailand. PMID:25417520

  5. Development of a noninvasive system for monitoring dairy cattle sleep.

    PubMed

    Klefot, J M; Murphy, J L; Donohue, K D; O'Hara, B F; Lhamon, M E; Bewley, J M

    2016-10-01

    Limited research has been conducted to assess sleep in production livestock primarily because of limitations with monitoring capabilities. Consequently, biological understanding of production circumstances and facility options that affect sleep is limited. The objective of this study was to assess if data collected from a proof-of-concept, noninvasive 3-axis accelerometer device are correlated with sleep and wake-like behaviors in dairy cattle. Four Holstein dairy cows housed at the University of Kentucky Coldstream Dairy in September 2013 were visually observed for 2 consecutive 24-h periods. The accelerometer device was attached to a harness positioned on the right side of each cow's neck. Times of classified behaviors of wake (standing, head up, alert, eyes open) or sleep-like behaviors (lying, still, head resting on ground, eyes closed) were recorded continuously by 2 observers who each watched 2 cows at a time. The radial signal was extracted from 3 different axes of the accelerometer to obtain a motion signal independent of direction of movement. Radial signal features were examined for maximizing the performance of detecting sleep-like behaviors using a Fisher's linear discriminant analysis classifier. The study included 652min of high-activity wake behaviors and 107min of sleep-like behavior among 4 cows. Results from a bootstrapping analysis showed an agreement between human observation and the linear discriminant analysis classifier, with an accuracy of 93.7±0.7% for wake behavior and 92.2±0.8% for sleep-like behavior (±95% confidence interval).This prototype shows promise in measuring sleep-like behaviors. Improvements to both hardware and software should allow more accurate determinations of subtle head movements and respiratory movements that will further improve the assessment of these sleep-like behaviors, including estimates of deep, light, and rapid eye movement sleep. These future studies will require simultaneous electroencephalography and

  6. Development of a noninvasive system for monitoring dairy cattle sleep.

    PubMed

    Klefot, J M; Murphy, J L; Donohue, K D; O'Hara, B F; Lhamon, M E; Bewley, J M

    2016-10-01

    Limited research has been conducted to assess sleep in production livestock primarily because of limitations with monitoring capabilities. Consequently, biological understanding of production circumstances and facility options that affect sleep is limited. The objective of this study was to assess if data collected from a proof-of-concept, noninvasive 3-axis accelerometer device are correlated with sleep and wake-like behaviors in dairy cattle. Four Holstein dairy cows housed at the University of Kentucky Coldstream Dairy in September 2013 were visually observed for 2 consecutive 24-h periods. The accelerometer device was attached to a harness positioned on the right side of each cow's neck. Times of classified behaviors of wake (standing, head up, alert, eyes open) or sleep-like behaviors (lying, still, head resting on ground, eyes closed) were recorded continuously by 2 observers who each watched 2 cows at a time. The radial signal was extracted from 3 different axes of the accelerometer to obtain a motion signal independent of direction of movement. Radial signal features were examined for maximizing the performance of detecting sleep-like behaviors using a Fisher's linear discriminant analysis classifier. The study included 652min of high-activity wake behaviors and 107min of sleep-like behavior among 4 cows. Results from a bootstrapping analysis showed an agreement between human observation and the linear discriminant analysis classifier, with an accuracy of 93.7±0.7% for wake behavior and 92.2±0.8% for sleep-like behavior (±95% confidence interval).This prototype shows promise in measuring sleep-like behaviors. Improvements to both hardware and software should allow more accurate determinations of subtle head movements and respiratory movements that will further improve the assessment of these sleep-like behaviors, including estimates of deep, light, and rapid eye movement sleep. These future studies will require simultaneous electroencephalography and

  7. Factors affecting dairy farmers' attitudes towards antimicrobial medicine usage in cattle in England and Wales.

    PubMed

    Jones, P J; Marier, E A; Tranter, R B; Wu, G; Watson, E; Teale, C J

    2015-09-01

    There has been growing concern about bacterial resistance to antimicrobials in the farmed livestock sector. Attention has turned to sub-optimal use of antimicrobials as a driver of resistance. Recent reviews have identified a lack of data on the pattern of antimicrobial use as an impediment to the design of measures to tackle this growing problem. This paper reports on a study that explored use of antibiotics by dairy farmers and factors influencing their decision-making around this usage. We found that respondents had either recently reduced their use of antibiotics, or planned to do so. Advice from their veterinarian was instrumental in this. Over 70% thought reducing antibiotic usage would be a good thing to do. The most influential source of information used was their own veterinarian. Some 50% were unaware of the available guidelines on use in cattle production. However, 97% thought it important to keep treatment records. The Theory of Planned Behaviour was used to identify dairy farmers' drivers and barriers to reduce use of antibiotics. Intention to reduce usage was weakly correlated with current and past practice of antibiotic use, whilst the strongest driver was respondents' belief that their social and advisory network would approve of them doing this. The higher the proportion of income from milk production and the greater the chance of remaining in milk production, the significantly higher the likelihood of farmers exhibiting positive intention to reduce antibiotic usage. Such farmers may be more commercially minded than others and thus more cost-conscious or, perhaps, more aware of possible future restrictions. Strong correlation was found between farmers' perception of their social referents' beliefs and farmers' intent to reduce antibiotic use. Policy makers should target these social referents, especially veterinarians, with information on the benefits from, and the means to, achieving reductions in antibiotic usage. Information on sub-optimal use

