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1

Development of a Lifetime Merit-based selection index for US dairy grazing systems.  

PubMed

Pasture-based dairy producers in the United States face costs, revenue streams, and management challenges that may differ from those associated with confinement dairy production systems. Three Grazing Merit indices (GM$1, GM$2, and GM$3), parallel to the US Lifetime Net Merit (NM$) index, were constructed using economic values appropriate for grazing production in the United States. Milk prices based on averages from the previous 5 yr were used for GM$1, whereas GM$2 and GM$3 used milk prices found in NM$. Cull prices and interest rates from NM$ were used in GM$3 but were updated for GM$1 and GM$2. All other inputs remained constant among GM$1, GM$2, and GM$3. Economic costs and revenues were obtained from surveys, recent literature, and farm financial record summaries. Derived weights for GM$ were then multiplied by the predicted transmitting abilities of 584 active artificial insemination Holstein bulls to compare with NM$. Spearman rank correlations for NM$ were 0.93 with GM$1, 0.98 with GM$2, and 0.98 with GM$3. Traits (and their percentages of weight) comprising GM$1, GM$2, and GM$3, respectively, included milk volume (24, 0, 0%), Fat yield (16, 21, 21%), protein yield (4, 17, 17%), productive life (7, 8, 7%), somatic cell count (-8, -9, -9%), feet and legs composite (4, 4, 4%), body size composite (-3, -4, -4%), udder composite (7, 8, 8%), daughter pregnancy rate (18, 20, 20%), calving ability (3, 3, 3%), and dairy form (6, 6, 6%). These weights compared with NM$ weights of 0, 19, 16, 22, 10, 4, 6, 7, 11, 5, and 0% for the same traits, respectively. Dairy form was added to GM$ to offset the decrease in strength associated with selection to reduce stature through selection against body size. Emphasis on productive life decreased in GM$ because grazing cattle are estimated to remain in the herd considerably longer, diminishing the marginal value of productive life. Although NM$ provides guidance for grazing dairy producers, a GM$ index based upon appropriate costs and revenues allows for selection of cows and bulls for more optimal genetic progress. PMID:24792796

Gay, K D; Widmar, N J O; Nennich, T D; Schinckel, A P; Cole, J B; Schutz, M M

2014-07-01

2

e-Dairy: a dynamic and stochastic whole-farm model that predicts biophysical and economic performance of grazing dairy systems.  

PubMed

A whole-farm, stochastic and dynamic simulation model was developed to predict biophysical and economic performance of grazing dairy systems. Several whole-farm models simulate grazing dairy systems, but most of them work at a herd level. This model, named e-Dairy, differs from the few models that work at an animal level, because it allows stochastic behaviour of the genetic merit of individual cows for several traits, namely, yields of milk, fat and protein, live weight (LW) and body condition score (BCS) within a whole-farm model. This model accounts for genetic differences between cows, is sensitive to genotype × environment interactions at an animal level and allows pasture growth, milk and supplements price to behave stochastically. The model includes an energy-based animal module that predicts intake at grazing, mammary gland functioning and body lipid change. This whole-farm model simulates a 365-day period for individual cows within a herd, with cow parameters randomly generated on the basis of the mean parameter values, defined as input and variance and co-variances from experimental data sets. The main inputs of e-Dairy are farm area, use of land, type of pasture, type of crops, monthly pasture growth rate, supplements offered, nutritional quality of feeds, herd description including herd size, age structure, calving pattern, BCS and LW at calving, probabilities of pregnancy, average genetic merit and economic values for items of income and costs. The model allows to set management policies to define: dry-off cows (ceasing of lactation), target pre- and post-grazing herbage mass and feed supplementation. The main outputs are herbage dry matter intake, annual pasture utilisation, milk yield, changes in BCS and LW, economic farm profit and return on assets. The model showed satisfactory accuracy of prediction when validated against two data sets from farmlet system experiments. Relative prediction errors were <10% for all variables, and concordance correlation coefficients over 0.80 for annual pasture utilisation, yields of milk and milk solids (MS; fat plus protein), and of 0.69 and 0.48 for LW and BCS, respectively. A simulation of two contrasting dairy systems is presented to show the practical use of the model. The model can be used to explore the effects of feeding level and genetic merit and their interactions for grazing dairy systems, evaluating the trade-offs between profit and the associated risk. PMID:23257214

Baudracco, J; Lopez-Villalobos, N; Holmes, C W; Comeron, E A; Macdonald, K A; Barry, T N

2013-05-01

3

Influence of different systems for feeding supplements to grazing dairy cows on milk fatty acid composition.  

PubMed

This study investigated the effects of different strategies for feeding supplements to grazing dairy cows on the proportions of fatty acids in milk. Two hundred and sixteen cows were fed supplementary grain and forage according to one of 3 different strategies; (1) Control: cows grazed perennial ryegrass pasture (14 kg dry matter/d) supplemented with milled barley grain fed in the milking parlour and pasture silage offered in the paddock; (2) Partial mixed ration 1 (PMR1): same pasture allotment and supplement as Control strategy, but the supplements presented as a mixed ration after each milking in feedpad, and; (3) Partial mixed ration 2 (PMR2): same pasture allotment, supplemented with a mixed ration of milled barley grain, alfalfa hay, corn silage and crushed corn grain fed in a feedpad. Within each strategy, cows were assigned to receive either 6, 8, 10 or 12 kg dry matter supplement/cow per d. Milk fatty acid proportions from cows fed Control and PMR1 strategies were similar and different from those fed PMR2, particularly at 10 to 12 kg dry matter supplement/cow per d. The reduction in milk fat yield and concentration in cows fed high amounts of supplement as Control and PMR1 was coincident with 4 × increase in 10t-18:1 proportion. The composition of the partial mixed ration (PMR) and the amount offered affected milk fatty acid proportions and milk fat content, however, the method of supplementation did not. PMID:24560061

Akbaridoust, Ghazal; Plozza, Tim; Trenerry, Victor C; Wales, William J; Auldist, Martin J; Dunshea, Frank R; Ajlouni, Said

2014-05-01

4

Extended grazing: a detailed analysis of Irish dairy farms.  

PubMed

Profitability and factors affecting grazing season length were econometrically analyzed using a representative sample of Irish dairy farms. The objective of this study was to explore what potential exists on Irish dairy farms to extend the grazing season and to quantify the possible economic benefits that result from lengthening the grazing season. Regression results indicate that location factors affect the length of the grazing season, but even when physical factors are controlled, farmer characteristics, such as education, also affect the grazing season length. The results of a panel data analysis show that significant cost reductions can be achieved by extending the grazing season. Overall, the findings indicate that lengthening the grazing season offers a cost-saving alternative on many Irish dairy farms, which could contribute to strengthening the competitiveness of the Irish dairy sector. PMID:22192197

Läpple, D; Hennessy, T; O'Donovan, M

2012-01-01

5

Metabolism of grazed vs. zero-grazed dairy cows throughout the vegetation period: hepatic and blood plasma parameters.  

PubMed

Grass may have a differential impact on the metabolism of the dairy cow, depending on the grazing system applied. In this study, the hypothesis was tested that metabolism of grazed vs. zero-grazed dairy cows is differently regulated throughout the vegetation period. The study included three experimental periods (p1, p2 and p3) of 14 days each, and two treatments [grazing from pasture, PASTURE, n = 9; or zero-grazing in a free-stall barn (BARN, n = 9)]. Blood and liver samples were collected at the end of each period when the cows were on average 64, 120 and 197 DIM. Concentrations of metabolites and hormones, and activities of various enzymes were determined in plasma. Liver samples were measured for mRNA abundance of genes encoding enzymes and nuclear receptors involved in metabolic pathways. PASTURE cows had higher plasma concentrations of T(3), BHB, and total protein than BARN cows across periods (p < 0.05). BARN cows had higher concentrations of NEFA (in p1) and urea (in p1 and p2) in relation PASTURE cows (p < 0.05), and had higher mRNA abundance of liver-X-receptor-? and glycerol-3-phosphate-acyltransferase across periods (p < 0.05). The results confirm the hypothesis that metabolism is different between BARN and PASTURE cows throughout the vegetation period, and show that the observed differences are mainly reflected in parameters of lipid metabolism. PMID:21453349

Kaufmann, L D; Dohme-Meier, F; Münger, A; Bruckmaier, R M; van Dorland, H A

2012-04-01

6

Changes in soil carbon cycling accompanying conversion of row-crop fields to grazing dairy pastures  

NASA Astrophysics Data System (ADS)

Increasingly, the dairy industry in the eastern US is transitioning from total confinement dairy systems (TCD) toward pasture-based, management intensive grazing dairy (MiGD) systems. This transition is driven by the fact that MiGDs require substantially less operating capital and are more economically efficient than TCD systems. Consequently, the impact of this transition and shift in land-use practice on carbon dynamics may be considerable. Land-use in a Management intensive Grazing Dairy (MiGD) system is fundamentally different than conventional confinement dairies and conventional no-till pastures. The forage system involves rotational grazing at optimal digestibility, when the plants are immature (~20-days) and consequently protein-rich. MiGD cows spend >90% of their time in the field and deposit > 90% of their waste directly to the soil surface. Thus, little above ground plant residues are directly returned to the soil, but rather substantial C inputs derive from bovine manure. We sampled a MiGD-chronosequence of row-crop to MiGD conversion established in 2007 in eastern Georgia. All soils across the MiGD-chronosequence, all occur in relative (40 km) close proximity to one another, are deep, well-drained, fine and fine sandy loam Ultisols formed on Coastal Plain sediments. Prior to MiGD established, the soils were farmed for > 50 yrs using conventional tillage techniques. Our current sampling to 1m depths captures fields at 0, 2, 3, and 5 yrs since conversion. Total soil carbon (C) and the carbon concentration of the clay fraction increased following conversion, with the greatest increases occurring between 3 and 5 yrs since conversion. These C increases were limited to the upper 40cm of the soil, with minimal change occurring at depth. Characterization of the protein and ligand content of these soils via 13C NMR and chemolytic techniques as a function of soil particle density and size is in progress and will be presented along with estimates of carbon dioxide and methane fluxes across the MiGD chronosequence. Our broad goal is to quantify ruminal methane emissions and changes to soil C-stocks and stability associated with this land-use shift. Our preliminary data suggest such a land-use change will likely improve soil health and increase C-stocks. Balancing this against potential increases in methane emissions is a key knowledge gap for future southeastern U.S. C-cycling estimates.

Thompson, A.; Kramer, M. G.; Hill, N.; Machmuller, M. B.; Cyle, K.

2011-12-01

7

Effect of pre-grazing herbage mass on dairy cow performance, grass dry matter production and output from perennial ryegrass (Lolium perenne L.) pastures.  

PubMed

A grazing study was undertaken to examine the effect of maintaining three levels of pre-grazing herbage mass (HM) on dairy cow performance, grass dry matter (DM) production and output from perennial ryegrass (Lolium perenne L.) pastures. Cows were randomly assigned to one of three pre-grazing HM treatments: 1150 - Low HM (L), 1400 - Medium HM (M) or 2000 kg DM/ha - High HM (H). Herbage accumulation under grazing was lowest (P<0.01) on the L treatment and cows grazing the L pastures required more grass silage supplementation during the grazing season (+73 kg DM/cow) to overcome pasture deficits due to lower pasture growth rates (P<0.05). Treatment did not affect daily milk production or pasture intake, although cows grazing the L pastures had to graze a greater daily area (P<0.01) and increase grazing time (P<0.05) to compensate for a lower pre-grazing HM (P<0.01). The results indicate that, while pre-grazing HM did not influence daily milk yield per cow, adapting the practise of grazing low HM (1150 kg DM/ha) pasture reduces pasture DM production and at a system level may increase the requirement for imported feed. PMID:24229787

Wims, C M; Delaby, L; Boland, T M; O'Donovan, M

2014-01-01

8

GRAZING SYSTEMS, ECOSYSTEM RESPONSES, AND GLOBAL CHANGE  

Microsoft Academic Search

Managed grazing covers more than 25% of the global land surface and has a larger geographic extent than any other form of land use. Grazing systems persist under marginal bioclimatic and edaphic conditions of different biomes, leading to the emergence of three regional syndromes inherent to global grazing: desertification, woody encroachment, and deforestation. These syndromes have widespread but differential effects

Gregory P. Asner; Andrew J. Elmore; Lydia P. Olander; Roberta E. Martin; A. Thomas Harris

2004-01-01

9

Phosphorus and Sediment Loss in a Catchment with Winter Forage Grazing of Cropland by Dairy Cattle  

Microsoft Academic Search

The loss of phosphorus and sediment to surface waters can impair their quality. It was hypothesized that the practice of winter grazing dairy cattle on cropland of moderate slope (5-20%) would exacerbate the loss of P and suspended sediment (SS) from land to water. In a small (4.3 ha) catchment two flumes were installed, upstream and downstream of one field

R. W. McDowell

2006-01-01

10

The effects on claw health of supplement feeding grazing dairy cows on feed pads.  

PubMed

The effects of feeding and management systems on the health and welfare of grazing dairy cows were investigated by comparing the claw health of cows fed grain during milking and pasture silage in the paddock (Control), with cows fed a grain-based partial mixed ration (PMR) on a concrete feed pad. Cows were assessed on three occasions during lactation: (1) early lactation (20-81 days in milk [DIM]) before allocation to feeding treatments; (2) mid-lactation (97-158 DIM) immediately following an intensive feeding experiment, and (3) late lactation (173-243 DIM) several months after return to initial management groups. At the final examination, claw puncture resistance was measured. The results showed that for the most prevalent lesions (white line disease, paintbrush haemorrhage and traumatic bruising), there was no effect of feeding system or amount of supplement on the presence of the moderate to severe forms in early lactation, but cows were more likely to have a particular lesion at the second assessment if it was present in early lactation. Puncture resistance of the claw was not related to presence of a lesion for any of the most prevalent lesion types. It was concluded for this herd that for most indicators of claw health, there was no overall effect of different feeding systems (supplement fed during milking or on a feed pad) or amount of supplement. PMID:24206633

Coombe, Joanne E; Pyman, Michael F; Mansell, Peter D; Auldist, Martin J; Anderson, Garry A; Wales, William J; Malmo, Jakob; Conley, Melanie J; Fisher, Andrew D

2013-12-01

11

Green leaf allowance and dairy ewe performance grazing on tropical pasture.  

PubMed

The objective of this study was to explain the influence of green leaf allowance levels on the performance of dairy ewes grazing a tropical grass. Seventy-two lactating ewes grazed Aruana guineagrass (Panicum maximum Jacq. cv. Aruana) for 80 d. The treatments were 4 daily levels of green leaf allowance (GLA) on a DM basis corresponding to 4, 7, 10, and 13 kg DM/100 kg BW, which were named low, medium-low, medium-high, and high level, respectively. The experimental design was completely randomized with 3 replications. During the experimental period, 4 grazing cycles were evaluated in a rotational stocking grazing method (4 d of grazing and 16 d of rest). There was a linear effect of GLA on forage mass, and increasing GLA resulted in increased total leaf mass, reaching an asymptotic plateau around the medium-high GLA level. The stem mass increased with increased GLA, and a pronounced increase was observed between medium-high and high GLAs. Increasing GLA increased both forage disappearance rate and postgrazing forage mass. Leaf proportion increased with GLA, peaking at the medium-high level, and the opposite occurred for stem proportions, which reduced until medium-high GLA level, followed by an increase on high GLA. Forage CP decreased linearly with GLA, and increasing GLA from low to high reduced CP content by 31%. On the other hand, NDF increased 14% and ADF increased 26%, both linearly in response to greater GLA levels. Total digestible nutrients decreased linearly by 8% when GLA increased from low to high level. Milk yield increased, peaking at medium-high GLA (1.75 kg ewe(-1) d(-1)) and decreased at high GLA level (1.40 kg ewe(-1) d(-1)). Milk composition was not affected by the GLA levels. There was a reduction in stocking rate from 72 to 43 ewes/ha when GLA increased from low to high level. Productivity (milk yield kg ha(-1) d(-1)) increased as GLA increased, peaking at medium-low level (115 kg ha(-1) d(-1)). Although this tropical grass showed the same pattern in responses to GLA levels as reported in the literature with temperate pastures, the magnitude of the process changed and the maximum response in milk yield from lactating dairy ewes grazing a tropical pasture would be achieved with higher forage allowances than in temperate pastures. Overall, Aruana guineagrass grazed by lactating dairy ewes should be managed to provide 7 to 10 GLA in kg DM/100 kg BW according to the production goals. PMID:24671589

De Souza, J; Batistel, F; Ticiani, E; Sandri, E C; Pedreira, C G S; Oliveira, D E

2014-06-01

12

Predicting grass dry matter intake, milk yield and milk fat and protein yield of spring calving grazing dairy cows during the grazing season.  

PubMed

Predicting the grass dry matter intake (GDMI), milk yield (MY) or milk fat and protein yield (milk solids yield (MSY)) of the grazing dairy herd is difficult. Decisions with regard to grazing management are based on guesstimates of the GDMI of the herd, yet GDMI is a critical factor influencing MY and MSY. A data set containing animal, sward, grazing management and concentrate supplementation variables recorded during weeks of GDMI measurement was used to develop multiple regression equations to predict GDMI, MY and MSY. The data set contained data from 245 grazing herds from 10 published studies conducted at Teagasc, Moorepark. A forward stepwise multiple regression technique was used to develop the multiple regression equations for each of the dependent variables (GDMI, MY, MSY) for three periods during the grazing season: spring (SP; 5 March to 30 April), summer (SU; 1 May to 31 July) and autumn (AU; 1 August to 31 October). The equations generated highlighted the importance of different variables associated with GDMI, MY and MSY during the grazing season. Peak MY was associated with an increase in GDMI, MY and MSY during the grazing season with the exception of GDMI in SU when BW accounted for more of the variation. A higher body condition score (BCS) at calving was associated with a lower GDMI in SP and SU and a lower MY and MSY in all periods. A higher BCS was associated with a higher GDMI in SP and SU, a higher MY in SU and AU and a higher MSY in all periods. The pre-grazing herbage mass of the sward (PGHM) above 4 cm was associated with a quadratic effect on GDMI in SP, on MY in SP and SU and on MSY in SU. An increase in daily herbage allowance (DHA) above 4 cm was associated with an increase in GDMI in AU, an increase in MY in SU and AU and MSY in AU. Supplementing grazing dairy cows with concentrate reduced GDMI and increased MY and MSY in all periods. The equations generated can be used by the Irish dairy industry during the grazing season to predict the GDMI, MY and MSY of grazing dairy herds. PMID:23570842

O'Neill, B F; Lewis, E; O'Donovan, M; Shalloo, L; Galvin, N; Mulligan, F J; Boland, T M; Delagarde, R

2013-08-01

13

Effects of supplementation and stage of lactation on performance of grazing dairy ewes.  

PubMed

The majority of dairy sheep in the world are fed pasture and supplemental grain during lactation; however, no trials have reported the effects of supplementation of dairy ewes grazing improved pastures in North America. In trial 1, 56 three-year-old grazing dairy ewes in early [21 +/- 10 d in milk (DIM)] or late (136 +/- 9 DIM) lactation were fed 0 or 0.82 kg of dry matter/d per ewe of supplement (16.5% crude protein mixture of corn and a soybean meal-based high-protein pellet) in a 2 x 2 factorial arrangement of treatments. There were no significant interactions between stage of lactation and supplementation treatments. Average test-day milk production was higher in early-lactation ewes than in late-lactation ewes (1.74 vs. 1.21 kg/d, respectively). Although test-day milk protein percentage was higher in late-lactation ewes than in early-lactation ewes (5.02 vs. 4.86%, respectively), there was no difference in milk fat percentage between stages of lactation. Supplemented ewes had higher milk production (1.59 vs. 1.36 kg/d, respectively), lower milk fat percentage (5.75 vs. 6.00%, respectively), and lower milk protein percentage (4.84 vs. 5.04%, respectively) than unsupplemented ewes. Milk urea N levels were similar between the 2 stages of lactation and between the 2 supplementation treatments and were above recommended levels for dairy sheep, indicating an excess intake or inefficient utilization of protein for both supplementation treatments. In trial 2, 96 two-, three-, and four-year-old grazing dairy ewes in midlactation (112 +/- 21 DIM) were randomly assigned to 4 treatments of 0, 0.41, 0.82, or 1.24 kg of dry matter/d per ewe of whole corn. Average test-day milk production increased linearly and milk fat percentage decreased quadratically with increasing amounts of corn supplementation. Milk protein yield increased linearly, and milk urea N levels decreased quadratically with increasing amounts of corn supplementation, suggesting an improvement in the utilization of pasture protein with increasing dietary energy intake. PMID:18349241

Mikolayunas, C M; Thomas, D L; Albrecht, K A; Combs, D K; Berger, Y M; Eckerman, S R

2008-04-01

14

Manipulating the Dietary Cation-Anion Difference via Drenching to Early-Lactation Dairy Cows Grazing Pasture  

Microsoft Academic Search

Diets offered to grazing dairy cows can vary consider- ably in their dietary cation-anion difference (DCAD) and are often well in excess of what has been considered optimal. The effects of a range of DCAD on the health and production of pasture-based dairy cows in early lactation was examined in a randomized block design. Fourgroupsof8cowswereofferedagenerousallowance of pasture (45 ± 6

J. R. Roche; S. Petch; J. K. Kay

2005-01-01

15

Effect of perennial ryegrass (Lolium perenne L.) cultivars on the milk yield of grazing dairy cows.  

PubMed

The objective of this experiment was to investigate the effect of four perennial ryegrass cultivars: Bealey, Astonenergy, Spelga and AberMagic on the milk yield and milk composition of grazing dairy cows. Two 4 × 4 latin square experiments were completed, one during the reproductive and the other during the vegetative growth phase of the cultivars. Thirty-two Holstein-Friesian dairy cows were divided into four groups, with each group assigned 17 days on each cultivar during both experiments. Within each observation period, milk yield and milk composition, sward morphology and pasture chemical composition were measured. During the reproductive growth phase, organic matter digestibility (OMD) was greater for Bealey and Astonenergy (P < 0.001; +1.6%). AberMagic contained a higher stem proportion (P < 0.01; +0.06) and a longer sheath height (P < 0.001; +1.9 cm). Consequently, cows grazing AberMagic recorded a lower milk yield (P < 0.001; -1.5 kg/day) and a lower milk solids yield (P < 0.001; -0.13 kg/day). During the vegetative growth phase, OMD was greater (P < 0.001; +1.1%) for Bealey, whereas the differences between the cultivars in terms of sward structure were smaller and did not appear to influence animal performance. As a result, cows grazing Bealey recorded a higher milk yield (P < 0.001; +0.9 kg/day) and a higher milk solids yield (P < 0.01; +0.08 kg/day). It was concluded that grass cultivar did influence milk yield due to variations in sward structure and chemical composition. PMID:23034142

Wims, C M; McEvoy, M; Delaby, L; Boland, T M; O'Donovan, M

2013-03-01

16

Effect of pregrazing herbage mass on methane production, dry matter intake, and milk production of grazing dairy cows during the mid-season period.  

PubMed

Increasing milk production from pasture while increasing grass dry matter intake (GDMI) and lowering methane (CH(4)) emissions are key objectives of low-cost dairy production systems. It was hypothesized that offering swards of low herbage mass with increased digestibility leads to increased milk output. A grazing experiment was undertaken to investigate the effects of varying levels of HM on CH(4) emissions, GDMI and milk production of grazing dairy cows during the mid-season grazing period (June to July). Prior to the experiment, 46 Holstein-Friesian dairy cows (46 d in milk) were randomly assigned to 1 of 2 treatments (n=23) in a randomized block design. The 2 treatments consisted of 2 target pregrazing HM: 1,000 kg of dry matter (DM)/ha (low herbage mass, LHM) or 2,200 kg of DM/ha (high herbage mass, HHM). The experimental period lasted 2 mo from June 1 until July 31. Within the experimental period, there were 2 measurement periods, measurement 1 (M1) and measurement 2 (M2), where CH(4) emissions, GDMI, and milk production were measured. Mean herbage mass throughout the measurement periods was 1,075 kg of DM/ha and 1,993 kg of DM/ha for the LHM and HHM treatments, respectively. Grass quality in terms of organic matter digestibility was significantly higher for the LHM treatment in M2 (+12 g/kg of DM). In M1, the effect of herbage mass on grass quality was approaching significance in favor of the LHM treatment. Herbage mass did not significantly affect milk production during the measurement periods. Cows grazing the LHM swards had increased GDMI in M1 (+1.5 kg of DM) compared with cows grazing the HHM swards; no difference in GDMI was observed in M2. Grazing HHM swards increased CH(4) production per cow per day (+42 g), per kilogram of milk yield (+3.5 g/kg of milk), per kilogram of milk solids (+47 g/kg of milk solids), and per kilogram of GDMI (+3.1 g/kg of GDMI) in M2. Cows grazing the HHM swards lost a greater proportion of their gross energy intake as CH(4) during both measurement periods (+0.9% and +1% for M1 and M2, respectively). It was concluded that grazing LHM swards would increase grass quality with a concurrent reduction in CH(4) emissions. PMID:20855032

Wims, C M; Deighton, M H; Lewis, E; O'Loughlin, B; Delaby, L; Boland, T M; O'Donovan, M

2010-10-01

17

Comparison of three methods for gastrointestinal nematode diagnosis determination in grazing dairy cattle in relation to milk production  

Microsoft Academic Search

Development of resistance to anthelmintic drugs has motivated the search for diagnostic methods to identify animals for targeted selective treatments. We compared three methods for the diagnosis of nematode infection in relation to milk production in a fully grazing dairy herd of 150 cows in the humid Pampa (Argentina). Animals had feces, blood and milk sampled during the first postpartum

M. E. Mejía; A. F. Perri; N. Licoff; M. M. Miglierina; S. Cseh; A. M. Ornstein; D. Becu-Villalobos; I. M. Lacau-Mengido

18

Effect of protein supplementation on milk production and metabolism of dairy cows grazing tropical grass.  

PubMed

The objectives of this study were to determine if midlactation dairy cows (Bos taurus L.) grazing intensively managed elephantgrass would have their protein requirement met exclusively with the pasture and an energy concentrate, making the use of protein ingredients unnecessary, as well as to determine the dietary crude protein (CP) content that would optimize the efficiency of N utilization (ENU). Thirty-three Holstein and crossbred (Holstein × Jersey) midlactation dairy cows, producing approximately 20 kg/d, were grouped within breed into 11 blocks according to milk yield and days in milk. Within blocks, cows were randomly assigned to 1 of 3 treatments and remained in the study for 11 wk. The control treatment contained only finely ground corn, minerals, and vitamins, and it was formulated to be 8.7% CP. Two higher levels of CP (formulated to be 13.4 and 18.1%) were achieved by replacing corn with solvent-extracted soybean meal (SSBM). Pasture was fertilized with 50 kg of N/ha after each grazing cycle and averaged 18.5% CP (dry matter basis). No differences were observed in milk yield or milk fat, protein, and casein content or casein yield. In addition, pasture intake was not different among treatments. Milk urea N increased linearly as the concentrate CP content increased. Cows fed the 8.7% CP concentrate had higher ENU. In another experiment, 4 ruminally cannulated Holstein dry cows were used in a metabolism trial designed in a 4×4 Latin square. Cows were fed the same treatments described as well as a fourth treatment with 13.4% CP in the concentrate, in which urea replaced SSBM as the main N source. Ruminal volatile fatty acid concentration and microbial synthesis were not affected by levels or sources of N in the concentrate. Ruminal NH(3)N content increased as the concentrate CP content increased. Inclusion of SSBM in the concentrate did not increase production and decreased the ENU of midlactation dairy cows grazing on tropical forage. Supplementation of an 8.7% CP concentrate, resulting in a diet with CP levels between 15.3 and 15.7% of dry matter, was sufficient to meet the protein requirements of such milk production, with the highest ENU (18.4%). PMID:23127909

Danes, M A C; Chagas, L J; Pedroso, A M; Santos, F A P

2013-01-01

19

Comparison of three methods for gastrointestinal nematode diagnosis determination in grazing dairy cattle in relation to milk production.  

