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Sample records for conventional dairy herds

  1. 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.

  2. 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

  3. A comparison of antimicrobial susceptibility patterns for Staphylococcus aureus in organic and conventional dairy herds.

    PubMed

    Tikofsky, Linda L; Barlow, John W; Santisteban, Carlos; Schukken, Ynte H

    2003-01-01

    Selective pressure from antimicrobial use, mutations, or acquisition of foreign resistance determinants mediate antimicrobial resistance. If antimicrobial use is the major selective pressure encouraging the development of resistance, then reduced use should result in decreased resistance. We compared antimicrobial susceptibility patterns of Staphylococcus aureus isolates obtained from milk samples from 22 organic (nonantibiotic using) dairy herds to isolates from 16 conventional dairy herds. Susceptibility testing was performed by disk diffusion, and zone diameters were recorded in millimeters for 144 isolates from organic farms and 117 isolates from conventional farms and were also classified as susceptible or not-susceptible (intermediate and resistant categories combined). Strength of association between high or low use and proportion susceptible was evaluated by Chi-square analysis and differences in mean zone diameter for isolates from organic farms versus isolates from conventional farms were compared by analysis of variance. Analysis was done for each antimicrobial and deemed significant at p < or = 0.05. Differences in antimicrobial susceptibility were observed between S. aureus isolates from organic and conventional herds for seven of the nine antibiotics studied. Herds that were certified organic had S. aureus isolates that were more susceptible to antimicrobials. Overall, S. aureus isolates from both organic and conventional herds showed good susceptibility to most commonly used bovine mastitis antimicrobials; however, isolates from organic herds were significantly more susceptible. Longitudinal studies of herds undergoing the transition to organic farming would help elucidate the dynamics of antimicrobial resistance and the potential return of antimicrobial susceptibility.

  4. Case study: Comparison of biological active compounds in milk from organic and conventional dairy herds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Conflicting reports of the quantities of biologically active compounds present in milk from organic grass-fed and conventional herds show that more research is required, especially as these compounds are linked to human health benefits and can improve the health value consumers place on dairy produc...

  5. Culling reasons in organic and conventional dairy herds and genotype by environment interaction for longevity.

    PubMed

    Ahlman, T; Berglund, B; Rydhmer, L; Strandberg, E

    2011-03-01

    Dairy cow longevity combines all functional traits and is thought to be especially important in organic production, which is an established, increasing part of Swedish dairy production, representing approximately 6% of the market. The aim of this study was to compare dynamics in culling reasons between organic and conventional production and to analyze genotype by environment interactions for longevity. The data contained information from all organic herds with information available from official recording (n=402) and from approximately half of the conventional herds (n=5,335). Records from Swedish Holsteins (n=155,379) and Swedish Red cows (n=160,794) that had their first calf between January 1998 and September 2003 were included. The opportunity period for longevity was at least 6 yr. Six longevity traits were defined: length of productive life; survival through first, second, and third lactations; fertility-determined survival; and udder health-determined survival. Twenty codes were used to describe the cause of culling, and these were divided into 8 groups: udder health, low fertility, low production, leg problems, metabolic diseases, other diseases, other specified causes, and unspecified cause. The main reason for culling cows in organic herds was poor udder health, whereas for cows in conventional herds it was low fertility. Furthermore, the shift in main culling reason from fertility, which was most common in first lactation regardless of production system, to udder health occurred at a lower age in organic production. Heritabilities and genetic correlations for the longevity traits expressed in organic and conventional herds were estimated from a bivariate animal model. The genetic correlations were close to unity (>0.88), except for fertility-determined survival in the Swedish Red breed (0.80). Heritabilities were low to moderate, and no clear pattern was identified for production system or breed. In general, the results indicate that farmers' culling

  6. Assessment of herd management on organic and conventional dairy farms in the United States.

    PubMed

    Stiglbauer, K E; Cicconi-Hogan, K M; Richert, R; Schukken, Y H; Ruegg, P L; Gamroth, M

    2013-02-01

    The objective of this study was to evaluate management characteristics on organic and similarly sized conventional dairy farms located in New York, Wisconsin, and Oregon. Data from 192 organic farms (ORG), 64 conventional nongrazing farms (CON-NG), and 36 conventional grazing farms (CON-GR) were collected during farm visits and were size-matched and analyzed. The average lactation number of animals on ORG and CON-GR farms was 2.6 lactations, which was greater than that on CON-NG farms (2.3 lactations). A greater percentage of first-lactation heifers were found on conventional farms than on ORG farms. Facilities used by adult animals, including housing and milking facilities, did not differ among the grazing systems. Cattle on conventional farms were fed approximately twice as much grain as cattle on ORG farms and had greater milk production. Little difference was found for the average reported somatic cell count and standard plate count, suggesting that milk quality is not dependent on grazing system. Milking procedures were similar across all 3 grazing systems, indicating that an industry standard now exists for milking and that milk quality problems will need to be addressed with other management problems in mind. Although some disease prevention measures were commonly utilized on ORG farms, such as keeping a closed herd and having a written record of treatments administered to the animals, the use of outside support and vaccinations were found to be less prevalent on organic farms than on conventional farms.

  7. Conventional identification of Streptococcus uberis isolated from bovine mastitis in Argentinean dairy herds.

    PubMed

    Odierno, L; Calvinho, L; Traverssa, P; Lasagno, M; Bogni, C; Reinoso, E

    2006-10-01

    The objective of this study was to evaluate a conventional scheme for identifying Streptococcus uberis strains isolated from bovine mastitis. Seventy-five gram-positive, catalase-negative cocci were collected from cows with mastitis from 19 dairy herds located in the east-central region of Argentina. Five American Type Culture Collection strains and bovine isolates were identified by the API 20 Strep system and by restriction fragment length polymorphism analysis of 16S rDNA. A conventional scheme based on 11 biochemical tests was selected for identification of Strep. uberis strains: the Christie-Atkins-Munch-Petersen reaction; hydrolysis of Arg, esculin, and sodium hippurate; growth in inulin, mannitol, raffinose, salicin, and sorbitol; and growth at 45 degrees C and in 6.5% NaCl. Reference strains and 25 bovine isolates were classified accurately to the species level by the conventional scheme in a blind assay. Each reference strain and each bovine isolate were identified as belonging to the same species following these 3 methods. The remaining 50 isolates identified as Strep. uberis by the API 20 Strep system and 16S rDNA RFLP were assayed by the conventional scheme. This scheme correctly identified 47 (94%) of 50 isolates as Strep. uberis by comparing their biochemical profile with that of the reference strain. Three (6%) of the 50 isolates were classified as Strep. uberis by the API 20 Strep system and by 16S rDNA RFLP and were identified as Enterococcus faecalis by the conventional scheme. Thirty percent of the Strep. uberis strains showed biochemical profiles identical to the Strep. uberis American Type Culture Collection 27958 strain. Seventy percent of the Strep. uberis strains demonstrated variability compared with the reference strain, resulting in 19 different biochemical profiles. The conventional scheme proposed in this study resulted in a relatively low number of misidentifications and could biochemically identify not only typical, but also atypical

  8. Comparison of Prevalence and Antimicrobial Susceptibilities of Campylobacter spp. Isolates from Organic and Conventional Dairy Herds in Wisconsin

    PubMed Central

    Sato, K.; Bartlett, P. C.; Kaneene, J. B.; Downes, F. P.

    2004-01-01

    The prevalence and antimicrobial susceptibilities of Campylobacter spp. isolates from bovine feces were compared between organic and conventional dairy herds. Thirty organic dairy herds, where antimicrobials are rarely used for calves and never used for cows, were compared with 30 neighboring conventional dairy farms, where antimicrobials were routinely used for animals for all ages. Fecal specimens from 10 cows and 10 calves on 120 farm visits yielded 332 Campylobacter isolates. The prevalence of Campylobacter spp. in organic and conventional farms was 26.7 and 29.1%, and the prevalence was not statistically different between the two types of farms. Campylobacter prevalence was significantly higher in March than in September, higher in calves than in cows, and higher in smaller farms than in large farms. The rates of retained placenta, pneumonia, mastitis, and abortion were associated with the proportion of Campylobacter isolation from fecal samples. The gradient disk diffusion MIC method (Etest) was used for testing susceptibility to four antimicrobial agents: ciprofloxacin, gentamicin, erythromycin, and tetracycline. Two isolates were resistant to ciprofloxacin, and none of isolates was resistant to gentamicin or erythromycin. Resistance to tetracycline was 45% (148 of 332 isolates). Tetracycline resistance was found more frequently in calves than in cows (P = 0.042), but no difference was observed between organic and conventional farms. When we used Campylobacter spp. as indicator bacteria, we saw no evidence that restriction of antimicrobial use on dairy farms was associated with prevalence of resistance to ciprofloxacin, gentamicin, erythromycin, and tetracycline. PMID:15006764

  9. Comparison of prevalence and antimicrobial susceptibilities of Campylobacter spp. isolates from organic and conventional dairy herds in Wisconsin.

    PubMed

    Sato, K; Bartlett, P C; Kaneene, J B; Downes, F P

    2004-03-01

    The prevalence and antimicrobial susceptibilities of Campylobacter spp. isolates from bovine feces were compared between organic and conventional dairy herds. Thirty organic dairy herds, where antimicrobials are rarely used for calves and never used for cows, were compared with 30 neighboring conventional dairy farms, where antimicrobials were routinely used for animals for all ages. Fecal specimens from 10 cows and 10 calves on 120 farm visits yielded 332 Campylobacter isolates. The prevalence of Campylobacter spp. in organic and conventional farms was 26.7 and 29.1%, and the prevalence was not statistically different between the two types of farms. Campylobacter prevalence was significantly higher in March than in September, higher in calves than in cows, and higher in smaller farms than in large farms. The rates of retained placenta, pneumonia, mastitis, and abortion were associated with the proportion of Campylobacter isolation from fecal samples. The gradient disk diffusion MIC method (Etest) was used for testing susceptibility to four antimicrobial agents: ciprofloxacin, gentamicin, erythromycin, and tetracycline. Two isolates were resistant to ciprofloxacin, and none of isolates was resistant to gentamicin or erythromycin. Resistance to tetracycline was 45% (148 of 332 isolates). Tetracycline resistance was found more frequently in calves than in cows (P = 0.042), but no difference was observed between organic and conventional farms. When we used Campylobacter spp. as indicator bacteria, we saw no evidence that restriction of antimicrobial use on dairy farms was associated with prevalence of resistance to ciprofloxacin, gentamicin, erythromycin, and tetracycline.

  10. Antibodies to major pasture borne helminth infections in bulk-tank milk samples from organic and nearby conventional dairy herds in south-central Sweden.

    PubMed

    Höglund, Johan; Dahlström, Frida; Engström, Annie; Hessle, Anna; Jakubek, Eva-Britt; Schnieder, Thomas; Strube, Christina; Sollenberg, Sofia

    2010-08-04

    The objective of this randomised pairwise survey was to compare the regional distribution of antibody levels against the three most important helminth infections in organic and conventional dairy herds in Sweden. Bulk-tank milk from 105 organic farms and 105 neighbouring conventional dairy farms with access to pasture in south-central Sweden were collected in September 2008. Samples were also collected from 8 organic and 8 conventional herds located in a much more restricted area, on the same as well as 3 additional occasions during the grazing season, to reveal evidence for seasonal patterns against cattle stomach worm (Ostertagia ostertagi). Antibody levels to the stomach worm (O. ostertagi), liver fluke (Fasciola hepatica) and lungworm (Dictyocaulus viviparus) were then determined by detection of specific antibodies using three different enzyme-linked immunosorbent assays (ELISAs). According to the Svanovir Ostertagia ELISA, the mean optical density ratio (ODR) was significantly higher in the milk from organic compared to conventional herds, i.e. 0.82 (95% CL=0.78-0.86) versus 0.66 (0.61-0.71). However, no significant differences were observed in the samples collected at different time points from the same 16 herds (F(3,39)=1.18, P=0.32). Antibodies to D. viviparus infection were diagnosed with an ELISA based on recombinant major sperm protein (MSP), and seropositivity was found in 21 (18%) of the 113 organic herds and 11 (9%) of the 113 conventional herds. The seroprevalence of D. viviparus was somewhat higher in the organic herds (Chi-square=3.65, P=0.056), but with the positive conventional herds were located in the vicinity of infected organic herds. Of the 16 herds that were sampled on repeated occasions, as many as 10 (63%), were seropositive on at least one sampling occasion. Many of these turned positive towards the end of the grazing season. Only one herd was positive in all 4 samples and 3 were positive only at turn-out. Considering F. hepatica there

  11. Case study: Differences in milk characteristics between a cow herd transitioning to organic versus milk from a conventional dairy herd

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Differences between organic and conventional milk were studied by comparing two adjacent farms over a 12-mo period starting at the beginning of the grazing season, thus eliminating variables due to geography and weather. Milk was collected from a farm where cows were fed a conventional total mixed ...

  12. Herd-level factors associated with isolation of Salmonella in a multi-state study of conventional and organic dairy farms I. Salmonella shedding in cows.

    PubMed

    Fossler, C P; Wells, S J; Kaneene, J B; Ruegg, P L; Warnick, L D; Bender, J B; Eberly, L E; Godden, S M; Halbert, L W

    2005-09-12

    The objective of this study was to evaluate associations between herd characteristics and the isolation of Salmonella from dairy cows in Minnesota, Wisconsin, Michigan, and New York. Study farms were 129 conventional and organic farms enrolled without regard to previous history of Salmonella infection. Herds were sampled at 2-month intervals over a 1-year period. This is the largest study to date on Salmonella shedding in dairy cows and the only study evaluating herd-level risk factors using longitudinal sampling to characterize Salmonella shedding on dairy farms. Salmonella was isolated in fecal samples from 1026 (4.9%) of 20,089 cows. Over the course of the study, 113 (87.6%) of 129 farms had at least one positive cow sample. Multi-variable logistic regression using the generalized estimating equations approach was used to test the association between herd-level risk factors and the dependent variable of within-herd prevalence by visit (number of Salmonella-positive cows/number of cows sampled) after adjustment for effects of herd size, season, state of origin, and the multiple sampling occasions per herd. Factors retained in the final model included lack of use of tiestall or stanchion facilities to house lactating cows (OR=1.9; 95% CI: 1.1-3.3), not storing all purchased concentrate or protein feeds in an enclosed building (OR=2.5; 95% CI: 1.3-4.9), not using monensin in weaned calf or bred heifer diets (OR=3.2; 95% CI: 2.0-5.4), access of lactating or dry cows to surface water (e.g., lake, pond, river, or stream) (OR=2.3; 95% CI: 1.3-3.9), disposal of manure in liquid form (slurry or irrigation, as opposed to disposal of manure by broadcast/solid spreader only) on owned or rented land (OR=1.8; 95% CI: 1.3-3.9), and cows eating or grazing of roughage from fields where manure was applied in solid or liquid form and not plowed under during the same growing season (OR=1.8; 95% CI: 1.0-3.0). A seasonal association was also present as cows were more likely to be

  13. 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…

  14. Herd-level factors associated with isolation of Salmonella in a multi-state study of conventional and organic dairy farms II. Salmonella shedding in calves.

    PubMed

    Fossler, C P; Wells, S J; Kaneene, J B; Ruegg, P L; Warnick, L D; Bender, J B; Eberly, L E; Godden, S M; Halbert, L W

    2005-09-12

    The objective of this study was to evaluate associations between herd-level factors and the isolation of Salmonella in calves from dairy farms in Minnesota, Wisconsin, Michigan and New York. Study farms were 129 conventional and organic farms enrolled without regard to previous history of Salmonella infection. Herds were sampled at 2-month intervals over a 1-year period. Salmonella was isolated in fecal samples from 176 (3.8%) of 4673 preweaned calves with 40 (31.0%) of 129 farms having at least one positive calf sample over the course of the study. Multivariable logistic regression using the generalized estimating equations approach was used to evaluate risk factors for Salmonella shedding after adjustment for effects of herd size, season, state of origin and the multiple sampling occasions per herd. Factors retained in the final model that were associated with an increased odds for Salmonella shedding were lack of routine feeding of milk replacer containing antimicrobials to preweaned calves (OR=2.8, 95% CI: 1.4, 5.8), use of maternity housing as a hospital area for sick cows more than once a month (OR=2.1, 95% CI: 1.1, 4.0), and cow prevalence level by visit, categorized into the following four-levels: > or =20% (OR=11.6, 95% CI: 5.7, 23.7), 10-19.9% (OR=4.7, 95% CI: 2.0, 11.5), 0.1-9.9% (OR=3.6, 95% CI: 1.5, 8.7) and 0% (reference level). Herd size was not associated with Salmonella shedding in the final multivariable model.

  15. Herd-level risk factors associated with cow mortality in Swedish dairy herds.

    PubMed

    Alvåsen, K; Jansson Mörk, M; Hallén Sandgren, C; Thomsen, P T; Emanuelson, U

    2012-08-01

    An increase in on-farm mortality (euthanasia and death) in dairy herds has been reported in several countries in the last decade. This does not only imply possible problems with animal welfare, but it also causes economic losses to the farmer. The objective of this study was to evaluate time trends in on-farm dairy cow mortality in Sweden and identify potential herd-level risk factors. Data were retrieved on all Swedish dairy herds enrolled in the milk recording scheme between 2002 and 2010. Herds with a herd size of <20 cows or a mortality rate (MR) of >40 dead or euthanized cows per 100 cow-years were excluded. Two different models were used: 1 multiple-year analysis, which included 6,898 herds during the period 2002 to 2010 and 1 single-year analysis including 4,252 herds for the year 2010, where other variables that were not present during the entire multiple year study were analyzed. The outcome variable was the number of euthanized and dead cows per year and season. A negative binomial regression model, adjusted for clustering within herd, was applied to both models. Fixed effects in the multiple-year analysis were breed, calving interval, herd size, milk yield, region, season, pasture period, and year. The fixed effects in the single-year analysis were breed, calving interval, conventional versus organic farming, herd size, housing system, milk yield, region, and season. The results demonstrated that MR gradually increased from 5.1 to 6.6 events per 100 cow-years during the study period. Swedish MR are consequently on par with, or even greater than, MR among dairy herds in other comparable countries. Higher mortality was associated with larger herd size, longer calving intervals, and herds that had Swedish Holstein as the predominant breed. Lower mortality was observed in herds with a higher herd average milk yield, during the fall and winter, and in organically managed herds. There were regional differences in mortality. An interaction between herd size and

  16. 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

  17. Mastitis and related management factors in certified organic dairy herds in Sweden

    PubMed Central

    Hamilton, Cecilia; Emanuelson, Ulf; Forslund, Kristina; Hansson, Ingrid; Ekman, Torkel

    2006-01-01

    Background Mastitis is one of the major threats to animal health, in organic farming as well as conventional. Preliminary studies of organic dairy herds have indicated better udder health in such herds, as compared to conventional herds. The aim of this paper was to further study mastitis and management related factors in certified organic dairy herds. Methods An observational study of 26 certified organic dairy herds in mid-eastern Sweden was conducted during one year. A large-animal practitioner visited the herds three times and clinically examined and sampled cows, and collected information about general health and management routines. Data on milk production and disorders treated by a veterinarian in the 26 herds, as well as in 1102 conventional herds, were retrieved from official records. Multivariable logistic regression was used to assess associations between herd type (organic vs. conventional) and incidence of disorders. Results The organic herds that took part in the study ranged in size from 12 to 64 cows, in milk production from 3772 to 10334 kg per cow and year, and in bulk milk somatic cell counts from 83000 to 280000 cells/ml. The organic herds were found to have a lower incidence of clinical mastitis, teat injuries, and a lower proportion of cows with a high somatic cell count (as indicated by the UDS, Udder Disease Score) compared to conventional herds. The spectrum of udder pathogenic bacteria was similar to that found in other Swedish studies. Treatment of mastitis was found to be similar to what is practised in conventional herds. Homeopathic remedies were not widely used in the treatment of clinical mastitis. The calves in most of these organic herds suckled their dams for only a few days, which were not considered to substantially affect the udder health. The main management factor that was different from conventional herds was the feeding strategy, where organic herds used a larger share of forage. Conclusion Udder health in Swedish organic

  18. 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

  19. Reasons That Cows in Dairy Herd Improvement Programs Exit the Herd

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This new Animal Improvement Programs Laboratory Research Report was initiated to provide the US industry more comprehensive information on a routine basis on why dairy cows leave Dairy Herd Improvement herds. AIPL had previously published some information on culling rate, but the method used did not...

  20. Trends in noncompliance with milk quality standards for Dairy Herd Improvement herds in the United States

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Frequency of herd noncompliance for somatic cell count (SCC) based on current US and European Union (EU) standards as well as for standards proposed by the National Milk Producers Federation (NMPF) was examined for US Dairy Herd Improvement (DHI) herds. For current US standards, regulatory action is...

  1. Consequence of changing standards for somatic cell count on US Dairy Herd Improvement herds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Consequence of noncompliance with European Union (EU) and current US standards for somatic cell count (SCC) as well as SCC standards proposed by the National Milk Producers Federation was examined for US herds. Somatic cell scores (SCS) from 14,854 Dairy Herd Improvement (DHI) herds were analyzed. H...

  2. Somatic cell counts of milk from Dairy Herd Improvement herds during 2010

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Test-day data from all herds enrolled in Dairy Herd Improvement (DHI) somatic cell testing during 2010 were examined to assess the status of national milk quality. Somatic cell score (SCS) is reported to AIPL and was converted to somatic cell count (SCC) for calculating herd and State averages. The ...

  3. Health of cows, calves and young stock on 26 organic dairy herds in Sweden.

    PubMed

    Hamilton, C; Hansson, I; Ekman, T; Emanuelson, U; Forslund, K

    2002-04-20

    The health and housing of the stock on 26 organic dairy herds in four counties in eastern Sweden were studied for one year. The herds ranged in size from 12 to 64 cows, and their milk production from 3772 to 10,334 kg per cow per year. A large-animal practitioner visited the farms three times during the year, and a random sample of a third of the cows in each herd were examined. The calves and young stock and their housing were also studied. The calves were in good condition in all but four herds; their serum immunoglobulins varied from almost none to high levels. The young stock were in good condition and in good housing in 20 herds. No cows with clinical signs of metabolic disorders were found. Body condition scores were adequate or good except in two herds. Acetone was analysed in milk samples from individual cows three to six weeks postpartum, and only sporadic cases with high levels were found. The incidence of diseases treated by a veterinarian was lower in the organic herds than the average for the conventional herds in the local dairy association. The findings at the farm visits supported these data, and it is evident that a good standard of health and welfare can be achieved in organic dairy herds.

  4. Management practices and reported antimicrobial usage on conventional and organic dairy farms.

    PubMed

    Zwald, A G; Ruegg, P L; Kaneene, J B; Warnick, L D; Wells, S J; Fossler, C; Halbert, L W

    2004-01-01

    The primary objective was to compare reported antimicrobial usage between conventional and organic dairy farms. A secondary objective was to contrast selected management characteristics of conventional and organic dairy herds. A questionnaire was administered on site to selected dairy farmers located in Michigan, Minnesota, New York, and Wisconsin. Organic herds (n = 32) were smaller and produced less milk than conventional herds (n = 99). Lactating cows in organic dairies were more likely to be housed in tie stalls, whereas most conventional dairies housed cows in free stalls and milked in a parlor. Total mixed rations and purchased feeds were used on more conventional dairy farms compared with organic dairy farms. Conventional dairy producers were more likely to use advice from veterinarians for recommendations of treatment, and organic dairy producers were more likely to rely on advice from other farmers. Based on recall of antibiotic usage in the previous 60 d, 5.1, 84.9, 9.1, and 0.9% of farmers with conventional herds reported treatment of none, 1 to 10%, 11 to 25%, and >25% of milk cows, respectively. Most organic farmers (90.6%) reported no antibiotic treatments of milk cows, whereas 9.4% reported treating 1 to 10% of milk cows. Ceftiofur was the most commonly reported antibiotic for both farm types. Milk replacer containing antibiotics was reportedly used on 49.5% of conventional herds but only on one organic herd (3.1%). Antibiotics were used in heifer calves on 74.7% of conventional herds versus 21.9% of organic herds. Antibiotics to treat mastitis were used on 79.8% of conventional herds but on none of the organic herds. Most organic farms were in compliance with standards in advance of implementation of regulations.

  5. Subacute ruminal acidosis in Dutch dairy herds.

    PubMed

    Kleen, J L; Hooijer, G A; Rehage, J; Noordhuizen, J P T M

    2009-05-30

    The prevalence of subacute ruminal acidosis (SARA) was determined in 197 dairy cows in 18 herds in the Dutch province of Friesland. Samples of rumen fluid were taken by rumenocentesis from between five and 19 animals on each farm and the pH of each sample was determined. The body condition of 139 of the cows was scored approximately three weeks before they calved and three weeks after they calved. The overall prevalence of SARA was 13.8 per cent, and the prevalence on individual farms ranged between 0 per cent (on seven of the farms) and 38 per cent (on one farm). The stage of lactation did not influence the prevalence of SARA but the cows with the condition lost more body condition over the calving period.

  6. Herd management practices associated with paratuberculosis seroprevalence in Dutch dairy herds.

    PubMed

    Muskens, J; Elbers, A R W; van Weering, H J; Noordhuizen, J P T M

    2003-10-01

    We describe the paratuberculosis management practices applied in dairy herds in the Netherlands. The findings from paratuberculosis seronegative and seropositive herds were compared to discover possible risk factors. In total, 370 randomly selected herds with > or =20 dairy cows were surveyed. A questionnaire was used to collect data on current and previous paratuberculosis management practices. All cattle aged > or =3 years were serologically tested for paratuberculosis using an enzyme-linked immunosorbent assay. Herds with >33 tested cattle, of which only one was seropositive, were excluded to reduce the risk of including false-positive herds in the analysis. A comparison of the management data of the seronegative herds (n = 166) and the seropositive herds (n = 143) showed that in both groups important management measures for the prevention of paratuberculosis, such as calving in a cleaned calving area, removing the calf immediately after birth, and feeding paratuberculosis non-suspect roughage to calves, were used only rarely. However, such measures should be regarded as the critical first step to control the disease and/or reduce its prevalence. Using univariable analysis, four factors were statistically different between seronegative and seropositive herds: herd size, cows with clinical signs of paratuberculosis, prompt selling of clinically diseased cattle and feeding milk replacer. Using a multivariable logistic regression model, only herd size was a significantly different factor. These results indicate that most of the paratuberculosis preventive management measures were executed on these Dutch dairy farms only to a limited extent.

  7. Somatic cell counts of milk from Dairy Herd Improvement herds during 2008

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Test-day data from all herds enrolled in Dairy Herd Improvement (DHI) somatic cell testing during 2008 were examined to assess the status of national milk quality. Cows with records failing some AIPL editing procedures were excluded. Somatic cell score (SCS) is reported to AIPL and was converted to ...

  8. Somatic cell counts of milk from Dairy Herd Improvement herds during 2009

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Test-day data from all herds enrolled in Dairy Herd Improvement (DHI) somatic cell testing during 2009 were examined to assess the status of national milk quality. Cows with records failing some AIPL editing procedures were excluded. Somatic cell score (SCS) is reported to AIPL and was converted to ...

  9. Somatic Cell Counts of Milk from Dairy Herd Improvement Herds during 2007

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Test-day data from all herds enrolled in Dairy Herd Improvement (DHI) somatic cell testing during 2007 were examined to assess the status of national milk quality. Cows with records failing some AIPL editing procedures were excluded. Somatic cell score (SCS) is reported to AIPL and was converted to ...

  10. Management of mastitis on organic and conventional dairy farms.

    PubMed

    Ruegg, P L

    2009-04-01

    This paper compares management of mastitis on organic dairy farms with that on conventional dairy farms. National standards for organic production vary by country. In the United States, usage of antimicrobials to treat dairy cattle results in permanent loss of organic status of the animal, effectively limiting treatment choices for animals experiencing bacterial diseases. There are no products approved by the US Food and Drug Administration that can be used for treatment of mastitis on organic dairy farms, and usage of unapproved products is contrary to Food and Drug Administration guidelines. In general, organic dairy farms tend to be smaller, produce less, and more likely to be housed and milked in traditional barns as compared with conventionally managed herds. It is difficult to compare disease rates between herds managed conventionally or organically because perception and detection of disease is influenced by management system. To date, no studies have been published with the defined objective of comparing animal health on organic dairy herds with that on conventional dairy herds in the United States. European studies have not documented significant differences in animal health based on adoption of organic management. Few differences in bulk tank somatic cell counts have been identified between organic and conventional herds. Farmers that have adopted organic management consistently report fewer cases of clinical mastitis, but organic farmers do not use the same criteria to detect clinical mastitis. European dairy farmers that adopt organic management report use of a variety of conventional and alternative therapies for treatment and control of mastitis. In the United States, organic farmers treat clinical mastitis using a variety of alternative therapies including whey-based products, botanicals, vitamin supplements, and homeopathy. Organic farmers in the United States use a variety of alternative products to treat cows at dry-off. Virtually no data are

  11. Characterizing biosecurity, health, and culling during dairy herd expansions.

    PubMed

    Faust, M A; Kinsel, M L; Kirkpatrick, M A

    2001-04-01

    Our objectives were to investigate strategies for biosecurity, expansion, and culling for expanding dairy herds in the Upper Midwest. Eighteen dairies in Iowa and Wisconsin were visited, and dairy managers and veterinarians were interviewed to characterize five biosecurity practices, herd culling practices, vaccines administered, and ensuing disease status for the herds. The majority of herds that were interviewed failed to employ comprehensive biosecurity programs for incoming cattle. Nearly 60% of herds obtained cattle from sources for which it was difficult to document genetic backgrounds and health histories, fewer than half required health testing for incoming cattle, and approximately 50% quarantined new cattle on arrival. Despite high rates of vaccination for bovine viral diarrhea, all herd owners and managers indicated that herd biosecurity was compromised as a result of expansion. Half of the interviewed herds indicated that bovine viral diarrhea and papillomatous digital dermatitis were notable disease problems. Herds that obtained cattle with unknown backgrounds and health status experienced the largest number of diseases. Before expansion, the most frequently cited reasons for culling were reproductively unsound; low milk production; mastitis, poor udder health, and high SCC; during expansion, the strategic decision to cull cows for low milk production was used less often. In addition, the stochastic simulation model, DairyORACLE, was used to evaluate economic outcomes for several expansion alternatives. Five model scenarios studied were: base scenario (herd size was maintained) and four expansion scenarios--all paired combinations of heifer quality (high, low) and voluntary culling (implemented, not implemented). Culling for low milk production yielded an additional $23.29 annually (6-yr annuity) per cow, but on the basis of purchased replacements, no voluntary culling was most profitable. Purchasing high versus low quality replacement heifers for

  12. 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

  13. Housing system and herd size interactions in Norwegian dairy herds; associations with performance and disease incidence

    PubMed Central

    2010-01-01

    Background According to the Norwegian animal welfare regulations, it has been forbidden to build new tie-stall barns since the end of 2004. Previous studies have shown that cow performance and health differ between housing systems. The interaction between housing system and herd size with respect to performance and disease incidence has not been evaluated. Methods Cow performance and health in 620 herds housed in free-stall barns were compared with in 192 herds housed in tie-stall barns based on a mail survey and data from the Norwegian Dairy Herd Recording and Cattle Health Systems. The housing systems herds were comparable with respect to herd size (15-55 cows). Associations between performance/disease incidence and housing system, herd size and year of building the cow barn were tested in general linear models, and values for fixed herd size of 20 and 50 cows were calculated. On the individual cow level mixed models were run to test the effect of among others housing system and herd size on test-day milk yield, and to evaluate lactation curves in different parities. All cows were of the Norwegian Red Breed. Results Average milk production per cow-year was 134 kg lower in free-stall herd than in tie-stall herds, but in the range 27-45 cows there was no significant difference in yields between the herd categories. In herds with less than 27 cows there were increasingly lower yields in free-stalls, particularly in first parity, whereas the yields were increasingly higher in free-stalls with more than 45 cows. In free-stalls fertility was better, calving interval shorter, and the incidence rate of teat injuries, ketosis, indigestions, anoestrus and cystic ovaries was lower than in tie-stalls. All of these factors were more favourable in estimated 50-cow herds as compared to 20-cow herds. In the larger herd category, bulk milk somatic cell counts were higher, and the incidence rate of mastitis (all cases) and all diseases was lower. Conclusion This study has shown

  14. [Veterinary herd health consultancy on dairy farms: guidelines for starters].

    PubMed

    Kremer, W D; Noordhuizen, J P; Weeda, J T

    2001-07-01

    This paper presents a guideline which can be used when setting up a professional veterinary herd health and production management advisory programme for dairy farms. Earlier research showed that dairy farmers prefer a structured professional programme and ask their veterinary surgeons to provide an optimal veterinary advisory programme for their dairy farms with a clear structure and contents, and well-planned activities. The guideline presented here should aid in providing the farmers with that clarity, structure, and planning. This should ultimately lead to a more professional implementation of veterinary advisory programmes.

  15. Impacts of dairy diagnostic teams on herd performance.

    PubMed

    Weinand, D; Conlin, B J

    2003-05-01

    This study evaluated impacts of educational diagnostic teams of consultants used to transfer technology to dairy farms. Herd management performance changes were measured by comparing Dairy Herd Improvement data from 38 project farms to data from herds that were geographical contemporaries. The value of focused goals for effecting change was also assessed. Interviews provided producers' perception of project outcomes and insight on organization and conduct of dairy diagnostic teams. Changes observed in project herds were small compared with controls with tendencies for increased herd size and improved milk production per cow. Focused goals had greater impacts on increasing herd size, milk per cow, first lactation peak milk, reducing age at first calving, and percentages of cows with subclinical mastitis. Time, money, facility limitations, labor, and alternative priorities were the most cited constraints to implementing changes. Satisfaction scores of producers were significantly related to the degree that team recommendations were followed. Improved attitudes, quality of life, and financial well-being were benefits listed by a majority of producers from participation in the project. If similar projects were to be offered, 83% said they would participate again, and 69% indicated they would pay at least some of the costs. Project farms served as demonstration farms for 1930 other producers in their respective locales, resulting in a multiplier effect of original advice given by consultant teams. Suggestions by farmer participants for improvements in dairy diagnostic teams included needs for at least some unbiased team members, more frequent meetings, more follow-up on recommendations, and consistency of recommendations with family goals.

  16. 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

  17. 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

  18. 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.

  19. Veterinary dairy herd health management in Europe: constraints and perspectives.

    PubMed

    Cannas da Silva, J; Noordhuizen, J P T M; Vagneur, M; Bexiga, R; Gelfert, C C; Baumgartner, W

    2006-03-01

    The nature of veterinary work in dairy health management in Europe has changed over the past years and will change even more dramatically in the near future. The consumers and the media show increasing concern about animal welfare, safety of products of animal origin and traceability of animal products. Farmers in Europe have to produce under strict, often expensive and laborious regulations, while still commercially competing with farmers outside the EU and not subject to the same rules. Veterinarians should adapt their knowledge and skills to the new challenges and developments of the dairy sector. Dairy farmers nowadays ask for support in areas that go beyond clinical activities: environmental protection, welfare, nutrition, grassland management, economics and business management. Bovine practitioners should be able to advise in many different areas and subjects--that is the challenge to our profession. Veterinary education with regards to cattle health management should start with individual animal clinical work, which constitutes the basis of herd health advisory programmes. The bovine practitioner should then look beyond that and regard the herd as the unit. Each diseased cow or group of cows should be detected early enough to avoid financial losses or such losses should be prevented altogether by detecting and managing risk factors contributing to disease occurrence. Herd health and production management programmes represent the first level to optimise dairy farm performance. Expansions to that should further be considered, comprising both animal health and welfare issues, as well as food safety and public health issues. The latter could be addressed by quality risk management programmes following the HACCP-principles. Cattle veterinarians should follow recent developments and invest in new skills and knowledge in order to maintain their usefulness to the modern dairy farmer. Finally we are convinced that the cattle practitioner should evolve into this

  20. Aetiology of clinical mastitis in six Somerset dairy herds.

    PubMed

    Bradley, A J; Green, M J

    2001-06-02

    Clinical mastitis was monitored in six Somerset dairy herds for one year. The herds all had three-month geometric mean bulk milk somatic cell counts of less than 250,000 cells/ml. Escherichia coli was the predominant pathogen isolated on all the farms and in all months of the year. Environmental pathogens accounted for 61.4 per cent of all cases of clinical mastitis and for 79.3 per cent of the mastitis cases in which an aetiological agent was identified. The mean annual incidence was 41.6 cases per 100 cows (range 14 to 75). Affected cows suffered a mean of 1.5 cases and 16.4 per cent of quarters suffered at least one repeat case. Mastitis due to E. coli was more severe than mastitis due to other causes and it tended to be more severe in early lactation and during the housing period. Mastitis was significantly more severe (grades 2 and 3) in the herd with the lowest bulk milk somatic cell count and in the herd which was kept indoors throughout the year than in the other four herds. Mastitis was fatal in 2.2 per cent of cases and resulted in the death of 0.6 per cent of the lactating cows.

  1. Antimicrobial susceptibility of Salmonella from organic and conventional dairy farms.

    PubMed

    Ray, K A; Warnick, L D; Mitchell, R M; Kaneene, J B; Ruegg, P L; Wells, S J; Fossler, C P; Halbert, L W; May, K

    2006-06-01

    The objective of this study was to compare antimicrobial susceptibility of Salmonella isolated from conventional and organic dairy farms in the Midwest and Northeast United States. Environmental and fecal samples were collected from organic (n = 26) and conventional (n = 69) farms in Michigan, Minnesota, New York, and Wisconsin every 2 mo from August 2000 to October 2001. Salmonella isolates (n = 1,243) were tested using a broth microdilution method for susceptibility to amoxicillin-clavulanic acid, ampicillin, ceftiofur, ceftriaxone, cephalothin, chloramphenicol, ciprofloxacin, gentamicin, kanamycin, nalidixic acid, streptomycin, sulfamethoxazole, tetracycline, and trimethoprim-sulfamethoxazole. Herd-level logistic regression and logistic proportional hazards multivariable models were used to examine the association between farm management type and susceptibility to antimicrobial agents. For most antimicrobial agents tested, susceptibility of Salmonella isolates was similar on organic and conventional herds when controlling for herd size and state. Conventional farms were more likely to have at least one Salmonella isolate resistant to streptomycin using logistic regression (odds ratio = 7.5; 95% confidence interval = 1.7-5.4). Conventional farms were more likely to have Salmonella isolates with greater resistance to streptomycin (odds ratio = 5.4; 95% confidence interval = 1.5-19.0) and sulfamethoxazole (odds ratio = 4.2; 95% confidence interval = 1.2-14.1) using logistic proportional hazards models. Although not statistically significant, conventional farms tended to be more likely to have at least one Salmonella isolate resistant to 5 or more antimicrobial agents when compared with organic farms.

  2. Characteristics of the USA dairy herd as related to management and demographic elements

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The data characteristics of the United States dairy herd related to animals enrolled in milk recording (dairy herd improvement) are the basic foundation and important influencers for the management and genetic progress achieved in a population or animal production unit. The amount, characteristics ...

  3. Synchronization and Artificial Insemination Strategies in Dairy Herds.

    PubMed

    Stevenson, Jeffrey S

    2016-07-01

    Timed artificial insemination (AI) programs are commonly used in the dairy industry for lactating cows, but less so in replacement heifers. Excellent programs using combinations of prostaglandin F2α and gonadotropin-releasing hormone in protocols relying on timed AI without detection of estrus or in protocols that combine timed AI with inseminations performed after detected estrus are able to achieve acceptable pregnancy percentages. In herds with excellent estrus detection, timed AI programs serve as a failsafe system to address cows or heifers not yet inseminated after a defined period of estrus detection.

  4. A Survey of Mastitis in Selected Ontario Dairy Herds

    PubMed Central

    Brooks, B. W.; Barnum, D. A.; Meek, A. H.

    1982-01-01

    A mastitis survey involving 74 Ontario dairy herds was conducted. The prevalence of infection at the quarter level was found to be 4.1% with Streptococcus agalactiae, 4.5% with other streptococcal species and 8.0% with Staphylococcus aureus. Regardless of the infection status, the geometric mean somatic cell count was found to increase with age of the cow but no increase was observed with increasing stage of lactation. The percentage of cows from which a bacterial pathogen was isolated increased with age but not with stage of lactation. PMID:17422140

  5. Developments in veterinary herd health programmes on dairy farms: a review.

    PubMed

    Noordhuizen, J P; Wentink, G H

    2001-11-01

    This review article addresses some major developments in herd health programmes for dairy farms over the last decades. It focuses particularly on herd health and production management programmes that use protocols and monitoring activities. The article further emphasizes the need for merging herd health programmes with quantitative epidemiological principles and methods. Subsequently, this article points to the latest developments regarding quality assurance in the dairy sector and some quality management methods. Quality should be regarded in its broadest sense. The importance of integrating veterinary herd health programmes and quality (risk) management support at a dairy farm level is stressed. Examples are provided.

  6. Comparisons of milk quality on North Carolina organic and conventional dairies.

    PubMed

    Mullen, K A E; Sparks, L G; Lyman, R L; Washburn, S P; Anderson, K L

    2013-10-01

    The organic dairy industry is growing rapidly across the United States and has recently expanded into the southeastern states. To date, no published comparisons of milk quality exist between organic and conventional dairies in the Southeastern United States. Maintaining high milk quality is challenging in this region due to the longer periods of high heat and humidity. The objective of this observational study was to compare milk quality on organic and conventional dairies in North Carolina during the warm summer months of the year. Data were compared from 7 organically and 7 conventionally managed herds in North Carolina. To assess milk quality, milk samples were aseptically collected from each functional quarter of each cow in the milking herds at the time of sampling and linear somatic cell scores (SCS) were obtained for individual cows. A total of 4,793 quarter milk samples (2,526 conventional and 2,267 organic) were collected from 1,247 cows (652 conventional and 595 organic). Milk samples were cultured and bacterial growth was identified using protocols consistent with those of the National Mastitis Council (Verona, WI). Subclinical mastitis was defined as the presence of SCS ≥ 4 and also a microbiological infection in at least 1 quarter. The proportion of cows with subclinical mastitis did not differ between conventional (20.8%) and organic (23.3%) herds. No significant difference was observed between herd management types in the proportion of cows without microbiological growth in milk samples. Also, no significant differences were observed between organic and conventional herds for cow-level prevalence of Staphylococcus aureus, coagulase-negative Staphylococcus spp., Streptococcus spp., or Corynebacterium spp. Two of the organic herds had a notably higher prevalence of Corynebacterium spp. and higher SCS. Coliforms were found in 5 of 7 conventional herds and in only 1 of 7 organic herds. Mean SCS did not differ between conventional (3.3±0.2) and organic

  7. The Canadian National Dairy Study 2015-Adoption of milking practices in Canadian dairy herds.

    PubMed

    Belage, E; Dufour, S; Bauman, C; Jones-Bitton, A; Kelton, D F

    2017-03-16

    Several studies have investigated which management practices have the greatest effect on udder health, but little information is available on how broadly the recommended milking practices are adopted across Canada. The National Dairy Study 2015 was designed to gather dairy cattle health and management data on dairy farms across Canada. The objectives of the present study were to describe the current proportions of adoption of milking practices on Canadian dairy farms, and identify factors associated with their use on farms. A bilingual questionnaire measuring use of various practices, including an udder health-specific section, was developed and sent to all Canadian dairy farms. The questions in the udder health section of the questionnaire were adapted from a bilingual questionnaire previously validated and containing questions regarding general milking hygiene and routine, and on-farm mastitis management. Chi-squared tests were used to investigate simple associations between adoption of practices and various explanatory variables including region, milking system, herd size, and bulk tank somatic cell count. In total, 1,373 dairy producers completed the survey. The regional distribution of the participants was representative of the Canadian dairy farm population, and milk quality was, on average, similar to nonparticipants. Overall, Canadian dairy producers followed the recommendations for milking procedures, but some were more extensively used than others. Fore-stripping, cleaning teats, wiping teats dry, using single-cow towels, and use of postmilking teat disinfectant were widely adopted. Use of gloves and glove hygiene, use of a premilking teat disinfectant, and use of automatic takeoffs were not as extensively implemented. Adoption percentages for several practices, including use of gloves, use of a premilking teat disinfectant, teat drying methods, and use of automatic takeoffs were significantly associated with milking system, herd size, and region. It

  8. Prevalence and risk factors for extended-spectrum β-lactamase or AmpC-producing Escherichia coli in organic dairy herds in the Netherlands.

    PubMed

    Santman-Berends, I M G A; Gonggrijp, M A; Hage, J J; Heuvelink, A E; Velthuis, A; Lam, T J G M; van Schaik, G

    2017-01-01

    herds was 0.5, which was not significantly different between ESBL/AmpC-positive and unsuspected dairy herds. No association could be found between the use of different types of antimicrobials, such as third- and fourth-generation cephalosporins, and ESBL/AmpC herd status. Factors that were associated with higher odds of being ESBL/AmpC-positive were pig farms located within a 2-km radius of the barn, applying parental treatment for clinical mastitis, and providing milk replacer to the female calves after colostrum intake. The prevalence of ESBL/AmpC in organic dairy herds appeared lower than the prevalence in previous studies conducted in conventional dairy herds. Apparently, ESBL/AmpC are also present in herds with low AMU; this indicates that other factors than AMU are also associated with ESBL/AmpC herd status.

  9. 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.

  10. Methods for assessing phosphorus overfeeding on organic and conventional dairy farms.

    PubMed

    Nordqvist, M; Holtenius, K; Spörndly, R

    2014-02-01

    Phosphorus (P) losses from dairy farms can severely damage aquatic ecosystems, so it is important to have tools to assess overfeeding of P. This study screened P intake and faecal excretion of different P fractions in dairy cows on conventional and organic farms, compared the P feeding level of the herds against the recommendations and analysed different sampling and analysis methods for assessing the general status of P feeding on the farms. The organic (n=14) and conventional farms (n=15) were of comparable size and were located in southern Sweden. On each farm, feed intake was registered for 10 cows representing four different lactation stages and their P intake was calculated and related to current recommendations. Faecal samples taken from the same cows were analysed for total P (TP) and soluble P. Milk production data for the cows were obtained from the Swedish official milk recording scheme. TP was determined in one slurry sample per farm. More than 70% of the cows studied, representing both conventional and organic herds, consumed P in excess of the recommendations. Conventional herds had higher P content in the ration than organic herds, and lactating cows in conventional herds had higher faecal concentrations of total and soluble P than those in organic herds. However in dry cows, the P content of the ration and soluble P and TP in faeces did not differ between the two management systems. Soluble P was well correlated to TP in faeces, and both were good indicators of P overfeeding.

  11. Introduction of new multidrug-resistant Salmonella enterica strains into commercial dairy herds.

    PubMed

    Adhikari, B; Besser, T E; Gay, J M; Fox, L K; Davis, M A; Cobbold, R N; Berge, A C; McClanahan, R; Hancock, D D

    2009-09-01

    A longitudinal observational study of 59 dairy herds was conducted in Washington State to estimate the rate of introduction of new multidrug-resistant (MDR) Salmonella enterica strains onto commercial dairy herds. Samples were collected on these herds over 7 visits separated by intervals of 2 to 4 mo over a period of 15 to 21 mo. Samples were cultured for Salmonella spp. and serogroup, serovar, and antimicrobial susceptibility patterns were identified for MDR Salmonella isolates. Fingerprinting generated by pulsed-field gel electrophoresis (PFGE) using XbaI restriction enzyme digestion generated genotyping profiles for all MDR isolates identified in the study. The rate of new MDR Salmonella strain introduction was 0.9 per herd-year (95% confidence interval: 0.6-1.4). The rates for the most commonly introduced MDR Salmonella serovars were 0.4/herd-year for Typhimurium, 1.2/herd-year for Newport, and 0.1/herd-year for Dublin. Thirty-three of 59 herds (56%) had at least one new MDR Salmonella introduction during the study period. The number of new MDR Salmonella strains acquired by dairy herds ranged from zero to 8. Thirteen of the 59 herds had a history of clinical salmonellosis. Among these 13 herds, 6 herds acquired new MDR Salmonella strains, although these strains were different than historical clinical strains. These data indicate that acquisition of new MDR Salmonella strains by dairy herds was a common event in participating herds, although the number of strains introduced varied greatly among herds.

  12. 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

  13. A comparative study of production performance and animal health practices in organic and conventional dairy systems.

    PubMed

    Silva, Jenevaldo B; Fagundes, Gisele M; Soares, João P G; Fonseca, Adivaldo H; Muir, James P

    2014-10-01

    Health and production management strategies influence environmental impacts of dairies. The objective of this paper was to measure risk factors on health and production parameters on six organic and conventional bovine, caprine, and ovine dairy herds in southeastern Brazil over six consecutive years (2006-2011). The organic operations had lower milk production per animal (P ≤ 0.05), lower calf mortality (P ≤ 0.05), less incidence of mastitis (P ≤ 0.05), fewer rates of spontaneous abortions (P ≤ 0.05), and reduced ectoparasite loads (P ≤ 0.05) compared to conventional herds and flocks. Organic herds, however, had greater prevalence of internal parasitism (P ≤ 0.05) than conventional herds. In all management systems, calves, kids, and lambs had greater oocyte counts than adults. However, calves in the organic group showed lower prevalence of coccidiosis. In addition, animals in the organic system exhibited lower parasitic resistance to anthelmintics. Herd genetic potential, nutritive value of forage, feed intake, and pasture parasite loads, however, may have influenced productive and health parameters. Thus, although conventional herds showed greater milk production and less disease prevalence, future research might quantify the potential implications of these unreported factors.

  14. 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

  15. Hypomagnesemia among cows in a confinement-housed dairy herd.

    PubMed

    Donovan, G Arthur; Steenholdt, Christian; McGehee, Kerry; Lundquist, Rick

    2004-01-01

    Between January and March 2002, 55 cows in a 1,200-cow commercial dairy herd in south Florida died. Most of the cows that were found dead did not have any clinical signs of disease prior to death. Because of a history of a feed change, a bloom of blue-green algae in cow cooling ponds, and initial necropsy findings of moderate enteritis, the preliminary differential diagnosis included clostridial enteritis, blue-green algae toxicosis, and mycotoxicosis. Rumen acidosis, hypomagnesemia, and heavy metal toxicosis were included as secondary considerations. On the basis of physical examination and gross necropsy findings, results of clinicopathol ogic testing, and results of feed and water analyses, a diagnosis of hypomagnesemia was made. Control procedures that were implemented included changing the forage source and increasing the magnesium concentration in the diet.

  16. Postpartum uterine disease and dairy herd reproductive performance: a review.

    PubMed

    LeBlanc, Stephen J

    2008-04-01

    This paper reviews the causes, impact, treatment, and prevention of retained placenta (RP), metritis, and endometritis in dairy cows. The occurrence of each of these diseases largely depends on immune function in the transition period. Retained placenta affects 5-10% of calvings and greatly increases the risk of metritis and endometritis. More field studies are needed to validate criteria for treatment of metritis, but cows with at least two of RP, fever, dullness, and fetid uterine discharge appear to merit treatment with systemic antibiotics. Clinical endometritis affects 15-20% of cows at 4-6 weeks postpartum; an additional 30-35% have subclinical endometritis between 4 and 9 weeks postpartum. Under specific conditions, treatment of cows with endometritis improved pregnancy rate. Systematic use of prostaglandin F(2alpha) at 5 and 7 weeks postpartum may improve pregnancy rate. The economic benefit of efforts to identify and treat endometritis is herd-specific.

  17. Spread of Staphylococcus aureus resistant to penicillin and tetracycline within and between dairy herds.

    PubMed Central

    Waage, S.; Bjorland, J.; Caugant, D. A.; Oppegaard, H.; Tollersrud, T.; Mørk, T.; Aarestrup, F. M.

    2002-01-01

    One hundred and seven bovine isolates of penicillin and tetracycline resistant Staphylococcus aureus, recovered from 25 different dairy herds in various parts of Norway, were characterized using antimicrobial susceptibility testing, multilocus enzyme electrophoresis, ribotyping, plasmid analysis and serotyping of capsular polysaccharide. Forty-one isolates from one particular herd, 37 isolates from 5 herds that used a common pasture and milking parlour in summer and 21 isolates from 12 herds in 8 different counties belonged to the same strain. The remaining 8 isolates, which originated from herds in 5 different counties, were assigned to 6 different strains. Seven out of these 8 isolates had the same plasmid restriction profile. In conclusion, penicillin and tetracycline resistant S. aureus occurring in dairy herds in Norway mainly seems to represent one particular strain that has achieved widespread distribution or belong to one of several different strains carrying identical plasmids. PMID:12211588

  18. 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

  19. Monitoring reproductive performance of small dairy herds in veterinary practice

    PubMed Central

    Lemire, Georges E.; Stalheim, P. Scott; Lemire, Michel R.; Verdon, Lucie; Tiemann, Martin; Bruning, Thomas R.

    1991-01-01

    A descriptive field study involving 87 herds (3608 cows) in two veterinary practices was conducted to compute mean values for a panel of reproductive herd parameters. A method of monitoring herds and identifying those herds experiencing reproductive inefficiency is reported. When comparing the means of herd indices for both practices, only the means for the index “percent in heat by 60 days” were significantly different. Overall, 20 herds were found to have at least one herd index which was significantly different from the mean for all herds. Fourteen herds were found to have significant reproductive inefficiency. If the index “percent problem cows” had not been used, 29% of the herds with reproductive inefficiency would not have been indentified. Our study suggests that it is useful to compare reproductive indices among herds, practices, and regions using a veterinary office microcomputer. PMID:17423859

  20. 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) ...

  1. Environmental sampling to predict fecal prevalence of Salmonella in an intensively monitored dairy herd

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Although dairy cattle are known reservoirs for salmonellae, cattle that are shedding this organism are often asymptomatic and difficult to identify. A dairy herd that was experiencing an outbreak of Salmonella enterica subsp. enterica Cerro was monitored for two years. Fecal samples from the lacta...

  2. 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...

  3. Evaluating the reproductive performance of British beef and dairy herds using national cattle movement records.

    PubMed

    Gates, M C

    2013-11-23

    National cattle movement databases provide a valuable opportunity to monitor the reproductive performance of breeding cattle on an industry-wide scale. In this analysis, records from the Cattle Tracing System database were used to derive key measures of reproductive efficiency for British beef and dairy herds, including calving spread, age at first calving, calving interval, culling rate and calf mortality rate. At the animal level, only 8.5 per cent of beef heifers and 6.9 per cent of dairy heifers calved by the target age of 24 months. The average calving interval was 394 days for beef dams (median: 371) and 426 days for dairy dams (median: 400). Differences in performance were noted between cattle breeds. An estimated 43.9 per cent calves born in dairy herds were crossbreed beef animals, which may limit the availability of replacement dairy heifers. At the herd level, calving spread and calf mortality rates increased with herd size, while average age at first calving, calving interval, and crossbreeding generally decreased with herd size. Dam age, calving month, breed and twinning were significant risk factors for culling and calf mortality at the animal level. Wide variation in performance between individual herds highlights the potential for improving the efficiency of British cattle production.

  4. 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.

  5. Perceptions and risk factors for lameness on organic and small conventional dairy farms.

    PubMed

    Richert, R M; Cicconi, K M; Gamroth, M J; Schukken, Y H; Stiglbauer, K E; Ruegg, P L

    2013-08-01

    Lameness is an important multifactorial disease that affects dairy cattle on both organic (ORG) and conventional (CON) farms. The objective of this study was to characterize perception of lameness and identify risk factors for lameness prevalence on ORG and similarly-sized CON farms. Dairy herds (n=292) were enrolled across 3 states (NY, OR, WI), with CON herds enrolled based on similar herd size and location of ORG herds. During a single herd visit, information was collected about management practices and lameness events occurring in the previous 60 d, and paperwork was left to record lameness events during the 60 d after the visit. During the herd visit, study personnel scored cows for body condition, lameness, and hock condition. For analysis, CON herds were further divided into CON grazing and CON nongrazing. A Poisson regression model was used to assess risk factors for prevalence of cows scored lame. On these relatively small, lower producing farms, the prevalence of lameness in cows scored by study personnel was less than previously reported for larger, higher producing dairy herds located in the United States. Prevalence of lameness was weakly and positively correlated with the rate of lameness calculated using farmer records. Researchers observed lame cows on some farms where farmers perceived that lameness never occurred. An increased prevalence of cows scored lame by study personnel was associated with an increased prevalence of hock lesions, use of CON nongrazing management, and routine use of a footbath. Multiple strategies may be used to manage lameness on farms, including increasing farmer perception of lameness and reduction in exposure of cows to risk factors that contribute to development of lameness.

  6. 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

  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. Relative contributions of neighbourhood and animal movements to Coxiella burnetii infection in dairy cattle herds.