  8. Potential uses of cloning in breeding schemes: dairy cattle.

    PubMed

    Bousquet, D; Blondin, P

    2004-01-01

    Cloning by nuclear transfer has many potential applications in a dairy cattle breeding program. It can be used to increase the accuracy of selection and therefore the rate of genetic progress, to speed up the dissemination of the genes from animals of exceptionally high genetic merit to the commercial population, and to reproduce transgenic animals. Today, however, the main limitation of the use of cloning besides governmental regulations is its low success rate and consequently the high cost to produce an animal ready for reproduction. As a result cloning is mostly limited to the reproduction of animals of very high genetic merit or that carry genes of specific interest. Examples of this are top-ranked bulls which do not produce enough semen for the demand due to various reasons. A strategy that could be used by artificial insemination (AI) centers would be to create a bank of somatic cells for every bull entering AI facilities long before they are placed on the young sire proving program. The other use of cloning is to assist in the selection and reproduction of bull dams. Marker assisted selection (MAS) can substantially enhance the accuracy of selection for embryos or young animals without comprehensive performance records, and therefore can greatly increase the value of cloning such embryos or young animals.

  9. Frictional forces required for unrestrained locomotion in dairy cattle.

    PubMed

    van der Tol, P P J; Metz, J H M; Noordhuizen-Stassen, E N; Back, W; Braam, C R; Weijs, W A

    2005-02-01

    Most free-stall housing systems in the Netherlands are equipped with slatted or solid concrete floors with manure scrapers. A slipping incident occurs when the required coefficient of friction (RCOF) exceeds the coefficient of friction (COF) at the claw-floor interface. An experiment was conducted to measure ground reaction forces (GRF) of dairy cows (n = 9) performing various locomotory behaviors on a nonslippery rubber-covered concrete floor. The RCOF was determined as the ratio of the horizontal and vertical components of the GRF. It was shown that during straight walking and walking-a-curve, the RCOF reached values up to the COF, whereas for sudden stop-and-start responses, the RCOF reached values beyond the maximum COF that concrete floors can provide. Our results indicate that concrete floors do not provide enough friction to allow natural locomotory behavior and suggest that tractional properties of floors should be main design criteria in the development of better flooring surfaces for cattle.

  10. Potential uses of cloning in breeding schemes: dairy cattle.

    PubMed

    Bousquet, D; Blondin, P

    2004-01-01

    Cloning by nuclear transfer has many potential applications in a dairy cattle breeding program. It can be used to increase the accuracy of selection and therefore the rate of genetic progress, to speed up the dissemination of the genes from animals of exceptionally high genetic merit to the commercial population, and to reproduce transgenic animals. Today, however, the main limitation of the use of cloning besides governmental regulations is its low success rate and consequently the high cost to produce an animal ready for reproduction. As a result cloning is mostly limited to the reproduction of animals of very high genetic merit or that carry genes of specific interest. Examples of this are top-ranked bulls which do not produce enough semen for the demand due to various reasons. A strategy that could be used by artificial insemination (AI) centers would be to create a bank of somatic cells for every bull entering AI facilities long before they are placed on the young sire proving program. The other use of cloning is to assist in the selection and reproduction of bull dams. Marker assisted selection (MAS) can substantially enhance the accuracy of selection for embryos or young animals without comprehensive performance records, and therefore can greatly increase the value of cloning such embryos or young animals. PMID:15268795

  11. Circadian rhythm of aldosterone in dairy cattle during the summer

    NASA Astrophysics Data System (ADS)

    Aranas, T. J.; Roussel, J. D.; Seybt, S. H.

    1987-09-01

    Twelve Holstein heifers, pregnant from 120 150 days were used to study the circadian rhythm of aldosterone, cortisol, progesterone, sodium and potassium in dairy cattle during the summer in Louisiana. Cortisol was not significantly influenced by time (time 1 = 06.00 h). Aldosterone, sodium, potassium and progesterone changed significantly (P<.01) with time. Aldosterone peaked (116.5±17.2 pg/ml) at 08.00 h and then generally declined to 16.00 h (26.7±2.0 pg/ml). Sodium generally increased from 06.00 h (320.1±7.3 mg%) to 18.00 h (377.9±6.1 mg%), and then declined. Potassium generally increased from 06.00 h (20.9±0.5 mg%) to 22.00 h (23.0±0.3 mg%). Progesterone generally increased from 07.00 h (2.8±0.4 mg/ml) to 24.00 h (7.5±1.4 mg/ml). Aldosterone was significantly related to temperature associated with the time of the day samples were taken (r = 0.66, P<.02).