PubMed

Development of resistance to anthelmintic drugs has motivated the search for diagnostic methods to identify animals for targeted selective treatments. We compared three methods for the diagnosis of nematode infection in relation to milk production in a fully grazing dairy herd of 150 cows in the humid Pampa (Argentina). Animals had feces, blood and milk sampled during the first postpartum month for EPG, pepsinogen and anti-Ostertagia antibody determination, respectively. With the results obtained two groups of cows, divided in high and low parasite burden, were conformed for each method, and milk production was then compared between groups. When cows were separated by the EPG method (EPG=0 (N=106) vs. EPG>0 (N=44)) a difference of nearly 800 l of milk per cow per lactation was found (P<0.05). On the other hand, milk production between groups separated by Pepsinogen (mUtyr ? 1000 vs. mUtyr > 1000) or by anti-Ostertagia (ODR ? 0.5 vs. ODR > 0.5) results did not differ. Interestingly, proportion of cows in each group differed between methods (P<0.0001), and the anti-Ostertagia method yielded significantly more cows in the high index group compared to results using the EPG or Pepsinogen method. No correlations were found between parasite indexes determined by the different methods. High parasite burden estimation found may be ascribed to the production system, fully grazing all year round, and to the sampling time, at the beginning of lactation with cows in negative energy balance and depressed immunity. The fact that the cows were born and reared outside, on pasture with continuous nematode larvae exposure, may also account for the results obtained. In conclusion, EPG counting during the first postpartum month may be a useful tool for the diagnosis of production impairment induced by high nematode burden in adult grazing dairy cows. The anthelmintic treatment of only the EPG-positive recently calved cows would improve milk production, while reducing selective pressure on nematode population for the development of resistance. PMID:21798669

Mejía, M E; Perri, A F; Licoff, N; Miglierina, M M; Cseh, S; Ornstein, A M; Becu-Villalobos, D; Lacau-Mengido, I M

2011-12-29

20

Systems In Organic Dairy Production  

Microsoft Academic Search

The aim of this study was to explore stakeholder perceptions of the contribution of an Automatic Milking System (AMS) to sustainable\\u000a development of organic dairy production in Denmark and the Netherlands. In addition, reasons for the current difference in\\u000a AMS use on organic dairy farms between both countries were explored. To answer above mentioned aims, farmers and advisors\\u000a in both

Frank W. Oudshoorn; Reint Jan Renes; Imke J. M. De Boer

2008-01-01

21

Supplemental dietary protein for grazing dairy cows: effect on pasture intake and lactation performance.  

PubMed

One hundred twenty-four cows (92 multiparous and 32 primiparous) were used to evaluate the effect of grain supplements containing high crude protein [(22.8% CP, 5.3% rumen undegradable protein (RUP), dry matter basis], moderate CP (16.6% CP, 6.1% RUP), and moderate CP with supplemental RUP (16.2% CP, 10.8% RUP) on lactation performance of Holstein cows rotationally grazing annual ryegrass-oat pastures. Supplemental protein was provided by solvent extracted soybean meal in the high CP and moderate CP supplements and as a corn gluten meal-blood meal mixture (2.8:1) in the moderate CP, high RUP supplement. Cows were blocked according to previous mature milk equivalent production and calving date (partum group; 0 d in milk or postpartum group; 21 to 65 d in milk) and randomly assigned to dietary treatments. Grain was individually fed, at approximately a 1:3 grain to milk ratio, before a.m. and p.m milkings. The study was replicated during two grazing seasons that averaged 199 d. Cows had ad libitum access to bermudagrass hay while on pasture (dry matter intake = 1.3 kg/d). Protein supplementation had no effect on study long pasture dry matter (12.7 +/- 1.0 kg/d) or total dry matter (23.9 +/- 1.2 kg/d) consumption. Protein concentration did not affect actual milk yield of either calving group (high CP vs. moderate CP); however, postpartum group cows receiving high CP grain supplements maintained greater milk fat concentrations (3.34 vs. 3.11%), which led to higher fat-corrected milk (FCM) yields than control cows receiving moderate CP grain diets (30.3 vs. 28.9 kg/d). Crude protein concentration in milk of high CP-supplemented, postpartum group cows was also higher than moderate CP cows (3.42 vs. 3.27%). Additional RUP did not increase FCM yield above that generated by moderate CP grain diets for partum (34.3 vs. 32.9 kg/d) or postpartum-group cows (28.9 vs. 28.2 kg/d). Increasing CP concentration of grain supplement did not affect milk yield of Holstein cows grazing immature winter annual pastures. Supplementing additional RUP was without benefit, indicating that in this study energy deprivation may have been the major nutritional constraint for high-producing dairy cows grazing lush pastures. PMID:11352166

McCormick, M E; Ward, J D; Redfearn, D D; French, D D; Blouin, D C; Chapa, A M; Fernandez, J M

2001-04-01

22

Simulating the impact of global warming on milk and forage production in Scotland: 2. The effects on milk yields and grazing management of dairy herds  

Microsoft Academic Search

The potential impact of global warming and the enhanced atmospheric CO2 concentration on grassland management on dairy farms within the UK requires assessment. This has led to the development of a mathematical model of the grazing dairy cow. The model, that embraces grass and grass-white clover swards, has been used to assess the effects that the projected increases in temperature

Cairistiona F. E. Topp; Christopher J. Doyle

1996-01-01

23

Effect of feeding non-fibrous carbohydrate before grazing on intake and nitrogen utilization in dairy cows throughout the grazing season.  

PubMed

Ten lactating cows were used to determine the effect of feeding non-fibrous carbohydrate (NFC) supplement before grazing on feed intake and nitrogen (N) utilization throughout a grazing season. The experiment was conducted from June to September. Cows grazed twice a day (2.5 h × 2) under a set stocking system and were fed NFC supplement (1 kg/4 kg of milk yield) 2 h before grazing (PRE) or immediately after grazing (POST). Cows were also fed a grass and corn silage mixture ad libitum. Herbage dry matter intake (DMI) was greater for PRE than for POST throughout the experiment and decreased from June to September. Conversely, silage DMI was less for PRE than for POST throughout the experiment and increased over the grazing season. Consequently, total DMI for PRE did not differ from that for POST. Milk urea-N concentration and urinary urea-N excretion in June did not differ between the treatments, whereas that after July was higher for PRE than for POST. Proportion of urinary N excretion to absorbed N intake in June was lower for PRE than for POST, but that after July was higher for PRE than for POST. Feeding NFC supplement before grazing would improve N utilization when cows eat large amounts of herbage high in N. PMID:22339692

Mitani, Tomohiro; Ueda, Koichiro; Endo, Tetsushiro; Takahashi, Makoto; Nakatsuji, Hiroki; Kondo, Seiji

2012-02-01

24

Partial replacement of corn grain by hydrogenated oil in grazing dairy cows in early lactation.  

PubMed

Thirty-six grazing dairy cows were used to determine milk production and composition, and dry matter and energy intake when corn grain was partially replaced by hydrogenated oil in the concentrate. Four additional cows, each fitted with a ruminal cannula, were used in a crossover design to evaluate effects of supplemental fat on rumen environment and pasture digestion. All cows grazed mixed pastures with an herbage allowance of 30 kg dry matter/cow per day. The control group was fed a concentrate containing corn grain (4.49 kg dry matter/cow per day) and fishmeal (0.37 kg dry matter/cow per day), whereas the other group (fat) received a concentrate containing corn grain (2.87 kg dry matter/cow per day), fishmeal (0.37 kg dry matter/cow per day) and fat (0.7 kg dry matter/cow per day). The fat was obtained by hydrogenation of vegetable oils (melting point 58 to 60 degrees C, 30.3% C16:0, 34.9% C18:0, 21.8% C18:1, 3.3% C18:2). Supplemental fat increased milk production (control = 23.7 vs. fat = 25.0 kg/cow per day), fat-corrected milk (control = 22.5 vs. fat = 24.5 kg/cow per day), milk fat content (control = 3.64% vs. fat = 3.86%) and yields of milk fat (control = 0.86 vs. fat = 0.97 kg/cow per day) and protein (control = 0.74 vs. fat = 0.78 kg/cow per day). Milk percentages of protein, lactose, casein, cholesterol, and urea nitrogen were not affected. Pasture DMI and total DMI of pasture and concentrate and estimated energy intake were unchanged. No differences in loss of body weight or body condition score were detected. Plasma concentrations of nonesterified fatty acids, somatotropin, insulin, and insulin-like growth factor were not affected by supplemental fat. Concentrations of plasma triglyceride and total cholesterol were increased by supplemented fat, and no changes in plasma glucose and urea nitrogen were observed. The acetate-to-propionate ratio was higher in rumen fluid of cows that consumed fat (fat = 3.39 vs. control = 3.27). In situ pasture NDF degradation was not affected. The partial replacement of corn grain with fat improved the productive performance of early-lactation cows grazing spring pastures. No negative effects of supplemental fat on ruminal fiber digestion were detected. PMID:15290975

Salado, E E; Gagliostro, G A; Becu-Villalobos, D; Lacau-Mengido, I

2004-05-01

25

Mixed Grazing Systems Benefit both Upland Biodiversity and Livestock Production  

PubMed Central

Background With world food demand expected to double by 2050, identifying farming systems that benefit both agricultural production and biodiversity is a fundamentally important challenge for the 21st century, but this has to be achieved in a sustainable way. Livestock grazing management directly influences both economic outputs and biodiversity on upland farms while contributing to potentially damaging greenhouse gas emissions, yet no study has attempted to address these impacts simultaneously. Methods Using a replicated, landscape-scale field experiment consisting of five management ‘systems’ we tested the effects of progressively altering elements within an upland farming system, viz i) incorporating cattle grazing into an upland sheep system, ii) integrating grazing of semi-natural rough grazing into a mixed grazing system based on improved pasture, iii) altering the stocking ratio within a mixed grazing system, and iv) replacing modern crossbred cattle with a traditional breed. We quantified the impacts on livestock productivity and numbers of birds and butterflies over four years. Results, Conclusion and Significance We found that management systems incorporating mixed grazing with cattle improve livestock productivity and reduce methane emissions relative to sheep only systems. Systems that also included semi-natural rough grazing consistently supported more species of birds and butterflies, and it was possible to incorporate bouts of summer grazing of these pastures by cattle to meet habitat management prescriptions without compromising cattle performance overall. We found no evidence that the system incorporating a cattle breed popular as a conservation grazer was any better for bird and butterfly species richness than those based on a mainstream breed, yet methane emissions from such a system were predicted to be higher. We have demonstrated that mixed upland grazing systems not only improve livestock production, but also benefit biodiversity, suggesting a ‘win-win’ solution for farmers and conservationists.

Fraser, Mariecia D.; Moorby, Jon M.; Vale, James E.; Evans, Darren M.

2014-01-01

26

Diet Supplementation with Fish Oil and Sunflower Oil to Increase Conjugated Linoleic Acid Levels in Milk Fat of Partially Grazing Dairy Cows  

Microsoft Academic Search

The objective of this study was to determine the long- termeffect onmilk conjugatedlinoleic acid(cis-9,trans- 11 CLA) of adding fish oil (FO) and sunflower oil (SFO) to the diets of partially grazing dairy cows. Fourteen Holstein cows were divided into 2 groups (7 cows\\/treat- ment) and fed either a control or oil-supplemented diet for 8 wk while partially grazing pasture. Cows

A. A. AbuGhazaleh; L. D. Holmes

2007-01-01

27

Continuous and Long-Term Measurement of Reticuloruminal pH in Grazing Dairy Cows by an Indwelling and Wireless Data Transmitting Unit  

PubMed Central

The aim of the present study was the continuous measurement of ruminal pH in grazing dairy cows to monitor the diets effects on ruminal pH value. A novel indwelling pH-measurement and data transmitting system was given to 6 multiparous cows orally. Ruminal pH was measured every 600?sec over a 40?d period. After barn feeding and changeover to pasture, the following 3 treatments (2 cows/treatment) were included in the measurement period: continuous grazing (G), continuous grazing plus 4?kg/d of hay fed twice daily (GH), and continuous grazing plus 4?kg/d of concentrate (GC). Ruminal pH decreased significantly (P < 0.05) from 6.58 ± 0.15 to pH 6.19 ± 0.19 during feed changeover to pasture. Mean ruminal pH for G, GH, and GC was 6.36, 6.56, and 6.01. Mean 24-h minimum pH was 5.95, 6.20 and, 5.58. The time pH was below 6.3, 6.0, 5.8, and 5.5, for G it was 583, 91, 26, and 3?min/d, for GH it was 97, 12, 0, and 0?min/d and for GC it was 1126, 621, 347, and 101?min/d, respectively. Results were significantly influenced by the diet. The indwelling pH-measurement and data transmitting system is a very useful and proper tool for long-term measurement of ruminal pH in cows.

Gasteiner, J.; Guggenberger, T.; Hausler, J.; Steinwidder, A.

2012-01-01

28

Dugong grazing and turtle cropping: grazing optimization in tropical seagrass systems?  

PubMed

Grazing by dugongs and cropping by green turtles have the capacity to alter the subsequent nutritional quality of seagrass regrowth. We examined the effects of simulated light and intensive grazing by dugongs and cropping by turtles on eight nutritionally relevant measures of seagrass chemical composition over two regrowth periods (short-term, 1-4 months; long-term, 11-13 months) at two seagrass communities (a mixed species community with Zostera capricorni, Halophila ovalis, Halodule uninervis, Cymodocea rotundata and C. serrulate; and a monospecific bed of Halodule uninervis) in tropical Queensland, Australia. The concentrations of organic matter, total nitrogen, total water-soluble carbohydrates, total starch, neutral detergent fiber, acid detergent fiber, acid lignin, as well as the in vitro dry matter digestibility (IVDMD) were measured in the leaves and below-ground parts of each species using near-infrared reflectance spectroscopy (NIRS). Regrowth of preferred species such as H. ovalis and H. uninervis from simulated intensive dugong grazing after a year exhibited increased (by 35 and 25%, respectively, relative to controls) whole-plant N concentrations. Similarly, regrowth of H. ovalis from simulated turtle cropping showed an increase in the leaf N concentration of 30% after a year. However, these gains are tempered by reductions in starch concentrations and increases in fiber. In the short-term, the N concentrations increased while the fiber concentrations decreased. These data provide experimental support for a grazing optimization view of herbivory in the tropical seagrass system, but with feedback in a different manner. Furthermore, we suggest that in areas where grazing is the only major source of natural disturbance, it is likely that there are potential ecosystem level effects if and when numbers of dugongs and turtles are reduced. PMID:16821013

Aragones, Lemnuel V; Lawler, Ivan R; Foley, William J; Marsh, Helene

2006-10-01

29

Dairy inbreeding intelligent decision terminal system based on mobile  

Microsoft Academic Search

A dairy inbreeding intelligent decision terminal system based on PDA is proposed to carry out dairy breeding, firstly, the dairy inbreeding coefficient is estimated according to the Latus Rectum Theory, Then the best bull with the smallest inbreeding coefficient and descendants of the genetic traits is predicted to realize high-quality dairy breeding, This system use RDA technology to realize the

Wei Xiao-Li; Zhang Yong-gen; Wu Ya-chu

2010-01-01

30

The energy expenditure of 2 Holstein cow strains in an organic grazing system.  

PubMed

Until recently, measurements of energy expenditure (EE; herein defined as heat production) in respiration chambers did not account for the extra energy requirements of grazing dairy cows on pasture. As energy is first limiting in most pasture-based milk production systems, its efficient use is important. Therefore, the aim of the present study was to compare EE, which can be affected by differences in body weight (BW), body composition, grazing behavior, physical activity, and milk production level, in 2 Holstein cow strains. Twelve Swiss Holstein-Friesian (HCH; 616kg of BW) and 12 New Zealand Holstein-Friesian (HNZ; 570kg of BW) cows in the third stage of lactation were paired according to their stage of lactation and kept in a rotational, full-time grazing system without concentrate supplementation. After adaption, the daily milk yield, grass intake using the alkane double-indicator technique, nutrient digestibility, physical activity, and grazing behavior recorded by an automatic jaw movement recorder were investigated over 7d. Using the (13)C bicarbonate dilution technique in combination with an automatic blood sampling system, EE based on measured carbon dioxide production was determined in 1 cow pair per day between 0800 to 1400h. The HCH were heavier and had a lower body condition score compared with HNZ, but the difference in BW was smaller compared with former studies. Milk production, grass intake, and nutrient digestibility did not differ between the 2 cow strains, but HCH grazed for a longer time during the 6-h measurement period and performed more grazing mastication compared with the HNZ. No difference was found between the 2 cow strains with regard to EE (291±15.6kJ) per kilogram of metabolic BW, mainly due to a high between-animal variation in EE. As efficiency and energy use are important in sustainable, pasture-based, organic milk production systems, the determining factors for EE, such as methodology, genetics, physical activity, grazing behavior, and pasture quality, should be investigated and quantified in more detail in future studies. PMID:24630659

Thanner, S; Dohme-Meier, F; Görs, S; Metges, C C; Bruckmaier, R M; Schori, F

2014-05-01

31

Differences in sward structure of ryegrass cultivars and impact on milk production of grazing dairy cows  

Microsoft Academic Search

Animal trials cannot be used in routine in a forage grass-breeding programme or in a cultivar testing procedure. An alternative to these animal trials is to identify plant traits associated with a high animal production under grazing that could be used as selection criteria. For this, the effect of sward structure on milk production was studied, comparing four late-heading diploid

Manuel FLORES-LESAMAa; Laurent Hazard; Michèle Betin; Jean-Claude Emile

2006-01-01

32

Phosphorus Fertilizer and Grazing Management Eff ects on Phosphorus in Runoff from Dairy Pastures  

Microsoft Academic Search

ects on runoff P concentration of P rate, P rate × number of applications (P < 0.001), P rate × time since fertilizer ( P < 0.001), dung P (P < 0.001), time since grazing ( P < 0.05), and pasture biomass (P < 0.001). A conceptual model of the sources of P in runoff comprising three components is proposed

Warwick J. Dougherty; Paul J. Nicholls; Paul J. Milham; J. Havilah; Roy A. Lawrie

33

Milk Response to Concentrate Supplementation of High Producing Dairy Cows Grazing at Two Pasture Allowances  

Microsoft Academic Search

Twenty multiparous Holstein cows (four ruminally cannulated)infive4 ×4Latinsquareswith21-dperiods were used to study the effect of concentrate supplemen- tation when grazed at two pasture allowances. The four dietary treatments resulted from the combination of two pasture allowance targets (low, 25 vs. high, 40 kg of dry matter\\/cow per day) and two concentrate supple- mentation levels (zero vs. 1 kg of concentrate\\/4

F. Bargo; L. D. Muller; J. E. Delahoy; T. W. Cassidy

2002-01-01

34

Analysis of FEL optical systems with grazing incidence mirrors  

SciTech Connect

The use of grazing incidence optics in resonators alleviates the problem of damage to the optical elements and permits higher powers in cavities of reasonable dimensions for a free electron laser (FEL). The design and manufacture of a grazing incidence beam expander for the Los Alamos FEL mock-up has been completed. In this paper, we describe the analysis of a bare cavity, grazing incidence optical beam expander for an FEL system. Since the existing geometrical and physical optics codes were inadequate for such an analysis, the GLAD code was modified to include global coordinates, exact conic representation, raytracing, and exact aberration features to determine the alignment sensitivities of laser resonators. A resonator cavity has been manufactured and experimentally setup in the Optical Evaluation Laboratory at Los Alamos. Calculated performance is compared with the laboratory measurements obtained so far.

Knapp, C.E.; Viswanathan, V.K.; Bender, S.C.; Appert, Q.D.; Lawrence, G.; Barnard, C.

1986-01-01

35

Rumen biohydrogenation-derived fatty acids in milk fat from grazing dairy cows supplemented with rapeseed, sunflower, or linseed oils.  

PubMed

The effects of supplementation with rapeseed, sunflower, and linseed oils (0.5 kg/d; good sources of oleic, linoleic, and linolenic acids, respectively) on milk responses and milk fat fatty acid (FA) profile, with special emphasis on rumen-derived biohydrogenation intermediates (BI), were evaluated in a replicated 4 x 4 Latin square study using 16 grazing dairy cows. The dietary treatments were 1) control diet: 20-h access to grazing pasture supplemented with 5 kg/d of corn-based concentrate mixture (96% corn; CC); 2) RO diet: 20-h access to grazing supplemented with 4.5 kg/d of CC and 0.5 kg of rapeseed oil; 3) SO diet: 20-h access to grazing supplemented with 4.5 kg/d of CC and 0.5 kg of sunflower oil; and 4) LO diet: 20-h access to grazing supplemented with 4.5 kg/d of CC and 0.5 kg of linseed oil. Milk fatty acids were converted to methyl esters and analyzed by gas-liquid chromatography and silver-ion HPLC. Dietary treatments had no effect on milk production or on milk protein content and milk protein production. Supplementation with rapeseed and sunflower oils lowered milk fat content and milk fat production, but linseed oil had no effect. Inclusion of dietary vegetable oils promoted lower concentrations of short-chain (including 4:0) and medium-chain FA (including odd- and branched-chain FA) and 18:3n-3, and higher concentrations of C(18) FA (including stearic and oleic acids). The BI concentration was higher with the dietary inclusion of vegetable oils, although the magnitude of the concentration and its pattern differed between oils. The RO treatment resulted in moderate increases in BI, including trans 18:1 isomers and 18:2 trans-7,cis-9, but failed to increase 18:1 trans-11 and 18:2 cis-9,trans-11. Sunflower oil supplementation resulted in the highest concentrations of the 18:1 trans-10, 18:1 cis-12, and 18:2 trans-10,trans-12 isomers. Concentrations of 18:1 trans-11 and 18:2 cis-9,trans-11 were higher than with the control and RO treatments but were similar to the LO treatment. Concentration of BI in milk fat was maximal with LO, having the highest concentrations of some 18:1 isomers (i.e., trans-13/14, trans-15, cis-15, cis-16), most of the nonconjugated 18:2 isomers (i.e., trans-11,trans-15, trans-11,cis-15, cis-9,cis-15, and cis-12,cis-15), and conjugated 18:2 isomers (i.e., trans-11,cis-13, cis-12,trans-14, trans-11,trans-13, trans-12,trans-14, and trans-9,trans-11), and all conjugated 18:3 isomers. The LO treatment induced the highest amount and diversity of BI without decreasing milk fat concentration, as the RO and SO treatments had, suggesting that the BI associated with 18:3n-3 intake may not be the major contributors to inhibition of mammary milk fat synthesis. PMID:19700715

Rego, O A; Alves, S P; Antunes, L M S; Rosa, H J D; Alfaia, C F M; Prates, J A M; Cabrita, A R J; Fonseca, A J M; Bessa, R J B

2009-09-01

36

Dairy goat production systems: status quo, perspectives and challenges.  

PubMed

Goat production concentrated in developing countries (tropics, dry areas), contributes largely to the livelihoods of low and medium income farmers. Farming systems in these areas have evolved to cope with the formidable constraints imposed by harsh natural and economic conditions by adapting integrated crop/livestock production strategies. In Asia, Africa and Latin America, due to its almost exclusive extensive nature, goat production relies mainly on grazing on communal lands that hardly provide the minimum nutrient requirements due to overstocking and degradation. While some of these production systems are becoming semi-intensive, appropriate breeding strategies should be designed to promote conservation and improvement of their unique attributes, such as adaptability, water use efficiency and suitability under harsh climatic conditions. In Europe, dairy goat production is more common around the Mediterranean basin, where it is important from an economic, environmental and sociological perspective to the Mediterranean countries: Spain, France, Italy and Greece. Europe owns only 5.1 % of the world's dairy goat herds, but produces 15.6 % of the world's goat milk; this is the only continent where goat milk has such an economic importance and organization. In developing countries the dairy goat sector requires a systemic approach, whereby nutrition, animal health, breeding, know-how, inputs and technologies must be assembled. This would allow the optimization of natural and local resources and would promote the transition from a risk reduction strategy towards an increased productivity strategy. Such an increase would privilege production efficiency based on clean, green and ethical practices for responsible innovation. PMID:22890482

Escareño, Luis; Salinas-Gonzalez, Homero; Wurzinger, Maria; Iñiguez, Luiz; Sölkner, Johann; Meza-Herrera, Cesar

2012-12-01

37

Evaluation of the effect of eprinomectin in young dairy heifers sub-clinically infected with gastrointestinal nematodes on grazing behaviour and diet selection.  

PubMed

Inappetence is commonly associated with parasitism and has been observed in both housed and pastured ruminants. In seeking a functional explanation for these observations, it has been hypothesised that parasitized animals may feed more selectively in order to proportionally increase the protein content of their diet and thus partially compensate for their reduced feed intake. Support for this theory is found principally in studies in housed animals under carefully controlled experimental conditions. Grazing animals face a far more heterogeneous environment and a multiplicity of potentially confounding factors that could influence diet selection. Controlled grazing of adjacent monocultures of grass and clover can mitigate some of these variables and was used in the current study to examine the dietary preference of dairy heifers with sub-clinical parasitic gastroenteritis when compared to those receiving regular anthelmintic treatments. Grazing behaviour and herbage intake rates were determined through the use of jaw-movement recorders, direct observation and short-term liveweight change. Consistent with previous observations and despite evidence that nematode burdens were low in the untreated control heifers, a reduction in daily grazing time of 56min (P=0.054) was observed in the control animals. There was, however, no evidence that the control heifers showed greater preference for clover compared with ryegrass: partial preference for clover was 73.0% in the untreated controls and 75.5% in the treated heifers. Furthermore control heifers were observed grazing the clover swards significantly (P=0.032) less frequently than the treated heifers. This study provides additional evidence in grazing cattle for parasite-induced inappetence, manifest as a reduction in grazing time and in subtle changes in ingestive behaviour. The observed partial preference for clover in both treated and control cattle was not significantly affected by the level of parasitism. PMID:18006234

Forbes, A B; Huckle, C A; Gibb, M J

2007-12-25

38

Gastrointestinal parasites presence during the peripartum decreases total milk production in grazing dairy Holstein cows.  

PubMed

Parasitism in cattle is known to impair growth and development. Recent findings suggest that productivity of adult animals is also affected, but little is known about the physiological mechanisms involved. Furthermore, development of nematode resistance to drugs makes imperative the search of management practices that avoid whole herd treatment. We undertook an epidemiological and endocrine study in a grass based dairy farm in Argentina to study the effect of parasites on milk production and the underlying mechanisms involved, and identify individual animals that would benefit from antiparasitic treatment. All the cows in the dairy were followed monthly for egg parasite output in feces. Samples were cultured for genera determination. Milk production and reproductive results were recorded and periodical bleedings for hormone determination were performed. Nematode egg output (EPG) was maximal in late Summer and Autumn and minimal in Spring in coincidence with the Ostertagia inhibition-disinhibition cycle as this genus had the highest prevalence in all the study. The highest proportion of positive samples was found in the high producing herd and maximal counts were found in the peripartal period. Milk production did not correlate with EPG mean values but, when cows were grouped by EPG positivity around parturition, a significant difference in total milk production between EPG null and positive cows was observed. Positive cows produced 7%, 12% or 15% less milk than null EPG cows, depending on the sampling month/s chosen for classification. The highest difference was seen when both prepartum and postpartum samples were taken into account. No difference in lactation length and a marginal effect on partum to first service interval were encountered. Endocrine studies revealed a decrease in serum growth hormone (GH), type I insulin-like growth factor (IGF-I) and prolactin during lactation in cows with positive EPG in the first postpartum sample with respect to null EPG cows at that time. GH levels decreased and prolactin and IGF-I levels increased in both groups of cows from month 0 to 6 in milk. Serum insulin levels remained stable throughout lactation and were similar in both groups of cows. In conclusion, EPG around parturition may be a useful tool for identifying cows that will have a decrease in productivity due to parasite effects and would possibly benefit from an antiparasitic treatment. Besides, our results suggest that detrimental effect of parasites on milk production may be mediated by GH, IGF-I and prolactin serum levels. PMID:21269774

Perri, A F; Mejía, M E; Licoff, N; Lazaro, L; Miglierina, M; Ornstein, A; Becu-Villalobos, D; Lacau-Mengido, I M

2011-06-10

39

Manipulating the dietary cation-anion difference via drenching to early-lactation dairy cows grazing pasture.  