    PubMed

    Nusinovici, Simon; Hoch, Thierry; Widgren, Stefan; Joly, Alain; Lindberg, Ann; Beaudeau, François

    2014-05-01

    Q fever in dairy cattle herds occurs mainly after inhalation of contaminated aerosols generated from excreta by shedder animals. Propagation of Coxiella burnetii, the cause of the disease between ruminant herds could result from transmission between neighbouring herds and/or the introduction of infected shedder animals in healthy herds. The objective of this study were (i) to describe the spatial distribution C. burnetii-infected dairy cattle herds in two different regions: the Finistère District in France (2,829 herds) and the island of Gotland in Sweden (119 herds) and (ii) to quantify and compare the relative contributions of C. burnetii transmission related to neighbourhood and to animal movements on the risk for a herd to be infected. An enzyme--linked immunosorbent assay was used for testing bulk tank milk in May 2012 and June 2011, respectively. Only one geographical cluster of positive herds was identified in north-western Finistère. Logistic regression was used to assess the association of risk for a herd to test positively with local cattle density (the total number of cattle located in a 5 km radius circle) and the in-degree (ID) parameter, a measure of the number of herds from which each herd had received animals directly within the last 2 years. The risk for a herd to test positively was higher for herds with a higher local cattle density [odds ratio (OR) = 2.3, 95% confidence interval (CI) = 1.6-3.2, for herds with a local density between 100 and 120 compared to herds with a local density 60]. The risk was also higher for herds with higher IDs (OR = 2.3, 95% CI = 1.6-3.2, for herds with ID 3 compared to herds that did not introduce animals). The proportion of cases attributable to infections in the neighbourhood in high-density areas was twice the proportion attributable to animal movements, suggesting that wind plays a main role in the transmission.

  9. An assessment of dairy herd bulls in southern Australia: 1. Management practices and bull breeding soundness evaluations.

    PubMed

    Hancock, A S; Younis, P J; Beggs, D S; Mansell, P D; Stevenson, M A; Pyman, M F

    2016-12-01

    In the pasture-based, seasonally calving dairy herds of southern Australia, the mating period usually consists of an initial artificial insemination period followed by a period of natural service using herd bulls. Bull breeding soundness evaluations (BBSE) were performed on 256 bulls from 32 dairy herds in southwest Victoria, using guidelines produced by the Australian Cattle Veterinarians, before and immediately after a single natural mating period. At the same time, herd managers were questioned regarding the management of the bulls. The objectives of this study were to describe the management practices of dairy herd bulls; to describe the causes of increased risk of reduced fertility in dairy herd bulls, as measured by a standard BBSE; and to describe the reasons for bull removal by herd managers during mating. At the premating BBSE, 19.5% of bulls were classified as high risk of reduced fertility, mostly due to physical abnormalities and reduced semen quality. At the postmating BBSE, 36.5% of bulls were classified as high risk of reduced fertility, mostly due to physical abnormalities, primarily lameness. Of the bulls used, 15.9% were removed from normal mating use by the herd manager, predominantly due to lameness and injuries. A premating BBSE is recommended in dairy herd bulls to identify bulls at risk of reduced fertility. Lameness is the most common problem in dairy herd bulls during the natural mating period, and risk factors associated with lameness in these bulls should be identified to better manage herd bulls.

  10. Eradication of bovine leukemia virus infection in commercial dairy herds using the agar gel immunodiffusion test.

    PubMed Central

    Shettigara, P T; Samagh, B S; Lobinowich, E M

    1986-01-01

    Demands for bovine leukemia virus test negative breeding cattle and for semen from bovine leukemia virus test negative bulls by several countries have encouraged the eradication of bovine leukemia virus infection from selected herds in Canada. This project was undertaken to evaluate the suitability of the agar gel immunodiffusion test, standardized to detect anti-bovine leukemia virus glycoprotein antibodies, for eradication of bovine leukemia virus from commercial dairy herds. Of nine participating herds, the prevalence rate of bovine leukemia virus infection was low (less than 10%) in three, medium (11-30%) in four and high (greater than 30%) in two. The herds were tested by the agar gel immunodiffusion test, reactors were removed and the herds were then retested at regular intervals. The results indicate that it is possible to eliminate bovine leukemia virus infection from the herds after two to three cycles of agar gel immunodiffusion tests and prompt removal of the reactors. PMID:3019498

  11. 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

  12. Cow- and herd-level risk factors for on-farm mortality in Midwest US dairy herds.

    PubMed

    Shahid, M Q; Reneau, J K; Chester-Jones, H; Chebel, R C; Endres, M I

    2015-07-01

    The objectives of this study were to describe on-farm mortality and to investigate cow- and herd-level risk factors associated with on-farm mortality in Midwest US dairy herds using lactation survival analysis. We analyzed a total of approximately 5.9 million DHIA lactation records from 10 Midwest US states from January 2006 to December 2010. The cow-level independent variables used in the models were first test-day milk yield, milk fat percent, milk protein percent, fat-to-protein ratio, milk urea nitrogen, somatic cell score, previous dry period, previous calving interval, stillbirth, calf sex, twinning, calving difficulty, season of calving, parity, and breed. The herd-level variables included herd size, calving interval, somatic cell score, 305-d mature-equivalent milk yield, and herd stillbirth percentage. Descriptive analysis showed that overall cow-level mortality rate was 6.4 per 100 cow-years and it increased from 5.9 in 2006 to 6.8 in 2010. Mortality was the primary reason of leaving the herd (19.4% of total culls) followed by reproduction (14.6%), injuries and other (14.0%), low production (12.3%), and mastitis (10.5%). Risk factor analysis showed that increased hazard for mortality was associated with higher fat-to-protein ratio (>1.6 vs. 1 to 1.6), higher milk fat percent, lower milk protein percent, cows with male calves, cows carrying multiple calves, higher milk urea nitrogen, increasing parity, longer previous calving interval, higher first test-day somatic cell score, increased calving difficulty score, and breed (Holstein vs. others). Decreased hazard for mortality was associated with higher first test-day milk yield, higher milk protein, and shorter dry period. For herd-level factors, increased hazard for mortality was associated with increased herd size, increased percentage of stillbirths, higher somatic cell score, and increased herd calving interval. Cows in herds with higher milk yield had lower mortality hazard. Results of the study

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

    PubMed Central

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

    2016-01-01

    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

  14. 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.

  15. A longitudinal study on transmission of Staphylococcus aureus genotype B in Swiss communal dairy herds.

    PubMed

    van den Borne, Bart H P; Graber, Hans U; Voelk, Verena; Sartori, Carlotta; Steiner, Adrian; Haerdi-Landerer, M Christina; Bodmer, Michèle

    2017-01-01

    Staphylococcus aureus is a common mastitis causing pathogen of dairy cattle. Several S. aureus genotypes exist, of which genotype B (GTB) is highly prevalent in Swiss dairy herds. Dairy farming in mountainous regions of Switzerland is characterised by the movement of dairy cattle to communal pasture-based operations at higher altitudes. Cows from different herds of origin share pastures and milking equipment for a period of 2 to 3 months during summer. The aim of this longitudinal observational study was to quantify transmission of S. aureus GTB in communal dairy operations. Cows (n=551) belonging to 7 communal operations were sampled at the beginning and end of the communal period. Transmission parameter β was estimated using a Susceptible-Infectious-Susceptible (SIS) model. The basic reproduction ratio R0 was subsequently derived using previously published information about the duration of infection. Mean transmission parameter β was estimated to be 0.0232 (95% CI: 0.0197-0.0274). R0 was 2.6 (95% CI: 2.2-3.0), indicating that S. aureus GTB is capable of causing major outbreaks in Swiss communal dairy operations. This study emphasized the contagious behaviour of S. aureus GTB. Mastitis management in communal dairy operations should be optimized to reduce S. aureus GTB transmission between cows and back to their herds of origin.

  16. Can pre-collected register data be used to identify dairy herds with good cattle welfare?

    PubMed Central

    2011-01-01

    Abstract Background Pre-recorded register data from dairy herds are available in almost all Nordic countries. These databases can be used for research purposes, and one of the research areas is animal welfare. The aim of this study was to investigate if pre-recorded register data could be used to identify herds with good welfare, and to investigate if a combination of register data sets could be used to be able to more correctly distinguish between herds with good welfare and herds with welfare deficiencies. Methods As a first step, nine animal-based measurements on calves, young stock and cows in 55 randomly selected herds were performed on-farm as the basis for a classification of welfare at the herd level. The definition for being a case herd with “good welfare” was no score lying among the 10% worst in any of the nine welfare measurements. Twenty-eight of the 55 herds were cases according to this definition. As a second step, 65 potential welfare indicators, based on register data in a national dairy database, were identified by expert opinion. In the final step, the extent to which the suggested welfare indicators predicted farms’ as having good welfare according to the stated definition was assessed. Moreover, the effect of combining in sequence a previously developed model that identified herds with poor welfare with the present model identifying herds with good welfare was investigated. Results The final set of welfare indicators used to identify herds with good animal welfare included two fertility measures, cow mortality, stillbirth rate, mastitis incidence and incidence of feed-related diseases (including gastrointestinal disturbances but excluding paralyses and cramps). This set had a test sensitivity of correctly classifying herds with no score lying among the 10% worst of the nine welfare measurements of 96 %. However, the specificity of the test was only 56% indicating difficulties for the test to correctly classifying herds with one or more

  17. 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.

  18. 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

  19. Detection of Mycobacterium bovis-infected dairy herds using PCR in bulk tank milk samples.

    PubMed

    Zumárraga, Martín José; Soutullo, Adriana; García, María Inés; Marini, Rocío; Abdala, Alejandro; Tarabla, Héctor; Echaide, Susana; López, Marcela; Zervini, Elsa; Canal, Ana; Cataldi, Angel Adrián

    2012-02-01

    Bovine tuberculosis (bTB) is a chronic and zoonotic disease due to Mycobacterium bovis. The tuberculosis eradication campaign carried out in Argentina has considerably improved the health situation of the herds. Here we evaluated a strategy to detect M. bovis-infected herds by Touch-Down IS6110 polymerase chain reaction (PCR) in bulk tank raw milk from dairy farms. We evaluated 177 samples from herds with the official tuberculosis free certificate (TFC) and 80 from herds without the certificate, non-tuberculosis-free certificate (NTFC), from 10 departments of Santa Fe province, Argentina. To avoid the effect of Taq polymerase inhibitors, a dilution of DNA template was performed. Positive PCR results were obtained in 102 (40%) of the samples, whereas negative ones were obtained in 155 (60%) of the samples. Importantly, 44% of NTFC and 38% of TFC samples were positive. All samples were subjected to culture in Löwenstein Jensen and Stonebrink media with no positive isolation. The negative predictive value (NPV) of PCR in the TFC group was 95%, while the positive predictive value (PPV) of PCR in the NTFC group was 51%. Based on these results, this work proposes a method that should be applied regularly to detect M. bovis--infected dairy herds, complementary to the official test of tuberculin, or purifed protein derivative (PPD), to control dairy herds, especially those free of tuberculosis.

  20. Manageable risk factors associated with bacterial and coliform counts in unpasteurized bulk milk in Flemish dairy herds.

    PubMed

    Piepers, S; Zrimšek, P; Passchyn, P; De Vliegher, S

    2014-01-01

    Associations between herd management practices and both bacterial counts (BC) and coliform counts (CC) from 254 and 242 dairy herds in Flanders (Belgium), respectively, were studied. Data were analyzed using multivariable, multilevel linear regression analysis, allowing variance components analyses. Both BC and CC fluctuated throughout the year, although the milk quality parameters followed an opposite pattern. Bacterial count values decreased with each increase of the cleaning frequency of the cubicles (once per week, once per day, twice per day, or more than twice per day) between January and March. Herds with a conventional milking parlor had substantially lower BC than herds where the cows were milked using an automatic milking system. Lower BC were observed when the milking parlor was equipped with an automatic cluster removal system, when premilking teat disinfection was applied, when the dry cows were supplemented with a mix of minerals and vitamins, and when the teats were prepared either first wet and dried or via an automatic milking system. Milking cows with a high-pipeline milking parlor setup or with an automatic milking system was associated with substantially higher CC values. Herds where prepartum heifers were often treated with antimicrobials before calving had a lower CC than farms where heifers were either not or only rarely treated. Most variation in BC and CC resided at the herd level rather than at the observation level, indicating that management is important in the control of both BC and CC. Still, only a small proportion of the total variance was explained by factors capturing information related to the milking, herd health, and dry cow management, which suggests that the bacteriological milk quality and, in particular, CC is primarily driven by other factors than the ones included in this study.

  1. [Using on-farm records to evaluate the reproductive performance in dairy herds].

    PubMed

    Iwersen, M; Klein, D; Drillich, M

    2012-01-01

    The designated abolition of the European milk quota system on April 1st 2015 is expected to have tremendous effects on the business environment on most dairy farms. Meanwhile farmers should use weak-point analyses to identify "bottlenecks" within their production and herd management system. As experts in herd health and herd performance, veterinarians should give advice to their clients based on sound analyses of production data. Therefore, accurate and reliable on-farm records are needed. This paper will focus on data management, especially data collection, and will address the concepts of evaluation of reproduction records.

  2. A case-control study of Nocardia mastitis in Nova Scotia dairy herds

    PubMed Central

    Ferns, Lyn; Dohoo, Ian; Donald, Alan

    1991-01-01

    A case-control study was conducted to identify herd production, housing, and hygienic and therapeutic factors associated with a diagnosis of Nocardia mastitis in dairy herds in Nova Scotia. The data were collected by on-farm interviews with owners of 54 case and 54 control herds. Logistic regression was used to study risk factors. The use of dry cow products containing neomycin, including two specific dry cow products, was strongly associated with a diagnosis of Nocardia mastitis in a herd. Other factors which increased the risk of Nocardia mastitis were higher levels of production, larger herd size, and a large percentage of cows treated with dry cow products. These results are compared to results from a similar study carried out in Ontario. PMID:17423896

  3. 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

  4. Prevalence of enterohemorrhagic Escherichia coli O157:H7 in a survey of dairy herds.

    PubMed Central

    Zhao, T; Doyle, M P; Shere, J; Garber, L

    1995-01-01

    The prevalence of Escherichia coli O157:H7 in dairy herds is poorly understood, even though young dairy animals have been reported to be a host. From February to May 1993, 662 fecal samples from 50 control herds in 14 states, and from June to August 1993, 303 fecal samples from 14 case herds in 11 states were collected for isolation of E. coli O157:H7. Case herds were those in which E. coli O157:H7 was isolated from preweaned calves in a previous U.S. Department of Agriculture study, whereas control herds from which E. coli O157:H7 had not been isolated previously were randomly selected from the same states as case herds. Among the control herds, E. coli O157:H7 was isolated from 6 of 399 calves (1.5%) that were between 24 h old and the age of weaning and from 13 of 263 calves (4.9%) that were between the ages of weaning and 4 months. Eleven of 50 control herds (22%) were positive. Among the case herds, E. coli O157:H7 was isolated from 5 of 171 calves (2.9%) that were between 24 h old and the age of weaning and from 7 of 132 calves (5.3%) that were between the ages of weaning and 4 months. Seven of 14 case herds (50%) were positive. Sixteen of 31 isolates were obtained by direct plating, with populations ranging from 10(3) to 10(5) CFU/g. Fifteen of 31 isolates were isolated by enrichment only. Nineteen of the isolates produced both verocytotoxin 1 (VT-1) and VT-2, whereas 12 produced VT-2 only. PMID:7747951

  5. Management characteristics, lameness, and body injuries of dairy cattle housed in high-performance dairy herds in Wisconsin.

    PubMed

    Cook, N B; Hess, J P; Foy, M R; Bennett, T B; Brotzman, R L

    2016-07-01

    The objective of this study was to benchmark the prevalence of lameness, hock and knee injuries, and neck and back injuries among high-performance, freestall-housed dairy herds in Wisconsin. A random selection of 66 herds with 200 or more cows was derived from herds that clustered with high performance in year 2011 Dairy Herd Improvement records for milk production, udder health, reproduction, and other health parameters. Herds were surveyed to collect information about management, facilities, and well-being. Well-being measures were obtained through direct observation of the high-producing mature cow group, surveying 9,690 cows in total. Total herd size averaged (mean ± standard deviation) 851±717 cows, ranging 203 to 2,966 cows, with an energy-corrected milk production of 40.1±4.4kg/cow per day. Prevalence of clinical lameness (5-point scale, locomotion score ≥3) and severe lameness (locomotion score ≥4) averaged 13.2±7.3 and 2.5±2.7%, respectively. The prevalence of all hock and knee injuries, including hair loss, swelling, and ulceration, was similar at 50.3±28.3 and 53.0±24.0%, respectively. Severe (swelling and ulceration) hock and knee injury prevalence were 12.2±15.3 and 6.2±5.5%, respectively. The prevalence of all neck injuries (including hair loss, swelling and ulceration) was 8.6±16.3%; whereas the prevalence of swollen or abraded necks was low, averaging 2.0±4.1%. Back injuries (proportion of cows with missing or abraded spinous processes, hooks, or pins) followed a similar trend with a low mean prevalence of 3.6±3.4%. Overall, physical well-being characteristics of this selection of high-producing, freestall-housed dairy herds provide evidence that lameness and injury are not inevitable consequences of the confinement housing of large numbers of dairy cattle. In particular, lameness prevalence rivals that of lower-production grazing systems. However, hock and other injury risk remains a concern that can be addressed through a choice in

  6. Applied epidemiology: another tool in dairy herd health programs?

    PubMed

    Frankena, K; Noordhuizen, J P; Stassen, E N

    1994-01-01

    Data bases of herd health programs concern data from individual animals mainly. Several parameters that determine herd performance can be calculated from these programs, and by comparing actual values with standard values, areas for further improvement of health (and production) can be advised. However, such advice is usually not backed up by the proper statistical analyses. Moreover, data concerning the environment of the animals are not present and hence advice concerning multifactorial diseases are based on common knowledge and experience. Veterinary epidemiology offers methods that might improve the value of herd health programs by identification and quantification of factors and conditions contributing to multifactorial disease occurrence. Implementation of these methods within herd health programs will lead to more scientifically sound advice.

  7. Serological and molecular detection of Mycobacterium avium subsp. paratuberculosis in cattle of dairy herds in Colombia.

    PubMed

    Fernández-Silva, Jorge Arturo; Abdulmawjood, Amir; Akineden, Omer; Bülte, Michael

    2011-12-01

    The objective of this study is the detection of Mycobacterium avium subsp. paratuberculosis (MAP) by serum enzyme-linked immunosorbent assay (ELISA), fecal polymerase chain reaction (PCR), and fecal culture in Colombian dairy herds. Serum and fecal samples from asymptomatic cows (n = 307) of 14 dairy herds were tested for MAP by an unabsorbed ELISA test (ELISA-A). Serum and fecal samples from positive ELISA-A animals (n = 31) were further tested by an absorbed ELISA test (ELISA-B) and PCR. Fecal samples from animals of herds positive by ELISA-A and PCR (n = 105) were inoculated onto three different culture media. ELISA-A produced positive results in 10% of the serum samples and 71% of the herds. ELISA-B and PCR results were positive in two and six serum and fecal samples from positive ELISA-A animals, respectively. Fecal samples were negative for MAP on all culture media. The results of this study confirmed the presence of MAP in local dairy herds and the difficulties of MAP detection in asymptomatic animals by ELISA, PCR, and fecal culture.

  8. 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.

  9. Antimicrobial resistance of Salmonella and E. coli from Pennsylvania dairy herds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Antimicrobial resistance in bacterial pathogens is an increasing public health concern. The objective of this study was to examine antimicrobial resistance in Salmonella and E. coli isolates from Pennsylvania dairy herds. Manure composite samples were collected from 76 farms: on each farm one sample...

  10. 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...

  11. 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...

  12. 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.

  13. Bulk milk ELISA and the diagnosis of parasite infections in dairy herds: a review

    PubMed Central

    2013-01-01

    The bulk milk enzyme-linked immune sorbent assay (ELISA) is a rapid and inexpensive method of assessing herd exposure to pathogens that is increasingly being used for the diagnosis of parasite infections in dairy herds. In this paper, with the dairy herd health veterinarian in mind, we review the principles of the assay and the recent literature on the potential role of bulk milk ELISA for the diagnosis of ostertagiosis, fasciolosis, parasitic bronchitis due to cattle lung worm and neosporosis. It is generally accepted that assay results reflect exposure to the parasite rather than the presence of active infection. Bulk milk ELISA can be a useful tool for the veterinary practitioner as a component of a herd health monitoring programme or in the context of a herd health investigation. It can also play a role in regional or national surveillance programmes. However, the results need to be interpreted within the context of the herd-specific health management, the milk production pattern and the parasite life cycle. PMID:23883526

  14. Bulk milk ELISA and the diagnosis of parasite infections in dairy herds: a review.

    PubMed

    Sekiya, Mary; Zintl, Annetta; Doherty, Michael L

    2013-07-25

    The bulk milk enzyme-linked immune sorbent assay (ELISA) is a rapid and inexpensive method of assessing herd exposure to pathogens that is increasingly being used for the diagnosis of parasite infections in dairy herds. In this paper, with the dairy herd health veterinarian in mind, we review the principles of the assay and the recent literature on the potential role of bulk milk ELISA for the diagnosis of ostertagiosis, fasciolosis, parasitic bronchitis due to cattle lung worm and neosporosis. It is generally accepted that assay results reflect exposure to the parasite rather than the presence of active infection. Bulk milk ELISA can be a useful tool for the veterinary practitioner as a component of a herd health monitoring programme or in the context of a herd health investigation. It can also play a role in regional or national surveillance programmes. However, the results need to be interpreted within the context of the herd-specific health management, the milk production pattern and the parasite life cycle.

  15. 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.

  16. A partnership of universities and agri-business for an effective dairy herd management learning experience for undergraduates: the Dairy Challenge.

    PubMed

    Weber Nielsen, M S; Domecq, J J; Davis, L E; Beede, D K; Budine, M; Martsolf, F

    2003-03-01

    The Dairy Challenge contest allows undergraduate students to apply knowledge gained in the classroom in an evaluation of the management practices of commercial dairy farms. University faculty partnered with industry representatives to develop the competition. Participants in the Dairy Challenge do the following: 1) critically evaluate dairy herd management practices and make recommendations for improvements; 2) visit local dairy farms and gain knowledge of different farms' management practices; 3) meet and interact with potential employers from the dairy industry during the contest; 4) evaluate herd records and utilize knowledge of dairy herd management software and computer presentation tools; 5) test their speaking, presentation, and problem-solving skills; and 6) work as a team to build consensus and tag-team speaking formats. Teams of four undergraduate students critically evaluate a commercial dairy farm using herd records, a description of farm operations, and tour of the farm facilities. The farmer answers questions pertaining to management of the farm in a group interview with all teams and in a separate interview with each individual team. Teams give a 20-min presentation that is scored on the description and assessment of the management practices and recommendations for improvements in management and facilities. Additionally, scoring is based on apparent level of preparation, speaking, presentation skills, and responses to judges' questions. The judges are university specialists and dairy industry professionals. This capstone experience allows students to interact with dairy farmers and representatives from the dairy industry and expands their knowledge and skills gained during their academic career.

  17. 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.

  18. Evaluation of udder health parameters and risk factors for clinical mastitis in Dutch dairy herds in the context of a restricted antimicrobial usage policy.

    PubMed

    Santman-Berends, I M G A; Swinkels, J M; Lam, T J G M; Keurentjes, J; van Schaik, G

    2016-04-01

    Recently, many changes have been implemented in Dutch dairy herds. Herd sizes have increased and antimicrobial use has been reduced. Certain types of antimicrobials can only be used in specific circumstances, and the preventive use of antimicrobials in dry cows is prohibited. The aim of this study was to quantify clinical mastitis (CM), subclinical mastitis (SCM), and risk factors associated with CM in Dutch dairy herds in 2013, in the context of these changes. For this study, 240 dairy herds were randomly selected from farms that participated in test-day milk recording, used a conventional milking system, and agreed to participate in the study. Eventually, 233 Dutch dairy farmers had complete records of CM in their herds in 2013 and 224 of these farmers completed a questionnaire on management factors potentially associated with CM. All participating farmers gave consent to use their routinely collected herd data such as test-day records and cow identification and registration data. Clinical and subclinical mastitis incidence rate (CMI and SCMI, respectively) per 100 cows per year, subclinical mastitis prevalence, and average bulk tank milk somatic cell count were obtained for 2013. The risk factor analysis was conducted using a generalized linear model with a log link function and a negative binomial distribution on herd level in Stata 13.1. A median CMI of 28.6 per 100 cows at risk per year, SCMI of 70.1 per 100 cows at risk per year, SCM prevalence of 15.8%, and bulk tank milk somatic cell count of 171 × 10(3) cells/mL were observed in 2013. Factors that were significantly associated with a higher CMI were cleaning slatted floors only once per day compared with more than 4 times a day (i.e., mechanical), a higher percentage of Holstein Friesian cows present in the herd, treating less than 50% of the cows with CM with antimicrobials, postmilking teat disinfection, and treatment of cows with elevated somatic cell count with antimicrobials. The results of this

  19. Bovine rotavirus strains circulating in beef and dairy herds in Argentina from 2004 to 2010.

    PubMed

    Badaracco, A; Garaicoechea, L; Rodríguez, D; Uriarte, E Louge; Odeón, A; Bilbao, G; Galarza, R; Abdala, A; Fernandez, F; Parreño, V

    2012-08-17

    Bovine Group A Rotavirus (RVA) is one of the main causes of neonatal calf diarrhea worldwide. The present study reports the genotyping of bovine RVA strains circulating in Argentinean cattle from 2004 to 2010. Additionally, a new set of typing primers was designed and tested to differentiate between G8 and G6 (lineage III and IV) RVA strains. Bovine RVA was detected in 30% (435/1462) of the tested samples, corresponding to 49% (207/423) of the studied outbreaks with a similar detection rates in beef (53%; 67/127) and dairy herds (52%; 65/126). The RVA strains circulating in Argentinean cattle belonged to the common bovine genotypes G6 (lineages III and IV), G8, G10, P[5] and P[11]. A different RVA G/P-genotype distribution was found between the exploitation types, with the combination G6(IV)P[5] being by fare the most prevalent RVA strain in beef herds (58%), whereas a more even distribution of G6(III)P[11] (15%), G10P[11] (17%), G6(IV)P[5] (14%), and G6(IV)P[11] (6%) RVA strains was detected in dairy herds. G8 RVA strains were found in two dairy farms in calves co-infected with G8+G6(III)P[11]. A high percentage of co-infections and co-circulation of RVA strains with different genotypes during the same outbreak were registered in both exploitation types (20% of the outbreaks from beef herds and 23% from dairy herds), indicating a potential environment for reassortment. This finding is significant because G10P[11] and G6(III)P[11] strains may possess zoonotic potential. Continuous surveillance of the RVA strains circulating in livestock provides valuable information for a better understanding of rotavirus ecology and epidemiology.

  20. Q Fever Dairy Herd Status Determination Based on Serological and Molecular Analysis of Bulk Tank Milk.

    PubMed

    Anastácio, S; Carolino, N; Sidi-Boumedine, K; da Silva, G J

    2016-04-01

    Ruminants are recognized as the main reservoirs of Coxiella burnetii. EFSA highlighted the lack of knowledge about Q fever prevalence in many European countries. A cross-sectional study was carried out in randomly selected dairy herds (n = 109) from central Portugal to screen for C. burnetii infection and to correlate it with herd factors. Bulk tank milk (BTM) samples from cattle (n = 45) and small ruminant (n = 64) herds were tested by ELISA and PCR. The apparent seroprevalence of Q fever was estimated in 45.9% (95% CI: 36.3-55.7) being higher in small ruminants (51.6; 95% CI: 39.6-63.4) than in cattle (37.8; 95% CI: 25.1-52.4). The shedding of C. burnetii in BTM was detected in 11.9% (95% CI: 7.1-19.4) of BTM, and it was higher in cattle (20%; 95% CI: 10.9-33.8) than in sheep and mixed herds (6.3%; 95% CI: 2.5-15). A high bacterial load (≥ 3 × 10(3) bacteria/ml) was observed in 85% of PCR-positive BTM. A significant correlation was found between the bacterial load and positive samples on ELISA (P < 0.001). Antibody positivity was significantly associated with the increased herd size (P < 0.01) and the occurrence of abortion (P < 0.05), whereas the shedding of C. burnetii was significantly associated with the report of infertility (P < 0.05). The results highlight that serological and molecular methods in combination are a useful tool to screen for Q fever and to clarify the herd infection status. The shedding of C. burnetii through milk is important, especially in dairy cattle, and thus, the role of milk as a potential source of infection among dairy workers should not be neglected. To our knowledge, this is the first study reporting C. burnetii infection in dairy livestock in Portugal showing that Q fever is significant in dairy herds, leading to economic losses and being a risk for public health, which highlights the need of implementation of control measures.

  1. Clinical and subclinical bovine leukemia virus infection in a dairy cattle herd in Zambia.

    PubMed

    Pandey, Girja S; Simulundu, Edgar; Mwiinga, Danstan; Samui, Kenny L; Mweene, Aaron S; Kajihara, Masahiro; Mangani, Alfred; Mwenda, Racheal; Ndebe, Joseph; Konnai, Satoru; Takada, Ayato

    2017-04-01

    Bovine leukemia virus (BLV) causes enzootic bovine leucosis (EBL) and is responsible for substantial economic losses in cattle globally. However, information in Africa on the disease is limited. Here, based on clinical, hematological, pathological and molecular analyses, two clinical cases of EBL were confirmed in a dairy cattle herd in Zambia. In contrast, proviral DNA was detected by PCR in five apparently healthy cows from the same herd, suggesting subclinical BLV infection. Phylogenetic analysis of the env gene showed that the identified BLV clustered with Eurasian genotype 4 strains. This is the first report of confirmed EBL in Zambia.

  2. 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

  3. Organic dairy farmers put more emphasis on production traits than conventional farmers.

    PubMed

    Slagboom, M; Kargo, M; Edwards, D; Sørensen, A C; Thomasen, J R; Hjortø, L

    2016-12-01

    The overall aim of this research was to characterize the preferences of Danish dairy farmers for improvements in breeding goal traits. The specific aims were (1) to investigate the presence of heterogeneity in farmers' preferences by means of cluster analysis, and (2) to associate these clusters with herd characteristics and production systems (organic or conventional). We established a web-based survey to characterize the preferences of farmers for improvements in 10 traits, by means of pairwise rankings. We also collected a considerable number of herd characteristics. Overall, 106 organic farmers and 290 conventional farmers answered the survey, all with Holstein cows. The most preferred trait improvement was cow fertility, and the least preferred was calving difficulty. By means of cluster analysis, we identified 4 distinct clusters of farmers and named them according to the trait improvements that were most preferred: Health and Fertility, Production and Udder Health, Survival, and Fertility and Production. Some herd characteristics differed between clusters; for example, farmers in the Survival cluster had twice the percentage of dead cows in their herds compared with the other clusters, and farmers that gave the highest ranking to cow and heifer fertility had the lowest conception rate in their herds. This finding suggests that farmers prefer to improve traits that are more problematic in their herd. The proportion of organic and conventional farmers also differed between clusters; we found a higher proportion of organic farmers in the production-based clusters. When we analyzed organic and conventional data separately, we found that organic farmers ranked production traits higher than conventional farmers. The herds of organic farmers had lower milk yields and lower disease incidences, which might explain the high ranking of milk production and the low ranking of disease traits. This study shows that heterogeneity exists in farmers' preferences for

  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. Monitoring indices of cow comfort in free-stall-housed dairy herds.

    PubMed

    Cook, N B; Bennett, T B; Nordlund, K V

    2005-11-01

    Indices of cow comfort are used widely by consultants in the dairy industry, with a general understanding that they are representative of lying behavior. This study examines the influence of stall base type (sand or a geotextile mattress filled with rubber crumbs) and time of measurement on 4 indices of comfort collected at hourly intervals in 12 herds, aligned by morning and afternoon milking. Stall base type significantly influenced all indices of comfort. For example, the least squares mean (SE) cow comfort index (proportion of cows touching a stall that are lying down) was 0.76 (0.015) in herds with mattresses compared with 0.86 (0.015) in herds with sand stalls. Significant hourly variation was also identified suggesting that timing of measurement is important. None of the indices of cow comfort derived from the high-yielding group pen was associated with the mean 24-h lying time of 10 sentinel cows whose time budgets were known in each herd. However, the cow comfort index was associated with the herd mean 24-h stall standing time, with the strongest relationships occurring 2 h before the morning and afternoon milking, when stall base type did not significantly influence the association. When measured at these times, we recommend use of the stall standing index (proportion of cows touching a stall that are standing), with values greater than 0.20 being associated with abnormally long herd mean stall standing times greater than 2 h/d.

  6. Nitrate toxicosis in beef and dairy cattle herds due to contamination of drinking water and whey.

    PubMed

    Yeruham, I; Shlosberg, A; Hanji, V; Bellaiche, M; Marcus, M; Liberboim, M

    1997-10-01

    Four cases of rarely reported nitrate toxicosis due to contamination of drinking water or whey were recorded in 2 beef and 2 dairy cattle herds. In the cases associated with water contamination, water containing ammonium nitrate as a fertilizer for irrigating orchards accidentally entered drinking water troughs for cattle through malfunctioning 1-way valves. The whey contamination in 1 instance was caused by transportation in containers which contained traces of concentrated ammonium nitrate; the 2nd case was induced by whey derived from the production of a specialty cheese produced by the incorporation of nitrate. Mortality occurred in 2 herds and abortions in the 2 other herds. Affected cows responded well to treatment, but some animals remained in a deteriorated physical condition for several months.

  7. An observational study of Corynebacterium bovis in selected Ontario dairy herds.

    PubMed Central

    Brooks, B W; Barnum, D A; Meek, A H

    1983-01-01

    An observational study of Corynebacterium bovis was conducted in 74 Ontario dairy herds. The levels of infection with C. bovis were 19.9, 36.2 and 85.6% at the quarter, cow and herd level, respectively. Teat disinfection was found to be the variable best able to distinguish between herds with a high or low C. bovis quarter infection rate. Mean total milk somatic cell counts for 1103 quarters and 107 cows infected with only C. bovis ranged between 150,000 and 200,000/mL and were significantly higher than for uninfected quarters or cows. The rate of infection with mastitis pathogens was not significantly different in quarters previously colonized with only C. bovis compared to previously uninfected quarters. PMID:6831308

  8. 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

  9. 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...

  10. Sources other than unused sawdust can introduce Klebsiella pneumoniae into dairy herds.

    PubMed

    Verbist, B; Piessens, V; Van Nuffel, A; De Vuyst, L; Heyndrickx, M; Herman, L; Van Coillie, E; De Vliegher, S

    2011-06-01

    A longitudinal study was carried out to detect intramammary infections caused by Klebsiella pneumoniae and to identify potential sources of this bacterial species in the environment of the cows. The study was performed in 6 well-managed Belgian dairy herds from May 2008 to May 2009. Monthly (n=13), unused and used sawdust bedding samples as well as individual quarter milk and feces samples were collected from 10 randomly selected cohort cows in each herd. Cases of clinical mastitis of all lactating cows in the 6 herds were also sampled (n=64). From the 3,518 collected samples, 153 K. pneumoniae isolates were obtained, of which 2 originated from milk (clinical mastitis cases). In feces (n=728), used bedding (n=73), and unused bedding (n=73), respectively, 125 (17.2%), 20 (27.4%), and 6 (8.2%) isolates were found. The isolates were fingerprinted by means of pulsed field gel electrophoresis. In total, 109 different pulsotypes were differentiated, indicating a high degree of genetic diversity within the isolates. All isolates from unused bedding belonged to pulsotypes other than those from the other sources, suggesting that sources other than unused sawdust may introduce K. pneumoniae into the herd. Only 2 pulsotypes contained isolates originating from different sources. Pulsotype 10 was found in milk and used bedding and pulsotype 21 was found in feces and used bedding. The 2 milk isolates originated from 2 cows in the same herd but they belonged to a different pulsotype. The results indicate that K. pneumoniae can be prevalent in the environment without causing significant mastitis problems. Most cows were shedding K. pneumoniae in feces, substantiating findings under very different conditions (i.e., American dairy herds). Contamination of used bedding in the cubicles with K. pneumoniae from feces was confirmed, whereas unused bedding was not an important source of K. pneumoniae for the environment of the cows.

  11. 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

  12. 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.

  13. Occurrence of methicillin-resistant Staphylococcus aureus in dairy cattle herds, related swine farms, and humans in contact with herds.

    PubMed

    Locatelli, C; Cremonesi, P; Caprioli, A; Carfora, V; Ianzano, A; Barberio, A; Morandi, S; Casula, A; Castiglioni, B; Bronzo, V; Moroni, P

    2017-01-01

    In this study we investigated the circulation of methicillin-resistant Staphylococcus aureus (MRSA) in 2 dairy cattle farms (farm A and B), previously identified as MRSA-positive in bulk tank milk samples, and epidemiologically related to swine farms. Collected specimens included quarter milk samples and nasal swabs from dairy cows, pig nasal swabs collected at both the farm and slaughterhouse level, environmental dust samples, and human nasal swabs from the farms' owners and workers. The prevalence of MRSA was estimated at the herd level by testing quarter milk samples. The prevalence of MRSA was 4.8% (3/63; 95% confidence interval=0-10.2%) and 60% (33/55; 95% confidence interval=47.05-72.95) in farm A and B, respectively. In farm A, MRSA was also isolated from humans, pigs sampled at both farm and slaughterhouse level, and from environmental samples collected at the pig facilities. The dairy cattle facilities of farm A tested negative for MRSA. In farm B, MRSA was isolated from environmental dust samples in both the cattle and pig facilities, whereas nasal swabs collected from cows and from humans tested negative. Sixty-three selected MRSA isolates obtained from different sources in farm A and B were genetically characterized by multilocus sequence typing, spa-typing, ribosomal spacer-PCR, and also tested for the presence of specific virulence genes and for their phenotypical antimicrobial susceptibility by broth microdilution method. Different clonal complex (CC) and spa-types were identified, including CC398, CC97, and CC1, CC already reported in livestock animals in Italy. The MRSA isolates from quarter milk of farm A and B mostly belonged to CC97 and CC398, respectively. Both lineages were also identified in humans in farm A. The CC97 and CC398 quarter milk isolates were also identified as genotype GTBE and GTAF by ribosomal spacer-PCR respectively, belonging to distinct clusters with specific virulence and resistance patterns. The GTBE and GTAF clusters also

  14. 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

    2016-01-02

    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.

  15. Application of a Dot Blot Hybridization Platform to Assess Streptococcus uberis Population Structure in Dairy Herds

    PubMed Central

    Albuquerque, Pedro; Ribeiro, Niza; Almeida, Alexandre; Panschin, Irena; Porfirio, Afonso; Vales, Marta; Diniz, Francisca; Madeira, Helena; Tavares, Fernando

    2017-01-01

    Streptococcus uberis is considered one of the most important pathogens associated with bovine mastitis. While traditionally acknowledged as an environmental pathogen, S. uberis has been shown to adopt a contagious epidemiological pattern in several dairy herds. Since different control strategies are employed depending on the mode of transmission, in-depth studies of S. uberis populations are essential to determine the best practices to control this pathogen. In this work, we optimized and validated a dot blot platform, combined with automatic image analysis, to rapidly assess the population structure of infective S. uberis, and evaluated its efficiency when compared to multilocus sequence analysis (MLSA) genotyping. Two dairy herds with prevalent S. uberis infections were followed in a 6 month period, in order to collect and characterize isolates from cows with persistent infections. These herds, located in Portugal (Barcelos and Maia regions), had similar management practices, with the herd from Barcelos being smaller and having a better milking parlor management, since infected cow segregation was immediate. A total of 54 S. uberis isolates were obtained from 24 different cows from the two herds. To overcome operator-dependent analysis of the dot blots and increase the technique's consistency and reliability, the hybridization signals were converted into probability values, with average probabilities higher than 0.5 being considered positive results. These data allowed to confirm the isolates' identity as S. uberis using taxa-specific markers and to determine the presence of virulence- and antibiotic resistance-related genes. In addition, MLSA allowed to disclose the most prevalent S. uberis clonal lineages in both herds. Seven different clusters were identified, with Barcelos showing a high clonal diversity and Maia a dominant lineage infecting most cows, suggesting distinct epidemiological patterns, with S. uberis displaying an environmental or contagious

  16. 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).

  17. Housing, Feeding and Management of Calves and Replacement Heifers in Swedish Dairy Herds

    PubMed Central

    Pettersson, K; Svensson, C; Liberg, P

    2001-01-01

    A questionnaire was sent to 1500 randomly selected dairy herds in Sweden, asking for general information about the herds, including routines from birth to first calving and also routines at breeding, calving and during the grazing period. Fifty-eight percent of the questionnaires were returned. The preweaned calves were kept in individual calf pens in 68% and in group housing systems in 28% of the herds. Pens with slatted floors were the main housing system for replacement heifers from weaning to breeding, and tie stalls from breeding to first calving. Whole milk was used in 44% and milk replacements in 42% of the herds. The calves received, as a median, 2.5 litres of milk per meal and 2 meals per day. The median age at weaning was 8 weeks. Age was the single most common criteria used for deciding both weaning and breeding time. The median age when the heifers were first turned out to pasture was 6 months. Prophylactic anthelmintic treatment was used by 65% of the herds. The most common diet for replacement heifers before calving was a combination of grain, hay and silage. PMID:11957375

  18. Schmallenberg virus in Dutch dairy herds: potential risk factors for high within-herd seroprevalence and malformations in calves, and its impact on productivity.

    PubMed

    Veldhuis, A M B; Carp-van Dijken, S; van Wuijckhuise, L; Witteveen, G; van Schaik, G

    2014-01-31

    In November 2011, the new orthobunyavirus Schmallenberg virus (SBV) was identified in dairy cows that had induced fever, drop in milk production and diarrhoea in the Netherlands (Muskens et al., 2012. Tijdschrift voor Diergeneeskunde 137, 112-115) and a drop in milk production in cows in Northwestern Germany (Hoffmann et al., 2012. Emerging Infectious Diseases 18 (3), 469-472), in August/September 2011. This study aimed at quantifying risk factors for high within-herd prevalence of SBV and SBV-induced malformations in newborn calves in dairy herds in the Netherlands. Additionally, the within-herd impact of SBV infection on mortality rates and milk production was estimated. A case-control design was used, including 75 clinically affected case herds and 74 control herds. Control herds were selected based on absence of malformations in newborn calves and anomalies in reproductive performance. SBV-specific within-herd seroprevalences were estimated. Risk factors for high within-herd SBV seroprevalence (>50%) and the probability of malformed newborn calves in a herd were quantified. In addition, within-herd impact of SBV with regard to milk production and mortality was estimated. Animal-level seroprevalence was 84.4% (95% confidence interval (CI): 70.8-92.3) in case herds and 75.8% (95% CI: 67.5-82.5) in control herds. Control herds that were completely free from SBV were not present in the study. Herds that were grazed in 2011 had an increased odds (OR 9.9; 95% CI: 2.4-41.2)) of a high seroprevalence (>50%) compared to herds that were kept indoors. Also, when grazing was applied in 2011, the odds of malformations in newborn calves tended to be 2.6 times higher compared to herds in which cattle were kept indoors. Incidence of malformations in newborn calves at herd level was associated with both within-herd seroprevalence and clinical expression of the disease in adult cattle. The rate of vertical transmission of SBV to the fetus once a dam gets infected seemed low. A

  19. Factors associated with variation in bulk tank milk Mycoplasma bovis antibody-ELISA results in dairy herds.

    PubMed

    Petersen, Mette B; Krogh, Kaspar; Nielsen, Liza R

    2016-05-01

    The relevance and limitations for using measurements of antibodies against Mycoplasma bovis in bulk tank milk (BTM) as a potentially cost-effective diagnostic tool for herd classification has not been evaluated before. Assuming that an increasing or high seroprevalence is a result of on-going or recent spread of M. bovis in a dairy herd, we tested the hypothesis that increasing prevalence of antibody-positive cows and young stock are associated with increasing BTM antibody ELISA values against M. bovis in Danish dairy herds with different courses of M. bovis infection. Furthermore, we tested whether herd size was associated with variations in the BTM responses. Thirty-nine Danish dairy herds selected to represent 4 different herd-level infection groups [8 control herds, 14 acute outbreak herds, 7 herds with previous outbreaks, and 10 herds with elevated BTM ELISA-values directed against M. bovis (>64% optical density measurement)] were visited 4 to 5 times, approximately 3mo apart. At each visit, 65 young stock were blood sampled. At the milk recording date closest to the herd visit date, 50 milk recording samples from individual lactating cows were randomly selected. In addition, a BTM sample was collected as a representative sample directly from the bulk tank by the dairies' milk truck drivers as part of the mandatory milk quality-control scheme. Blood and milk samples were tested for antibodies against M. bovis with a commercially available ELISA test (Bio-X BIO K 302, Bio-X Diagnostics, Rochefort, Belgium). A linear mixed effects model was used to analyze the effects of the prevalence of antibody-positive lactating cows and young stock and herd size on the BTM M. bovis ELISA results. Herd was included as a random effect to account for clustering of BTM samples originating from the same herd. Increasing prevalence of antibody-positive lactating cows was the only variable associated with increasing M. bovis BTM ELISA optical density measurement. In contrast, the

  20. 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.

  1. Quantification of vertical and horizontal transmission of Neospora caninum infection in Dutch dairy herds.

    PubMed

    Bartels, Chris J M; Huinink, Irene; Beiboer, Marten L; van Schaik, Gerdien; Wouda, Willem; Dijkstra, Thomas; Stegeman, Arjan

    2007-09-01

    Ninety-six of 108 randomly selected Dutch dairy herds had one or more cows with a positive serostatus for N. caninum. In these 96 herds, we have quantified the probabilities of vertical transmission (VT) and horizontal transmission (HT) of N. caninum infection by combining serostatus and pedigree data in 4091 dam-daughter pairs. The probability of animals infected by vertical transmission during pregnancy (Prob(VT)) was calculated as the proportion of seropositive daughters among daughters of seropositive dams. The probability of animals infected by horizontal transmission (Prob(HT)) was the proportion of seropositive daughters among daughters of seronegative dams. These probabilities were calculated after the frequencies of observed dam-daughter combinations were corrected for (1) imperfect test-characteristics, (2) underestimation of horizontal transmission in situations that seronegative dams were horizontally infected after the birth of their daughters and (3) overestimation of vertical transmission in situations that seronegative daughters born from seropositive dams were horizontally infected. The incidence rate for horizontal transmission was calculated based on Prob(HT) and the average age of the animals in these herds. Based on the analysis of dam-daughter serology, Prob(VT) was 61.8% (95% CI: 57.5-66.0%) and Prob(HT) was 3.3% (95% CI: 2.7-3.9%). After adjusting the observed frequencies for imperfect test-characteristics, underestimation of horizontal transmission and overestimation of vertical transmission, Prob(VT) decreased to 44.9% (95% CI: 40.0-49.9%) while Prob(HT) increased to 4.5% (95% CI: 3.9-5.2%). Prob(HT) corresponded with an incidence rate for horizontal transmission of 1.4 (95% CI: 1.2-1.7) infections per 100 cow-years at risk. When stratifying herds for the presence of farm dogs, Prob(HT) was higher (5.5% (95% CI: 4.6-6.4%)) in herds with farm dogs than in herds without farm dogs (2.3% (95% CI: 1.5-3.4%)). When stratifying for within-herd

  2. Comparing ELISA test-positive prevalence, risk factors and management recommendations for Johne's disease prevention between organic and conventional dairy farms in Ontario, Canada.

    PubMed

    Pieper, Laura; Sorge, Ulrike S; DeVries, Trevor; Godkin, Ann; Lissemore, Kerry; Kelton, David

    2015-11-01

    Johne's disease (JD) is a chronic, infectious disease in cattle. Between 2010 and 2013, a voluntary JD control program was successfully launched in Ontario, Canada, including a Risk Assessment and Management Plan (RAMP) and JD ELISA testing of the entire milking herd. Over the last decade, the organic dairy sector has been growing. However, organic farming regulations and philosophies may influence the risk for JD transmission on Ontario organic dairy farms. The aim of this cross-sectional study was to investigate differences in JD ELISA test positive prevalence, risk factors for JD and recommendations for JD prevention between organic and conventional dairy herds in Ontario. RAMP results (i.e. RAMP scores and recommendations) and ELISA results were available for 2103 dairy herds, including 42 organic herds. If available, additional data on milk production, milk quality, and herd characteristics were gathered. Organic and conventional herds had a similar herd-level JD ELISA test-positive prevalence (26.2% and 27.2%, respectively). Organic herds (4.2%) had a higher within-herd JD ELISA test-positive prevalence compared to conventional herds (2.3%) if they had at least one JD test-positive animal on the farm. Organic farms had lower risk scores for biosecurity (9 points lower), and higher scores in the calving (7 points higher) and the calf-rearing management areas (4 points higher). After accounting for RAMP score, organic farms received fewer recommendations for the calving management area (Odds Ratio=0.41) and more recommendations in the adult cow management area (Odds Ratio=2.70). A zero-inflated negative binomial model was built with purchase of animals and the herd size included in the logistic portion of the model. Herd type (organic or conventional), colostrum and milk feeding practices, average bulk tank somatic cell count, and presence of non-Holstein breeds were included in the negative binomial portion of the model. Organic farms had a higher number of

  3. Effect of human-animal relationship and management on udder health in Swiss dairy herds.

    PubMed

    Ivemeyer, S; Knierim, U; Waiblinger, S

    2011-12-01

    In a cross-sectional study, we investigated the effects of human-animal interactions and management factors on udder health in 46 Swiss dairy herds living in loose-housing systems on farms that participated in the Swiss dairy farm network "pro-Q." The human-animal relationship was measured by observing milkers' behavior, cows' behavior during milking, and cows' avoidance distance in the barn. Management factors were assessed by questionnaire-guided interviews and observations. Udder health was evaluated using indicators that were calculated from milk recording data over a period of 1 yr before assessment: (1) average somatic cell scores (SCS) per herd and (2) incidence of new infections per herd (NEWINF); and indicators that were calculated from quarter milk samples of all lactating cows at the time of assessment: (3) prevalence of quarters with elevated somatic cell counts (>100,000 cells/mL; %Q>100) and (4) prevalence of mastitis quarters (>100,000 cells/mL and culturally positive; %Qmast). After univariate preselection of associated factors, multivariable linear regression models were calculated at the herd level and a multilevel regression model was calculated at the herd and cow levels for SCS. Among all of the human-animal relationship factors, the most dominant predictor for SCS, %Q>100, and %Qmast was the percentage of positive interactions of milkers with the cows in relation to all of their interactions during milking. Furthermore, a higher prevalence of fearful cows in the herd (with an avoidance distance >1 m) was associated with a higher %Q>100. In herds with a higher NEWINF, incidents of cows kicking during milking occurred more frequently. Concerning management as well as farm and herd characteristics, the following mastitis risk factors were found: (1) breed, especially Holstein with regard to SCS, NEWINF, and %Qmast; (2) high age in terms of lactation number with regard to SCS and %Qmast; (3) high amount of new infections of a cow over 1 yr with

  4. Novel approaches to assess the quality of fertility data stored in dairy herd management software.

    PubMed

    Hermans, K; Waegeman, W; Opsomer, G; Van Ranst, B; De Koster, J; Van Eetvelde, M; Hostens, M

    2017-03-02

    Scientific journals and popular press magazines are littered with articles in which the authors use data from dairy herd management software. Almost none of such papers include data cleaning and data quality assessment in their study design despite this being a very critical step during data mining. This paper presents 2 novel data cleaning methods that permit identification of animals with good and bad data quality. The first method is a deterministic or rule-based data cleaning method. Reproduction and mutation or life-changing events such as birth and death were converted to a symbolic (alphabetical letter) representation and split into triplets (3-letter code). The triplets were manually labeled as physiologically correct, suspicious, or impossible. The deterministic data cleaning method was applied to assess the quality of data stored in dairy herd management from 26 farms enrolled in the herd health management program from the Faculty of Veterinary Medicine Ghent University, Belgium. In total, 150,443 triplets were created, 65.4% were labeled as correct, 17.4% as suspicious, and 17.2% as impossible. The second method, a probabilistic method, uses a machine learning algorithm (random forests) to predict the correctness of fertility and mutation events in an early stage of data cleaning. The prediction accuracy of the random forests algorithm was compared with a classical linear statistical method (penalized logistic regression), outperforming the latter substantially, with a superior receiver operating characteristic curve and a higher accuracy (89 vs. 72%). From those results, we conclude that the triplet method can be used to assess the quality of reproduction data stored in dairy herd management software and that a machine learning technique such as random forests is capable of predicting the correctness of fertility data.

  5. 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.

  6. 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.

  7. Dairy cow cleanliness and milk quality on organic and conventional farms in the UK.

    PubMed

    Ellis, Kathryn A; Innocent, Giles T; Mihm, Monika; Cripps, Peter; McLean, W Graham; Howard, C Vyvyan; Grove-White, Dai

    2007-08-01

    A subjective cow cleanliness scoring system was validated and used to assess the cleanliness score of dairy cows at different times in the year. A longitudinal study followed a number of farms from summer to winter, and a larger, cross-sectional study assessed a greater number of farms during the housed winter period. The scoring system was demonstrated to be both a repeatable and practical technique to use on-farm and showed that cows become dirtier in the transition from summer grazing to winter housing. Although farming system (organic or conventional) had no effect on cow cleanliness when cows were at grass, when housed in the winter, organic cows were significantly more likely to be cleaner. There was a link between cow cleanliness scores and milk quality, with herds having lower bulk tank somatic cell counts (BTSCC) tending to have a lower (cleaner) median cow cleanliness score; with this relationship strongest for the organic herds. There was no significant link between cleanliness score and Bactoscan (BS) count or clinical mastitis incidence. No major mastitis pathogens were cultured from bulk tank milk samples from the quartile of herds with the cleanest cows in contrast to the quartile of herds with the dirtiest cows, where significant mastitis pathogens were cultured. Based on this study, all farms, especially organic systems, should attempt to keep cows clean as part of subclinical mastitis control.

  8. Herd-level association between antimicrobial use and antimicrobial resistance in bovine mastitis Staphylococcus aureus isolates on Canadian dairy farms.

    PubMed

    Saini, V; McClure, J T; Scholl, D T; DeVries, T J; Barkema, H W

    2012-04-01

    Surveillance of antimicrobial use and resistance is needed to manage antimicrobial resistance in bacteria. In this study, data were collected on antimicrobial use and resistance in Staphylococcus aureus (n=562), isolated from intramammary infections and (sub)clinical mastitis cases on 89 dairy farms in 4 regions of Canada [Alberta, Ontario, Québec, and the Maritime Provinces (Prince Edward Island, Nova Scotia, and New Brunswick)]. Dairy producers were asked to deposit empty drug containers into specially provided receptacles, and antimicrobial drug use rate was calculated to quantify antimicrobial use. Minimum inhibitory concentrations were determined using the Sensititer bovine mastitis plate system (TREK Diagnostic Systems Inc., Cleveland, OH), containing antimicrobials commonly used for mastitis treatment and control. Multivariable logistic regression models were built to determine herd-level risk factors of penicillin, ampicillin, pirlimycin, penicillin-novobiocin combination, tetracycline and sulfadimethoxine resistance in Staph. aureus isolates. Intramammary administration of the penicillin-novobiocin combination for dry cow therapy was associated with penicillin and ampicillin resistance [odds ratio (OR): 2.17 and 3.10, respectively]. Systemic administration of penicillin was associated with penicillin resistance (OR: 1.63). Intramammary administration of pirlimycin for lactating cow mastitis treatment was associated with pirlimycin resistance as well (OR: 2.07). Average herd parity was associated with ampicillin and tetracycline resistance (OR: 3.88 and 0.02, respectively). Average herd size was also associated with tetracycline resistance (OR: 1.02). Dairy herds in the Maritime region had higher odds of penicillin and lower odds of ampicillin resistance than dairy herds in Québec (OR: 2.18 and 0.19, respectively). Alberta dairy herds had lower odds of ampicillin and sulfadimethoxine resistance than dairy herds in Québec (OR: 0.04 and 0.08, respectively

  9. The economic effects of whole-herd versus selective anthelmintic treatment strategies in dairy cows.

    PubMed

    Charlier, J; Levecke, B; Devleesschauwer, B; Vercruysse, J; Hogeveen, H

    2012-06-01

    Current control practices against gastrointestinal nematodes in dairy cows rely strongly on anthelmintic use. To reduce the development of anthelmintic resistance or disposition of drug residues in the environment, novel control approaches are currently proposed that target anthelmintic treatment to individual animals instead of the whole herd. However, such selective treatment strategies come with additional costs for labor and diagnostics and, so far, no studies have addressed whether they could be economically sustainable. The objectives of this study were to (1) investigate the economic effects at farm level of whole-herd versus more selective anthelmintic treatment strategies in adult dairy cows, and (2) determine how these economic effects depend on level of infection and herd size. A Monte Carlo simulation, fed by current epidemiological and economical knowledge, was used to estimate the expected economic effects and possible variation of different control strategies under Belgian conditions. Four treatment strategies were compared with a baseline situation in which no treatments were applied: whole herd at calving (S1), selective at calving with (S2) or without (S3) treatment of the first-calf cows, and whole-herd when animals are moved from grazing to the barn in the fall (housing treatment, S4). The benefit per lactation for an average dairy herd varied between -$2 and $131 (average $64) for S1, between -$2 and $127 (average $62) for S2, between -$17 and $104 (average $43) for S3, and between -$41 and $72 (average $15) for S4. The farmer's risk associated with any treatment strategy, as indicated by the width of the 95% credible intervals of economic benefit of anthelmintic treatment, decreased with increasing level of exposure, as assessed by bulk tank milk ELISA. The order of the different strategies when sorted by expected benefit was robust to changes in economic input parameters. We conclude that, on average, strategies applying anthelmintic

  10. 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.