  12. Distribution of coagulase-negative Staphylococcus species from milk and environment of dairy cows differs between herds.

    PubMed

    Piessens, V; Van Coillie, E; Verbist, B; Supré, K; Braem, G; Van Nuffel, A; De Vuyst, L; Heyndrickx, M; De Vliegher, S

    2011-06-01

    In many parts of the world, coagulase-negative staphylococci (CNS) are the predominant pathogens causing intramammary infections (IMI) in dairy cows. The cows' environment is thought to be a possible source for CNS mastitis and this was investigated in the present paper. A longitudinal field study was carried out in 6 well-managed dairy herds to determine the distribution and epidemiology of various CNS species isolated from milk, causing IMI and living freely in the cows' environment, respectively. In each herd, quarter milk samples from a cohort of 10 lactating cows and environmental samples from stall air, slatted floor, sawdust from cubicles, and sawdust stock were collected monthly (n=13). Isolates from quarter milk samples (n=134) and the environment (n=637) were identified to species level using amplified fragment length polymorphism (AFLP) genotyping. Staphylococcus chromogenes, S. haemolyticus, S. epidermidis, and S. simulans accounted for 81.3% of all CNS milk isolates. Quarters were considered infected with CNS (positive IMI status) only when 2 out of 3 consecutive milk samples yielded the same CNS AFLP type. The species causing IMI were S. chromogenes (n=35 samples with positive IMI status), S. haemolyticus (n=29), S. simulans (n=14), and S. epidermidis (n=6). The observed persistent IMI cases (n=17) had a mean duration of 149.4 d (range 63.0 to 329.8 d). The CNS species predominating in the environment were S. equorum, S. sciuri, S. haemolyticus, and S. fleurettii. Herd-to-herd differences in distribution of CNS species were observed in both milk and the environment, suggesting that herd-level factors are involved in the establishment of particular species in a dairy herd. Primary reservoirs of the species causing IMI varied. Staphylococcus chromogenes and S. epidermidis were rarely found in the environment, indicating that other reservoirs were more important in their epidemiology. For S. haemolyticus and S. simulans, the environment was found as a

  13. Association of oxidative status and insulin sensitivity in periparturient dairy cattle: an observational study.

    PubMed

    Abuelo, A; Hernández, J; Benedito, J L; Castillo, C

    2016-04-01

    Post-parturient insulin resistance (IR) is a common feature in all mammalian animals. However, in dairy cows, it can be exacerbated because of high milk yield, leading to excessive negative energy balance, which is related with increased disease incidence, reduced milk production and worsened reproductive performance. IR has been extensively investigated in humans suffering from diabetes mellitus. In these subjects, it is known that oxidative stress (OS) plays a causative role in the onset of IR. Although OS occurs in transitional dairy cattle, there are yet no studies that investigated the association between IR and OS in dairy cattle. Therefore, the aim of this study was to investigate whether there is a relationship between OS and IR in dairy cattle. Serum samples were taken repeatedly from 22 dairy cows from 2 months prior to the expected calving date to 2 months after calving and were analysed for markers of metabolic and redox balance. Surrogate indices of insulin sensitivity were also calculated. Generalised linear mixed models revealed an effect of the oxidative status on peripheral insulin concentration and on indices of insulin sensitivity. Hence, field trials should investigate the effectiveness of antioxidant therapy on insulin sensitivity in peripheral tissues during the transition period of dairy cattle.

  14. Factors associated with high milk test day somatic cell counts in large dairy herds in Brandenburg. I: Housing conditions.

    PubMed

    Köster, G; Tenhagen, B-A; Heuwieser, W

    2006-04-01

    The aim of this study was to examine influences of housing conditions on the udder health in 80 German dairy herds with a herd size between 100 and 1100 cows. Data were collected using a standardized questionnaire for the farm manager and a farm visit using a standardized data capture form on hygiene and management. The somatic cell counts of all lactating cows on each farm were collected monthly by the local dairy herd improvement association and analysed to assess udder health status. Factor analysis was used to analyse the variables describing the environmental hygiene. The values derived for the extracted components were classified into good, moderate and poor. The association of the categories was then analysed for their influence on log somatic cell count of the current month (CMSCC) and the year before the farm visit (YASCC) by a one-way anova. In comparison to other housing systems, free stalls with cubicles had the lowest geometric mean somatic cell count. Three components were derived from the factor analysis. Of those, acceptance of the cubicles by the cows and barn hygiene were determined as components influencing the CMSCC and YASCC significantly, while the association of hygiene of the milking parlour with somatic cell counts was only significant for YASCC. The results of the study show that the cow comfort and housing hygiene have a substantial impact on milk quality and should therefore become the focus of further research on the farm management practices.

  15. Use of crossbreeding with beef bulls in dairy herds: effect on age, body weight, price, and market value of calves sold at livestock auctions.