PubMed

Diets offered to grazing dairy cows can vary considerably in their dietary cation-anion difference (DCAD) and are often well in excess of what has been considered optimal. The effects of a range of DCAD on the health and production of pasture-based dairy cows in early lactation was examined in a randomized block design. Four groups of 8 cows were offered a generous allowance of pasture (45 +/- 6 kg/d of dry matter (DM) per cow) for 35 d and achieved mean pasture intakes of approximately 17 kg/d of DM per cow. Cows were drenched twice daily with varying combinations of mineral compounds to alter the DCAD. Dietary cation-anion difference ranged from +23 to +88 mEq/100 g of DM. A linear increase in blood pH and HCO(3)(-) concentration and blood base excess, and a curvilinear increase in the pH of urine with increasing DCAD indicated a nonrespiratory effect of DCAD on metabolic acid-base balance. Plasma concentrations of Mg, K, and Cl declined as DCAD increased, whereas Na concentration increased. Urinary excretion of Ca decreased linearly as DCAD increased, although the data suggest that the decline may be curvilinear. These results in conjunction with the increased concentrations of ionized Ca suggest that intestinal absorption of Ca or bone resorption, or both, increased as DCAD declined. Dry matter intake, as measured using indigestible markers, was not significantly affected by DCAD. However, the linear increase in the yield of linolenic acid, vaccenic acid, and cis-9, trans-11 conjugated linoleic acid in milk, as DCAD increased is consistent with a positive effect of DCAD on DM intake. Increasing DCAD did not significantly affect milk yield or milk protein, but the concentration and yield of milk fat linearly increased with increasing DCAD. The increased milk fat yield was predominantly a result of increased de novo synthesis in the mammary epithelial cells, although an increase in the yield of preformed fatty acids also occurred. Milk production results suggest that DCAD for optimal production on pasture diets may be higher than the +20 mEq/100 g of DM previously identified for total mixed rations. PMID:15591389

Roche, J R; Petch, S; Kay, J K

2005-01-01

40

Trace Element Supplementation of Livestock in New Zealand: Meeting the Challenges of Free-Range Grazing Systems  

PubMed Central

Managing the mineral nutrition of free-range grazing livestock can be challenging. On farms where grazing animals are infrequently yarded, there are limited opportunities to administer trace element supplements via feeds and concentrates. In New Zealand, where the majority of sheep, cattle, and deer graze pasture year round, inadequate intake of cobalt, copper, iodine and selenium is prevalent. Scientists and farmers have developed efficient strategies to monitor and treat these dietary deficiencies. Supplementation methods suited to grazing livestock include long-acting injections, slow-release intraruminal boluses, trace element-amended fertilisers, and reticulated water supplies on dairy farms.

Grace, Neville D.; Knowles, Scott O.

2012-01-01

41

Vitamin and trace element supplementation in grazing dairy ewe during the dry season: effect on milk yield, composition, and clotting aptitude.  

PubMed

A study was carried out to evaluate the influence of vitamin and trace mineral supplementation on milk production and composition in grazing dairy ewes during the dry season. Ewes (n?=?50) were assigned at weaning to blocks and treatments. Ewes were daily conducted (8 h/day) on a pasture based on Italian ryegrass (Lolium multiflorum). At fold, ewes received a basal diet composed by ad libitum oat hay and a definite amount of a pelleted concentrate. Dietary treatments included: (1) the control concentrate containing background of vitamin and trace mineral only, and (2) the experimental concentrate containing the premix supplement (10 g/kg of dry matter). Vitamin and trace mineral supplementation did not affect ewes' body weight. Milk, fat- and protein-corrected milk, fat percentage, and clotting properties were improved in ewes fed supplemented concentrate. There was a week?×?treatment interaction (P?grazing dairy ewe, the dietary vitamin and trace mineral supplementation during dry season led to an increase of milk production and quality, with positive improvement in milk clotting aptitude. PMID:21331497

Tufarelli, Vincenzo; Khan, R U; Laudadio, Vito

2011-06-01

42

The effect of starch-, fiber-, or sugar-based supplements on nitrogen utilization in grazing dairy cows.  

PubMed

Nitrogen utilization in grazing cows is often low due to high concentrations of rapidly soluble and degradable protein in the pasture-based diet. Broadly, opportunities to improve N utilization lie in either reducing the amount of N consumed by the animal, or incorporating more N into milk protein. The goal of this study was to compare the relative importance of dietary N intake and productive N output for improving N utilization in grazing cows fed either starch-, fiber-, or sugar-based supplements. Also, the Cornell Net Carbohydrate and Protein System (CNCPS; Cornell University, Ithaca, NY) was evaluated as a tool to assess cow performance and improve N utilization in pasture-based systems. Eighty-five cows were randomly assigned to 1 of 5 treatments at parturition (17 cows per treatment). Treatments consisted of a pasture-only control and pasture with a starch- (St and StN), fiber- (FbN), or a sugar-based supplement. The StN and FbN treatments contained additional dietary N. Diets were formulated using the CNCPS to supply similar levels of dietary metabolizable energy, but differing levels of dietary N and metabolizable protein. Nitrogen utilization ranged from 22 to 26% across the 5 groups. Cows fed the St diet had the lowest levels of milk urea N, blood urea N, and urinary N excretion and had the highest productive N output (149 g/d). Cows fed the FbN treatment had similar productive N output (137 g/d) and consumed approximately 100g/d more dietary N than the St treatment, resulting in greater urinary N excretion. Although milk protein yield was moderately greater in the St treatment, quantitatively the difference in N intake (100g/d) had the greatest effect on N utilization and suggests that controlling dietary N intake should be the first priority when attempting to improve N utilization in grazing cows. No effect was observed of supplementing pasture-fed cattle with sugar on production or N utilization under the conditions of this experiment. Predictions of metabolizable energy and protein availability for milk yield from the CNCPS were similar to actual milk yield for all treatments. Model-predicted N utilization and excretion reflected the trends observed in the measured data and suggests that the CNCPS can be a useful tool for formulating and evaluating diets to improve N utilization in pasture-based systems. PMID:23548301

Higgs, R J; Sheahan, A J; Mandok, K; Van Amburgh, M E; Roche, J R

2013-06-01

43

Intensive dairy production systems in an urban landscape, the Dutch situation  

Microsoft Academic Search

Dairy production in the Netherlands is characterized by high stocking densities, high inputs of chemical fertilizer and concentrates and is facing multiple challenges on environment, landscape and welfare issues. This review focuses on nitrate, ammonia and methane emissions, and grazing. Emission reductions from dairy farms over the last twenty years have been realized by a combination of fundamental and applied

Th. V. Vellinga; A. Bannink; M. C. J. Smits; A. Van den Pol-Van Dasselaar; I. Pinxterhuis

2011-01-01

44

Evaluation of a Year-Round Grazing System: Winter Progress Report  

Microsoft Academic Search

The winter component of a year-round grazing system involving grazing of corn crop residues followed by grazing stockpiled grass-legume forages was compared at the McNay Research Farm with that of the winter component of a minimal land system that maintained cows in drylot. In the summers of 1995 and 1996, two and one cuttings of hay per year were harvested

Matthew J. Hersom; James R. Russell; Dennis R. Maxwell; L. J. Secor

1998-01-01

45

Evaluation of a Year-Round Grazing System: Winter Progress Report  

Microsoft Academic Search

The winter component of a year-round grazing system involving grazing of corn crop residues followed by grazing stockpiled grass legume forages was compared at the McNay Research Farm with that of the winter component of a minimal land system that maintained cows in drylot,. In the summer of 1995, two cuttings of hay were harvested from two 15-acre fields containing

Matthew J. Hersom; James R. Russell; Dennis R. Maxwell; L. J. Secor

1997-01-01

46

Differences in the epidemiology of theileriosis on smallholder dairy farms in contrasting agro-ecological and grazing strata of highland Kenya.  

PubMed Central

A prospective cohort study was conducted in five purposively-sampled agro-ecological zone (AEZ)-grazing system strata in Murang'a District, Kenya, between March 1995 and June 1996. The study strata were selected based on a preliminary characterization study to represent the widest range of risks to East Coast fever (ECF) in the District and included zero-grazing and open-grazing farms. In total, 225 calves from 188 smallholder farms were examined from birth to 6 months of age and visited within the first 2 weeks of life and thereafter at bi-weekly intervals for up to 14 visits. The purpose of the study was to characterize the differences in epidemiology (risks of infection, morbidity and mortality) and potential control of ECF between the selected strata. Evidence of Theileria parva infection was assessed by increased antibody levels as measured in an indirect ELISA assay by the percent positivity (PP) of serum samples relative to a strong positive reference serum. Sero-conversion risks of T. parva were highest in the open-grazing strata. Antibody prevalence in adult cattle and ECF morbidity and mortality risks were also highest in open-grazing strata. While different, all five AEZ-grazing strata were considered to be endemically unstable for ECF. East Coast fever challenge was low in all zero-grazing strata and this challenge is likely to remain low due to continuing intensification of smallholder farming in the central highlands. In the open-grazing strata, there was higher challenge and a greater impact of ECF.

Gitau, G. K.; McDermott, J. J.; Katende, J. M.; O'Callaghan, C. J.; Brown, R. N.; Perry, B. D.

2000-01-01

47

Differences in the epidemiology of theileriosis on smallholder dairy farms in contrasting agro-ecological and grazing strata of highland Kenya.  

PubMed

A prospective cohort study was conducted in five purposively-sampled agro-ecological zone (AEZ)-grazing system strata in Murang'a District, Kenya, between March 1995 and June 1996. The study strata were selected based on a preliminary characterization study to represent the widest range of risks to East Coast fever (ECF) in the District and included zero-grazing and open-grazing farms. In total, 225 calves from 188 smallholder farms were examined from birth to 6 months of age and visited within the first 2 weeks of life and thereafter at bi-weekly intervals for up to 14 visits. The purpose of the study was to characterize the differences in epidemiology (risks of infection, morbidity and mortality) and potential control of ECF between the selected strata. Evidence of Theileria parva infection was assessed by increased antibody levels as measured in an indirect ELISA assay by the percent positivity (PP) of serum samples relative to a strong positive reference serum. Sero-conversion risks of T. parva were highest in the open-grazing strata. Antibody prevalence in adult cattle and ECF morbidity and mortality risks were also highest in open-grazing strata. While different, all five AEZ-grazing strata were considered to be endemically unstable for ECF. East Coast fever challenge was low in all zero-grazing strata and this challenge is likely to remain low due to continuing intensification of smallholder farming in the central highlands. In the open-grazing strata, there was higher challenge and a greater impact of ECF. PMID:10813159

Gitau, G K; McDermott, J J; Katende, J M; O'Callaghan, C J; Brown, R N; Perry, B D

2000-04-01

48

Ecohydrological Relationships in Dryland Grazing Systems of the Sahel  

NASA Astrophysics Data System (ADS)

In water-limited environments like the Sahel, rangelands function as strongly coupled ecological-hydrological systems. Rainfall and soil moisture availability are the main forces driving vegetation structure and composition, and vegetation exerts strong controls on the redistribution and infiltration of rainfall. The presence and duration of surface waters in the landscape, however, determines livestock access to and consumption of pasture resources, with feedbacks on vegetation structure and ecohydrology. In this study, we use the Tree Grass Vegetation Model (TGVM) to study the interactions between climate, vegetation, grazing and lake volume in the watersheds surrounding 260 ponds in the Sahel. Analyses focus on 4 regions (Southwestern Niger, Eastern Mali, Western Mali and Northern Senegal) representing a range of bioclimatic, edaphic and land use conditions and were performed during the period 1972-2011. Unsupervised land cover classification maps using Landsat time series data were used to provide soil information, assuming a strong correlation between vegetation type and the underlying soil type, and the curve number method was used to estimate runoff during rainfall. We will explore the socio-ecohydrological relationships in response to grazing disturbances and climate variability, and discuss how feedbacks mediated by anthropogenic control of herbivore density could be significant for the sustainable management of Sahelian and other dryland regions.

Kaptue, A.; Prihodko, L.; Hanan, N. P.

2013-12-01

49

Utilization of Bt corn residues by grazing beef steers and Bt corn silage and grain by growing beef cattle and lactating dairy cows.  

PubMed

Three experiments were conducted to evaluate the impact of the Bacillus thuringiensis (Bt)-11 transformation event in two parental corn hybrids differing in date of maturity on beef and dairy cattle performance. Sixteen lactating Holstein dairy cows in replicated 4 x 4 Latin squares were assigned to four diets in a 2 x 2 factorial arrangement: Bt vs non-Bt trait and early- vs late-maturing corn hybrids. The diets contained 40% of the test corn silage plus 28% corn grain from the same corn hybrid (DM basis). There was no effect of the Bt trait on efficiency of milk production, ruminal pH, acetate:propionate ratio, or in situ digestion kinetics of NDF. The early-maturing corn hybrids resulted in greater total VFA concentrations in the rumen and efficiency of 4% fat-corrected milk production than the later-maturing hybrids (P < 0.05). Sixty-seven steer calves were used in a 70-d corn residue grazing trial for the late-maturing corn hybrids only. Daily BW gain of steers was similar for those grazing Bt and non-Bt corn residues, and the steers exhibited no grazing preference between Bt and non-Bt corn residue. One hundred twenty-eight steer calves were assigned to four silage-based growing diets in a 2 x 2 factorial arrangement: Bt vs non-Bt trait and early- vs late-maturing corn hybrids. The diets contained 90% corn silage and 10% supplement (DM basis). The DMI was higher for steers fed Bt compared with non-Bt hybrids (P < 0.02). An interaction (P < 0.03) was observed for feed efficiency between hybrid genotype and incorporation of the Bt trait. Feed efficiency was greater (P < 0.05) for steers fed the later-maturing non-Bt hybrid compared with the later-maturing Bt hybrid; however, feed efficiency was similar between steers fed early-maturing Bt and non-Bt corn silages. Steers fed the early-maturing hybrid gained 11% faster and were 7% more efficient compared with those fed the late-maturing hybrid. These latter results agree with the dairy experiment in which the early-maturing hybrid resulted in 5% greater efficiency of milk production than the later-maturing corn hybrid. In all experiments, incorporation of the Bt trait into corn had no consistent effect on cattle performance. In addition, background genetics of the corn hybrids appeared to have a more consistent impact on performance than did presence of the Bt trait. PMID:12019625

Folmer, J D; Grant, R J; Milton, C T; Beck, J

2002-05-01

50

Computerized Control System for Static Pile Composting of Dairy Manure  

Microsoft Academic Search

The Solid Aerobic Biodrying (SAB) system was developed and installed on an 85-cow dairy in the New York City drinking supply watershed. The SAB uses the static pile composting method to treat the dairy manure for land application or off farm sale. An automatic computerized control system was developed to maintain appropriate temperatures of the compost piles while optimizing for

51

Simulating detection of cattle-fever tick ( Boophilus spp.) infestations in rotational grazing systems  

Microsoft Academic Search

To evaluate the relative influence of ecological and management factors on the probability of detecting cattle-fever tick (Boophilus microplus and Boophilus annulatus) infestations in rotational grazing systems, we adapted a simulation model of Teel et al. [J. Range Manage. 51 (1998) 501] that examines interactions among Boophilus ticks, cattle, and habitat type under rotational grazing systems developed for semi-arid shrublands

M. S. Corson; P. D. Teel; W. E. Grant

2003-01-01

52

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

PubMed

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. PMID:25026955

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

2014-01-01

53

Characterisation of smallholder dairy production systems using animal welfare and milk quality.  

PubMed

The aim of the current study was to characterise and evaluate production system of smallholder dairy farmers using an index based on combined score of animal welfare and milk quality. Farms were grouped into three categories, tier 1, tier 2 and tier 3. To test the robustness of the characterisation, milk yield (MY), calving interval (CI) and body condition scores (BCS) were used. In the study area, the majority (66.3%) of smallholder dairy farmers practiced cut-and-carry as compared to 15.3% who grazed their cows. The rest combined cut-and-carry and grazing. Cows of farmers in tier 1 had the lowest mean MY (5.4 kg/day, SE = 0.4), lowest mean BCS (2.1 kg/day, SE = 0.09) and longest mean CI (603 days, SE = 27) than farmers in tier 3, mean MY (10.8 kg/day, SE = 0.6), mean BCS (2.6, SE = 0.06) and mean CI (404 days, SE = 17). The study demonstrated that a simple and yet novel method based on farm level indicators can be developed and could assist to timely identify specific problems on the farm. PMID:22290501

Kawonga, Bettie S; Chagunda, Mizeck G G; Gondwe, Timothy N; Gondwe, Sera R; Banda, James W

2012-10-01

54

Energy Integrated Dairy Farm digester and cogeneration system installation  

SciTech Connect

Georgia Tech finished in December, 1983 Phase II (system installation and startup) of its four year Energy Integrated Dairy Farm System (EIDFS) program. This paper outlines the selection and installation of the anaerobic digestion and cogeneration components of the EIDFS.

Ross, C.C.; Walsh, J.L.

1984-01-01

55

Grazing bifurcation in aeroelastic systems with freeplay nonlinearity  

NASA Astrophysics Data System (ADS)

A nonlinear analysis is performed to characterize the effects of a nonsmooth freeplay nonlinearity on the response of an aeroelastic system. This system consists of a plunging and pitching rigid airfoil supported by a linear spring in the plunge degree of freedom and a nonlinear spring in the pitch degree of freedom. The nonsmooth freeplay nonlinearity is associated with the pitch degree of freedom. The aerodynamic loads are modeled using the unsteady formulation. Linear analysis is first performed to determine the coupled damping and frequencies and the associated linear flutter speed. Then, a nonlinear analysis is performed to determine the effects of the size of the freeplay gap on the response of the aeroelastic system. To this end, two different sizes are considered. The results show that, for both considered freeplay gaps, there are two different transitions or sudden jumps in the system's response when varying the freestream velocity (below linear flutter speed) with the appearance and disappearance of quadratic nonlinearity induced by discontinuity. It is demonstrated that these sudden transitions are associated with a tangential contact between the trajectory and the freeplay boundaries (grazing bifurcation). At the first transition, it is demonstrated that increasing the freestream velocity is accompanied by the appearance of a superharmonic frequency of order 2 of the main oscillating frequency. At the second transition, the results show that an increase in the freestream velocity is followed by the disappearance of the superharmonic frequency of order 2 and a return to a simple periodic response (main oscillating frequency).

Vasconcellos, R.; Abdelkefi, A.; Hajj, M. R.; Marques, F. D.

2014-05-01

56

Ruminal Digestion by Dairy Cows Grazing Winter Oats Pasture Supplemented with Different Levels and Sources of Protein  

Microsoft Academic Search

Six Holstein cows fitted with ruminal cannulae were used in two simultaneous 3 × 3 Latin squares to study the effects of protein supplements on ruminal fermenta- tion and in situ crude protein degradability. Cows rota- tionally grazed a winter oats (Avena sativa L.) pasture and were supplemented with one of three concentrate supplements: 1) low protein sunflower meal (L-SM);

F. Bargo; D. H. Rearte; F. J. Santini; L. D. Muller

2001-01-01

57

Relationships among rotational and conventional grazing systems, stream channels, and macroinvertebrates  

USGS Publications Warehouse

Cattle grazing in riparian areas can reduce water quality, alter stream channel characteristics, and alter fish and macroinvertebrate assemblage structure. The U.S. Department of Agriculture, Natural Resources Conservation Services has recommended Rotational Grazing (RG) as an alternative management method on livestock and dairy operations to protect riparian areas and water quality. We evaluated 13 stream channel characteristics, benthic macroinvertebrate larvae (BML), and chironomid pupal exuviae (CPE) from 18 sites in the Upper Midwest of the United States in relation to RG and conventional grazing (CG). A Biotic Composite Score comprised of several macroinvertebrate metrics was developed for both the BML assemblage and the CPE assemblage. Multi-Response Permutation Procedures (MRPP) indicated a significant difference in stream channel characteristics between RG and CG. Nonmetric Multidimensional Scaling indicated that RG sites were associated with more stable stream banks, higher quality aquatic habitat, lower soil compaction, and larger particles in the streambed. However, neither MRPP nor Mann-Whitney U tests demonstrated a difference in Biotic Composite Scores for BML or CPE along RG and CG sites. The BML and CPE metrics were significantly correlated, indicating that they were likely responding to similar variables among the study sites. Although stream channel characteristics appeared to respond to grazing management, BML and CPE may have responded to land use throughout the watershed, as well as local land use. ?? 2011 Springer Science+Business Media B.V. (outside the USA).

Raymond, K. L.; Vondracek, B.

2011-01-01

58

Wavefront Sensing Analysis of Grazing Incidence Optical Systems  

NASA Technical Reports Server (NTRS)

Wavefront sensing is a process by which optical system errors are deduced from the aberrations in the image of an ideal source. The method has been used successfully in near-normal incidence, but not for grazing incidence systems. This innovation highlights the ability to examine out-of-focus images from grazing incidence telescopes (typically operating in the x-ray wavelengths, but integrated using optical wavelengths) and determine the lower-order deformations. This is important because as a metrology tool, this method would allow the integration of high angular resolution optics without the use of normal incidence interferometry, which requires direct access to the front surface of each mirror. Measuring the surface figure of mirror segments in a highly nested x-ray telescope mirror assembly is difficult due to the tight packing of elements and blockage of all but the innermost elements to normal incidence light. While this can be done on an individual basis in a metrology mount, once the element is installed and permanently bonded into the assembly, it is impossible to verify the figure of each element and ensure that the necessary imaging quality will be maintained. By examining on-axis images of an ideal point source, one can gauge the low-order figure errors of individual elements, even when integrated into an assembly. This technique is known as wavefront sensing (WFS). By shining collimated light down the optical axis of the telescope and looking at out-of-focus images, the blur due to low-order figure errors of individual elements can be seen, and the figure error necessary to produce that blur can be calculated. The method avoids the problem of requiring normal incidence access to the surface of each mirror segment. Mirror figure errors span a wide range of spatial frequencies, from the lowest-order bending to the highest order micro-roughness. While all of these can be measured in normal incidence, only the lowest-order contributors can be determined through this WFS technique.

Rohrbach, Scott; Saha, Timo

2012-01-01

59

Strategic Planning Study of the Dairy Herd Improvement System.  

National Technical Information Service (NTIS)

This report provides an overview and strategic planning study of the dairy herd improvement (DHI) system, concentrating on assessing current trends and conditions of the industry and how DHI organizations are structured within it. Information is provided ...

J. J. Wadsworth

1996-01-01

60

Emergy evaluation of contrasting dairy systems at multiple levels.  

PubMed

Emergy accounting (EmA) was applied to a range of dairy systems, from low-input smallholder systems in South Mali (SM), to intermediate-input systems in two regions of France, Poitou-Charentes (PC) and Bretagne (BR), to high-input systems on Reunion Island (RI). These systems were studied at three different levels: whole-farm (dairy system and cropping system), dairy-system (dairy herd and forage land), and herd (animals only). Dairy farms in SM used the lowest total emergy at all levels and was the highest user of renewable resources. Despite the low quality of resources consumed (crop residues and natural pasture), efficiency of their use was similar to that of industrialised inputs by intensive systems in RI, PC and BR. In addition, among the systems studied, SM dairy farms lay closest to environmental sustainability, contradicting the usual image of high environmental impact of cattle production in developing countries. EmA also revealed characteristics of the three intensive systems. Systems from RI and PC had lower resource transformation efficiency and higher environmental impacts than those from BR, due mainly to feeding strategies that differed due to differing socio-climatic constraints. Application of EmA at multiple levels revealed the importance of a multi-level analysis. While the whole-farm level assesses the overall contribution of the system to its environment, the dairy-system level is suitable for comparison of multi-product systems. In contrast, the herd level focuses on herd management and bypasses debates about definition of system boundaries by excluding land management. Combining all levels highlights the contribution of livestock to the global agricultural system and identifies inefficiencies and influences of system components on the environment. PMID:23792889

Vigne, Mathieu; Peyraud, Jean-Louis; Lecomte, Philippe; Corson, Michael S; Wilfart, Aurélie

2013-11-15

61

Genotype effects on body temperature in dairy cows under grazing conditions in a hot climate including evidence for heterosis  

Microsoft Academic Search

We compared diurnal patterns of vaginal temperature in lactating cows under grazing conditions to evaluate genotype effects\\u000a on body temperature regulation. Genotypes evaluated were Holstein, Jersey, Jersey × Holstein and Swedish Red × Holstein. The\\u000a comparison of Holstein and Jersey versus Jersey × Holstein provided a test of whether heterosis effects body temperature regulation.\\u000a Cows were fitted with intravaginal temperature

S. Dikmen; L. Martins; E. Pontes; P. J. Hansen

2009-01-01

62

Energy integrated dairy farm system in New York: Final report  

SciTech Connect

This technical manual was developed from the experiences and results gained from Cornell University's Energy Integrated Dairy System Project (EIDS). Goal of the project was to reduce fossil fuels and fossil fuel-based inputs into an income producing dairy farm by substituting energy efficient processes and practices for energy-intensive ones, and using solar-based energy sources - wind, active solar, and biomass.

Walker, L.P.; Ludington, D.C.; Merrill, W.G.; Pellerin, R.A.; Reid, W.S.; Space, R.; Space, R. II; White, S.A.; Heisler, M.G.; Farmer, G.S.

1985-09-01

63

Modelling Parasite Transmission in a Grazing System: The Importance of Host Behaviour and Immunity  

PubMed Central

Parasitic helminths present one of the most pervasive challenges to grazing herbivores. Many macro-parasite transmission models focus on host physiological defence strategies, omitting more complex interactions between hosts and their environments. This work represents the first model that integrates both the behavioural and physiological elements of gastro-intestinal nematode transmission dynamics in a managed grazing system. A spatially explicit, individual-based, stochastic model is developed, that incorporates both the hosts’ immunological responses to parasitism, and key grazing behaviours including faecal avoidance. The results demonstrate that grazing behaviour affects both the timing and intensity of parasite outbreaks, through generating spatial heterogeneity in parasite risk and nutritional resources, and changing the timing of exposure to the parasites’ free-living stages. The influence of grazing behaviour varies with the host-parasite combination, dependent on the development times of different parasite species and variations in host immune response. Our outputs include the counterintuitive finding that under certain conditions perceived parasite avoidance behaviours (faecal avoidance) can increase parasite risk, for certain host-parasite combinations. Through incorporating the two-way interaction between infection dynamics and grazing behaviour, the potential benefits of parasite-induced anorexia are also demonstrated. Hosts with phenotypic plasticity in grazing behaviour, that make grazing decisions dependent on current parasite burden, can reduce infection with minimal loss of intake over the grazing season. This paper explores how both host behaviours and immunity influence macro-parasite transmission in a spatially and temporally heterogeneous environment. The magnitude and timing of parasite outbreaks is influenced by host immunity and behaviour, and the interactions between them; the incorporation of both regulatory processes is required to fully understand transmission dynamics. Understanding of both physiological and behavioural defence strategies will aid the development of novel approaches for control.

Fox, Naomi J.; Marion, Glenn; Davidson, Ross S.; White, Piran C. L.; Hutchings, Michael R.

2013-01-01

64

Effect of agro-ecological zone and grazing system on incidence of East Coast Fever in calves in Mbale and Sironko Districts of Eastern Uganda.  