  11. Incidence rate of pathogen-specific clinical mastitis on conventional and organic Canadian dairy farms.

    PubMed

    Levison, L J; Miller-Cushon, E K; Tucker, A L; Bergeron, R; Leslie, K E; Barkema, H W; DeVries, T J

    2016-02-01

    Mastitis is a common and costly production disease on dairy farms. In Canada, the incidence rate of clinical mastitis (IRCM) has been determined for conventionally managed dairy farms; however, no studies to date have assessed rates in organically managed systems. The objectives of this observational study were (1) to determine the producer-reported IRCM and predominant pathogen types on conventional and organic dairy farms in Southern Ontario, Canada, and (2) to evaluate the association of both mean overall IRCM and pathogen-specific IRCM with management system, housing type, and pasture access. Data from 59 dairy farms in Southern Ontario, Canada, distributed across conventional (n=41) and organic management (n=18) systems, were collected from April 2011 to May 2012. In addition to management system, farms were categorized by housing method (loose or tie-stall) and pasture access for lactating cows. Participating producers identified and collected samples from 936 cases of clinical mastitis. The most frequently isolated mastitis pathogens were coagulase-negative staphylococci, Bacillus spp., Streptococcus spp., Staphylococcus aureus, and Escherichia coli. The IRCM was higher on conventional farms than organic (23.7 vs. 13.2 cases per 100 cow-years) and was not associated with housing type (loose or tie-stall), pasture access, or herd-average milk yield. Bulk tank somatic cell count tended to be lower on conventional farms than organic (222,000 vs. 272,000 cells/mL). Pathogen-specific IRCM attributed to Staph. aureus, Bacillus spp., and E. coli was greater on conventional than organic farms, but was not associated with housing or any other factors. In conclusion, organic management was associated with reduced overall and pathogen-specific IRCM.

  12. The definition of acidosis in dairy herds predominantly fed on pasture and concentrates.

    PubMed

    Bramley, E; Lean, I J; Fulkerson, W J; Stevenson, M A; Rabiee, A R; Costa, N D

    2008-01-01

    This cross-sectional survey examined the prevalence of ruminal acidosis and the effects of acidosis on the production of dairy cattle. Eight fresh cows, 3 primiparous and 5 multiparous (< 100 d in milk), were selected randomly from each of 100 dairy herds in 5 regions of Australia. Rumen fluid was obtained from each cow by rumenocentesis and a stomach tube, and samples were tested for pH. Stomach tube rumen fluid samples were analyzed for volatile fatty acid, ammonia, and D-lactate concentrations. On the basis of the results of all assays, cows were categorized into 3 distinct categories (categories 1, 2, and 3) by cluster analysis. The percentages of cattle in categories 1, 2, and 3 were 10.2, 29.9, and 59.9%, respectively. Mean rumen pH for categories 1, 2, and 3 were 5.74 +/- 0.47, 6.18 +/- 0.44, and 6.33 +/- 0.43, respectively. Biochemically, categories 1, 2, and 3 were characterized, respectively, as follows: mean total VFA concentration (mM), 100.74 +/- 23.22, 94.79 +/- 18.13, and 62.81 +/- 15.65; mean ammonia concentration (mM), 2.46 +/- 2.02, 7.79 +/- 3.75, and 3.64 +/- 2.03; and mean D-lactate concentration (mM), 0.34 +/- 0.86, 0.28 +/- 0.97, and 0.12 +/- 0.51. Category 1 cows had higher propionate, valerate, isovalerate, and caproate concentrations and were of lower parity than cows in other categories. Cows in category 1 had higher milk production but lower milk fat content than category 2 cows. Herds were assigned to 1 of 3 groups according to the numbers of cows assigned to each category. Herds with > or = 3 of the 8 cows in category 1 were classified as acidotic. Herds with > or = 3 of the 8 cows in category 2 were classified as having suboptimal rumen function, and herds with > or = 3 of the 8 cows in category 3 were classified as normal. Herds that had 3 or more of the 8 cows in category 1 (acidotic herds) had diets with higher energy and nonfiber carbohydrate contents and a lower neutral detergent fiber content than herds with a high prevalence of

  13. Effects of bovine necrotic vulvovaginitis on productivity in a dairy herd in Israel.

    PubMed

    Blum, S; Mazuz, M; Brenner, J; Friedgut, O; Koren, O; Goshen, T; Elad, D

    2008-05-01

    Bovine necrotic vulvovaginitis (BNVV) is characterized by the development of a necrotic vulvovaginal lesion, almost exclusively in post-parturient first-lactation cows, associated with Porphyromonas levii. The scope of this survey was to evaluate the impact of BNVV on herd productivity as a means to rationally evaluate the resources that should be allocated in dealing with the syndrome. During an outbreak of BNVV in a dairy herd, following the introduction of a large number of cows from another farm, the impact of the animals' origin (local or transferred) and BNVV (positive or negative) upon involuntary culling rate, milk yield and days between pregnancies were assessed. The results indicated that the number of days between pregnancies was significantly higher in first-lactation cows with BNVV but was not influenced by the other independent variables. None of the other variables included in this survey had any effect on the involuntary culling rate and milk yield.

  14. Prevalence of Bovine Viral Diarrhoea Virus antibodies among the industrial dairy cattle herds in suburb of Mashhad-Iran.

    PubMed

    Talebkhan Garoussi, M; Haghparast, A; Hajenejad, M R

    2009-04-01

    Mashhad is a major dairy production in Iran. The subject of this study was to survey the seroprevalence of Bovine Viral Diarrhea Virus (BVDV) infection using an indirect Enzyme-linked immunosorbent assay (ELISA) test in industrial dairy cattle herds in suburb of Mashhad-Iran. Totally, 141 serum samples were tested. None of the herds had been vaccinated against BVDV. Commercial indirect ELISA kit was used. The herds divided to 3 sizes as cow population. They were included: small, medium and large herds. Data were analyzed using Chi-square test. Ninety-seven (68.79%) cows were ELISA seropositive. However, the true BVDV seroprevalence was 72.25%. All of the herds were antibody positive against BVDV. The prevalence ranged from 66 to 100% within the herds. There were no significant differences between the presence of antibodies to BVDV and the herd size (P > 0.05). The prevalence in animals lower than 2 years old differed significantly with cows higher than 2 years old (P < 0.05). According to the results, it is concluded that it is likely the presence of persistently infection (PI) animal(s) within the herds in suburb of Mashhad-Iran, which is responsible for the presence antibody.

  15. Comparison of selected animal observations and management practices used to assess welfare of calves and adult dairy cows on organic and conventional dairy farms.

    PubMed

    Bergman, M A; Richert, R M; Cicconi-Hogan, K M; Gamroth, M J; Schukken, Y H; Stiglbauer, K E; Ruegg, P L

    2014-07-01

    Differences in adoption of selected practices used in welfare assessment and audit programs were contrasted among organic (ORG; n=192) herds and similarly sized conventional grazing herds (CON-GR; n=36), and conventional nongrazing herds (CON-NG; n=64). Criteria from 3 programs were assessed: American Humane Association Animal Welfare Standards for Dairy Cattle, Farmers Assuring Responsible Management (FARM), and the Canadian Codes of Practice (CCP). Data were collected by trained study personnel during a herd visit and included information about neonatal care, dehorning, pain relief, calf nutrition, weaning, record keeping, use of veterinarians, and animal observations. Associations of management type (ORG, CON-GR, or CON-NG) with adoption of selected practice were assessed. Almost all farms (97%) met criteria suggested for age at weaning but fewer CON-NG farmers weaned calves at ≥5 wk of age compared with ORG and CON-GR farmers. Only 23% of farms met program requirements for use of pain relief during dehorning, and fewer CON-NG farmers used pain relief for calves after dehorning compared with ORG and CON-GR farmers. Calves on ORG farms were fed a greater volume of milk and were weaned at an older age than calves on CON-GR and CON-NG farms. Calves on CON-GR farms were dehorned at a younger age compared with calves on ORG and CON-NG farms. The calving area was shared with lactating cows for a larger proportion of ORG herds compared with conventional herds. About 30% of herds met welfare program criteria for body condition score but only about 20% met criteria for animal hygiene scores. The least proportion of cows with hock lesions was observed on ORG farms. Regular use of veterinarians was infrequent for ORG herds. Results of this study indicate that most of the organic and conventional farms enrolled in this study would have been unlikely to achieve many criteria of audit and assessment programs currently used in the US dairy industry.

  16. A Robust Statistical Model to Predict the Future Value of the Milk Production of Dairy Cows Using Herd Recording Data

    PubMed Central

    Græsbøll, Kaare; Kirkeby, Carsten; Nielsen, Søren Saxmose; Halasa, Tariq; Toft, Nils; Christiansen, Lasse Engbo

    2017-01-01

    The future value of an individual dairy cow depends greatly on its projected milk yield. In developed countries with developed dairy industry infrastructures, facilities exist to record individual cow production and reproduction outcomes consistently and accurately. Accurate prediction of the future value of a dairy cow requires further detailed knowledge of the costs associated with feed, management practices, production systems, and disease. Here, we present a method to predict the future value of the milk production of a dairy cow based on herd recording data only. The method consists of several steps to evaluate lifetime milk production and individual cow somatic cell counts and to finally predict the average production for each day that the cow is alive. Herd recording data from 610 Danish Holstein herds were used to train and test a model predicting milk production (including factors associated with milk yield, somatic cell count, and the survival of individual cows). All estimated parameters were either herd- or cow-specific. The model prediction deviated, on average, less than 0.5 kg from the future average milk production of dairy cows in multiple herds after adjusting for the effect of somatic cell count. We conclude that estimates of future average production can be used on a day-to-day basis to rank cows for culling, or can be implemented in simulation models of within-herd disease spread to make operational decisions, such as culling versus treatment. An advantage of the approach presented in this paper is that it requires no specific knowledge of disease status or any other information beyond herd recorded milk yields, somatic cell counts, and reproductive status. PMID:28261585

  17. Impact of processing on in vitro digestion of milk from grazing organic and confined conventional herds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Debate on differences between milk from grazing and non-grazing cows has not addressed the effects that standard processing may have on milk digestibility. In this study, raw milk from grazing organic (ORG) and non-grazing conventional (CONV) herds was adjusted to 0 and 3.25% fat and processed as fo...

  18. 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.

  19. The Application of Bulk Tank Somatic Cell Counts to Monitoring Mastitis Levels in Dairy Herds

    PubMed Central

    Meek, A.H.; Barnum, D.A.

    1982-01-01

    The objective of this study was to investigate the feasibility of developing a system whereby measurements taken on bulk tank milk samples could be used to monitor the level of subclinical mastitis in dairy herds. The variables that were examined were the logarithmically transformed total somatic cell counts and percentages of cell volume in channel 8 (volumes from 89.2 to 178.3 µm3), the presence or absence of Streptococcus agalactiae and various husbandry/management factors including herdsize and the use of teat dips. Each of the use of actual monthly and rolling average bulk tank cell count determinations was investigated. It was found that the inclusion of all variables resulted in a correct classification of approximately 85% of herds and that no improvement was achieved by the use of rolling as opposed to actual monthly values. The inclusion of various husbandry/management practices improved the percentage correct classification to some extent over that achieved by the sole use of total somatic cell counts and percentages of cell volume in channel 8 when the herds were grouped on the basis of quarter infection rate (<10%, >10%) but not in the case of the cow infection rate categories (<20%, >20%). The use of both total cell counts and percentages of cell volume in channel 8 did not improve the overall predictive value over that achieved by the sole use of percentage of cell volume in channel 8 in the case of the quarter infection rate groupings but did to some extent in the case of the cow infection rate groupings. When the classification functions were applied prospectively and considering combinations of the two cell count determinations only, it was found that they were able to correctly classify, on the basis of the quarter infection rate groupings, approximately 75% of the study herds. It is concluded that the system described herein has limited application as a basis for selecting problem herds. PMID:7042053

  20. 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.

  1. 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

  2. Study on prevalence of bovine viral diarrhoea virus (BVDV) antibodies in 29 Italian dairy herds with reproductive problems.

    PubMed

    Luzzago, C; Piccinini, R; Zepponi, A; Zecconi, A

    1999-01-01

    An epidemiological survey on prevalence distribution of antibodies to BVDV was carried out in dairy cattle herds during 1995-1996 in northern Italy. A total of 704 serum samples from 29 non-vaccinated herds reported to have reproductive problems were tested for serum neutralising antibodies. In each herd, sampling was based on the stratification by age into five classes (< 6 months old calves, 6-12 months old calves, pregnant heifers, uniparous, pluriparous). Overall, 53.3% of samples were serologically positive, with the lowest ratio in 6-12 months old calves (37.9%) and the highest in pluriparous cows (71.2%).

  3. Interrelationships between herd-level reproductive performance measures based on intervals from initiation of the breeding program in year-round and seasonal calving dairy herds.

    PubMed

    Morton, J M

    2010-03-01

    In year-round calving herds, reproductive performance has traditionally been described in relation to each cow's calving date. This research described reproductive performance in year-round and seasonal calving dairy herds using herd-level measures based on interval from each cow's initiation of breeding program date, and assessed interrelationships between such measures. A large, prospective, single cohort study, implemented in 1997 and 1998, included 29,327 cows from 167 Australian dairy herds. Herd reproductive performance was described using 2 measures of primary importance to herd managers: the proportion of cows that became pregnant by 6wk after their initiation of breeding program date (6-wk pregnancy rate) and the proportion of cows that were nonpregnant 21wk after their initiation of breeding program date (21-wk nonpregnancy rate). Measures that contribute to these primary measures (secondary measures) were calculated for each herd for both the first and second 3-wk periods of each cow's breeding program; submission rates were calculated as proportions of cows that were inseminated at least once in the 3-wk period, and conception rates were calculated as the proportions of inseminations in the 3-wk period that resulted in pregnancy. The individual herd was the unit of analysis. The study results indicate that high submission rates are essential if herd reproductive performance is to be achieved. Six-week pregnancy rate was predicted to increase by 6 to 8 percentage points following a 10-percentage-point increase in submission rates in both 3-wk periods, and by 6 to 10 percentage points following a 10-percentage-point increase in conception rates. Submission rates were more variable than conception rates, indicating that managers may be able to achieve large increases in submission rates more easily than substantial increases in conception rates. However, the predicted benefits of increasing submission rates were greatest when conception rates were high and

  4. Pre-Calving and Calving Management Practices in Dairy Herds with a History of High or Low Bovine Perinatal Mortality

    PubMed Central

    Mee, John F.; Grant, Jim; Sánchez-Miguel, Cosme; Doherty, Michael

    2013-01-01

    Simple Summary Mortality of full-term calves at calving is an increasing problem in dairy industries internationally. Multiple herd management factors contribute to such losses. This case-control study identified factors which differed between herds with high and low calf mortality. These included breeding, dietary, health and calving factors. It was concluded that calving, not pre-calving, management appears to be the most important area of concern in herds with high perinatal mortality. This indicates that farmers and their veterinarians need to focus on calving management when investigating such problems and when attempting to reduce losses in herds with high rates of bovine perinatal mortality. Abstract Bovine perinatal mortality is an increasing problem in dairy industries internationally. The objective of this study was to determine the risk factors associated with high and low herd-level calf mortality. Thirty herds with a history of either high (case) or low (control) calf mortality were recruited. A herd-level questionnaire was used to gather information on management practices likely to impact bovine perinatal mortality. The questionnaire was divided into four subsections dealing with pre-calving (breeding, diet and body condition score, endemic infectious diseases) and calving factors. Most of the significant differences between case and control herds were found in calving management. For example, in case herds, pregnant cattle were less likely to be moved to the calving unit two or more days and more likely to be moved less than 12 hours pre-calving, they were also less likely to calve in group-calving facilities and their calves were more likely to receive intranasal or hypothermal resuscitation. These management procedures may cause social isolation and periparturient psychogenic uterine atony leading to dystocia, more weak calves requiring resuscitation and high perinatal calf mortality. The key finding is that calving, not pre-calving, management

  5. 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.

  6. Managerial determinants of intramammary coliform and environmental streptococci infections in Ohio dairy herds.

    PubMed

    Bartlett, P C; Miller, G Y; Lance, S E; Heider, L E

    1992-05-01

    Forty-eight dairy herds in Ohio were selected as a stratified random sample for participation in a disease monitoring study to relate the prevalence of IMI with coliform and environmental streptococci to herd management and environmental conditions. Management and environmental conditions were assessed by farm inspection and by an interview with the dairy producers. A separate analysis for each independent variable identified many potential disease determinants. A multivariable analysis of a covariance model to predict the prevalence of coliforms had 6 model df (R2 = .47). Increased prevalence of coliform infection was associated with an increased amount of milk remaining in the udder after milking, use of free stalls, regular use of a running water wash, increased person hours per cow spent milking, and poor sanitation. The multivariable model for environmental streptococci used 5 model df (R2 = .51). Increased prevalence of environmental streptococci was associated with poor sanitation, increased number of days dry, use of tie stalls, no use of a shared wash cloth, and no use of an individual dry cloth.

  7. 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

  8. 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.

  9. 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

  10. 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

  11. 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

  12. Molecular typing of isolates obtained from aborted foetuses in Brucella-free Holstein dairy cattle herd after immunisation with Brucella abortus RB51 vaccine in Egypt.

    PubMed

    Wareth, Gamal; Melzer, Falk; Böttcher, Denny; El-Diasty, Mohamed; El-Beskawy, Mohamed; Rasheed, Nesma; Schmoock, Gernot; Roesler, Uwe; Sprague, Lisa D; Neubauer, Heinrich

    2016-12-01

    Bovine brucellosis is endemic in Egypt in spite of application of surveillance and control measures. An increase of abortions was reported in a Holstein dairy cattle herd with 600 animals in Damietta governorate in Egypt after immunisation with Brucella (B.) abortus RB51 vaccine. Twenty one (10.6%) of 197 vaccinated cows aborted after 3 months. All aborted cows had been tested seronegative for brucellosis in the past 3 years. B. abortus was isolated from four foetuses. Conventional biochemical and bacteriological identification and polymerase chain reaction (PCR) confirmed two B. abortus biovar (bv.) 1 smooth and two B. abortus rough strains. None of the B. abortus isolates were identified as RB51. Genotyping analysis by multiple locus of variable number tandem repeats analysis based on 16 markers (MLVA-16) revealed two different profiles with low genetic diversity. B. abortus bv1 was introduced in the herd and caused abortions.

  13. 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.

  14. 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.

  15. An epidemiologic study of disease in 32 registered Holstein dairy herds in British Columbia.

    PubMed Central

    van Dorp, R T; Martin, S W; Shoukri, M M; Noordhuizen, J P; Dekkers, J C

    1999-01-01

    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. PMID:10480460

  16. 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.

  17. 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

  18. Prevalence of bovine viral diarrhoea virus antibodies in bulk tank milk of industrial dairy cattle herds in suburb of Mashhad-Iran.

    PubMed

    Garoussi, M Talebkhan; Haghparast, A; Estajee, H

    2008-04-17

    Bulk milk for the presence of antibodies against bovine viral diarrhea virus (BVDV) from 38 industrial dairy cattle herds complexes with 250-3000 Holstein dairy cows in suburb of Mashhad-Iran was tested. None of the herds were vaccinated against BVDV. Commercial indirect ELISA-kit for the detection of specific antibodies was used. The result could be read visually where the optical density (OD) was measured at 450 nm. The percent positivity (PP) values >or=7 and <7 interpreted positive and negative, respectively. According to this study the apparent and the true prevalence of BVDV antibody-positive herds was 89.47 and 93.98%, respectively. The range of PP was 1.59-107.66 among the herds. The OD in 52.63% bulk milk of the herds was very high. It is concluded that exposure to BVD virus was widely distributed in the dairy cattle herds in suburb of Mashhad-Iran.

  19. Influence of milking method, disinfection and herd management practices on bulk tank milk somatic cell counts in tropical dairy herds in Colombia.

    PubMed

    Reyes, J; Sanchez, J; Stryhn, H; Ortiz, T; Olivera, M; Keefe, G P

    2017-02-01

    The aims of this study were to evaluate the effects of milking method, disinfection practices and other management factors on the bulk tank milk somatic cell count (BTSCC) in tropical dairy herds and to examine potential interactions with time. One hundred and thirty farms in the Northern region of Antioquia, Colombia, were visited once per month for 24 months. A two level linear mixed model for repeated measures was used to assess the impact on log transformed BTSCC (lnBTSCC). The geometric mean of the BTSCC for all herds was 262,330 cells/mL. The two-level linear mixed model showed that lnBTSCCs in hand milked herds were significantly higher than in machine milked herds. Fore-stripping corresponded with a 27% increase in lnBTSCC and failing to post-dip corresponded with a 45% increase in lnBTSCC. The two way interactions of sampling month with milking method, singeing udders and pre-dipping were significant. The lowest predicted lnBTSCC was observed in machine milked herds that practised both pre-dipping and singeing of udders. This study suggests that milking procedures and disinfection practices can interact with time and have substantial effects on lnBTSCC.

  20. 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

  1. Comparative risk assessment for new cow-level Mycobacterium avium ssp. paratuberculosis infections between 3 dairy production types: Organic, conventional, and conventional-grazing systems.

    PubMed

    Beaver, A; Ruegg, P L; Gröhn, Y T; Schukken, Y H

    2016-12-01

    Johne's disease, a granulomatous enteritis of ruminant animals, is a hidden threat on dairy farms, adversely affecting animal welfare as well as herd productivity. Control programs in the United States advocate for specific management practices to temper the spread of the causal organism (Mycobacterium avium ssp. paratuberculosis, MAP), such as improving calving area hygiene and limiting introduction of replacement stock with unknown infection status. A need remains for direct exploration of Johne's disease prevention strategies in the United States with respect to production type. Alongside the growing demand for organic products, the safety of organic dairy practices with respect to MAP control is warranted. Further, conventional herds for which organic practices such as pasture grazing are used should be situated within the risk spectrum. We developed a risk assessment model using the US Voluntary Bovine Johne's Disease Control Program as a framework, with the goal of evaluating the risk of new cow-level MAP infections. A total of 292 organic and conventional farms in 3 states were surveyed on management practices, and an overall analysis was conducted in which each farm was first scored on individual practices using a range of "no risk" to "high risk," according to the literature. The sum of all risk factors was then analyzed to quantify and compare the risk burden for each production type. Organic herds received higher overall risk scores compared with both conventional grazing and nongrazing subtypes. To identify which factors contributed to the overall increased risk for organic herds, the management practices were categorized and evaluated by logistic regression. We determined that the increased risk incurred by organic herds was predominantly due to decisions made in the calving area and preweaned calf group. However, although certain individual risk factors related to calf management are commonly involved in prevention strategies (e.g., cow

  2. 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

  3. Monitoring the bulk milk antibody response to bovine viral diarrhea in dairy herds vaccinated with inactivated vaccines.

    PubMed

    Gonzalez, A M; Arnaiz, I; Eiras, C; Camino, F; Sanjuán, M L; Yus, E; Diéguez, F J

    2014-01-01

    This study was designed to determine long-term responses in dairy herds after vaccination with 1 of 3 inactivated bovine viral diarrhea virus (BVDV) vaccines with regard to antibodies against p80 protein in bulk tank milk samples, as detected by ELISA. In the present study, 29 dairy herds were vaccinated with Bovilis BVD (MSD Animal Health, Milton Keynes, UK), 11 with Hiprabovis Balance (Laboratorios Hipra, Amer, Spain), and 9 with Pregsure BVD (Zoetis, Florham Park, NJ). In these herds, bulk tank milk samples were collected and examined at the time of the first vaccination and every 6 mo during a 3-yr period. Samples were analyzed with a commercial ELISA test for the p80 protein of BVDV. The results demonstrated that vaccination affected the level of antibodies against p80. Hence, vaccination status should be taken into consideration when interpreting bulk tank milk antibody tests.

  4. Management practices associated with the bulk tank milk prevalence of Mycoplasma spp. in dairy herds in Northwestern Portugal.

    PubMed

    Pinho, L; Thompson, G; Machado, M; Carvalheira, J

    2013-01-01

    The objective of this study was to evaluate the effect of some management practices on the prevalence of Mycoplasma spp. in Northwestern Portuguese dairy farms from bulk tank milk (BTM) samples. Additionally, the within-herd prevalence of Mycoplasma spp. was also determined, but only in BTM positive herds. From May 2007 to November 2008, 492 BTM samples from 164 dairies randomly chosen in a population of 1234 dairy farms were analyzed. Five herds (3.0%) had positive mycoplasmal culture results, from which 4 out of 164 (2.4%) were Mycoplasma bovis, with simultaneous presence of Mycoplasma bovigenitalium or Mycoplasma canadense in two of those samples. In one out of 164 (0.6%) herds Mycoplasma capricolum subsp. capricolum was also found. In BTM positive Mycoplasma spp. herds, the apparent intra-herd prevalence was low and varied between 2.5% and 4.5%. Multiple locus variable-number of tandem-repeat analysis was conducted in order to compare the genetic relationship between the isolates. Mycoplasma spp. was found to be present in cows with subclinical mastitis with or without California Mastitis Test positive results, hence all cows should be tested when the agent is isolated from bulk tank rather than selecting suspected cows. A multivariable logistic regression using the Firth's penalized maximum likelihood estimation was performed showing that increasing number of lactating cows (OR=1.05; P<0.01) was associated with a higher probability of isolating Mycoplasma spp. On the other hand, identifying problem cows was associated with a lower probability (OR=0.06; P<0.05). Particular importance was given to the prevalence of M. bovis, and the results obtained highlight the need to include this agent in mastitis control protocols in national dairies and in sanitary controls of transitioned animals between European countries.

  5. 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

  6. Short communication: Herd-level reproductive performance and its relationship with lameness and leg injuries in freestall dairy herds in the northeastern United States.

    PubMed

    Chapinal, N; von Keyserlingk, M A G; Cerri, R L A; Ito, K; Leblanc, S J; Weary, D M

    2013-01-01

    The objectives of this study were to describe herd-level reproductive outcomes and their associations with the prevalence of lameness, hock injuries and knee injuries in freestall dairy herds in the northeastern United States. Five reproductive outcomes (calving to conception interval, CCI; calving interval, CI; conception risk at the first artificial insemination, CR1; insemination rate, IR; and pregnancy rate, PR) were measured from Dairy Comp 305 (Valley Agricultural Software, Tulare, CA) for a 12-mo period for all multiparous cows in each of the 53 herds assessed. The prevalence of lameness, hock injuries, and knee injuries was assessed in 1 high-producing group. The means (± standard deviation) for the 5 reproductive outcomes were as follows: CCI = 128 ± 10 d, CI = 404 ± 10 d, CR1 = 36 ± 5%, IR = 60 ± 7%, and PR = 20 ± 3%. The average prevalence of clinical lameness, hock injuries, and knee injuries were 45 ± 20%, 58 ± 31%, and 16 ± 15%, respectively. Univariable associations between the reproductive outcomes and the prevalence of lameness and leg injuries were tested and significant predictors were submitted to a model that controlled for the confounding effects of herd size, 305-d mature equivalent milk production of the high-producing group, and use of deep bedding. A higher prevalence of lameness was associated with poorer reproductive performance, although the relationships were weak: herds with a higher prevalence of lameness had longer average CCI (slope estimate = 0.16 ± 0.07; R(2)= 0.09) and CI (slope estimate = 0.14 ± 0.07; R(2) = 0.07). These results indicate that management to reduce lameness may improve reproductive performance.

  7. Associations of risk factors with somatic cell count in bulk tank milk on organic and conventional dairy farms in the United States.

    PubMed

    Cicconi-Hogan, K M; Gamroth, M; Richert, R; Ruegg, P L; Stiglbauer, K E; Schukken, Y H

    2013-06-01

    In the past decade, the demand for organic agricultural products has increased rapidly in the United States and worldwide. Milk quality research is of major interest to both consumers and dairy farmers alike. However, scientific data on milk quality, herd management methods, and animal welfare on organic farms in the United States has been lacking before the research from this study. The objective of this study was to evaluate the association of bulk tank milk somatic cell count (SCC) with management characteristics on organic and conventional dairy farms in New York, Oregon, and Wisconsin. Data from similarly sized organic farms (n=192), conventional nongrazing farms (n=64), and conventional grazing farms (n=36) were collected at a single farm visit. Of the 292 farms visited, 290 bulk tank milk samples were collected. Overall, no difference in SCC was observed between the conventional and organic grazing systems. Two models were created to assess the effects of various management and herd characteristics on the logarithmic transformation of the SCC (LSCC), one using data from all herds and one using data from organic herds only. From the total herd model, more grain fed per cow per day was negatively associated with LSCC, whereas a positive bulk tank culture for Staphylococcus aureus and years that a farmer reported being in the dairy business were both positively associated with LSCC. In the organic herd model, a seasonal effect indicated that LSCC tended to increase in the summer and decrease in the winter. Grain fed per cow per day, the use of anionic salts in transition-cow diets, the use of gloves during milking, and regular use of a quarantine unit at milking were all negatively associated with LSCC. Similar to the total herd model, a Staph. aureus-positive bulk tank culture was positively associated with LSCC in the organic model. Standard plate count was also positively associated with LSCC in the organic model. Several variables that were associated with

  8. Relationships between fatty liver and fertility and some periparturient diseases in commercial Dutch dairy herds.

    PubMed

    Jorritsma, R; Jorritsma, H; Schukken, Y H; Wentink, G H

    2000-10-15

    Declining fertility in dairy cows is frequently suggested to arise from the occurrence of a more negative energy balance and/or the concomitant increased accumulation of triacylglycerol in the liver. Therefore, we performed a field study to assess the clinical effects of postpartum fatty liver in dairy cows on fertility and reproductive disease. Data were collected from 360 cows from nine dairy herds on fertility, diseases, and the liver triacylglycerol content on two occasions during lactation: 6 to 17 days and 38 to 50 days postpartum. The mean concentration of triacylglycerol in the liver was 54.6 mg/g from 6 to 17 days and 38.4 mg/g from 38 to 50 days postpartum. The probability of pregnancy was 30% lower for cows with higher contents of triacylglycerol in the liver compared to the probability for cows with low liver triacylglycerol (P = 0.049). The probability of estrus was also 35% lower for the cows with high triacylglycerol in the liver. This resulted in larger intervals between parturition and first heat and parturition and pregnancy for these cows. There was no effect observed on the first insemination conception rate. Given a certain level of triacylglycerol, recorded milk production had a positive effect on time to pregnancy. The incidences of endometritis, lochiometra and cystic ovarian follicles were not higher in cows with higher liver triacylglycerol contents. Endometritis was associated with a lower first insemination conception rate and more days open (chi2 = 4.26, P = 0.03 and T-test = -2.02, P= 0.04 respectively). We concluded that our results support the idea that differences in the negative energy balance or the accumulation of triacylglycerol in the liver of postpartum dairy cows affect fertility performance. The data also indicate that an increase in milk production has no negative impact on fertility as long as the amount of triacylglycerol in the liver remains the same.

  9. Effect of management practices on paratuberculosis prevalence in Danish dairy herds.

    PubMed

    Nielsen, S S; Toft, N

    2011-04-01

    A voluntary risk-based control program on paratuberculosis in dairy cattle was initiated in Denmark in 2006. Cows were categorized as high-risk (antibody-positive at least once within the last 3 tests) or low-risk animals based on the results of 3 to 4 annual milk ELISA detecting Mycobacterium avium ssp. paratuberculosis (MAP)-specific antibodies. High-risk animals require management practices aimed at decreasing calf exposure to MAP-contaminated colostrum and milk, and feces originating from these cows. Moreover, repeated test-positive cows are recommended for slaughter before next calving. The objective was to assess the effect of different management practices on the prevalence of MAP-specific antibodies. A questionnaire on management practices was distributed to 1,261 participating herds in December 2008. A total of 1,092 (87%) herd managers returned the questionnaire. Repeated prevalence data from 1,081 herds were available for a period up to 4.25 yr after the first test round. The changes in the prevalence of MAP-specific antibodies from the start of interventions were assessed using a hierarchical logistic model, where different management practices were assessed: a) culling of repeated test-positive cows, b) separation of high-risk from low-risk cows in calving areas, c) cleaning of calving areas after high-risk cows calved, d) removal of calves born to high-risk dams within 2h after calving, e) use of colostrum for feeding of heifer calves from low-risk cows only, f) use of waste milk for feeding of heifer calves from low-risk cows only, g) herd size, and h) proportion of purchased animals. Multivariable analyses suggested that only the proportion of purchased animals (>15% purchased animals as well as 0 to 15% purchased animals compared with no purchased animals in the herd), culling of repeated test-positive animals, and use of waste milk from specific cow groups influenced the decrease in prevalence of MAP-specific antibodies. The control program has

  10. Short communication: prevalence, risk factors, and a field scoring system for udder cleft dermatitis in Dutch dairy herds.

    PubMed

    Olde Riekerink, R G M; van Amersfort, K; Sampimon, O C; Hooijer, G A; Lam, T J G M

    2014-01-01

    Udder cleft dermatitis (UCD) is a well-known disorder in dairy cows. Veterinary literature about this subject, however, is scarce. The objectives of this study were to define a clinical scoring system for UCD, estimate the within-herd prevalence of UCD, and identify potential risk factors of UCD at cow and herd level. On 20 randomly selected dairy farms in the Netherlands, each lactating cow was photographed from a ventral, lateral, and caudal position. A scoring system with 6 categories of severity of UCD was proposed based on the ventral photographs. Cow measures such as udder width and depth, and front quarter attachment were determined from the lateral and caudal photographs. A questionnaire was conducted on each farm during farm visits. Udder cleft dermatitis, defined as a score 3 or higher, was detected in 5.2% of the 948 cows involved in this study. Within-herd prevalences of UCD ranged between 0 and 15% and UCD was found in 16 (80%) of the participating farms. Cows with a deep udder (relative to the hock), large front quarters, and a small angle between udder and abdominal wall were more likely to develop UCD. Production level and use of a footbath were identified as being positively associated with herd-level UCD prevalence. Herd size and average bulk milk somatic cell count did not seem to be associated with UCD prevalence. Because of the small herd sample size, no firm conclusions were drawn on herd-level risk factors. However, results from this study can be used in designing a future longitudinal UCD study. The prevalences of UCD found in the present study illustrate the current UCD situation in the Netherlands. Our results demonstrate that multiple potential risk factors of UCD could be identified at both the cow and herd level.

  11. 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

  12. Association between somatic cell count during the first lactation and the cumulative milk yield of cows in Irish dairy herds.

    PubMed

    Archer, S C; Mc Coy, F; Wapenaar, W; Green, M J

    2014-01-01

    Reduced potential milk yield is an important component of mastitis costs in dairy cows. The first aim of this study was to assess associations between somatic cell count (SCC) during the first lactation, and cumulative milk yield over the first lactation and subsequent lifetime of cows in Irish dairy herds. The second aim was to assess the association between SCC at 5 to 30d in milk during parity 1 (SCC1), and SCC over the entire first lactation for cows in Irish dairy herds. The data set studied included records from 51,483 cows in 5,900 herds. Somatic cell count throughout the first lactation was summarized using the geometric mean and variance of SCC. Data were analyzed using linear models that included random effects to account for the lack of independence between observations, and herd-level variation in coefficients. Models were developed in a Bayesian framework and parameters were estimated from 10,000 Markov chain Monte Carlo simulations. The final models were a good fit to the data. A 1-unit increase in mean natural logarithm SCC over the first lactation was associated with a median decrease in first lactation and lifetime milk yield of 135 and 1,663kg, respectively. A 1-unit increase in the variance of natural logarithm SCC over the first lactation was associated with a median decrease in lifetime milk yield of 719kg. To demonstrate the context of lifetime milk yield results, microsimulation was used to model the trajectory of individual cows and evaluate the expected outcomes for particular changes in herd-level geometric mean SCC over the first lactation. A 75% certainty of savings of at least €199/heifer in the herd was detected if herd-level geometric mean SCC over the first lactation was reduced from ≥120,000 to ≤72,000cells/mL. The association between SCC1 and SCC over the remainder of the first lactation was highly herd dependent, indicating that control measures for heifer mastitis should be preferentially targeted on an individual-herd

  13. Time to first calving and calving interval in bovine virus diarrhoea virus (BVDV) sero-converted dairy herds in Norway.

    PubMed

    Valle, P S; Martin, S W; Skjerve, E

    2001-09-20

    Dairy herds in Møre and Romsdal County, Norway (regarded as initially free from the bovine virus diarrhoea virus (BVDV) infection) were studied retrospectively from 1992 to 1996. The herd reproductive performance (time to first calving, calving interval, and number of breeding services) was investigated for a potential effect of BVDV sero-conversion. The herd culling pattern--possibly affecting the above measurements--was included for investigation. Two different statistical models were used: the generalised estimating equation (GEE) method and multilevel modelling using Gibbs sampling. Though slightly different estimates resulted, both models agreed on an effect of BVDV in the second year after sero-conversion on the herd average time to first calving by--on an average-- 14-16 days. In subsets of case herds testing positive for BVDV antibodies among young stock, the impact on time to first calving tended to be more pronounced by an additional increase of 18 days. No effect on the number of breeding services for heifers or cows was observed (indicating a need to search for other determinants than reduced conception risk). There appeared to be no effect of BVDV on the herd average calving interval. There was a tendency for a higher risk for reporting animals lost/died in sero-converted herds, which we believe might be related to the occurrence of mucosal disease.

  14. 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

  15. Herd monitoring to optimise fertility in the dairy cow: making the most of herd records, metabolic profiling and ultrasonography (research into practice).

    PubMed

    Smith, R F; Oultram, J; Dobson, H

    2014-05-01

    Fertility performance is intrinsically linked to the quality of the animal environment, overall management and nutrition. This review describes the use of dairy herd records, metabolic profiles and ultrasonographic findings at veterinary fertility examinations to monitor and manage dairy herd fertility. After calving, a cow has to overcome a series of physiological hurdles before establishing a pregnancy. The selection of timely key performance indicators (KPIs) that monitor specific events in the postpartum and service periods is vital to correctly identify problems and their potential causes that hopefully can be rectified. Cumulative sum charts are the timeliest monitors of efficiency of detection of oestrus, insemination outcome and relationship between postpartum events and fertility, with the point of inflection indicating when a change took place. Other KPIs use data from specific cohorts, adding an inherent delay to when change is indicated. Metabolic profiles and milk constituent data allow monitoring of nutritional adequacy and developments to offer new possibilities of on-farm systems for regular measurements of milk constituents (including progesterone) and energy status. Examination of the reproductive tract can be used to indicate individual and herd fertility status but the currently available detail is under used. Recent advances in ultrasonography can improve the diagnosis of reproductive tract pathophysiology still further but the clinical use of these methods in veterinary practice needs further evaluation. Development of new KPIs to exploit research findings are needed to ensure this knowledge is used to improve on-farm performance.

  16. Epidemiology and risk factors for exposure to gastrointestinal nematodes in dairy herds in northwestern Europe.

    PubMed

    Bennema, Sita C; Vercruysse, Jozef; Morgan, Eric; Stafford, Kathryn; Höglund, Johan; Demeler, Janina; von Samson-Himmelstjerna, Georg; Charlier, Johannes

    2010-10-29

    In this survey, the epidemiology of gastrointestinal (GI) nematodes in dairy herds in five northwestern European countries was studied using a standardized Ostertagia ostertagi ELISA applied on bulk-tank milk, and a common questionnaire. The levels of exposure to GI nematodes were high in Belgium, the UK and Ireland, intermediate in Germany and low in Sweden, with a mean (95% confidence interval) ELISA result (ODR) of 0.83 (0.82-0.84) in Belgium, 0.82 (0.79-0.84) in the UK and 0.80 (0.78-0.83) in Ireland; significantly higher than the mean ODR of 0.66 (0.65-0.68) in Germany and 0.52 (0.51-0.53) in Sweden. Taking into account previous literature, these regional differences are likely to be systematic. Regional variations in exposure were significantly explained by differences in management (grazing time per day, mowing, the months of turnout, housing and anthelmintic treatment). However, after controlling for these factors, significant regional differences in levels of exposure remained, suggesting an importance for climate (temperature, rainfall) and unmeasured management factors. This study emphasizes that GI nematode-induced production losses should be considered on a large percentage of northwest European dairy herds. Proposals are made for the development of region-specific monitoring and control strategies. Further advances in this area are likely to come from intervention studies that investigate the feasibility of control measures and from studies on the potential effects of climatic conditions on shifts in levels of exposure between years and regions.

  17. Detection and characterization of Salmonella typhimurium from a dairy herd in North Dakota.

    PubMed

    Nolan, L K; Giddings, C W; Boland, E W; Steffen, D J; Brown, J; Misek, A

    1995-01-01

    Nasal secretions, faecal samples and buffy coats were obtained from 102 cattle from a North Dakota dairy herd with a history of calf scours. Treated buffy coats, faecal samples and nasal secretions were inoculated into tetrathionate broth (TB), incubated at 37 degrees C overnight, and plated onto brilliant green agar medium with novobiocin (BGAN). The TB was left at room temperature for 5 days and then used to inoculate fresh TB. The fresh TB was incubated at 37 degrees C over night and plated onto BGAN medium. All the plates were incubated at 37 degrees C over night and observed for Salmonella-like growth. Suspect colonies were further tested and Salmonella isolates were serotyped by the National Veterinary Services laboratory. Twenty-two of the 36 calves sampled harboured S. typhimurium in their faeces, but no samples from cows were positive. No Salmonella were isolated from the buffy coats, but 4 calves were shown to have Salmonella in their nasal secretions. Extended enrichment of the faecal cultures in TB resulted in a significant increase in Salmonella isolations, although 2 samples were positive following the initial enrichment period and not after secondary enrichment. The typical Salmonella isolate detected from this herd contained a transmissible R-plasmid encoding resistance to tetracycline, kanamycin, sulphisoxazole and ampicillin. This study confirmed that delayed secondary enrichment in TB is superior to primary enrichment for detection of Salmonella from cattle.

  18. 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

  19. 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.

  20. 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.

  1. Development and daily management of an explicit strategy of nonuse of antimicrobial drugs in twelve Danish organic dairy herds.

    PubMed

    Vaarst, M; Bennedsgaard, T W; Klaas, I; Nissen, T B; Thamsborg, S M; Østergaard, S

    2006-05-01

    Promotion of animal health and well-being at the individual animal and herd level is an important goal in organic farming. At the same time, chemical products affecting the natural balance among living organisms are prohibited in all areas of the organic farm. From an animal welfare point of view, however, no animal must suffer. Therefore, veterinary drugs are allowed under the European Union's regulations for organic farming, despite the fact that they are powerful cell toxins affecting both pathogenic and necessary bacteria, and as such in organic terminology, are regarded as "chemical" or "artificial" products. In this article, we present and discuss interviews with 12 Danish organic dairy producers who claim that minimized use or nonuse of antimicrobial drugs is an explicit goal. The dairy producers were at different levels with regard to reduced antimicrobial treatment. An explicit strategy of no antimicrobial treatments is based primarily on a long-term effort to improve herd health, and secondarily, on finding alternative treatments for diseased animals. Improved hygiene, outdoor access, use of nursing cows, and blinding of chronic mastitis quarters were the main techniques in developing a strategy of not using antimicrobial treatments in the herd by dairy producers. Producers' perception of disease changed from something unavoidable to a disturbing break in the daily rhythm that often could have been avoided. Change toward a nonantimicrobial strategy was gradual and stepwise. All dairy producers in this study desired to preserve the possibility of using antimicrobial drugs in emergencies.

  2. 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

  3. 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

  4. Imbedding HACCP principles in dairy herd health and production management: case report on calf rearing.

    PubMed

    Boersema, Jsc; Noordhuizen, Jptm; Vieira, A; Lievaart, Jj; Baumgartner, W

    2008-09-01

    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.

  5. 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

  6. Assessment of selenium and vitamin E deficiencies in dairy herds and clinical disease in calves.

    PubMed

    Zust, J; Hrovatin, B; Simundić, B

    1996-10-19

    Because of the very low concentrations of selenium in the dry matter of grass, grass silage, hay and maize silage Slovenian dairy herds need to be supplemented with selenium. Selenium in the form of mineral and feed mixtures maintained adequate mean (sd) blood serum selenium concentrations of 43.9 (27.6) to 65.3 (18.5) micrograms/litre in lactating cows, but in late lactation and in the dry period when only mineral mixtures were used, about 60 per cent of the cows had marginal serum selenium concentrations, mainly because of the low intake of the mineral supplement. In 18 herds which were either unsupplemented or irregularly supplemented with selenium, the mean (sd) concentrations in blood serum were 13.7 (5.5) micrograms/litre and 17.4 (9.2) micrograms/litre, respectively, for selenium and 2.98 (2.72) mg/litre and 1.62 (1.73) mg/litre for vitamin E, indicating that under extensive farming conditions in Slovenia the lack of both micronutrients may be responsible for nutritional muscular dystrophy in calves. Among 37 clinical cases, cardiorespiratory signs predominated in 25 of the calves and skeletal myopathy was dominant in 12. A very low mean serum selenium concentration [9.7 (7.2) micrograms/litre] and typically high activities of aspartate aminotransferase (AST) [1125 (373) U/litre] and creatine kinase (CK) [9169 (3681) U/litre) were observed for the myocardial form of the disease, and 2797 (550) U/litre and 22,650 (13,500) U/litre were observed for the skeletal form of the disease. A highly significant (P < 0.0001) difference in the selenium concentration of liver dry matter between the regularly supplemented [402 (207) micrograms/kg] and irregularly supplemented [173 (69) micrograms/kg] herds was observed. If a minimum value of 300 micrograms/kg of liver dry matter is accepted as the criterion for the determination of adequate selenium status, 93 per cent of the samples from the irregularly supplemented herds were selenium deficient. A similar proportion was

  7. Association between stall surface and some animal welfare measurements in freestall dairy herds using recycled manure solids for bedding.

    PubMed

    Husfeldt, A W; Endres, M I

    2012-10-01

    The objective of this cross-sectional study was to investigate the association between stall surface and some animal welfare measurements in upper Midwest US dairy operations using recycled manure solids as bedding material. The study included 34 dairy operations with herd sizes ranging from 130 to 3,700 lactating cows. Forty-five percent of the herds had mattresses and 55% had deep-bedded stalls. Farms were visited once between July and October 2009. At the time of visit, at least 50% of the cows in each lactating pen were scored for locomotion, hygiene, and hock lesions. On-farm herd records were collected for the entire year and used to investigate mortality, culling, milk production, and mastitis incidence. Stall surface was associated with lameness and hock lesion prevalence. Lameness prevalence (locomotion score ≥ 3 on a 1 to 5 scale) was lower in deep-bedded freestalls (14.4%) than freestalls with mattresses (19.8%). Severe lameness prevalence (locomotion score ≥ 4) was also lower for cows housed in deep-bedded freestalls (3.6%) than for cows housed in freestalls with mattresses (5.9%). In addition, the prevalence of hock lesions (hock lesion scores ≥ 2 on a 1 to 3 scale, with 1=no lesion, 2=hair loss or mild lesion, and 3=swelling or severe lesion) and severe hock lesions (hock lesion score=3) was lower in herds with deep-bedded freestalls (49.4%; 6.4%) than in herds with mattresses (67.3%; 13.2%). Herd turnover rates were not associated with stall surface; however, the percentage of removals due to voluntary (low milk production, disposition, and dairy) and involuntary (death, illness, injury, and reproductive) reasons was different between deep-bedded and mattress-based freestalls. Voluntary removals averaged 16% of all herd removals in deep-bedded herds, whereas in mattress herds, these removals were 8%. Other welfare measurements such as cow hygiene, mortality rate, mastitis incidence, and milk production were not associated with stall surface.

  8. Frequency of traumatic cow injuries in relation to housing systems in Swiss organic dairy herds.

    PubMed

    Busato, A; Trachsel, P; Blum, J W

    2000-05-01

    A study was performed to estimate the extent of cow injuries as an indicator of animal welfare in organic dairy farms in Switzerland. The study was conducted during the winter feeding period of 1997/98 and was part of a larger project on animal health, nutrition and production in certified organic dairy herds in Switzerland. Potential predictors of injuries related to animal housing were quantified and relations between occurrence of injuries and nutritional status and production were evaluated. The investigation was designed as a cross-sectional study and included a representative sample of 152 farms and 1856 cows. Every farm was visited once and each cow was scored for claw-, skin- and joint-lesions and body condition. Statistical analyses were performed appropriate for a stratified and one-stage cluster sample weighted for the entire population of organic dairy farms in Switzerland. Possible individual and environmental predictors of cow injuries were analysed using multinomial logit models for ordinal outcomes. The overall frequencies of injuries were 10.4% for joint lesions, 12.8% for soft-tissue injuries and 3.6% for claw lesions. Most joint injuries (84.9%) were observed at the hock joint, 9.4% at the carpus and 3.1% at the knee joint. The analysis of the association between frequency of injuries and potential predictors revealed heterogeneous results and the risk profiles were different between the categories of injuries measured in the study. These observations support the assumption that variations in type and severity of injuries are due to specific differences of animal management, housing design and due to different characteristics of individual cows.

  9. 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

    2008-10-01

    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.

  10. 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

  11. A retrospective survey of the prevalence of complex vertebral malformation carriers in 9 Holstein dairy herds in Hokkaido, Japan.

    PubMed

    Nagahata, Hajime; Nishiyama, Tetsu; Kanae, Yutaka; Higuchi, Hidetoshi; Kawai, Kazuhiro; Endoh, Daiji; Hayashi, Masanobu; Kurosawa, Takashi

    2009-06-01

    The carrier rates of Complex Vertebral Malformation (CVM) in 9 Holstein dairy herds in Hokkaido, number of usages of CVM carrier semen for breeding and gene frequencies of CVM carriers were measured. The mean CVM carrier rates of 140 cows from 4 herds in 1994 and 315 cows from 5 herds in 2003 were 10.8%(range 4.7-30.0%) and 5.1%(range 0.0-6.1%), respectively. The rate of use of CVM carrier semen in the Hokkaido district was 5.6% in 2002. The gene frequencies calculated from CVM carriers among the 315 cows and number of CVM carrier semen samples used were 0.032 and 0.028, and the occurrence of homozygous CVM in 2003 was estimated to be 0.1% in the local districts of Hokkaido, Japan.

  12. Reduced likelihood of bovine coronavirus and bovine respiratory syncytial virus infection on organic compared to conventional dairy farms.

    PubMed

    Bidokhti, Mehdi R M; Tråvén, Madeleine; Fall, Nils; Emanuelson, Ulf; Alenius, Stefan

    2009-12-01

    The prevalence of antibodies to bovine coronavirus (BCV) and bovine respiratory syncytial virus (BRSV) infections was studied in 20 conventional and 20 organic dairy herds. The organic farms had produced 'certified' milk for at least 2 years. On two occasions, with a 1-year interval, 699 serum samples from 624 peri-parturient cows were tested by ELISA for antibodies to BCV and BRSV. Accompanying data relating to the sampled animals were collected in order to identify potential factors associated with increased antibody prevalence. The antibody prevalence was high at both sampling times with approximately 85% and 80% of animals positive for antibodies to BCV and to BRSV, respectively. Conventional herds had a significantly higher mean antibody prevalence to BCV and BRSV than the organically managed herds (P<0.01). Animal age was significantly associated with increased antibody prevalence (P<0.001). The findings of this study suggest that organic farm management may be effective in reducing the seroprevalence of these viruses relative to conventional farming methods.

  13. 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.

  14. Association of herd management factors with colonization of dairy cattle by Shiga toxin-positive Escherichia coli O157.

    PubMed

    Herriott, D E; Hancock, D D; Ebel, E D; Carpenter, L V; Rice, D H; Besser, T E

    1998-07-01

    Management factors in 36 Pacific Northwest dairy herds were evaluated for their association with the prevalence of Shiga toxin-positive Escherichia coli O157 (E. coli O157) in dairy cattle. The within-herd prevalence of E. coli O157 was estimated by bacteriological culture of fecal pat samples, collected monthly for 6 months (approximately 60 per visit), from heifer cattle. During the first visit to each farm, a management questionnaire was administered that covered a broad range of animal husbandry practices. On each subsequent visit, a brief questionnaire was administered to detect changes in management practices. A significantly higher prevalence of E. coli O157 was noted in herds that fed corn silage to heifers compared to herds that did not feed corn silage. More tentative associations of E. coli O157 prevalence were observed for weaning method, protein level of calf starter, feeding of ionophores in heifer rations, feeding of grain screens to heifers, and feeding of animal by-products to cows.

  15. A case-based learning approach for teaching undergraduate veterinary students about dairy herd health consultancy issues.

    PubMed

    Malher, Xavier; Bareille, Nathalie; Noordhuizen, Jos P T M; Seegers, Henri

    2009-01-01

    A case-based learning (CBL) format was implemented at the Veterinary School of Nantes, France, for veterinary students in their last year of the curriculum who had chosen to track toward a farm animal career. The focus of the CBL format was learning about dairy herd health consultancy. The goal was to emphasize teamwork among students, introduce professional communications and advisory relationships with clients, and work within the technical and economic limitations of participating farms. These farms volunteered to participate and had identified a problem. The learning objectives included gaining basic knowledge of herd-level diseases and the methods to control these within herds. The program focused on health audits of dairy farms performed by teams of four to five students, culminating in submission of a herd health management action plan specific for the farm visited by each team. The CBL program was comprised of defined learning objectives for each team. The learning process was supervised, from orientation through to validation, by a panel of experts from within the veterinary school and from local industry. Teams submitted written reports that listed recommendations and an action plan for implementation. This report was defended by each team in front of the farmers, their professional partners, and the panel of supervisors. Assessment of the program by students, participating farms, and industry professionals was positive.

  16. Risk factors for clinical mastitis, ketosis, and pneumonia in dairy cattle on organic and small conventional farms in the United States.

    PubMed

    Richert, R M; Cicconi, K M; Gamroth, M J; Schukken, Y H; Stiglbauer, K E; Ruegg, P L

    2013-07-01

    The US regulations for production of organic milk include a strict prohibition against the use of antimicrobials and other synthetic substances. The effect of these regulations on dairy animal health has not been previously reported. The objective of this study was to characterize disease detection and identify risk factors for selected diseases on organic (ORG) and similarly sized conventional (CON) farms. Dairy herds (n=292) were enrolled across 3 states (New York, Oregon, Wisconsin) with CON herds matched to ORG herds based on location and herd size. During a single herd visit, information was collected about herd management practices and animal disease occurring in the previous 60 d, and paperwork was left for recording disease occurrences during 60 d after the visit. For analysis, CON herds were further divided into grazing and nongrazing. Poisson regression models were used to assess risk factors for rate of farmer-identified and recorded cases of clinical mastitis, ketosis, and pneumonia. An increased rate of farmer-identified and recorded cases of clinical mastitis was associated with use of CON management, use of forestripping, presence of contagious pathogens in the bulk tank culture, proactive detection of mastitis in postpartum cows, and stall barn housing. An increased rate of farmer-identified and recorded cases of ketosis was associated with having a more sensitive definition of ketosis, using stall barn housing, and feeding a greater amount of concentrates. An increased rate of farmer-identified and recorded cases of pneumonia was associated with a lack of grazing, small or medium herd size, and Jersey as the predominant breed. Overall, disease definitions and perceptions were similar among grazing systems and were associated with the rate of farmer-identified and recorded cases of disease.

  17. 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

  18. 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

  19. Investigation of the vitamins A and E and beta-carotene content in milk from UK organic and conventional dairy farms.