    PubMed

    Dal Zotto, R; Penasa, M; De Marchi, M; Cassandro, M; López-Villalobos, N; Bittante, G

    2009-09-01

    The aim of this study was to investigate the effect of different breeds and breed crosses on age (AC, d), BW (kg), price (PR, $/kg), and market value (MV, $/calf) of purebred and crossbred calves sold for veal and beef production. The Kovieh wholesale cattle organization (Bolzano, Italy) grouped calves from several dairy herds located in the Trentino-Südtirol region in Italy and sold them by public auctions. Data on AC, BW, PR, and MV from 96,458 calves were recorded from January 2003 to December 2007 and consisted of 4 pure breeds [2 dairy, Brown Swiss (BS) and Holstein-Friesian (HF); and 2 dual-purpose, Simmental (SI) and Alpine Grey (AG)], and 8 crossbreds by crosses of Limousin (LI) and Belgian Blue (BB) with the 4 dam breeds. Least squares means for AC, BW, PR, and MV were calculated for breeds and breed crosses with a model that included fixed effects of herd of birth, age (except for AC), sex, and breed of the calf, year and season of auction, and interactions between the main effects. The coefficients of determination of the models were 0.41, 0.51, 0.84, and 0.82 for AC, BW, PR, and MV, respectively. Sex, age, and breed were the most relevant sources of variation for BW (P < 0.001), whereas breed and sex were the most important sources of variation for AC, PR, and MV (P < 0.001). Also, PR and MV were significantly influenced (P < 0.01) by all the effects included in the model, except for season x age interaction in the case of MV. Market value of male was greater (P < 0.001) than that of female calves, with the exception of BS (-$28.76/calf) and HF (-$20.70/calf) purebred males. Dual-purpose purebred calves presented greater (P < 0.001) PR and MV than dairy purebreds (MV of $426.97/calf and $307.96/calf for SI and AG, and $256.24/calf and $275.65/calf for BS and HF, respectively). Calves from SI and AG dams had greater (P < 0.001) BW, PR, and MV than calves from BS and HF dams. Calves from SI cows had greater (P < 0.001) BW, PR, and MV than calves from AG

  16. Congenital cataracts in an Ayrshire herd: a herd case report

    PubMed Central

    2014-01-01

    An Ayrshire dairy herd was investigated for occurrence of ocular abnormalities in new-born calves. Ophthalmic examinations were performed on all the animals in the herd and 26% of them were diagnosed with bilateral cataracts. Cataracts varied in extent and severity but the majority were restricted to the lens nucleus. Epidemiological analysis showed the prevalence was higher in male animals and lower in animals born to heifers. A family tree was designed but no genetic impact of dam lines was evident. Sire data was incomplete and could therefore not be included. Based on the information provided by the farmer there was no obvious environmental or nutritional cause of these cataracts. However, data records were incomplete and further investigation/monitoring of the herd would be needed to establish a cause and enable a better insight into the aetiology of this disease in cattle. PMID:24460638

  17. Cattle on pastures do align along the North-South axis, but the alignment depends on herd density.

    PubMed

    Slaby, P; Tomanova, K; Vacha, M

    2013-08-01

    Alignment is a spontaneous behavioral preference of particular body orientation that may be seen in various vertebrate or invertebrate taxa. Animals often optimize their positions according to diverse directional environmental factors such as wind, stream, slope, sun radiation, etc. Magnetic alignment represents the simplest directional response to the geomagnetic field and a growing body of evidence of animals aligning their body positions according to geomagnetic lines whether at rest or during feedings is accumulating. Recently, with the aid of Google Earth application, evidence of prevailing North-South (N-S) body orientation of cattle on pastures was published (Begall et al. PNAS 105:13451-13455, 2008; Burda et al. PNAS 106:5708-5713, 2009). Nonetheless, a subsequent study from a different laboratory did not confirm this phenomenon (Hert et al. J Comp Physiol A 197:677-682, 2011). The aim of our study was to enlarge the pool of independently gained data on this remarkable animal behavior. By satellite snapshots analysis and using blinded protocol we scored positions of 2,235 individuals in 74 herds. Our results are in line with the original findings of prevailing N-S orientation of grazing cattle. In addition, we found that mutual distances between individual animals within herds (herd density) affect their N-S preference-a new phenomenon giving some insight into biological significance of alignment. PMID:23700176

  18. The effect of calf nutrition on the performance of dairy herd replacements.

    PubMed

    Morrison, S J; Wicks, H C F; Carson, A F; Fallon, R J; Twigge, J; Kilpatrick, D J; Watson, S