PubMed

Between May 2002 and February 2003 a longitudinal survey was carried out in Mbale and Sironko Districts of Eastern Uganda to determine the influence of agro-ecological zones (AEZ) and grazing systems on tick infestation patterns and incidence of East Coast Fever (ECF) in bovine calves. The study area was stratified into AEZ (lowland, midland and upland) and grazing systems {zero grazing (ZG), restricted-outdoor grazing (ROG) and communal grazing (CG)}, whose strata had previously been shown to influence the prevalence of ECF, babesiosis and anaplasmosis. One hundred and eighty-five smallholder dairy farms with a total of 198 calves of both sexes, between the ages of 1 day and 6 weeks, were purposively selected from the AEZ-grazing system strata. Nine dynamic cohorts (11-51 calves in each) of these calves were examined and sampled monthly. Ticks infesting the calves were counted from one side of the animal body and categorized into the different species, sex and feeding status. Sera were collected at recruitment and monthly thereafter and antibodies against Theileria parva, T. mutans, Babesia bigemina, B. bovis and Anaplasma marginale were measured using ELISA. Tick challenge (total and specific) varied with AEZ and grazing system. The risk of infection with T. parva was higher in the lowland zone compared to the upland zone (hazard ratio (HR)=2.59; 95% CI: 1.00-6.34). The risk of infection with T. parva was higher in the CG system than the ZG system (HR=10.00; 95% CI: 3.61-27.92). The incidence risk for sero-conversion, over the 10 months study period, was 62, 16 and 9% in the lowland, midland and upland zones, respectively. Ninety-eight percent of the calves in lowland-CG stratum sero-converted by the age of 6 months, while 56 and 8% did so in the lowland-ROG and the lowland-ZG stratum, respectively. The results of this study show the need to consider farm circumstances and the variation in ECF risk, both spatially and temporally when designing control strategies for ECF. PMID:16797092

Rubaire-Akiiki, Christopher M; Okello-Onen, Joseph; Musunga, David; Kabagambe, Edmond K; Vaarst, Mettee; Okello, David; Opolot, Charles; Bisagaya, A; Okori, C; Bisagati, C; Ongyera, S; Mwayi, M T

2006-08-17

65

The Dairy Technology System in Venezuela. Summary of Research 79.  

ERIC Educational Resources Information Center

A study examined the agricultural technology system in Venezuela with emphasis on the dairy industry. An analytical framework was used to identify the strengths and weaknesses of the following components of Venezuela's agricultural technology system: policy, technology development, technology transfer, and technology use. Selected government…

Nieto, Ruben D.; Henderson, Janet L.

66

Effect of supplemental concentrate type on milk production and metabolic status in early-lactation dairy cows grazing perennial ryegrass-based pasture.  

PubMed

Forty-four early-lactation dairy cows of mixed parity were used to examine the effect of 4 supplemental concentrate types (n=11) on milk production and metabolic status. Animals were blocked by parity and calving date, and blocks were balanced for previous milk yield and milk protein yield. Cows received grazed pasture plus 5.17 kg of DM/d of 1 of the following isoenergetic (1.1 units of energy for lactation) concentrates: 1) high crude protein (CP) with rolled barley (HP, 19% CP); b) low CP with rolled barley (LP, 15% CP); c) low CP with barley and a supplemental methionine hydroxy analog (HMBi; LP + HMBi, 15% CP); and d) low CP with ground corn (LP-corn, 15% CP). Milk yield was recorded from d 1 to 100 postpartum, with weekly milk sampling, body weight, and body condition score (BCS) measurements. Blood and rumen sampling were conducted weekly from wk 2 to 6 postpartum. Milk yield was lower for cows in the LP treatment compared with those offered other concentrate types (25.2 vs. 27.5 ± 0.39 kg/d). Animals in the HP group had a higher milk yield than those in the LP + HMBi group (28.2 vs. 26.8 ± 0.39 kg/d). Milk fat yield was lower from animals in the LP-corn group compared with those in the LP + HMBi group (0.94 vs. 1.03 ± 0.03 kg/d). Milk protein yield was lower in the LP group compared with those in the HP group (0.88 vs. 0.97 ± 0.02 kg/d). Animal body weight, BCS, and BCS loss were not affected by concentrate type. However, nonesterified fatty acids were higher from animals in the HP group than for those in the LP + HMBi group (0.41 vs. 0.33 ± 0.03 mmol/L), and ?-hydroxy butyric acid was higher from animals in the HP group than for those in the other treatments (0.71 vs. 0.59 ± 0.03 mmol/L). Glucose was higher from animals in the LP-corn group than for those in the HP and LP groups (3.3 vs. 3.2 ± 0.05 mmol/L). Blood urea-N was higher from animals offered HP compared with those offered the other treatments (5.49.6 vs. 4.21 ± 0.44 mmol/L). However, rumen NH(3)-N and volatile fatty acid concentration in the rumen were not affected by supplemental concentrate type. Reducing supplemental concentrate CP reduced milk yield. However, milk fat production and energy-corrected milk were not different, reducing the likelihood of an improved energy balance or a more favorable blood metabolic profile in early-lactation dairy cows grazing perennial ryegrass. Offering HMBi with low-CP concentrates or replacing rolled barley with ground maize improves milk production relative to low-CP concentrates and metabolic status relative to high-CP concentrates. PMID:22818468

Whelan, S J; Pierce, K M; Flynn, B; Mulligan, F J

2012-08-01

67

Mapping the social landscape of grazing management in the Corn Belt: A review of research and stakeholder perceptions of the multifunctionality of Iowa grazing systems  

Microsoft Academic Search

Agricultural systems that incorporate perennials in the form of grassland pasture have consistently been lauded for the balance of ecological and economic performance they provide, both at the farm and landscape level. The multiple functions grazing systems provide are being explored in increasing detail as ways to mitigate negative externalities associated with expanding commodity crop production. This thesis work provides

Mae Rose Petrehn

2011-01-01

68

System approach to grazing in desert ecosystems: A case study in Saudi Arabia  

Microsoft Academic Search

SUMMARY - This paper highlights a system approach to grazing in a desert ecosystem used by the Range and Animal Development Research in the northern region of the Kingdom of Saudi Arabia. Various factors affecting plant and animal production in a high potential desert system (wadi bottom) are discussed. The use of cultural treatments for increased forage production, the effect

M. M. Mirreh

69

Pluri-energy analysis of livestock systems--a comparison of dairy systems in different territories.  

PubMed

This paper introduces a generic assessment method called pluri-energy analysis. It aims to assess the types of energy used in agricultural systems and their conversion efficiencies. Four types of energy are considered: fossil energy, gross energy contained in the biomass, energy from human and animal labor and solar energy. The method was applied to compare smallholder low-input dairy-production systems, which are common in developing countries, to the high-input systems encountered in OECD countries. The pluri-energy method is useful for analyzing the functioning of agricultural systems by highlighting their modes of energy management. Since most dairy systems in South Mali (SM) are low-input systems, they are primarily based on solar and labor energy types and do not require substantial fossil-energy inputs to produce milk. Farms in Poitou-Charentes (PC) and Bretagne (BR) show intermediate values of fossil-energy use for milk production, similar to that found in the literature for typical European systems. However, fossil-energy use for milk production is higher on PC than BR farms because of a higher proportion of maize silage in the forage area; grazing pastures are more common on BR farms. Farms on Reunion Island (RI) require a relatively large amount of fossil energy to produce milk, mainly because the island context limits the amount of arable land. Consequently, milk production is based on large imports of concentrated feed with a high fossil-energy cost. The method also enables assessment of fossil-energy-use efficiency in order to increase the performance of biological processes in agricultural systems. Comparing the low-input systems represented by SM to the high-input systems represented by RI, PC and BR, an increase in solar-energy conversion, and thus land productivity, was observed due to intensification via increased fossil-energy use. Conversely, though fossil-energy use at the herd level increased milk productivity, its effect on gross-energy conversion by the herd was less evident. Partitioning the total on-farm gross energy produced among animal co-products (milk, meat and manure) highlights the major functions of SM herds, which are managed to produce organic crop fertilizers. PMID:23666069

Vigne, Mathieu; Vayssières, Jonathan; Lecomte, Philippe; Peyraud, Jean-Louis

2013-09-15

70

Herbage intake by cattle on tarchonanthus veld in the Northern Cape as affected by stocking rate and grazing system  

Microsoft Academic Search

In a trial with young Bonsmara cattle, four different stocking rates (10, 7, 6 and 4 ha\\/large stock unit) were applied in both a rotational and continuous grazing system. Feed intake was estimated during spring, summer, autumn and winter for four consecutive years starting in 1977.Irrespective of the grazing system, feed intake declined with an increase in stocking rate. On

J H Fourie; E A N Engels; B R Roberts

1986-01-01

71

Milking efficiency for grazing dairy cows can be improved by increasing automatic cluster remover thresholds without applying premilking stimulation.  

PubMed

It was hypothesized that streamlined premilking stimulation routines are effective at reducing cow cluster-on time but are not required to maintain milk yield or quality when increasing the automatic cluster remover (ACR) threshold above 0.4 kg/min. This was tested by examining the effect of 3 premilking treatments and 4 ACR thresholds over an 11-wk period with 96 mixed-age New Zealand Friesian-Jersey cross cows during peak lactation. Three premilking treatments were chosen: attach cluster immediately (control), attach cluster immediately and apply 30s of mechanical stimulation (Stim), and remove 2 squirts of milk from each quarter and attach cluster (Strip). Four ACR milk flow rate thresholds were imposed: 0.2 kg/min (ACR2), 0.4 kg/min (ACR4), 0.6 kg/min (ACR6), and 0.8 kg/min (ACR8). Measurements included individual cow milk yield, cluster-on time, average milk flow rate, maximum milk flow rate, time to average milk flow rate, time from maximum milk flow rate to end of milking, and the milk flow rate and cumulative yield at predetermined intervals during each milking session. Milk composition and somatic cell count (SCC) were determined on composite milk samples, collected weekly. Postmilking strip yield was measured at the end of each treatment period. Cows receiving the Strip treatment had a 3 to 4% shorter cluster-on time than did cows on the control treatment, but cows receiving Stim were not different from the control cows. Milk yield, SCC, and postmilking strip yield were not different between the 3 premilking treatments. Cluster-on time of the ACR8 cows was 18 to 26% less than that of the ACR2 cows, but SCC and milk production variables did not differ between the 4 end-of-milking treatments, despite higher strip yields as the ACR threshold increased. Increasing the ACR threshold is an effective strategy to improve milking efficiency (cows milked per operator per hour) in situations where the work routine times of dairy operators can be accelerated. To achieve the greatest milking efficiency, clusters should be attached immediately without premilking manual or mechanical stimulation. PMID:23567056

Edwards, J P; Jago, J G; Lopez-Villalobos, N

2013-06-01

72

Feasibility of vermicomposting dairy biosolids using a modified system to avoid earthworm mortality  

Microsoft Academic Search

A laboratory study was conducted to examine the feasibility of vermicomposting dairy biosolids (dairy sludge), either alone or with either of the bulking agents ? cereal straw or wood shavings, using the epigeic earthworm ? Eisinea andrei. Earthworms added directly to these three substrates died within 48 hours. A system was developed to overcome the toxic effect of unprocessed dairy

R. Nogales; C. Elvira; E. Benítez; R. Thompson; M. Gomez

1999-01-01

73

Seroepidemiological study of Q fever in domestic ruminants in semi-extensive grazing systems  

Microsoft Academic Search

BACKGROUND: Q fever, a worldwide zoonotic disease caused by Coxiella burnetii, is endemic in northern Spain where it has been reported as responsible for large series of human pneumonia cases and domestic ruminants' reproductive disorders. To investigate pathogen exposure among domestic ruminants in semi-extensive grazing systems in northern Spain, a serosurvey was carried out in 1,379 sheep (42 flocks), 626

Francisco Ruiz-Fons; Ianire Astobiza; Jesus F. Barandika; Ana Hurtado; Raquel Atxaerandio; Ramon A. Juste; Ana L. Garcia-Perez

2010-01-01

74

Catastrophic vegetation dynamics and soil degradation in semi-arid grazing systems  

Microsoft Academic Search

When vegetation is drastically reduced as a result of drought or an increase in herbivore numbers, it does not simply recover if periods with normal rainfall follow or if herbivores are removed. These are commonly recognized catastrophic phenomena of semi-arid grazing systems in general and of the African Sahel in particular. The main aims of this thesis are to provide

M. Rietkerk

1998-01-01

75

High Nature Value (HNV) Grazing Systems in Europe: A Link between Biodiversity and Farm Economics  

Microsoft Academic Search

Large tracts of the European rural land, most frequently in the Less Favoured Areas (LFA) are devoted to low- input and Large Scale Grazing Systems (LSGS) under severe environmental constraints. A small part of the rural popula- tion strives to make a living under a risk of abandonment. Paradoxically, these areas harbour a great part of the European High Nature

Rafael Caballero

2007-01-01

76

Modeling the Potential Spatial Distribution of Beef Cattle Grazing Using a Geographic Information System  

NSDL National Science Digital Library

In this scientific article, authors Timothy G. Wade and others use Boolean logic and Geographic Information System (GIS) models to predict where beef cattle are most and least likely to graze (in Oregon). The resource was originally published in Journal of Arid Environments in 1998 [38(2):357-365].

77

Intensive grazing system for small ruminants in the Tropics: The French West Indies experience and perspectives  

Microsoft Academic Search

The French West Indies and Caribbean authorities have the objective of increasing small ruminant production to match market demand and develop local economies. This paper highlights research results obtained in the French West Indies over the last 25 years in small ruminant farming. The accumulated knowledge enabled the design of an intensive grazing system whose main characteristics are: (i) three

M. Mahieu; H. Archimède; J. Fleury; N. Mandonnet; G. Alexandre

2008-01-01

78

Partial replacement of corn grain with calcium salts of fatty acid in the concentrate fed to grazing primiparous and multiparous dairy cows  

Microsoft Academic Search

The effects of the partial replacement of corn grain with calcium salts of unsaturated fatty acids (CSFA) on milk yield and composition, milk?fatty acid profile and parameters linked to body lipid mobilisation were examined in 32 multiparous (MC) and 18 primiparous (PC) grazing cows in early lactation. Cows grazed a lucerne pasture and received a concentrate composed (DM basis) of

G. F. Schroeder; G. A. Gagliostro

2007-01-01

79

Participatory rural appraisal in smallholder dairy systems in Tunisia.  

PubMed

Participatory Rural Appraisal (PRA) was carried out by a multidisciplinary team on a total of 60 smallholder dairy farms in three different geographical areas of Tunisia. Farms with less than three cows were excluded. Those participating had between three and 10 cows. Average milk production ranged between 8 and 32 litres per cow per day. 70% or over of milk produced was sold off the farms. Average intercalving intervals--measured from month of calving only--ranged from 12.9 months to 19. Age at first calving varied from two to nearly three years. Most work was done by the families. PRA revealed that the farmers in all three regions perceived unbalanced nutrition, which included availability of forages, to be the most important constraint, followed by poor reproductive efficiency. Reseeding with new species was instituted for grazing and hay. Farmers from the different regions were taken on exchange visits to see how these approaches worked. Training in reproductive management and milking hygiene was introduced. Seasonal ration formulation depending on local forage analysis was instituted. Two farms are participating in a programme of evaluation of olive oil extraction by-product as a ruminant feed. Partial budget analysis of these interventions will be carried out. PMID:18265871

Rekhis, J; Saaidane, F; Laamouri, M; Ben Hamida, K; Mabrouk, W; Slimane, N

2007-12-01

80

Adaptation of forage legume species and cultivars under grazing in two extensive livestock systems in Italy  

Microsoft Academic Search

Legume-based pastures can increase the forage feeding value, the self-provision of protein sources and the sustainability of grazing systems. This 4-year study provided further knowledge on adaptation of forage legume species and cultivars for pasture sowing in extensive livestock systems of inland Italian areas. Three cultivars of lucerne (Medicago sativa L.), two of birdsfoot trefoil (Lotus corniculatus L.) and two

L. Pecetti; P. Annicchiarico; F. Battini; S. Cappelli

2009-01-01

81

BEEF SPECIES SYMPOSIUM: Potential limitations of NRC in predicting energetic requirements of beef females within western U.S. grazing systems.  

PubMed

Assessment of beef cow energy balance and efficiency in grazing-extensive rangelands has occurred on a nominal basis over short time intervals and has not accounted for the complexity of metabolic and digestive responses; behavioral adaptations to climatic, terrain, and vegetation variables; and documentation of the effects of nutrient form and supply to grazing cattle. Previous research using pen-fed cows demonstrated differences (P < 0.01) in efficiency of weight change ranging from 135 to 58 g/Mcal ME intake. Furthermore, variation in efficiency of ME use for tissue energy gain or loss ranged from 36% to 80%. In general, energy costs for maintenance, tissue accretion, and mobilization were greatest in Angus-based cows, intermediate in Brahman- and Hereford-based cows, and least in dairy-based cows. The most efficient cattle may reflect the types that are successful in semiarid grazing environments with low input management. Successful range cattle systems are likely the result of retention of animals that best adapted to the grazing environment and thus were potentially more efficient. Animals exposed to a variety of stressors may continually adapt, so energy expenditure is reduced and may tend to depart from the modeled beef cow in the 1996 NRC Beef Cattle Requirements. Critical factors comprising cow lifetime achievement, including reproductive success, disease resistance, and calf weaning weight, may be driven by cow total energy utilization in energy-limiting environments. Therefore, energy adjustments for adapted cattle within these landscapes and seasonal BW changes can alter seasonal NEm requirements. Evaluated studies indicate that in static grazing environments, NRC prediction fitness was improved compared with predictions from dynamic systems where cattle were influenced less by management and more by environmental conditions. Preliminary herd analyses cast doubt on the accuracy of NRC BCS descriptions representing NEm requirements of adapted females utilizing semiarid rangelands. Possible gaps are proposed that could be the basis for prediction inaccuracies. A more complete understanding of mechanisms contributing to productivity in the field than the current model predicts will improve future models to better simulate energetic accountability and subsequent female performance. PMID:24492551

Petersen, M K; Mueller, C J; Mulliniks, J T; Roberts, A J; DelCurto, T; Waterman, R C

2014-07-01

82

Waste management systems of dairy cattle farms in Japan.  

PubMed

Recently, the size of livestock farms in Japan has been expanding and the pollution from farm wastes has become a serious problem in rural areas. Therefore it is necessary to design treatment strategies and improve the recycling of livestock manure for sustainability of agriculture in Japan. The dairy cattle waste management systems were studied at dairy farms in Aomori prefecture and in Hokkaido, Japan. The four farms, typical for the respective regions in Japan, were investigated on the basis of the land and livestock size, housing, overall farm and waste management, type of machinery and a farm labour force. A statistical comparison was made for housing, milking and waste handling systems of dairy farms. One of the waste handling strategies was aerobic slurry treatment and land irrigation of the treated liquid fraction. Such methods began to solve some of waste management problems created since 1967 in grassland farming areas of Hokkaido. The irrigation system supplies water fertiliser and organic material to land as well as shortening the spreading times. It recycles livestock resources, increases the soil fertility and rationalizes the farm management. PMID:12201128

Shima, E; Svoboda, I F; Tsutsumi, S; Ohkubo, H

2002-01-01

83

Short-term application of prestimulation and increased automatic cluster remover threshold affect milking characteristics of grazing dairy cows in late lactation.  

PubMed

It was hypothesized that reducing cow cluster-on time by increasing automatic cluster remover (ACR) thresholds above 0.4 kg/min would require premilking stimulation of the mammary gland to maintain milk yield. This was tested by examining the interaction between 4 ACR thresholds and 3 premilking treatments over an 8-wk period with 96 mixed-age Friesian-Jersey cross cows being milked twice per day in late lactation (average production: 13.9 kg/d). The 3 premilking treatments were attach cluster immediately (control), attach cluster 60s after entering the dairy (delay), or remove 2 squirts of foremilk from each quarter and attach cluster 60s after entering the dairy (Prep). Four ACR thresholds were chosen, where the cluster was removed after the milk flow rate was less than 0.2 (ACR2), 0.4 (ACR4), 0.6 (ACR6), and 0.8 kg/min (ACR8). Measurements included individual cow milk yield, cluster-on time, average milk flow rate, maximum milk flow rate, time from cluster attachment to average milk flow rate, milk yield in the first 2 min, time from maximum milk flow rate to end of milking, and the milk flow rate at predetermined intervals during each milking session. Composite milk samples were collected weekly at a.m. and p.m. milkings to determine composition and somatic cell count (SCC). On 3 occasions during the experiment, postmilking strip yield was measured. No interactions were detected between premilking treatment and ACR threshold in any of the measured variables. Cows receiving the Prep treatment had a 5 to 9% shorter cluster-on time than the control treatment. Milk yield, SCC, postmilking strip yield, and maximum flow rate were not different between the 3 premilking treatments. Cluster-on time of the ACR8 cows was 21 to 29% less than ACR2, but SCC and milk production variables were not different between the 4 end-of-milking treatments despite higher strip yields as ACR threshold increased. Increasing ACR threshold offers the potential to reduce the duration of milking without detriment to overall productivity. The results of the premilking treatments indicate that to achieve the most efficient routine, the operator should attach clusters as close as possible to the first bail in rotary dairies to increase bail utilization in pasture-based systems. If cluster attachment can be sped up and ACR threshold lifted, significant potential exists to decrease herd milking duration and improve labor productivity. PMID:23332836

Edwards, J P; Jago, J G; Lopez-Villalobos, N

2013-03-01

84

Energy Integrated dairy Farm System in Puerto Rico  

SciTech Connect

Principles of energy-integrated farming were applied to the Rio Canas Dairy Farm, a privately-owned dairy farm and one of the largest dairy farms in Puerto Rico with a milking herd of 400 cows. Animal wastes were fed to two anaerobic digesters where methane gas was produced by bacterial degradation of organic material. The methane gas fueled an engine-generator to produce electricity for farm use and for sale to the public utility. The Wastes were partially stabilized by bacterial action with the digesters and the digester effluent passed to a liquid-solid separator. Solid fraction was composted and either used as bedding material for the cows or marketed as soil conditioner. The liquid fraction flowed to a storage pond and was used in the Greenfeed subsystem to fertilize forage crops for the cows. Estimated energy savings of the system were 1705 MBtu for the first two subsystems and 7,718 MBtu's for all three subsystems. Simple payback for the first two subsystems was very long (20 years) because facilities for effective manure recovery did not exist on the farm at the outset of the project, operational costs for manure collection were charged against the project, and system components were oversized. Including the Greenfeed subsystem, simple payback for the project was 8.2 years. Assuming that manure collection facilities and practices already existed and assuming proper sizing of all components, simple payback for the Anaerobic Digestion and Electrical Production subsystem and the Farm Waste Management subsystem was 5.8 years. Using data from this project, an estimate of the return on investment was projected for different herd sizes. Results suggested that for dairy farms with less than 500 cows, anaerobic digester systems are only marginally profitable.

Sasscer, D.S.; Morgan, T.O.

1986-10-01

85

Dairy Analytics and Nutrient Analysis (DANA) Prototype System User Manual  

SciTech Connect

This document is a user manual for the Dairy Analytics and Nutrient Analysis (DANA) model. DANA provides an analysis of dairy anaerobic digestion technology and allows users to calculate biogas production, co-product valuation, capital costs, expenses, revenue and financial metrics, for user customizable scenarios, dairy and digester types. The model provides results for three anaerobic digester types; Covered Lagoons, Modified Plug Flow, and Complete Mix, and three main energy production technologies; electricity generation, renewable natural gas generation, and compressed natural gas generation. Additional options include different dairy types, bedding types, backend treatment type as well as numerous production, and economic parameters. DANA’s goal is to extend the National Market Value of Anaerobic Digester Products analysis (informa economics, 2012; Innovation Center, 2011) to include a greater and more flexible set of regional digester scenarios and to provide a modular framework for creation of a tool to support farmer and investor needs. Users can set up scenarios from combinations of existing parameters or add new parameters, run the model and view a variety of reports, charts and tables that are automatically produced and delivered over the web interface. DANA is based in the INL’s analysis architecture entitled Generalized Environment for Modeling Systems (GEMS) , which offers extensive collaboration, analysis, and integration opportunities and greatly speeds the ability construct highly scalable web delivered user-oriented decision tools. DANA’s approach uses server-based data processing and web-based user interfaces, rather a client-based spreadsheet approach. This offers a number of benefits over the client-based approach. Server processing and storage can scale up to handle a very large number of scenarios, so that analysis of county, even field level, across the whole U.S., can be performed. Server based databases allow dairy and digester parameters be held and managed in a single managed data repository, while allows users to customize standard values and perform individual analysis. Server-based calculations can be easily extended, versions and upgrades managed, and any changes are immediately available to all users. This user manual describes how to use and/or modify input database tables, run DANA, view and modify reports.

Sam Alessi; Dennis Keiser

2012-10-01

86

Grazing patterns of copepods in the upwelling system off Peru  

Microsoft Academic Search

The amount of food eaten by copepods of three genera (estimated from chlorophyll and pheophytin in the guts of the animals) was measured to determine the depth and also the time of day of the maximum and minimum intensity of feeding. Copepods were taken with a large volume (800 liters .min-') pumping system at five depths (O-85 m) and twelve

CARL M. BOYD; SHARON L. SMITH; TIMOTHY J. COWLES

1980-01-01

87

Dairy Systems and Policies of Selected Western European Countries.  

National Technical Information Service (NTIS)

Most nations of Western Europe have highly developed dairy industries. The European Community (EC) and selected countries of Western Europe are faced with surplus milk output. Dairy programs have been developed and implemented throughout most of Western E...

1983-01-01

88

The effect of cattle grazing on soil physical and chemical properties in a silvopastoral system in the Peruvian Amazon  

Microsoft Academic Search

In a six-year-old peach palm (Bactris gasipaes) plantation, centrosema (Centrosema macrocarpum), a leguminous forage plant,\\u000a was established as a cover crop which was eventually grazed. This experiment was designed to monitor probable changes in soil\\u000a physical and chemical properties and measure peach palm fruit production and live-weight gain of cattle grazing this silvopastoral\\u000a system. The experiment was installed on land

L. A. Arevalo; J. C. Alegre; D. E. Bandy; L. T. Szott

1998-01-01

89

ANAEROBIC DIGESTION AND WETLAND TREATMENT CASE STUDY: COMPARING TWO MANURE ODOR CONTROL SYSTEMS FOR DAIRY FARMS  

Microsoft Academic Search

Summary: A comparison of two existing odor control treatments on dairy farms in NY shows the costs and benefits of each system. On one dairy farm an anaerobic digester is used to stabilize the manure and collect methane for the production of electricity. The effluent is then separated. The solids are sold, and the liquid effluent is then land applied.

Peter E. Wright; Stephen P. Perschke

1998-01-01

90

Incorporating a prediction of postgrazing herbage mass into a whole-farm model for pasture-based dairy systems.  