    PubMed

    Ellis, Kathryn A; Monteiro, Ana; Innocent, Giles T; Grove-White, Dai; Cripps, Peter; McLean, W Graham; Howard, C Vyvyan; Mihm, Monika

    2007-11-01

    During a 12-month longitudinal study, bulk-tank milk was collected from organic (n=17) and conventional (n=19) dairy farms in the UK. Milk samples were analysed for vitamin A (retinol), vitamin E (alpha-tocopherol) and beta-carotene content. The farming system type, herd production level and nutritional factors affecting the milk fat vitamin content were investigated by use of mixed model analyses. Conventionally produced milk fat had a higher mean content of vitamin A than organically produced milk fat, although there were no significant differences in the vitamin E or beta-carotene contents between the two types of milk fat. Apart from farming system, other key factors that affected milk fat vitamin content were season, herd yield and concentrate feeding level. Milk vitamin content increased in the summer months and in association with increased concentrate feeding, whilst higher-yielding herds had a lower milk vitamin E and beta-carotene content. Thus, conventional dairy farms in the UK produced milk with a higher vitamin A content, possibly owing to increased vitamin A supplementation in concentrate feeds. However, knowledge of the effects of season, access to fresh grazing or specific silage types and herd production level may also be used by all producers and processors to enhance the vitamin content in milk.

  20. 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.

  1. Ranking experts' preferences regarding measures and methods of assessment of welfare in dairy herds using Adaptive Conjoint Analysis.

    PubMed

    Lievaart, J J; Noordhuizen, J P T M

    2011-07-01

    Welfare in dairy herds can be addressed using different concepts. The difficulty is to extract which measures are the most important to practically address welfare at the herd level and the methods to assess traits considered most important. Therefore, the preferences of 24 acknowledged European welfare experts were ranked regarding 70 measures suitable to assess dairy cattle welfare at herd level using the Adaptive Conjoint Analysis (ACA; Sawtooth Software, Inc., Sequim, WA) technique. The experts were selected on the basis of 3 criteria: at least 5 yr experience in animal welfare research; recent scientific publications in the field of animal welfare; and, at the most, 3 animal species including dairy cattle as their field of expertise. The 70 traits were ranked by using the median ACA questionnaire utility scores and the range between the answers of the 24 experts. A high utility score with a low range between the answers of the experts was considered as suitable to assess welfare at farm level. Measures meeting these criteria were prevalence of lameness cases (107.3±11.7), competition for feed and water (96.4±13.9), and number of freestalls per 10 cows (84.8±13.3). Based on the utility score alone, these former measures were replaced by stereotypic behavior (111.7±17.1), prevalence of lameness cases (107.3±11.7), body condition score (108.0±18.9), and hock lesions (104.7±16.1). Subsequently, to demonstrate that the ACA technique can be used to rank either well-known or inconclusive methods of assessment, the methods for the traits lameness cases and the hygiene of the calving pen were ranked using another 2 ACA questionnaires. The results are based on the opinions of selected, internationally acknowledged dairy cattle welfare experts within the European Union. In the future, other parties like dairy farmers and farmers' organization should be included to achieve consensus about the most suitable traits applicable in practice. The currently investigated

  2. Evaluation of an O antigen enzyme-linked immunosorbent assay for screening of milk samples for Salmonella dublin infection in dairy herds.

    PubMed Central

    Hoorfar, J; Lind, P; Bitsch, V

    1995-01-01

    Levels of antibodies to the O antigens (O:1,9,12) of Salmonella dublin were tested in 1355 serum, 1143 cow milk and 160 bulk milk samples from dairy herds using an enzyme-linked immunosorbent assay (ELISA). In order to define the background reaction, milk samples from all lactating cows and serum samples from 9 animals were collected in each of 20 salmonellosis-free herds located on the island of Bornholm, where cattle salmonellosis has not been reported. Similar samples were collected from all stalled animals in 10 herds with recent (< 6 months) outbreaks of salmonellosis located in Jutland, where salmonella infection is enzootic. Using herd history of salmonellosis, herd location and clinical status of the herds as criteria, the optimal cutoff in the milk ELISA was determined as being at least 5% of the samples having optical density > 0.5, resulting in herd sensitivity of 1.0 and herd specificity of 0.95. While none of the sera in the herds from Bornholm was ELISA positive, 2 herds had a few reactors in the milk ELISA. Using the same cutoff, all but 1 bulk milk sample from 150 herds on Bornholm was ELISA-negative, and all 10 salmonellosis-positive herds from Jutland were ELISA-positive. A significant correlation was found between ELISA reactions in milk and in serum of cows (34% and 32% respectively, rs = 0.69, P < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7648527

  3. The role of houseflies (Musca domestica) in harbouring Corynebacterium pseudotuberculosis in dairy herds in Israel.

    PubMed

    Braverman, Y; Chizov-Ginzburg, A; Saran, A; Winkler, M

    1999-12-01

    A study was conducted to assess the role of houseflies, Musca domestica L. in harbouring Corynebacterium pseudotuberculosis in dairy farms in Israel. The bacterium was isolated in June 1993 from 40 wild houseflies which had fed on a lesion on a cow, and from 28 laboratory flies fed on contaminated milk from a cow infected with mastitis. The bacterium was recovered from the body surface of 10 flies (of a total of 160) 10 min after being dipped entirely in a bacterial broth. The bacterium was recovered from the body surface of 10 flies (of a total of 40) 5 min after being fed on contaminated milk. When 110 flies were fed on contaminated sugar cubes, the bacterium was recovered externally from 70 flies 5 min later, and from an additional 20 flies 10 min after feeding. Of 110 flies, 80 excreted bacteria in saliva from 5 min to 3 h after feeding on contaminated milk. Bacteria were isolated from the intestine of 40 of 60 flies between 1 h and 4 h after feeding on contaminated milk. Bacteria were found in the faeces of 30 of 60 flies, between 1 h and 4 h after feeding on contaminated milk. In the light of these findings, and given the fact that this species of fly has a predilection to feed on milk residues of cow teats, the authors concluded that the housefly plays an important role in harbouring and disseminating C. pseudotuberculosis in dairy herds in Israel. In contrast, stable flies (Stomoxys calcitrans L.) are not important in the habouring and dissemination of the bacteria, since bacteria were not recovered 5, 10, 15, 30 min, 2 h or 24 h after membrane feeding on a mixture of bacterial broth and blood.

  4. A HACCP-based approach to mastitis control in dairy herds. Part 2: Implementation and evaluation

    PubMed Central

    2011-01-01

    Part 1 of the study described the development of a Hazard Analysis and Critical Control Point (HACCP) based programme and accompanying handbook for the control of mastitis. This paper describes the implementation and evaluation of customised HACCP-based programmes, which were developed from the handbook and assessed on six Irish dairy farms. Both quantitative and qualitative (action research) research methodologies were used to measure the success of implementation and efficacy of control of sub-clinical mastitis as measured by Somatic Cell Counts (SCC) and the degree of compliance by farmers in adopting and maintaining recommendations throughout the course of the study period. No overall differences in SCC before and during the implementation of the study were found when all six farms were considered together. Three of the six study farms experienced a significant decrease in herd milk recorded SCC during the implementation of the control programme. An essential part of the study was achieving initial agreement on recommendations as well as ongoing monitoring of compliance during the study. This pilot study shows that HACCP can be implemented on farms as a means of working towards the control of mastitis and that farmer attitude, and understanding of mastitis are crucial in terms of motivation irrespective of practical approaches used to manage mastitis. PMID:21777494

  5. Helicobacteraceae in Bulk Tank Milk of Dairy Herds from Northern Italy

    PubMed Central

    Bianchini, Valentina; Recordati, Camilla; Borella, Laura; Gualdi, Valentina; Scanziani, Eugenio; Selvatico, Elisa; Luini, Mario

    2015-01-01

    Helicobacter pylori is responsible for gastritis and gastric adenocarcinoma in humans, but the routes of transmission of this bacterium have not been clearly defined. Few studies led to supposing that H. pylori could be transmitted through raw milk, and no one investigated the presence of other Helicobacteraceae in milk. In the current work, the presence of Helicobacteraceae was investigated in the bulk tank milk of dairy cattle herds located in northern Italy both by direct plating onto H. pylori selective medium and by screening PCR for Helicobacteraceae, followed by specific PCRs for H. pylori, Wolinella spp., and “Candidatus Helicobacter bovis.” Three out of 163 bulk milk samples tested positive for Helicobacteraceae, but not for the subsequent PCRs. H. pylori was not isolated in any case. However, given similar growth conditions, Arcobacter butzleri, A. cryaerophilus, and A. skirrowii were recovered. In conclusion, the prevalence of Helicobacteraceae in raw milk was negligible (1.8%), and H. pylori was not identified in any of the positive samples, suggesting that, at least in the farming conditions of the investigated area, bovine milk does not represent a potential source of infection. PMID:26090429

  6. 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.

  7. Microbiological quality of bulk tank raw milk in Prince Edward Island dairy herds.

    PubMed

    Elmoslemany, A M; Keefe, G P; Dohoo, I R; Dingwell, R T

    2009-09-01

    The objectives of this study were to evaluate microbiological quality of bulk tank milk in Prince Edward Island, to evaluate correlation among milk quality criteria, and to determine seasonal effects on milk quality parameters. Bulk tank raw milk quality was evaluated on all Prince Edward Island dairy herds (n = 235) over a 2-yr period (March 2005 to March 2007). Biweekly total aerobic (TAC), preliminary incubation (PIC), laboratory pasteurization, and coliform (CC) counts were determined using a Petrifilm culture system. Additionally, bulk tank somatic cell count was determined weekly. The mean and median values were 12.8 x 10(3) and 4.9 x 10(3) cfu/mL for TAC, 29.6 x 10(3) and 13 x 10(3) cfu/mL for PIC, 87 and 12 cfu/mL for laboratory pasteurization count, 21 and 5 cfu/mL for CC, and 218 x 10(3) and 187 x 10(3) cells/mL for somatic cell count. There was moderate correlation (0.57) between TAC and PIC. All other correlation coefficients were low (<0.26). Correlation results suggest that a single quality parameter could not predict others used in this study. Seasonal data indicate that 1) in general, all counts tended to be low in winter, 2) the CC and somatic cell count were always high in summer, and 3) TAC tended to be high during summer.

  8. Risk factors associated with bulk tank standard plate count, bulk tank coliform count, and the presence of Staphylococcus aureus on organic and conventional dairy farms in the United States.

    PubMed

    Cicconi-Hogan, K M; Gamroth, M; Richert, R; Ruegg, P L; Stiglbauer, K E; Schukken, Y H

    2013-01-01

    The purpose of this study was to assess the association of bulk tank milk standard plate counts, bulk tank coliform counts (CC), and the presence of Staphylococcus aureus in bulk tank milk with various management and farm characteristics on organic and conventional dairy farms throughout New York, Wisconsin, and Oregon. Data from size-matched organic farms (n=192), conventional nongrazing farms (n=64), and conventional grazing farms (n=36) were collected at a single visit for each farm. Of the 292 farms visited, 290 bulk tank milk samples were collected. Statistical models were created using data from all herds in the study, as well as exclusively for the organic subset of herds. Because of incomplete data, 267 of 290 herds were analyzed for total herd modeling, and 173 of 190 organic herds were analyzed for the organic herd modeling. Overall, more bulk tanks from organic farms had Staph. aureus cultured from them (62% of organic herds, 42% conventional nongrazing herds, and 43% of conventional grazing herds), whereas fewer organic herds had a high CC, defined as ≥50 cfu/mL, than conventional farms in the study. A high standard plate count (×1,000 cfu/mL) was associated with decreased body condition score of adult cows and decreased milk production in both models. Several variables were significant only in the model created using all herds or only in organic herds. The presence of Staph. aureus in the bulk tank milk was associated with fewer people treating mastitis, increased age of housing, and a higher percentage of cows with 3 or fewer teats in both the organic and total herd models. The Staph. aureus total herd model also showed a relationship with fewer first-lactation animals, higher hock scores, and less use of automatic takeoffs at milking. High bulk tank CC was related to feeding a total mixed ration and using natural service in nonlactating heifers in both models. Overall, attentive management and use of outside resources were useful with regard to CC

  9. Capability index--a statistical process control tool to aid in udder health control in dairy herds.

    PubMed

    Niza-Ribeiro, J; Noordhuizen, J P T M; Menezes, J C

    2004-08-01

    Bulk milk somatic cell count (BMSCC) averages have been used to evaluate udder health both at the individual or the herd level as well as milk quality and hygiene. The authors show that the BMSCC average is not the best tool to be used in udder health control programs and that it can be replaced with advantage by the capability index (Cpk). The Cpk is a statistical process control tool traditionally used by engineers to validate, monitor, and predict the expected behavior of processes or machines. The BMSCC data of 13 consecutive months of production from 414 dairy herds as well as SCC from all cows in the DHI program from 264 herds in the same period were collected. The Cpk and the annual BMSCC average (AAVG) of all the herds were calculated. Confronting the herd's performance explained by the Cpk and AAVG with the European Union (EU) official limit for BMSCC of 400,000 cells/mL, it was noticed that the Cpk accurately classified the compliance of the 414 farms, whereas the AAVG misclassified 166 (40%) of the 414 selected farms. The annual prevalence of subclinical mastitis (SMP) of each herd was calculated with individual SCC data from the same 13-mo period. Cows with more than 200,000 SCC/mL were considered as having subclinical mastitis. A logistic regression model to relate the Cpk and the herd's subclinical mastitis prevalence was calculated. The model is: SMPe = 0.475 e(-0.5286 x Cpk). The validation of the model was carried out evaluating the relation between the observed SMP and the predicted SMPe, in terms of the linear correlation coefficient (R2) and the mean difference between SMP and SMPe (i.e., mean square error of prediction). The validation suggests that our model can be used to estimate the herd's SMP with the herd's Cpk. The Cpk equation relates the herd's BMSCC with the EU official SCC limit, thus the logistic regression model enables the adoption of critical limits for subclinical mastitis, taking into consideration the legal standard for SCC.

  10. Solution and solid state P-31 NMR characterization of phosphorus in organic and conventional dairy manure

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In the northeastern U.S., organic dairy production has increased rapidly in recent years, as Maine, Vermont, Pennsylvania and New York all rank in the top six U.S. states for the number of cows on organic dairy farms. Organic dairy farms have significant differences from conventional counterparts, i...

  11. 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

  12. Bulk tank milk somatic cell counts in dairy herds with different bovine viral diarrhoea virus status in Poland.

    PubMed

    Rola, Jolanta G; Larska, Magdalena; Grzeszuk, Monika; Bocian, Lukasz; Kuta, Aleksandra; Polak, Miroslaw P; Rola, Jerzy

    2014-09-01

    The aim of the study was to examine the effect of bovine viral diarrhoea virus (BVDV) infection on bulk tank milk somatic cell counts (BMSCC). Twenty nine dairy farms supplying milk to a dairy in Eastern Poland were recruited for the study. Bulk milk ELISA and RT-PCR were used to determine the BVDV infection status and the presence of PI animals in the farms. The BMSCC mean values for the BVDV seronegative (218.7 × 10(3)cells/ml; SD: 89.8) and seropositive (214.9 × 10(3)cells/ml; SD: 74.0) herds did not differ significantly. To assess the relationship between BVDV infection and BMSCC a multilevel mixed-effects linear model was used. No statistically significant effect of BVDV infection on BMSCC was found. The mean values of BMSCC for the herds with PI individuals measured before (230.1 × 10(3)cells/ml, SD: 64.9) and after (223.3 × 10(3)cells/ml, SD: 62.4) the PI removal were not statistically different. An increase in herd size was associated with a significant decrease in BMSCC. An increase in BMSCC was observed during summer (from May to September) compared to during winter (from October to April).

  13. Sero-epidemiological analysis of vertical transmission relative risk of Borna disease virus infection in dairy herds

    PubMed Central

    ANDO, Tatsuya; TAKINO, Tadashi; MAKITA, Kohei; TAJIMA, Motoshi; KOIWA, Masateru; HAGIWARA, Katsuro

    2016-01-01

    Borna disease virus (BDV) is a virus that causes a neurological disease in domestic animals, including a variety of animal species in Japan. Few studies have examined the mode of transmission of this virus in cattle, and the exact mechanisms underlying the transmission of the virus need to be elucidated. This study aimed to examine the contribution of vertical transmission of the virus, which occurs when the virus is transmitted from the mother to offspring during gestation or birth. We used an epidemiological approach. The relative risk (RR) was calculated for cattle born to BDV sero-positive cows from farms with a higher within-herd prevalence of BDV (56.8%). We tested the sera of 1,122 dairy cattle from 24 dairy herds in Hokkaido Prefecture, Japan, for BDV infection using the ELISA and western blotting method. The overall level of BDV sero-prevalence was 22.1%. Seroprevalence was significantly higher in closed-breeding herds that do not have buying in cows (39.7%) than in farms that restock cattle by buying in cows (4.4%, P<0.01). The overall RR of BDV vertical transmission from infected mothers to their daughters was 1.86 (95% confidence interval (CI): 1.54–2.56). Our results show that vertical transmission contributes significantly to BDV transmission in the farms tested in this study. PMID:27498995

  14. Adoption and consistency of application of premilking preparation in Ontario dairy herds.

    PubMed

    Belage, E; Dufour, S; Shock, D A; Jones-Bitton, A; Kelton, D F

    2017-03-02

    Milking management practices that affect udder health have been widely studied, leading to a variety of evidence-based recommendations. Lack of adoption or inconsistency in milking practices can interfere with efforts to prevent mastitis in the herd. The study objective was to assess the variation in adoption and application consistency of important milk harvest practices between and within farms over time. During the summer of 2013, 50 herds in southern Ontario were visited twice within a month, at milking time, and a single person observed and time-recorded premilking preparation procedures. A generalized mixed model was used to partition the variance for predisinfectant contact time and preparation lag time (time between the first contact with the teats and cluster attachment), and determine the proportion of variation attributable to farms, milkers, visits, and characteristics of a cow milking. Using logistic regression, models were built to assess factors affecting adequate contact time and adequate preparation lag time, respectively. Farm, the person(s) milking, and visit number were used as random effects in both instances. In both models, farm-to-farm differences and variations between cows during a specific milking accounted for the largest part of the variability seen in both contact time (47 and 44%, respectively) and preparation lag time (40 and 36%, respectively). For both outcomes, milkers were consistent in their routines over the 2 visits (only 9 and 3.1% of total variance for contact and preparation lag time, respectively). Parlors were more likely to meet the recommended contact time than tie-stalls; increased number of milkers at milking time and having contact times under 30 s had negative effects on meeting recommended preparation lag time. The majority of farms in the study complied with the recommendations for adequate milking practices; however, most did not follow a consistent timed protocol. There are several potential sources of variation

  15. Associations between herd-level factors and lying behavior of freestall-housed dairy cows.

    PubMed

    Ito, K; Chapinal, N; Weary, D M; von Keyserlingk, M A G

    2014-01-01

    Our objective was to investigate the associations between herd-level factors and lying behavior of high-producing dairy cows housed in freestall barns. Lying behavior of approximately 40 focal cows in one high-producing pen was monitored on each of 40 farms in the northeastern United States (NE) and 39 farms in California (CA). All cows within the pen were gait scored using a 1-to-5 scale to calculate the prevalence of clinical lameness (score ≥3) and severe lameness (score ≥4). Facility and management measures, including stall design, bedding, and flooring type within the pen, were collected. Herd-level factors associated with daily lying time, standard deviation (SD) of daily lying time, frequency of lying bouts, and lying bout duration at the univariate level were submitted to multivariable general linear models. In the NE, daily lying time increased with the use of deep bedding (estimate = 0.80±0.31h/d) and as average days in milk (DIM) of the focal cows increased (estimate = 0.08±0.04h/d for a 10-d increase in DIM). The SD of daily lying time decreased as stall stocking density increased (estimate = -0.08±0.03h/d for a 10% increase), and increased with the presence of rubber flooring in the pen (estimate = 0.16±0.08h/d) and percentage of stalls with fecal contamination (estimate = 0.04±0.01h/d for a 10% increase). Frequency of lying bouts decreased (estimate = -1.90±0.63 bouts/d) and average bout duration increased (estimate = 15.44±3.02 min) with the use of deep bedding. In CA, where all farms used deep bedding, daily lying time increased as average DIM of the focal cows increased (estimate = 0.08±0.03h/d for a 10-d increase). The SD of daily lying time decreased when feed was delivered more than once per day (estimate = -0.24±0.08h/d). The percentage of lame cows was correlated with the percentage of stalls with fecal contamination (r=0.45), which in turn was associated with fewer (estimate = -0.25±0.06 bouts/d) and longer lying bouts (estimate

  16. 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

  17. Associations between herd-level feeding management practices, feed sorting, and milk production in freestall dairy farms.

    PubMed

    Sova, A D; LeBlanc, S J; McBride, B W; DeVries, T J

    2013-07-01

    The challenges associated with group-housed dairy cows include within-herd variability in nutrient consumption and milk production, which may be related to feeding management. The objective of this observational study was to examine the association of herd-level feeding management factors, feed sorting, and milk production. Twenty-two freestall herds with an average lactating herd size of 162±118 cows, feeding total mixed rations, were each studied for 7 consecutive days in summer and winter. In cases of multiple feeding groups within a herd, the highest producing group of cows with an even distribution of days in milk and parity was selected for this study. The average group size studied was 83±31 cows. The average study group consisted of cows 187±47 days in milk, with a parity of 2.3±0.6, consuming 24.3±2.6kg of dry matter, with an average group-level yield of 34.3±6kg of milk/d, 3.7±0.3% milk fat, and 3.2±0.18% milk protein. Milk production parameters, including yield, fat, and protein, were recorded through regular Dairy Herd Improvement milk testing. A survey of feeding management practices and barn characteristics was administered on each farm. The amounts of feed offered and refused were recorded and sampled daily to assess dry matter intake (DMI) and particle size distribution. Feeding twice per day compared with once per day was associated with an average increase of 1.42kg of DMI, 2.0kg of milk yield, and less sorting against long ration particles (>19mm). Every 2% group-level selective refusal (sorting) of long particles was associated with 1kg/d of reduction in milk yield. A 10cm/cow increase in feed bunk space was associated with a 0.06-percentage-point increase in group-average milk fat and a 13% decrease in group-average somatic cell count. These results support that herd-level management practices to promote feed access, such as increased feeding frequency and bunk space, may improve DMI and promote more balanced nutrient intake and greater

  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. A scoring system for risk assessment of the introduction and spread of bovine viral diarrhoea virus in dairy herds in Northern Italy.

    PubMed

    Luzzago, Camilla; Frigerio, Michela; Piccinini, Renata; Daprà, Valentina; Zecconi, Alfonso

    2008-08-01

    To support a voluntary disease control program, this study aimed to develop an integrated scoring system for the risk assessment of bovine viral diarrhoea virus (BVDV) infection in dairy herds in Northern Italy. Sixty-two dairy herds were classified according to their BVDV serological status. Farmers were interviewed using a questionnaire on potential BVDV risk factors. Scores were used to define risk levels for factors related to (1) BVDV introduction (through livestock trade, attendance of animals at shows/exhibitions and grazing common pasture), (2) within-herd spread of BVDV and (3) the results of initial serological testing. The calculated odds ratios were significant for all categories, except for livestock trade. The application of the screening test, the questionnaire and the related risk assessment showed this to be a practical approach to predicting BVDV herd status.

  20. Dynamics of culling for Jersey, Holstein, and Jersey × Holstein crossbred cows in large multibreed dairy herds.

    PubMed

    Pinedo, P J; Daniels, A; Shumaker, J; De Vries, A

    2014-05-01

    The objective of this observational study was to describe and compare the dynamics of reason-specific culling risk for the genetic groups Jerseys (JE), Holsteins (HO), and Jersey × Holstein crossbreds (JH), considering parity, stage of lactation, and milk yield, among other variables, in large multibreed dairy herds in Texas. The secondary objective was to analyze the association between survival and management factors, such as breeding and replacement policies, type of facilities, and use of cooling systems. After edits, available data included 202,384 lactations in 16 herds, ranging from 407 to 8,773 cows calving per year during the study period from 2007 to 2011. The distribution of lactation records by genetic group was 58, 36, and 6% for HO, JE, and JH crosses, respectively. Overall culling rates across breeds were 30.1, 32.1, and 35.0% for JH, JE, and HO, respectively. The dynamics of reason-specific culling were dependent on genetic group, parity, stage of lactation, milk yield, and herd characteristics. Early lactation was a critical period for "died" and "injury-sick" culling. The risk increased with days after calving for "breeding" and, in the case of HO, "low production" culling. Open cows had a 3.5 to 4.6 times greater risk for overall culling compared with pregnant cows. The odds of culling with reason "died" within the first 60 d in milk (DIM) were not significantly associated with genetic group. However, both JE and JH crosses had lower odds of live culling within the first 60 DIM compared with HO cows (OR=0.72 and 0.82, respectively). Other cow variables significantly associated with the risk of dying within the first 60 DIM were cow relative 305-d mature equivalent (305ME) milk yield, parity, and season of calving. Significant herd-related variables for death included herd size and origin of replacements. In addition to genetic group, the risk of live culling within 60 DIM was associated with cow-relative 305ME milk yield, parity, and season of

  1. Data quality in the Norwegian dairy herd recording system: agreement between the national database and disease recording on farm.

    PubMed

    Espetvedt, M N; Reksen, O; Rintakoski, S; Osterås, O

    2013-04-01

    The majority of herds in Norway participate in the national dairy herd recording system. For disease events, this involves transferring information registered on farm, using individual cow health cards (CHC), to the central cattle database (CCD). Before using data from such a database, validation with an aim of describing data quality should be performed, but is rarely done. In this study, diagnostic events from CHC and CCD from 74 dairy herds were compared. Events in 2008 from female cattle with minimum age of 1 yr were included (n=1,738). Discrepancies between the 2 data sources and assessment of data quality were evaluated using agreement between events on CHC and in CCD, calculating completeness and correctness for the CCD, and using a multivariable regression model for agreement (1/0). The agreement evaluation described the concordance between the 2 data sources, whereas the calculations of completeness and correctness depended on a reference data source assumed to be more reliable. Completeness of the CCD was defined as the proportion of diagnostic events on the CHC that was recorded therein. Correctness was defined as the proportion of the CCD events that was also recorded on the CHC, and with the same date and diagnostic code. The agreement was up to 87.5%, the majority of disagreement being caused by unreported events on the CHC (between 10 and 12% of all events). Completeness of the CCD was regarded as high, between 0.87 and 0.88, and correctness excellent, between 0.97 and 0.98. The multivariable regression model found 4 factors that increased the odds for diagnostic events being in agreement between CHC and CCD. These were the events occurring during the 305-d lactation period; the herd size being 75 cows or less; the event occurring during the spring, summer, or winter rather than autumn; and lastly, the diagnostic code for the disease event being preprinted on the CHC, involving a simple check mark as opposed to writing a 3-digit code. The model found

  2. 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).

  3. Effects of feeding practices on milk yield and composition in peri-urban and rural smallholder dairy cow and pastoral camel herds in Kenya.

    PubMed

    Kashongwe, O B; Bebe, B O; Matofari, J W; Huelsebusch, C G

    2017-03-29

    Associations between feeding practices, milk yield, and composition were assessed in smallholder rural and peri-urban dairy cow (n = 97) and pastoral camel (n = 15) herds. A cross-sectional survey supplemented by follow-up collection of feed and milk samples for laboratory analyses was conducted. Data was analyzed using descriptive, correlation, and analysis of variance statistics. Feeding practices in rural smallholder dairy cows' herds were pastured based (87.7%) with napier grass (89.4%) and concentrates (93.9%) as forage and concentrate supplements. In smallholder peri-urban dairy cows' herds, it was napier grass based (68.4%) with concentrates (100%), oat forages (42.9%), and crop residues (28.6%). Pastoral camel herds were shrub browsing (53%), rangeland pasture grazing (20%), or Euphorbia tirucalli feeding (27%). Smallholder rural farmers offered more feeds (16.1 vs 15.3 kg/day) than peri-urban farmers, hence net energy for lactation (1.4 vs 1.3 Mcal/kg), crude protein (CP) (10 vs 12%), and milk yields (12 vs 9 kg/herd/day) was higher. Milk fat was higher in smallholder peri-urban (4.3%) than that of rural (3.9%). In pastoral camels, E. tirucalli feeding had higher daily milk yield/herd, fat, and CP (63 kg, 4.5 and 3.6%) than shrub browsing (35 kg, 4.2 and 3.0%) and grazing (23 kg yield, 2.6 and 2.7%). Five feeding practices out of 14 in smallholder dairy cattle herds resulted in more than 10 kg milk/cow/day because of low forage-to-concentrate ratio (2.5), inclusion of legume crop residue, or processing forages. They present opportunities for improved production in smallholder herds. In pastoral camel, E. tirucalli feeding showed the highest potential.

  4. Comparison of management practices between Ohio, USA dairy farms participating in whole-herd Johne's disease testing programs and those not participating.

    PubMed

    Naugle, Alecia Larew; Saville, William J A; Shulaw, William P; Wittum, Thomas E; Love, Brenda C; Dodaro, Stephen J; McPhail, I Lee

    2004-08-30

    The purpose of our mail survey was to compare the adoption of management practices recommended for Johne's disease (JD) control between herds involved in whole-herd testing programs versus those that do not routinely test the entire herd for JD. A questionnaire consisted of 38 closed-ended questions that inquired about: general herd characteristics; management practices related to JD control; changes that occurred within the last 5 years regarding management practices recommended for the control of JD; producer knowledge of JD; the perceived infection status of the herd by the producer; and herd JD-testing history. The questionnaire was mailed to 810 Ohio dairy producers in September 2002; 266 questionnaires were returned (32.8% response). We used univariable logistic-regression models to assess the relationship between whole-herd testing status (TESTING versus NON-TESTING) and each management practice, each change in management practice and producer knowledge about JD. Because it is conceivable that only producers who believe their herds to be infected would be motivated to adopt the management practices recommended for control of JD, the comparisons were repeated with models that controlled for producer-perceived infection status. Of the 20 management practices recommended for JD control that we evaluated, 7 differed between TESTING and NON-TESTING herds. Additionally, TESTING herds more-frequently reported adopting changes within the past 5 years relative to NON-TESTING herds with respect to 7 of 9 management practices evaluated. Producers with TESTING herds also reported greater familiarity with JD than those with NON-TESTING herds.

  5. Risk factors for bacteriological quality of bulk tank milk in Prince Edward Island dairy herds. Part 1: overall risk factors.

    PubMed

    Elmoslemany, A M; Keefe, G P; Dohoo, I R; Jayarao, B M

    2009-06-01

    The objective of this study was to determine on-farm risk factors for bacteriological quality of bulk tank milk. Bulk tank raw milk quality was evaluated on all Prince Edward Island dairy herds (n = 235) over a 2-yr period (March 2005 to March 2007). Biweekly total bacterial, preliminary incubation, laboratory pasteurization, and coliform counts were conducted using a Petrifilm culture system. For the assessment of risk factors, a case-control study was conducted from January 2006 to May 2007. Case and control herds were defined based on the last 6 analyses of bulk tank bacterial counts before on-farm evaluation. Cases were herds that had multiple elevated counts for any of the parameters measured. A total of 69 herds (39 cases and 30 control herds) were evaluated. Data collection included 1) observation and questionnaire on basic hygiene and farm management practices; 2) complete wash analysis of the milking equipment, monitoring the presence of bacterial films on equipment and evaluation of cooling system function; and 3) environmental and cow hygiene scoring. Data were analyzed using multivariable logistic regression. The results of the final model indicated that high alkalinity in the wash water and poor teat-end cleanliness were associated with high bacterial counts in bulk tank milk (odds ratios = 12 and 5.3, respectively). It was also observed that high water temperature of detergent wash and the use of a water softener were associated with low bacterial counts in bulk tank milk (odds ratios = 0.87 and 0.11, respectively). A significant association between udder hair clipping and teat-end cleanliness was also observed. In conclusion, this study highlights the importance of udder hygiene and milking system washing factors on hygienic quality of bulk tank milk.

  6. 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.

  7. A large Markovian linear program to optimize replacement policies and dairy herd net income for diets and nitrogen excretion.

    PubMed

    Cabrera, V E

    2010-01-01

    The purpose of the study was 2-fold: 1) to propose a novel modeling framework using Markovian linear programming to optimize dairy farmer-defined goals under different decision schemes and 2) to illustrate the model with a practical application testing diets for entire lactations. A dairy herd population was represented by cow state variables defined by parity (1 to 15), month in lactation (1 to 24), and pregnancy status (0 nonpregnant and 1 to 9 mo of pregnancy). A database of 326,000 lactations of Holsteins from AgSource Dairy Herd Improvement service (http://agsource.crinet.com/page249/DHI) was used to parameterize reproduction, mortality, and involuntary culling. The problem was set up as a Markovian linear program model containing 5,580 decision variables and 8,731 constraints. The model optimized the net revenue of the steady state dairy herd population having 2 options in each state: keeping or replacing an animal. Five diets were studied to assess economic, environmental, and herd structural outcomes. Diets varied in proportions of alfalfa silage (38 to 98% of dry matter), high-moisture ear corn (0 to 42% of dry matter), and soybean meal (0 to 18% of dry matter) within and between lactations, which determined dry matter intake, milk production, and N excretion. Diet ingredient compositions ranged from one of high concentrates to alfalfa silage only. Hence, the model identified the maximum net revenue that included the value of nutrient excretion and the cost of manure disposal associated with the optimal policy. Outcomes related to optimal solutions included the herd population structure, the replacement policy, and the amount of N excreted under each diet experiment. The problem was solved using the Excel Risk Solver Platform with the Standard LP/Quadratic Engine. Consistent replacement policies were to (1) keep pregnant cows, (2) keep primiparous cows longer than multiparous cows, and (3) decrease replacement rates when milk and feed prices are favorable

  8. Prevalence of Coxiella burnetii in bulk milk samples from dairy bovine, ovine, caprine, and camel herds in Iran as determined by polymerase chain reaction.

    PubMed

    Rahimi, Ebrahim; Ameri, Mehrdad; Karim, Guity; Doosti, Abbas

    2011-02-01

    Q fever is a widespread zoonosis caused by the obligate intracellular micro-organism Coxiella burnetii. The objective of this study was to determine the prevalence rate of C. burnetii in bulk milk samples from dairy bovine, ovine, caprine, and camel herds in Isfahan province, Iran. In the present study, 567 bulk milk samples from 186 dairy bovine, ovine, caprine, and camel herds were tested for C. burnetii using a nested polymerase chain reaction assay. The animals whose milk samples collected for this study were clinically healthy. In total, 8 of 247 (3.2%) bovine milk samples were positive; the positive samples originated from 6 of 90 (6.7%) dairy herds. Eight of 140 (5.7%) ovine bulk milk samples from 42 sheep breeding farms and 5 of 110 (4.5%) caprine bulk milk samples from 32 goat breeding farms were positive for C. burnetii. One of 70 (1.4%) camel bulk milk samples from 22 camel breeding farms was also positive for C. burnetii. Although no extensive prevalence study was undertaken, the results of this study indicate that clinically healthy dairy animals are important sources of C. burnetii infection in Iran. To the authors' knowledge, this study is the first report of direct identification of C. burnetii using polymerase chain reaction in bulk milk samples from dairy ovine herds in Iran and the first report of direct identification of C. burnetii in bulk milk samples from dairy camel herds. Further intensive prevalence studies on Coxiella infection and on possible risks of dairy products will be needed to elucidate the epidemiology of Q fever in Iran.

  9. Spread of tetracycline resistance genes at a conventional dairy farm

    PubMed Central

    Kyselková, Martina; Jirout, Jiří; Vrchotová, Naděžda; Schmitt, Heike; Elhottová, Dana

    2015-01-01

    The use of antibiotics in animal husbandry contributes to the worldwide problem of increasing antibiotic resistance in animal and human pathogens. Intensive animal production is considered an important source of antibiotic resistance genes released to the environment, while the contribution of smaller farms remains to be evaluated. Here we monitor the spread of tetracycline resistance (TC-r) genes at a middle-size conventional dairy farm, where chlortetracycline (CTC, as intrauterine suppository) is prophylactically used after each calving. Our study has shown that animals at the farm acquired the TC-r genes in their early age (1–2 weeks), likely due to colonization with TC-resistant bacteria from their mothers and/or the farm environment. The relative abundance of the TC-r genes tet(W), tet(Q), and tet(M) in fresh excrements of calves was about 1–2 orders of magnitude higher compared to heifers and dairy cows, possibly due to the presence of antibiotic residues in milk fed to calves. The occurrence and abundance of TC-r genes in fresh excrements of heifers and adult cows remained unaffected by intrauterine CTC applications, with tet(O), tet(Q), and tet(W) representing a “core TC-resistome” of the farm, and tet(A), tet(M), tet(Y), and tet(X) occurring occasionally. The genes tet(A), tet(M), tet(Y), and tet(X) were shown to be respectively harbored by Shigella, Lactobacillus and Clostridium, Acinetobacter, and Wautersiella. Soil in the farm proximity, as well as field soil to which manure from the farm was applied, was contaminated with TC-r genes occurring in the farm, and some of the TC-r genes persisted in the field over 3 months following the manure application. Concluding, our study shows that antibiotic resistance genes may be a stable part of the intestinal metagenome of cattle even if antibiotics are not used for growth stimulation, and that smaller dairy farms may also contribute to environmental pollution with antibiotic resistance genes. PMID

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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 mo...

  11. Lameness prevalence and risk factors in organic and non-organic dairy herds in the United Kingdom.

    PubMed

    Rutherford, Kenneth M D; Langford, Fritha M; Jack, Mhairi C; Sherwood, Lorna; Lawrence, Alistair B; Haskell, Marie J

    2009-04-01

    This study aimed to compare the prevalence of lameness on organic and non-organic dairy farms in the United Kingdom (UK) and to assess which cow and farm factors influenced lameness levels. Forty organic and 40 non-organic dairy farms across the UK were repeatedly visited over a 2.5 year period. On each visit all milking cows were locomotion scored, and information about farm housing, management and husbandry practices was recorded on-farm. Over the whole study, the mean herd lameness prevalence was 16.2%, 16.3% and 19.3% in the autumn, winter and spring observation periods, respectively. Lameness prevalence was lower (P=0.012) on organic farms compared to non-organic farms. Numerous specific factors were found to significantly influence the prevalence of lameness. This study provided evidence that organic management reduced herd lameness. It supported previous research which suggested that lameness is a serious problem on many farms in the UK and further emphasised the multi-factorial aetiology of lameness problems.

  12. Relationship of electric power quality to milk production of dairy herds - field study with literature review.

    PubMed

    Hillman, Donald; Stetzer, Dave; Graham, Martin; Goeke, Charles L; Mathson, Kurt E; Vanhorn, Harold H; Wilcox, Charles J

    2013-03-01

    Public Utility Commissions (PUC) in several states adopted 0.5 volt rms (root mean squared) or 1.0 milliampere as the actionable limit for utilities to respond to complaints of uncontrolled voltage. This study clearly shows that the actionable level should be reduced to 10 mV p-p (peak-to-peak), which is 140 times less than the current standard. Dairy farmer complaints that animal behavior and milk production were affected by electrical shocks below adopted standards were investigated on 12 farms in Wisconsin, Michigan, and Minnesota. Milk production per cow was determined from daily tank-weight pickup and number of cows milked. Number of transient events, transients, voltage p-p, waveform phase angle degree, sags, and sag-Vrms were measured from event recorders plugged into milk house wall outlets. Data from 1705 cows and 939 data points were analyzed by multiherd least-squares multiple regression and SAS-ANOVA statistical programs. In five herds for 517 days, milk/cow/day decreased -0.0281 kg/transient event as transient events increased from 0 to 122/day (P<0.02). Negative effects on milk/cow/day from event recorder measurements were significant for eight independent electrical variables. Step-potential voltage and frequency of earth currents were measured by oscilloscope from metal plates grouted into the floor of milking stalls. Milk decreased as number of 3rd, 5th, 7th, 21st, 28th, and 42nd harmonics and the sum of triplen harmonics (3rd, 9th, 15th, 21st, 27th, 33rd, and 39th) increased/day (P<0.003). Event recorder transient events were positively correlated with oscilloscope average V p-p event readings. Steps/min counted from videotapes of a dancing cow with no contact to metal in the barnyard were correlated with non-sinusoidal 8.1 to 14.6 mV p-p impulses recorded by oscilloscope for 5 min from EKG patches on legs. PUC standards and use of 500-Ohm resistors in test circuits underestimate effects of non-sinusoidal, higher frequency voltage/current common

  13. Variability of acetone in milk in a large low-production dairy herd: a longitudinal case study.

    PubMed

    Heuer, C; Wangler, A; Schukken, Y H; Noordhuizen, J P

    2001-05-01

    The objective of this study was to relate acetone in milk with cow and management factors in one low producing dairy herd (5260 kg milk per 305-day lactation). Milk acetone was measured in regular monthly milk samples one to three times within 100 days of lactation in 4433 lactations (2639 cows, 7800 measurements) from one herd over a period of 32 months (1988-91). Associations between milk acetone and cow factors and surrogate measures of management were evaluated by variance components of multiple fixed effect models. Lactation stage, calendar month of study, production groups and milk yield were strong, and percentage milk fat and parity were weak predictors of milk acetone. There was a trend of increasing body weight loss from the first to the second month of lactation with increasing milk acetone level. A substantial increase in milk production in 1991 was accompanied by an almost twofold rise in milk acetone. It was concluded that environmental parameters had strong relationships with milk acetone even in this low-producing herd.

  14. 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

  15. Behavior of cows during and after peak feeding time on organic and conventional dairy farms in the United Kingdom.

    PubMed

    Langford, F M; Rutherford, K M D; Sherwood, L; Jack, M C; Lawrence, A B; Haskell, M J

    2011-02-01

    The behavior of groups of housed, lactating dairy cattle was observed over 2 winter housing periods on 20 organic farms and 20 conventional farms in the United Kingdom. Three methods were used: (1) 6 video-clips of 10 min duration were captured of cows feeding at sections of the feed-bunk face during the peak feeding period (0 to 90 min) and continuously observed for aggressive interactions among cows; (2) the proportion of cows at the feed-bunk face was scanned every 15 min for 4.5h to include the peak feeding period (0 to 255 min); and (3) all nonfeeding behaviors were scanned every 15 min for 2.5h after the peak feeding period (120 to 255 min). The latter scans were analyzed post hoc for measures of cow comfort (freestall farms only). Management and health data were collected on each farm. On farms with open-fronted feed-bunk faces, a greater number of aggressive interactions occurred at the feed-bunk face at peak feeding time on organic farms than on conventional farms (organic = 36.3 ± 4.4; conventional = 29.1 ± 3.0). Higher proportions of cows were at the feed-bunk face at peak feeding on organic farms than on conventional farms (organic=0.58 ± 0.04; conventional=0.48 ± 0.03). Housing type (freestall versus straw pen) explained most differences in postfeeding behavior (proportion of ruminating cow in alleyways: freestalls=0.16±0.06 vs. straw-pen=0.08 ± 0.03), with few differences between organic and conventional herds. On freestall farms, the proportions of cows on organic farms lying down postfeeding was smaller than in conventional herds (organic=0.38 ± 0.09 vs. conventional=0.43 ± 0.07). Differences in behavior around peak feeding time could be associated with the reduction in food "quality" on organic farms compared with the energy requirement of the cows, with cows on organic farms being highly motivated to feed. A correlation was observed between farms that had high amounts of lying and farms that had high lameness prevalence (R(2

  16. Assessing the potential impact of Salmonella vaccines in an endemically infected dairy herd

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Salmonella spp. in cattle are contributing to bacterial foodborne disease for humans. Reduction of Salmonella prevalence in herds is important to prevent human Salmonella infections. Typical control measures are culling of infectious animals, vaccination, and improved hygiene management. Vaccines ha...

  17. Economic consequences of mastitis and withdrawal of milk with high somatic cell count in Swedish dairy herds.

    PubMed

    Nielsen, C; Ostergaard, S; Emanuelson, U; Andersson, H; Berglund, B; Strandberg, E

    2010-10-01

    The main aim was to assess the impact of mastitis on technical and economic results of a dairy herd under current Swedish farming conditions. The second aim was to investigate the effects obtained by withdrawing milk with high somatic cell count (SCC). A dynamic and stochastic simulation model, SimHerd, was used to study the effects of mastitis in a herd with 150 cows. Results given the initial incidence of mastitis (32 and 33 clinical and subclinical cases per 100 cow-years, respectively) were studied, together with the consequences of reducing or increasing the incidence of mastitis by 50%, modelling no clinical mastitis (CM) while keeping the incidence of subclinical mastitis (SCM) constant and vice versa. Six different strategies to withdraw milk with high SCC were compared. The decision to withdraw milk was based on herd-level information in three scenarios: withdrawal was initiated when the predicted bulk tank SCC exceeded 220 000, 200 000 or 180 000 cells/ml, and on cow-level information in three scenarios: withdrawal was initiated when the predicted SCC in an individual cow's milk exceeded 1 000 000, 750 000 or 500 000 cells/ml. The accuracy with which SCC was measured and predicted was assumed to affect the profitability of withdrawing milk with high SCC and this was investigated by applying high, low or no uncertainty to true SCC. The yearly avoidable cost of mastitis was estimated at €8235, assuming that the initial incidence of mastitis could be reduced by 50%. This cost corresponded to 5% of the herd net return given the initial incidence of mastitis. Expressed per cow-year, the avoidable cost of mastitis was €55. The costs per case of CM and SCM were estimated at €278 and €60, respectively. Withdrawing milk with high SCC was never profitable because this generated a substantial amount of milk withdrawal that was not offset by a sufficient increase in the average price per delivered kg milk. It had the most negative impact on net return when

  18. A comparison of timed artificial insemination and automated activity monitoring with hormone intervention in 3 commercial dairy herds.

    PubMed

    Dolecheck, K A; Silvia, W J; Heersche, G; Wood, C L; McQuerry, K J; Bewley, J M

    2016-02-01

    The objective of this study was to compare the reproductive performance of cows inseminated based on automated activity monitoring with hormone intervention (AAM) to cows from the same herds inseminated using only an intensive timed artificial insemination (TAI) program. Cows (n=523) from 3 commercial dairy herds participated in this study. To be considered eligible for participation, cows must have been classified with a body condition score of at least 2.50, but no more than 3.50, passed a reproductive tract examination, and experienced no incidences of clinical, recorded metabolic diseases in the current lactation. Within each herd, cows were balanced for parity and predicted milk yield, then randomly assigned to 1 of 2 treatments: TAI or AAM. Cows assigned to the TAI group were subjected to an ovulation synchronization protocol consisting of presynchronization, Ovsynch, and Resynch for up to 3 inseminations. Cows assigned to the AAM treatment were fitted with a leg-mounted accelerometer (AfiAct Pedometer Plus, Afimilk, Kibbutz Afikim, Israel) at least 10 d before the end of the herd voluntary waiting period (VWP). Cows in the AAM treatment were inseminated at times indicated by the automated alert system for up to 90 d after the VWP. If an open cow experienced no AAM alert for a 39±7-d period (beginning at the end of the VWP), hormone intervention in the form of a single injection of either PGF2α or GnRH (no TAI) was permitted as directed by the herd veterinarian. Subsequent to hormone intervention, cows were inseminated when alerted in estrus by the AAM system. Pregnancy was diagnosed by ultrasound 33 to 46 d after insemination. Pregnancy loss was determined via a second ultrasound after 60 d pregnant. Timed artificial insemination cows experienced a median 11.0 d shorter time to first service. Automated activity-monitored cows experienced a median 17.5-d shorter service interval. No treatment difference in probability of pregnancy to first AI, probability

  19. 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

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

    PubMed Central

    Garg, Rajni; Patil, Prasanna Kumar; Sharma, Shukriti; Gandham, Ravi Kumar; Singh, Ajay Vir; Filia, Gurusimiran; Singh, Pravin Kumar; Jayaraman, Sujata; Gupta, Saurabh; Chaubey, Kundan Kumar; Saminathan, Mani

    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. PMID:25945351

  1. Feeding, production, and efficiency of Holstein-Friesian, Jersey, and mixed-breed lactating dairy cows in commercial Danish herds.

    PubMed

    Kristensen, T; Jensen, C; Østergaard, S; Weisbjerg, M R; Aaes, O; Nielsen, N I

    2015-01-01

    The objective of this paper was to compare efficiency measures, milk production, and feed intake for lactating cows in commercial herds using different breeds and production and milking systems. To accomplish this, we used all feed evaluations made by the Danish extension service during the period November 2012 to April 2013 for 779 herds, of which 508 were Holstein-Friesian (HOL); 100 were Jersey (JER); and 171 herds were a mixture of these 2 breeds, other dairy breeds, and crossbreeds (OTH). The annually recorded, herd-average energy-corrected milk (ECM) yield was 8,716kg (JER) and 9,606kg (HOL); and average herd size was 197 cows (HOL) and 224 cows (JER). All cows were fed a total mixed or partial mixed ration supplemented with concentrate from feeding stations, housed in loose housing systems with a slatted floor, and milked in either a parlor milking unit or an automatic milking system. Energy efficiency was calculated as net energy efficiency defined as total energy demand as a percentage of energy intake and as residual feed intake defined as energy intake (net energy for lactation; NEL) minus energy requirement. Production efficiency was expressed as kilograms of ECM per kilogram of dry matter intake (DMI), kilograms of ECM per 10 MJ of net energy intake (NEL), kilograms of ECM per 100kg of BW, and kilograms of DMI per 100kg of BW. Environmental efficiency was expressed by the nitrogen efficiency calculated as N in milk and meat as a percentage of N in intake, and as enteric emission of methane expressed as kilograms of ECM per megajoule of CH4. Mean milk yield for lactating cows was 30.4kg of ECM in HOL and 3kg less in JER, with OTH herds in between. Mean NEL intake was 122 MJ in JER, increasing to 147 MJ in HOL, whereas ration energy density between breeds did not differ (6.4-6.5 MJ of NEL per kg of DMI). The NEL intake and DMI explained 56 and 47%, respectively, of variation in production (ECM) for HOL herds but only 44 and 27% for JER. Jersey had a

  2. Growth, carcass characteristics, and profitability of organic versus conventional dairy beef steers.

    PubMed

    Bjorklund, E A; Heins, B J; Dicostanzo, A; Chester-Jones, H

    2014-03-01

    Bull calves (n=49), born at the University of Minnesota West Central Research and Outreach Center (Morris) between March and May 2011, were used to compare growth measurements and profitability of conventional and organic dairy steers. Calves were assigned to 1 of 3 replicated groups at birth: conventional (CONV; n=16), organic (pasture and concentrate; ORG; n=16), or organic grass only (GRS; n=17), and analysis of variables was on a pen basis. Breed groups of calves were Holstein (HO; n=9); Holsteins (n=11) maintained at 1964 breed average level; crossbreds (n=19) including combinations of HO, Montbéliarde, and Swedish Red; and crossbreds (n=10) including combinations of HO, Jersey, Swedish Red, and Normande. The CONV steers were fed a diet of 80% concentrate and 20% forage. The ORG steers were fed a diet of organic corn, organic corn silage, and at least 30% of their diet consisted of organic pasture during the grazing season. The GRS steers grazed pasture during the grazing season and were fed high-quality hay or hay silage during the nongrazing season. Intakes of a total mixed ration were recorded daily with herd management software. A profit function was defined to include revenues and expenses for beef value, feed intake, pasture intake, health cost, and yardage. The GRS (358.6 kg) steers had lesser total gains from birth to slaughter than ORG (429.6 kg) and CONV (534.5 kg) steers. Furthermore, the GRS (0.61 kg/d) steers had lesser average daily gain from birth compared with ORG (0.81 kg/d) and CONV (1.1 kg/d) steers. The GRS and ORG steers had smaller rib eye area (49.5 and 65.8 cm(2), respectively) compared with CONV (75.4 cm(2)) steers. For profitability, GRS steers had 43% greater profit than CONV steers due to organic beef price premiums and lower feed costs. On the other hand, ORG steers had substantially less profit than CONV steers. The higher cost of production for the ORG steers is due to the extreme high value of organic corn. The results of the

  3. Genetic diversity of bovine papillomavirus types, including two putative new types, in teat warts from dairy cattle herds.

    PubMed

    Lunardi, Michele; de Camargo Tozato, Claudia; Alfieri, Alice Fernandes; de Alcântara, Brígida Kussumoto; Vilas-Boas, Laurival Antonio; Otonel, Rodrigo Alejandro Arellano; Headley, Selwyn Arlington; Alfieri, Amauri Alcindo

    2016-06-01

    Teat papillomatosis affects dairy cows worldwide. Milking can become difficult due to teat warts, and maintaining affected cows in the herds may diminish economic profit in the dairy industry. Currently, 13 bovine papillomavirus (BPV) types have been fully characterized, and numerous putative BPV types have been identified through partial L1 gene PCR. In order to identify the viral types present in warts on the udders of dairy cows, 40 teat lesions from 24 cows from 13 cattle farms in three States of Brazil were evaluated by PV L1 gene PCR. The warts that were evaluated contained sequences from BPVs 6-10, the putative BPV types BAPV9 and BAPV4, and two unreported putative papillomavirus (PV) types, named BPV/BR-UEL6 and BPV/BR-UEL7. In addition, mixed infections and coinfections were identified, since more than one lesion was observed on the udders of 13 cows. Phylogenetic analysis showed that BPV/BR-UEL6 is closely related to BPVs belonging to the genus Xipapillomavirus, while BPV/BR-UEL7 clustered with the previously reported strains Cervus timorensis and Pudu puda PVs, which represent a putative new PV type, and it was only distantly related to xi-, epsilon-, delta- and dyoxi-PVs. These results provide information that will assist in the understanding of the association of BPVs 6, 7, 8, 9, and 10, as well as putative BPV types BAPV4 and BAPV9, with mammary papillomatosis. This is the first characterization of putative novel PV types BPV/BR-UEL6 and BPV/BR-UEL7 in teat warts of dairy cows, highlighting the high genetic diversity of BPVs associated with teat papillomatosis.

  4. Detection of Mycobacterium avium subspecies paratuberculosis in tie-stall dairy herds using a standardized environmental sampling technique and targeted pooled samples

    PubMed Central

    Arango-Sabogal, Juan C.; Côté, Geneviève; Paré, Julie; Labrecque, Olivia; Roy, Jean-Philippe; Buczinski, Sébastien; Doré, Elizabeth; Fairbrother, Julie H.; Bissonnette, Nathalie; Wellemans, Vincent; Fecteau, Gilles

    2016-01-01

    Mycobacterium avium ssp. paratuberculosis (MAP) is the etiologic agent of Johne’s disease, a chronic contagious enteritis of ruminants that causes major economic losses. Several studies, most involving large free-stall herds, have found environmental sampling to be a suitable method for detecting MAP-infected herds. In eastern Canada, where small tie-stall herds are predominant, certain conditions and management practices may influence the survival and transmission of MAP and recovery (isolation). Our objective was to estimate the performance of a standardized environmental and targeted pooled sampling technique for the detection of MAP-infected tie-stall dairy herds. Twenty-four farms (19 MAP-infected and 5 non-infected) were enrolled, but only 20 were visited twice in the same year, to collect 7 environmental samples and 2 pooled samples (sick cows and cows with poor body condition). Concurrent individual sampling of all adult cows in the herds was also carried out. Isolation of MAP was achieved using the MGIT Para TB culture media and the BACTEC 960 detection system. Overall, MAP was isolated in 7% of the environmental cultures. The sensitivity of the environmental culture was 44% [95% confidence interval (CI): 20% to 70%] when combining results from 2 different herd visits and 32% (95% CI: 13% to 57%) when results from only 1 random herd visit were used. The best sampling strategy was to combine samples from the manure pit, gutter, sick cows, and cows with poor body condition. The standardized environmental sampling technique and the targeted pooled samples presented in this study is an alternative sampling strategy to costly individual cultures for detecting MAP-infected tie-stall dairies. Repeated samplings may improve the detection of MAP-infected herds. PMID:27408329

  5. Detection of Mycobacterium avium subspecies paratuberculosis in tie-stall dairy herds using a standardized environmental sampling technique and targeted pooled samples.

    PubMed

    Arango-Sabogal, Juan C; Côté, Geneviève; Paré, Julie; Labrecque, Olivia; Roy, Jean-Philippe; Buczinski, Sébastien; Doré, Elizabeth; Fairbrother, Julie H; Bissonnette, Nathalie; Wellemans, Vincent; Fecteau, Gilles

    2016-07-01

    Mycobacterium avium ssp. paratuberculosis (MAP) is the etiologic agent of Johne's disease, a chronic contagious enteritis of ruminants that causes major economic losses. Several studies, most involving large free-stall herds, have found environmental sampling to be a suitable method for detecting MAP-infected herds. In eastern Canada, where small tie-stall herds are predominant, certain conditions and management practices may influence the survival and transmission of MAP and recovery (isolation). Our objective was to estimate the performance of a standardized environmental and targeted pooled sampling technique for the detection of MAP-infected tie-stall dairy herds. Twenty-four farms (19 MAP-infected and 5 non-infected) were enrolled, but only 20 were visited twice in the same year, to collect 7 environmental samples and 2 pooled samples (sick cows and cows with poor body condition). Concurrent individual sampling of all adult cows in the herds was also carried out. Isolation of MAP was achieved using the MGIT Para TB culture media and the BACTEC 960 detection system. Overall, MAP was isolated in 7% of the environmental cultures. The sensitivity of the environmental culture was 44% [95% confidence interval (CI): 20% to 70%] when combining results from 2 different herd visits and 32% (95% CI: 13% to 57%) when results from only 1 random herd visit were used. The best sampling strategy was to combine samples from the manure pit, gutter, sick cows, and cows with poor body condition. The standardized environmental sampling technique and the targeted pooled samples presented in this study is an alternative sampling strategy to costly individual cultures for detecting MAP-infected tie-stall dairies. Repeated samplings may improve the detection of MAP-infected herds.