    2012-06-01

    Sixty-five Holstein-Friesian calves were randomly allocated to one of eight nutritional treatments at 4 days of age. In this factorial design study, the treatments comprised of four levels of milk replacer (MR) mixed in 6 l of water (500, 750, 1000 and 1250 g/day) × two crude protein (CP) concentrations (230 and 270 g CP/kg dry matter (DM)). MR was fed via automatic teat feeders and concentrates were offered via automated dispensers during the pre-wean period. MR and calf starter concentrate intake were recorded until weaning with live weight and body measurements recorded throughout the rearing period until heifers entered the dairy herd at a targeted 24 months of age. There was no effect of MR protein concentration on concentrate or MR intake, and no effect on body size or live weight at any stage of development. During the pre-weaning period, for every 100 g increase in MR allowance, concentrate consumption was reduced by 39 g/day. While, for every 100 g increase in the amount of MR offered, live weight at days 28 and 270 increased by 0.76 and 2.61 kg, respectively (P < 0.05). Increasing MR feed levels increased (P < 0.05) heart girth and body condition score at recordings during the first year of life, but these effects disappeared thereafter. Increasing MR feeding level tended to reduce both age at first observed oestrus and age at first service but no significant effect on age at first calving was observed. Neither MR feeding level nor MR CP content affected post-calving live weight or subsequent milk production. Balance measurements conducted using 44 male calves during the pre-weaning period showed that increasing milk allowance increased energy and nitrogen (N) intake, diet DM digestibility, true N digestibility and the biological value of the dietary protein. Increasing the MR protein content had no significant effect on the apparent digestibility of N or DM.

  19. Genome-Wide Diversity and Phylogeography of Mycobacterium avium subsp. paratuberculosis in Canadian Dairy Cattle

    PubMed Central

    Ahlstrom, Christina; Barkema, Herman W.; Stevenson, Karen; Zadoks, Ruth N.; Biek, Roman; Kao, Rowland; Trewby, Hannah; Haupstein, Deb; Kelton, David F.; Fecteau, Gilles; Labrecque, Olivia; Keefe, Greg P.; McKenna, Shawn L. B.; Tahlan, Kapil; De Buck, Jeroen

    2016-01-01

    Mycobacterium avium subsp. paratuberculosis (MAP) is the causative bacterium of Johne’s disease (JD) in ruminants. The control of JD in the dairy industry is challenging, but can be improved with a better understanding of the diversity and distribution of MAP subtypes. Previously established molecular typing techniques used to differentiate MAP have not been sufficiently discriminatory and/or reliable to accurately assess the population structure. In this study, the genetic diversity of 182 MAP isolates representing all Canadian provinces was compared to the known global diversity, using single nucleotide polymorphisms identified through whole genome sequencing. MAP isolates from Canada represented a subset of the known global diversity, as there were global isolates intermingled with Canadian isolates, as well as multiple global subtypes that were not found in Canada. One Type III and six “Bison type” isolates were found in Canada as well as one Type II subtype that represented 86% of all Canadian isolates. Rarefaction estimated larger subtype richness in Québec than in other Canadian provinces using a strict definition of MAP subtypes and lower subtype richness in the Atlantic region using a relaxed definition. Significant phylogeographic clustering was observed at the inter-provincial but not at the intra-provincial level, although most major clades were found in all provinces. The large number of shared subtypes among provinces suggests that cattle movement is a major driver of MAP transmission at the herd level, which is further supported by the lack of spatial clustering on an intra-provincial scale. PMID:26871723

  20. Economic comparison of common treatment protocols and J5 vaccination for clinical mastitis in dairy herds using optimized culling decisions.

    PubMed

    Kessels, J A; Cha, E; Johnson, S K; Welcome, F L; Kristensen, A R; Gröhn, Y T

    2016-05-01

    This study used an existing dynamic optimization model to compare costs of common treatment protocols and J5 vaccination for clinical mastitis in US dairy herds. Clinical mastitis is an infection of the mammary gland causing major economic losses in dairy herds due to reduced milk production, reduced conception, and increased risk of mortality and culling for infected cows. Treatment protocols were developed to reflect common practices in dairy herds. These included targeted therapy following pathogen identification, and therapy without pathogen identification using a broad-spectrum antimicrobial or treating with the cheapest treatment option. The cost-benefit of J5 vaccination was also estimated. Effects of treatment were accounted for as changes in treatment costs, milk loss due to mastitis, milk discarded due to treatment, and mortality. Following ineffective treatments, secondary decisions included extending the current treatment, alternative treatment, discontinuing treatment, and pathogen identification followed by recommended treatment. Average net returns for treatment protocols and vaccination were generated using an existing dynamic programming model. This model incorporates cow and pathogen characteristics to optimize management decisions to treat, inseminate, or cull cows. Of the treatment protocols where 100% of cows received recommended treatment, pathogen-specific identification followed by recommended therapy yielded the highest average net returns per cow per year. Out of all treatment scenarios, the highest net returns were achieved with selecting the cheapest treatment option and discontinuing treatment, or alternate treatment with a similar spectrum therapy; however, this may not account for the full consequences of giving nonrecommended therapies to cows with clinical mastitis. Vaccination increased average net returns in all scenarios.