PubMed

The DairyNZ whole-farm model (WFM; DairyNZ, Hamilton, New Zealand) consists of a framework that links component models for animal, pastures, crops, and soils. The model was developed to assist with analysis and design of pasture-based farm systems. New (this work) and revised (e.g., cow, pasture, crops) component models can be added to the WFM, keeping the model flexible and up to date. Nevertheless, the WFM does not account for plant-animal relationships determining herbage-depletion dynamics. The user has to preset the maximum allowable level of herbage depletion [i.e., postgrazing herbage mass (residuals)] throughout the year. Because residuals have a direct effect on herbage regrowth, the WFM in its current form does not dynamically simulate the effect of grazing pressure on herbage depletion and consequent effect on herbage regrowth. The management of grazing pressure is a key component of pasture-based dairy systems. Thus, the main objective of the present work was to develop a new version of the WFM able to predict residuals, and thereby simulate related effects of grazing pressure dynamically at the farm scale. This objective was accomplished by incorporating a new component model into the WFM. This model represents plant-animal relationships, for example sward structure and herbage intake rate, and resulting level of herbage depletion. The sensitivity of the new version of the WFM was evaluated and then the new WFM was tested against an experimental data set previously used to evaluate the WFM and to illustrate the adequacy and improvement of the model development. Key outputs variables of the new version pertinent to this work (milk production, herbage dry matter intake, intake rate, harvesting efficiency, and residuals) responded acceptably to a range of input variables. The relative prediction errors for monthly and mean annual residual predictions were 20 and 5%, respectively. Monthly predictions of residuals had a line bias (1.5%), with a proportion of square root of mean square prediction error (RMSPE) due to random error of 97.5%. Predicted monthly herbage growth rates had a line bias of 2%, a proportion of RMSPE due to random error of 96%, and a concordance correlation coefficient of 0.87. Annual herbage production was predicted with an RMSPE of 531 (kg of herbage dry matter/ha per year), a line bias of 11%, a proportion of RMSPE due to random error of 80%, and relative prediction errors of 2%. Annual herbage dry matter intake per cow and hectare, both per year, were predicted with RMSPE, relative prediction error, and concordance correlation coefficient of 169 and 692kg of dry matter, 3 and 4%, and 0.91 and 0.87, respectively. These results indicate that predictions of the new WFM are relatively accurate and precise, with a conclusion that incorporating a plant-animal relationship model into the WFM allows for dynamic predictions of residuals and more realistic simulations of the effect of grazing pressure on herbage production and intake at the farm level without the intervention from the user. PMID:24835965

Gregorini, P; Galli, J; Romera, A J; Levy, G; Macdonald, K A; Fernandez, H H; Beukes, P C

2014-07-01

91

Grazing Rental Appraisal Data.  

National Technical Information Service (NTIS)

The 'Public Rangeland Improvement Act of 1978' required the Secretaries of Agriculture and the Department of Interior to conduct a study of grazing fees in the Western United States and make recommendations for alternative fee systems before January 1986....

C. E. Brownell P. B. Tittman G. Jackson

1983-01-01

92

Energy Integrated dairy Farm System in Puerto Rico  

Microsoft Academic Search

Principles of energy-integrated farming were applied to the Rio Canas Dairy Farm, a privately-owned dairy farm and one of the largest dairy farms in Puerto Rico with a milking herd of 400 cows. Animal wastes were fed to two anaerobic digesters where methane gas was produced by bacterial degradation of organic material. The methane gas fueled an engine-generator to produce

D. S. Sasscer; T. O. Morgan

1986-01-01

93

Effect of a hay-based diet or different upland grazing systems on milk volatile compounds.  

PubMed

The effect of animal feeding on milk volatile organic compounds (VOCs) of metabolic origin was tested on a hay-based diet (H), a highly diversified pasture under continuous grazing (CG), or a less diversified pasture under rotational grazing (RG). Individual milk of 24 Montbe?liarde cows (8 per treatment) were sampled after 2 weeks. Pasture-derived milk was richer (p < 0.05) in camphene, sabinene, ?-caryophyllene, and skatole than H milk. Neither milk yield nor fat content affected the majority of VOCs measured. Skatole increased slightly with milk yield, while indole and cineole decreased slightly with milk fat content but with poor regression (R(2) < 0.54). Multivariate analysis showed that, on the basis of those VOCs of metabolic origin whose concentration differed between treatment (dimethyl-sulfone, skatole, toluene, undecanoic acid, 1-octadecene, benzeneacetaldehyde, octanoic acid, and 2-pentanone-4-hydroxy-4-methyl), it was possible to obtain good discriminations among feeding systems. This study is promising for a future use of VOCs of metabolic origin to trace animal feeding systems. PMID:21434695

Coppa, Mauro; Martin, Bruno; Pradel, Philippe; Leotta, Barbara; Priolo, Alessandro; Vasta, Valentina

2011-05-11

94

Energy Integrated Dairy Farm System in North Dakota  

SciTech Connect

The EIFS project at North Dakota State University, located at Fargo, North Dakota, is an effort to show how a Northern Great Plains EIFS might be operated. This farm used a combination of energy conservation, energy capture, and energy production. Energy conservation was demonstrated using reduced tillage in a typical cropping system and by using heat reclamation equipment on the ventilation system and the milk cooler in the dairy barn. Energy capture was demonstrated with a solar collector used to preheat ventilation air. Energy production was demonstrated with the construction of an anaerobic digester to produce methane from manure. This manual describes the design, construction, operation, and performance of the EIFS developed at North Dakota State University.

Pratt, G.; Lindley, J.; Hirning, H.; Giles, J.

1986-11-01

95

The carbon footprint of dairy production systems through partial life cycle assessment.  

PubMed

Greenhouse gas (GHG) emissions and their potential effect on the environment has become an important national and international issue. Dairy production, along with all other types of animal agriculture, is a recognized source of GHG emissions, but little information exists on the net emissions from dairy farms. Component models for predicting all important sources and sinks of CH(4), N(2)O, and CO(2) from primary and secondary sources in dairy production were integrated in a software tool called the Dairy Greenhouse Gas model, or DairyGHG. This tool calculates the carbon footprint of a dairy production system as the net exchange of all GHG in CO(2) equivalent units per unit of energy-corrected milk produced. Primary emission sources include enteric fermentation, manure, cropland used in feed production, and the combustion of fuel in machinery used to produce feed and handle manure. Secondary emissions are those occurring during the production of resources used on the farm, which can include fuel, electricity, machinery, fertilizer, pesticides, plastic, and purchased replacement animals. A long-term C balance is assumed for the production system, which does not account for potential depletion or sequestration of soil carbon. An evaluation of dairy farms of various sizes and production strategies gave carbon footprints of 0.37 to 0.69kg of CO(2) equivalent units/kg of energy-corrected milk, depending upon milk production level and the feeding and manure handling strategies used. In a comparison with previous studies, DairyGHG predicted C footprints similar to those reported when similar assumptions were made for feeding strategy, milk production, allocation method between milk and animal coproducts, and sources of CO(2) and secondary emissions. DairyGHG provides a relatively simple tool for evaluating management effects on net GHG emissions and the overall carbon footprint of dairy production systems. PMID:20172247

Rotz, C A; Montes, F; Chianese, D S

2010-03-01

96

Explorative research into quality of slurry manure from dairy farms with different feeding strategies  

Microsoft Academic Search

To assess cattle slurry manure quality in relation to feeding strategy, a field experiment and a bio-assay were carried out with slurries from four dairy farming systems that used diets differing in protein content and digestibility. Several quality aspects were evaluated. In the field experiment the effects of slurry manure type on herbage rejection by grazing heifers and herbage yield

J. W. Reijs; W. H. Meijer; E. J. Bakker; E. A. Lantinga

2003-01-01

97

Cross-sectional prevalence of helminth infections in cattle on traditional, small-scale and large-scale dairy farms in Iringa district, Tanzania.  

PubMed

A cross-sectional study was carried out to determine the prevalence of gastrointestinal (GI) nematodes and flukes (Fasciola and amphistomes) infection in communally grazed traditional cattle, zero-grazed small-scale dairy cattle and intensively grazed large-scale dairy cattle through examination of helminth eggs in faeces. Results indicated that the type of management, especially the grazing habit, has a significant influence on the prevalence and intensity of GI nematodes and flukes. The prevalence of GI nematodes in traditional, large-scale dairy and small-scale dairy cattle was 67%, 44.4% and 37%, respectively, with the highest faecal egg counts in calves. The overall prevalence of Fasciola gigantica in traditional, large-scale dairy and small-scale dairy cattle was 63.8%, 46.2% and 28.4%, respectively. The prevalence of amphistomes was 81.9%, 55.5% and 41.1% in traditional, large-scale dairy and small-scale dairy cattle, respectively. The high prevalence of flukes in the traditional system was attributed to communal grazing and watering management practices. Stomach flukes recovered in examined cattle at the abattoir were Calicophoron microbothrium and Cotylophoron jacksoni. About 42.1% of infected animals had both Fasciola and amphistomes. The prevalence of both GI nematodes and flukes varied greatly among villages and farms. The prevalence of both Fasciola and amphistomes was higher in adults (58.5%, 75.2%) than in yearlings (36.5%, 51.5%) or calves (24.9%, 47.2%). The variation in the prevalence of both GI nematodes and flukes among management and age groups within systems can be used as an entry point towards rational use of anthelmintics for each management system. More studies on seasonal transmission pattern of all these parasites are required in order to design rational, economic and locally sustainable parasite control programmes. PMID:16362610

Keyyu, J D; Kassuku, A A; Msalilwa, L P; Monrad, J; Kyvsgaard, N C

2006-01-01

98

Description and validation of the Moorepark Dairy System Model.  

PubMed

A stochastic budgetary simulation model of a dairy farm was developed to allow investigation of the effects of varying biological, technical, and physical processes on farm profitability. The model integrates animal inventory and valuation, milk supply, feed requirement, land and labor utilization, and economic analysis. A key model output is the estimated distribution of farm profitability, which is a function of total receipts from milk, calves, and cull cows less all variable and fixed costs (including an imputed cost for labor). An application of the model was demonstrated by modeling 2 calving patterns: a mean calving date of February 24 (S1) and a mean calving date of January 27 (S2). Monte Carlo simulation was used to determine the influence of variation in milk price, concentrate cost, and silage quality on farm profitability under each scenario. Model validation was conducted by comparing the results from the model against data collected from 21 commercial dairy farms. The net farm profit with S1 was 53,547 euros, and that with S2 was 51,687 euros; the annual EU milk quota was 468,000 kg, and farm size was 40 ha. Monte Carlo simulation showed that the S1 scenario was stochastically dominant over the S2 scenario. Sensitivity analyses showed that farm profit was most sensitive to changes in milk price. The partial coefficients of determination were 99.2, 0.7, and 0.1% for milk price, concentrate cost, and silage quality, respectively, in S1; the corresponding values in S2 were 97.6, 2.3, and 0.1%. Validations of the model showed that it could be used with confidence to study systems of milk production under Irish conditions. PMID:15453512

Shalloo, L; Dillon, P; Rath, M; Wallace, M

2004-06-01

99

GRAZPLAN: Decision support systems for Australian grazing enterprises—II. The animal biology model for feed intake, production and reproduction and the GrazFeed DSS  

Microsoft Academic Search

This paper specifies the animal biology module of a model for simulating grazing systems for ruminants on pasture. The program predicts the intake of energy and protein, allowing for selective grazing and substitution by supplementary feeds, and estimates the use of the diet for maintenance and production, according to current feeding standards. Conception and death rates are predicted from the

M. Freer; A. D. Moore; J. R. Donnelly

1997-01-01

100

Seroepidemiological study of Q fever in domestic ruminants in semi-extensive grazing systems  

PubMed Central

Background Q fever, a worldwide zoonotic disease caused by Coxiella burnetii, is endemic in northern Spain where it has been reported as responsible for large series of human pneumonia cases and domestic ruminants' reproductive disorders. To investigate pathogen exposure among domestic ruminants in semi-extensive grazing systems in northern Spain, a serosurvey was carried out in 1,379 sheep (42 flocks), 626 beef cattle (46 herds) and 115 goats (11 herds). Serum antibodies were analysed by ELISA and positive samples were retested by Complement Fixation test (CFT) to detect recent infections. Results ELISA anti-C. burnetii antibody prevalence was slightly higher in sheep (11.8 ± 2.0%) than in goats (8.7 ± 5.9%) and beef cattle (6.7 ± 2.0%). Herd prevalence was 74% for ovine, 45% for goat and 43% for bovine. Twenty-one percent of sheep flocks, 27% of goat and 14% of cattle herds had a C. burnetii seroprevalence ? 20%. Only 15 out of 214 ELISA-positive animals reacted positive by CFT. Age-associated seroprevalence differed between ruminant species with a general increasing pattern with age. No evidence of correlation between abortion history and seroprevalence rates was observed despite the known abortifacient nature of C. burnetii in domestic ruminants. Conclusions Results reported herein showed that sheep had the highest contact rate with C. burnetii in the region but also that cattle and goats should not be neglected as part of the domestic cycle of C. burnetii. This work reports basic epidemiologic patterns of C. burnetii in semi-extensive grazed domestic ruminants which, together with the relevant role of C. burnetii as a zoonotic and abortifacient agent, makes these results to concern both Public and Animal Health Authorities.

2010-01-01

101

Grazing Soybean to Increase Voluntary Cow Traffic in a Pasture-based Automatic Milking System  

PubMed Central

Pasture-based automatic milking systems (AMS) require cow traffic to enable cows to be milked. The interval between milkings can be manipulated by strategically allocating pasture. The current experiment investigated the effect of replacing an allocation of grazed pasture with grazed soybean (Glycine max) with the hypothesis that incorporating soybean would increase voluntary cow traffic and milk production. One hundred and eighty mixed age, primiparous and multiparous Holstein-Friesian/Illawarra cows were randomly assigned to two treatment groups (n = 90/group) with a 2×2 Latin square design. Each group was either offered treatments of kikuyu grass (Pennisetum clandestinum Hoach ex Chiov.) pasture (pasture) or soybean from 0900 h to 1500 h during the experimental period which consisted of 2 periods of 3 days following 5 days of training and adaptation in each period with groups crossing over treatments after the first period. The number of cows trafficking to each treatment was similar together with milk yield (mean ?18 L/cow/d) in this experiment. For the cows that arrived at soybean or pasture there were significant differences in their behaviour and consequently the number of cows exiting each treatment paddock. There was greater cow traffic (more cows and sooner) exiting pasture allocations. Cows that arrived at soybean stayed on the allocation for 25% more time and ate more forage (8.5 kg/cow/d/allocation) relative to pasture (4.7 kg/cow/d/allocation). Pasture cows predominantly replaced eating time with rumination. These findings suggest that replacing pasture with alternative grazeable forages provides no additional incentive to increase voluntary cow traffic to an allocation of feed in AMS. This work highlights the opportunity to increase forage intakes in AMS through the incorporation of alternative forages.

Clark, C. E. F.; Horadagoda, A.; Kerrisk, K. L.; Scott, V.; Islam, M. R.; Kaur, R.; Garcia, S. C.

2014-01-01

102

Lamb eimeriosis: applied treatment protocols in dairy sheep production systems.  

PubMed

The effect of different treatment protocols using the triazinone compounds diclazuril and toltrazuril on Eimeria oocyst excretion, diarrhoea and weight gain was evaluated in the present study. The protocols were designed in order to best fit to common management practices in dairy production systems as applied in Greece. During the first two trials comparative preventive (11 days after birth) and therapeutic (18 days after birth) single treatments using either drug were performed on an intensive farm. In Trial 3 the efficacy of a repeated diclazuril treatment after weaning (at the start and 4 weeks later) of the animals in a semi-intensive farm was tested. The last trial was performed in order to assess the effect of a single oral dose of toltrazuril after weaning of the animals on the same farm. During an observation period of 6-7 weeks after treatment animals in all trials were clinically examined for diarrhoea and faecal samples were regularly monitored for Eimeria oocysts at weekly intervals. Body weight was also determined at the start and end of each trial. A single treatment with toltrazuril resulted in a significant reduction of oocyst excretion over the study period compared to the control, with very high efficacy values during the first 2-3 weeks after treatment, irrespective of the treatment protocol and the management system applied. This in general could not be confirmed in the protocols using diclazuril, which showed a much lower and mostly variable efficacy pattern. PMID:23428203

Saratsis, Anastasios; Karagiannis, Isidoros; Brozos, Christos; Kiossis, Evagellos; Tzanidakis, Nikolaos; Joachim, Anja; Sotiraki, Smaragda

2013-09-01

103

Impairment of O-antigen production confers resistance to grazing in a model amoeba-cyanobacterium predator-prey system  

PubMed Central

The grazing activity of predators on photosynthetic organisms is a major mechanism of mortality and population restructuring in natural environments. Grazing is also one of the primary difficulties in growing cyanobacteria and other microalgae in large, open ponds for the production of biofuels, as contaminants destroy valuable biomass and prevent stable, continuous production of biofuel crops. To address this problem, we have isolated a heterolobosean amoeba, HGG1, that grazes upon unicellular and filamentous freshwater cyanobacterial species. We have established a model predator–prey system using this amoeba and Synechococcus elongatus PCC 7942. Application of amoebae to a library of mutants of S. elongatus led to the identification of a grazer-resistant knockout mutant of the wzm ABC O-antigen transporter gene, SynPCC7942_1126. Mutations in three other genes involved in O-antigen synthesis and transport also prevented the expression of O-antigen and conferred resistance to HGG1. Complementation of these rough mutants returned O-antigen expression and susceptibility to amoebae. Rough mutants are easily identifiable by appearance, are capable of autoflocculation, and do not display growth defects under standard laboratory growth conditions, all of which are desired traits for a biofuel production strain. Thus, preventing the production of O-antigen is a pathway for producing resistance to grazing by certain amoebae.

Simkovsky, Ryan; Daniels, Emy F.; Tang, Karen; Huynh, Stacey C.; Golden, Susan S.; Brahamsha, Bianca

2012-01-01

104

An Integrated Approach to Modeling Grazing Pressure in Pastoral Systems: The Case of the Logone Floodplain (Cameroon)  

Microsoft Academic Search

The discussion about the impact of pastoral systems on ecosystems has been profoundly shaped by Hardin’s “tragedy of the commons”\\u000a argument that held pastoralists responsible for overgrazing the range. Recent studies have shown that grazing ecosystems are\\u000a much more complex and dynamic than was previously assumed and that pastoralists adaptively manage these systems. However,\\u000a we still have little understanding how

Mark Moritz; Eric Soma; Paul Scholte; Ningchuan Xiao; Leah Taylor; Todd Juran; Saïdou Kari

2010-01-01

105

The effect of extended grazing time and supplementary forage on the dry matter intake and foraging behaviour of cattle kept under traditional african grazing systems.  

PubMed

An experiment was carried out at Alemaya University in Ethiopia to investigate the effect of night kraaling on the dry matter intake (DMI), live weight gain (LWG) and foraging behaviour of Ogaden cattle. Three groups of four animals were given either 7 h access to pasture per day, simulating traditional grazing (TG) practice; extended grazing (EG) access for 11 h per day; or traditional grazing access plus a nocturnal forage supplement (TF). Live weight gain, DMI and foraging behaviour were measured during the late dry season (EP1) and the wet season (EP2). None of the treatments had any significant effect on either DMI or LWG during EP1 or EP2. Extending pasture access time from 7 h to 11 h did not significantly increase the amount time spent grazing, but grazing intensity was significantly (p < 0.05) reduced during the non-common grazing hours. Step rate was significantly lower (p < 0.01) during EP2 than during EP1 and bites per step were significantly higher (p < 0.001) during EP2 than EP1, indicating that animals had to travel a shorter distance before selecting material to eat during the wet season (EP2). Providing supplementary forage (TF) had no significant effect on any measured parameter. In this study neither of the two low-cost methods (EG and TF) of improving access to forage had any beneficial effect on cattle productivity. It is concluded that, under the prevailing conditions, the traditional grazing practices of this part of Ethiopia do provide sufficient pasture access time to achieve daily voluntary food intake. PMID:17405631

Smith, D G; Cuddeford, D; Pearson, R A

2006-01-01

106

The effect of improving cow productivity, fertility, and longevity on the global warming potential of dairy systems.  

PubMed

This study compared the environmental impact of a range of dairy production systems in terms of their global warming potential (GWP, expressed as carbon dioxide equivalents, CO(2)-eq.) and associated land use, and explored the efficacy of reducing said impact. Models were developed using the unique data generated from a long-term genetic line × feeding system experiment. Holstein-Friesian cows were selected to represent the UK average for milk fat plus protein production (control line) or were selected for increased milk fat plus protein production (select line). In addition, cows received a low forage diet (50% forage) with no grazing or were on a high forage (75% forage) diet with summer grazing. A Markov chain approach was used to describe the herd structure and help estimate the GWP per year and land required per cow for the 4 alternative systems and the herd average using a partial life cycle assessment. The CO(2)-eq. emissions were expressed per kilogram of energy-corrected milk (ECM) and per hectare of land use, as well as land required per kilogram of ECM. The effects of a phenotypic and genetic standard deviation unit improvement on herd feed utilization efficiency, ECM yield, calving interval length, and incidence of involuntary culling were assessed. The low forage (nongrazing) feeding system with select cows produced the lowest CO(2)-eq. emissions of 1.1 kg/kg of ECM and land use of 0.65 m(2)/kg of ECM but the highest CO(2)-eq. emissions of 16.1t/ha of the production systems studied. Within the herd, an improvement of 1 standard deviation in feed utilization efficiency was the only trait of those studied that would significantly reduce the reliance of the farming system on bought-in synthetic fertilizer and concentrate feed, as well as reduce the average CO(2)-eq. emissions and land use of the herd (both by about 6.5%, of which about 4% would be achievable through selective breeding). Within production systems, reductions in CO(2)-eq. emissions per kilogram of ECM and CO(2)-eq. emissions per hectare were also achievable by an improvement in feed utilization. This study allowed development of models that harness the biological trait variation in the animal to improve the environmental impact of the farming system. Genetic selection for efficient feed use for milk production according to feeding system can bring about reductions in system nutrient requirements, CO(2)-eq. emissions, and land use per unit product. PMID:21700056

Bell, M J; Wall, E; Russell, G; Simm, G; Stott, A W

2011-07-01

107

Greenhouse Gas Emission Reduction Associated with Livestock Waste Management Systems: A Case Study for the Langerwerf Dairy Waste Management System  

Microsoft Academic Search

By using anaerobic digestion (AD) technology, a 400-cow dairy farm near Durham, California has reduced greenhouse gas (GHG) emissions and global warming potential (GWP) by approximately four-fifths (79%). The dairy-waste management system at the farm incorporates an AD system that produces biogas, electricity and heat through the use of a combined heat and power unit. The analysis compared the GHG

Jane H. Turnbull; Wellam Kamthunzi

108

Response of a depleted sagebrush steppe riparian system to grazing control and woody plantings. Forest Service research paper  

SciTech Connect

To find out if a depleted riparian system in the sagebrush steppe of eastern Oregon would respond quickly to improved management, five management treatments were applied for 7 years, ranging from ungrazed to heavily grazed treatments, including, in some cases, planting of woody species. While the results varied, all treatments were too limited to significantly restore the damaged areas within the 7-year span. Although some improvements were made in woody plant densities, little meaningful change occurred in the frequencies of herbaceous wetland plants, densities of small wildlife, or stream channel morphology. We concluded the restoration would take many years, possibly decades, without increased revegetation efforts and continued reductions in grazing in this riparian system damaged over 150 years.

Clary, W.P.; Shaw, N.L.; Dudley, J.G.; Saab, V.A.; Kinney, J.W.

1996-12-01

109

Influence of stocking rate and grazing system on plant basal cover and botanical composition of veld in the northern cape  

Microsoft Academic Search

Changes in basal cover and botanical composition were recorded at four stocking rates, both under continuous and rotational grazing in the Northern Cape. The experiment was conducted with cattle. Results suggested that heavier stocking rates could be applied under rotational grazing than under continuous grazing without veld deterioration occuring. After four seasons, botanical composition deteriorated only under continuous grazing. Plant

J. H. Fourie; G. J. Redelinghuys; D. P. J. Opperman

1984-01-01

110

Global versus local environmental impacts of grazing and confined beef production systems  

NASA Astrophysics Data System (ADS)

Carbon footprint is a key indicator of the contribution of food production to climate change and its importance is increasing worldwide. Although it has been used as a sustainability index for assessing production systems, it does not take into account many other biophysical environmental dimensions more relevant at the local scale, such as soil erosion, nutrient imbalance, and pesticide contamination. We estimated carbon footprint, fossil fuel energy use, soil erosion, nutrient imbalance, and risk of pesticide contamination for five real beef background-finishing systems with increasing levels of intensification in Uruguay, which were combinations of grazing rangelands (RL), seeded pastures (SP), and confined in feedlot (FL). Carbon footprint decreased from 16.7 (RL-RL) to 6.9 kg (SP-FL) CO2 eq kg body weight-1 (BW; ‘eq’: equivalent). Energy use was zero for RL-RL and increased up to 17.3 MJ kg BW-1 for SP-FL. Soil erosion values varied from 7.7 (RL-RL) to 14.8 kg of soil kg BW-1 (SP-FL). Nitrogen and phosphorus nutrient balances showed surpluses for systems with seeded pastures and feedlots while RL-RL was deficient. Pesticide contamination risk was zero for RL-RL, and increased up to 21.2 for SP-FL. For the range of systems studied with increasing use of inputs, trade-offs were observed between global and local environmental problems. These results demonstrate that several indicators are needed to evaluate the sustainability of livestock production systems.

Modernel, P.; Astigarraga, L.; Picasso, V.

2013-09-01

111

Welfare-positive management and nutrition for the dairy herd: a European perspective.  

PubMed

As European dairy farms become larger and diverge between grass-based and fully housed systems, interest in the welfare of the dairy cow and related environmental issues by consumers and legislators is increasing. These pressures mean that good nutrition and management, which underpin much dairy cow welfare, is critical. Despite considerable research into the management and nutrition of the dairy cow from calf to adulthood there is much on-farm variability in its application. While the incidences of many endemic diseases are reduced most are still significant, for example lameness. In addition, trade and climate change are bringing a more diverse range of pathogens, parasites and pests into Northern Europe. Housing aspects are limited in application by economics and in most cases still do not match grazing for welfare in temperate climates. Genomic technologies offer increased opportunities to breed for 'robustness' but like 'precision animal management systems' have still to be fully exploited. PMID:24360757

Logue, David N; Mayne, C Sinclair

2014-01-01

112

Progress in the use of computerised recording systems in dairy cow monitoring and extension in Malaysia.  

PubMed

The emphasis on cow records in Malaysian dairy extension programmes reflects the importance of herd fertility in the economics of dairying. Manual record keeping has not been able to make an impact on management due to difficulties experienced in quality control of the data and in analysing the data to produce useful information for farm managers. Computerised recording systems have been in use in Malaysia since 1985, both on government farms and in the small-holder dairy sector. The aim of both systems is firstly to improve farm efficiency by the provision of information to managers and extension workers and secondly to provide information for departmental planning purposes. The systems used in Malaysia are outlined, and the results over the first three years of operation are summarised. PMID:2371756

Pharo, H J; Sopian, M J; Kamaruddin, M; Abu Hassan, M A; Cheah, P F; Choo, T W

1990-05-01

113

Effect of lactation stage on the odd- and branched-chain milk fatty acids of dairy cattle under grazing and indoor conditions.  