  6. Prevalence of and risk factors for bovine respiratory syncytial virus (BRSV) infection in non-vaccinated dairy and dual-purpose cattle herds in Ecuador.

    PubMed

    Saa, Luis Rodrigo; Perea, Anselmo; Jara, Diego Vinicio; Arenas, Antonio José; Garcia-Bocanegra, Ignacio; Borge, Carmen; Carbonero, Alfonso

    2012-10-01

    A cross-sectional study was carried out to determine the seroprevalence and risk factors associated with bovine respiratory syncytial virus (BRSV) 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 to February 2009. A questionnaire, which included variables related to cattle, health, management measures, and the environment, was filled out in each herd. Presence of antibodies against BRSV was analyzed using a commercial indirect ELISA test. A logistic regression model was used to determine risk factors associated with BRSV at herd level. The individual seroprevalence against BRSV in non-vaccinated herds in Ecuador was 80.48% [1,905/2,367; 95% confidence interval (CI) = 78.9-82.1]. The herd prevalence was 91.3% (316/346; 95% CI = 88.3-94.3), and the intra-herd prevalence ranged between 25% and 100% (mean, 90.47%). The logistic regression model showed that the existence of bordering cattle farms, the dual-purpose farms, and the altitude of the farm (more than 2,338 m above sea level) were risk factors associated with BRSV infection. This is the first study about BRSV prevalence in Ecuador. It shows the wide spread of the BRSV infection in the country. The risk factors found will help to design effective control strategies.

  7. Evaluation of Tunisian milk quality in dairy herds: Inter-relationship between chemical, physical and hygienic criteria.

    PubMed

    Gargouri, Ahmed; Hamed, Houda; Ben Ali, Besma; Elfeki, Abdelfettah; Gdoura, Radhouane

    2014-06-01

    The objective of this paper was to evaluate the global milk quality in Tunisian dairy herds. Samples of milk were analyzed for chemical, physical and hygienic parameters. Milk total solids, fat content and density were consistently correlated and one of them can be used as a chemical indicator of milk quality. The somatic cell count value of 689 × 10(3) /mL was higher than the recommended threshold. All milk samples were positive for the major pathogen Staphylococcus aureus. These hygienic parameters were related more closely with chloride content, minerals and electrical conductivity, which allows them to be used as indicators of mammary gland infection. It was concluded that milk producers have at hand rapid and easy tools for assessing the overall quality of milk.

  8. Cow and herd variation in milk urea nitrogen concentrations in lactating dairy cattle.

    PubMed

    Aguilar, M; Hanigan, M D; Tucker, H A; Jones, B L; Garbade, S K; McGilliard, M L; Stallings, C C; Knowlton, K F; James, R E

    2012-12-01

    Milk urea nitrogen (MUN) is correlated with N balance, N intake, and dietary N content, and thus is a good indicator of proper feeding management with respect to protein. It is commonly used to monitor feeding programs to achieve environmental goals; however, genetic diversity also exists among cows. It was hypothesized that phenotypic diversity among cows could bias feed management decisions when monitoring tools do not consider genetic diversity associated with MUN. The objective of the work was to evaluate the effect of cow and herd variation on MUN. Data from 2 previously published research trials and a field trial were subjected to multivariate regression analyses using a mixed model. Analyses of the research trial data showed that MUN concentrations could be predicted equally well from diet composition, milk yield, and milk components regardless of whether dry matter intake was included in the regression model. This indicated that cow and herd variation could be accurately estimated from field trial data when feed intake was not known. Milk urea N was correlated with dietary protein and neutral detergent fiber content, milk yield, milk protein content, and days in milk for both data sets. Cow was a highly significant determinant of MUN regardless of the data set used, and herd trended to significance for the field trial data. When all other variables were held constant, a percentage unit change in dietary protein concentration resulted in a 1.1mg/dL change in MUN. Least squares means estimates of MUN concentrations across herds ranged from a low of 13.6 mg/dL to a high of 17.3 mg/dL. If the observed MUN for the high herd were caused solely by high crude protein feeding, then the herd would have to reduce dietary protein to a concentration of 12.8% of dry matter to achieve a MUN concentration of 12 mg/dL, likely resulting in lost milk production. If the observed phenotypic variation is due to genetic differences among cows, genetic choices could result in

  9. Using dairy herd improvement records and clinical mastitis history to identify subclinical mastitis infections at dry-off.

    PubMed

    Torres, Audrey H; Rajala-Schultz, Päivi J; Degraves, Fred J; Hoblet, Kent H

    2008-05-01

    Interest in selective dry cow therapy (SDCT) has been increasing owing to concerns over development of antimicrobial resistance. Implementation of SDCT, however, requires a quick and cost-effective on-farm method for identifying cows for treatment and cows that can be left without treatment. The objective of the present study was to evaluate the use of clinical mastitis (CM) history and somatic cell counts (SCC) from monthly Dairy Herd Improvement (DHI) records in identification of infected and uninfected cows at dry-off. A total of 647 Holstein cows were classified as uninfected or infected at dry-off based on CM history and varying number of monthly SCC records (with three different SCC cut-offs). Cows were considered uninfected based on the following criteria: (1) SCC <100,000 cells/ml and no CM during the lactation; (2) SCC <200,000 cells/ml and no CM during the lactation; (3) as criterion two, but additionally a cow was also considered uninfected if it experienced a case of CM during the first 3 months of the lactation and the SCC was <100,000 cells/ml for the rest of the lactation; (4) SCC <300,000 cells/ml and no CM during the lactation; otherwise they were considered infected. Infected and uninfected cows at dry-off were most efficiently identified using three months' SCC records with a threshold of 200,000 cells/ml for cows without CM during the lactation and a threshold of 100,000 cells/ml during the rest of lactation for cows with CM during the first 90 days in milk. Moreover, this criterion also most efficiently identified cows infected with major pathogens only at dry-off. The success of the criteria used for identifying infected and uninfected cows will, however, depend on herd characteristics, such as prevalence of infection and type of pathogens present in the herd.

  10. Antibodies to bovine leukemia virus in a leukosis dairy herd and suggestions for control of the infection.

    PubMed Central

    Ferdinand, G A; Langston, A; Ruppanner, R; Drlica, S; Theilen, G H; Behymer, D E

    1979-01-01

    A closed herd of 765 Holstein-Friesian dairy cattle with a history of multiple cases of leukosis was tested for antibodies to bovine leukemia virus by the bovine leukemia-glycoprotein immunodiffusion test. A total of 355 animals (46.4%) were antibody positive. Prevalence was 60% in the 373 milking cows and 100% in the breeding bulls. Antibodies were present in 59% of newborn calves. Prevalence of antibodies was higher in older animals and cows in second lactation had a higher prevalence than cows in first lactation (72% vs 43%). Proposed control measures in this herd aim at preventing infection of calves, heifers and lactating cows by: 1) separating them into groups negative and positive for bovine leukemia virus antibodies, 2) not allowing calves to receive colstrum or milk from infected cows and 3) by using seronegative bulls for natural breeding tested at three month intervals. Calves should be tested after six months of age. Before this time calves of positive mothers should be treated as being positive. PMID:227552

  11. Effect of three programmes for the treatment of endometritis on the reproductive performance of a dairy herd.

    PubMed

    Heuwieser, W; Tenhagen, B A; Tischer, M; Lühr, J; Blum, H

    2000-03-18

    Three management programmes to improve the reproductive performance of a dairy herd were compared in a prospective controlled field study on one commercial farm. A total of 542 cows were examined for endometritis 22 to 28 days postpartum and assigned to one of three treatment groups: in group 1 the cows with signs of endometritis were treated with an intrauterine infusion of 100 ml of a 2 per cent polycondensated m-cresolsulphuric acid formaldehyde solution; in group 2 the cows with signs of endometritis were treated with an intrauterine infusion of 125 ml of a 20 per cent eucalyptus compositum solution; and in group 3 all the cows were injected intramuscularly with 0.75 mg of tiaprost, an analogue of prostaglandin F2alpha (PGF2alpha) at two-week intervals, starting on day 43, until they were inseminated. Thirty-four per cent of the cows showed signs of endometritis. In group 3, oestrus detection efficiency was significantly higher than in groups 1 and 2 (P<0.05), the interval to first service was shorter, and the cows had fewer days open than the cows in groups 1 and 2 (P<0.05). The results indicate that management programmes based on the strategic use of PGF2alpha are an effective alternative to traditional programmes based on rectal palpations and intrauterine infusions to control endometritis at a herd level.

  12. Capture-recapture analysis of East Coast fever in smallholder dairy herds in the Dar es Salaam region of Tanzania.

    PubMed

    Kivaria, F M; Noordhuizen, J P T M

    2010-05-01

    The prevalence of and case fatality rate due to East Coast fever (ECF) were estimated in 1402 dairy cattle in 87 small herds in the Dar es Salaam region of Tanzania, from January 2003 to January 2005 using a capture-recapture method. Information on clinical cases and deaths due to ECF were obtained from farm records and from a questionnaire-based cross-sectional survey conducted between July 2003 and March 2005 as part of longitudinal studies of bovine mastitis in these herds. The number of clinical cases identified was 567 (from farm records) and 496 (from the questionnaire), and the number of deaths recorded were 305 (from farm records) and 251 (from the questionnaire). In all, 450 clinical cases and 191 deaths due to ECF were identified from the two sources, giving an observed prevalence of 32% (CI(95%) 30-35%) and observed case fatality rate of 42% (CI(95%) 38-47%). Following application of the capture-recapture method, the estimated number of clinical cases and deaths was 625 (CI(95%) 617-633) and 401 (CI(95%) 384-418), respectively. The respective prevalence and case fatality rates were 45% (CI(95%) 41-48%) and 64% (CI(95%) 60-68%). The estimates obtained using the capture-recapture method are higher than those identified by traditional cross-sectional studies conducted in the same study area, and probably provide a more accurate epidemiological picture of ECF in this region of Tanzania.

  13. Somatic cell counts, mastitis and milk production in selected Ontario dairy herds.

    PubMed Central

    Barnum, D A; Meek, A H

    1982-01-01

    Somatic cell counts were performed monthly on bulk tank milk samples for all producers in the Ontario counties of Hastings, Lennox/Addington and Prince Edward throughout 1978 and 1979. Other data were obtained via a structured questionnaire and from the records of the Ontario Milk Marketing Board. Many producers have not adopted practices that have been advocated for the integrated control of mastitis. For example, 43.3% of producers surveyed used single service paper towels, 63.3% regularly used teat dip and 56.5% dry cow therapy. The mean of the average monthly somatic cell count for all producers for 1978 was 621.1 x 10(3) cells/mL. This latter value was used to divide the producers into case (higher than average) and control (lower than average) groups. Control herds averaged 95.9 liters more shipped milk per cow per month than case herds. Milk from control herds averaged 0.22 percentage points higher than case herds for each of average fat and lactose, and 0.16 percentage points higher for protein. The linear regression of monthly shipped milk on the respective monthly bulk tank somatic cell count indicated a loss of 13.26 L/cow/month for each 100,000 increase in somatic cell count. PMID:7200385

  14. The association of culling and death rate within 30 days after calving with productivity or reproductive performance in dairy herds in Fukuoka, Southern Japan

    PubMed Central

    GOTO, Akira; NAKADA, Ken; KATAMOTO, Hiromu

    2015-01-01

    The incidence of peripartum disorders in dairy herds negatively influences productivity and reproductive performance. Concrete data from local areas are helpful for explaining the importance of peripartum management to dairy farmers. This study was conducted to clarify the association of culling and death rate within 30 days after calving with productivity or reproductive performance in 179 dairy herds in Fukuoka, Southern Japan. A database was compiled from the records of the Livestock Improvement Association of Japan, the Dairy Cooperative Association and the Federation of Agricultural Mutual Relief Association. In this study, we created a comprehensive database of dairy farm production data for epidemiological analysis and used a general linear mixed model to analyze the association of culling and death rate within 30 days after calving with milk production or reproductive performance. The database can be used to describe, analyze and predict the risk of production. A cross-sectional analysis with contrasts was applied to investigate the association of cows served by AI/all cows, pregnant cows/cows served by AI, days open, milk yield and somatic cell counts with culling and death rate within 30 days after calving. The days open value significantly increased with increasing rate of culling and death within 30 days after calving (P for trend <0.001). No significant differences were found for the other comparisons. Our data suggest that proper feeding and management in the dry period may lead to improved postpartum reproductive performance in this dairy cow cohort. PMID:26666177

  15. Prevalence of exposure to bovine viral diarrhoea virus (BVDV) and bovine herpesvirus-1 (BoHV-1) in Irish dairy herds.

    PubMed

    Sayers, R G; Byrne, N; O'Doherty, E; Arkins, S

    2015-06-01

    Bovine viral diarrhoea virus (BVDV) and bovine herpesvirus 1 (BoHV-1) are contagious bovine viral agents. The objectives of this study were to use quarterly bulk milk and 'spot' testing of unvaccinated youngstock to establish the national prevalence of exposure to BVDV and/or BoHV-1 in Irish dairy herds. Seasonality of bulk milk ELISA results was also examined. From a geographically representative population of 305 dairy herds, 88% and 80% of herds yielded mean annual positive bulk milk readings for BVDV and BoHV-1, respectively. Of these, 61% were vaccinated against BVDV and 12% against BoHV-1. A total of 2171 serum samples from weanlings having a mean age of 291 days yielded 543 (25%) seropositive for BVDV, and 117 (5.4%) seropositive for BoHV-1. A significant seasonal trend in bulk milk antibody ELISA readings and herd status was recorded for BVDV, with more herds categorised as positive in the latter half of the year.

  16. Effect of calving interval and parity on milk yield per feeding day in Danish commercial dairy herds.

    PubMed

    Lehmann, J O; Fadel, J G; Mogensen, L; Kristensen, T; Gaillard, C; Kebreab, E

    2016-01-01

    The idea of managing cows for extended lactations rather than lactations of the traditional length of 1 yr primarily arose from observations of increasing problems with infertility and cows being dried off with high milk yields. However, it is vital for the success of extended lactation practices that cows are able to maintain milk yield per feeding day when the length of the calving interval (CInt) is increased. Milk yield per feeding day is defined as the cumulated lactation milk yield divided by the sum of days between 2 consecutive calvings. The main objective of this study was to investigate the milk production of cows managed for lactations of different lengths, and the primary aim was to investigate the relationship between CInt, parity, and milk yield. Five measurements of milk yield were used: energy-corrected milk (ECM) yield per feeding day, ECM yield per lactating day, cumulative ECM yield during the first 305 d of lactation, as well as ECM yield per day during early and late lactation. The analyses were based on a total of 1,379 completed lactations from cows calving between January 2007 and May 2013 in 4 Danish commercial dairy herds managed for extended lactation for several years. Herd-average CInt length ranged from 414 to 521 d. The herds had Holstein, Jersey, or crosses between Holstein, Jersey, and Red Danish cows with average milk yields ranging from 7,644 to 11,286 kg of ECM per cow per year. A significant effect of the CInt was noted on all 5 measurements of milk yield, and this effect interacted with parity for ECM per feeding day, ECM per lactating day and ECM per day during late lactation. The results showed that cows were at least able to produce equivalent ECM per feeding day with increasing CInt, and that first- and second-parity cows maintained ECM per lactating day. Cows with a CInt between 17 and 19 mo produced 476 kg of ECM more during the first 305 d compared with cows with a CInt of less than 13 mo. Furthermore, early

  17. Effects of folic acid and vitamin B12 supplementation on culling rate, diseases, and reproduction in commercial dairy herds.

    PubMed

    Duplessis, M; Girard, C L; Santschi, D E; Laforest, J-P; Durocher, J; Pellerin, D

    2014-01-01

    This study was undertaken to determine the effect of a combined folic acid and vitamin B12 supplement given in early lactation on culling rate, metabolic disorders and other diseases, and reproduction in commercial dairy herds. A total of 805 cows (271 primiparous and 534 multiparous cows) in 15 commercial dairy herds were involved. Every 2mo from February to December 2010 and within each herd, cows were assigned according to parity, previous 305-d milk production, and calving interval to 5mL of either (1) saline 0.9% NaCl (control group) or (2) 320mg of folic acid + 10mg of vitamin B12 (vitamin group). Treatments were administered weekly by intramuscular injections starting 3wk before the expected calving date until 8wk after parturition. A total of 221 cows were culled before the next dry period. Culling rate was not affected by treatment and was 27.5%; culling rate was greater for multiparous (32.2%) than for primiparous cows (18.8%). Within the first 60d in milk (DIM), 47 cows were culled, representing 21.3% of total culling, and no treatment effect was noted. Ketosis incidence based on a threshold ≥100µmol/L of β-hydroxybutyrate in milk was 38.3±2.9% for the vitamin group and 41.8±3.0% for the control group and was not affected by treatment. The combined supplement of folic acid and vitamin B12 did not decrease incidence of retained placenta, displaced abomasum, milk fever, metritis, or mastitis. However, the incidence of dystocia decreased by 50% in multiparous cows receiving the vitamin supplement, although no effect was observed in primiparous cows. The first breeding postpartum for multiparous cows occurred 3.8d earlier with the vitamin supplement compared with controls, whereas no treatment effect was seen for primiparous cows. Days open, first- and second-breeding conception rates, number of breedings per conception, and percentage of cows pregnant at 150 DIM were not affected by treatment. The reduced percentage of dystocia combined with the

  18. Serosurvey of Coxiella burnetii infection in dairy goat herds in Ontario. A comparison of two methods of enzyme-linked immunosorbent assay.

    PubMed Central

    Lang, G H

    1988-01-01

    Two technical variations of enzyme-linked immunosorbent assay for the detection of antibodies to Coxiella burnetii were compared in this serosurvey on 20 Ontario dairy goat herds. Both a trichloracetic acid extract and a coctoantigen of purified coxiellas were used to sensitize the microtitration plates. Technical differences related to coating pH, serum dilutions tested and interpretation of results. Results agreed in 98.6% of sera examined, the differing sera were in the low titer borderline range. Only 20% of the herds had seroreactors. PMID:3349400

  19. Effects of dairy system, herd within dairy system, and individual cow characteristics on the volatile organic compound profile of ripened model cheeses.

    PubMed

    Bergamaschi, M; Aprea, E; Betta, E; Biasioli, F; Cipolat-Gotet, C; Cecchinato, A; Bittante, G; Gasperi, F

    2015-04-01

    The objective of this work was to study the effect of dairy system, herd within dairy system, and characteristics of individual cows (parity, days in milk, and daily milk yield) on the volatile organic compound profile of model cheeses produced under controlled conditions from the milk of individual cows of the Brown Swiss breed. One hundred fifty model cheeses were selected from 1,272 produced for a wider study of the phenotypic and genetic variability of Brown Swiss cows. In our study, we selected 30 herds representing 5 different dairy systems. The cows sampled presented different milk yields (12.3-43.2kg/d), stages of lactation (10-412 d in milk), and parity (1-7). In total, 55 volatile compounds were detected by solid-phase microextraction and gas chromatography-mass spectrometry, including 14 alcohols, 13 esters, 11 free fatty acids, 8 ketones, 4 aldehydes, 3 lactones, 1 terpene, and 1 pyrazine. The most important sources of variation in the volatile organic profiles of model cheeses were dairy system (18 compounds) and days in milk (10 compounds), followed by parity (3 compounds) and milk yield (5 compounds). The model cheeses produced from the milk of tied cows reared on traditional farms had lower quantities of 3-methyl-butan-1-ol, 6-pentyloxan-2-one, 2-phenylethanol, and dihydrofuran-2(3H)-one compared with those reared in freestalls on modern farms. Of these, milk from farms using total mixed rations had higher contents of alcohols (hexan-1-ol, octan-1-ol) and esters (ethyl butanoate, ethyl pentanoate, ethyl hexanoate, and ethyl octanoate) and lower contents of acetic acid compared with those using separate feeds. Moreover, dairy systems that added silage to the total mixed ration produced cheeses with lower levels of volatile organic compounds, in particular alcohols (butan-1-ol, pentan-1-ol, heptan-1-ol), compared with those that did not. The amounts of butan-2-ol, butanoic acid, ethyl-2-methylpropanoate, ethyl-3-methylbutanoate, and 6-propyloxan-2-one

  20. Multivariate factor analysis of detailed milk fatty acid profile: Effects of dairy system, feeding, herd, parity, and stage of lactation.

    PubMed

    Mele, M; Macciotta, N P P; Cecchinato, A; Conte, G; Schiavon, S; Bittante, G

    2016-12-01

    We investigated the potential of using multivariate factor analysis to extract metabolic information from data on the quantity and quality of milk produced under different management systems. We collected data from individual milk samples taken from 1,158 Brown Swiss cows farmed in 85 traditional or modern herds in Trento Province (Italy). Factor analysis was carried out on 47 individual fatty acids, milk yield, and 5 compositional milk traits (fat, protein, casein, and lactose contents, somatic cell score). According to a previous study on multivariate factor analysis, a variable was considered to be associated with a specific factor if the absolute value of its correlation with the factor was ≥0.60. The extracted factors were representative of the following 12 groups of fatty acids or functions: de novo fatty acids, branched fatty acid-milk yield, biohydrogenation, long-chain fatty acids, desaturation, short-chain fatty acids, milk protein and fat contents, odd fatty acids, conjugated linoleic acids, linoleic acid, udder health, and vaccelenic acid. Only 5 fatty acids showed small correlations with these groups. Factor analysis suggested the existence of differences in the metabolic pathways for de novo short- and medium-chain fatty acids and Δ(9)-desaturase products. An ANOVA of factor scores highlighted significant effects of the dairy farming system (traditional or modern), season, herd/date, parity, and days in milk. Factor behavior across levels of fixed factors was consistent with current knowledge. For example, compared with cows farmed in modern herds, those in traditional herds had higher scores for branched fatty acids, which were inversely associated with milk yield; primiparous cows had lower scores than older cows for de novo fatty acids, probably due to a larger contribution of lipids mobilized from body depots on milk fat yield. The statistical approach allowed us to reduce a large number of variables to a few latent factors with biological

  1. Dynamics of Escherichia coli Virulence Factors in Dairy Herds and Farm Environments in a Longitudinal Study in the United States

    PubMed Central

    Lambertini, Elisabetta; Karns, Jeffrey S.; Van Kessel, Jo Ann S.; Cao, Huilin; Schukken, Ynte H.; Wolfgang, David R.; Smith, Julia M.

    2015-01-01

    Pathogenic Escherichia coli or its associated virulence factors have been frequently detected in dairy cow manure, milk, and dairy farm environments. However, it is unclear what the long-term dynamics of E. coli virulence factors are and which farm compartments act as reservoirs. This study assessed the occurrence and dynamics of four E. coli virulence factors (eae, stx1, stx2, and the gamma allele of the tir gene [γ-tir]) on three U.S. dairy farms. Fecal, manure, water, feed, milk, and milk filter samples were collected from 2004 to 2012. Virulence factors were measured by postenrichment quantitative PCR (qPCR). All factors were detected in most compartments on all farms. Fecal and manure samples showed the highest prevalence, up to 53% for stx and 21% for γ-tir in fecal samples and up to 84% for stx and 44% for γ-tir in manure. Prevalence was low in milk (up to 1.9% for stx and 0.7% for γ-tir). However, 35% of milk filters were positive for stx and 20% were positive for γ-tir. All factors were detected in feed and water. Factor prevalence and levels, expressed as qPCR cycle threshold categories, fluctuated significantly over time, with no clear seasonal signal independent from year-to-year variability. Levels were correlated between fecal and manure samples, and in some cases autocorrelated, but not between manure and milk filters. Shiga toxins were nearly ubiquitous, and 10 to 18% of the lactating cows were potential shedders of E. coli O157 at least once during their time in the herds. E. coli virulence factors appear to persist in many areas of the farms and therefore contribute to transmission dynamics. PMID:25911478

  2. Atypical rumen acidosis in a dairy herd from whiskey distillery by-products.

    PubMed

    Davenport, D F; Kerr, L A

    2001-06-01

    Decreased milk and reproductive performance, high incidence of gastrointestinal surgeries, and acute deaths were investigated in a herd of Holstein cows. The health problems were due to abnormally low rumen pH's from ingestion of 30 gal/hd/d of a 3.4 pH liquid feed ingredient. A combination of acid neutralizing agents (calcium hydroxide plus sodium carbonate) alleviated the toxic effects of the feed ingredient.

  3. Major outbreak of suspected botulism in a dairy herd in the Republic of Ireland.

    PubMed

    Sharpe, A E; Brady, C P; Byrne, W; Moriarty, J; O'Neill, P; McLaughlin, J G

    2008-03-29

    This is the first report of a major outbreak of a paralytic disease in cattle on a farm in the Republic of Ireland. Thirty-six of 65 dairy cows were euthanased or died. A presumptive diagnosis of botulism was made on the basis of the clinical signs, the duration of the outbreak and the postmortem findings, and by ruling out other differential diagnoses.

  4. Current Research on Molasses as an Alternative Energy Source for Organic Dairy Herds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    As organic grain prices have increased and organic milk prices have decreased, dairy farmers are seeking lower-cost supplementation strategies. Sugarcane molasses, a rich source of sucrose, seems to be a viable option as a source of energy. Molasses frequently costs less per pound of dry matter than...

  5. Dynamics of E.coli virulence factors in dairy cow herds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background. Dairy farms are known reservoirs of entero-pathogenic E. coli (EPEC). EPEC, or the virulence factors associated with pathogenicity, have been detected in manure, milk, and the farm environment. However, it is unclear which farm compartments are reservoirs contributing to EPEC persistence...

  6. Discovery of Bovine Digital Dermatitis-Associated Treponema spp. in the Dairy Herd Environment by a Targeted Deep-Sequencing Approach

    PubMed Central

    Nielsen, Martin W.; Ingerslev, Hans-Christian; Boye, Mette; Jensen, Tim K.

    2014-01-01

    The bacteria associated with the infectious claw disease bovine digital dermatitis (DD) are spirochetes of the genus Treponema; however, their environmental reservoir remains unknown. To our knowledge, the current study is the first report of the discovery and phylogenetic characterization of rRNA gene sequences from DD-associated treponemes in the dairy herd environment. Although the spread of DD appears to be facilitated by wet floors covered with slurry, no DD-associated treponemes have been isolated from this environment previously. Consequently, there is a lack of knowledge about the spread of this disease among cows within a herd as well as between herds. To address the issue of DD infection reservoirs, we searched for evidence of DD-associated treponemes in fresh feces, in slurry, and in hoof lesions by deep sequencing of the V3 and V4 hypervariable regions of the 16S rRNA gene coupled with identification at the operational-taxonomic-unit level. Using treponeme-specific primers in this high-throughput approach, we identified small amounts of DNA (on average 0.6% of the total amount of sequence reads) from DD-associated treponemes in 43 of 64 samples from slurry and cow feces collected from six geographically dispersed dairy herds. Species belonging to the Treponema denticola/Treponema pedis-like and Treponema phagedenis-like phylogenetic clusters were among the most prevalent treponemes in both the dairy herd environment and the DD lesions. By the high-throughput approach presented here, we have demonstrated that cow feces and environmental slurry are possible reservoirs of DD-associated treponemes. This method should enable further clarification of the etiopathogenesis of DD. PMID:24814794

  7. Impact of three inactivated bovine viral diarrhoea virus vaccines on bulk milk p80 (NS3) ELISA test results in dairy herds.

    PubMed

    Sayers, Ríona G; Sayers, Gearóid P; Graham, David A; Arkins, Sean

    2015-07-01

    Bovine viral diarrhoea virus (BVDV) is endemic in many countries and vaccines are used as a component of control and eradication strategies. Surveillance programmes to detect exposure to BVDV often incorporate the use of bulk milk (BM) testing for antibodies against BVDV p80 (NS3), but vaccination can interfere with these results. The aim of this study was to evaluate whether BVDV vaccines would confound BM testing for specific antibodies in a nationally representative group of commercial dairy farms in the Republic of Ireland. A total of 256 commercial dairy herds were included in the statistical analysis. Quarterly BM or serum samples from selected weanling heifers (unvaccinated homeborn youngstock) were assessed by ELISA for antibodies against the BVDV p80 subunit and whole virus. Wilcoxon rank-sum and receiver operating characteristic (ROC) analyses were used to examine differences among groups vaccinated with one of three commercially available inactivated BVDV vaccines. Two of the three vaccines showed evidence of interference with ELISA testing of BM samples. ROC analysis highlighted that one vaccine did not reduce the discriminatory power of the BVDV p80 ELISA for identification of herds with evidence of recent BVDV circulation, when compared with unvaccinated herds; thus, administration of this vaccine would allow uncomplicated interpretation of BM ELISA test results in vaccinated seropositive herds. Seasonal differences in BM antibody results were identified, suggesting that the latter half of lactation is the most suitable time for sampling dairy herds containing predominantly spring calving cows. The results of the present study are likely to prove useful in countries allowing vaccination during or following BVDV eradication, where BM testing is required as part of the surveillance strategy.

  8. Optimal feeding systems for small-scale dairy herds in the North West Province, South Africa.

    PubMed

    Manzana, N Patience; McCrindle, Cheryl M E; Sebei, P Julius; Prozesky, Leon

    2014-07-09

    Land redistribution was legislated in 1994; it was designed to resolve historical imbalances inland ownership in South Africa. Between 2002 and 2006, a longitudinal observational studywas conducted with 15 purposively selected small-scale dairy farmers in a land redistributionproject in Central North West Province. Four farmers left the project over the period. For thepurposes of this study, a small-scale dairy farm was defined as a farm that produces less than500 L of milk a day, irrespective of the number of cows or size of the farm. The study wasconducted in three phases. In the first phase, situational analysis using participatory ruralappraisal (PRA) and observation was used to outline the extent of the constraints and designappropriate interventions. Feeds that were used were tested and evaluated. In the secondphase, three different feeding systems were designed from the data obtained from PRA. Thesewere: (1) A semi-intensive farm-based ration using available crops, pastures and crop residueswith minimal rations purchased. (2) An intensive, zero-grazing dairy system using a totalmixed ration. (3) A traditional, extensive or dual-purpose system, where the calf drank fromthe cow until weaning and milking was done only once a day. In the third phase, adoptionwas monitored. By July 2006, all remaining farmers had changed to commercially formulatedrations or licks and the body condition score of the cows had improved. It was concluded thatveterinary extension based on PRA and a holistic systems approach was a good option forsuch complex problems. Mentoring by commercial dairy farmers, veterinary and extensionservices appeared to be viable. Further research should be done to optimise the traditionalmodel of dairy farming, as this was relatively profitable, had a lower risk and was less labourintensive.

  9. 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

  10. Cluster analysis of fasciolosis in dairy cow herds in Munster province of Ireland and detection of major climatic and environmental predictors of the exposure risk.

    PubMed

    Selemetas, Nikolaos; Phelan, Paul; O'Kiely, Padraig; de Waal, Theo

    2015-03-19

    Fasciolosis caused by Fasciola hepatica is a widespread parasitic disease in cattle farms. The aim of this study was to detect clusters of fasciolosis in dairy cow herds in Munster Province, Ireland and to identify significant climatic and environmental predictors of the exposure risk. In total, 1,292 dairy herds across Munster was sampled in September 2012 providing a single bulk tank milk (BTM) sample. The analysis of samples by an in-house antibody-detection enzyme-linked immunosorbent assay (ELISA), showed that 65% of the dairy herds (n = 842) had been exposed to F. hepatica. Using the Getis-Ord Gi* statistic, 16 high-risk and 24 low-risk (P <0.01) clusters of fasciolosis were identified. The spatial distribution of high-risk clusters was more dispersed and mainly located in the northern and western regions of Munster compared to the low-risk clusters that were mostly concentrated in the southern and eastern regions. The most significant classes of variables that could reflect the difference between high-risk and low-risk clusters were the total number of wet-days and rain-days, rainfall, the normalized difference vegetation index (NDVI), temperature and soil type. There was a bigger proportion of well-drained soils among the low-risk clusters, whereas poorly drained soils were more common among the high-risk clusters. These results stress the role of precipitation, grazing, temperature and drainage on the life cycle of F. hepatica in the temperate Irish climate. The findings of this study highlight the importance of cluster analysis for identifying significant differences in climatic and environmental variables between high-risk and low-risk clusters of fasciolosis in Irish dairy herds.

  11. Animal health and welfare planning improves udder health and cleanliness but not leg health in Austrian dairy herds.

    PubMed

    Tremetsberger, Lukas; Leeb, Christine; Winckler, Christoph

    2015-10-01

    Animal health and welfare planning is considered an important tool for herd management; however, its effectiveness is less well known. The aim of this study was to conduct animal health and welfare planning on 34 Austrian dairy farms and to evaluate changes in health and welfare after 1 yr. After an initial assessment using the Welfare Quality protocol (Welfare Quality Consortium, Lelystad, the Netherlands), results were reported back to the farmers. Health and welfare area(s) in which both the farmer and the researcher regarded improvement as important were discussed. Management practices and husbandry measures were chosen according to the respective farm situation. One year after interventions had been initiated, farms were reassessed, and the degree of implementation of improvement measures was recorded. The average implementation rate was 57% and thus relatively high when compared with other studies. High degrees of implementation were achieved related to cleanliness and udder health, at 77 and 63%, respectively. Intervention measures addressing udder health were mostly easy to incorporate in the daily routine and led to a reduced somatic cell score, whereas this score increased in herds without implementation of measures. The decrease in cows with dirty teats was more pronounced when measures were implemented compared with control farms. The implementation rate regarding leg health (46%) was comparably low in the present study, and leg health did not improve even when measures were implemented. Lying comfort, social behavior, and human-animal relationship did not require interventions and were therefore seldom chosen by farmers as part of health and welfare plans. In conclusion, the structured, participatory process of animal health and welfare planning appears to be a promising way to improve at least some animal health and welfare issues.

  12. The effect of somatic cell count data adjustment and interpretation, as outlined in European Union legislation, on herd eligibility to supply raw milk for processing of dairy products.

    PubMed

    More, S J; Clegg, T A; Lynch, P J; O'Grady, L

    2013-06-01

    Somatic cell count (SCC) limits are a key component of national and international regulation for milk quality. As yet, very limited work has been published on SCC regulatory standards, including on the effect of different approaches to SCC data adjustment and interpretation. This study examines the effect of SCC data adjustment and interpretation, as outlined in current European Union (EU) legislation, on herd eligibility to supply raw milk for processing of dairy products for human consumption, using Irish data for illustration. The study used Irish milk-recording data as a proxy for bulk tank SCC (BTSCC) data, to calculate an unadjusted monthly SCC value for each herd during each month of participation. Subsequently, 4 data adjustments were applied, as outlined in EU and national legislation: seasonal adjustment; 3-mo rolling geometric average, without accounting for a break in the supply; 3-mo rolling geometric average, after accounting for a break in the supply; and seasonal adjustment and 3-mo rolling geometric average combined, after accounting for a break in the supply. Analyses were conducted to examine the effect, during the period from 2004 to 2010, of data adjustment on the percentage of herds with herd SCC >400,000 cells/mL. In all, 4 interpretation scenarios, incorporating different data adjustment combinations, were used to estimate herd eligibility (compliant, under warning, or suspended, as defined by legislation) to supply raw milk for processing. The 4 methods of data adjustment each led to a sizable reduction (6.7, 5.0, 5.3, and 11.1 percentage points, respectively, compared with the unadjusted data) in the percentage of herds exceeding a herd SCC of 400,000 cells/mL. Herd eligibility varied by interpretation scenarios, in particular those incorporating seasonal adjustment. The study provides new perspectives on the effect of data adjustment on herd SCC and of interpretation scenarios on herd eligibility. The results provide an illustrative

  13. 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

  14. Herd-level relationship between antimicrobial use and presence or absence of antimicrobial resistance in gram-negative bovine mastitis pathogens on Canadian dairy farms.

    PubMed

    Saini, Vineet; McClure, J T; Scholl, Daniel T; DeVries, Trevor J; Barkema, Herman W

    2013-08-01

    Concurrent data on antimicrobial use (AMU) and resistance are needed to contain antimicrobial resistance (AMR) in bacteria. The present study examined a herd-level association between AMU and AMR in Escherichia coli (n=394) and Klebsiella species (n=139) isolated from bovine intramammary infections and mastitis cases on 89 dairy farms in 4 regions of Canada [Alberta, Ontario, Québec, and Maritime Provinces (Prince Edward Island, Nova Scotia, and New Brunswick)]. Antimicrobial use data were collected using inventory of empty antimicrobial containers and antimicrobial drug use rate was calculated to quantify herd-level AMU. Minimum inhibitory concentrations (MIC) were determined using Sensititre National Antimicrobial Resistance Monitoring System (NARMS) gram-negative MIC plate (Trek Diagnostic Systems Inc., Cleveland, OH). Isolates were classified as susceptible, intermediate, or resistant. Intermediate and resistant category isolates were combined to form an AMR category, and multivariable logistic regression models were built to determine herd-level odds of AMR to tetracycline, ampicillin, cefoxitin, chloramphenicol, trimethoprim-sulfamethoxazole combination, sulfisoxazole, streptomycin and kanamycin in E. coli isolates. In the case of Klebsiella species isolates, logistic regression models were built for tetracycline and sulfisoxazole; however, no associations between AMU and AMR in Klebsiella species were observed. Ampicillin-intermediate or -resistant E. coli isolates were associated with herds that used intramammarily administered cloxacillin, penicillin-novobiocin combination, and cephapirin used for dry cow therapy [odds ratios (OR)=26, 32, and 189, respectively], and intramammary ceftiofur administered for lactating cow therapy and systemically administered penicillin (OR=162 and 2.7, respectively). Use of systemically administered penicillin on a dairy farm was associated with tetracycline and streptomycin-intermediate or -resistant E. coli isolates (OR=5

  15. Evaluation of environmental fecal culture for Mycobacterium avium subspecies paratuberculosis detection in dairy herds and association with apparent within-herd prevalence

    PubMed Central

    Lavers, Carrie J.; McKenna, Shawn L.B.; Dohoo, Ian R.; Barkema, Herman W.; Keefe, Greg P.

    2013-01-01

    This study evaluated test characteristics of environmental culture (EC) for the detection of Mycobacterium avium subspecies paratuberculosis (MAP) in 32 herds over a 2-year period. Individual fecal samples were collected every 6 mo and environmental samples every 3 mo. Individual fecal culture was performed on samples from positive pools. Samples were cultured in broth, with confirmatory polymerase chain reaction performed on positive fecal samples. Repeated measures were accounted for using GEE logistic models. Relative to a MAP herd-status based on all pooled fecal culture results collected during the study, sensitivity of a set of 6 EC-samples collected from prescribed locations within the herd environment (EC-6) was 71% [95% confidence interval (CI): 49% to 86%] and specificity was 99% (95% CI: 95% to 100%). Sensitivity of EC increased as apparent within-herd fecal culture prevalence (aWHP) increased. The estimated aWHP increased as the proportion of positive EC-samples within an EC-6 set increased. Environmental culture is an acceptable tool for herd diagnosis of MAP in low-prevalence herds. PMID:24179240

  16. Evaluation of testing strategies to identify infected animals at a single round of testing within dairy herds known to be infected with Mycobacterium avium ssp. paratuberculosis.

    PubMed

    More, S J; Cameron, A R; Strain, S; Cashman, W; Ezanno, P; Kenny, K; Fourichon, C; Graham, D

    2015-08-01

    As part of a broader control strategy within herds known to be infected with Mycobacterium avium ssp. paratuberculosis (MAP), individual animal testing is generally conducted to identify infected animals for action, usually culling. Opportunities are now available to quantitatively compare different testing strategies (combinations of tests) in known infected herds. This study evaluates the effectiveness, cost, and cost-effectiveness of different testing strategies to identify infected animals at a single round of testing within dairy herds known to be MAP infected. A model was developed, taking account of both within-herd infection dynamics and test performance, to simulate the use of different tests at a single round of testing in a known infected herd. Model inputs included the number of animals at different stages of infection, the sensitivity and specificity of each test, and the costs of testing and culling. Testing strategies included either milk or serum ELISA alone or with fecal culture in series. Model outputs included effectiveness (detection fraction, the proportion of truly infected animals in the herd that are successfully detected by the testing strategy), cost, and cost-effectiveness (testing cost per true positive detected, total cost per true positive detected). Several assumptions were made: MAP was introduced with a single animal and no management interventions were implemented to limit within-herd transmission of MAP before this test. In medium herds, between 7 and 26% of infected animals are detected at a single round of testing, the former using the milk ELISA and fecal culture in series 5 yr after MAP introduction and the latter using fecal culture alone 15 yr after MAP introduction. The combined costs of testing and culling at a single round of testing increases with time since introduction of MAP infection, with culling costs being much greater than testing costs. The cost-effectiveness of testing varied by testing strategy. It was also

  17. Synergy between selection for production and longevity and the use of extended lactation: insights from a resource allocation model in a dairy goat herd.

    PubMed

    Douhard, F; Tichit, M; Amer, P R; Friggens, N C

    2014-11-01

    Although most of the genetic progress in production efficiency is achieved through selection at a global scale, locally, farm managers can also influence the selection process to better match genotypes and their varying herd environment. This study focused on the influence of a particular management decision--the use of extended lactation (EL) in dairy goat production systems--as it affects the survival and reproduction rates at the herd level, which may then shape different long-term selection responses. The objective was to understand and quantify the influences of EL and variability in achieved intake level on the responses to selection for production, reproduction, and longevity. An animal model of resource allocation between life functions was applied to the dairy goat. It predicts the trajectory of change in the herd genetic composition as affected by the feeding level and the selection pressure applied by the manager. During 40 yr, goats were selected for milk yield, reproduction, and, with a different selection weight for age (WAGE), for longevity. Under varying achieved intake levels, increasing WAGE improved the survival rate but a nonlinear effect was observed for the average milk yield and BCS. When moderately increasing WAGE from 0, resources were reallocated from lactation towards body reserves and survival, which led to a trade-off at the herd level between improving survival and BCS and increasing milk yield. When further increasing WAGE, old females became systematically preferred regardless of their reproductive status and the proportion of EL in the herd increased. Females undergoing EL had reduced energetic costs of reproduction, which improved their probability of survival. Across generations, an increased herd incidence of EL led to a relaxation of the selection pressure on the resource allocation to body reserves, which is normally imposed by the manager's priority to achieve successful reproduction at each mating. As selection for longevity

  18. 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.

  19. Field trials of a vaccine against bovine mastitis. 2. Evaluation in two commercial dairy herds.

    PubMed

    Calzolari, A; Giraudo, J A; Rampone, H; Odierno, L; Giraudo, A T; Frigerio, C; Bettera, S; Raspanti, C; Hernández, J; Wehbe, M; Mattea, M; Ferrari, M; Larriestra, A; Nagel, R

    1997-05-01

    A vaccine against bovine mastitis was developed. The vaccine was based on inactivated, highly encapsulated Staphylococcus aureus cells; a crude extract of Staph. aureus exopolysaccharides; and inactivated unencapsulated Staph. aureus and Streptococcus spp. cells. In this study, the vaccine was evaluated in 164 cows from two commercial dairies (A and B) during a 4-mo period. Two doses of the vaccine were administered subcutaneously to 82 cows in the brachiocephalicus muscle of the neck within a 4-wk interval. The results of this trial revealed significantly fewer intramammary infections caused by Staph. aureus at various levels of severity (clinical, subclinical, and latent) in cows that were vaccinated. The odds ratios of all types of intrammammary infections caused by Staph. aureus for dairies A and B, which were determined by a logistic model, were 1.84 and 1.89, respectively, for quarters of vaccinated cows and quarters of control cows. The colony counts for Staph. aureus in milk from infected quarters of vaccinated cows were significantly lower than those in milk from infected quarters of control cows. Also, the somatic cell counts per milliliter in milk from vaccinated cows were significantly decreased when the initial somatic cell count was < 500,000 cells/ml at the start of the trial. The vaccine had no observable effect on fat production in milk or on streptococcal infections.

  20. A herd health approach to dairy cow nutrition and production diseases of the transition cow.

    PubMed

    Mulligan, F J; O'Grady, L; Rice, D A; Doherty, M L

    2006-12-01

    This paper presents a practical, on-farm approach for the monitoring and prevention of production disease in dairy cattle. This integrated approach, should be used in an interdisciplinary way by farmers, veterinarians, nutrition advisors and other relevant professionals for the improvement of animal health and welfare and producer profitability. The key areas that form the basis for this approach are body condition score management, negative energy balance, hypocalcaemia, rumen health and trace element status. Monitoring criteria are described for each of these key areas, which when considered collectively, will facilitate the assessment of dairy cow health with regard to clinical and subclinical disease. The criteria, which are informed by published scientific literature, are based on farm management and environmental factors, clinical data, milk production records, dietary analysis, and assessment of blood and liver concentrations of various metabolites or trace elements. The aim is to review the efficacy of production disease control measures currently in place, and if necessary to modify them or formulate new ones.

  1. Comparison of nutritional quality between conventional and organic dairy products: a meta-analysis.

    PubMed

    Palupi, Eny; Jayanegara, Anuraga; Ploeger, Angelika; Kahl, Johannes

    2012-11-01

    As a contribution to the debate on the comparison of nutritional quality between conventional versus organic products, the present study would like to provide new results on this issue specifically on dairy products by integrating the last 3 years' studies using a meta-analysis approach with Hedges' d effect size method. The current meta-analysis shows that organic dairy products contain significantly higher protein, ALA, total omega-3 fatty acid, cis-9,trans-11 conjugated linoleic acid, trans-11 vaccenic acid, eicosapentanoic acid, and docosapentanoic acid than those of conventional types, with cumulative effect size ( ± 95% confidence interval) of 0.56 ± 0.24, 1.74 ± 0.16, 0.84 ± 0.14, 0.68 ± 0.13, 0.51 ± 0.16, 0.42 ± 0.23, and 0.71 ± 0.3, respectively. It is also observed that organic dairy products have significantly (P < 0.001) higher omega-3 to -6 ratio (0.42 vs. 0.23) and Δ9-desaturase index (0.28 vs. 0.27) than the conventional types. The current regulation on organic farming indeed drives organic farms to production of organic dairy products with different nutritional qualities from conventional ones. The differences in feeding regime between conventional and organic dairy production is suspected as the reason behind this evidence. Further identical meta-analysis may be best applicable for summarizing a comparison between conventional and organic foodstuffs for other aspects and food categories.

  2. Dairy farms testing positive for Mycobacterium avium ssp. paratuberculosis have poorer hygiene practices and are less cautious when purchasing cattle than test-negative herds.

    PubMed

    Wolf, R; Barkema, H W; De Buck, J; Orsel, K

    2016-06-01

    Mycobacterium avium ssp. paratuberculosis (MAP), the causative agent of Johne's disease, is present on most dairy farms in Alberta, causing economic losses and presenting a potential public health concern. The objective of this cross-sectional study was to identify risk factors for Alberta dairy herds being MAP-positive based on environmental samples (ES). Risk assessments were conducted and ES were collected on 354 Alberta dairy farms (62% of eligible producers) voluntarily participating in the Alberta Johne's Disease Initiative. In univariate logistic regression, risk factors addressing animal and pen hygiene, as well as the use of feeding equipment to remove manure and manure application on pastures, were all associated with the number of positive ES. Furthermore, based on factor analysis, risk factors were clustered and could be summarized as 4 independent factors: (1) animal, pen, and feeder contamination; (2) shared equipment and pasture contamination; (3) calf diet; and (4) cattle purchase. Using these factor scores as independent variables in multivariate logistic regression models, a 1-unit increase in animal, pen, and feeder contamination resulted in 1.31 times higher odds of having at least 1 positive ES. Furthermore, a 1-unit increase in cattle purchase also resulted in 1.31 times the odds of having at least 1 positive ES. Finally, a 100-cow increase in herd size resulted in an odds ratio of 2.1 for having at least 1 positive ES. In conclusion, cleanliness of animals, pens, and feeders, as well as cattle purchase practices, affected risk of herd infection with MAP. Therefore, improvements in those management practices should be the focus of effective tools to control MAP on dairy farms.

  3. Paratuberculosis: decrease in milk production of German Holstein dairy cows shedding Mycobacterium avium ssp. paratuberculosis depends on within-herd prevalence.

    PubMed

    Donat, K; Soschinka, A; Erhardt, G; Brandt, H R

    2014-05-01

    Paratuberculosis impairs productivity of infected dairy cows because of reduced milk production and fertility and enhanced risk of culling. The magnitude of the milk yield depression in individual cows is influenced by factors such as parity, the stage of the disease and the choice of test used. The objectives of this case-control study were to substantiate the influence of the different levels of the within-herd prevalence (WHP) on individual milk yield of fecal culture (FC)-positive cows (FC+) compared with FC-negative herd-mates (FC-), and to estimate the magnitude of the deviation of the milk yield, milk components and somatic cell count (SCC) in an FC-based study. Of a total of 31 420 cows from 26 Thuringian dairy herds tested for paratuberculosis by FC, a subset of 1382 FC+ and 3245 FC- with milk recording data were selected as cases and controls, respectively. The FC- cows were matched for the same number and stage of lactation (±10 days in milk) as one FC+ from the same herd. Within a mixed model analysis using the fixed effects of Mycobacterium avium ssp. paratuberculosis (MAP) status, lactation number, days in milk, prevalence class of farm and the random effect of farm on milk yield per day (kg), the amount of fat and protein (mg/dl) and lactose (mg/dl) as well as the SCC (1000/ml) were measured. On the basis of least square means, FC+ cows had a lower test-day milk yield (27.7±0.6 kg) compared with FC- (29.0±0.6 kg), as well as a lower milk protein content and a slightly diminished lactose concentration. FC status was not associated with milk fat percentage or milk SCC. In FC+ cows, reduction in milk yield increased with increasing WHP. An interaction of FC status and farm was found for the test-day milk yield, and milk protein percentage, respectively. We conclude that the reduction in milk yield of FC+ cows compared with FC- herd-mates is significantly influenced by farm effects and depends on WHP class. Owners of MAP-positive dairy herds may

  4. Association between caudal fold tuberculin test responses and results of an ELISA for Mycobacterium avium subsp paratuberculosis and mycobacterial culture of feces in tuberculosis-free dairy herds.

    PubMed

    Brito, Barbara P; Aly, Sharif S; Anderson, Randall J; Fossler, Charles P; Garry, Franklyn B; Gardner, Ian A

    2014-03-01

    OBJECTIVE--To evaluate associations between Mycobacterium avium subsp paratuberculosis (MAP) and caudal fold tuberculin (CFT) test results in cattle. DESIGN--Longitudinal and cross-sectional evaluations. ANIMALS--1 California (approx 3,600 cows) and 3 Colorado (approx 640, 1,190, and 1,480 cows) dairy herds considered free of Mycobacterium bovis infection. PROCEDURES--In the California herd, the association between CFT response and MAP status was determined with ELISA and mycobacterial culture of feces within 1 year before and after CFT testing. The association between CFT and MAP status in all herds was modeled with mixed-effects logistic regression. RESULTS--In the California herd, significantly higher odds of being classified as suspect by CFT were found for cows with results of MAP ELISA negative before and positive after CFT testing (OR, 5.6) and cows positive before and after CFT testing (OR, 8.1). Higher odds were found for cows positive for mycobacterial culture of feces before and negative for culture after CFT testing (OR, 4.6) and cows negative for mycobacterial culture of feces before and positive for culture after CFT testing (OR, 13.2). All herds had higher odds of being classified as suspect by CFT testing for cows with positive results for ELISA (OR, 2.9) or mycobacterial culture of feces (OR, 5.0), compared with cows with negative results of the same tests. CONCLUSIONS AND CLINICAL RELEVANCE--A strong association was found between positive MAP test results and being classified as a suspect by CFT testing. Within-herd MAP prevalence may affect specificity of CFT testing for tuberculosis in cattle.

  5. Seroprevalence and risk factors associated to Bovine Herpesvirus 1 (BHV-1) infection in non-vaccinated dairy and dual purpose cattle herds in Ecuador.

    PubMed

    Carbonero, A; Saa, L R; Jara, D V; García-Bocanegra, I; Arenas, A; Borge, C; Perea, A

    2011-06-01

    A cross-sectional study was carried out to determine the seroprevalence and risk factors associated to Bovine Herpesvirus 1 (BHV-1) infection in non-vaccinated dairy and dual purpose cattle herds from Ecuador. A total of 2367 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 environment was filled out in each herd. A commercial indirect ELISA test was used to determine the seropositivity against BHV-1. Generalized Estimating Equations (GEE) model was used to determine risk factors at individual level, including herd as random effect. The individual seroprevalence to BHV-1 in Ecuador was 43.2% (1023/2367; CI(₉₅%): 41.2-45.2%). The herd prevalence was 82.1%; (284/346; CI(₉₅%): 78.1-86.1%) and the intra-herd prevalence ranged from 12.5 to 100% (mean=64.1%). The GEE model showed that animal age (>4 years) (OR: 1.44; CI(₉₅%): 1.18-1.75), BRSV infection (OR: 1.45; CI(₉₅%): 1.09-1.92), altitude over the sea level (≤ 1800 m) (OR: 2.97; CI(₉₅%): 2.1-4.22) and average slope (> 11%) (OR: 1.45; CI(₉₅%): 1.07-1.95) are risk factors associated with BHV-1 infection, while a good cleaning of the facilities (OR: 0.66; CI(₉₅%): 0.44-0.99) was shown to be a protective factor.

  6. Models to Estimate Lactation Curves of Milk Yield and Somatic Cell Count in Dairy Cows at the Herd Level for the Use in Simulations and Predictive Models

    PubMed Central

    Græsbøll, Kaare; Kirkeby, Carsten; Nielsen, Søren Saxmose; Halasa, Tariq; Toft, Nils; Christiansen, Lasse Engbo

    2016-01-01

    Typically, central milk recording data from dairy herds are recorded less than monthly. Over-fitting early in lactation periods is a challenge, which we explored in different ways by reducing the number of parameters needed to describe the milk yield and somatic cell count of individual cows. Furthermore, we investigated how the parameters of lactation models correlate between parities and from dam to offspring. The aim of the study was to provide simple and robust models for cow level milk yield and somatic cell count for fitting to sparse data to parameterize herd- and cow-specific simulation of dairy herds. Data from 610 Danish Holstein herds were used to determine parity traits in milk production regarding milk yield and somatic cell count of individual cows. Parity was stratified in first, second, and third and higher for milk, and first to sixth and higher for somatic cell count. Fitting of herd level parameters allowed for cow level lactation curves with three, two, or one parameters per lactation. Correlations of milk yield and somatic cell count were estimated between lactations and between dam and offspring. The shape of the lactation curves varied markedly between farms. The correlation between lactations for milk yield and somatic cell count was 0.2–0.6 and significant on more than 95% of farms. The variation in the daily milk yield was observed to be a source of variation to the somatic cell count, and the total somatic cell count was less correlated with the milk production than somatic cells per milliliter. A positive correlation was found between relative levels of the total somatic cell count and the milk yield. The variation of lactation and somatic cell count curves between farms highlights the importance of a herd level approach. The one-parameter per cow model using a herd level curve allows for estimating the cow production level from first the recording in the parity, while a two-parameter model requires more recordings for a credible

  7. Effects of season and herd milk volume on somatic cell counts of Florida dairy farms.

    PubMed

    Ferreira, F C; De Vries, A

    2015-06-01

    Dairy farms in Florida produce less milk and milk with higher somatic cell counts (SCC) in the hot and humid summer. This has consequences for the interpretation of average milk quality. The objectives were to describe the associations of bulk tank SCC (BTSCC) with time of the year and the milk volume per farm. Monthly BTSCC and milk volume records from 84% (in 2012; n=1,308) and 77% (in 2013; n=1,200) of the 130 dairy farms in Florida were used. Data were analyzed separately per year. We calculated arithmetic averages of the BTSCC for each farm (ASCCf), each month (ASCCm), and each year (ASCCy). We used the milk volume to calculate a milk-weighted average for each farm (WSCCf), each month (WSCCm), and each year (WSCCy). Period 1 (P1) was defined as February, March, and April, and period 2 (P2) was defined as August, September, and October. These periods generally had the lowest and highest BTSCC throughout the year, respectively. Seasonality was expressed by the P2/P1 ratios of BTSCC and milk volume in both periods. In 2012 and 2013, 72 and 74% of the monthly milk volume observations were <400,000cells/mL. A clear seasonal pattern with lower milk volume and higher ASCCm during P2 was observed for most farms. The averages of the P2/P1 ratio of milk volume were 0.68 and 0.74 in 2012 and 2013. The averages of the P2/P1 ratio of SCC were 1.30 and 1.65 for 2012 and 2013, respectively. The WSCCy was 297,000 cells/mL in 2012 and 274,000 cells/mL in 2013. These values were 13 and 16% lower than the ASCCy in the respective years. In 2012, 82% of the farms shipped milk with a lower WSCCf than their ASCCf. In 2013, 97% of the farms shipped milk with a lower WSCCf than their ASCCf. The difference between a farm's WSCCf and its ASCCf tended to be greater in more-seasonal farms for BTSCC and milk volume. The WSCCm was lower than the ASCCm in every calendar month in both years. Collectively, these results show that the SCC of pooled milk from Florida was substantially lower than

  8. Carbon footprint and land requirement for dairy herd rations: impacts of feed production practices and regional climate variations.