  1. Ammonia emissions from naturally ventilated dairy cattle buildings and outdoor concrete yards in Portugal

    NASA Astrophysics Data System (ADS)

    Pereira, José; Misselbrook, Tom H.; Chadwick, David R.; Coutinho, João; Trindade, Henrique

    2010-09-01

    There is a lack of information on ammonia (NH 3) emissions from cattle housing systems in Mediterranean countries, with most published data deriving from NW Europe. An investigation was carried out in NW Portugal to quantify NH 3 emissions for the main types of dairy cattle buildings in Portugal, i.e. naturally ventilated buildings and outdoor concrete yards, and to derive robust emission factors (EFs) for these conditions and compare with EFs used elsewhere in Europe. Measurements were made throughout a 12-month period using the passive flux sampling method in the livestock buildings and the equilibrium concentration technique in outdoor yards. The mean NH 3 emission factor for the whole housing system (buildings + outdoor yards) was 43.7 g NH 3-N LU -1 day -1 and for outdoor concrete yards used by dairy cattle was 26.6 g NH 3-N LU -1 day -1. Expressing NH 3 emission in terms of the quantity of liquid milk produced gave similar values across the three dairy farms studied (with a mean of 2.3 kg N ton-milk -1 produced) and may have advantages when comparing different farming systems. In dairy houses with outdoor yards, NH 3 emissions from the yard area contributed to 69-92% of total emissions from this housing system. Emissions were particularly important during spring and summer seasons from outdoor yards with NH 3 emitted in this period accounting for about 72% of annual emissions from outdoor yards. Mean NH 3 emission factors derived for this freestall housing system and outdoor concrete yards used by dairy cattle in Portugal were higher than those measured in northern Europe. In addition, values of animal N excretion estimated in this study were greater than official National standard values. If these emissions are typical for Portuguese dairy systems, then the current National inventory underestimates emissions from this source in NW of Portugal, because of the use of lower standard values of N excretion by dairy cattle.

  2. The use of multilevel models to evaluate sources of variation in reproductive performance in dairy cattle in Reunion Island.

    PubMed

    Dohoo, I R; Tillard, E; Stryhn, H; Faye, B

    2001-07-19

    Sources of variation in measures of reproductive performance in dairy cattle were evaluated using data collected from 3207 lactations in 1570 cows in 50 herds from five geographic regions of Reunion Island (located off the east coast of Madagascar). Three continuously distributed reproductive parameters (intervals from calving-to-conception, calving-to-first-service and first-service-to-conception) were considered, along with one Binomial outcome (first-service-conception risk). Multilevel models which take into account the hierarchical nature of the data were used to fit all models. For the overall measure of calving-to-conception interval, 86% of the variation resided at the lactation level with only 7, 6 and 2% at the cow, herd and regional levels, respectively. The proportion of variance at the herd and cow levels were slightly higher for the calving-to-first-service interval (12 and 9%, respectively) - but for the other two parameters (first-service-conception risk and first-service-to-conception interval), >90% of the variation resided at the lactation level. For the three continuous dependent variables, comparison of results between models based on log-transformed data and Box-Cox-transformed data suggested that minor departures from the assumption of normality did not have a substantial effect on the variance estimates. For the Binomial dependent variable, five different estimation procedures (penalised quasi-likelihood, Markov-Chain Monte Carlo, parametric and non-parametric bootstrap estimates and maximum-likelihood) yielded substantially different results for the estimate of the cow-level variance.

  3. Eradication of bovine tuberculosis at a herd-level in Madrid, Spain: study of within-herd transmission dynamics over a 12 year period

    PubMed Central

    2012-01-01

    Background Eradication of bovine tuberculosis (bTB) through the application of test-and-cull programs is a declared goal of developed countries in which the disease is still endemic. Here, longitudinal data from more than 1,700 cattle herds tested during a 12 year-period in the eradication program in the region of Madrid, Spain, were analyzed to quantify the within-herd transmission coefficient (β) depending on the herd-type (beef/dairy/bullfighting). In addition, the probability to recover the officially bTB free (OTF) status in infected herds depending on the type of herd and the diagnostic strategy implemented was assessed using Cox proportional hazard models. Results Overall, dairy herds showed higher β (median 4.7) than beef or bullfighting herds (2.3 and 2.2 respectively). Introduction of interferon-gamma (IFN-γ) as an ancillary test produced an apparent increase in the β coefficient regardless of production type, likely due to an increase in diagnostic sensitivity. Time to recover OTF status was also significantly lower in dairy herds, and length of bTB episodes was significantly reduced when the IFN-γ was implemented to manage the outbreak. Conclusions Our results suggest that bTB spreads more rapidly in dairy herds compared to other herd types, a likely cause being management and demographic-related factors. However, outbreaks in dairy herds can be controlled more rapidly than in typically extensive herd types. Finally, IFN-γ proved its usefulness to rapidly eradicate bTB at a herd-level. PMID:22748007

  4. Schmallenberg virus epidemic: impact on milk production, reproductive performance and mortality in dairy cattle in the Netherlands and Kleve district, Germany.