PubMed

The pattern of odd- and branched-chain fatty acids (OBCFA) in milk fat reflects rumen microbial activity and proportions of different rumen microbial groups. Therefore, these milk fatty acids (FA) are used to predict rumen proportions of volatile fatty acids, duodenal flow of microbial protein, and occurrence of rumen acidosis. However, current models do not correct for the potential effects of lactation stage on the level of OBCFA in milk fat. Hence, the objectives of this study were 1) to describe progressive changes related to lactation stage in concentrations of milk FA, with emphasis on the OBCFA, using the incomplete gamma function of Wood, and 2) to analyze whether lactation curves of milk FA on the one hand and milk production or milk fat content on the other hand coincide through evaluation of the correlation between the parameters of the Wood functions fitted to individual animal data. Data were collected from 2 trials in which milk FA during lactation were monitored. The first experiment was a stable trial with 2 groups of 10 cows receiving 2 dietary treatments from wk 1 to 40 of lactation. The second experiment was a grazing trial with 9 cows that were followed during the first 18 wk of lactation. Lactation curves of milk production, milk fat content, and individual milk FA were developed using the incomplete gamma function of Wood for each of the 3 dietary strategies separately. For almost all of the milk FA, lactation curve shapes were similar for all 3 dietary treatments. The OBCFA with chain lengths of 14 and 15 carbon atoms followed the lactation curves of the short- and medium-chain milk FA, which increased in early lactation. The OBCFA with chain length of 17 carbon atoms decreased during the early lactation period, following the pattern of milk long-chain fatty acids. The short- and medium-chain milk FA and OBCFA in the early lactation period seemed to be negatively correlated with the starting milk production and milk fat content, but correlations were modest. Information of milk FA lactation curves should be incorporated in predictive and classification models based on these milk FA, to improve their performance. PMID:18565925

Craninx, M; Steen, A; Van Laar, H; Van Nespen, T; Martín-Tereso, J; De Baets, B; Fievez, V

2008-07-01

114

Short Communication: Comparison of Manual Versus Semiautomatic Milk Recording Systems in Dairy Goats  

Microsoft Academic Search

A total of 24 Murciano-Granadina dairy goats in early-midlactation were used to compare the labor time and data collection efficiency of using manual (M) vs. semiautomated (SA) systems for milk recording. Goats were milked once daily in a 2 × 12 parallel platform, with 6 milking units on each side. The M system used visual identification (ID) by large plastic

A. Ait-Saidi; G. Caja; S. Carne ´; A. A. K. Salama; J. J. Ghirardi

2008-01-01

115

Evaluation of protein fractionation systems used in formulating rations for dairy cattle  

Microsoft Academic Search

Production efficiency decreases when diets are not properly balanced for protein. Sensitivity analyses of the protein fractionation schemes used by the National Research Council Nutrient Requirement of Dairy Cattle (NRC) and the Cornell Net Carbohydrate and Protein System (CNCPS) were conducted to assess the influence of the uncertainty in feed inputs and the assumptions underlying the CNCPS scheme on metabolizable

Cristina Lanzas; S Seo; L O Tedeschi; D. G. Fox

2007-01-01

116

Overvagningssystem for Naeringsstoffer: Mejeriprodukter (Food Monitoring System for Nutrients: Dairy Products),  

National Technical Information Service (NTIS)

As a part of the food monitoring system for nutrients in the danish diet 160 samples of dairy products have been examined during 1985 at 3 of the 5 regional laboratories. The milk products homogenized milk with 3,5% fat, ymer and yogurt have been sampled ...

A. Wienberg T. Leth

1987-01-01

117

First Life Cycle Assessment of Milk Production from New Zealand Dairy Farm Systems  

Microsoft Academic Search

A first picture of the total environmental performance of milk production from a typical NZ dairy farm system, using Life Cycle Assessment (LCA) was produced and compare to European LCA studies. Five potential impacts have been assessed. Results were expressed per kg of milk produced at the farm gate and per ha of land use. In this first assessment, compared

Claudine Basset-Mens; Stewart Ledgard; Andrew Carran

118

Energy conservation and alternate energy resources for a dairy utilizing a water flush waste disposal system  

SciTech Connect

Electricity use and costs were evaluated for a dairy farm using a water flush disposal system. Electricity conservastion, reducing the peak electrical demand, and alternative energy production from animal waste can be reduce purchased electrical costs while still maintaining the benefits derived from mechanization. ref.

Erdman, M.D.; Bryan, W.L.; Johnson, J.C. Jr.; Newton, G.L.

1981-01-01

119

Membrane sequencing batch reactor system for the treatment of dairy industry wastewater  

Microsoft Academic Search

A membrane separation process was coupled to a sequencing batch reactor (SBR) for biological nutrient removal (BNR) processes and a combined system was named a membrane sequencing batch reactor (MSBR). MSBR was used for the treatment of dairy industry wastewater and optimized to increase the treatment efficiency. Since a diffuser-attached module design, subcritical flux operation, and intermittent suction method were

Tae-Hyun Bae; Sung-Soo Han; Tae-Moon Tak

2003-01-01

120

Production level, feed conversion efficiency, and nitrogen use efficiency of dairy production systems in China.  

PubMed

A study was conducted in China to evaluate the feed conversion efficiency, nitrogen use efficiency, and the amount of human-edible grains fed under different dairy systems. Three dairy systems were defined and studied: (i) smallholder subsistence farms (SH), (ii) peri-urban farms (PR), and iii) cooperative farms (CO). The PR system had the highest milk yield, better feed conversion efficiency, better nitrogen use efficiency, and used lower proportion of grains in the diet. Within a system, different farms had wide variations in feed conversion efficiency and nitrogen use efficiency, suggesting the need to improve management practices within the system. Among the three systems, SH and CO systems require the most improvements in the management practices. PMID:24510199

Wang, Chong; Liu, Jian-Xin; Makkar, Harinder Paul Singh; Wei, Ning-bo; Xu, Qun-mei

2014-04-01

121

77 FR 8717 - Dairy Product Mandatory Reporting  

Federal Register 2010, 2011, 2012, 2013

...Small businesses in the dairy product manufacturing \\1\\ industry have been defined by...there were 1,583 dairy manufacturing establishments...1\\ North American Industry Classification System...The dairy manufacturing...

2012-02-15

122

76 FR 34004 - Dairy Product Mandatory Reporting  

Federal Register 2010, 2011, 2012, 2013

...Small businesses in the dairy product manufacturing \\1\\ industry have been defined by...there were 1,583 dairy manufacturing establishments...1\\ North American Industry Classification System...The dairy manufacturing...

2011-06-10

123

The problem of grazing planning in a non-equilibrated environment, from the analytical procedure toward the system approach  

Microsoft Academic Search

The concept of grazing in general and goat grazing in particular, as the cause of the deterioration of ecosystems in all conditions, has profound roots in society and in the scientific community, mainly ecologists and environmentalists. Many authors have considered goats as destructive animals by nature, and grazing by these animals is considered one of the main reasons for desertification,

J. Mata; L. A. Bermejo; L. de Nascimento; A. Camacho

2010-01-01

124

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

PubMed

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 be restricted to well managed herds that already achieve acceptable herd fertility performance. PMID:24679704

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

2014-05-01

125

Study of fuel cell co-generation systems applied to a dairy industry  

Microsoft Academic Search

This paper presents a methodology for the study of a molten carbonate fuel cell co-generation system. This system is applied to a dairy industry of medium size that typically demands 2100kW of electricity, 8500kg\\/h of saturated steam (P=1.08MPa) and 2725kW of cold water production. Depending on the associated recuperation equipment, the co-generation system permits the recovery of waste heat, which

Elisângela M. Leal; José Luz Silveira

2002-01-01

126

Exploring the anthelmintic properties of Australian native shrubs with respect to their potential role in livestock grazing systems.  

PubMed

We measured in vitro anthelmintic activity in extracts from 85 species of Australian native shrub, with a view to identifying species able to provide a degree of worm control in grazing systems. Approximately 40% of the species showed significant activity in inhibiting development of Haemonchus contortus larvae. The most active extracts showed IC50 values of 60-300 microg/ml. Pre-incubation with polyvinylpolypyrrolidine removed the activity from some extracts, implicating tannins as the bioactive agent, while in other cases the pre-incubation had no effect, indicating the presence of other anthelmintic compounds. Plant reproductive maturity (onset of flowering or fruiting) was associated with increasing anthelmintic activity in some species. Variability was observed between plants of the same species growing in different environments, while variation between individual plants of the same species within a single field suggests the existence of distinct chemotypes. Significant activity against adult H. contortus worms in vitro was also demonstrated in a limited number of extracts tested against this life stage. Our study indicates that there is potential for Australian native shrubs to play an anthelmintic role in grazing systems, and highlights some plant biology factors which will need to be considered in order to maximize any anthelmintic effects. PMID:19523255

Kotze, A C; O'Grady, J; Emms, J; Toovey, A F; Hughes, S; Jessop, P; Bennell, M; Vercoe, P E; Revell, D K

2009-08-01

127

Greenhouse Gases and Ammonia Emissions from Organic Mixed Crop-Dairy Systems: A Critical Review of Mitigation Options  

Microsoft Academic Search

\\u000a Dairy production systems represent a significant source of air pollutants such as greenhouse gases (GHG), that increase global\\u000a warming, and ammonia (NH3), that leads to eutrophication and acidification of natural ecosystems. Greenhouse gases and ammonia are emitted both by\\u000a conventional and organic dairy systems. Several studies have already been conducted to design practices that reduce greenhouse\\u000a gas and ammonia emissions

S. M. Novak; J. L. Fiorelli

128

Dairy cows welfare quality in tie-stall housing system with or without access to exercise  

PubMed Central

Background Tie-stall housing of dairy cows is used extensively worldwide, despite of the welfare concerns regarding the restriction of voluntary movement and limitation of expression of the cows’ natural behaviour. The aim of this study was to compare the welfare quality of dairy cows kept in two types of tie-stall housing systems: with regular outdoor exercise and without access to exercise. In addition, the study investigated the relationship between different welfare measures of dairy cows kept in tie-stalls. Methods 3,192 lactating cows were assessed using the Welfare Quality® assessment protocol for cattle in 80 commercial dairy farms, half of the farms providing outdoor access for the animals to exercise. The descriptive statistical indicators were determined for the assessed measures and for the welfare criteria and principle scores. The data obtained in the two housing types were compared and the correlation coefficients were calculated between the different welfare measures. Results The significant differences found between the two housing systems for the majority of the animal based measures indicate the positive effect of exercise on the welfare of tethered cows. Many of the animal welfare parameters correlated with each other. For the farms allowing the cows’ turnout in a paddock, pasture or both, the mean scores for the welfare criteria and principles were higher than for the farms with permanent tethering of the cows, except the criteria absence of prolonged hunger and expression of social behaviours. The lowest scores were obtained for the criterion positive emotional state, in both housing systems. With regard to the overall classification, none of the farms were considered excellent. In the not classified category were only farms with all-year-round tethering of the animals and in the enhanced category only farms where the cows had outdoor access. Conclusions The welfare quality of the investigated dairy cows was significantly better in the tie-stall farms which allow exercise for cows (paddocks, pasture or both) than in those which do not. In the light of our results we consider that dairy cattle welfare is not necessarily poor in tie-stall housing systems, its quality depending on the management practices.

2013-01-01

129

A model of nitrogen efficiency in contrasting grass-based dairy systems.  

PubMed

Nitrogen (N) efficiency is one of the key drivers of environmentally and economically sustainable agricultural production systems. An N balance model was developed, evaluated, and validated to assess N use efficiency and N surplus and to predict N losses from contrasting grass-based dairy production systems in Ireland. Data from a 5-yr study were used to evaluate and validate the model. Grass-based and high-concentrate production systems combined with 3 divergent strains of Holstein-Friesian (HF) dairy cows-high-production North American (HP), high-durability North American (HD), and New Zealand (NZ)-were evaluated. As concentrate input increased, N surplus per hectare increased and N use efficiency per hectare decreased (23 and 10%, respectively). When the N required to rear replacement animals to maintain the production system was considered, the N surplus of the HP genetic strain was greater (156 kg of N/cow) than that of the HD (140 kg of N/cow) or the NZ (128 kg of N/cow). The model estimated N leaching of 8.1mg of NO(3)-N/L, similar to that measured by others at the same site. The model creates awareness of methods and indicators available to assess the most suitable and environmentally sustainable grass based dairy production systems. PMID:21257073

Ryan, W; Hennessy, D; Murphy, J J; Boland, T M; Shalloo, L

2011-02-01

130

The prevalence of serum antibodies to tick-borne infections in Mbale District, Uganda: The effect of agro-ecological zone, grazing management and age of cattle  

PubMed Central

Between August and October 2000, a cross-sectional study was conducted in smallholder dairy farms in Mbale District, Uganda to assess the prevalence of ticks and tick-borne diseases under different grazing systems and agro-ecological zones and understand the circumstances under which farmers operated. A questionnaire was administered to obtain information on dairy farm circumstances and practices. A total of 102 farms were visited and sera and ticks were collected from 478 animals. Sero-prevalence of tick-borne diseases was determined using an enzyme-linked immunoassay. Acaricides were used indiscriminately but the intensity of their use varied with the grazing system and zone. Cattle from different farms mixed for various reasons. During the dry seasons farmers have to get additional fodder from outside their farms that can result in importation of ticks. The prevalence of ticks and serum antibodies to tick-borne infections differed across the grazing systems and zones. The highest serum antibody prevalence (>60%) was recorded in the lowland zone under the free range and tethering grazing systems. The lowest tick challenge and serum antibody levels (<50%) were recorded in the midland and upland zones under a zero-grazing system. These findings suggest that endemic stability to East Coast Fever, babesiosis and anaplasmosis is most likely to have existed in the lowland zone, particularly, under the tethering and free-range grazing systems. Also, endemic stability for babesiosis existed in the upland zones. Endemic instability for East Coast Fever existed in the midland and upland zones. These structured observational studies are instrumental in planning of control strategies for ticks and tick borne diseases since production systems and the cattle population at high risk of the diseases in the district have been identified. Abbreviation: zone agro-ecological zone

Rubaire-Akiiki, C.; Okello-Onen, J.; Nasinyama, G.W.; Vaarst, M.; Kabagambe, E. K.; Mwayi, W.; Musunga, D.; Wandukwa, W.

2004-01-01

131

Intensive dairy systems: health implications of confined housing and the influence of stress management on welfare  

Microsoft Academic Search

Regula et al. (2004) studied the effect of confinement on dairy cows kept in three intensive husbandry systems: tie stalls with regular exercise during summer but not during winter; tie stalls with regular exercise year-round; and loose-housing with regular outdoor access. The study showed that loose-housing and regular exercise throughout the year had a positive effect on lameness, teat injuries,

Sara Biasutti

132

Dairy Wastes.  

ERIC Educational Resources Information Center

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)

Pico, Richard F.

1978-01-01

133

Lifetime productivity of dairy cows in smallholder farming systems of the Central highlands of Kenya.  

PubMed

Evaluation of lifetime productivity is sensible to target interventions for improving productivity of smallholder dairy systems in the highlands of East Africa, because cows are normally not disposed of based on productive reasons. Feeding strategies and involuntary culling may have long-term effects on productive (and therefore economic) performance of dairy systems. Because of the temporal scale needed to evaluate lifetime productivity, experimentation with feedstuffs in single lactations is not enough to assess improvements in productivity. A dynamic modelling approach was used to explore the effect of feeding strategies on the lifetime productivity of dairy cattle. We used LIVSIM (LIVestock SIMulator), an individual-based, dynamic model in which performance depends on genetic potential of the breed and feeding. We tested the model for the highlands of Central Kenya, and simulated individual animals throughout their lifetime using scenarios with different diets based on common feedstuffs used in these systems (Napier grass, maize stover and dairy concentrates), with and without imposing random mortality on different age classes. The simulations showed that it is possible to maximise lifetime productivity by supplementing concentrates to meet the nutrient requirements of cattle during lactation, and during early development to reduce age at first calving and extend productive life. Avoiding undernutrition during the dry period by supplementing the diet with 0.5 kg of concentrates per day helped to increase productivity and productive life, but in practice farmers may not perceive the immediate economic benefits because the results of this practice are manifested through a cumulative, long-term effect. Survival analyses indicated that unsupplemented diets prolong calving intervals and therefore, reduce lifetime productivity. The simulations with imposed random mortality showed a reduction of 43% to 65% in all productivity indicators. Milk production may be increased on average by 1400 kg per lactation by supplementing the diet with 5 kg of concentrates during early lactation and 1 kg during late lactation, although the optimal supplementation may change according to milk and concentrate prices. Reducing involuntary culling must be included as a key goal when designing interventions to improve productivity and sustainability of smallholder dairy systems, because increasing lifetime productivity may have a larger impact on smallholders' income than interventions targeted to only improving daily milk yields through feeding strategies. PMID:22444823

Rufino, M C; Herrero, M; Van Wijk, M T; Hemerik, L; De Ridder, N; Giller, K E

2009-07-01

134

Interactive computer simulation of dairy farm systems as a method for making energy management decisions  

SciTech Connect

To facilitate management decisions an analytical model was developed to predict energy and labor requirements and costs for milking and feed handling systems. The Dairy Farm Simulation Model was based on detailed time and motion studies, and energy audits of 21 dairy farms in Michigan. Data included labor hours and energy consumption per month for each operation required for milking and feed handling and charges based on Detroit Edison electrical rate schedules. The result of optimizing the electrical rate charges for simulated milking systems is indicated by the Time-of-Day Rate Schedule which provides the lowest cost to farm operators willing to adjust milking times. Simulation of mobile and stationary feeding systems for six herd sizes includes calculations of capital investment and operating costs in addition to labor and energy cost. Results indicate that mobile systems required a lower investment cost while stationary systems realize lower energy costs. Labor requirements per cow decreased as herd size increased for mobile systems, but remained the same for stationary systems regardless of herd size. The energy required to operate each system, based on the number of oil barrel equivalents, indicates the stationary system required less energy for herd sizes up to and including 150 cows, while mobile systems indicate a lower energy requirement for herd sizes greater than 150 cows. In general, no single system emerged as the best, rather it depended on the operator's personal preference.

Hewett, E.J. III

1983-01-01

135

GRAZPLAN: Decision support systems for Australian grazing enterprises. III. Pasture growth and soil moisture submodels, and the GrassGro DSS  

Microsoft Academic Search

This paper specifies the pasture growth module of a model for simulating grazing systems for ruminants and the soil moisture budget that drives pasture growth. Both modules operate at a daily time step. The pasture growth module is quite general in structure but recognises four functional groups of pasture plants: annual and perennial species are distinguished, as are grasses and

A. D. Moore; J. R. Donnelly; M. Freer

1997-01-01

136

The growth of young cattle and sheep managed on a preference and follower herd basis within a rotational grazing system on veld  

Microsoft Academic Search

The trial was carried out at the Kokstad Research Station in the summer rainfall area on the Eastern sea board of South Africa. Growing cattle and sheep in the first season and cattle only in the second were run on a preference and follower herd basis within a rotational grazing system on veld. This resulted in better mass gains in

A. D. Lyle; G. M. Brockett; S. F. Lesch

1982-01-01

137

A longitudinal study of disease incidence and case-fatality risks on small-holder dairy farms in coastal Kenya.  

PubMed

A longitudinal study was carried out in the coastal lowlands coconut-cassava agro-ecological zone of Kaloleni Division, Coast Province, Kenya between June 1990 and December 1991 to estimate disease incidence and cause-specific case-fatality risk in an average of 120 cattle in 26 small-holder dairy herds kept in two grazing-management systems. East Coast fever (ECF) was the predominant disease diagnosed; the mean monthly incidence rate was 2.5 and 6.9% in animals < or = 18 months of age under stall-fed and herded-grazing systems, respectively. In cattle > 18 months of age, the monthly incidence rate was < 1%. The 6-month ECF incidence rate was 20+/-8% (S.E.) in the stall-feeding system compared with 39+/-7% in the herded-grazing systems. There was a gradual increase in antibody prevalence with age to over 90% in cattle over 18 months of age in herded-grazing systems, whilst less than a third of cattle in the stall-feeding systems were sero-positive at any age. Overall accumulated mortality to 18 months of age was estimated to be 56%. Annual mortality in cattle > 18 months averaged 9%. Cattle managed in the herded-grazing system had a 60% higher mortality, although not significantly so, than those fed in stalls. Deaths due to ECF accounted for over two-thirds of the deaths. ECF was then the major disease constraint to small-holder dairy production in the coconut zone of coastal Kenya. Clinical cases occur the whole year round (especially in young stock)--despite apparent tick control, and in both herded-grazing and stall-feeding system. PMID:11566375

Maloo, S H; Rowlands, G J; Thorpe, W; Gettinby, G; Perry, B D

2001-11-01

138

Test and analysis of a solar dairy water heating system  

SciTech Connect

The performance of a combined solar collection and refrigeration heat recovery system for preheating wash water was monitored over a two month period. A system model was developed to predict year long system performance in various operating modes.

Valdivia, H.; Fortis, T.; Rumsey, T.R.

1982-12-01

139

Implementation and use of a microcomputer-based management information system to monitor dairy herd performance  

PubMed Central

A microcomputer-based herd management information system was implemented as part of the herd health program provided to 13 dairy clients by the Ontario Veterinary College, University of Guelph. The study was conducted over a two year period. Data were collected from on-farm event diaries, veterinary visit reports, and production testing information. Selected indices of reproduction, udder health, production, and heifer performance were reported. It was concluded that the implementation of a microcomputer-based information management system, operated as a bureau service, was feasible. However, limitations to the implementation in veterinary practice were identified.

Lissemore, Kerry D.; Leslie, Ken E.; Menzies, Paula I.; Martin, S. Wayne; Meek, Alan H.; Etherington, Wayne G.

1992-01-01

140

Lameness scoring system for dairy cows using force plates and artificial intelligence.  

PubMed

Lameness scoring is a routine procedure in dairy industry to screen the herds for new cases of lameness. Subjective lameness scoring, which is the most popular lameness detection and screening method in dairy herds, has several limitations. They include low intra-observer and inter-observer agreement and the discrete nature of the scores which limits its usage in monitoring the lameness. The aim of this study is to develop an automated lameness scoring system comparable with conventional subjective lameness scoring by means of artificial neural networks. The system is composed of four balanced force plates installed in a hoof-trimming box. A group of 105 dairy cows was used for the study. Twenty-three features extracted from ground reaction force (GRF) data were used in a computer training process which was performed on 60 per cent of the data. The remaining 40 per cent of the data were used to test the trained system. Repeatability of the lameness scoring system was determined by GRF samples from 25 cows, captured at two different times from the same animals. The mean sd was 0.31 and the mean coefficient of variation was 14.55 per cent, which represents a high repeatability in comparison with subjective vision-based scoring methods. Although the highest sensitivity and specificity values were seen in locomotion score groups 1 and 4, the automatic lameness system was both sensitive and specific in all groups. The sensitivity and specificity were higher than 72 per cent in locomotion score groups 1 to 4, and it was 100 per cent specific and 50 per cent sensitive for group 5. PMID:22141114

Ghotoorlar, S Mokaram; Ghamsari, S Mehdi; Nowrouzian, I; Ghotoorlar, S Mokaram; Ghidary, S Shiry

2012-02-01

141

Five year-round forage systems in a dairy effluent sprayfield: phosphorus removal.  

PubMed

In northern Florida, forages are grown in dairy effluent sprayfields to recover excess P. Our purpose was to evaluate five year-round forage systems for their capacity to remove P from a dairy sprayfield. The soil is a Kershaw sand (thermic, uncoated Typic Quartzipsamment). Systems included bermudagrass (Cynodon spp.)-rye (Secale cereale L.) (BR), perennial peanut (Arachis glabrata Benth.)-rye (PR), corn (Zea mays L.)-forage sorghum [Sorghum bicolor (L.) Moench]-rye (CSR), corn-bermudagrass-rye (CBR), and corn-perennial peanut-rye (CPR). Forages were grown for five 12-mo cycles. Effluent P rates were 80, 120, and 165 kg ha-1 cycle-1. The 5-cycle P removal was 67 kg ha-1 cycle-1 for BR, 54 kg ha-1 for CBR, 52 kg for CSR, 45 kg for PR, and 43 for CPR. Removal of P by winter rye was low. There were differences in system rankings among cycles primarily due to changes in the performance of perennial forages. In the first two cycles, BR had the greatest P removal (91 kg ha-1 cycle-1) due to high bermudagrass yield and P concentration. In the first cycle, P removal was lowest for PR (36 kg ha-1) because perennial peanut was slow to establish. In later cycles, P removal for BR declined because bermudagrass yield and P concentration declined. It increased for PR because peanut yield increased. The yield of corn in CBR, CPR, and CSR was consistently high but P concentration was modest (avg. 2.2 g kg-1). Sorghum produced moderate but stable yield and had low P levels (avg. 1.8 g kg-1). Effluent rate marginally affected the performance of most grasses. For P recovery in dairy sprayfields in northern Florida, the best warm-season forage would likely be a high yielding, persistent bermudagrass. PMID:17215225

Woodard, Kenneth R; Sollenberger, Lynn E; Sweat, Lewin A; Graetz, Donald A; Rymph, Stuart J; Joo, Yongsung

2007-01-01

142

Grazing incidence relay optics  

NASA Technical Reports Server (NTRS)

The necessity to work in the focal plane of the primary mirrors has been one of the factors limiting the utility of grazing incidence telescopes in X-ray astronomy. In connection with the reported investigation, computer ray tracing programs have been used to study the performance of several grazing incidence relay optics (GIRO) systems used together with a large nested solar X-ray telescope. It was found that GIRO magnifiers are useful to map appropriate sized regions of the sun onto available CCD detectors. GIRO collimators can be used together with an X-ray spectrometer to study the X-ray spectrum from very small regions on the sun. Attention is given to the stationary mode, the tracking mode, and the size of GIRO elements. It is found that for a given GIRO size and magnification a use of the diverging system has the advantage of reducing the overall length of the main telescope-GIRO combination. However, the resolution provided by the diverging GIRO may not be as good as that obtained with the corresponding converging GIRO.

Chase, R. C.; Davis, J. M.; Krieger, A. S.; Underwood, J. H.

1982-01-01

143

Effect of fertility on the economics of pasture-based dairy systems.  

PubMed

There are significant costs associated with reproductive inefficiency in pasture-based dairy herds. This study has quantified the economic effect of a number of key variables associated with reproductive inefficiency in a dairy herd and related them to 6-week calving rate for both cows and heifers. These variables include: increased culling costs, the effects of sub optimum calving dates, increased labour costs and increased artificial insemination (AI) and intervention costs. The Moorepark Dairy Systems Model which is a stochastic budgetary simulation model was used to simulate the overall economic effect at farm level. The effect of change in each of the components was simulated in the model and the costs associated with each component was quantified. An analysis of national data across a 4-year period using the Irish Cattle Breeding Federation database was used to quantify the relationship between the 6-week calving rate of a herd with survivability (%), calving interval (days) and the level of AI usage. The costs associated with increased culling (%), calving date slippage (day), increased AI and intervention costs (0.1 additional inseminations), as well as, increased labour costs (10%) were quantified as €13.68, €3.86, €4.56 and €29.6/cow per year. There was a statistically significant association between the 6-week calving rate and survivability, calving interval and AI usage at farm level. A 1% change in 6-week calving rate was associated with €9.26/cow per annum for cows and €3.51/heifer per annum for heifers. This study does not include the indirect costs such as reduced potential for expansion, increased costs associated with failing to maintain a closed herd as well as the unrealised potential within the herd. PMID:24679449

Shalloo, L; Cromie, A; McHugh, N

2014-05-01

144

Energy Integrated Dairy Farm System in North Dakota  

Microsoft Academic Search

The EIFS project at North Dakota State University, located at Fargo, North Dakota, is an effort to show how a Northern Great Plains EIFS might be operated. This farm used a combination of energy conservation, energy capture, and energy production. Energy conservation was demonstrated using reduced tillage in a typical cropping system and by using heat reclamation equipment on the

G. Pratt; J. Lindley; H. Hirning; J. Giles

1986-01-01

145

The epidemiology of Theileria parva infections on smallholder dairy farms in Kenya.  

PubMed

The purpose of the study was to characterize the differences in epidemiology (risks of infection, morbidity, mortality) and potential control of East Coast fever (ECF) between the selected strata. Evidence of Theileria parva infection was assessed by increased antibody levels as measured in an indirect ELISA test by the percent positivity (PP) of serum samples relative to a strong positive reference serum. A prospective cohort study was conducted in five purposively sampled agroecological zone (AEZ)-grazing system strata in Murang'a District, Kenya, between March 1995 and June 1996. The study strata were selected to represent the widest range of ECF risks in the district and included, zero-grazing and open-grazing farms in the Upper Midlands (UM) one and four AEZs and zero-grazing farms in the UM2 AEZ. In total, 225 calves from 188 smallholder farms were examined from birth to age six months. Calves were recruited into the study at birth and visited within the first two weeks of life and thereafter at biweekly intervals for up to 14 visits. Important differences were observed between the different AEZ-grazing strata. Seroconversion risks of T. parva were highest in the UM4-open grazing stratum. Antibody prevalence in adult cattle and ECF morbidity and mortality risks were also highest in this stratum. In the open-grazing strata, particularly in the lower elevation AEZ, UM4, there was stronger challenge and a greater impact of ECF. There is likely to be an expansion of smallholder dairy farming into this area so that it is likely to be the most important target production system for ECF control in the central highlands of Kenya. PMID:11193631

Gitau, G K; McDermott, J J; Katende, J M; Perry, B D

2000-01-01

146

The impact of potential nitrous oxide mitigation strategies on the environmental and economic performance of dairy systems in four New Zealand catchments  

Microsoft Academic Search

The expansion of the New Zealand dairy industry has resulted in growing concern about the environmental impacts. As such, efforts are being made to design environmentally and economically sustainable management strategies. In this desktop study, the performance of two management strategies was assessed for dairy systems in four New Zealand catchments. Survey and monitoring information on farm management, farm production,

C. A. M. De Klein; R. M. Monaghan

2005-01-01

147

Evaluating mountain goat dairy systems for conversion to the organic model, using a multicriteria method.  