    PubMed

    Henriksson, M; Cederberg, C; Swensson, C

    2014-08-01

    Feed production is a significant source of greenhouse gas (GHG) emissions from dairy production and demands large arable and pasture acreage. This study analysed how regional conditions influence GHG emissions of dairy feed rations in a life cycle perspective, that is the carbon footprint (CF) and the land area required. Factors assessed included regional climate variations, grass/clover silage nutrient quality, feedstuff availability, crop yield and feed losses. Using the Nordic feed evaluation model NorFor, rations were optimised for different phases of lactation, dry and growing periods for older cows, first calvers and heifers by regional feed advisors and combined to annual herd rations. Feed production data at farm level were based on national statistics and studies. CF estimates followed standards for life cycle assessment and used emissions factors provided by IPCC. The functional unit was 'feed consumption to produce 1 kg energy corrected milk (ECM) from a cow with annual milk yield of 9 900 kg ECM including replacement animals and feed losses'. Feed ration CF varied from 417 to 531 g CO2 e/kg ECM. Grass/clover silage contributed more than 50% of total GHG emissions. Use of higher quality silage increased ration CF by up to 5% as a result of an additional cut and increased rates of synthetic N-fertiliser. Domestically produced horse bean (Vicia faba), by-products from the sugar industry and maize silage were included in the rations with the lowest CF, but horse bean significantly increased ration land requirement. Rations required between 1.4 to 2 m2 cropland and 0.1 to 0.2 m2/kg semi-natural grassland per kg ECM and year. Higher yield levels reduced ration total CF. Inclusion of GHG emissions from land use change associated with Brazilian soya feed significantly increased ration CF. Ration CF and land use depended on ration composition, which was highly influenced by the regional availability and production of feedstuffs. The impact of individual

  9. Coxiella burnetii antibody dynamics in heifers born to vaccinated versus non-vaccinated dams in a chronically infected dairy herd.

    PubMed

    Tutusaus, Joan; Garcia-Ispierto, Irina; López-Gatius, Fernando

    2015-09-01

    This study was designed to compare Coxiella burnetii antibody dynamics in heifers born to vaccinated or non-vaccinated dams in a single high-producing dairy herd chronically infected with the bacterium. Antibody dynamics were examined from birth to the postpartum period in replacement heifers (n = 14) born to non-vaccinated dams (n = 7) or to dams that had been vaccinated on gestation days 171-177 (n = 7) and 192-198. Samples of blood, milk, faeces, vaginal fluid, colostrum and cotyledons (the latter two only at parturition) were obtained in the dams over the period from gestation days 171-177 to postpartum days 91-97. Blood samples were used to detect antibodies against C. burnetii and remaining samples for PCR identification of the bacterium. In their calves/heifers, blood samples for antibody determinations were collected from birth to postpartum at the time points 1-7 and 22-28 days and 3, 6 and 12 months of age; 90-96 and 210-216 days of gestation; and 22-28 days postpartum. All calves were born seronegative for C. burnetii. Irrespective of the shedding status of their mothers (7 were C. burnetii shedders), seroconversion occurred after colostrum intake in all calves born to seropositive cows (n = 9) and in two of three vaccinated seronegative dams. Thereafter antibody titres gradually declined and by 6 months of age all calves were seronegative. Seronegativity persisted until their first postpartum period. These findings indicate that cows vaccinated during advanced pregnancy transfer immunity to their calves via the colostrum. Maternal C. burnetii antibodies in calves persisted for three months in calves born both to seronegative vaccinated and seropositive dams.

  10. Effect of dairy farming system, herd, season, parity, and days in milk on modeling of the coagulation, curd firming, and syneresis of bovine milk.

    PubMed

    Bittante, G; Cipolat-Gotet, C; Malchiodi, F; Sturaro, E; Tagliapietra, F; Schiavon, S; Cecchinato, A

    2015-04-01

    The objectives of this study were to characterize the variation in curd firmness model parameters obtained from coagulating bovine milk samples, and to investigate the effects of the dairy system, season, individual farm, and factors related to individual cows (days in milk and parity). Individual milk samples (n = 1,264) were collected during the evening milking of 85 farms representing different environments and farming systems in the northeastern Italian Alps. The dairy herds were classified into 4 farming system categories: traditional system with tied animals (29 herds), modern dairy systems with traditional feeding based on hay and compound feed (30 herds), modern dairy system with total mixed ration (TMR) that included silage as a large proportion of the diet (9 herds), and modern dairy system with silage-free TMR (17 herds). Milk samples were analyzed for milk composition and coagulation properties, and parameters were modeled using curd firmness measures (CFt) collected every 15 s from a lacto-dynamographic analysis of 90 min. When compared with traditional milk coagulation properties (MCP), the curd firming measures showed greater variability and yielded a more accurate description of the milk coagulation process: the model converged for 93.1% of the milk samples, allowing estimation of 4 CFt parameters and 2 derived traits [maximum CF (CF(max)) and time from rennet addition to CF(max) (t(max))] for each sample. The milk samples whose CFt equations did not converge showed longer rennet coagulation times obtained from the model (RCT(eq)) and higher somatic cell score, and came from less-productive cows. Among the sources of variation tested for the CFt parameters, dairy herd system yielded the greatest differences for the contrast between the traditional farm and the 3 modern farms, with the latter showing earlier coagulation and greater instant syneresis rate constant (k(SR)). The use of TMR yielded a greater tmax because of a higher instant curd

  11. Herd and individual animal prevalence of bovine brucellosis with associated risk factors on dairy farms in Haryana and Punjab in India.

    PubMed

    Chand, Puran; Chhabra, Rajesh

    2013-08-01

    Herd and individual animal prevalence along with associated risk factors of bovine brucellosis was assessed on dairy farms located in 22 districts in Haryana and Punjab of India. Examination of 4,580 female animals of 119 dairy farms by Rose Bengal test and enzyme-linked immunosorbent assay revealed that an overall herd prevalence was 65.54% (78/119) and individual animal prevalence was 26.50 % (1,214/4,580). Herd prevalence in Haryana was 62.79% which was not significantly different (P = 0.4208) from Punjab (72.72%). Individual animal prevalence was 34.15% in Punjab which was significantly higher (P < 0.0001) than Haryana (22.34%). Prevalence of brucellosis on dairy farms was detected in 20 of the 22 districts, of which 12 districts were in Haryana and 8 in Punjab. Risk factors such as species of animals, age of animals, herd size, awareness of dairymen for brucellosis, entry of a purchased animals on the farm, abortion on farm, use of calving pens, type of breeding, and type of farming were analyzed. The study indicated that the odds ratio (OR) was significant with risk factors of species (OR = 1.63; 95 %CI = 1.40-1.90; P < 0.0001), age (OR = 0.22; 95%CI = 0.17-0.29; P < 0.0001), awareness of brucellosis among dairymen (OR = 21.65; 95%CI = 2.63-178.04; P = 0.0042), entry of purchased animal on the farm (OR = 9.16; 95%CI = 2.38-35.18; P = 0.0012), abortion in animals (OR = 5.57; 95%CI = 1.92-16.10; P = 0.0015) and on cow farm (OR = 3.43; 95 %CI = 1.33-8.82; P = 0.0105). While the OR was insignificant (P > 0.05) with risk factors of herd size, use of calving pen on farms, type of breeding and on buffalo and mixed type of farms.

  12. Herd- and cow-level risk factors associated with subclinical mastitis in dairy farms from the High Plains of the northern Antioquia, Colombia.

    PubMed

    Ramírez, N F; Keefe, G; Dohoo, I; Sánchez, J; Arroyave, O; Cerón, J; Jaramillo, M; Palacio, L G

    2014-07-01

    Mastitis is the main disease entity affecting dairy farms in the Colombian High Plains of northern Antioquia, Colombia. However, no previous epidemiologic studies have determined the characteristics that increase the risk of infection in this region, where manual milking is still the prevailing system of milking. A 24-mo longitudinal study was designed to identify the predominant mastitis pathogens and important herd- and cow-level risk factors. Monthly visits were made to 37 commercial dairy farms to collect herd- and cow-level data and milk samples. Herd size varied from 6 to 136 cows (mean 37.0, median 29). Herd-level factors included type of milking system (manual or mechanical) and a range of management practices recommended by the National Mastitis Council (Madison, WI) to prevent mastitis. Individual cow-level risk factors included parity, stage of lactation, breed, udder hygiene, and lameness. A logistic regression analysis was used to investigate associations between herd- and cow-level risk factors with the presence of subclinical mastitis and infection caused by Streptococcus agalactiae at the quarter level. A quarter was considered to have subclinical mastitis if it had a positive California Mastitis Test and was subsequently confirmed to have a somatic cell count of ≥200,000 cells/mL. Any cow with one or more quarters with subclinical mastitis was considered to have subclinical mastitis at the cow level. Using 17,622 cow observations, the mean prevalence of subclinical mastitis at the cow level was 37.2% (95% confidence interval: 31.2, 43.3) for the first month and did not substantially change throughout the study. The predominant microorganisms isolated from quarters meeting the subclinical mastitis definition were contagious pathogens, including Strep. agalactiae (34.4%), Corynebacterium spp. (13.2%), and Staphylococcus aureus (8.0%). Significant variables associated with subclinical mastitis risk at the quarter level included being a purebred

  13. Methicillin-resistant Staphylococcus aureus (MRSA) is associated with low within-herd prevalence of intra-mammary infections in dairy cows: Genotyping of isolates.

    PubMed

    Luini, M; Cremonesi, P; Magro, G; Bianchini, V; Minozzi, G; Castiglioni, B; Piccinini, R

    2015-08-05

    Staphylococcus aureus is one of the most common mastitis-causing pathogens worldwide. In the last decade, livestock-associated methicillin-resistant S. aureus (LA-MRSA) infections have been described in several species, included the bovines. Hence, this paper investigates the diffusion of MRSA within Italian dairy herds; the strains were further characterized using a DNA microarray, which detects 330 different sequences, including the methicillin-resistance genes mecA and mecC and SCCmec typing. The analysis of overall patterns allows the assignment to Clonal Complexes (CC). Overall 163 S. aureus isolates, collected from quarter milk samples in 61 herds, were tested. MRSA strains were further processed using spa typing. Fifteen strains (9.2%), isolated in 9 herds (14.75%), carried mecA, but none harboured mecC. MRSA detection was significantly associated (P<0.011) with a within-herd prevalence of S. aureus intra-mammary infections (IMI) ≤5%. Ten MRSA strains were assigned to CC398, the remaining ones to CC97 (n=2), CC1 (n=2) or CC8 (n=1). In 3 herds, MRSA and MSSA co-existed: CC97-MRSA with CC398-MSSA, CC1-MRSA with CC8-MSSA and CC398-MRSA with CC126-MSSA. The results of spa typing showed an overall similar profile of the strains belonging to the same CC: t127-CC1, t1730-CC97, t899 in 8 out of 10 CC398. In the remaining 2 isolates a new spa type, t14644, was identified. The single CC8 was a t3092. The SCCmec cassettes were classified as type IV, type V or type IV/V composite. All or most strains harboured the genes encoding the β-lactamase operon and the tetracycline resistance. Streptogramin resistance gene was related to CC398. Enterotoxin and leukocidin genes were carried only by CC1, CC8 and CC97-MRSA. The persistence of MRSA clones characterized by broader host range, in epidemiologically unrelated areas and in dairy herds with low prevalence of S. aureus IMI, might enhance the risk for adaptation to human species.

  14. 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

  15. Comparative characterization of water extractable organic matter of conventional and organic dairy manure by FT-IR and fluorescence spectroscopies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Organic dairy farming has increased rapidly in recent years. Organic dairy farms have significant differences from conventional counterparts, including fewer imports of protein and energy feeds, and a higher proportion of forage crops in the ration. Although these differences may impact availability...

  16. A retrospective study of the aetiology and temporal distribution of bovine clinical mastitis in smallholder dairy herds in the Dar es Salaam region of Tanzania.

    PubMed

    Kivaria, F M; Noordhuizen, J P T M

    2007-05-01

    A 31-year record-based retrospective study was carried out to determine the aetiology and temporal distribution of bovine clinical mastitis in smallholder dairy herds in the Dar es Salaam region of Tanzania over the period November 1971-December 2002. Laboratory information on 1964 quarter samples from 1365 cows in 281 smallholder dairy herds were retrieved, compiled and studied. Eighty-eight percent of the quarter samples were culture-positive and the predominant mastitis pathogens isolated were Staphylococcus aureus (25.7%), Streptococcus agalactiae (15.4%), Klebsiella pneumoniae (14.3%) and Escherichia coli (14.1%). Other isolates included Pseudomonas aeruginosa (7.5%), Streptococcus dysgalactiae (5.2%) and Streptococcus uberis (4.2%). Contagious mastitis pathogens were isolated from 45.6% of the culture-positive samples, whereas environmental and miscellaneous pathogens were isolated from 48.2% and 5.7%, respectively. Thirty percent of the miscellaneous mastitis pathogens were Candida species. The results demonstrate a steady increase in clinical Candida albicans mastitis. The prevalence of Candida albicans has increased from 1% in 1971 to 17.0% in November 2002. Conversely, despite some fluctuations, the prevalence of Staphylococcus aureus, Streptococcus agalactiae, E. coli and K. pneumoniae remain above 10%. The possible risk factors for these observations are discussed.

  17. Prevalence of Staphylococcus aureus and of methicillin-resistant S. aureus clonal complexes in bulk tank milk from dairy cattle herds in Lombardy Region (Northern Italy).

    PubMed

    Cortimiglia, C; Luini, M; Bianchini, V; Marzagalli, L; Vezzoli, F; Avisani, D; Bertoletti, M; Ianzano, A; Franco, A; Battisti, A

    2016-10-01

    Staphylococcus aureus is the most important causative agent of subclinical mastitis in cattle resulting in reduced milk production and quality. Methicillin-resistant S. aureus (MRSA) strains has a clear zoonotic relevance, especially in the case of occupational exposure. The aim of the study was to evaluate the prevalence of S. aureus and MRSA in bulk tank milk (BTM) from dairy cattle herds in the Lombardy Region (Northern Italy) and to identify the main MRSA circulating genotypes. MRSA strains were characterized by susceptibility testing, multi-locus sequence typing (MLST), spa typing and SCCmec typing. A total 844 BTM samples were analysed and S. aureus and MRSA were detected in 47·2% and 3·8% of dairy herds, respectively. MLST showed that the majority (28/32) of isolates belonged to the typical livestock-associated lineages: ST398, ST97 and ST1. Interestingly, in this study we report for the first time the new ST3211, a single locus variant of ST(CC)22, with the newly described 462 aroE allele. Our study indicates high diffusion of S. aureus mastitis and low, but not negligible, prevalence of MRSA in the considered area, suggesting the need for planning specific control programmes for bovine mastitis caused by S. aureus, especially when MRSA is implicated.

  18. Bulk tank milk surveillance as a measure to detect Coxiella burnetii shedding dairy goat herds in the Netherlands between 2009 and 2014.

    PubMed

    Van den Brom, R; Santman-Berends, I; Luttikholt, S; Moll, L; Van Engelen, E; Vellema, P

    2015-06-01

    In the period from 2005 to 2009, Coxiella burnetii was a cause of abortion waves at 28 dairy goat farms and 2 dairy sheep farms in the Netherlands. Two years after the first abortion waves, a large human Q fever outbreak started mainly in the same region, and aborting small ruminants were regarded as most probable source. To distinguish between infected and noninfected herds, a surveillance program started in October 2009, based on PCR testing of bulk tank milk (BTM) samples, which had never been described before. The aim of this study was to analyze the effectiveness of this surveillance program and to evaluate both the effect of culling of pregnant dairy goats on positive farms and of vaccination on BTM results. Bulk tank milk samples were tested for C. burnetii DNA using a real-time PCR, and results were analyzed in relation to vaccination, culling, and notifiable (officially reported to government) C. burnetii abortion records. In spring and autumn, BTM samples were also tested for antibodies using an ELISA, and results were evaluated in relation to the compulsory vaccination campaign. Between October 2009 and April 2014, 1,660 (5.6%) out of 29,875 BTM samples from 401 dairy goat farms tested positive for C. burnetii DNA. The percentage of positive samples dropped from 20.5% in 2009 to 0.3% in 2014. In a multivariable model, significantly higher odds of being PCR positive in the BTM surveillance program were found in farms of which all pregnant dairy goats were culled. Additionally, the risk for C. burnetii BTM PCR positivity significantly decreased after multiple vaccinations. Bulk tank milk ELISA results were significantly higher after vaccination than before. The ELISA results were higher after multiple vaccinations compared with a single vaccination, and ELISA results on officially declared infected farms were significantly higher compared with noninfected farms. In conclusion, BTM surveillance is an effective and useful tool to detect C. burnetii shedding

  19. Prevalence and antibiotic susceptibility of coagulase-negative Staphylococcus species from bovine subclinical mastitis in dairy herds in the central region of Argentina.

    PubMed

    Raspanti, Claudia G; Bonetto, Cesar C; Vissio, Claudina; Pellegrino, Matías S; Reinoso, Elina B; Dieser, Silvana A; Bogni, Cristina I; Larriestra, Alejandro J; Odierno, Liliana M

    2016-01-01

    Coagulase-negative staphylococci (CNS) are a common cause of bovine subclinical mastitis (SCM). The prevalence of CNS species causing SCM identified by genotyping varies among countries. Overall, the antimicrobial resistance in this group of organisms is increasing worldwide; however, little information exists about a CNS species resistant to antibiotics. The aim of the present study was to genotypically characterize CNS at species level and to determine the prevalence and antibiotic resistance profiles of CNS species isolated from bovine SCM in 51 dairy herds located in the central region of the province of Cordoba, Argentina. In this study, we identified 219 CNS isolates at species level by PCR-restriction fragment length polymorphism of the groEL gene. Staphylococcus chromogenes (46.6%) and Staphylococcus haemolyticus (32%) were the most prevalent species. A minimum of three different CNS species were present in 41.2% of the herds. S. chromogenes was isolated from most of the herds (86.3%), whereas S. haemolyticus was isolated from 66.7% of them. The broth microdilution method was used to test in vitro antimicrobial susceptibility. Resistance to a single compound or two related compounds was expressed in 43.8% of the isolates. S. chromogenes and S. haemolyticus showed a very high proportion of isolates resistant to penicillin. Resistance to two or more non-related antimicrobials was found in 30.6% of all CNS. S. haemolyticus exhibited a higher frequency of resistance to two or more non-related antimicrobials than S. chromogenes.

  20. Phylogenetic analyses of typical bovine rotavirus genotypes G6, G10, P[5] and P[11] circulating in Argentinean beef and dairy herds.

    PubMed

    Badaracco, A; Garaicoechea, L; Matthijnssens, J; Louge Uriarte, E; Odeón, A; Bilbao, G; Fernandez, F; Parra, G I; Parreño, V

    2013-08-01

    Group A rotavirus (RVA) is one of the main causes of neonatal calf diarrhea worldwide. RVA strains affecting Argentinean cattle mainly possess combinations of the G6, G10, P[5] and P[11] genotypes. To determine RVA diversity among Argentinean cattle, representative bovine RVA strains detected in diarrheic calves were selected from a survey conducted during 1997-2009. The survey covered the main livestock regions of the country from dairy and beef herds. Different phylogenetic approaches were used to investigate the genetic evolution of RVA strains belonging to the prevalent genotypes. The nucleotide phylogenetic tree showed that all genotypes studied could be divided into several lineages. Argentinean bovine RVA strains were distributed across multiple lineages and most of them were distinct from the lineage containing the vaccine strains. Only the aminoacid phylogenetic tree of G6 RVA strains maintained the same lineages as observed at the nucleotide level, whereas a different clustering pattern was observed for the aminoacid phylogenetic trees of G10, P[5] and P[11] suggesting that the strains are more closely related at the aminoacid level than G6 strains. Association between P[5] and G6(IV), prevalent in beef herd, and between P[11] and G6(III) or G10 (VI and V), prevalent in dairy herds, were found. In addition, Argentinean G6(III), G10, P[5] and P[11] bovine RVA strains grouped together with human strains, highlighting their potential for zoonotic transmission. Phylogenetic studies of RVA circulating in animals raised for consumption and in close contact with humans, such as cattle, contribute to a better understanding of the epidemiology of the RVA infection and evolution.

  1. A prospective study of the effect of Neospora caninum and BVDV infections on bovine abortions in a dairy herd in Arequipa, Peru.

    PubMed

    Ståhl, K; Björkman, C; Emanuelson, U; Rivera, H; Zelada, A; Moreno-López, J

    2006-08-17

    We used a prospective seroepidemiological approach to investigate endemic abortion in a dairy herd in Arequipa, Peru, and its association with Neospora caninum and bovine viral-diarrhoea virus (BVDV) infections. Between January 2002 and March 2004, 1094 pregnancies were confirmed in 538 cows. Of these, 137 pregnancies (13%) in 121 cows ended in abortion. The serological status to N. caninum was assessed using a single serological screening, whereas BVDV status was assessed at the herd level through consecutive samplings of young stock. Cox proportional-hazards models were used to estimate the effect of N. caninum and BVDV on the hazard of early (between day 42 and day 100 in gestation), and late (after day 100) abortions, respectively. Serological status to N. caninum was included as a dichotomous variable, and the effect of BVDV estimated at the herd level, as a time-dependent seasonal effect. Because data from repeated pregnancies were included, we considered possible lack of independence between observations and included frailty effects into the models. Our models also considered the possible confounding by parity and animal origin. Only multiparity was associated with the hazard of early abortion (HR=2.8 compared to nulliparous heifers). N. caninum seropositivity significantly affected the hazard of late abortion, but interacted with parity. The HRs for Neospora-positive animals were 6.4, 3.7 and 1.9, respectively, for nulliparous heifers, first-lactation cows and multiparous cows. Evidence of BVDV circulating (or not) among the young stock was not associated with abortions, but few cows in this herd were susceptible to incident infection.

  2. The impact of 3 strategies for incorporating polled genetics into a dairy cattle breeding program on the overall herd genetic merit.

    PubMed

    Spurlock, D M; Stock, M L; Coetzee, J F

    2014-01-01

    Dehorning in cattle has been associated with behavioral, physiological, and neuroendocrine responses indicative of pain. Unaddressed, the pain associated with a routine production procedure could contribute to a negative public perception of livestock production practices. Alternative considerations of dehorning include the selection of polled cattle within herds, thereby avoiding pain and production loss. As polledness results from an autosomal dominant pattern of inheritance, genetic selection for polled cattle could reduce the prevalence of the horned trait. Herein we discuss 3 strategies to incorporate polled genetics into a cow herd and the estimated impact on the overall genetic merit of the herd. Furthermore, the availability and genetic merit of polled artificial insemination bulls in the United States is summarized. Both Holstein and Jersey dairy bulls registered with the National Association of Animal Breeders from December 2010 through April 2013 were queried. Polled bulls were identified as either being homozygous (PP) or heterozygous (Pp) and the average net merit (NM) predicted transmitting ability (PTA) of each sire group was calculated. The percentage of polled calves born each year over a 10-yr period was calculated for the following 3 scenarios: (A) various percentages of horned cows were randomly mated to Pp bulls, (B) various percentages of horned cows were preferentially mated to Pp bulls, and (C) horned cows were selectively mated to PP bulls, heterozygous cows to Pp bulls, and homozygous polled cows to horned bulls. Additionally, the change in NM PTA of the cow herd was calculated over the same period. The highest percentage of polled animals (87%) was achieved in scenario C. An evaluation of the herd NM PTA highlights the trade-offs associated with increasing polled genetics. Given the current genetic merit of horned and polled bulls, increasing the percentage of polled calves will decrease the NM PTA in Holstein, but may have minimal impact

  3. Estimation of the time of seroconversion to the New Jersey serotype of vesicular stomatitis virus in sentinel cattle of dairy herds located at high and low elevations in southern Mexico

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To estimate time to seroconversion to vesicular stomatitis 1 New Jersey virus (VSNJV) in sentinel cattle in southern Mexico, ninety-two sentinel cattle in four free-ranging dairy herds at high- (=500 mts) and low-elevation (<500 mts) locations in southern Mexico were studied. A prospective cohort s...

  4. Associations of herd- and cow-level factors, cow lying behavior, and risk of elevated somatic cell count in free-stall housed lactating dairy cows.

    PubMed

    Watters, M E Alexandrea; Meijer, Karin M A; Barkema, Herman W; Leslie, Kenneth E; von Keyserlingk, Marina A G; Devries, Trevor J

    2013-09-01

    Recent evidence suggests that the risk of intramammary infection in dairy cows is related to lying patterns. The objectives of this study were to quantify the standing and lying behavior of dairy cows milked 3×/d, determine the cow- and herd-level factors associated with these behaviors, and relate these findings to the risk of an elevated somatic cell count (SCC). Five commercial free-stall dairy herds in Eastern Ontario, milking 3×/d, were enrolled in a longitudinal study. Forty Holstein-Friesian cows/herd were randomly selected as focal animals based on days in milk (<200 d) and SCC (<100,000 cells/mL). Farms were followed for 4, 5-week periods. Individual-cow SCC was recorded at the beginning of each period and end of the final period. Elevated SCC (eSCC) was used as an indicator of subclinical mastitis. A new incident eSCC was defined as an individual cow that started the period with a SCC <100,000 cells/mL but whose next SCC exceeded 200,000 cells/mL. Lying behavior was recorded 5d after each milk sampling using data loggers. For these 5d, individual milking times and feeding times were also recorded. On d1 of each recording period 2 trained observers scored focal cows for hygiene and lameness. Throughout the course of the study, cows averaged 11.2h/d of lying time, split into 8.6 lying bouts/d that were on average 84.6 min in length. Later lactation cows had longer daily lying times that were split into fewer lying bouts of longer duration than cows earlier in lactation. Lame cows had longer daily lying times and lying bout durations than non-lame cows. Cows with greater milk yield had lower lying times than lower producing cows. Average post-milking standing time across the study herds was 103 min. Manipulation of feed (feed delivery or push-up) by the stockperson, in the hour before milking or shortly thereafter, resulted in the longest post-milking standing times. Over the study period, 48 new eSCC were detected, resulting in a mean herd incidence rate

  5. Comparing risk in conventional and organic dairy farming in the Netherlands: an empirical analysis.

    PubMed

    Berentsen, P B M; Kovacs, K; van Asseldonk, M A P M

    2012-07-01

    This study was undertaken to contribute to the understanding of why most dairy farmers do not convert to organic farming. Therefore, the objective of this research was to assess and compare risks for conventional and organic farming in the Netherlands with respect to gross margin and the underlying price and production variables. To investigate the risk factors a farm accountancy database was used containing panel data from both conventional and organic representative Dutch dairy farms (2001-2007). Variables with regard to price and production risk were identified using a gross margin analysis scheme. Price risk variables were milk price and concentrate price. The main production risk variables were milk yield per cow, roughage yield per hectare, and veterinary costs per cow. To assess risk, an error component implicit detrending method was applied and the resulting detrended standard deviations were compared between conventional and organic farms. Results indicate that the risk included in the gross margin per cow is significantly higher in organic farming. This is caused by both higher price and production risks. Price risks are significantly higher in organic farming for both milk price and concentrate price. With regard to production risk, only milk yield per cow poses a significantly higher risk in organic farming.

  6. Farm Management in Organic and Conventional Dairy Production Systems Based on Pasture in Southern Brazil and Its Consequences on Production and Milk Quality

    PubMed Central

    Kuhnen, Shirley; Stibuski, Rudinei Butka; Honorato, Luciana Aparecida; Pinheiro Machado Filho, Luiz Carlos

    2015-01-01

    Simple Summary This study provides the characteristics of the conventional high input (C-HI), conventional low input (C-LI), and organic low input (O-LI) pasture-based production systems used in Southern Brazil, and its consequences on production and milk quality. C-HI farms had larger farms and herds, annual pasture with higher inputs and milk yield, whereas O-LI had smaller farms and herds, perennial pastures with lowest input and milk yields; C-LI was in between. O-LI farms may contribute to eco-system services, but low milk yield is a major concern. Hygienic and microbiological milk quality was poor for all farms and needs to be improved. Abstract Pasture-based dairy production is used widely on family dairy farms in Southern Brazil. This study investigates conventional high input (C-HI), conventional low input (C-LI), and organic low input (O-LI) pasture-based systems and their effects on quantity and quality of the milk produced. We conducted technical site visits and interviews monthly over one year on 24 family farms (n = 8 per type). C-HI farms had the greatest total area (28.9 ha), greatest percentage of area with annual pasture (38.7%), largest number of lactating animals (26.2) and greatest milk yield per cow (22.8 kg·day−1). O-LI farms had the largest perennial pasture area (52.3%), with the greatest botanical richness during all seasons. Area of perennial pasture was positively correlated with number of species consumed by the animals (R2 = 0.74). Milk from O-LI farms had higher levels of fat and total solids only during the winter. Hygienic and microbiological quality of the milk was poor for all farms and need to be improved. C-HI farms had high milk yield related to high input, C-LI had intermediate characteristics and O-LI utilized a year round perennial pasture as a strategy to diminish the use of supplements in animal diets, which is an important aspect in ensuring production sustainability. PMID:26479369

  7. 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

  8. 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

  9. Studies on BVD involving establishment of sentinel calves and assessment of herd immunity in a large dairy farm in Saudi Arabia.

    PubMed

    Abu Elzein, Eltayb; Alkhalyifa, Mofeed

    2012-03-01

    Little information is published, so far, regarding bovine viral diarrhea (BVD) in Saudi Arabia and the Gulf region. This study is the first of its kind in the country. Its aim was to explore the BVD situation in a large dairy farm, which has been experiencing reproduction problems suggestive of BVD virus infection, albeit the practice of routine vaccination. The study took two pathways; the first involved establishment of a cohort of sentinel calves so as: (a) to note the BVD virus activity in the farm by following the time lapse and pattern for waning of the maternally derived antibodies and detection of any subsequent seroconversion and (b) to look for any clinical signs suggestive of BVD virus infection in these calves. The second pathway was to assess the level of herd immunity in the different age groups of lactating cows and maiden heifers. The obtained results were discussed, and control strategies were outlined.

  10. 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.

  11. Molecular Detection and Sensitivity to Antibiotics and Bacteriocins of Pathogens Isolated from Bovine Mastitis in Family Dairy Herds of Central Mexico

    PubMed Central

    León-Galván, Ma. Fabiola; Barboza-Corona, José E.; Lechuga-Arana, A. Arianna; Valencia-Posadas, Mauricio; Aguayo, Daniel D.; Cedillo-Pelaez, Carlos; Martínez-Ortega, Erika A.; Gutierrez-Chavez, Abner J.

    2015-01-01

    Thirty-two farms (n = 535 cows) located in the state of Guanajuato, Mexico, were sampled. Pathogens from bovine subclinical mastitis (SCM) and clinical mastitis (CLM) were identified by 16S rDNA and the sensitivity to both antibiotics and bacteriocins of Bacillus thuringiensis was tested. Forty-six milk samples were selected for their positive California Mastitis Test (CMT) (≥3) and any abnormality in the udder or milk. The frequency of SCM and CLM was 39.1% and 9.3%, respectively. Averages for test day milk yield (MY), lactation number (LN), herd size (HS), and number of days in milk (DM) were 20.6 kg, 2.8 lactations, 16.7 animals, and 164.1 days, respectively. MY was dependent on dairy herd (DH), LN, HS, and DM (P < 0.01), and correlations between udder quarters from the CMT were around 0.49 (P < 0.01). Coagulase-negative staphylococci were mainly identified, as well as Staphylococcus aureus, Streptococcus uberis, Brevibacterium stationis, B. conglomeratum, and Staphylococcus agnetis. Bacterial isolates were resistant to penicillin, clindamycin, ampicillin, and cefotaxime. Bacteriocins synthesized by Bacillus thuringiensis inhibited the growth of multiantibiotic resistance bacteria such as S. agnetis, S. equorum, Streptococcus uberis, Brevibacterium stationis, and Brachybacterium conglomeratum, but they were not active against S. sciuri, a microorganism that showed an 84% resistance to antibiotics tested in this study. PMID:25815326

  12. Molecular detection and sensitivity to antibiotics and bacteriocins of pathogens isolated from bovine mastitis in family dairy herds of central Mexico.

    PubMed

    León-Galván, Ma Fabiola; Barboza-Corona, José E; Lechuga-Arana, A Arianna; Valencia-Posadas, Mauricio; Aguayo, Daniel D; Cedillo-Pelaez, Carlos; Martínez-Ortega, Erika A; Gutierrez-Chavez, Abner J

    2015-01-01

    Thirty-two farms (n = 535 cows) located in the state of Guanajuato, Mexico, were sampled. Pathogens from bovine subclinical mastitis (SCM) and clinical mastitis (CLM) were identified by 16S rDNA and the sensitivity to both antibiotics and bacteriocins of Bacillus thuringiensis was tested. Forty-six milk samples were selected for their positive California Mastitis Test (CMT) (≥3) and any abnormality in the udder or milk. The frequency of SCM and CLM was 39.1% and 9.3%, respectively. Averages for test day milk yield (MY), lactation number (LN), herd size (HS), and number of days in milk (DM) were 20.6 kg, 2.8 lactations, 16.7 animals, and 164.1 days, respectively. MY was dependent on dairy herd (DH), LN, HS, and DM (P < 0.01), and correlations between udder quarters from the CMT were around 0.49 (P < 0.01). Coagulase-negative staphylococci were mainly identified, as well as Staphylococcus aureus, Streptococcus uberis, Brevibacterium stationis, B. conglomeratum, and Staphylococcus agnetis. Bacterial isolates were resistant to penicillin, clindamycin, ampicillin, and cefotaxime. Bacteriocins synthesized by Bacillus thuringiensis inhibited the growth of multiantibiotic resistance bacteria such as S. agnetis, S. equorum, Streptococcus uberis, Brevibacterium stationis, and Brachybacterium conglomeratum, but they were not active against S. sciuri, a microorganism that showed an 84% resistance to antibiotics tested in this study.

  13. [Effects of a two-year dairy herd health management programme on udder health, use of antibiotics and longevity].

    PubMed

    Ivemeyer, S; Maeschli, A; Walkenhorst, M; Klocke, P; Heil, F; Oser, S; Notz, C

    2008-10-01

    Since 2003, the Research Institute of Organic Agriculture (FiBL) is realizing a herd health management programme ("pro-Q" project) focussing on udder health. The objectives of the project are: (1) to reduce antibiotic mastitis treatments, (2) to optimise udder health and (3) to improve longevity, measured as averaged number of herd lactations. The farms get expert advice in prevention and treatment on herd- and animal-level. After 2 years, treatment recordings of the 65 investigated farms showed that antibiotic mastitis therapies were reduced from 38 to 26 treatments per 100 cows and year (equals a reduction of 32%). Lactation numbers of the herds increased significantly by 0.2 lactations from 3.3 to 3.5 lactations per cow. Udder health remained constant over all farms during 2 years: theoretical bulk milk cell counts averaged constantly at around 180000 cells/ml. Improvement of udder health on farm level was significantly influenced by higher somatic cell count when the project started and enhanced by farmer's motivation and farm-veterinarians' commitment to the project.

  14. Use of a staphylococcal vaccine to reduce prevalence of mastitis and lower somatic cell counts in a registered Saanen dairy goat herd.

    PubMed

    Kautz, F M; Nickerson, S C; Ely, L O

    2014-08-01

    This investigation evaluated the efficacy of a bacterin in reducing the prevalence of staphylococcal mastitis and somatic cell counts (SCC) in a dairy goat herd. Does were vaccinated or left as controls, and the levels of mastitis and SCC monitored over 18 months. Staphylococcus caprae (42.5%), S. xylosus (15.1%), and S. simulans (10.0%) were the predominant causes of intramammary infections (IMI). The infection rate was 1.64 IMI/doe among vaccinates, which tended to be lower (P < 0.12) than controls (2.67 IMI/doe). The spontaneous cure rate of IMI after immunization was 1.28 cures/doe in vaccinates, which was higher than controls (0.6 cures/doe; P < 0.043). Average SCC of milk samples from vaccinates tended to be lower than that of controls (1274 × 10(3)/ml vs. 1529 × 10(3)/ml, respectively) (P < 0.10). Results support the continued study of mastitis vaccines for use in managing staphylococcal mastitis and SCC in dairy goats.

  15. Udder infections with Staphylococcus aureus, Streptococcus dysgalactiae, and Streptococcus uberis at calving in dairy herds with suboptimal udder health.

    PubMed

    Lundberg, Å; Nyman, A-K; Aspán, A; Börjesson, S; Unnerstad, H Ericsson; Waller, K Persson

    2016-03-01

    Udder infections with Staphylococcus aureus, Streptococcus dysgalactiae, and Streptococcus uberis are common causes of bovine mastitis. To study these pathogens in early lactation, a 12-mo longitudinal, observational study was carried out in 13 herds with suboptimal udder health. The aims of the study were to investigate the occurrence of these pathogens and to identify if presence of the 3 pathogens, and of genotypes within the pathogens, differed with respect to herd, season, and parity. Quarter milk samples, collected at calving and 4 d in milk (DIM), were cultured for the 3 pathogens. Genotyping of staphylococcal and streptococcal isolates was performed using spa typing and pulsed-field gel electrophoresis, respectively. For each of the 3 pathogens, cows with an udder infection at calving or 4 DIM were allocated to 1 of 4 infection types: cleared (pathogen present only at calving), persistent (pathogen present in the same quarter at calving and 4 DIM), new (pathogen present only at 4 DIM), or cleared/new (pathogen present in 1 quarter at calving and in another quarter at 4 DIM). Associations between season or parity and overall occurrence of pathogens or infection types were determined using univariable mixed-effect logistic-regression models and the Fisher's exact test, respectively. The most commonly occurring pathogen was Staph. aureus, followed by Strep. dysgalactiae and Strep. uberis. Persistent infections were the most common infection type among Staph. aureus-infected cows, whereas cleared infections were the most common among Strep. dysgalactiae- and Strep. uberis-positive cows. The proportion of cows with persistent Staph. aureus infections and the proportion of cows having a Strep. uberis infection at calving or 4 DIM were higher in the multiparous cows than in primiparous cows. Infections with Strep. dysgalactiae were less common during the early housing season than during the late housing or pasture seasons, whereas persistent Strep. uberis

  16. An intra-laboratory cultural and real-time PCR method comparison and evaluation for the detection of subclinical paratuberculosis in dairy herds.

    PubMed

    Heuvelink, Annet; Hassan, Abdulwahed Ahmed; van Weering, Hilmar; van Engelen, Erik; Bülte, Michael; Akineden, Ömer

    2016-12-17

    Mycobacterium avium subsp. paratuberculosis (MAP) is a vigorous microorganism which causes incurable chronic enteritis, Johne's disease (JD) in cattle. A target of control programmes for JD is to accurately detect MAP-infected cattle early to reduce disease transmission. The present study evaluated the efficacy of two different cultural procedures and a TaqMan real-time PCR assay for detection of subclinical paratuberculosis in dairy herds. Therefore, sixty-one faecal samples were collected from two Dutch dairy herds (n = 40 and n = 21, respectively) which were known to be MAP-ELISA positive. All individual samples were assessed using two different cultural protocols in two different laboratories. The first cultural protocol (first laboratory) included a decontamination step with 0.75% hexadecylpyridinium chloride (HPC) followed by inoculation on Herrold's egg yolk media (HEYM). The second protocol (second laboratory) comprised of a decontamination step using 4% NaOH and malachite green-oxalic acid followed by inoculation on two media, HEYM and in parallel on modified Löwenstein-Jensen media (mLJ). For the TaqMan real-time PCR assay, all faecal samples were tested in two different laboratories using TaqMan® MAP (Johne's) reagents (Life Technologies). The cultural procedures revealed positive reactions in 1.64% of the samples for cultivation protocol 1 and 6.56 and 8.20% of the samples for cultivation protocol 2, respectively. The results of the TaqMan real-time PCR performed in two different laboratories yielded 13.11 and 19.76% positive reaction. The kappa test showed proportional agreement 0.54 between the mLJ media (second laboratory) and TaqMan® real-time PCR method (second laboratory). In conclusion, the TaqMan real-time PCR could be a strongly useful and efficient assay for the detection of subclinical paratuberculosis in dairy cattle leading to an improvement in the efficiency of MAP control strategies.

  17. Longitudinal Study of Two Irish Dairy Herds: Low Numbers of Shiga Toxin-Producing Escherichia coli O157 and O26 Super-Shedders Identified

    PubMed Central

    Murphy, Brenda P.; McCabe, Evonne; Murphy, Mary; Buckley, James F.; Crowley, Dan; Fanning, Séamus; Duffy, Geraldine

    2016-01-01

    A 12-month longitudinal study was undertaken on two dairy herds to ascertain the Shiga-toxin producing Escherichia coli (STEC) O157 and O26 shedding status of the animals and its impact (if any) on raw milk. Cattle are a recognized reservoir for these organisms with associated public health and environmental implications. Animals shedding E. coli O157 at >10,000 CFU/g of feces have been deemed super-shedders. There is a gap in the knowledge regarding super-shedding of other STEC serogroups. A cohort of 40 lactating cows from herds previously identified as positive for STEC in a national surveillance project were sampled every second month between August, 2013 and July, 2014. Metadata on any potential super-shedders was documented including, e.g., age of the animal, number of lactations and days in lactation, nutritional condition, somatic cell count and content of protein in milk to assess if any were associated with risk factors for super-shedding. Recto-anal mucosal swabs (RAMS), raw milk, milk filters, and water samples were procured for each herd. The swabs were examined for E. coli O157 and O26 using a quantitative real time PCR method. Counts (CFU swab-1) were obtained from a standard calibration curve that related real-time PCR cycle threshold (Ct) values against the initial concentration of O157 or O26 in the samples. Results from Farm A: 305 animals were analyzed; 15 E. coli O157 (5%) were recovered, 13 were denoted STEC encoding either stx1 and/or stx2 virulence genes and 5 (2%) STEC O26 were recovered. One super-shedder was identified shedding STEC O26 (stx1&2). Farm B: 224 animals were analyzed; eight E. coli O157 (3.5%) were recovered (seven were STEC) and 9 (4%) STEC O26 were recovered. Three super-shedders were identified, one was shedding STEC O157 (stx2) and two STEC O26 (stx2). Three encoded the adhering and effacement gene (eae) and one isolate additionally encoded the haemolysin gene (hlyA). All four super-shedders were only super-shedding once

  18. Management, feeding, production, reproduction and udder health on organic and conventional Swiss dairy farms.

    PubMed

    Roesch, M; Doherr, M G; Blum, J W

    2006-08-01

    Organic dairy farms (OP; n=60) and conventional dairy farms (integrated production, IP; n=60), matched in size, location, and agricultural zone (altitude), were studied for possible differences in management, feeding, production, reproduction and udder health. OP and IP farms were similar in size (17.7 and 16.9 ha), milk quota (65900 and 70,000 kg/year), cow number (14 and 15), cow age (5.3 and 5.2 years), housing of cows of the Simmental x Red Holstein or Holstein breeds (87 and 75%; 45 and 60%), but differed significantly with respect to loose housing systems (18 and 7%), outside paddocks (98 and 75%), energy-corrected 305-d milk yield (5,695 and 6,059 kg), milk protein content (31.8 and 32.7 g/kg), use of bucket milking systems (73 and 33%), observance of regular (12-h) milking intervals (47 and 68%), routine application of the California-Mastitis-Test (10 and 28%), teat dipping after milking (25 and 43%) and blanket dry cow treatments (0 and 45%). Milk somatic cell counts on OP and IP farms (119 000 and 117,000/mL) and reproduction data were similar and there were no significant differences between OP and IP farms as concerns available feeds, planning and management of feeding. Alternative veterinary treatments were used more often on OP than IP farms (55 and 17%). Main causes for cow replacements on OP and IP farms were fertility disorders (both 45%), age (40 and 42%), sale (30 and 37%) and udder health (35 and 13%). Between OP and IP Swiss dairy farms thus relatively few larger differences were found.

  19. Treatment practices and quantification of antimicrobial drug usage in conventional and organic dairy farms in Wisconsin.

    PubMed

    Pol, M; Ruegg, P L

    2007-01-01

    The objective of this study was to develop a method to quantify antimicrobial drug usage and treatment practices on conventional and organic dairy farms that had been recruited to represent a broad spectrum of potential exposure to antimicrobial drugs. Data on disease prevalence and treatment practices of organic (n = 20) and conventional (n = 20) farms were obtained during a farm visit using a survey instrument. A standardized estimate of antimicrobial drug usage was developed using a defined daily dose (DDD) of selected compounds. Density of antimicrobial drug usage was expressed as the number of DDD per adult cow per year. Differences in prevalence and management of selected diseases between conventional and organic farms were identified. The overall estimated prevalence of selected diseases was greater for conventional farms compared with organic farms. Organic farmers reported use of a variety of nonantimicrobial compounds for treatment and prevention of disease. Conventional farmers reported that penicillin was the compound most commonly used for dry cow therapy and cephapirin was most commonly used for treatment of clinical mastitis. On conventional farms, the estimated overall exposure to antimicrobial drugs was 5.43 DDD per cow per year composed of 3.58 and 1.85 DDD of intramammary and parenteral antimicrobial drugs, respectively. Of total intramammary antimicrobial drug usage, treatment of clinical mastitis contributed 2.02 DDD compared with 1.56 DDD attributed to the use of dry cow therapy. Of total parenteral treatments, the distribution of exposure was 0.52 (dry cow therapy), 1.43 (clinical mastitis treatment), 0.39 (treatment of foot disease), 0.14 (treatment of respiratory disease), and 0.32 (treatment of metritis) DDD. For treatments of foot infections (0.33 DDD), respiratory infections (0.07 DDD), and metritis (0.19 DDD), the mean density of ceftiofur usage was significantly greater compared with other compounds.

  20. Longitudinal data collection of Mycobacterium avium subspecies Paratuberculosis infections in dairy herds. Collection and use of observational data

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Longitudinal infection data on Mycobacterium avium subspecies paratuberculosis (MAP) was collected on three dairy farms in Northeastern United States during approximately 10 years. Precise data on animal characteristics and animal location within farm were collected on these farms. Cows were followe...

  1. Dynamics of Escherichia coli virulence factors in dairy herds and farm environments in a longitudinal study in the United States

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dairy farms are known reservoirs of enteropathogenic E. coli (EPEC). EPEC, or the virulence factors associated with pathogenicity, have been detected in manure, milk, and the farm environment. It is unclear which farm compartments are reservoirs for EPEC and their long-term dynamics are not describe...

  2. Comparative analysis of the diversity of aerobic spore-forming bacteria in raw milk from organic and conventional dairy farms.

    PubMed

    Coorevits, An; De Jonghe, Valerie; Vandroemme, Joachim; Reekmans, Rieka; Heyrman, Jeroen; Messens, Winy; De Vos, Paul; Heyndrickx, Marc

    2008-06-01

    Bacterial contamination of raw milk can originate from different sources: air, milking equipment, feed, soil, faeces and grass. It is hypothesized that differences in feeding and housing strategies of cows may influence the microbial quality of milk. This assumption was investigated through comparison of the aerobic spore-forming flora in milk from organic and conventional dairy farms. Laboratory pasteurized milk samples from five conventional and five organic dairy farms, sampled in late summer/autumn and in winter, were plated on a standard medium and two differential media, one screening for phospholipolytic and the other for proteolytic activity of bacteria. Almost 930 isolates were obtained of which 898 could be screened via fatty acid methyl ester analysis. Representative isolates were further analysed using 16S rRNA gene sequencing and (GTG)(5)-PCR. The majority of aerobic spore-formers in milk belonged to the genus Bacillus and showed at least 97% 16S rRNA gene sequence similarity with type strains of Bacillus licheniformis, Bacillus pumilus, Bacillus circulans, Bacillus subtilis and with type strains of species belonging to the Bacillus cereus group. About 7% of all isolates may belong to possibly new spore-forming taxa. Although the overall diversity of aerobic spore-forming bacteria in milk from organic vs. conventional dairy farms was highly similar, some differences between both were observed: (i) a relatively higher number of thermotolerant organisms in milk from conventional dairy farms compared to organic farms (41.2% vs. 25.9%), and (ii) a relatively higher number of B. cereus group organisms in milk from organic (81.3%) and Ureibacillus thermosphaericus in milk from conventional (85.7%) dairy farms. One of these differences, the higher occurrence of B. cereus group organisms in milk from organic dairy farms, may be linked to differences in housing strategy between the two types of dairy farming. However, no plausible clarification was found for

  3. A Vegetation Index qualifying pasture edges is related to Ixodes ricinus density and to Babesia divergens seroprevalence in dairy cattle herds.

    PubMed

    Agoulon, Albert; Malandrin, Laurence; Lepigeon, Florent; Vénisse, Maxime; Bonnet, Sarah; Becker, Claire A M; Hoch, Thierry; Bastian, Suzanne; Plantard, Olivier; Beaudeau, François

    2012-04-30

    Babesia divergens, transmitted by the tick Ixodes ricinus, is the main agent of bovine piroplasmosis in France. This Apicomplexa often is present in asymptomatic carriers; however, clinical cases are rare. While numerous factors are known to influence tick density, no risk factor of contact with B. divergens has been identified for cattle. Our study aimed to explore whether a Vegetation Index could serve as an indirect indicator of within-herd B. divergens seroprevalence. In February 2007, blood samples were taken from all of the cows in 19 dairy cattle herds in Western France and IFAT serology was performed individually to measure B. divergens seroprevalence. The following spring, I. ricinus nymphs were collected by drag sampling along transects on the vegetation of each farm's pasture perimeters. Tick density was related significantly to a Vegetation Index (V.I., ranging from 1 to 5) that took into account the abundance of trees and bushes on the edge of pastures: most ticks (57%) were found in transects with the highest V.I. (covering 15% of the explored surface in the study area). At the farm level, the proportion of transects presenting I. ricinus nymphs was significantly related to B. divergens seroprevalence: the farms with more than 15% of transects with I. ricinus had a significantly higher risk of high seroprevalence. The proportion of pasture perimeters where the V.I.=5 also was significantly related to B. divergens seroprevalence: the farms where more than 20% of transects had a V.I.=5 had a significantly higher risk of high seroprevalence. Given that the Vegetation Index is a steady indicator of the potential I. ricinus density in the biotope, we recommend that the risk of high B. divergens seroprevalence in cows be evaluated using this tool rather than drag samplings.

  4. Production and calving traits of Montbeliarde × Holstein and Viking Red × Holstein cows compared with pure Holstein cows during first lactation in 8 commercial dairy herds.

    PubMed

    Hazel, A R; Heins, B J; Hansen, L B

    2017-02-22

    Montbeliarde (MO) × Holstein (HO) and Viking Red (VR) × HO crossbred cows were compared with pure HO cows in 8 large, high-performance dairy herds. All cows were either 2-breed crossbred or pure HO cows that calved for the first time from December 2010 to April 2014. Best Prediction was used to calculate 305-d milk, fat, and protein production, as well as somatic cell score, and 513 MO × HO, 540 VR × HO, and 978 HO cows were analyzed for production in first lactation. Calving difficulty was scored from 1 (no assistance) to 5 (extreme difficulty). The analysis of calving traits included 493 MO × HO, 504 VR × HO, and 971 HO cows at first calving. Age at first calving was similar for breed groups, and the herds calved both crossbred (23.8 mo) and HO (23.9 mo) cows at young ages. The MO × HO crossbred cows had +3% higher production of 305-d fat plus protein production (actual basis, not mature equivalent) than the HO cows, and the VR × HO were similar to the HO cows for fat plus protein production. Breed groups did not differ for SCS during first lactation. The VR-sired 3-breed crossbred calves (from MO × HO dams) were similar to pure HO calves for calving difficulty; however, MO-sired male calves born to VR × HO dams had a mean score that was +0.5 points higher for calving difficulty than pure HO male calves. The 3-breed crossbred calves from both MO × HO (4%) and VR × HO (5%) first-lactation dams had a much lower stillbirth rate compared with pure HO calves (9%) from first-lactation dams.

  5. Efficacy of vaccination on Staphylococcus aureus and coagulase-negative staphylococci intramammary infection dynamics in 2 dairy herds.

    PubMed

    Schukken, Y H; Bronzo, V; Locatelli, C; Pollera, C; Rota, N; Casula, A; Testa, F; Scaccabarozzi, L; March, R; Zalduendo, D; Guix, R; Moroni, P

    2014-01-01

    The aim of this study was to evaluate vaccine efficacy of a commercial vaccine (Startvac, Hipra Spain) aimed at reducing intramammary infections (IMI) with Staphylococcus aureus and coagulase-negative staphylococci under field conditions. During the 21-mo duration of the study, 1,156 lactations from 809 cows were enrolled in 2 herds. During the first phase of the trial, all cows that were due to calve were vaccinated until approximately 50% of cows in the milking herd were vaccinated (at ~6mo). At that point, when 50% vaccination coverage was reached, cows that were due to calve were randomly assigned to be vaccinated or left as negative controls. Cure rate, rate of new infection, prevalence, and duration of infections were analyzed. Vaccination resulted in a moderate reduction in incidence of new staphylococcal IMI and a more pronounced reduction in duration of IMI associated with reduction of the basic reproduction ratio of Staph. aureus by approximately 45% and of coagulase-negative staphylococci by approximately 35%. The utilization of vaccine in combination with other infection-control procedures, such as excellent milking procedures, treatment, segregation, and culling of known infected cattle, will result in an important reduction in incidence and duration of intramammary staphylococcal infections.

  6. Coxiella burnetii total immunoglobulin G, phase I and phase II immunoglobulin G antibodies, and bacterial shedding in young dams in persistently infected dairy herds.

    PubMed

    Serrano-Pérez, Beatriz; Almería, Sonia; Tutusaus, Joan; Jado, Isabel; Anda, Pedro; Monleón, Eva; Badiola, Juan; Garcia-Ispierto, Irina; López-Gatius, Fernando

    2015-03-01

    The current study examines Coxiella burnetii infection patterns in young dairy dams around the calving period in persistently infected high-producing dairy herds. Infection patterns were determined in terms of total immunoglobulin G (IgG) and phase-specific IgG antibodies by enzyme-linked immunosorbent assay and bacterial shedding by real-time polymerase chain reaction (qPCR). On days 171-177 of gestation, at parturition, and on days 15-21 and 91-97 postpartum, 7 first-parity cows and 7 second-parity cows were sampled for serology and qPCR. Total phase-specific I (PhI) and II (PhII) IgG antibodies were detected in 2 animals at days 171-177 of gestation. Four additional animals underwent seroconversion on days 91-97 postpartum. Three of 6 seropositive dams according to total IgG, showed a PhI+/PhII+ profile, whereas dams that seroconverted exhibited a PhI-/PhII+ (2/6) or PhI+/PhII- (1/6) profile. An indirect fluorescent antibody test for PhI and PhII immunoglobulin M (IgM) was performed on plasma samples from the shedding dams, confirming seropositivity in a first-parity dam that seroconverted, and detecting a sudden spike of PhI-IgM antibodies in 1 further dam. No relationship was detected in young C. burnetii-infected animals between total IgG, PhI and/or PhII antibodies, and bacterial shedding throughout the study period. The highest bacterial load measured by qPCR was recorded in a second-parity dam. This animal presented abnormal peripheral blood counts, which would be an indication of severe peripheral blood alterations in some infected cattle. This study suggests that young shedder cows are mostly seronegative in early stages of infection.

  7. Genotype by environment interaction for milk production traits between organic and conventional dairy cattle production in The Netherlands.

    PubMed

    Nauta, W J; Veerkamp, R F; Brascamp, E W; Bovenhuis, H

    2006-07-01

    Estimates of genetic parameters for organic dairy farming have not been published previously, and neither is information available on the magnitude of genotype by environment interaction (GxE) between organic and conventional farming. However, organic farming is growing worldwide and basic information about genetic parameters is needed for future breeding strategies for organic dairy farming. The goal of this study was to estimate heritabilities of milk production traits under organic farming conditions and to estimate the magnitude of GxE between organic and conventional dairy farming. For this purpose, production records of first-parity Holstein heifers were used. Heritabilities of milk, fat and protein yield, and somatic cell score (SCS) were higher under organic farming conditions. For percentages of fat and protein, heritabilities of organic and conventional production were very similar. Genetic correlations between preorganic and organic, and organic and conventional milk production were 0.79 and 0.80, respectively. For fat yield, these correlations were 0.86 and 0.88, and for protein yield, these were 0.78 and 0.71, respectively. Our findings indicate that moderate GxE was present for yield traits. For percentage of fat and protein and SCS, genetic correlations between organic and conventional and preorganic production were close to unity, indicating that there was no GxE for these traits.