    PubMed

    Veldhuis, A M B; Santman-Berends, I M G A; Gethmann, J M; Mars, M H; van Wuyckhuise, L; Vellema, P; Holsteg, M; Höreth-Böntgen, D; Conraths, F J; van Schaik, G

    2014-10-15

    Schmallenberg virus (SBV), a novel orthobunyavirus that rapidly spread throughout north-western Europe in 2011, caused congenital malformations in lambs and goat kids (Van den Brom et al., 2012) and newborn calves (Hoffmann et al., 2012). The impact of the SBV epidemic seemed limited however, in terms of the number of affected herds with malformed offspring (European Food Safety Authority, 2012b). Nevertheless, little is known with regard to the overall within-herd impact of SBV infection. The objective of the current study was to quantify the impact of the 2011 SBV epidemic on the productivity of dairy cattle in the Netherlands and the district of Kleve, Germany. For the Netherlands, several multilevel multivariable statistical models were applied on eight productivity parameters regarding milk production, reproductive performance and mortality. All four fertility parameters analysed were slightly but significantly reduced between August 1st and November 1st 2011 compared to the reference period in 2009-2010. Between August 15th and September 19th 2011, the average loss in milk production per cow was -0.26kg (95% CI: -0.30; -0.22) per day in dairy herds, compared to the reference period (p<0.001). The total loss per cow in a subgroup of dairy herds that notified malformations in newborn calves during the mandatory notification period in the Netherlands was -0.43kg (95% CI: -0.59; -0.28) per day (p<0.001). For Germany, a study was carried out in the district of Kleve, situated in the state of North Rhine-Westphalia near the Dutch border. Data on milk yield, two fertility parameters and the number of rendered calves in this specific region were analysed. There was a small but significant increase in the number of secondary and third inseminations between August 1st and November 1st 2011, indicating reduced fertility. No significant change in calf mortality was observed in the assumed SBV period. Milk production at district level did not seem to be affected by SBV in

  5. Genetic Structure of Mycobacterium avium subsp. paratuberculosis Population in Cattle Herds in Quebec as Revealed by Using a Combination of Multilocus Genomic Analyses

    PubMed Central

    Sohal, Jagdip Singh; Arsenault, Julie; Labrecque, Olivia; Fairbrother, Julie-Hélène; Roy, Jean-Philippe; Fecteau, Gilles

    2014-01-01

    Mycobacterium avium subsp. paratuberculosis is the etiological agent of paratuberculosis, a granulomatous enteritis affecting a wide range of domestic and wild ruminants worldwide. A variety of molecular typing tools are used to distinguish M. avium subsp. paratuberculosis strains, contributing to a better understanding of M. avium subsp. paratuberculosis epidemiology. In the present study, PCR-based typing methods, including mycobacterial interspersed repetitive units/variable-number tandem repeats (MIRU-VNTR) and small sequence repeats (SSR) in addition to IS1311 PCR-restriction enzyme analysis (PCR-REA), were used to investigate the genetic heterogeneity of 200 M. avium subsp. paratuberculosis strains from dairy herds located in the province of Quebec, Canada. The majority of strains were of the “cattle type,” or type II, although 3 strains were of the “bison type.” A total of 38 genotypes, including a novel one, were identified using a combination of 17 genetic markers, which generated a Simpson's index of genetic diversity of 0.876. Additional analyses revealed no differences in genetic diversity between environmental and individual strains. Of note, a spatial and spatiotemporal cluster was evidenced regarding the distribution of one of the most common genotypes. The population had an overall homogeneous genetic structure, although a few strains stemmed out of the consensus cluster, including the bison-type strains. The genetic structure of M. avium subsp. paratuberculosis populations within most herds suggested intraherd dissemination and microevolution, although evidence of interherd contamination was also revealed. The level of genetic diversity obtained by combining MIRU-VNTR and SSR markers shows a promising avenue for molecular epidemiology investigations of M. avium subsp. paratuberculosis transmission patterns. PMID:24829229

  6. Genetic structure of Mycobacterium avium subsp. paratuberculosis population in cattle herds in Quebec as revealed by using a combination of multilocus genomic analyses.

    PubMed

    Sohal, Jagdip Singh; Arsenault, Julie; Labrecque, Olivia; Fairbrother, Julie-Hélène; Roy, Jean-Philippe; Fecteau, Gilles; L'Homme, Yvan