PubMed

Organic farming conserves natural resources, promotes biodiversity, guarantees animal welfare and obtains healthy products from raw materials through natural processes. In order to evaluate possibilities of increasing organic animal production, this study proposes a farm-scale multicriteria method for assessing the conversion of dairy goat systems to the organic model. In addition, a case study in the Northern Sierra of Seville, southern Spain, is analysed. A consensus of expert opinions and a field survey are used to validate a list of potential indicators and issues for assessing the conversion, which consider not only the European Community regulations for organic livestock farming, but also agroecological principles. As a result, the method includes 56 variables integrated in nine indicators: Nutritional management, Sustainable pasture management, Soil fertility and contamination, Weed and pest control, Disease prevention, Breeds and reproduction, Animal welfare, Food safety and Marketing and management. The nine indicators are finally integrated in a global index named OLPI (Organic Livestock Proximity Index). Application of the method to a case study with 24 goat farms reveals an OLPI value of 46.5% for dairy goat farms located in mountain areas of southern Spain. The aspects that differ most from the agroecological model include soil management, animal nutrition and product marketing. Results of the case study indicate that the proposed method is easy to implement and is useful for quantifying the approximation of conventional farms to an organic model. PMID:22436287

Mena, Y; Nahed, J; Ruiz, F A; Sánchez-Muñoz, J B; Ruiz-Rojas, J L; Castel, J M

2012-04-01

148

Seroprevalences of vector-transmitted infections of small-holder dairy cattle in coastal Kenya.  

PubMed

A cross-sectional study was carried out from July to September 1989 in Kaloleni Division, Coast Province, Kenya to estimate the prevalence of vector-transmitted diseases in small-holder dairy cattle and to identify the risk factors associated with different management systems. One hundred and thirty of the 157 herds with dairy cattle in Kaloleni Division were surveyed. These were from three agro-ecological zones (coconut-cassava, cashew nut-cassava and livestock-millet), comprised two management systems (stall-feeding and herded grazing) and were herds with either dairy cattle only or with Zebu and dairy cattle. A formal questionnaire sought answers to questions on cattle health and management practices. A total of 734 dairy and 205 Zebu cattle in 78 dairy and 52 mixed (dairy and Zebu) herds were sampled and screened for haemoparasites (Trypanosoma, Anaplasma, Babesia, and Theileria infections). Sera were tested for antibodies to Theileria parva, using the schizonts-antigen indirect fluorescent-antibody (IFA) test and to antibodies for Babesia bigemina and antigens to Anaplasma marginale by enzyme-linked immunosorbent assay (ELISA). Packed-cell volume (PCV) also was measured. Tick-control measures were practised by all except three of the farmers. Despite this, overall seroprevalence to T. parva was >70%--suggesting either that control practices were not strictly implemented or they were ineffective. The seroprevalence of T. parva in adult cattle kept in stall-feeding systems in the coconut-cassava zone was significantly lower (57+/-8% (S.E.)) than in herded-grazing systems (79+/-3%) and there was no association between antibody prevalence and age of cattle in this zone. Antibody prevalences in cattle in the cashew nut-cassava and the drier livestock-millet zone increased with age. Cattle in herded-grazing systems had an overall lower seroprevalence of T. parva infection in the livestock-millet zone (45+/-6%) than in the other two zones. Analysis was confined to the coconut-cassava zone for B. bigemina and to the coconut-cassava and cashew nut-cassava zones for A. marginale. Mean prevalences of B. bigemina were 40.9+/-9 and 73+/-6% for dairy cattle under stall-feeding and herded-grazing systems, respectively, and increased with age. Antigen prevalences of A. marginale were over 80% in all age groups of cattle in the coconut-cassava and cashew nut-cassava zones. Overall trypanosome prevalence in cattle was <1%. Trypanocidal treatment was uncommon. The variations in antibody prevalence associated with risk factors such as feeding system, agro-ecological zone and age of animal suggest that management system influenced exposure to tick-borne infection (particularly, T. parva infections) in small-holder dairy cattle in coastal Kenya. PMID:11566374

Maloo, S H; Thorpe, W; Kioo, G; Ngumi, P; Rowlands, G J; Perry, B D

2001-11-01

149

Engineering an Innovative Bioreactor with Existing Lagoon System for Dairy Wastewater Treatment\\/Reuse - A Pilot Plant Study  

Microsoft Academic Search

One of a large dairy farm (60 acres of land with 1,600 livestock) located on the island of Oahu, Hawaii is investigated for potential integration of the existing lagoon system with cost effective pretreatment unit process. Based on the laboratory study, a pilot plant has been installed two 10 m3 of anaerobic bioreactor. Two layers of media \\

Eulsaeng Cho; P. Y. Yang

150

Effects of manure treatment and soil compaction on plant production of a dairy farm system converting to organic farming practice  

Microsoft Academic Search

In a dairy farm system during conversion from conventional to organic farming practice, the effects of different cattle manure treatment methods, fertilisation level and soil compaction were studied over a period of 6 years. Yields, botanical composition, earthworm quantity and soil porosity were monitored. The manure was treated as diluted, aerated and mechanically separated slurry (solid compost on tilled land

Sissel Hansen

1996-01-01

151

Waste Dairy Product-Disposal-McMurdo  

NSF Publications Database

... dairy product (ice cream) through the McMurdo sewer system. The waste dairy product ingredients are ... the product has not degraded enough to produce odors which may be associated with sour milk products ...

152

The Bioeconomic Potential for Agroforestry in Australia’s Northern Grazing Systems  

Microsoft Academic Search

Although agriculture generates 16% of Australia’s greenhouse gas emissions, it also has the potential to sequester large quantities\\u000a of emissions through land use management options such as agroforestry. Whilst there is an extensive amount of agroforestry\\u000a literature, little has been written on the economic consequences of adopting silvopastoral systems in northern Australia.\\u000a This paper reports the financial viability of adopting

Peter Donaghy; Steven Bray; Rebecca Gowen; John Rolfe; Michael Stephens; Madonna Hoffmann; Anne Stunzer

2010-01-01

153

Modelling Integrated Dairy Systems In The UK: Towards Economic and Environmental Sustainability  

Microsoft Academic Search

This paper draws on the results of a multi-disciplinary research project funded by Defra1 which has focussed on identifying and developing practical approaches by which the dairy sector can reduce inputs and diffuse pollution, whilst maintaining biodiversity, product quality, high animal health and welfare standards and market competitiveness. The pressures on UK dairying for change towards greater economic and environmental

Allan J. Butler; Martin M. Turner

2007-01-01

154

Effect of biological control through the daily application of spores of Duddingtonia flagrans in lambs kept under an evasive grazing system in the Netherlands.  

PubMed

In 2004, an experiment was carried out to evaluate the effect of biological control through feeding spores of Duddingtonia flagrans on parasitic gastroenteritis in lambs, kept under an evasive grazing system. In total 66 lambs were used. Forty naturally infected 3-month old ram lambs were weaned in mid June, and divided into four groups of 10 lambs. On 21 June, G1-G4 were moved to four separate virtually clean plots, they were moved after 4 and 8 weeks to similar plots, and housed after 12 weeks to be necropsied 16 days later. The other 26 lambs had been raised helminth-free, and were used as pairs of tracer lambs. All but one of these pairs, were grazed during the last 2 weeks on each plot. The remaining pair (TA) was grazed during the last 2 weeks on pasture (30 August to 13 September) on the plot that had been grazed by G3 between 19 July and 16 August, to study inhibited development in Haemonchus contortus. All lambs were fed 200 g of concentrates daily throughout the whole period, and those of G1 and G2 were also fed 500,000 spores of D. flagrans/kg bodyweight daily. The faecal cultures demonstrated a high reduction in yield as a result of fungal application. However, no differences between groups were seen in weight gain, faecal egg counts, pasture larval counts, worm counts and tracer worm counts. H. contortus was the dominant species, and it is obvious that the moves at 4-week intervals prevented the development of severe haemonchosis. This is in particular demonstrated by the much higher worm counts in the two TA tracer lambs grazed. Nevertheless, increases to high faecal egg counts 3 weeks after the first and second moves, indicated acquisition of infection before these moves and at least subclinical haemonchosis. This was supported with the worm counts of lambs and tracer lambs. A higher proportion of inhibited early L4 than in other tracers and than in the permanent lambs were found in the pair of TA tracer lambs. This indicates that moves to new pastures in late summer and autumn delays the onset of inhibition. PMID:16713679

Eysker, M; Bakker, N; Kooyman, F N J; Olthuis, S Olde; Ploeger, H W

2006-09-10

155

Hock lesion epidemiology in cubicle housed dairy cows across two breeds, farming systems and countries.  

PubMed

This cross-sectional study examined various aspects of cubicle design and management in terms of their potential as risk factors for hock lesions, using an epidemiological approach. Cubicle dairy farms in Germany and Austria with Holstein Friesian or Simmental cows were visited during the winter housing season. 105 farms and 3691 cows were included in the analysis which consisted of three steps: bifactorial regression, regression trees and multiple linear regression. The mean farm prevalence of hock lesions, i.e. scabs, wounds, and swellings was 50%, with a range from 0 to 100%. The final model contained eight factors which were largely related to lying comfort and explained 75% of the variance. The presence of a curb turned out to be the most influential beneficial factor. Additionally, there were fewer hock lesions when cows were housed with deep bedded cubicles compared to cubicles without deep bedding. Other factors in the regression model were softness and length of the lying surface and height of free space under cubicle partitions, the proportion of overconditioned cows and a variable encoding three different combinations of region, husbandry system (organic and conventional) and breed. Independently from the risk factor model hock lesions were positively correlated with lameness at herd level as well as at animal level. This probably results from related risk factors for both conditions. It can be concluded that lying comfort of dairy cows should be improved in order to prevent hock lesions. In addition, preventive measures for hock lesions at the same time have a potential of reducing lameness and thus to improve cow welfare in several aspects. PMID:23174217

Brenninkmeyer, Christine; Dippel, Sabine; Brinkmann, Jan; March, Solveig; Winckler, Christoph; Knierim, Ute

2013-05-01

156

The effect of improving cow productivity, fertility, and longevity on the global warming potential of dairy systems  

Microsoft Academic Search

This study compared the environmental impact of a range of dairy production systems in terms of their global warming potential (GWP, expressed as carbon dioxide equivalents, CO2-eq.) and associated land use, and explored the efficacy of reducing said impact. Models were developed using the unique data generated from a long-term genetic line × feeding system experiment. Holstein-Friesian cows were selected

M. J. Bell; E. Wall; G. Russell; G. Simm; A. W. Stott

2011-01-01

157

Constraint analysis to improve integrated dairy production systems in developing countries: the importance of participatory rural appraisal.  

PubMed

The paper describes the rationale and importance of the approaches and methodologies of Participatory Rural Appraisal (PRA) to enable constraint analysis, to understand the complexities of farming systems and to improve integrated dairy productivity. Implicit in this objective is Farming Systems Research (FSR), which focused on cropping systems in the 1970's, with the subsequent addition of animal components. The methodology for FSR involves the following sequential components: site selection, site description and characterization (diagnosis), planning of on-farm research, on-farm testing and validation of alternatives, diffusion of results, and impact assessment. PRA is the development of FSR, which involves the active participation of farmers to identify constraints and plan appropriate solutions. In the Coordinated Research Project (CRP), the approach was adapted to 10 different country situations and led to Economic Opportunity Surveys (EOS) and Diagnostic Surveillance Studies (DSS), allowing the planning and implantation of integrated interventions to improve dairy productivity. PMID:18265864

Devendra, C

2007-12-01

158

Study of fuel cell co-generation systems applied to a dairy industry  

NASA Astrophysics Data System (ADS)

This paper presents a methodology for the study of a molten carbonate fuel cell co-generation system. This system is applied to a dairy industry of medium size that typically demands 2100 kW of electricity, 8500 kg/h of saturated steam ( P=1.08 MPa) and 2725 kW of cold water production. Depending on the associated recuperation equipment, the co-generation system permits the recovery of waste heat, which can be used for the production of steam, hot and cold water, hot and cold air. In this study, a comparison is made between two configurations of fuel cell co-generation systems (FCCS). The plant performance has been evaluated on the basis of fuel utilisation efficiency and each system component evaluated on the basis of second law efficiency. The energy analysis presented shows a fuel utilisation efficiency of about 87% and exergy analysis shows that the irreversibilities in the combustion chamber of the plant are significant. Further, the payback period estimated for the fuel cell investment between US 1000 and US 1500/kW is about 3 and 6 years, respectively.

Leal, Elisângela M.; Silveira, José Luz

159

Methane emissions measured directly from grazing livestock in New Zealand  

NASA Astrophysics Data System (ADS)

We report measurements of methane emissions from individual ruminant livestock-both sheep and dairy cows-grazing pasture typical of New Zealand lowlands in the temperate southwest Pacific. These are the first measurements reported from grazing sheep, and among the first from grazing cattle. The measurement technique, developed at Washington State University, enables emission rates to be determined from analyses of "breath" samples collected while grazing. More than 250 measurements of daily methane emission from 50 sheep (8 months old) were made, with flock-mean emission 18.9 ± 0.8 g hd -1 d -1. Although emissions were weakly correlated with feed intake, they represented a 4.6 ± 0.1 % average loss of gross dietary energy. The corresponding mean emission based on 40 measurements of daily emissions from 10 lactating dairy cows was 263 ± 10 g hd -1 d -1, approximately 6.2% of estimated gross energy intake. A notable feature was the large inter-sheep variability in daily methane emission (factor of 1.4 range) that could not be attributed to variable intake. This would appear to suggest an appreciable diversity of methanogenetic response to digestion, and may be significant in the search for strategies to control emissions of this greenhouse gas.

Lassey, Keith R.; Ulyatt, Marcus J.; Martin, Ross J.; Walker, Carolyn F.; David Shelton, I.

160

Nutritional management to optimize fertility of dairy cows in pasture-based systems.  

PubMed

The efficiency of milk production in pasture-based systems is heavily influenced by calving pattern, necessitating excellent reproductive performance in a short-breeding season. Where grazed pasture is the major component of the diet, cows are underfed relative to their intake potential. The cow responds by reducing milk output, but fertility is generally better than high intake confinement systems that achieve greater milk production per cow. A number of studies have identified body condition score (BCS) measurements that are related to likelihood of both submission and conception. Blood metabolites and metabolic hormones linked to fertility outcomes are now well characterized. In general, fertility variables have favourable associations with circulating concentrations of glucose, insulin and IGF-1 and unfavourable associations with non-esterified fatty acids, ?-hydroxybutyrate and endogenous growth hormone. Nutritional strategies to impact these metabolic indicators have been utilized, but effects on herd fertility are inconsistent. Simply supplementing cows with additional energy in the form of standard concentrates does not appear to have a pronounced effect on fertility. Energy from additional concentrates fed during lactation is preferentially partitioned towards extra milk production rather than BCS repletion. The higher the genetic merit for milk production, the greater the partitioning of additional nutrients to the mammary gland. This review outlines the unique nutritional challenges of pasture-based systems, the role of specific metabolic hormones and metabolites in regulating reproductive function, and nutritional strategies to improve herd fertility. PMID:24844127

Butler, S T

2014-05-01

161

Epidemiology of Fasciola gigantica and amphistomes in cattle on traditional, small-scale dairy and large-scale dairy farms in the southern highlands of Tanzania.  

PubMed

A longitudinal descriptive study was conducted to determine the prevalence and distribution of flukes (Fasciola gigantica and amphistomes) on traditional, large-scale and small-scale dairy cattle farms in Iringa district, southern highlands of Tanzania. Coprological examinations of different cohorts for the presence of fluke eggs were recorded monthly. Results indicated a significant influence of the type of management on the prevalence of both Fasciola and amphistomes. The prevalence of flukes was highest in the traditional system, moderate in the large-scale dairy system and lowest in the small-scale dairy system in most parts of the year. Adults and yearlings had the highest prevalence of flukes in all management systems throughout the year. The proportion of animals excreting amphistome eggs was always higher than that of animals excreting Fasciola eggs in all zones, villages, management systems, farms and age groups. The proportion of animals passing fluke eggs increased gradually from the early dry season and peaked at the end of the dry season and the early part of the rainy season. Strategic treatments against flukes are recommended in adults and yearlings only in traditional and large-scale dairy farms. Routine treatments of calves/weanlings in large-scale and traditional farms and zero-grazed small-scale dairy cattle farms might be unnecessary. For a cost-effective helminth control programme in the area, strategic treatments at the beginning of the dry season (June) and at the end of the dry/early rainy season (November/December) are recommended. PMID:15934638

Keyyu, J D; Monrad, J; Kyvsgaard, N C; Kassuku, A A

2005-05-01

162

Nitrogen removal and nitrate leaching for two perennial, sod-based forage systems receiving dairy effluent.  

PubMed

In northern Florida, year-round forage systems are used in dairy effluent sprayfields to reduce nitrate leaching. Our purpose was to quantify forage N removal and monitor nitrate N (NO3(-)-N) concentration below the rooting zone for two perennial, sod-based, triple-cropping systems over four 12-mo cycles (1996-2000). The soil is an excessively drained Kershaw sand (thermic, uncoated Typic Quartzip-samment). Effluent N rates were 500, 690, and 910 kg ha(-1) per cycle. Differences in N removal between a corn (Zea mays L.)-bermudagrass (Cynodon spp.)-rye (Secale cereale L.) system (CBR) and corn-perennial peanut (Arachis glabrata Benth.)-rye system (CPR) were primarily related to the performance of the perennial forages. Nitrogen removal of corn (125-170 kg ha(-1)) and rye (62-90 kg ha(-1)) was relatively stable between systems and among cycles. The greatest N removal was measured for CBR in the first cycle (408 kg ha(-1)), with the bermudagrass removing an average of 191 kg N ha(-1). In later cycles, N removal for bermudagrass declined because dry matter (DM) yield declined. Yield and N removal of perennial peanut increased over the four cycles. Nitrate N concentrations below the rooting zone were lower for CBR than CPR in the first two cycles, but differences were inconsistent in the latter two. The CBR system maintained low NO3(-)-N leaching in the first cycle when the bermudagrass was the most productive; however, it was not a sustainable system for long-term prevention of NO3(-)-N leaching due to declining bermudagrass yield in subsequent cycles. For CPR, effluent N rates > or = 500 kg ha(-1) yr(-1) have the potential to negatively affect ground water quality. PMID:12809300

Woodard, Kenneth R; French, Edwin C; Sweat, Lewin A; Graetz, Donald A; Sollenberger, Lynn E; Macoon, Bisoondat; Portier, Kenneth M; Rymph, Stuart J; Wade, Brett L; Prine, Gordon M; Van Horn, Harold H

2003-01-01

163

Dairy wastewater treatment using an activated sludge-microalgae system at different light intensities.  

PubMed

A microalgae-bacteria system was used for dairy industry wastewater treatment in sequenced batch mode in a photobioreactor. The research investigated the influence of two light intensities: 360 and 820 ?mol m(-2)s(-1) on treatment performances, microalgal cell recovery and dynamics of the protozoan community. Results showed that the light intensity of 360 ?mol m(-2)s(-1) was found to be insufficient to support photosynthetic activity after the increase of bacterial biomass leading to the decrease of organic matter and ammonium removal efficiencies from 95 to 78% and 95 to 41%, respectively. Maximum microalgal cells recovery was about 63%. Continuous modification in the protozoan community was also noticed during this test. Increasing the light intensity to 820 ?mol m(-2)s(-1) led to better microalgal cells recovery (up to 88%) and improved treatment performances. However, the decrease of protozoan richness to small flagellates and free-swimming ciliates was noticed. Moreover, the developed protozoan trophic network was found to be different from that identified in the conventional activated sludge system. The study emphasized that high increase of bacterial biomass promoted in nutrient- and organic matter-rich wastewater can strongly affect the treatment performances as a result of the shadow effect produced on the photoautotrophic microalgae aggregates. PMID:24759517

Tricolici, O; Bumbac, C; Patroescu, V; Postolache, C

2014-01-01

164

Hyperketonemia during lipopolysaccharide-induced mastitis affects systemic and local intramammary metabolism in dairy cows.  

PubMed

Hyperketonemia interferes with the metabolic regulation in dairy cows. It is assumed that metabolic and endocrine changes during hyperketonemia also affect metabolic adaptations during inflammatory processes. We therefore studied systemic and local intramammary effects of elevated plasma ?-hydroxybutyrate (BHBA) before and during the response to an intramammary lipopolysaccharide (LPS) challenge. Thirteen dairy cows received intravenously either a Na-dl-?-OH-butyrate infusion (n=5) to achieve a constant plasma BHBA concentration (1.7±0.1mmol/L), with adjustments of the infusion rates made based on immediate measurements of plasma BHBA every 15min, or an infusion with a 0.9% NaCl solution (control; n=8) for 56h. Infusions started at 0900h on d 1 and continued until 1700h 2 d later. Two udder quarters were challenged with 200?g of Escherichia coli LPS and 2 udder quarters were treated with 0.9% saline solution as control quarters at 48h after the start of infusion. Blood samples were taken at 1 wk and 2h before the start of infusions as reference samples and hourly during the infusion. Mammary gland biopsies were taken 1 wk before, and 48 and 56h (8h after LPS challenge) after the start of infusions. The mRNA abundance of key factors related to BHBA and fatty acid metabolism, and glucose transporters was determined in mammary tissue biopsies. Blood samples were analyzed for plasma glucose, BHBA, nonesterified fatty acid, urea, insulin, glucagon, and cortisol concentrations. Differences were not different for effects of BHBA infusion on the mRNA abundance of any of the measured target genes in the mammary gland before LPS challenge. Intramammary LPS challenge increased plasma glucose, cortisol, glucagon, and insulin concentrations in both groups but increases in plasma glucose and glucagon concentration were less pronounced in the Na-dl-?-OH-butyrate infusion group than in controls. In response to LPS challenge, plasma BHBA concentration decreased in controls and decreased also slightly in the BHBA-infused animals because the BHBA concentration could not be fully maintained despite a rapid increase in BHBA infusion rate. The change in mRNA abundance of citrate synthase in LPS quarters was significant between the 2 treatment groups. The results indicate that elevated circulating BHBA concentration inhibits gluconeogenesis before and during immune response to LPS challenge, likely because BHBA can replace glucose as an energy source. PMID:24679930

Zarrin, M; Wellnitz, O; van Dorland, H A; Gross, J J; Bruckmaier, R M

2014-06-01

165

Eliminative behaviour of dairy cows at pasture  

Microsoft Academic Search

Despite a strong avoidance of grazing near dung patches, cattle have traditionally been considered not to avoid bodily contact with faeces, regardless of any risk of disease. Little is understood of the behaviour of pasture-kept dairy cows at the time of defaecation and therefore, the eliminative behaviour of 40 Holstein-Friesian cows was observed at pasture for 6h each day between

Lindsay Kay Whistance; Liam A. Sinclair; David Richard Arney; Clive Julian Christie Phillips

2011-01-01

166

Productive and reproductive performance of strategically supplemented free grazing prepartum Bunaji cows in the agropastoral farming system.  

PubMed

The effects of prepartum supplementary feeding on the productive and reproductive performance were investigated using grazing gestating Bunaji cows with an average initial body weight of 294.50 +/- 3.75 kg. Twenty cows were allocated to a completely randomized design, with five animals per treatment. The treatments were: A, range grazing (RG); B, RG + 100% corn bran (CB); C, RG + 60% CB + 40% palm kernel cake (PKC), and D, RG + 60% CB + 40% dried brewer's grains (DBG). The average daily gains (ADG) and body condition scores (BCS) of supplemented cows were significantly better than the non-supplemented cows. Postpartum weight loss was markedly reduced in supplemented cows compared to their non-supplemented counterparts. Mean milk offtake and mean milk yield per lactation were significantly lower in non-supplemented cows than the supplemented ones. Among the supplemented cows, ADG, BCS, mean milk offtake and milk yield per lactation were significantly better for cows on treatments C and D than those on treatment B. Though insignificant, longest lactation length (LL) and shortest calving interval were obtained for supplemented cows. Calf's birth weight was similar among the treatments. Milk yield was significantly influenced (R(2) = 0.8601) by cow's weight, BCS and LL. PMID:19184675

Olafadehan, O A; Adewumi, M K

2009-10-01

167

Variation in infection levels with gastrointestinal nematodes in first-year grazing calves in The Netherlands  

Microsoft Academic Search

ELISAs with crude adult Ostertagia and crude adult Cooperia antigens were used in a survey to monitor the levels of gastrointestinal nematode infections of 21 dairy calf herds. This survey was performed at the end of the grazing season of 1994 in The Netherlands. The mean extinction value of antibody levels of each herd was compared with those of four

J. Poot; M. Eysker; T. J. G. M. Lam

1997-01-01

168

Cogeneration on a southeastern dairy  

SciTech Connect

The results of a 5 year study on cogeneration on a dairy operation in Georgia are summarized. Details of system operation and performance are given. Discussion of practical and economic viability of a cogeneration system is provided.

Ross, C.C.; Walsh, J.L.

1987-01-01

169

Modeling the grazing effect on dry grassland carbon cycling with modified Biome-BGC grazing model  

NASA Astrophysics Data System (ADS)

Identifying the factors that determine the carbon source/sink strength of ecosystems is important for reducing uncertainty in the global carbon cycle. Arid grassland ecosystems are a widely distributed biome type in Xinjiang, Northwest China, covering approximately one-fourth the country's land surface. These grasslands are the habitat for many endemic and rare plant and animal species and are also used as pastoral land for livestock. Using the modified Biome-BGC grazing model, we modeled carbon dynamics in Xinjiang for grasslands that varied in grazing intensity. In general, this regional simulation estimated that the grassland ecosystems in Xinjiang acted as a net carbon source, with a value of 0.38 Pg C over the period 1979-2007. There were significant effects of grazing on carbon dynamics. An over-compensatory effect in net primary productivity (NPP) and vegetation carbon (C) stock was observed when grazing intensity was lower than 0.40 head/ha. Grazing resulted in a net carbon source of 23.45 g C m-2 yr-1, which equaled 0.37 Pg in Xinjiang in the last 29 years. In general, grazing decreased vegetation C stock, while an increasing trend was observed with low grazing intensity. The soil C increased significantly (17%) with long-term grazing, while the soil C stock exhibited a steady trend without grazing. These findings have implications for grassland ecosystem management as it relates to carbon sequestration and climate change mitigation, e.g., removal of grazing should be considered in strategies that aim to increase terrestrial carbon sequestrations at local and regional scales. One of the greatest limitations in quantifying the effects of herbivores on carbon cycling is identifying the grazing systems and intensities within a given region. We hope our study emphasizes the need for large-scale assessments of how grazing impacts carbon cycling. Most terrestrial ecosystems in Xinjiang have been affected by disturbances to a greater or lesser extent in the past several decades (e.g., land-use change, timber exploitation, and air pollution). However, regional evaluations that account for all of the local disturbances have been difficult. Data from field measurements play a pivotal role in comparing model simulations with observations.

Luo, Geping; Han, Qifei; Li, Chaofan; Yang, Liao

2014-05-01

170

Dairy 2002: Nutrient Management and the U.S. Dairy Industry in 2002.  