  8. Occurrence of Clinical and Sub-Clinical Mastitis in Dairy Herds in the West Littoral Region in Uruguay

    PubMed Central

    Gianneechini, R; Concha, C; Rivero, R; Delucci, I; López, J Moreno

    2002-01-01

    Twenty-nine dairy farms were selected to determine the incidence of clinical mastitis, prevalence of sub-clinical mastitis and bacterial aetiology in the West Littoral Region of Uruguay. In samples taken by the owner and frozen at -20°C during a week the incidence rate of clinical mastitis was determined as 1.2 cases per 100 cow-months at risk. Staphylococcus aureus was the most common isolated pathogen in 37.5% of 40 milk samples from clinical cases obtained in 1 month. No bacteria grew in the 32.5% of the total samples. A sub-sample including 1077 dairy cows from randomly selected farms was used to determine the prevalence of sub-clinical mastitis. These samples were taken on one visit to each farm. The prevalence was 52.4% on a cow basis and 26.7% on an udder quarter basis. In 55.1% of the quarters of the selected animals with more than 300 000 cells/ml there was no growth. The isolated pathogens from sub-clinical cases and their relative frequencies were: Staphylococcus aureus 62.8%, Streptococcus agalactiae 11.3%, Enterococcus sp. 8%, coagulase-negative staphylococci 7.4%, Streptococus uberis 6.4%, Streptococcus dysgalactiae 1.8%, Escherichia coli 1.5% and Staphylococcus hyicus coagulase-positive 0.6%. PMID:12831175

  9. Case study: Comparison of milk composition from adjacent organic and conventional farms

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A study of two adjacent dairy farms, one using conventional confined herd management and the other organic management with averages of 53 percent dry matter from pasture during the grazing season, revealed significant differences in the fatty acid composition of the milk. Compared with conventional...

  10. Antimicrobial susceptibility of Shiga toxin-producing Escherichia coli isolated from organic dairy farms, conventional dairy farms, and county fairs in Minnesota.

    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

    2007-01-01

    This study compared the antimicrobial susceptibility of Shiga toxin-producing Escherichia coli (STEC) isolates from organic dairy farms, conventional dairy farms, and Minnesota county fairs. A total of 83 STEC isolates (43 O157 and 40 non-O157 STEC) were tested for antimicrobial susceptibility as determined by the automated broth microdilution method. Resistance to tetracycline was identified in 19 (23%) isolates and to sulphadimethoxine in 40 (48%) isolates. Half of the STEC isolates were resistant to at least one antimicrobial agent. Resistance to at least one antimicrobial agent was observed in 18 (62%) isolates from conventional farms and in 11 (48%) isolates from organic farms. Resistance to at least one antimicrobial agent was more frequent in isolates from calves (77%) than from cows (39%). Multidrug resistant patterns were more common in non-O157 STEC than O157 STEC. This study provides data to document the degree of STEC antimicrobial resistance from dairy cattle sources in Minnesota. The use of antimicrobial agents on farms, and other environmental influences, may affect resistance patterns in isolates from cattle sources. Systematic surveillance of STEC from cattle could potentially detect emergence of antimicrobial resistance that may be spread to humans through the food chain.

  11. Communication in production animal medicine: modelling a complex interaction with the example of dairy herd health medicine

    PubMed Central

    2011-01-01

    Background The importance of communication skills in veterinary medicine is increasingly recognised. Appropriate communication skills towards the client are of utmost importance in both companion animal practice and production animal field and consultancy work. The need for building a relationship with the client, alongside developing a structure for the consultation is widely recognised and applies to both types of veterinary practice. Results Veterinary advisory practice in production animal medicine is, however, characterised by a more complex communication on different levels. While the person-orientated communication is a permanent process between veterinarian and client with a rather personal perspective and defines the roles of interaction, the problem-orientated communication deals with emerging difficulties; the objective is to solve an acute health problem. The solution - orientated communication is a form of communication in which both veterinarian and client address longstanding situations or problems with the objective to improve herd health and subsequently productivity performance. All three forms of communication overlap. Conclusions Based on this model, it appears useful for a veterinary practice to offer both a curative and an advisory service, but to keep these two separated when deemed appropriate. In veterinary education, the strategies and techniques necessary for solution orientated communication should be included in the teaching of communication skills. PMID:21777495

  12. Potential traceable markers of organic matter in organic and conventional dairy manure using ultraviolet–visible and solid-state 13C nuclear magnetic resonance spectroscopy

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Organic dairy (OD) production is drawing increasing attention because of public concerns about food safety, animal welfare and the potential environmental impacts of conventional dairy (CD) systems. However, very limited information is available on how organic farming practices affect the chemical ...

  13. Management factors affecting udder health and effects of a one year extension program in organic dairy herds.

    PubMed

    Ivemeyer, S; Walkenhorst, M; Heil, F; Notz, C; Maeschli, A; Butler, G; Klocke, P

    2009-11-01

    The first part of this study was a cross-sectional analysis of the impact of 29 management factors on udder health in organic dairy farms in Switzerland. All 77 farms joined the extension program 'pro-Q'. As a measure of udder health the theoretical bulk milk somatic cell count (TBMSCC) calculated by the monthly cow composite somatic cell count over a time period of 1 year was chosen. The basic udder health of the farms was determined by TBMSCC during the year prior to the start of the project (mean for all farms = 176 460 cells/ml). In the multivariable analysis, the five factors 'swiss brown breed', 'alpine summer pasturing', 'calf feeding with milk from mastitis diseased cows', 'hard bedding' and 'no post-milking' remained as significant risk factors on udder health. In the second part of the study, the development of management factors and the udder health situation affected by an extension program after 1 year was investigated. A partial improvement of the management factors on the farms but no overall improvement on udder health and no association between management changes and udder health changes were found. Improvement of udder health was more likely in farms with higher basic TBMSCC than in those farms with less udder health problems at the beginning of the project.

  14. The use of crossbreeding with beef bulls in dairy herds: effects on calving difficulty and gestation length.

    PubMed

    Fouz, R; Gandoy, F; Sanjuán, M L; Yus, E; Diéguez, F J

    2013-02-01

    This study was designed to analyse the evolution in the use of beef bull semen for dairy cattle insemination and, mainly, to assess calving difficulty, gestation length and proportion of stillbirths after breeding pure Holsteins or crossbreeding. Data were collected during 2004 to 2011 for 552 571 Holstein calvings (457 070 Holstein × Holstein, 43 384 Holstein × Limousine, 32 174 Holstein × Belgian Blue and 19 943 Holstein × Galician Blonde). The highest calving difficulty, compared with pure Holsteins was for crosses with Belgian Blue followed by Limousine and Galician Blonde. The Holstein × Limousine and Holstein × Galician Blonde crossbred calves had significantly longer gestation lengths than Holstein × Holstein and Holstein × Belgian Blue calves. Between the latter two, pure Holstein had the shortest gestation length. Calving difficulty and gestation length decreased as the age of the dam advanced. The most difficult calvings were observed in twin calvings, followed by the calvings of male calves and female calves. The gestations leading to the birth of male calves were longer than those leading to female calves and twin calves. Stillbirths were not related to the breed used for mating. Through examining these parameters, sire breed should be considered when selecting a beef breed for the insemination of milk-producing dams.

  15. 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.

  16. Short communication: Outbreak of methicillin-resistant Staphylococcus aureus (MRSA)-associated mastitis in a closed dairy herd.

    PubMed

    Guimarães, F F; Manzi, M P; Joaquim, S F; Richini-Pereira, V B; Langoni, H

    2017-01-01

    Cows are probably the main source of contamination of raw milk with Staphylococcus aureus. Mammary glands with subclinical mastitis can shed large numbers of Staph. aureus in milk. Because of the risk of this pathogen to human health as well as animal health, the aim of this paper was to describe an outbreak of mastitis caused by methicillin-resistant Staph. aureus (MRSA), oxacillin-susceptible mecA-positive Staph. aureus (OS-MRSA), and methicillin-susceptible Staph. aureus (MSSA) on a dairy farm. Milk samples were obtained from all quarters, showing an elevated somatic cell count by the California Mastitis Test. The isolates were identified by phenotypic and genotypic methods. Staphylococcus spp. were isolated from 53% (61/115) of the milk samples, with 60 isolates identified as Staph. aureus (98.4%) and 1 isolate identified as Staphylococcus epidermidis (1.6%). The presence of the mecA gene was verified in 48.3% of Staph. aureus isolates. Of the Staph. aureus isolates, 23.3% were MRSA and 25.0% were OS-MRSA. The total of mastitis cases infected with MRSA was 12.2%. The detection of this large percentage of mastitis cases caused by MRSA and OS-MRSA is of great concern for the animals' health, because β-lactams are still the most important antimicrobials used to treat mastitis. In addition, Staph. aureus isolates causing bovine mastitis represent a public health risk.

  17. Fatty acid profiles, meat quality, and sensory attributes of organic versus conventional dairy beef steers.

    PubMed

    Bjorklund, E A; Heins, B J; Dicostanzo, A; Chester-Jones, H

    2014-03-01

    Meat from Holstein and crossbred organic and conventional dairy steers were evaluated and compared for fatty acid profiles, meat quality, sensory attributes, and consumer acceptance. Bull calves (n=49) were randomly assigned to 1 of 3 replicated groups: conventional (CONV), organic (ORG, pasture + concentrate), or grass-fed organic (GRS) and were born at the University of Minnesota West Central Research and Outreach Center (Morris, MN) between March and May 2011. The CONV steers (n=16) were fed a diet that contained 80% concentrate and 20% forage, and ORG steers (n=16) were fed a diet of organic corn, organic corn silage, and organic protein supplement. Furthermore, ORG steers consumed at least 30% of diet dry matter of high-quality organic pasture during the grazing season. The GRS steers (n=17) consumed 100% forage from pasture during the grazing season and high-quality hay or hay silage during the nongrazing season. The ORG steers had fat that was greater in oleic acid (C18:1) than the GRS and CONV steers (47.1, 36.1, and 39.9%, respectively). The GRS steers (21.9%) were lower for monounsaturated fat than the ORG (42.1%) and CONV (40.4%) steers. Furthermore, the GRS steers tended to have greater n-3 fat and had lower n-6 fat than the ORG and CONV steers. Consequently, the GRS (1.4%) steers had a lower n-6-to-n-3 fat ratio than the ORG (12.9%) and CONV (10.0%) steers. The GRS (2.6 kg) steers had steaks that were not different for Warner-Bratzler shear force than ORG (2.3 kg) steaks; however, the GRS steaks tended to have greater shear force than the CONV (2.0 kg) steaks. The 3 steer group had steaks that were not different for color brightness (L*; 0 = black and 100 = white) and yellowness/blueness (b*; positive values = yellow and negative values = blue) values; however, the GRS (10.5) steaks had lower redness/greenness (a*; positive values = red and negative values = green) values than CONV (14.5) steaks. For sensory attributes (0- to 120-point scale), no

  18. Reproductive Performance, Udder Health, and Antibiotic Resistance in Mastitis Bacteria isolated from Norwegian Red cows in Conventional and Organic Farming

    PubMed Central

    2010-01-01

    Background The objectives of this study were to investigate whether there were differences between Norwegian Red cows in conventional and organic farming with respect to reproductive performance, udder health, and antibiotic resistance in udder pathogens. Methods Twenty-five conventional and 24 organic herds from south-east and middle Norway participated in the study. Herds were matched such that geographical location, herd size, and barn types were similar across the cohorts. All organic herds were certified as organic between 1997 and 2003. All herds were members of the Norwegian Dairy Herd Recording System. The herds were visited once during the study. The relationship between the outcomes and explanatory variables were assessed using mixed linear models. Results There were less > 2nd parity cows in conventional farming. The conventional cows had higher milk yields and received more concentrates than organic cows. Although after adjustment for milk yield and parity, somatic cell count was lower in organic cows than conventional cows. There was a higher proportion of quarters that were dried off at the herd visit in organic herds. No differences in the interval to first AI, interval to last AI or calving interval was revealed between organic and conventional cows. There was no difference between conventional and organic cows in quarter samples positive for mastitis bacteria from the herd visit. Milk yield and parity were associated with the likelihood of at least one quarter positive for mastitis bacteria. There was few S. aureus isolates resistance to penicillin in both management systems. Penicillin resistance against Coagulase negative staphylococci isolated from subclinically infected quarters was 48.5% in conventional herds and 46.5% in organic herds. Conclusion There were no large differences between reproductive performance and udder health between conventional and organic farming for Norwegian Red cows. PMID:20141638

  19. Eleven-year analysis of changes in the incidence and recurrence of cystic ovarian disease in a herd of dairy cattle in California.

    PubMed

    Scholl, D T; BonDurant, R H; Farver, T B

    1990-02-01

    Individual card records of all cows that began 1 or more lactations between the inclusive dates of Jan 1, 1976 and Dec 31, 1986 were obtained from a California dairy herd. Calving date, lactation number, physical examination date, conception date, and clinical findings pertinent to cystic ovarian disease (COD) were extracted from the records. Lactation-specific data were organized into cohorts by quarter and year in which lactation began, and the following estimates were calculated for each of the 44 cohorts: separate actuarial cumulative incidences for cows in their first lactation, cows in the second or later lactation, and all cows combined; separate proportions of the incident cases that were in their second or greater lactation and that had recurred from any previous lactation; proportions of the incident cases that had recurrence of COD 1 or more times, and recurrence 2 or more times during the lactation; and the mean number of days in lactation at diagnosis of the incident case. Time-series analysis and multiple-regression modeling procedures were used to characterize changes in the overall incidence rate over the study period and to describe the contribution of additional measures to the dynamics of the incidence rates. The quarterly actuarial cumulative incidences of COD increased concurrently with the increased incidence among cows in the second or later lactation. Neither the proportion of incident cases that were diseased during a previous lactation nor the proportion of cases that were in the second or later lactation contributed to the observed changes in the overall incidence rate.(ABSTRACT TRUNCATED AT 250 WORDS)

  20. A phylogenetically distinct Middle East respiratory syndrome coronavirus detected in a dromedary calf from a closed dairy herd in Dubai with rising seroprevalence with age.

    PubMed

    Wernery, Ulrich; El Rasoul, I Hassab; Wong, Emily Y M; Joseph, Marina; Chen, Yixin; Jose, Shanty; Tsang, Alan K L; Patteril, Nissy Annie Georgy; Chen, Honglin; Elizabeth, Shyna K; Yuen, Kwok-Yung; Joseph, Sunitha; Xia, Ningshao; Wernery, Renate; Lau, Susanna K P; Woo, Patrick C Y

    2015-12-02

    Middle East respiratory syndrome coronavirus (MERS-CoV) was detected by monoclonal antibody-based nucleocapsid protein-capture enzyme-linked immunosorbent assay (ELISA), RNA detection, and viral culture from the nasal sample of a 1-month-old dromedary calf in Dubai with sudden death. Whole genome phylogeny showed that this MERS-CoV strain did not cluster with the other MERS-CoV strains from Dubai that we reported recently. Instead, it formed a unique branch more closely related to other MERS-CoV strains from patients in Qatar and Hafr-Al-Batin in Saudi Arabia, as well as the MERS-CoV strains from patients in the recent Korean outbreak, in which the index patient acquired the infection during travel in the eastern part of the Arabian Peninsula. Non-synonymous mutations, resulting in 11 unique amino acid differences, were observed between the MERS-CoV genome from the present study and all the other available MERS-CoV genomes. Among these 11 unique amino acid differences, four were found in ORF1ab, three were found in the S1 domain of the spike protein, and one each was found in the proteins encoded by ORF4b, ORF5, envelope gene, and ORF8. MERS-CoV detection for all other 254 dromedaries in this closed dairy herd was negative by nucleocapsid protein-capture ELISA and RNA detection. MERS-CoV IgG sero-positivity gradually increased in dromedary calves with increasing age, with positivity rates of 75% at zero to three months, 79% at four months, 89% at five to six months, and 90% at seven to twelve months. The development of a rapid antigen detection kit for instantaneous diagnosis is warranted.Emerging Microbes & Infections (2015) 4, e74; doi:10.1038/emi.2015.74; published online 2 December 2015.

  1. Endometritis treatment with a PGF2alpha analog does not improve reproductive performance in a large dairy herd in Argentina.

    PubMed

    Mejía, Miguel Eduardo; Lacau-Mengido, Isabel María

    2005-03-15

    In Argentina, most dairy cows with endometritis are treated with prostaglandin (PGF(2alpha) or its analogs) and insemination is withheld until there are no signs of endometritis. The objective of the present study was to evaluate if this method of managing endometritis enhances reproductive performance. Three experiments were conducted over 4 years in a large farm in the west of Buenos Aires province. In Experiment 1, half of the cows diagnosed with endometritis (>1.5-fold difference in diameter of uterine horns, as determined by rectal palpation) received standard endometritis management (treatment with tiaprost, a PGF(2alpha) analog, rectal palpation every 20 days, and withholding of AI until endometritis apparently resolved) and the other half was untreated, with AI at the first estrus after the voluntary waiting period. Untreated cows were inseminated and conceived 20 days earlier than treated cows, and the pregnancy rate by Day 90 postpartum was higher in the untreated group. In Experiment 2, cows with endometritis were divided into four groups according to the severity of symptoms; within each group, cows were allocated to treatment or control, as in Experiment 1. Although first service conception rate decreased as endometritis severity increased, reproductive performance in treated versus control cows was similar to that of Experiment 1 (with no interaction due to degree of endometritis). Re-evaluation of the treated cow (to confirm uterine "normality") may have been responsible for the delay in conception in both experiments. The objective of Experiment 3 was to determine the effects of tiaprost treatment on clinically normal postpartum cows (no evidence of endometritis). Tiaprost treatment reduced the interval from calving to conception in multiparous cows, but it delayed conception and reduced the conception rate in primiparous cows. In conclusion, treatment with tiaprost impaired reproductive performance in primiparous cows (in the absence of

  2. Comparison of antibiotic resistance of udder pathogens in dairy cows kept on organic and on conventional farms.

    PubMed

    Roesch, M; Perreten, V; Doherr, M G; Schaeren, W; Schällibaum, M; Blum, J W

    2006-03-01

    There has been a rapid rise in the emergence of multi-drug-resistant pathogens in the past 10 to 15 yr and some bacteria are now resistant to most antimicrobial agents. Antibiotic use is very restricted on Swiss organic dairy farms, and a purely prophylactic use, such as for dry cow mastitis prevention, is forbidden. A low prevalence of antibiotic resistance in organic farms can be expected compared with conventional farms because the bacteria are infrequently or not exposed to antibiotics. The occurrence of antibiotic resistance was compared between mastitis pathogens (Staphylococcus aureus, nonaureus staphylococci, Streptococcus dysgalactiae, Streptococcus uberis) from farms with organic and conventional dairy production. Clear differences in the percentage of antibiotic resistance were mainly species-related, but did not differ significantly between isolates from cows kept on organic and conventional farms, except for Streptococcus uberis, which exhibited significantly more single resistances (compared with no resistance) when isolated from cows kept on organic farms (6/10 isolates) than on conventional farms (0/5 isolates). Different percentages were found (albeit not statistically significant) in resistance to ceftiofur, erythromycin, clindamycin, enrofloxacin, chloramphenicol, penicillin, oxacillin, gentamicin, tetracycline, and quinupristin-dalfopristin, but, importantly, none of the strains was resistant to amoxicillin-clavulanic acid or vancomycin. Multidrug resistance was rarely encountered. The frequency of antibiotic resistance in organic farms, in which the use of antibiotics must be very restricted, was not different from conventional farms, and was contrary to expectation. The antibiotic resistance status needs to be monitored in organic farms as well as conventional farms and production factors related to the absence of reduced antibiotic resistance in organic farms need to be evaluated.

  3. 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.

  4. Prevalence of antibodies against bluetongue virus serotype 8 in bulk-tank milk samples from dairy cattle herds located in risk areas for bluetongue virus transmission after a vaccination programme in Switzerland.

    PubMed

    Büchi, Martina; Abril, Carlos; Vögtlin, Andrea; Schwermer, Heinzpeter

    2014-01-01

    Switzerland had been affected by the bluetongue virus serotype 8 (BTV-8) epidemic in Europe in the years 2007 to 2009. After three years of mandatory vaccination and comprehensive surveillance, Switzerland showed to be free of BTV-8 in 2012. In the future Elisa testing of bulk-tank milk (BTM) samples as a very sensitive and cost-effective method should be used for the surveillance of all serotypes of BTV. To determine the prevalence of seropositive herds, BTM from 240 cattle herds was sampled in July 2012. The results showed an apparent seroprevalence of 98.7% in the investigated dairy herds. Most plausible, the high prevalence was caused by the vaccination campaigns rather than by infections with BTV-8. In the outbreak the cumulative number of BTV-8 cases in Switzerland had been 75.Thus it is very likely that the used inactivated vaccines induced long-term antibody titres. Due to the high seroprevalence, investigating for BT-antibodies cannot be used for early recognition of a new introduction of BTV at the moment. Nonetheless, testing of BTM samples is appropriate for an annual evaluation of the seroprevalence and especially as an instrument for early recognition for incursions as soon as the antibody prevalence declines.To determine this decline the BTM testing scheme should be conducted each year as described in this work.

  5. 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…

  6. Effects of Poultry litter and dairy manure applications on forage yield and quality in conventional and no-till established tall fescue (Scheonourous phoenix [Scop.] Holub) sward.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An endophyte-free tall fescue cultivar, ‘Bronson’ was seeded at a rate of 28kg per ha in the fall of 2010. Two establishment methods were utilized; conventional tillage and no-till establishment. Treatments included conventional fertilizer, poultry litter, and dairy manure along with an untreated co...

  7. 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

    organic dairy farms has increased globally and, given the pressure to decrease the use of antimicrobials and hormones, conventional farms may be able to learn from well-managed organic farms. The possibilities of using milk for disease diagnostics and monitoring are considerable, and dairy herd improvement associations will continue to expand the number of tests offered to diagnose diseases and pregnancy. Genetic and genomic selection for increased resistance to disease offers substantial potential but requires collection of additional phenotypic data. There is every expectation that changes in the dairy industry will be further accentuated and additional novel technologies and different management practices will be adopted in the future.

  8. Mastitis prevention and control practices and mastitis treatment strategies associated with the consumption of (critically important) antimicrobials on dairy herds in Flanders, Belgium.

    PubMed

    Stevens, M; Piepers, S; De Vliegher, S

    2016-04-01

    The main objectives of this study were to evaluate to what extent variations in herd-level antimicrobial consumption (AMC) can be explained by differences in management practices that are consistently effective in the prevention of (sub)clinical mastitis, on the one hand, and by differences in mastitis treatment strategies, on the other hand. Antimicrobial consumption data were obtained during 2012 and 2013 by "garbage can audits" and expressed as antimicrobial treatment incidences (ATI) for all compounds combined (total ATI) and for the critically important antimicrobials for human health separately. Data on mastitis prevention and control practices were obtained via face-to-face interviews performed during herd visits in March 2013. Some management practices and treatment strategies related to udder health were associated with the total AMC. However, the results demonstrated that implementing effective udder health management practices does not necessarily imply a low AMC and vice versa. Herds participating in a veterinary herd health management program and herds selectively drying off cows used fewer antimicrobials compared with herds not participating in such a program or applying blanket dry-cow therapy. Moreover, herds treating (some) (sub)clinical mastitis cases with intramammary homeopathic substances consumed fewer antimicrobials than herds not applying such homeopathic treatments. Besides these factors, no other direct association was found between effective udder health management practices on the one hand and AMC on the other hand. Also, the use of critically important antimicrobials was only associated with the way in which subclinical mastitis cases were treated. The latter indicates that the AMC of critically important antimicrobials is potentially driven by factors other than those included in this study such as those related to the "mindset" of the veterinarians and their farmers. Future research should therefore aim to unravel the reasoning of

  9. Fasciola hepatica - monitoring the milky way? The use of tank milk for liver fluke monitoring in dairy herds as base for treatment strategies.

    PubMed

    Duscher, Ruth; Duscher, Georg; Hofer, Johannes; Tichy, Alexander; Prosl, Heinrich; Joachim, Anja

    2011-06-10

    In this study 595 lactating cows originating from 31 carinthian farms were investigated in accordance of liver fluke infection using individual and tank milk as well as individual blood and faecal samples. Two commercial ELISAs were used to test the milk and blood serum, and the results were compared with coproscopy and a commercial copro-antigen ELISA. Receiver operating characteristics (ROC) and two-graph operating characteristics (TG ROC) of tank milk results were conducted based on the individual milk to determine the minimum reliable in-herd antibody prevalence for the predominant condition in the investigation area. In 17.8% of the examined individuals located in 64.5% of the farms eggs were detected by coproscopy. The copro-antigen ELISA delivered 13.4% positive individuals from 54.8% of the farms. The milk ELISAs showed 42.7% (Euroclone) and 44.2% (Pourquier) positive cows on 90.3% of the farms. The blood samples were positive in 43% (Euroclone) and 45.2% (Pourquier) of the individuals from 90.3% to 96.8% of the herds, respectively. Based on the milk and the blood an average in-herd prevalence of 30-45% can be assumed. The serum and milk samples delivered correlating results with kappa values between 0.94 and 0.97, whereas the coproscopy and copro-antigen ELISA did not correlate well with the ELISA results. The two different ELISA tests highly correlated on individual and on herd level. Both showed a reliable minimum in-herd prevalence of ∼20%, meaning that one fifth of the individuals in a herd have to be positive to obtain a positive bulk tank milk result. In the investigated area a higher in-herd prevalence is expected, therefore the tank milk is useful as a monitoring tool and can be used as a basis for intervention strategies.

  10. Influence of antibiotic selection on genetic composition of Escherichia coli populations from conventional and organic dairy farms.

    PubMed

    Walk, Seth T; Mladonicky, Janice M; Middleton, Jaclyn A; Heidt, Anthony J; Cunningham, Julie R; Bartlett, Paul; Sato, Kenji; Whittam, Thomas S

    2007-10-01

    The widespread agricultural use of antimicrobials has long been considered a crucial influence on the prevalence of resistant genes and bacterial strains. It has been suggested that antibiotic applications in agricultural settings are a driving force for the development of antimicrobial resistance, and epidemiologic evidence supports the view that there is a direct link between resistant human pathogens, retail produce, farm animals, and farm environments. Despite such concerns, little is understood about the population processes underlying the emergence and spread of antibiotic resistance and the reversibility of resistance when antibiotic selective pressure is removed. In this study, hierarchical log-linear modeling was used to assess the association between farm type (conventional versus organic), age of cattle (calf versus cow), bacterial phenotype (resistant versus susceptible), and the genetic composition of Escherichia coli populations (E. coli Reference Collection [ECOR] phylogroup A, B1, B2, or D) among 678 susceptible and resistant strains from a previously published study of 60 matched dairy farms (30 conventional and 30 organic) in Wisconsin. The analysis provides evidence for clonal resistance (ampicillin resistance) and genetic hitchhiking (tetracycline resistance [Tet(r)]), estimated the rate of compositional change from conventional farming to organic farming (mean, 8 years; range, 3 to 15 years), and discovered a significant association between low multidrug resistance, organic farms, and strains of the numerically dominant phylogroup B1. These data suggest that organic farming practices not only change the frequency of resistant strains but also impact the overall population genetic composition of the resident E. coli flora. In addition, the results support the hypothesis that the current prevalence of Tet(r) loci on dairy farms has little to do with the use of this antibiotic.

  11. Comparison between sire-maternal grandsire and animal models for genetic evaluation of longevity in a dairy cattle population with small herds.

    PubMed

    Jenko, J; Gorjanc, G; Kovač, M; Ducrocq, V

    2013-01-01

    Survival analysis techniques for sire-maternal grandsire (MGS) and animal models were used to test the genetic evaluation of longevity in a Slovenian Brown cattle population characterized by small herds. Three genetic models were compared: a sire-MGS model for bulls and an approximate animal model based on estimated breeding values (EBV) from the sire-MGS model for cows, an animal model, and an animal model based on the estimated variance components from the sire-MGS model. In addition, modeling the contemporary group effect was defined as either a herd or a herd-year (HY) effect. With various restrictions on the minimum HY group size (from 1 to 10 cows per HY), changes in estimates of variance components, and consequently also in EBV, were observed for the sire-MGS and animal models. Variance of contemporary group effects decreased when an HY effect was fitted instead of a herd effect. In the case of a sire-MGS model, estimates of additive genetic variance were mostly robust to changes in minimum HY group size or fitting herd or HY effect, whereas they increased in the animal model when HY instead of herd effects was fitted, possibly revealing some confounding between cow EBV and contemporary group effect. Estimated heritabilities from sire-MGS models were between 0.091 and 0.119 and were mainly influenced by the restriction on the HY group size. Estimated heritabilities from animal models were higher: between 0.125 and 0.160 when herd effect was fitted and between 0.171 and 0.210 when HY effect was fitted. Rank correlations between the animal model and the approximate animal model based on EBV from the sire-MGS model were high: 0.94 for cows and 0.93 for sires when a herd effect was fitted and 0.90 for cows and 0.93 for sires when an HY effect was fitted. Validation performed on the independent validation data set revealed that the correlation between sire EBV and daughter survival were slightly higher with the approximate animal model based on EBV from the sire

  12. Cattle and environmental sample-level factors associated with the presence of Salmonella in a multi-state study of conventional and organic dairy farms.

    PubMed

    Fossler, C P; Wells, S J; Kaneene, J B; Ruegg, P L; Warnick, L D; Eberly, L E; Godden, S M; Halbert, L W; Campbell, A M; Bolin, C A; Zwald, A M Geiger

    2005-01-01

    The objective of this study was to evaluate associations between cattle-level factors and environmental samples with the isolation of Salmonella from dairy farms in Minnesota, Wisconsin, Michigan, and New York. The study farms included 129 conventional and organic farms enrolled without regard to previous history of Salmonella infection. Herds were sampled at two-month intervals over a one-year period. Cattle groups more likely to be associated with Salmonella shedding (compared to preweaned calves) were cows designated as sick by farm personnel (OR=2.5, 95% CI: 1.7, 3.7), cows within 14 days of calving (OR=1.8, 95% CI: 1.1, 2.8), and cows due for culling within 14 days (OR=1.9, 95% CI: 1.0, 3.4). State of origin was also associated with the presence of Salmonella in samples from cattle and the farm environment; Midwestern states were more likely to have Salmonella-positive samples compared to New York. Cattle treated with antimicrobials within 14 days of sampling were more likely to be Salmonella-negative compared with nontreated cattle (OR=2.0, 95% CI: 1.1, 3.4). Farms with at least 100 cows were more likely to have Salmonella-positive cattle compared with smaller farms (OR=2.6, 95% CI: 1.4, 4.6). Season was associated with Salmonella shedding in cattle, and compared to the winter period, summer had the highest odds for shedding (OR=2.4, 95% CI: 1.5, 3.7), followed by fall (OR=1.9, 95% CI: 1.2, 3.1) and spring (OR=1.8, 95% CI: 1.2, 2.6). Environmental samples significantly more likely to be Salmonella-positive (compared to bulk tank milk) included, in descending order, samples from sick pens (OR=7.4, 95% CI: 3.4, 15.8), manure storage areas (OR=6.4, 95% CI: 3.5, 11.7), maternity pens (OR=4.2, 95% CI: 2.2, 8.1), haircoats of cows due to be culled (OR=3.9, 95% CI: 2.2, 7.7), milk filters (OR=3.3, 95% CI: 1.8, 6.0), cow waterers (OR=2.8, 95% CI: 1.4, 5.7), calf pens (OR=2.7, 95% CI: 1.3, 5.3), and bird droppings from cow housing (OR=2.4, 95% CI: 1.3, 4.4). Parity

  13. Cadmium and zinc in kidney, liver, muscle and mammary tissue from dairy cows in conventional and organic farming.

    PubMed

    Olsson, I M; Jonsson, S; Oskarsson, A

    2001-10-01

    Input of Cd to arable soils occurs mainly through atmospheric deposition and mineral fertilisers. Phosphate fertilisers are often contaminated with Cd. In organic farming the use of mineral fertilisers is restricted. The impact of conventional and organic farming on Cd and Zn levels in tissues from dairy cows was studied. Kidney, liver, muscle and mammary tissue samples were collected at slaughter from 67 cows, aged 30-95 months, in a project with conventional and organic production at the same farm. Samples were analysed by electrothermal atomic absorption spectrometry with a quality control programme. Significantly lower levels of Cd were found in cows from the organic system (n = 29) than from the conventional cows (n = 38) in kidney [330 +/- 100 (mean +/- s) micrograms kg-1 vs. 410 +/- 140], liver (33 +/- 15 vs. 44 +/- 19) and mammary tissue (0.38 +/- 0.14 vs. 0.59 +/- 0.37), while there were no differences in muscle (0.48 +/- 0.13 vs. 0.49 +/- 0.14). Organic cow kidneys had lower Zn levels than conventional cows (19 +/- 1.4 mg kg-1 vs. 20 +/- 2), whereas muscles had higher Zn levels than conventional cows (67 +/- 16 vs. 51 +/- 12). Cd and Zn in mammary tissue were positively related to age and milk production. There was a positive relationship between levels in kidney of Cd and metallothionein (MT) and a Cd/MT concentration ratio indicating protection from Cd-induced renal dysfunction. When older animals, that entered the project as milk-producing cows, were included the differences in kidney and liver Cd levels between the systems were no longer significant, while Cd in kidney became related to age- and production-related parameters. The change of significant relationships when older animals were included shows the importance of controlled conditions for environmental monitoring.

  14. 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

  15. Applications and cost benefits of sexed semen in pasture-based dairy production systems.

    PubMed

    Butler, S T; Hutchinson, I A; Cromie, A R; Shalloo, L

    2014-05-01

    Sexed semen technology is now commercially available in many countries around the world, and is primarily used in dairy cattle breeding. Sperm are sorted by flow cytometry on the basis of a 4% difference in DNA content between sperm containing X and Y chromosomes. Despite reliably producing a 90% gender bias, the fertility of the sexed semen product is compromised compared with conventional semen. The negative implications of the reduced fertility of sexed semen are amplified in seasonal systems of dairy production, as the importance of fertility is greater in these systems compared with year-round calving systems. A review of the literature indicates that conception rates (CR) to 1st service with frozen-thawed sexed semen are ~75% to 80% of those achieved with conventional frozen-thawed semen. Preliminary results from a large-scale field trial carried out in Ireland in 2013 suggest that significant improvements in the performance of sexed semen have been made, with CR of 87% of those achieved with conventional semen. The improved fertility of a sexed semen product that delivers a 90% gender bias has considerable implications for the future of breeding management in pasture-based dairy production systems. Sexed semen may facilitate faster, more profitable dairy herd expansion by increasing the number of dairy heifer replacements born. Biosecurity can be improved by maintaining a closed herd during the period of herd expansion. In a non-expansion scenario, sexed semen may be used to increase the value of beef output from the dairy herd. The replacement heifer requirements for a herd could be met by using sexed semen in the 1st 3 weeks of the breeding season, with the remaining animals bred to beef sires, increasing the sale value over that of a dairy bull calf. Alternatively, very short gestation sires could be used to shorten the calving interval. Market prices have a considerable effect on the economics of sexed semen use, and widespread use of sexed semen should

  16. Options in dairy data management.

    PubMed Central

    Etherington, W G; Kinsel, M L; Marsh, W E

    1995-01-01

    A great deal of progress has been made in the development of dairy herd management software in the last few years. At the same time, the speed, capacity, and portability of computer hardware have increased, while costs have decreased, thus encouraging use by veterinarians, dairy herd managers, and other industry support groups. A review of the literature indicates that an increasing number of producers, veterinarians, and other dairy industry service personnel are using computers and dairy herd management software in the delivery of their services (1-3,5,9-11,26-30,38,39). Wider adoption will occur if information generated through the use of these systems is directed towards the improvement of the profitability of dairy production. The quality of a decision is only as good as the information used to make it. In the past, the limited availability of reliable herd data has restricted our understanding of factors that influence herd performance. In essence, we must define what is normal before we can determine what is abnormal. More importantly, we must define what management practices are profitable and to what extent they increase revenue (31,32). Improved record keeping will benefit the dairy industry by allowing producers and dairy consultants to make profitable decisions based on more accurate and complete information. The ability to merge biological, management, and economic data may prove valuable in the evaluation of intervention at the herd and individual animal level.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7859210

  17. Cow hair allergen concentrations in dairy farms with automatic and conventional milking systems: From stable to bedroom.

    PubMed

    Böhlandt, A; Schierl, R; Heizinger, J; Dietrich-Gümperlein, G; Zahradnik, E; Bruckmaier, L; Sültz, J; Raulf, M; Nowak, D

    2016-01-01

    Bovine hair and dander are considered to be a notable risk factor for sensitization and allergic symptoms in occupationally exposed cattle farmers due to various IgE binding proteins. Farmers are suspected not only to be exposed during their work inside the stables but also inside their homes as allergens could be transferred via hair and clothes resulting in continued bovine allergen exposure in private areas. In recent years a new sensitive sandwich ELISA (enzyme linked immunosorbent assay) test has been developed to measure the cow hair allergen (CHA) concentration in dust. The aim of the present study was to determine the CHA concentration in airborne and settled dust samples in stables and private rooms of dairy cattle farms with automatic milking systems (AM) and conventional milking systems (CM), also with respect to questionnaire data on farming characteristics. For this purpose different sampling techniques were applied, and results and practicability of the techniques were compared. Dust sampling was performed in the stable, computer room (only AM), changing room, living room and bedroom (mattress) of 12 dairy farms with automatic milking systems (AM group) and eight dairy farms with conventional milking systems (CM group). Altogether, 90 samples were taken by ALK filter dust collectors from all locations, while 32 samples were collected by an ion charging device (ICD) and 24 samples by an electronic dust fall collector (EDC) in computer rooms (AM) and/or changing and living rooms (not stables). The dust samples were extracted and analyzed for CHA content with a sandwich ELISA. At all investigated locations, CHA concentrations were above the limit of detection (LOD) of 0.1 ng/ml dust extract. The median CHA concentrations in dust collected by ALK filters ranged from 63 to 7154 μg/g dust in AM farms and from 121 to 5627 μg/g dust in CM farms with a steep concentration gradient from stables to bedrooms. ICD sampling revealed median CHA contents of 112

  18. Production and economic performance of F1-crossbred dairy cattle fed non-conventional protein supplements in Zimbabwe.

    PubMed

    Gusha, Jacob; Manyuchi, Clive Rolex; Imbayarwo-Chikosi, Venancio Edward; Hamandishe, Vimbayi Rangaridzo; Katsande, Simbarashe; Zvinorova, Plaxedis Ivy

    2014-01-01

    The effects of supplementing crossbred cows with non-conventional protein sources on dry matter intake, milk yield parameters and economic returns were investigated. Twenty-five lactating F1 Holstein-Mashona crossbreds averaging 115 ± 24 days in milk were used. Five treatments, total mixed ration (TMR), urea-treated maize stover, untreated maize stover, Macroptilium atropurpureum (Siratro) hay and veld hay, were randomly assigned to cows and replicated five times in a completely randomised design. Nutrient composition, intake, milk yield and economic returns were determined. M. atropurpureum hay, urea-treated maize stover and TMR had equal crude protein content. Daily dry matter intake and yield differed significantly among the treatment diets (P < 0.05). Cows on TMR, urea-treated maize stover and M. atropurpureum consumed more (P < 0.05) than cows on untreated maize stover and veld hay. Supplementing with TMR, urea-treated maize stover and M. atropurpureum hay increased (P < 0.05) milk yields. Mean daily milk yield was highest for cows supplemented with urea-treated maize stover. Percent fat, protein and total solids in milk from cows fed urea-treated stover compared favourably to that of milk for cows supplemented with TMR. Income over supplement cost was highest for cows supplemented with M. atropurpureum hay and urea-treated maize stover. Urea-treated maize stover and M. atropurpureum can therefore be used as a replacer protein supplements for dairy cattle in Zimbabwe.

  19. The effect of feed demand on greenhouse gas emissions and farm profitability for organic and conventional dairy farms.

    PubMed

    Kiefer, Lukas; Menzel, Friederike; Bahrs, Enno

    2014-12-01

    The reduction of product-related greenhouse gas (GHG) emissions in milk production appears to be necessary. The reduction of emissions on an individual farm might be highly accepted by farm owners if it were accompanied by an increase in profitability. Using life cycle assessments to determine the product carbon footprints (PCF) and farm-level evaluations to record profitability, we explored opportunities for optimization based on analysis of 81 organic and conventional pasture-based dairy farms in southern Germany. The objective of the present study was to detect common determining factors for low PCF and high management incomes (MI) to achieve GHG reductions at the lowest possible operational cost. In our sample, organic farms, which performed economically better than conventional farms, produced PCF that were significantly higher than those produced by conventional farms [1.61 ± 0.29 vs. 1.45 ± 0.28 kg of CO₂ equivalents (CO₂eq) per kg of milk; means ± SD)]. A multiple linear regression analysis of the sample demonstrated that low feed demand per kilogram of milk, high grassland yield, and low forage area requirements per cow are the main factors that decrease PCF. These factors are also useful for improving a farm's profitability in principle. For organic farms, a reduction of feed demand of 100 g/kg of milk resulted in a PCF reduction of 105 g of CO₂eq/kg of milk and an increase in MI of approximately 2.1 euro cents (c)/kg of milk. For conventional farms, a decrease of feed demand of 100 g/kg of milk corresponded to a reduction in PCF of 117 g of CO₂eq/kg of milk and an increase in MI of approximately 3.1 c/kg of milk. Accordingly, farmers could achieve higher profits while reducing GHG emissions. Improved education and training of farmers and consultants regarding GHG mitigation and farm profitability appear to be the best methods of improving efficiency under traditional and organic farming practices.

  20. Modeling the effect of seasonal variation in ambient temperature on the transmission dynamics of a pathogen with a free-living stage: example of Escherichia coli O157:H7 in a dairy herd.

    PubMed

    Gautam, Raju; Bani-Yaghoub, Majid; Neill, William H; Döpfer, Dörte; Kaspar, Charles; Ivanek, Renata

    2011-10-01

    To explore the potential role of ambient temperature on infection transmission dynamics for pathogens, we used Escherichia coli O157:H7 in a dairy herd and the surrounding farm environment as a model system. For this system, we developed a mathematical model in which a Susceptible-Infectious-Susceptible (SIS) model of infection spread through the host population is coupled with a metapopulation model of E. coli O157:H7 free-living stage in the environment allowing bacterial growth to be influenced by ambient temperature. Model results indicate that seasonal variation in ambient temperature could have a considerable impact on pathogen populations in the environment, specifically on barn surfaces and in water troughs, and consequently on the prevalence of infection in the host population. Based on model assumptions, contaminated drinking water was the most important pathway of E. coli O157:H7 transmission to cattle. Sensitivity analysis indicated that water-borne transmission is amplified during the warmer months if the amount of standing drinking water available to the cattle herd is high. This is because warmer ambient temperature favors faster pathogen replication which when combined with slower water replacement-rate due to high amount of available standing water leads to a greater pathogen load in drinking water. These results offer a possible explanation of the seasonal variation in E. coli O157:H7 prevalence in cattle and suggest that improved drinking-water management could be used for control of this infection in cattle. Our study demonstrates how consideration of ambient temperature in transmission cycles of pathogens able to survive and grow in the environment outside the host could offer novel perspectives on the spread and control of infections caused by such pathogens.

  1. An analysis of the intake of iodine-131 by a dairy herd post-Fukushima and the subsequent excretion in milk.

    PubMed

    Treinen, Richard M

    2015-11-01

    This study focuses on iodine-131 detected in milk samples from the Dairy Science Unit at Cal Poly, San Luis Obispo, California following events at the Fukushima Dai-ichi Nuclear Power Plant in March of 2011. The milk samples, collected between March 21 and April 11, 2011, were part of the Diablo Canyon Nuclear Power Plant Radiological Environmental Monitoring Program. A correlation is made between the integrated activity of iodine-131 found in milk and the integrated activities of iodine-131 of rainwater, vegetation and air samples that were collected from March 19 to April 18, 2011. A comparison is then made to previous studies conducted on dairy cattle that were administered controlled amounts of iodine-131 through ingestion. The comparison shows good agreement to the model which states that generally 1 percent of the activity of iodine-131 ingested by dairy cattle will be detected in harvested milk. Considering the environmental factors and the uncertainties involved, these data and calculated results derived from a real world situation provide an excellent application and confirmation of studies done under controlled settings.

  2. Quality and developmental rate of embryos produced with sex-sorted and conventional semen from superovulated dairy cattle.

    PubMed

    Mikkola, M; Taponen, J

    2017-01-01

    This study investigated the effect of sex-sorted semen compared with conventional semen on the outcome of embryo recovery, placing special emphasis on the quality, and developmental stage of embryos. Data were analyzed for 443 embryo collections with sex-sorted semen (SEX group) and 1528 with conventional semen (CONV group) in superovulated dairy heifers and cows. The insemination protocol for conventional semen included two inseminations, comprising a total dose of 30 million sperm passing into the uterine body. For sex-sorted semen, two (30%) to three (70%) deep uterine inseminations were performed, the total dose ranging from eight to 12 million sperm. The data were analyzed separately for heifers and cows. The total number of recovered structures was similar among the groups. The number of viable embryos decreased in the SEX groups compared with the CONV (with 1.4 and 3.2 fewer embryos in heifers and cows, correspondingly, P < 0.001), and correspondingly the proportions of unfertilized ova and degenerated embryos increased in the SEX groups (P < 0.001). The proportion of unsuccessful collections, yielding no transferable embryos, increased in the SEX groups for both heifers (from 7.2% to 11.2%, P = 0.025) and cows (from 9.0% to 20.7%, P < 0.001). Regarding the quality of viable embryos, the quality grades were superior in the CONV group compared with the SEX group for heifers (P < 0.001) and cows (P < 0.001). The proportion of grade 1 embryos decreased by 6.5 percentage points in heifers and 11.9 percentage points in cows when sex-sorted semen was used. Correspondingly, the proportions of grade 2 and 3 embryos increased in heifers and cows when sexed semen was used. The mean developmental stages of embryo collections were numerically slightly lower in the SEX group. In heifers, the delay in developmental stage was statistically significant (P = 0.001), but in cows, there was only a tendency toward that (P = 0.067). In conclusion, sex-sorted sperm

  3. Bovine respiratory syncytial virus: infection dynamics within and between herds

    PubMed Central

    Klem, T. B.; Gulliksen, S. M.; Lie, K.-I.; Løken, T.; Østerås, O.; Stokstad, M.

    2013-01-01

    The infection dynamics of bovine respiratory syncytial virus (BRSV) were studied in randomly selected Norwegian dairy herds. A total of 134 herds were tested twice, six months apart. The herds were classified as positive for BRSV if at least one animal between 150 and 365 days old tested positive for antibodies against BRSV, thereby representing herds that had most likely had the virus present during the previous year. The prevalence of positive herds at the first and second sampling was 34 per cent and at 41 per cent, respectively, but varied greatly between regions. Negative herds were found in close proximity to positive herds. Some of these herds remained negative despite several new infections nearby. Of the herds initially being negative, 42 per cent changed status to positive during the six months. This occurred at the same rate during summer as winter, but a higher rate of animals in the herds was positive if it took place during winter. Of the herds initially being positive, 33 per cent changed to negative. This indicates that an effective strategy to lower the prevalence and the impact of BRSV could be to employ close surveillance and place a high biosecurity focus on the negative herds. PMID:24158321

  4. 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

  5. Growth rate, health and welfare in a dairy herd with natural suckling until 6-8 weeks of age: a case report.

    PubMed

    Grøndahl, Ann Margaret; Skancke, Ellen Margrete; Mejdell, Cecilie Marie; Jansen, Johan Høgset

    2007-06-23

    Over a period of two years, growth rate and health were measured for dairy calves allowed to suckle their mothers up to 6-8 weeks of age. Thirty-one calves were weighted weekly, and the mean daily growth rate was 1.2 +/- 0.03 kg from birth up to 13 weeks of age. Illness in calves and young stock was not observed. In the cows, the mean incidences of ketosis, displaced abomasum, puerperal paresis, mastitis, teat injury and retained placenta were 0, 0, 8, 22, 1 and 1%, respectively, during a 6-year period. The mean daily gain of 56 growing bulls was 1.4 kg when slaughtered at 15 months of age, which is higher than the mean daily gain of 0.95 kg in the population. Probiotics, hormones and vaccines were not used, and antibiotics were only used for treating illness. The present study indicates many advantages and few problems when dairy calves are penned together with the cows and allowed natural feeding up to 6-8 weeks of age. This production system was easy to manage, preferred by the farmer, and may satisfy the public concern regarding the practice of immediate separation of cow and calf in commercial milk production.

  6. Genetic mechanisms contributing to reduced tetracycline susceptibility of Campylobacter isolated from organic and conventional dairy farms in the midwestern and northeastern United States.

    PubMed

    Halbert, Lisa W; Kaneene, John B; Linz, John; Mansfield, Linda S; Wilson, Dave; Ruegg, Pamela L; Warnick, Lorin D; Wells, Scott J; Fossler, Charles P; Campbell, Amy M; Geiger-Zwald, Angela M

    2006-03-01

    Campylobacter is one of the most common causes of gastroenteritis and can be acquired through contact with farm animals or the consumption of raw milk. Because of concerns over the role of food-producing animals in the dissemination of antimicrobial resistance to humans, we evaluated the prevalence of antimicrobial resistance in Campylobacter isolates from dairy farms and the genetic mechanism conferring the observed resistance. Evaluation of antimicrobial resistance was completed on 912 isolates from conventional and 304 isolates from organic dairy farms to eight drugs (azithromycin, chloramphenicol, ciprofloxacin, clindamycin, erythromycin, gentamicin, nalidixic acid, and tetracycline) with microbroth dilution. Resistance to seven of eight drugs was very low and did not differ by farm type. However, tetracycline resistance was common in Campylobacter isolated from both organic and conventional dairy farms, with 48 and 58% of isolates affected, respectively. By multiplex PCR, we determined that tetracycline resistance was highly associated with the carriage of tetO in Campylobacter isolates (X2 = 124, P < 0.01, kappa = 0.86).

  7. [Veterinary medicine and organic animal husbandry. III. Animal health in organic dairy farms].

    PubMed

    van Klink, E G; de Ruyter, W G; Sijpkens, C D; van Ham, P W

    1995-03-01

    Animal health is dealt with differently on biological farms then on conventional farms. On biological farms, stockmen see their animals not only as individual animals, but also as part of a herd in a balanced ecosystem. Disease prevention is therefore given much thought. The use of medicines is selective and subjected to strict regulations. This paper presents a summary of disease incidence in dairy cattle on biological farms and highlights specific problems and problem prevention in biological animal husbandry.

  8. Comparison of Greenhouse Gas Emissions between Two Dairy Farm Systems (Conventional vs. Organic Management) in New Hampshire Using the Manure DNDC Biogeochemical Model

    NASA Astrophysics Data System (ADS)

    Dorich, C.; Contosta, A.; Li, C.; Brito, A.; Varner, R. K.

    2013-12-01

    Agriculture contributes 20 to 25 % of the total anthropogenic greenhouse gas (GHG) emissions globally. These agricultural emissions are primarily in the form of methane (CH4) and nitrous oxide (N2O) with these GHG accounting for roughly 40 and 80 % of the total anthropogenic emissions of CH4 and N2O, respectively. Due to varied management and the complexities of agricultural ecosystems, it is difficult to estimate these CH4 and N2O emissions. The IPCC emission factors can be used to yield rough estimates of CH4 and N2O emissions but they are often based on limited data. Accurate modeling validated by measurements is needed in order to identify potential mitigation areas, reduce GHG emissions from agriculture, and improve sustainability of farming practices. The biogeochemical model Manure DNDC was validated using measurements from two dairy farms in New Hampshire, USA in order to quantify GHG emissions under different management systems. One organic and one conventional dairy farm operated by the University of New Hampshire's Agriculture Experiment Station were utilized as the study sites for validation of Manure DNDC. Compilation of management records started in 2011 to provide model inputs. Model results were then compared to field collected samples of soil carbon and nitrogen, above-ground biomass, and GHG fluxes. Fluxes were measured in crop, animal, housing, and waste management sites on the farms in order to examine the entire farm ecosystem and test the validity of the model. Fluxes were measured by static flux chambers, with enteric fermentation measurements being conducted by the SF6 tracer test as well as a new method called Greenfeeder. Our preliminary GHG flux analysis suggests higher emissions than predicted by IPCC emission factors and equations. Results suggest that emissions from manure management is a key concern at the conventional dairy farm while bedded housing at the organic dairy produced large quantities of GHG.

  9. 75 FR 81090 - Brucellosis Class Free States and Certified Brucellosis-Free Herds; Revisions to Testing and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-27

    ... testing protocol for maintaining the certified brucellosis- free status of dairy herds, which will give... removing the requirement for twice-yearly brucellosis ring testing of dairy cattle herds producing milk for... prevalence level of less than 1 infected animal per 1 million animals (0.0001 percent) in the National...

  10. Herd-level risk factors for antimicrobial demanding gastrointestinal diseases in Danish herds with finisher pigs: A register-based study.

    PubMed

    Hybschmann, G K; Ersbøll, A K; Vigre, H; Baadsgaard, N P; Houe, H

    2011-02-01

    Endemic gastrointestinal (GI) diseases have a substantial negative impact on pig production, because, when present, they reduce animal welfare, productivity and generate high antimicrobial (AM) demand. In Danish legislation, AM can be prescribed only for therapeutic purposes. The objective of the study was to estimate the association between herd-level risk factors and the amount of AM use (AMU) in connection with GI diseases in finisher herds. We conducted a register-based cross-sectional study with repeated measurements from 2004 to 2007. Data were extracted from databases in the Danish Register of Veterinary Medicine, the Central Husbandry Register and the Danish Agriculture and Food Council. In total, 3192 pig herds with 26,973 records (quarters with prescriptions) were included. The outcome was presented as average AM use (measured as Animal Daily Dosage) for GI diseases per finishing pig per quarter per herd. Three potential herd-level risk factors were evaluated: herd size (number of finishers delivered for slaughter); herd health status (herds in the Specific Pathogen Free (SPF) System, conventional herds); and herd type (herds including only finishers, integrated herds). Data were analyzed using general linear mixed models with repeated measurements. Smaller herds had a larger AMU per finisher than larger herds. Integrated herds had lower AMU as compared with herds with only finishers. Herds within the SPF System had a larger decrease in AMU with increasing herd size compared to conventional herds. Significant regional differences in AMU were seen. Additionally, the results showed that other herd factors and veterinarians were more influential than the investigated herd risk factors. This illustrates the difficulties of characterising AM-demanding GI diseases in herds by the use of register data only.

  11. Field trial on glucose-induced insulin and metabolite responses in Estonian Holstein and Estonian Red dairy cows in two herds

    PubMed Central

    2010-01-01

    Background Insulin secretion and tissue sensitivity to insulin is considered to be one of the factors controlling lipid metabolism post partum. The objective of this study was to compare glucose-induced blood insulin and metabolite responses in Estonian Holstein (EH, n = 14) and Estonian Red (ER, n = 14) cows. Methods The study was carried out using the glucose tolerance test (GTT) performed at 31 ± 1.9 days post partum during negative energy balance. Blood samples were obtained at -15, -5, 5, 10, 20, 30, 40, 50 and 60 min relative to infusion of 0.15 g/kg BW glucose and analysed for glucose, insulin, triglycerides (TG), non-esterified fatty acids (NEFA), cholesterol and β-hydroxybutyrate (BHB). Applying the MIXED Procedure with the SAS System the basal concentration of cholesterol, and basal concentration and concentrations at post-infusion time points for other metabolites, area under the curve (AUC) for glucose and insulin, clearance rate (CR) for glucose, and maximum increase from basal concentration for glucose and insulin were compared between breeds. Results There was a breed effect on blood NEFA (P < 0.05) and a time effect on all metabolites concentration (P < 0.01). The following differences were observed in EH compared to ER: lower blood insulin concentration 5 min after glucose infusion (P < 0.05), higher glucose concentration 20 (P < 0.01) and 30 min (P < 0.05) after infusion, and higher NEFA concentration before (P < 0.01) and 5 min after infusion (P < 0.05). Blood TG concentration in ER remained stable, while in EH there was a decrease from the basal level to the 40th min nadir (P < 0.01), followed by an increase to the 60th min postinfusion (P < 0.01). Conclusion Our results imply that glucose-induced changes in insulin concentration and metabolite responses to insulin differ between EH and ER dairy cows. PMID:20089161

  12. Changes in hoof health and animal hygiene in a dairy herd after covering concrete slatted floor with slatted rubber mats: a case study.