    2014-08-01

    Mycobacterium avium subsp. paratuberculosis is the etiological agent of paratuberculosis, a granulomatous enteritis affecting a wide range of domestic and wild ruminants worldwide. A variety of molecular typing tools are used to distinguish M. avium subsp. paratuberculosis strains, contributing to a better understanding of M. avium subsp. paratuberculosis epidemiology. In the present study, PCR-based typing methods, including mycobacterial interspersed repetitive units/variable-number tandem repeats (MIRU-VNTR) and small sequence repeats (SSR) in addition to IS1311 PCR-restriction enzyme analysis (PCR-REA), were used to investigate the genetic heterogeneity of 200 M. avium subsp. paratuberculosis strains from dairy herds located in the province of Quebec, Canada. The majority of strains were of the "cattle type," or type II, although 3 strains were of the "bison type." A total of 38 genotypes, including a novel one, were identified using a combination of 17 genetic markers, which generated a Simpson's index of genetic diversity of 0.876. Additional analyses revealed no differences in genetic diversity between environmental and individual strains. Of note, a spatial and spatiotemporal cluster was evidenced regarding the distribution of one of the most common genotypes. The population had an overall homogeneous genetic structure, although a few strains stemmed out of the consensus cluster, including the bison-type strains. The genetic structure of M. avium subsp. paratuberculosis populations within most herds suggested intraherd dissemination and microevolution, although evidence of interherd contamination was also revealed. The level of genetic diversity obtained by combining MIRU-VNTR and SSR markers shows a promising avenue for molecular epidemiology investigations of M. avium subsp. paratuberculosis transmission patterns. PMID:24829229

  7. Characterising the bacterial microbiota across the gastrointestinal tracts of dairy cattle: membership and potential function

    PubMed Central

    Mao, Shengyong; Zhang, Mengling; Liu, Junhua; Zhu, Weiyun

    2015-01-01

    The bacterial community composition and function in the gastrointestinal tracts (GITs) of dairy cattle is very important, since it can influence milk production and host health. However, our understanding of bacterial communities in the GITs of dairy cattle is still very limited. This study analysed bacterial communities in ten distinct GIT sites (the digesta and mucosa of the rumen, reticulum, omasum, abomasum, duodenum, jejunum, ileum, cecum, colon and rectum) in six dairy cattle. The study observed 542 genera belonging to 23 phyla distributed throughout the cattle GITs, with the Firmicutes, Bacteroidetes and Proteobacteria predominating. In addition, data revealed significant spatial heterogeneity in composition, diversity and species abundance distributions of GIT microbiota. Furthermore, the study inferred significant differences in the predicted metagenomic profiles among GIT regions. In particular, the relative abundances of the genes involved in carbohydrate metabolism were overrepresented in the digesta samples of forestomaches, and the genes related to amino acid metabolism were mainly enriched in the mucosal samples. In general, this study provides the first deep insights into the composition of GIT microbiota in dairy cattle, and it may serve as a foundation for future studies in this area. PMID:26527325

  8. Characterising the bacterial microbiota across the gastrointestinal tracts of dairy cattle: membership and potential function.

    PubMed

    Mao, Shengyong; Zhang, Mengling; Liu, Junhua; Zhu, Weiyun

    2015-01-01

    The bacterial community composition and function in the gastrointestinal tracts (GITs) of dairy cattle is very important, since it can influence milk production and host health. However, our understanding of bacterial communities in the GITs of dairy cattle is still very limited. This study analysed bacterial communities in ten distinct GIT sites (the digesta and mucosa of the rumen, reticulum, omasum, abomasum, duodenum, jejunum, ileum, cecum, colon and rectum) in six dairy cattle. The study observed 542 genera belonging to 23 phyla distributed throughout the cattle GITs, with the Firmicutes, Bacteroidetes and Proteobacteria predominating. In addition, data revealed significant spatial heterogeneity in composition, diversity and species abundance distributions of GIT microbiota. Furthermore, the study inferred significant differences in the predicted metagenomic profiles among GIT regions. In particular, the relative abundances of the genes involved in carbohydrate metabolism were overrepresented in the digesta samples of forestomaches, and the genes related to amino acid metabolism were mainly enriched in the mucosal samples. In general, this study provides the first deep insights into the composition of GIT microbiota in dairy cattle, and it may serve as a foundation for future studies in this area. PMID:26527325

  9. Livestock-Associated Methicillin Resistant and Methicillin Susceptible Staphylococcus aureus Sequence Type (CC)1 in European Farmed Animals: High Genetic Relatedness of Isolates from Italian Cattle Herds and Humans

    PubMed Central

    Alba, Patricia; Feltrin, Fabiola; Cordaro, Gessica; Porrero, María Concepción; Kraushaar, Britta; Argudín, María Angeles; Nykäsenoja, Suvi; Monaco, Monica; Stegger, Marc; Aarestrup, Frank M.; Butaye, Patrick; Franco, Alessia; Battisti, Antonio

    2015-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) Sequence Type (ST)1, Clonal Complex(CC)1, SCCmec V is one of the major Livestock-Associated (LA-) lineages in pig farming industry in Italy and is associated with pigs in other European countries. Recently, it has been increasingly detected in Italian dairy cattle herds. The aim of this study was to analyse the differences between ST1 MRSA and methicillin-susceptible S. aureus (MSSA) from cattle and pig herds in Italy and Europe and human isolates. Sixty-tree animal isolates from different holdings and 20 human isolates were characterized by pu