    PubMed

    Ahrens, F; Platz, S; Link, C; Mahling, M; Meyer, H H D; Erhard, M H

    2011-05-01

    The objective was to investigate the effect of changing the flooring in the alleys of a barn from slatted concrete to slatted rubber mats on hoof disorders and animal hygiene in 44 loose-housed Brown Swiss dairy cows. Cows were examined for disorders of the hind hooves (hemorrhages, white line fissures, ulcers, heel horn erosion, and digital dermatitis) and for skin lesions. The dirtiness of the animals and of the floor was recorded. Climatic (temperature, humidity) and ammonia gas conditions were measured. Evaluations were carried out when the cows were housed on a concrete slatted floor and after 4 and 10 mo on soft flooring (slatted rubber mats, 29-mm thick). The anatomical portion of claw (medial, lateral), number of lactations (parity), and days in milk were included as covariates in the statistical model. Changing the flooring from slatted concrete to slatted rubber mats increased the score for white line fissures [1.0 ± 0.3 (concrete) vs. 2.5 ± 0.4 (10 mo rubber mats)] and influenced air humidity (i.e., the difference in the absolute humidity between the inside and outside of the barn increased from 1.5 ± 0.1 to 1.7 ± 0.2g/m(3)), whereas the other hoof disorders, skin lesions (score of 8.7 ± 0.3), the dirtiness of the animals (score of 5.9 ± 0.3), and the floor (score of 2.1 ± 0.1), and ammonia gas concentration (2.6 ± 0.3mg/kg) were not affected (overall scores or measures; mean ± SE). Lateral claws were more affected (except for heel horn erosion) than medial claws (estimated effects between 1.3 ± 0.2 and 3.0 ± 0.6). Parity influenced hoof disorders (except for hemorrhages) and skin lesions (estimated effects between -0.6 ± 0.3 and 0.5 ± 0.2). Days in milk influenced hoof disorders, but had no effect on skin lesions and on the dirtiness of the animal. Irrespective of floor type, the slots (2.6 ± 0.1) were dirtier than the slats (1.6 ± 0.1). In conclusion, covering slatted concrete flooring with slatted rubber mats partially impaired hoof

  13. Prevalence and distribution of paratuberculosis (Johne's disease) in cattle herds in Ireland

    PubMed Central

    2009-01-01

    A simple random survey was conducted in Ireland during 2005 to estimate the ELISA-prevalence of paratuberculosis, commonly called Johne's disease (JD), in the cattle population. Serum samples were collected from all 20,322 females/breeding bulls over 12 months-of-age in 639 herds. All samples were tested using a commercially available absorbed ELISA. The overall prevalence of infected herds, based on the presence of at least one ELISA-positive animal, was 21.4% (95% CI 18.4%-24.9%). Herd prevalence levels amongst dairy herds (mean 31.5%; 95% CI: 24.6%, 39.3%) was higher than among beef herds (mean 17.9%; 95% CI: 14.6%-21.8%). However, the animal level prevalence was similar. The true prevalence among all animals tested, was calculated to be 2.86% (95%CI: 2.76, 2.97) and for animals >= 2 yrs, it was 3.30% (95%CI: 3.17, 3.43). For animals in beef herds, true prevalence was 3.09% (95%CI: 2.93, 3.24), and for those in dairy herds, 2.74% (95%CI: 2.59, 2.90). The majority of herds had only one ELISA-positive infected animal. Only 6.4% (95% CI 4.7%-8.7%) of all herds had more than one ELISA-positive infected animal; 13.3% (CI 8.7%-19.7%) of dairy herds ranging from two to eight ELISA-positive infected animals; and, 3.9% beef herds (CI 2.4%-6.2%) ranging from two to five ELISA-positive infected animals. The true prevalence of herds infected and shedding Mycobacterium avium subspecies paratuberculosis is estimated to be 9.5% for all herd types; 20.6% for dairy herds; and 7.6% for beef herds. If ELISA positive animals <2-years-of-age are excluded, the true herd prevalene reduces to: 9.3% for all herd types; 19.6% for dairy herds; and 6.3% for beef herds based on a test specificity (Sp) of 99.8% and test sensitivity (Se) (i.e., ability to detect culture-positive, infected animals shedding at any level) of 27.8-28.9%. PMID:21851740

  14. Farm Management in Organic and Conventional Dairy Production Systems Based on Pasture in Southern Brazil and Its Consequences on Production and Milk Quality.

    PubMed

    Kuhnen, Shirley; Stibuski, Rudinei Butka; Honorato, Luciana Aparecida; Filho, Luiz Carlos Pinheiro Machado

    2015-07-09

    Pasture-based dairy production is used widely on family dairy farms in Southern Brazil. This study investigates conventional high input (C-HI), conventional low input (C-LI), and organic low input (O-LI) pasture-based systems and their effects on quantity and quality of the milk produced. We conducted technical site visits and interviews monthly over one year on 24 family farms (n = 8 per type). C-HI farms had the greatest total area (28.9 ha), greatest percentage of area with annual pasture (38.7%), largest number of lactating animals (26.2) and greatest milk yield per cow (22.8 kg·day(-1)). O-LI farms had the largest perennial pasture area (52.3%), with the greatest botanical richness during all seasons. Area of perennial pasture was positively correlated with number of species consumed by the animals (R² = 0.74). Milk from O-LI farms had higher levels of fat and total solids only during the winter. Hygienic and microbiological quality of the milk was poor for all farms and need to be improved. C-HI farms had high milk yield related to high input, C-LI had intermediate characteristics and O-LI utilized a year round perennial pasture as a strategy to diminish the use of supplements in animal diets, which is an important aspect in ensuring production sustainability.

  15. Herd-level prevalence and associated risk factors for Toxoplasma gondii, Neospora caninum, Chlamydia abortus and bovine viral diarrhoea virus in commercial dairy and beef cattle in eastern, northern and northeastern China.

    PubMed

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

    2015-11-01

    Although the seroprevalence of Toxoplasma gondii, Neospora caninum, Chlamydia abortus and bovine viral diarrhea virus infection in cattle have been reported in some areas in China, most of them were conducted with small number of cattle samples and very limited districts and neglected the assessment of herd management factors associated with herd-level prevalence of these pathogen infections. Thus, from September 2013 to December 2014, a large-scale seroprevalence study was conducted to determine the animal-level and herd-level seroprevalence and identify herd-level risk factors associated with these pathogen infections in 4487 cattle from 134 herds in five provinces (Heilongjiang, Jilin, Liaoning, Shandong, Hebei) and Inner Mongolia Autonomous Region of China. At animal level, the true prevalence of antibodies against T. gondii, N. caninum, C. abortus and bovine viral diarrhoea virus (BVDV) was 10.48, 17.14, 11.92 and 50.10%, respectively. At herd level, the true prevalence of antibodies against T. gondii, N. caninum, C. abortus and BVDV was 27.16, 29.10, 37.31 and 40.30%, respectively. Multivariate analysis of these characteristics showed that source of water and presence of felids were significantly associated with T. gondii infection in the studied cattle herds. Source of water was significantly associated with N. caninum infection in the studied cattle herds. While herd size and management system were significantly associated with BVDV infection in the studied cattle herds, this is the first report of herd-level prevalence and associated risk factors of T. gondii, N. caninum, C. abortus and BVDV infection in cattle in China.

  16. Bayesian estimation of true between-herd and within-herd prevalence of Salmonella in Danish veal calves.

    PubMed

    Nielsen, T D; Nielsen, L R; Toft, N

    2011-07-01

    Specialised veal producers that purchase and raise calves from several dairy herds are potentially at high risk of delivering Salmonella-infected animals to slaughter. However, the true prevalence of Salmonella infected veal producing herds and the prevalence of infected calves delivered to slaughter from infected herds are unknown in Denmark. Due to uncertainties about test sensitivity and specificity, these prevalences are not straightforward to assess. The objective of this study was to estimate the within-herd- and between-herd prevalence of Salmonella in veal calves delivered for slaughter to abattoirs in Denmark. Furthermore, it was investigated to which extent the estimates differed between a setup using both serological tests and faecal culture, compared to just serological tests, and whether the applied sampling scheme in the national surveillance programme in Denmark was sufficient to establish high posterior estimates of freedom from infection in individual herds. We used Bayesian analysis to avoid bias as a result of fixed test validity estimates. Serological test results from 753 animals and faecal culture from 1233 animals from 68 randomly selected Danish veal producing herds that delivered more than 100 calves to slaughter per year were used to estimate the prevalences and estimates of freedom from Salmonella. Serological test results of 7726 animals from 185 herds were used to compare the difference in prevalence estimates between serology alone vs. faecal culture combined with serology. We estimated that 34-57% of specialised veal producing herds were infected with Salmonella. Within the infected herds, 21-49% of the animals were infected. Few herds obtained high posterior estimates for the probability of freedom from infection given the collected data, with only six of 68 herds obtaining posterior probability of being infected less than 10%. Furthermore, this study indicated that serology is sufficiently sensitive and specific to be used for

  17. Short communication: Prevalence of methicillin resistance in coagulase-negative staphylococci and Staphylococcus aureus isolated from bulk milk on organic and conventional dairy farms in the United States.

    PubMed

    Cicconi-Hogan, K M; Belomestnykh, N; Gamroth, M; Ruegg, P L; Tikofsky, L; Schukken, Y H

    2014-05-01

    The objective of this study was to evaluate the presence of methicillin-resistant Staphylococcus aureus and coagulase-negative Staphylococcus spp. in bulk tank milk samples from 288 organic and conventional dairy farms located in New York, Wisconsin, and Oregon from March 2009 to May 2011. Due to recent publications reporting the presence mecC (a mecA homolog not detected by traditional mecA-based PCR methods), a combination of genotypic and phenotypic approaches was used to enhance the recovery of methicillin-resistant organisms from bulk tank milk. In total, 13 isolates were identified as methicillin resistant: Staph. aureus (n=1), Staphylococcus sciuri (n=5), Staphylococcus chromogenes (n=2), Staphylococcus saprophyticus (n=3), Staphylococcus agnetis (n=1), and Macrococcus caseolyticus (n=1). The single methicillin-resistant Staph. aureus isolate was identified from an organic farm in New York, for an observed 0.3% prevalence at the farm level. The methicillin-resistant coagulase-negative staphylococci prevalence was 2% in the organic population and 5% in the conventional population. We did not identify mecC in any of the isolates from our population. Of interest was the relatively high number of methicillin-resistant Staph. sciuri recovered, as the number of isolates from our study was considerably higher than those recovered from other recent studies that also assessed milk samples. Our research suggests that the presence of a potential methicillin-resistant Staphylococcus reservoir in milk, and likely the dairy farm population in the United States, is independent of the organic or conventional production system.

  18. Comparison of brown midrib-6 and -18 forage sorghum with conventional sorghum and corn silage in diets of lactating dairy cows.

    PubMed

    Oliver, A L; Grant, R J; Pedersen, J F; O'Rear, J

    2004-03-01

    Total mixed rations containing conventional forage sorghum, brown midrib (bmr)-6 forage sorghum, bmr-18 forage sorghum, or corn silage were fed to Holstein dairy cows to determine the effect on lactation, ruminal fermentation, and total tract nutrient digestion. Sixteen multiparous cows (4 ruminally fistulated; 124 d in milk) were assigned to 1 of 4 diets in a replicated Latin square design with 4-wk periods (21-d adaptation and 7 d of collection). Diets consisted of 40% test silage, 10% alfalfa silage, and 50% concentrate mix (dry basis). Acid detergent lignin concentration was reduced by 21 and 13%, respectively, for the bmr-6 and bmr-18 sorghum silages when compared with the conventional sorghum. Dry matter intake was not affected by diet. Production of 4% fat-corrected milk was greatest for cows fed bmr-6 (33.7 kg/d) and corn silage (33.3 kg/d), was least for cows fed the conventional sorghum (29.1 kg/d), and was intermediate for cows fed the bmr-18 sorghum (31.2 kg/d), which did not differ from any other diet. Total tract neutral detergent fiber (NDF) digestibility was greatest for the bmr-6 sorghum (54.4%) and corn silage (54.1%) diets and was lower for the conventional (40.8%) and bmr-18 sorghum (47.9%) diets. In situ extent of NDF digestion was greatest for the bmr-6 sorghum (76.4%) and corn silage (79.0%) diets, least for the conventional sorghum diet (70.4%), and intermediate for the bmr-18 sorghum silage diet (73.1%), which was not different from the other diets. Results of this study indicate that the bmr-6 sorghum hybrid outperformed the conventional sorghum hybrid; the bmr-18 sorghum was intermediate between conventional and bmr-6 in most cases. Additionally, the bmr-6 hybrid resulted in lactational performance equivalent to the corn hybrid used in this study. There are important compositional differences among bmr forage sorghum hybrids that need to be characterized to predict animal response accurately.

  19. DairyWise, a whole-farm dairy model.

    PubMed

    Schils, R L M; de Haan, M H A; Hemmer, J G A; van den Pol-van Dasselaar, A; de Boer, J A; Evers, A G; Holshof, G; van Middelkoop, J C; Zom, R L G

    2007-11-01

    A whole-farm dairy model was developed and evaluated. The DairyWise model is an empirical model that simulated technical, environmental, and financial processes on a dairy farm. The central component is the FeedSupply model that balanced the herd requirements, as generated by the DairyHerd model, and the supply of homegrown feeds, as generated by the crop models for grassland and corn silage. The output of the FeedSupply model was used as input for several technical, environmental, and economic submodels. The submodels simulated a range of farm aspects such as nitrogen and phosphorus cycling, nitrate leaching, ammonia emissions, greenhouse gas emissions, energy use, and a financial farm budget. The final output was a farm plan describing all material and nutrient flows and the consequences on the environment and economy. Evaluation of DairyWise was performed with 2 data sets consisting of 29 dairy farms. The evaluation showed that DairyWise was able to simulate gross margin, concentrate intake, nitrogen surplus, nitrate concentration in ground water, and crop yields. The variance accounted for ranged from 37 to 84%, and the mean differences between modeled and observed values varied between -5 to +3% per set of farms. We conclude that DairyWise is a powerful tool for integrated scenario development and evaluation for scientists, policy makers, extension workers, teachers and farmers.

  20. Steps can be taken to keep bovine viral diarrhea (BVD) out of your herd

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This is a review, written for a lay publication whose core audience in dairy producers. Control of BVD in any dairy operation must rely on the implementation of an organized strategy combining biosecurity, surveillance and increased herd resistance. This article discusses the design and implementati...

  1. Methane production, ruminal fermentation characteristics, nutrient digestibility, nitrogen excretion, and milk production of dairy cows fed conventional or brown midrib corn silage.

    PubMed

    Hassanat, F; Gervais, R; Benchaar, C

    2017-04-01

    The objective of this study was to examine the effect of replacing conventional corn silage (CCS) with brown midrib corn silage (BMCS) in dairy cow diets on enteric CH4 emission, nutrient intake, digestibility, ruminal fermentation characteristics, milk production, and N excretion. Sixteen rumen-cannulated lactating cows used in a crossover design (35-d periods) were fed (ad libitum) a total mixed ration (forage:concentrate ratio = 65:35, dry matter basis) based (59% dry matter) on either CCS or BMCS. Dry matter intake and milk yield increased when cows were fed BMCS instead of CCS. Of the milk components, only milk fat content slightly decreased when cows were fed the BMCS-based diet compared with when fed the CCS-based diet (3.81 vs. 3.92%). Compared with CCS, feeding BMCS to cows increased yields of milk protein and milk fat. Ruminal pH, protozoa numbers, total VFA concentration, and molar proportions of acetate and propionate were similar between cows fed BMCS and those fed CCS. Daily enteric CH4 emission (g/d) was unaffected by dietary treatments, but CH4 production expressed as a proportion of gross energy intake or on milk yield basis was lower for cows fed the BMCS-based diet than for cows fed the CCS-based diet. A decline in manure N excretion and a shift in N excretion from urine to feces were observed when BMCS replaced CCS in the diet, suggesting reduced potential of manure N volatilization. Results from this study show that improving fiber quality of corn silage in dairy cow diets through using brown midrib trait cultivar can reduce enteric CH4 emissions as well as potential emissions of NH3 and N2O from manure. However, CH4 emissions during manure storage may increase due to excretion of degradable OM when BMCS diet is fed, which merits further investigation.

  2. Optimization of methods for the detection of Mycobacterium avium subsp. paratuberculosis in milk and colostrum of naturally infected dairy cows with Johne's Disease

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mycobacterium avium subsp. paratuberculosis (MAP) is the causative agent of Johne’s Disease (JD), a chronic enteritis that occurs in dairy cattle and other ruminants. A 2007 NAHMS Dairy Study demonstrated that over 68% of dairy herds are infected with JD so the risk of exposure within a herd is high...

  3. Camelid herd health.

    PubMed

    Jones, Meredyth; Boileau, Melanie

    2009-07-01

    The area of herd health is particularly important when considering camelid operations because of the high frequency of travel for exhibition, breeding, and boarding. This article outlines the considerations for routine husbandry, facility and animal maintenance, and infectious disease control in the form of biosecurity, vaccination, and health testing that should be included in any farm's herd-health plan. Veterinary input into the design of programs for biosecurity and infectious disease prevention is critical and requires an active veterinary client-patient relationship with identification of the goals of the operation. Risk assessments should be made based on farm activities and should be the foundation for herd-health program design.

  4. Aligning health and welfare principles and practice in organic dairy systems: a review.

    PubMed

    Marley, C L; Weller, R F; Neale, M; Main, D C J; Roderick, S; Keatinge, R

    2010-02-01

    This review provides an assessment of research findings into the current practices and standards and the principles and aspirations for organic dairy production, with respect to the health and welfare of the dairy cow. The relationships between the four main factors: management, environment, genetics and nutrition and their impact on the health and welfare status of organic dairy cows are considered. The concept that good animal health and welfare is more than merely the absence of disease, with behavioural aspects of health and welfare such as physiological and psychological needs, is also discussed. These factors are inter-related and important in all dairy systems, irrespective of whether the system is organic, low-input or intensive. Incidences of individual clinical and sub-clinical diseases that are recorded in conventional dairy systems also occur in organic dairy systems, with infertility, lameness and mastitis being the major problems. However, the magnitude of the incidence of many of these diseases may be either lower or higher in organic systems due to different management practices and the standards defined for organic milk production that, for example, prohibit the routine use of conventional medicines and require the feeding of high-forage diets. In relation to different systems, it is important to note that contrary to a common assumption, good welfare does not necessarily occur with more extensive systems. The type of organic system (self-sufficient, purchased-feed) also has the potential to have a major influence on the incidence of health problems and the reproductive status of organic dairy herds. Health status is also influenced by environmental and welfare factors, including the method of rearing replacement animals, type of housing and the geographical and climatic conditions of individual farms. Overall, this review identifies where conflicts arise between current practice and the organic principles and standards, and aims to provide

  5. Effect of short-term versus long-term grassland management and seasonal variation in organic and conventional dairy farming on the composition of bulk tank milk.

    PubMed

    Adler, S A; Jensen, S K; Govasmark, E; Steinshamn, H

    2013-09-01

    Bulk tank milk from 28 dairy farms was sampled every second month for 2 yr to assess the effects of grassland management, production system and season on milk fatty acid (FA) composition, concentrations of fat-soluble vitamins, Se, and milk sensory quality. Grassland management varied in terms of time since establishment. Short-term grassland management (SG) was defined as establishment or reseeding every fourth year or more often, and long-term grassland management (LG) was defined as less frequent establishment or reseeding. Fourteen organic (ORG) dairy farms with either short-term or long-term grassland management were paired with 14 conventional (CON) farms with respect to grassland management. Within ORG farms, SG farms differed from LG farms in herbage botanical composition, but not in concentrate FA concentrations, dry matter intake, or milk yield. Within CON farms, herbage composition, concentrate FA concentrations, dry matter intake, and milk yield showed no or insignificant variations. The ORG farms differed from CON farms in herbage botanical composition, concentrate FA concentrations, concentrate intake, and milk yield. Compared with ORG-LG farms, ORG-SG farms produced milk fat with higher proportions of C10:0 and C12:0 associated with higher herbage proportions of legumes (Fabaceae) and lower proportions of other dicotyledon families. Compared with milk from CON farms, milk fat from ORG farms had higher proportions of most saturated FA and all n-3 FA, but lower proportions of C18:0 and C18:1 cis-9 associated with higher forage proportion and differences in concentrations of FA in concentrates. Compared with the outdoor-feeding periods, the indoor feeding periods yielded milk fat with higher proportions of most short-chain and medium-chain FA and lower proportions of most C18-FA associated with grazing and higher forage proportions. Milk concentrations of α-tocopherol and β-carotene were lower during the grazing periods. Inclusion of fishmeal in

  6. Vaccine herd effect.

    PubMed

    Kim, Tae Hyong; Johnstone, Jennie; Loeb, Mark

    2011-09-01

    Vaccination ideally protects susceptible populations at high risk for complications of the infection. However, vaccines for these subgroups do not always provide sufficient effectiveness. The herd effect or herd immunity is an attractive way to extend vaccine benefits beyond the directly targeted population. It refers to the indirect protection of unvaccinated persons, whereby an increase in the prevalence of immunity by the vaccine prevents circulation of infectious agents in susceptible populations. The herd effect has had a major impact in the eradication of smallpox, has reduced transmission of pertussis, and protects against influenza and pneumococcal disease. A high uptake of vaccines is generally needed for success. In this paper we aim to provide an update review on the herd effect, focusing on the clinical benefit, by reviewing data for specific vaccines.

  7. 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: ...

  8. Antimicrobial resistance in beef and dairy cattle production.

    PubMed

    Call, Douglas R; Davis, Margaret A; Sawant, Ashish A

    2008-12-01

    Observational studies of cattle production systems usually find that cattle from conventional dairies harbor a higher prevalence of antimicrobial resistant (AMR) enteric bacteria compared to organic dairies or beef-cow operations; given that dairies usually use more antimicrobials, this result is not unexpected. Experimental studies have usually verified that application of antimicrobials leads to at least a transient expansion of AMR bacterial populations in treated cattle. Nevertheless, on dairy farms the majority of antibiotics are used to treat mastitis and yet AMR remains relatively low in mastitis pathogens. Other studies have shown no correlation between antimicrobial use and prevalence of AMR bacteria including documented cases where the prevalence of AMR bacteria is non-responsive to antimicrobial applications or remains relatively high in the absence of antimicrobial use or any other obvious selective pressures. Thus, there are multi-factorial events and pressures that influence AMR bacterial populations in cattle production systems. We introduce a heuristic model that illustrates how repeated antimicrobial selection pressure can increase the probability of genetic linkage between AMR genes and niche- or growth-specific fitness traits. This linkage allows persistence of AMR bacteria at the herd level because subpopulations of AMR bacteria are able to reside long-term within the host animals even in the absence of antimicrobial selection pressure. This model highlights the need for multiple approaches to manage herd health so that the total amount of antimicrobials is limited in a manner that meets animal welfare and public health needs while reducing costs for producers and consumers over the long-term.

  9. Salmonella serotype shift during an endemic dairy infection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dairy farms are known reservoirs for Salmonella spp. and control of this organism is challenging. Salmonellae have been shown to be endemic in herds in part because they are easily spread between animals and throughout the farm environment. The impact of the infection on the herd is variable and dep...

  10. Modeling Tuberculosis Dynamics, Detection and Control in Cattle Herds

    PubMed Central

    Bekara, Mohammed El Amine; Courcoul, Aurélie; Bénet, Jean-Jacques; Durand, Benoit

    2014-01-01

    Epidemiological models are key tools for designing and evaluating detection and control strategies against animal infectious diseases. In France, after decades of decrease of bovine tuberculosis (bTB) incidence, the disease keeps circulating. Increasing prevalence levels are observed in several areas, where the detection and control strategy could be adapted. The objective of this work was to design and calibrate a model of the within-herd transmission of bTB. The proposed model is a stochastic model operating in discrete-time. Three health states were distinguished: susceptible, latent and infected. Dairy and beef herd dynamics and bTB detection and control programs were explicitly represented. Approximate Bayesian computation was used to estimate three model parameters from field data: the transmission parameter when animals are inside (βinside) and outside (βoutside) buildings, and the duration of the latent phase. An independent dataset was used for model validation. The estimated median was 0.43 [0.16–0.84] month−1 for βinside and 0.08 [0.01–0.32] month−1 for βoutside. The median duration of the latent period was estimated 3.5 [2]–[8] months. The sensitivity analysis showed only minor influences of fixed parameter values on these posterior estimates. Validation based on an independent dataset showed that in more than 80% of herds, the observed proportion of animals with detected lesions was between the 2.5% and 97.5% percentiles of the simulated distribution. In the absence of control program and once bTB has become enzootic within a herd, the median effective reproductive ratio was estimated to be 2.2 in beef herds and 1.7 in dairy herds. These low estimates are consistent with field observations of a low prevalence level in French bTB-infected herds. PMID:25254369

  11. Persistence of plant DNA sequences in the blood of dairy cows fed with genetically modified (Bt176) and conventional corn silage.

    PubMed

    Bertheau, Y; Helbling, J C; Fortabat, M N; Makhzami, S; Sotinel, I; Audéon, C; Nignol, A C; Kobilinsky, A; Petit, L; Fach, P; Brunschwig, P; Duhem, K; Martin, P

    2009-01-28

    To determine whether plant sequences, including transgenic sequences, are present in animal blood, we tested blood samples from Holstein cows fed with either Bt176 genetically modified corn or conventional corn. We used previously described sensitive real-time PCR assays targeting transgenic sequences (35S promoter and Bt176 specific junction sequence), a monocopy maize-specific sequence (ADH promoter), and two multicopy sequences from plant nucleus (26S rRNA gene) and chloroplast (psaB gene). The presence of Cry1A(b) protein in bovine blood samples was also tested using a sandwich ELISA kit. Our study shows the ability of plant nuclear and/or chloroplast DNA fragments to enter bovine blood circulation. However, maize nuclear DNA, both mono- and multicopy sequences, was less detected than chloroplast DNA, probably because the higher number of chloroplast copies and also possibly because nuclear DNA might be less protected by the nuclear membrane. Despite our data confirm the ability of small (ca.150 bp) plant DNA fragments to cross the intestinal barrier, we were unable to demonstrate clearly the presence of transgenic DNA or proteins in bovine blood. No sample tested positive with the two real-time PCR assays targeting transgenic sequences (35S promoter and Bt176 specific junction sequence). Only faint punctual positive results occurred randomly and were probably due to postsample collection or laboratory contamination or can be considered as artifact as they have never been confirmed. Our data highlight the difficulties to detect transgenic sequences in blood of dairy cows fed genetically modified corn (Bt176) silage. Those results show that in order to meet the consumers' demand of animals fed with GM products there is currently no cost-effective analytical procedure to replace documentary traceability.

  12. Hot topic: Comparison of sex-sorted and conventional semen within a fixed-time artificial insemination protocol designed for dairy heifers.

    PubMed

    Mallory, D A; Lock, S L; Woods, D C; Poock, S E; Patterson, D J

    2013-02-01

    The objective was to compare pregnancy per AI (P/AI) with conventional (CON) or sex-sorted (SS) semen from a single sire within a fixed-time AI (FTAI) program designed for dairy heifers. Holstein heifers (n=240) were assigned to treatment (CON or SS) according to body weight and reproductive tract score. All heifers underwent FTAI by using the "Show-Me-Synch" protocol [controlled internal drug release (CIDR) insert from d 0 to 14 followed by PGF(2α) (25mg i.m.) 16d after insert removal (d 30) with GnRH (100 µg i.m.) and FTAI at 66 h after PGF(2α)]. A single professional technician performed the FTAI. Heifers were fitted with heat detection patches at PGF(2α) to characterize estrous response. Estrous response did not differ between CON (63/120; 53%) and SS (70/120; 58%) treatments. The CON heifers, however, achieved greater FTAI P/AI (82/120; 68%) compared with SS (45/120; 38%) heifers. The P/AI did not differ for CON heifers that exhibited or failed to exhibit estrus before FTAI [44/63 (70%) vs. 38/57(67%), respectively]. For SS heifers, however, those that exhibited estrus had greater P/AI compared with those that failed to exhibit estrus [32/70 (46%) vs. 13/50 (26%)]. Pregnancy per AI resulting from FTAI was greater for heifers that were inseminated with CON semen compared with those that received SS semen. The expression of estrus before FTAI did not affect P/AI when CON semen was used, whereas the P/AI with SS semen was greater for heifers detected in estrus. Further studies are required to develop strategies for using sex-sorted semen when inseminating heifers at predetermined fixed times on the basis of expression of estrus before FTAI.

  13. Indirect effects by meningococcal vaccines: herd protection versus herd immunity.

    PubMed

    Bröker, Michael

    2011-08-01

    The term "herd immunity" for the indirect effect of meningococcal conjugate vaccines is inaccurate. A more appropriate term is "herd protection," because this term correctly describes the public effects imparted by vaccination campaigns against the meningococcus.

  14. Understanding Herd Immunity.

    PubMed

    Metcalf, C J E; Ferrari, M; Graham, A L; Grenfell, B T

    2015-12-01

    Individual immunity is a powerful force affecting host health and pathogen evolution. Importantly, the effects of individual immunity also scale up to affect pathogen transmission dynamics and the success of vaccination campaigns for entire host populations. Population-scale immunity is often termed 'herd immunity'. Here we outline how individual immunity maps to population outcomes and discuss implications for control of infectious diseases. Particular immunological characteristics may be more or less likely to result in a population level signature of herd immunity; we detail this and also discuss other population-level outcomes that might emerge from individual-level immunity.

  15. Reduced medication in organic farming with emphasis on organic dairy production.

    PubMed

    Vaarst, M; Bennedsgaard, T W

    2001-01-01

    Medication is an important focus area in organic animal husbandry. The combination of goals relating to improved animal welfare and reduced use of chemicals in general creates a common wish to reduce medication. Based on data from current Danish research projects in organic dairy farming, one specific organic medication pattern or policy cannot be described. The disease treatment pattern is influenced by many factors, e.g. the interaction with colleagues, veterinarians and agricultural advisors. No significant difference could be found with regard to incidence of mastitis treatments or somatic cell counts in 27 organic and 57 conventional herds. A marked tendency to shorter treatment periods in relation to mastitis treatments was described for organic farms in comparison with conventional farms (1.9 days versus 3.2 days (5 organic and 7 conventional herds)). In a study of development of health advisory service in organic herds, the dialogue between farmer, veterinarian and agricultural cattle advisor changed the treatment pattern markedly during a period of 6 months. Among important future challenges for veterinarians in organic farming is pointed at the constructive, open, and critical interaction with the single organic farmer as well as the organic animal husbandry system in general.

  16. Specific pathogen-free pig herds also free from Campylobacter?

    PubMed

    Kolstoe, E M; Iversen, T; Østensvik, Ø; Abdelghani, A; Secic, I; Nesbakken, T

    2015-03-01

    As Specific Pathogen-Free (SPF) pig herds are designed and managed to prevent specific pig diseases, it might be feasible to expand the list of micro-organisms also including zoonotic pathogens such as Campylobacter coli as this agent has its origin in pigs. In a previous survey, 15 of 16 of SPF herds were found free from human pathogenic Yersinia enterocolitica. Accordingly, three nucleus and seven multiplying herds were surveyed for Campylobacter to investigate whether the Norwegian SPF pig pyramid also might be free from this agent. In conclusion, the intervention of Campylobacter at the herd level might be possible as four of 10 SPF herds tested negative in two sets of samples from both autumn 2008 and summer/early autumn 2010. The four negative herds were all located in remote areas several kilometres away from conventional pig farming while the positive SPF farms were all situated in neighbourhoods with conventional pig production. It seems more difficult to control Campylobacter than some specific animal disease agents and another significant zoonotic agent, Y. enterocolitica, in pig herds.

  17. HACCP-based quality risk management approach to udder health problems on dairy farms

    PubMed Central

    2009-01-01

    Against the background of prevailing udder health problems on dairy farms, this paper discusses a new approach to mastitis control. Current udder health control programmes, such as the 'five-point plan', are highlighted and their drawbacks indicated. The concept and principles of hazard analysis critical control points (HACCP) are introduced. The eight core elements of this concept are dealt with by using the example of a dairy herd with a mastitis problem due to Staphylococcus aureus. The various steps to be taken in the development of a HACCP-based quality risk management programme are illustrated through the application of core elements. Finally, it is shown that the HACCP key words, structure, organisation, planning, communication and formalisation; which do not frequently appear in conventional herd health and production management programmes can contribute to better udder health. The role of the veterinarian can be paramount and of added value, if he/she is willing to invest in new knowledge and skills, such as the HACCP concept, farm economics, animal nutrition, and particularly the role of coach to the dairy farmer in the implementation of preventative measures in relation to udder health. PMID:22082372

  18. HACCP-based quality risk management approach to udder health problems on dairy farms.

    PubMed

    Noordhuizen, Jptm; Cannas da Silva, J

    2009-04-01

    Against the background of prevailing udder health problems on dairy farms, this paper discusses a new approach to mastitis control. Current udder health control programmes, such as the 'five-point plan', are highlighted and their drawbacks indicated. The concept and principles of hazard analysis critical control points (HACCP) are introduced. The eight core elements of this concept are dealt with by using the example of a dairy herd with a mastitis problem due to Staphylococcus aureus. The various steps to be taken in the development of a HACCP-based quality risk management programme are illustrated through the application of core elements. Finally, it is shown that the HACCP key words, structure, organisation, planning, communication and formalisation; which do not frequently appear in conventional herd health and production management programmes can contribute to better udder health. The role of the veterinarian can be paramount and of added value, if he/she is willing to invest in new knowledge and skills, such as the HACCP concept, farm economics, animal nutrition, and particularly the role of coach to the dairy farmer in the implementation of preventative measures in relation to udder health.

  19. Strategies used by dairy family farmers in the south of Brazil to comply with organic regulations.

    PubMed

    Honorato, L A; Machado Filho, L C P; Barbosa Silveira, I D; Hötzel, M J

    2014-03-01

    The aims of this study were to investigate the environmental, feeding, and health management of organic (ORG) family dairy farms in the south of Brazil in comparison with conventional (CONV) farms, and to assess their degree of compliance with Brazilian organic legislation and the strategies they adopt to accomplish this (n=17 per group). During 2 visits to each farm in March and September, 2010, observations were made on the environment, feed, and health management, followed by bulk milk testing, clinical evaluation, and breed assessment of each individual cow, and an evaluation of diseases and treatments reported within the period. Additional data were collected directly from the farmers through direct interviews. The number of lactating cows was, on average, 11 (range 5 to 19) in the ORG and 16 (range 7 to 42) in the CONV herds. The ORG herds presented a lower percentage of the Holstein breed; whereas CONV herds were predominantly Holstein, in the ORG herds, only 2 herds were 100% Holstein and the remaining herds were crosses of Holstein, Jersey, and Gir (Bos indicus) cattle. Milk production per cow was lower (10.2 vs. 15.1 ± 1.22 L/cow, respectively) in ORG than in the CONV farms. The ORG farms offered less concentrate feed than CONV farms and had better pasture management. Organic farmers reported using phytotherapic and homeopathic products, and pasture management as a strategy to keep infection levels of endo- and ectoparasites low, whereas CONV farmers regularly used anthelmintics and acaricides. Milk production was lower in ORG than in CONV farms, but cow health and condition scores were broadly similar, indicating that the with these strategies ORG farms were able to secure levels of animal welfare comparable with CONV farms while complying with organic regulation, although at the cost of lower cow productivity.

  20. The optimal number of heifer calves to be reared as dairy replacements.

    PubMed

    Mohd Nor, N; Steeneveld, W; Mourits, M C M; Hogeveen, H

    2015-02-01

    Dairy farmers often keep almost all their newborn heifer calves despite the high cost of rearing. By rearing all heifer calves, farmers have more security and retain flexibility to cope with the uncertainty in the availability of replacement heifers in time. This uncertainty is due to mortality or infertility during the rearing period and the variation in culling rate of lactating cows. The objective of this study is to provide insight in the economically optimal number of heifer calves to be reared as replacements. A herd-level stochastic simulation model was developed specific for this purpose with a herd of 100 dairy cows; the biological part of the model consisted of a dairy herd unit and rearing unit for replacement heifers. The dairy herd unit included variation in the number of culled dairy cows. The rearing unit incorporated variation in the number of heifers present in the herd by including uncertainty in mortality and variation in fertility. The dairy herd unit and rearing unit were linked by the number of replacement heifers and culled dairy cows. When not enough replacement heifers were available to replace culled dairy cows, the herd size was temporarily reduced, resulting in an additional cost for the empty slots. When the herd size reached 100 dairy cows, the available replacement heifers that were not needed were sold. It was assumed that no purchase of cows and calves occurred. The optimal percentage of 2-wk-old heifer calves to be retained was defined as the percentage of heifer calves that minimized the average net costs of rearing replacement heifers. In the default scenario, the optimal retention was 73% and the total net cost of rearing was estimated at €40,939 per herd per year. This total net cost was 6.5% lower than when all heifer calves were kept. An earlier first-calving age resulted in an optimal retention of 75%, and the net costs of rearing were €581 per herd per year lower than in the default scenario. For herds with a lower or

  1. Using herd records to monitor transition cow survival, productivity, and health.

    PubMed

    Nordlund, Kenneth V; Cook, Nigel B

    2004-11-01

    There is no single monitor that can fully characterize the success of a transition cow management program in a herd. Rather we must rely on a group of key monitors. Table 5 outlines the key indices and targets that we use in herd investigations. By using these monitors, effective transition cow programs can be differentiated from problematic ones, and many of the problems can be resolved for the good of the herd owners, dairy laborers, and most of all, the cows. Development of more sophisticated monitors and software with stronger epidemiologic structure will allow for better analysis of programs in the future.

  2. 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.

  3. 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

  4. Relationship between dairy cow genetic merit and profit on commercial spring calving dairy farms.

    PubMed

    Ramsbottom, G; Cromie, A R; Horan, B; Berry, D P

    2012-07-01

    Because not all animal factors influencing profitability can be included in total merit breeding indices for profitability, the association between animal total merit index and true profitability, taking cognisance of all factors associated with costs and revenues, is generally not known. One method to estimate such associations is at the herd level, associating herd average genetic merit with herd profitability. The objective of this study was to primarily relate herd average genetic merit for a range of traits, including the Irish total merit index, with indicators of performance, including profitability, using correlation and multiple regression analyses. Physical, genetic and financial performance data from 1131 Irish seasonal calving pasture-based dairy farms were available following edits; data on some herds were available for more than 1 year of the 3-year study period (2007 to 2009). Herd average economic breeding index (EBI) was associated with reduced herd average phenotypic milk yield but with greater milk composition, resulting in higher milk prices. Moderate positive correlations (0.26 to 0.61) existed between genetic merit for an individual trait and average herd performance for that trait (e.g. genetic merit for milk yield and average per cow milk yield). Following adjustment for year, stocking rate, herd size and quantity of purchased feed in the multiple regression analysis, average herd EBI was positively and linearly associated with net margin per cow and per litre as well as gross revenue output per cow and per litre. The change in net margin per cow per unit change in the total merit index was €1.94 (s.e. = 0.42), which was not different from the expectation of €2. This study, based on a large data set of commercial herds with accurate information on profitability and genetic merit, confirms that, after accounting for confounding factors, the change in herd profitability per unit change in herd genetic merit for the total merit index is

  5. 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

  6. The association of high and low parent average with daughter performance for yield, somatic cell score, and productive life in individual herds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    There have been efforts to demonstrate to dairy producers the value of genetic selection by evaluating response to selection within their own herds. The objective of this study was to evaluate how frequently results conform to expectations for various traits and for herds of varying sizes. Parent av...

  7. Assessing the impact of natural service bulls and genotype by environment interactions on genetic gain and inbreeding in organic dairy cattle genomic breeding programs.

    PubMed

    Yin, T; Wensch-Dorendorf, M; Simianer, H; Swalve, H H; König, S

    2014-06-01

    The objective of the present study was to compare genetic gain and inbreeding coefficients of dairy cattle in organic breeding program designs by applying stochastic simulations. Evaluated breeding strategies were: (i) selecting bulls from conventional breeding programs, and taking into account genotype by environment (G×E) interactions, (ii) selecting genotyped bulls within the organic environment for artificial insemination (AI) programs and (iii) selecting genotyped natural service bulls within organic herds. The simulated conventional population comprised 148 800 cows from 2976 herds with an average herd size of 50 cows per herd, and 1200 cows were assigned to 60 organic herds. In a young bull program, selection criteria of young bulls in both production systems (conventional and organic) were either 'conventional' estimated breeding values (EBV) or genomic estimated breeding values (GEBV) for two traits with low (h 2=0.05) and moderate heritability (h 2=0.30). GEBV were calculated for different accuracies (r mg), and G×E interactions were considered by modifying originally simulated true breeding values in the range from r g=0.5 to 1.0. For both traits (h 2=0.05 and 0.30) and r mg⩾0.8, genomic selection of bulls directly in the organic population and using selected bulls via AI revealed higher genetic gain than selecting young bulls in the larger conventional population based on EBV; also without the existence of G×E interactions. Only for pronounced G×E interactions (r g=0.5), and for highly accurate GEBV for natural service bulls (r mg>0.9), results suggests the use of genotyped organic natural service bulls instead of implementing an AI program. Inbreeding coefficients of selected bulls and their offspring were generally lower when basing selection decisions for young bulls on GEBV compared with selection strategies based on pedigree indices.

  8. Characterization of Dutch dairy farms using sensor systems for cow management.

    PubMed

    Steeneveld, W; Hogeveen, H

    2015-01-01

    To improve cow management in large dairy herds, sensors have been developed that can measure physiological, behavioral, and production indicators on individual cows. Recently, the number of dairy farms using sensor systems has increased. It is not known, however, to what extent sensor systems are used on dairy farms, and the reasons why farmers invest or not in sensor systems are unclear. The first objective of this study was to give an overview of the sensor systems currently used in the Netherlands. The second objective was to investigate the reasons for investing or not investing in sensor systems. The third objective was to characterize farms with and without sensor systems. A survey was developed to investigate first, the reasons for investing or not in sensor systems and, then, how the sensor systems are used in daily cow management. The survey was sent to 1,672 Dutch dairy farmers. The final data set consisted of 512 dairy farms (response rate of 30.6%); 202 farms indicated that they had sensor systems and 310 farms indicated that they did not have sensor systems. A wide variety of sensor systems was used on Dutch dairy farms; those for mastitis detection and estrus detection were the most-used sensor systems. The use of sensor systems was different for farms using an automatic milking system (AMS) and a conventional milking system (CMS). Reasons for investing were different for different sensor systems. For sensor systems attached to the AMS, the farmers made no conscious decision to invest: they answered that the sensors were standard in the AMS or were bought for reduced cost with the AMS. The main reasons for investing in estrus detection sensor systems were improving detection rates, gaining insights into the fertility level of the herd, improving profitability of the farm, and reducing labor. Main reasons for not investing in sensor systems were economically related. It was very difficult to characterize farms with and without sensor systems. Farms

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

    2009-04-01

    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.

  10. Dairy Wastes.

    ERIC Educational Resources Information Center

    Pico, Richard F.

    1978-01-01

    Presents a literature review of wastes from the dairy industry covering publications of 1976-77. This review covers: (1) government regulations; (2) ion-plant control of dairy effluents; (3) dairy effluent treatment methods; and (4) research on dairy effluents. A list of 26 references is also presented. (HM)

  11. The Effect of Wind on Coxiella burnetii Transmission Between Cattle Herds: a Mechanistic Approach.

    PubMed

    Nusinovici, S; Hoch, T; Brahim, M L; Joly, A; Beaudeau, F

    2017-04-01

    There is a consensus that wind plays a key role in the transmission of Coxiella burnetii, the causative agent of Q fever, between ruminants and from ruminants to humans. However, no observational study so far has focused on the mechanisms associated with this airborne transmission. This study applied a mechanistic epidemiological approach to investigate the processes underlying the wind effect and to assess its influence on the risk for a dairy herd to become C. burnetii infected. Ninety-five dairy cattle herds located in the Finistère department (western France) were subjected to samplings of bulk tank milk and indoor dust every 4 months over a 1-year period to determine their C. burnetii status using PCR tests. A total of 27 incident herd-periods (negative-tested on both PCR tests and becoming positive-tested at least once at the subsequent sampling time) and 71 negative herd-periods were retained for analysis. Using logistic regression, we assessed the effect of (i) the cumulated number of bacteria in herds located under the main wind direction and (ii) the mean wind speed in this area, on a given herd's risk of becoming incident. Compared to herds in areas with low wind speed (≤5.5 m/s), the risk was significantly higher (OR = 3.7) in herds in areas with high wind speed (>5.5 m/s) and high bacterial load (>10), whereas it was not significantly different from unity in other situations. In agreement with our assumptions, C. burnetii transmission to a previously infection-free herd occurs only when (i) the wind transporting from infected sources and (ii) the load in the contaminated particles/aerosols generated are high enough to act jointly.

  12. Reduction of the abortion rate due to Toxoplasma in 3 goat herds following administration of sulfadimidine

    PubMed Central

    Giadinis, Nektarios D.; Lafi, Shawkat Q.; Ioannidou, Evi; Papadopoulos, Elias; Terpsidis, Konstantinos; Karanikolas, George; Petridou, Evanthia J.; Brozos, Christos; Karatzias, Harilaos

    2013-01-01

    The efficacy of sulfadimidine (4 doses of 33 mg/kg body weight, IM, q48h) against Toxoplasma abortion was assessed in 3 dairy goat herds suffering from Toxoplasma abortions during the 4th month of gestation. This protocol was very effective for the control of Toxoplasma abortions (P < 0.01). PMID:24179245

  13. Association between the level of antibodies in bulk tank milk and bovine respiratory syncytial virus exposure in the herd

    PubMed Central

    Klem, T. B.; Tollersrud, T.; Østerås, O.; Stokstad, M.

    2014-01-01

    Antibody levels in bulk tank milk (BTM) against bovine respiratory syncytial virus (BRSV) are used to classify BRSV status of herds. The aim of this study was to investigate how these levels correspond with the time at which the herds were infected. Bulk tank milk, individual milk and serum samples from cows and young stock were investigated using an indirect ELISA. Screenings of BTM from 89 dairy herds during two winter seasons revealed a prevalence of positive herds from 82 per cent to 85 per cent. Eleven herds showed a marked increase in antibody levels between two screenings, indicating new infection. However, two of these herds had been free from BRSV for the last five to seven years. Two newly infected herds were monitored for four years and did not appear to get reinfected. Surprisingly, the BTM antibody levels in these herds remained high throughout the study period, but fluctuated significantly. This shows that the levels of antibodies in BTM can remain high for several years, even in herds where reinfection does not occur. BTM serology is a useful tool in the monitoring of infectious diseases in dairy herds, but has limitations as a diagnostic tool for BRSV infections. PMID:24864076

  14. The environmental impact of dairy production: 1944 compared with 2007.

    PubMed

    Capper, J L; Cady, R A; Bauman, D E

    2009-06-01

    A common perception is that pasture-based, low-input dairy systems characteristic of the 1940s were more conducive to environmental stewardship than modern milk production systems. The objective of this study was to compare the environmental impact of modern (2007) US dairy production with historical production practices as exemplified by the US dairy system in 1944. A deterministic model based on the metabolism and nutrient requirements of the dairy herd was used to estimate resource inputs and waste outputs per billion kg of milk. Both the modern and historical production systems were modeled using characteristic management practices, herd population dynamics, and production data from US dairy farms. Modern dairy practices require considerably fewer resources than dairying in 1944 with 21% of animals, 23% of feedstuffs, 35% of the water, and only 10% of the land required to produce the same 1 billion kg of milk. Waste outputs were similarly reduced, with modern dairy systems producing 24% of the manure, 43% of CH(4), and 56% of N(2)O per billion kg of milk compared with equivalent milk from historical dairying. The carbon footprint per billion kilograms of milk produced in 2007 was 37% of equivalent milk production in 1944. To fulfill the increasing requirements of the US population for dairy products, it is essential to adopt management practices and technologies that improve productive efficiency, allowing milk production to be increased while reducing resource use and mitigating environmental impact.

  15. Identification of potential sources of Staphylococcus aureus in herds with mastitis problems.

    PubMed

    Capurro, A; Aspán, A; Ericsson Unnerstad, H; Persson Waller, K; Artursson, K

    2010-01-01

    Staphylococcus aureus is a common udder pathogen of dairy cows that often causes herd problems. Various mastitis control programs have been used to combat the problem but have not always been efficient in preventing new Staph. aureus infections, indicating the presence of possible sources of infection other than those traditionally considered. Therefore, the aim of the study was to identify potential sources of infection relevant for Staph. aureus mastitis within 5 dairy herds with udder health problems caused by Staph. aureus. Samples were collected from milk of lactating cows, from body sites, and from the environment of lactating cows, dry cows, late pregnant heifers, young heifers 4 to 12 mo old, and heifer calves 0 to 3 mo old. Isolates of Staph. aureus were identified and compared using pulsed-field gel electrophoresis. Four to 7 unique Staph. aureus pulsotypes were found within each herd, with one strain predominating in milk in each herd. The milk pulsotypes were also frequently isolated in body samples, especially on hock skin, and in the immediate environment of lactating cows, and were sometimes found in other animal groups, especially in dry cows and heifer calves 0 to 3 mo old. The prevalence of Staph. aureus in milk and other types of samples varied markedly between herds. Staphylococcus aureus isolates with genotypes indistinguishable from those found in milk also dominated in extra-mammary sites within the dairy herds studied, and hock skin was identified as an important reservoir of Staph. aureus. The results contribute new knowledge necessary to improve strategies for udder health control in herds.

  16. 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).

  17. The diagnostic performance of an antibody enzyme-linked immunosorbent assay using serum and colostrum to determine the disease status of a Jersey dairy herd infected with Mycobacterium avium subspecies paratuberculosis.

    PubMed

    Jenvey, Caitlin J; Reichel, Michael P; Cockcroft, Peter D

    2016-01-01

    Colostrum may have the ability to improve the diagnostic accuracy of some tests when compared to serum for important livestock diseases because of the high concentrations of immunoglobulins present within this sample type. The ELISA for Johne's disease is one such test, as it suffers from low sensitivity when testing serum samples collected during the subclinical stage of infection. Blood and colostrum samples were collected from 34 Jersey dairy cows and tested for antibodies against Mycobacterium avium subspecies paratuberculosis (MAP) by ELISA. Fecal samples were also collected and tested by a high-throughput Johne's polymerase chain reaction (HT-J PCR) assay and fecal culture (FC), with the latter being used as the reference test. A receiver operating characteristic (ROC) analysis was performed, and the area under the curve (AUC) was calculated. The HT-J PCR and FC results were also compared. Of the 34 cows in this study, 4 had FC results consistent with MAP infection. The HT-J PCR did not identify any FC-positive cows. Using a 1:20 dilution and sample-to-positive (S/P) ratio cutoff threshold of 0.15, the relative sensitivity values of both serum (AUC 0. 56) and colostrum (AUC 0.63) were 0%. With lower sample dilutions, the relative sensitivity values of serum were 0% (1:2, AUC 0.62; 1:5, AUC 0.55); however, the relative sensitivity value of colostrum was 75% (95% confidence interval [CI]: 19-99%) at a dilution of 1:5, S/P ratio cutoff threshold of 0.15, and AUC of 0.73 (95% CI: 0.55-0.87). The testing of colostrum samples for MAP-specific antibodies by ELISA may provide improved identification of animals in the early stages of infection with MAP when compared with serum samples.

  18. Within- and between-herd prevalence variation of Mycobacterium avium subsp. paratuberculosis infection among control programme herds in Denmark (2011-2013).

    PubMed

    Verdugo, Cristobal; Toft, Nils; Nielsen, Søren Saxmose

    2015-10-01

    This study aimed to estimate the between- (HTP) and within- (TP) herd true prevalence distribution of Mycobacterium avium subsp. paratuberculosis (MAP) infection in dairy cattle herds participating in the Danish MAP control programme. All herds enrolled in the programme between 2011 and 2013 were included in the analysis, and one annual milk-ELISA test of all lactating cows present in such herds was considered. A Bayesian latent class model was used to obtain HTP and TP posterior distributions for each year. The model adjusts for uncertainty in age-specific test sensitivity and prior prevalence estimates. Bayesian posterior probabilities were computed in order to compare prevalence between the years. A total of 665,700 samples were included in the study, from 221,914, 224,040, and 220,466 cows sourced from 1138, 1112, and 1059 herds in years 2011, 2012, and 2013, respectively. In that period, HTP estimates of 0.92 (95% posterior probability interval (PPI), 0.87-0.96), 0.78 (95% PPI, 0.74-0.83), and 0.75 (95% PPI, 0.71-0.78) were recorded, respectively. Low TP were observed, with population mean estimates of 0.08 (95% PPI, 0.07-0.08), 0.07 (95% PPI, 0.07-0.08), and 0.07 (95% PPI, 0.06-0.07) for the three consecutive years. Statistically-important differences were recorded for HTP and population mean TP estimates between years, indicating a trend for a decreasing level of MAP infection at both herd and animal level. Model results showed that MAP infection was widespread among the Dairy cattle herds participating in the Danish control programme, though in general it was kept at very low levels.

  19. Bovine herpesvirus 1: within-herd seroprevalence and antibody levels in bulk-tank milk.

    PubMed

    Martínez, S; Yus, E; Sanjuán, M L; Camino, F; Eiras, M C; Arnaiz, I; Diéguez, F J

    2016-12-01

    The aim of the present study was to establish a relationship between the results obtained with the enzyme-linked immunosorbent assay (ELISA) technique for antibodies (against bovine herpesvirus 1) in serum and those in milk at the herd level. For this purpose, 275 samples of bulk-tank milk were analysed with glycoprotein E (gE) antibody ELISA and 207 more were analysed with glycoprotein B (gB) antibody ELISA (482 in total). All of these samples came from dairy herds whose seroprevalence was also evaluated. The results of this study were then used to analyse the sensitivity of the bulk-tankmilk test in detecting herds with a high risk of active infection (>60% seroprevalence) and its specificity in detecting those with few (<20%) or no seropositive animals. In regard to the reference test (results in blood serum), the sensitivity of the bulk-tankmilk test in detecting herds with >60% seropositive animals was 100% for both gE and gB ELISAs. The specificity figures, for gE and gB ELISAs, respectively, were 88.4% and 99.1% for infection-free herds and 72.6% and 96% for herds with <20% seroprevalence. In a quantitative approach, Pearson's correlation coefficients, reported as a measure of linear association between herd seroprevalences and transformed optical density values recorded in bulk-tank milk, were -0.63 for gE ELISA and 0.67 for gB ELISA.

  20. The economics of dairy production.

    PubMed

    Wolf, Christopher A

    2003-07-01

    The structure of the dairy farm industry has been changing rapidly in recent years. Milk production has increased, with dramatic increases in milk produced per cow and with a steep decline in number of milk cows and fewer farms with larger herds. The change in dairy farm size has not been uniform across regions. The growth in farm size has occurred much more rapidly in the Pacific and South regions than in the traditional dairy-producing regions (Upper Midwest, Northeast, and Corn Belt). Using USDA data to examine costs and returns over time reveals that the incentives to produce milk have been much greater in the Pacific and South regions in recent years. Although the cash costs are similar across regions, accounting for all costs including unpaid factors such as labor and capital replacement yields a clear advantage for the Pacific region. Dairy farm size and cost of production are jointly determined. The incentive to increase farm size is derived from the economies of size that may be achieved by spreading the capital, labor, and managerial costs across more units of milk production. Empiric evidence from previous studies indicates a declining cost of production over a large range of herd sizes. Even in the presence of a flat average cost curve, the incentive to maximize farm income provides incentive to increase production. Adjustment costs may fix dairy production facilities in their current use. Those firms facing higher adjustment costs because of individual or regional characteristics or because of different timing of growth will be smaller or grow more slowly than if they faced smaller adjustment costs. This situation may explain the continued lag of farm size and technology adoption in the traditional dairy producing regions relative to the Pacific and South regions where the more recent population growth coincided with the presence of modern, large-scale production technologies. Finally, dairy marketing policies almost certainly have affected the

  1. 9 CFR 55.24 - Herd status.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... available for testing (i.e., a trace animal from a known positive herd died and was not tested) or for other... with program requirements for animal identification, animal testing, and recordkeeping, the herd will... requirements of the CWD Herd Certification Program. The herd plan will require testing of all animals that...

  2. 9 CFR 55.24 - Herd status.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... available for testing (i.e., a trace animal from a known positive herd died and was not tested) or for other... with program requirements for animal identification, animal testing, and recordkeeping, the herd will... requirements of the CWD Herd Certification Program. The herd plan will require testing of all animals that...