National Technical Information Service (NTIS)

In 2002, the National Animal Health Monitoring System (NAHMS) conducted a study of dairy operations in the United States. NAHMS Dairy 2002 was conducted in 21 major dairy States (see map) and was designed to provide information to both participants and in...

2004-01-01

171

Evaluation of a Whole-Farm Model for Pasture-Based Dairy Systems  

Microsoft Academic Search

In the temperate climate of New Zealand, animals can be grazed outdoors all year round. The pasture is supplemented with conserved feed, with the amount being determined by seasonal pasture growth, genetics of the herd, and stocking rate. The large number of factors that affect production makes it impractical and expensive to use field trials to explore all the farm

P. C. Beukes; C. C. Palliser; K. A. Macdonald; J. A. S. Lancaster; G. Levy; B. S. Thorrold; M. E. Wastney

2008-01-01

172

Economic opportunity survey of small scale dairy farms of the north west province of Cameroon.  

PubMed

An Economic Opportunity Survey was conducted on dairy farms in the North West Province of Cameroon. Results showed that median (range) number of cows in milk per farm was zero point six (0-4) and six (3-12) in the zero grazing and transhumance systems, respectively. Medians (range) of three (0-24) and four (3-10) litres of milk were sold per farm per day, corresponding to 30% and 60% of milk produced. 24% and 13% of total cattle per herd were milking cows in the zero grazing and transhumance systems respectively. Median milk production per cow on one day was two (0-25) and two (1-3) litres. Median calf production interval was 14.5 (12-25) and. 21.5 (14-29) months. More milk produced per day represented the best economic opportunity in both systems while reduced age at first calving and longer lactation length were the next in both. Wastage of milk through spoilage from poor hygiene and lack of cooling was a major problem. Holstein cows, which were in the zero grazing system, had unexpectedly short lactations. Constraints identified led to the setting up of interventions of training and advice for farmers and of better nutrition. PMID:18265867

Bayemi, P H; Webb, E C; Manjeli, Y; Naoussi, P

2007-12-01

173

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

PubMed Central

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 that there is an interaction between housing system and herd size, and that performance and health is not universally better in small free-stalls than in tie-stalls.

2010-01-01

174

Nitrous oxide and greenhouse gas emissions from grazed pastures as affected by use of nitrification inhibitor and restricted grazing regime.  

PubMed

Integration of a restricted grazing regime in winter with the use of a nitrification inhibitor can potentially reduce N2O emissions from grazed pasture systems. A three year field study was conducted to compare annual N2O emission rates from a "tight nitrogen" grazed farmlet with those from a control farmlet. The control farmlet was managed under a conventional rotational all-year grazing regime, while the "tight nitrogen" farmlet was under a similar grazing regime, except during winter and early spring seasons when cows grazed for about 6h per day. A nitrification inhibitor (dicyandiamide, DCD) was applied onto the "tight nitrogen" farmlet immediately after grazing through winter and early spring. A chamber technique was used to measure N2O emissions in several paddocks from each farmlet during three contrasting seasons each year. The IPCC (Intergovernmental Panel on Climate Change) inventory methodology was used to estimate CH4 and indirect N2O emissions and the life cycle assessment (LCA) methodology was used to calculate CO2 emissions from the farm systems. The individual and combined effects of restricted grazing and DCD use on N2O emissions were also determined. During the late spring/summer and autumn periods, N2O emission rates were generally similar between the two farmlets. The use of a restricted grazing regime and DCD reduced N2O emissions from the grazed farmlet during the winter/early spring seasons by 43-55%, 64-79% and 45-60% over each of the three years, respectively. The use of restricted grazing and DCD both resulted in a similar reduction in N2O emissions, but there was no significant further reduction from the combination of these technologies. For the three study years, the annual N2O emission rate from the "tight nitrogen" farmlet was 20% lower, on average, than from the control. Total annual greenhouse gas (GHG) emissions, however, were only 5% less in the "tight nitrogen" system. PMID:23374420

Luo, Jiafa; Ledgard, Stewart F; Lindsey, Stuart B

2013-11-01

175

Agriculture. Dairy Livestock.  

ERIC Educational Resources Information Center

This task-based curriculum guide for agricultural production, specifically for dairy livestock, is intended to help the teacher develop a classroom management system where students learn by doing. Introductory materials include a Dictionary of Occupational Titles job code and title sheet, a task sheet for developing leadership skills, and a task…

Michigan State Univ., East Lansing. Coll. of Agriculture and Natural Resources Education Inst.

176

Comparison of manual versus semiautomatic milk recording systems in dairy goats.  

PubMed

A total of 24 Murciano-Granadina dairy goats in early-midlactation were used to compare the labor time and data collection efficiency of using manual (M) vs. semiautomated (SA) systems for milk recording. Goats were milked once daily in a 2 x 12 parallel platform, with 6 milking units on each side. The M system used visual identification (ID) by large plastic ear tags, on-paper data recording, and data manually uploaded to a computer. The SA system used electronic ID, automatic ID, manual data recording on reader keyboard, and automatic data uploading to computer by Bluetooth connection. Data were collected for groups of 2 x 12 goats for 15 test days of each system during a period of 70 d. Time data were converted to a decimal scale. No difference in milk recording time between M and SA (1.32 +/- 0.03 and 1.34 +/- 0.03 min/goat, respectively) was observed. Time needed for transferring data to the computer was greater for M when compared with SA (0.20 +/- 0.01 and 0.05 +/- 0.01 min/goat). Overall milk recording time was greater in M than in SA (1.52 +/- 0.04 vs. 1.39 +/- 0.04 min/goat), the latter decreasing with operator training. Time for transferring milk recording data to the computer was 4.81 +/- 0.34 and 1.09 +/- 0.10 min for M and SA groups of 24 goats, respectively, but only increased by 0.19 min in SA for each additional 24 goats. No difference in errors of data acquisition was detected between M and SA systems during milk recording (0.6%), but an additional 1.1% error was found in the M system during data uploading. Predicted differences between M and SA increased with the number of goats processed on the test-day. Reduction in labor time cost ranged from euro0.5 to 12.9 (US$0.7 to 17.4) per milk recording, according to number of goats from 24 to 480 goats and accounted for 40% of the electronic ID costs. In conclusion, electronic ID was more efficient for labor costs and resulted in fewer data errors, the benefit being greater with trained operators and larger goat herds. PMID:18349236

Ait-Saidi, A; Caja, G; Carné, S; Salama, A A K; Ghirardi, J J

2008-04-01

177

The detectability of nitrous oxide mitigation efficacy in intensively grazed pastures using a multiple-plot micrometeorological technique  

NASA Astrophysics Data System (ADS)

Methodologies are required to verify agricultural greenhouse gas mitigation at scales relevant to farm management. Micrometeorological techniques provide a viable approach for comparing fluxes between fields receiving mitigation treatments and control fields. However, they have rarely been applied to spatially verifying treatments aimed at mitigating nitrous oxide emission from intensively grazed pastoral systems. We deployed a micrometeorological system to compare N2O flux among several ~1.5 ha plots in intensively grazed dairy pasture. The sample collection and measurement system is referred to as the Field-Scale Nitrous Oxide Mitigation Assessment System (FS-NOMAS) and used a tuneable diode laser absorption spectrometer to measure N2O gradients to high precision at four locations along a 300 m transect. The utility of the FS-NOMAS to assess mitigation efficacy depends largely on its ability to resolve very small vertical N2O gradients. The performance of the FS-NOMAS was assessed in this respect in laboratory and field-based studies. The FS-NOMAS could reliably resolve gradients of 0.039 ppb between a height of 0.5 and 1.0 m. The gradient resolution achieved corresponded to the ability to detect an inter-plot N2O flux difference of 26 ?g N2O-N m-2 h-1 under the most commonly encountered conditions of atmospheric mixing (quantified here by a turbulent transfer coefficient), but this ranged from 11 to 59 ?g N2O-N m-2 h-1 as the transfer coefficient ranged between its 5th and 95th percentile. Assuming a likely value of 100 ?g N2O-N m-2 h-1 for post-grazing N2O fluxes from intensively grazed New Zealand dairy pasture, the system described here would be capable of detecting a mitigation efficacy of 26% for a single (40 min) comparison. We demonstrate that the system has considerably greater sensitivity to treatment effects by measuring cumulative fluxes over extended periods.

McMillan, A. M. S.; Harvey, M. J.; Martin, R. J.; Bromley, A. M.; Evans, M. J.; Mukherjee, S.; Laubach, J.

2014-05-01

178

Reduction of Phosphorus in Dairy Effluent with a Constructed Wetland-Steel Slag Filter System  

Microsoft Academic Search

Aquatic ecosystems can be disturbed by pollutant sources such as untreated urban and agricultural runoff. In Vermont, runoff from dairy farms containing phosphorus (P) can be transported to surface waters where increased biological productivity can result in blue-green algae proliferation and eutrophication. Excess algae and eutrophication can cause depleted oxygen levels, high turbidity, reduced aquatic species diversity, undesirable taste, and

Stephanie Chang

2009-01-01

179

Nutrient Movement and Removal in a Switchgrass Biomass–Filter Strip System Treated with Dairy Manure  

Microsoft Academic Search

Bosque River have been attributed in part to the density of dairy cows (Bos taurus ) and the proportion of land Manure use on cropland has raised concern about nutrient contami- area used for manure application on certain microwater- nation of surface and ground waters. Warm-season perennial grasses may be useful in filter strips to trap manure nutrients and as

Matt A. Sanderson; Ronald M. Jones; Marshall J. McFarland; Jason Stroup; Roderick L. Reed; James P. Muir

2001-01-01

180

The use and value of information systems as evaluated by dairy and specialty crop farm managers.  

PubMed

Little recent research is available about where specific types of farm managers search for information about better production practices. The objective of this study was to investigate what information sources managers used and how they rated the usefulness of each source. The authors administered mail questionnaires to probability samples from sampling frames they developed for four groups: dairy and fresh market vegetable producers from Wisconsin and berry and nursery producers from a multistate region. Questionnaire items asked operation managers to check off, from a list of information sources, those that they used in the last year to learn about new equipment or procedures to improve their operations and then to rate the usefulness of each source. In the last year, nursery, dairy, and berry managers most often used information from print media (63% to 84%), followed by other farmers (50% to 80%). Fresh market vegetable growers used conferences (60%) most often, followed by print media (41%). The information source rated most useful was "other farmers" for the nursery, dairy, and fresh market vegetable managers. Nursery and fresh market vegetable managers rated conferences as second most useful, whereas dairy managers rated print media second. Berry managers were not asked about usefulness. Farm manager information behavior exhibits some common features but is also specific to their operation type. Research and outreach efforts intending to communicate information to farm managers may be able to be more efficient at reaching and persuading their intended audience if they first investigate manager information behavior. PMID:19657882

Chapman, Larry J; Newenhouse, Astrid C; Karsh, Ben-Tzion; Taveira, Alvaro D

2009-01-01

181

Bacteriophage-resistance systems in dairy starter strains: molecular analysis to application  

Microsoft Academic Search

Starter inhibition by bacteriophage infection in dairy fermentations can limit the usage of specific bacterial strains used in the manufacture of Cheddar, Mozzarella and other cheeses and can result in substantial economic losses. A variety of practical measures to alleviate the problem of phage infection have been adopted over the years but has invariably resulted in a very limited number

Aidan Coffey; R. Paul Ross

2002-01-01

182

Total Bacterial Count in Soft-Frozen Dairy Products by Impedance Biosensor System  

Microsoft Academic Search

In order to guarantee product safety in the dairy industry, the microbial concentration of food must be ultimately evaluated by means of the standard plate count (SPC) technique, reliable but also slow and difficult to implement in automatic form. On the other hand, detection of bacterial concentration by means of classic impedance microbiology is very attractive due to faster response

Marco Grossi; R. Lazzarini; A. Pompei; D. Matteuzzi; B. Ricco; M. Lanzoni

2009-01-01

183

Economics of fertility in high-yielding dairy cows on confined TMR systems.  

PubMed

The objective of this review paper was to summarise the latest findings in dairy cattle reproductive economics with an emphasis on high yielding, confined total mixed ration systems. The economic gain increases as the reproductive efficiency improves. These increments follow the law of diminishing returns, but are still positive even at high reproductive performance. Reproductive improvement results in higher milk productivity and, therefore, higher milk income over feed cost, more calf sales and lower culling and breeding expenses. Most high-yielding herds in the United States use a combination of timed artificial insemination (TAI) and oestrous detection (OD) reproductive programme. The ratio of achievable pregnancies between OD and TAI determines the economic value difference between both and their combinations. Nonetheless, complex interactions between reproductive programme, herd relative milk yield, and type of reproductive programme are reported. For example, higher herd relative milk yield would favour programme relying more on TAI. In addition, improved reproductive efficiency produces extra replacements. The availability of additional replacements could allow more aggressive culling policies (e.g. less services for non-pregnant cows) to balance on-farm supply and demand of replacements. Balancing heifer replacement availability in an efficient reproductive programme brings additional economic benefits. New technologies such as the use of earlier chemical tests for pregnancy diagnosis could be economically effective depending on the goals and characteristics of the farm. Opportunities for individual cow reproductive management within defined reproductive programme exist. These decisions would be based on economic metrics derived from the value of a cow such as the value of a new pregnancy, the cost of a pregnancy loss, or the cost of an extra day open. PMID:24679357

Cabrera, V E

2014-05-01

184

Sistema de pastejo, rotenona e controle de parasitas em bovinos cruzados: efeito no ganho de peso e no parasitismo Grazing systems, rotenone and parasites control in crossbred calves: effect on live weight gain and on parasites burdens  

Microsoft Academic Search

Practices for endo and ectoparasite control in beef cattle were evaluated in two independent experiments. First, the effects of rotenone® on Rhipicephalus (Boophilus) microplus ticks were evaluated in vitro and in experimentally infected calves. In the second trial, the effects of grazing systems associated with endo and ectoparasite treatments on parasite burden and weight gain of naturally parasited animals were

João B. Catto; Ivo Bianchin; Jânio M. Santurio; Gelson L. D. Feijó; Armindo N. Kichel; José M. da Silva

2009-01-01

185

36 CFR 222.53 - Grazing fees in the East-noncompetitive procedures.  

Code of Federal Regulations, 2013 CFR

...fair market value procedures. These rules do not apply to grazing fees on National Forest System lands in Oklahoma or National Grasslands in Texas. Grazing permits under the noncompetitive fee method in the East are subject to the rules governing grazing...

2013-07-01

186

Ruminant Grazing of Cover Crops: Effects on Soil Properties and Agricultural Production  

ERIC Educational Resources Information Center

Integrating livestock into a cropping system by allowing ruminant animals to graze cover crops may yield economic and environmental benefits. The effects of grazing on soil physical properties, soil organic matter, nitrogen cycling and agricultural production are presented in this literature review. The review found that grazing cover crops…

Poffenbarger, Hanna

2010-01-01

187

Community responses of arthropods to a range of traditional and manipulated grazing in shortgrass steppe.  

PubMed

Responses of plants to grazing are better understood, and more predictable, than those of consumers in North American grasslands. In 2003, we began a large-scale, replicated experiment that examined the effects of grazing on three important arthropod groups-beetles, spiders, and grasshoppers-in shortgrass steppe of north-central Colorado. We investigated whether modifications of the intensity and seasonality of livestock grazing alter the structure and diversity of macroarthropod communities compared with traditional grazing practices. Treatments represented a gradient of grazing intensity by cattle and native herbivores: long-term grazing exclosures; moderate summer grazing (the traditional regime); intensive spring grazing; intensive summer grazing; and moderately summer-grazed pastures also inhabited by black-tailed prairie dogs (Cynomys ludovicianus Ord). Beetles and spiders were the most common groups captured, comprising 60% and 21%, respectively, of 4,378 total pitfall captures. Grasshopper counts were generally low, with 3,799 individuals observed and densities <4 m(-2). Two years after treatments were applied, vegetation structure differed among grazing treatments, responding not only to long-term grazing conditions, but also to the short-term, more-intensive grazing manipulations. In response, arthropods were, in general, relatively insensitive to these grazing-induced structural changes. However, species-level analyses of one group (Tenebrionidae) revealed both positive and negative effects of grazing treatments on beetle richness and activity-density. Importantly, these responses to grazing were more pronounced in a year when spring-summer rainfall was low, suggesting that both grazing and precipitation-which together may create the greatest heterogeneity in vegetation structure-are drivers of consumer responses in this system. PMID:24780073

Newbold, T A Scott; Stapp, Paul; Levensailor, Katherine E; Derner, Justin D; Lauenroth, William K

2014-06-01

188

Children's exposures to farm worksite hazards on management-intensive grazing operations.  

PubMed

Agricultural injuries continue to be an important source of childhood mortality and morbidity. There is an agreement within the injury prevention community that environmental modification is the most effective strategy for injury prevention. A growing trend among dairy farmers in the upper Midwest and Northeast regions of the United States is the adoption of management-intensive grazing (MIG) as a new technique for dairy management that actually encompasses environmental modification, decreasing the reliance on and use of tractors and machinery (major sources of fatal and nonfatal injuries to children). The purpose of this study was to explore how restructuring the work and the work environment through the use of MIG may affect children's exposure to farm worksite hazards. The study specifically focused on the most hazardous farm worksite exposures for children based on injury surveillance data (tractors, machinery, large animals, heights, and water sources). An online survey was sent to 68 Wisconsin agricultural extension agents knowledgeable about dairy operations in their counties to collect data regarding their perceptions of potential childhood farm safety hazards on MIG operations. A total of 31 surveys were returned using the online survey system, resulting in a 46% response rate. Survey results suggest that children on MIG operations do in fact have decreased exposure to farm machinery. However, there was a perceived increase in children's overall worksite exposure, in addition to specific increases in exposure to all-terrain vehicles and animals. Adoption of a MIG system clearly involves changes in exposures for children, and understanding the full impact of these changes will require further study of the effects of these exposure tradeoffs on the risks for injuries of varying nature and severity. PMID:19437277

Fisher, Regina M; Berg, Richard L; Marlenga, Barbara

2009-01-01

189

Grazing sericea lespedeza for control of gastrointestinal nematodes in lambs.  

PubMed

Alternatives to chemical dewormers are needed to counter anthelmintic resistance and improve worm control in organic management systems. The objective was to examine the effectiveness of grazing sericea lespedeza (SL) compared with grass pastures for control of gastrointestinal nematodes (GIN) in lambs. In Experiment 1, Katahdin lambs grazed bermudagrass (BG; n=14), tall fescue (TF; n=7), or SL (n=19) pastures during early summer months. In Experiment 2, lambs grazed TF (n=15) or SL (n=13) pastures during late summer. Stocking rate of pastures was based on forage availability; additional lambs grazed pastures in Experiment 2, but were not sampled. Lambs were dewormed with 0.5 g COWP if FAMACHA(©) score was >3. In Experiment 1, FEC were reduced within 35 days in SL compared with BG lambs (forage by time, P=0.03). The PCV was more resilient to changes over time in SL compared with other groups of lambs (forage by time, P=0.001). In Experiment 2, FEC were lower (P=0.02) and PCV tended to be higher (P=0.09) in lambs grazing SL compared with TF forage. Incidence of deworming was similar among forage groups in both experiments. Grazing SL reduced FEC in lambs in early and late summer, despite reluctance by lambs to graze. Grazing forage and selective deworming using COWP was effective in lambs. PMID:22226762

Burke, J M; Miller, J E; Mosjidis, J A; Terrill, T H

2012-05-25

190

WASHINGTON DAIRIES  

EPA Science Inventory

The dairy_wa.zip file is a zip file containing an Arc/Info export file and a text document. Note the DISCLAIM.TXT file as these data are not verified. Map extent: statewide. Input Source: Address database obtained from Wa Dept of Agriculture. Data was originally developed und...

191

Organic or conventional? Optimal dairy farming technology under the EU milk quota system and organic subsidies  

Microsoft Academic Search

This paper assesses the competitiveness of organic and conventional dairy farms under different milk market and organic farming policy scenarios. We use a DEA-based model to estimate for each policy scenario the sample farms’ profit potential in both technologies. The model enables identification of a farm’s optimal technology based on its input–output observations. The empirical analysis is based on the

Gunnar Breustedt; Uwe Latacz-Lohmann; Torben Tiedemann

2011-01-01

192

Thermophilic biogas plant for dairy manure treatment as combined power and heat system in cold regions  

Microsoft Academic Search

A 60-m3 anaerobic digester was installed next to a free barn, and was operated with dairy manure at a digester temperature of 55 °C. The average loading rate in the digester was 6.75 kg\\/m3\\/day with a hydraulic retention time of 13 days. In the coldest season with an average ambient temperature of ?23 °C and manure temperature of 2 °C the average

K. Aoki; K. Umetsu; K. Nishizaki; J. Takahashi; T. Kishimoto; M. Tani; O. Hamamoto; T. Misaki

2006-01-01

193

Effects of energy supplementation on productivity of dual-purpose cows grazing in a silvopastoral system in the tropics.  

PubMed

The aim of the present work was to evaluate milk yield, postpartum (pp) ovarian activity and pregnancy rate in dual-purpose cows grazing Cynodon nlemfuensis and browsing L. leucocephala, with or without energy supplementation. Twenty-four Bos taurus × B. indicus cows were divided in two groups from calving to 70 days post-calving: supplemented group (SG) with ground sorghum grain offered at 0.4% of live weight at calving and control group (CG) without supplement. There was a trend for milk yield (kg day(-1)) to be greater (p = 0.08) for SG (10.55 ± 0.51) compared to CG (9.53 ± 0.61), although without differences in fat (0.42 ± 0.02 vs. 0.38 ± 0.03 kg day(-1)), protein (0.29 ± 0.02 vs. 0.29 ± 0.02 kg day(-1)) or lactose (0.49 ± 0.02 vs. 0.49 ± 0.03 kg day(-1)) concentration. Populations of large, medium and small follicles were similar between treatments. Percentage of cows which showed corpus luteum tended to be greater in SG (50%), compared to CG (33%). Supplemented cows tended to have a shorter calving-first corpus luteum interval (40 ± 10 vs. 51 ± 10 days) and had a significantly higher (? (2) = 0.03) pregnancy rate (42% vs. 0%). It is concluded that energy supplementation helped to improve ovarian activity and pregnancy rate. Since supplementation did not avoid loss of body condition, the higher pregnancy rate in SG suggests beneficial effects of supplementation probably mediated by metabolic hormones. PMID:22193937

Tinoco-Magaña, Juan Carlos; Aguilar-Pérez, Carlos Fernando; Delgado-León, Roger; Magaña-Monforte, Juan Gabriel; Ku-Vera, Juan Carlos; Herrera-Camacho, Jose

2012-06-01

194

Simulating Grazing Impacts on Ecosystem Carbon Dynamics in the Green River Basin, Wyoming  

NASA Astrophysics Data System (ADS)

Grazing is one of the key disturbances on semi-arid grasslands. To understand the grazing impacts on carbon (C ) dynamics in these grasslands can help to create livestock management in a sustainable way. We used the General Ensemble Biogeochemical Modeling System (GEMS) to study the effects of grazing intensity on ecosystem carbon dynamics between 1970 and 1999 across the Green River Basin (GRB) in southwest Wyoming. The National Land Cover Database and multi-year MODIS Net Primary Production (NPP) data were used as inputs to produce the spatial maps of carbon dynamics in GRB. We set three scenarios based on different levels of grazing intensity: no grazing, light grazing, and moderate grazing. Our results indicate that if potential vegetation production (which is defined by the biological traits of the grass species) does not change, excluding grazing on semi-arid grasslands reduces grassland production. The moderate-grazing scenario resulted in the highest production (5.1 TgC), followed by the light-grazing scenario (4.6 TgC) and no-grazing scenario (4.3 TgC). The NPP differences between grazing and no-grazing scenarios varied annually and were significantly affected by annual precipitation and temperature. Excluding grazing for 30 years on the grasslands increased the ecosystem carbon by 6.7% while reducing grazing to light-grazing increased 3.6%. The spatial distribution of ecosystem carbon change wereas significantly impacted by initial ecosystem carbon storage, vegetation production, and carbon removed from ecosystem. The carbon dynamic maps generated by our approach can be used as a diagnostic tool for rangeland managements.

li, Z.; Liu, S.; Tan, Z.; Young, C.

2011-12-01

195

Local and Systemic Immune Mechanisms Underlying the Anti-Colitis Effects of the Dairy Bacterium Lactobacillus delbrueckii  

PubMed Central

Several probiotic bacteria have been proposed for treatment or prevention of inflammatory bowel diseases (IBD), showing a protective effect in animal models of experimental colitis and for some of them also in human clinical trials. While most of these probiotic bacteria are isolated from the digestive tract, we recently reported that a Lactobacillus strain isolated from cheese, L. delbrueckii subsp. lactis CNRZ327 (Lb CNRZ327), also possesses anti-inflammatory effects in vitro and in vivo, demonstrating that common dairy bacteria may be useful in the treatment or prevention of IBD. Here, we studied the mechanisms underlying the protective effects of Lb CNRZ327 in vivo, in a mouse dextran sodium sulfate (DSS) colitis model. During colitis, Lb CNRZ327 modulated the production of TGF-?, IL-6, and IL-12 in colonic tissue and of TGF-? and IL-6 in the spleen, and caused an expansion of CD4+Foxp3+ regulatory T cells in the cecal lymph nodes. Moreover, a strong tendency to CD4+Foxp3+ expansion was also observed in the spleen. The results of this study for the first time show that orally administered dairy lactobacilli can not only modulate mucosal but also systemic immune responses and constitute an effective treatment of IBD.

Santos Rocha, Clarissa; Gomes-Santos, Ana Cristina; Garcias Moreira, Thais; de Azevedo, Marcela; Diniz Luerce, Tessalia; Mariadassou, Mahendra; Longaray Delamare, Ana Paula; Langella, Philippe; Maguin, Emmanuelle; Azevedo, Vasco; Caetano de Faria, Ana Maria

2014-01-01

196

Fate and occurrence of steroids in swine and dairy cattle farms with different farming scales and wastes disposal systems.  

PubMed

Fate and occurrence of fourteen androgens, four estrogens, five glucocorticoids and five progestagens were investigated in three swine farms and three dairy cattle farms with different farming scales and wastes disposal systems in China. Twenty-one, 22, and 12 of total 28 steroids were detected in feces samples with concentrations ranging from below method limit of quantitation (dairy cattle and human sources, respectively. PMID:22835499

Liu, Shan; Ying, Guang-Guo; Zhang, Rui-Quan; Zhou, Li-Jun; Lai, Hua-Jie; Chen, Zhi-Feng

2012-11-01

197

The effect of target postgrazing height on sward clover content, herbage yield, and dairy production from grass-white clover pasture.  

PubMed

White clover (Trifolium repens) is an important legume for grazed grassland that can increase the profitability and environmental sustainability of milk production. Previous experiments on mown grass-clover plots suggest that low postgrazing heights (PGH) can increase sward clover content and herbage production. However, this has not been tested in actual strip or rotational grazing systems with dairy cows. Furthermore, lowering PGH in grass-only swards (typically perennial ryegrass without white clover) has previously been associated with reduced milk yields per cow. The objective of this experiment was to investigate the effect of PGH by dairy cows on clover content, herbage production, and milk production from strip-grazed grass-white clover swards in Ireland. Three target PGH treatments of 4, 5, and 6 cm were in place for entire grazing seasons (February to November) for 3 consecutive years (2007 to 2009). Each treatment had a mean of 21 Holstein-Friesian dairy cows that strip-grazed a mean annual area of 10.2 ha. Postgrazing height was measured twice a day with a rising plate meter, and cows were moved to the next strip once the target PGH was reached. Annual fertilizer nitrogen input was 90 kg of N/ha for each treatment. The PGH treatment did not significantly affect annual milk yield (6,202 kg/cow), solids-corrected milk yield (6,148 kg/cow), fat, protein, or lactose yields (265, 222, and 289 kg/cow, respectively), cow liveweight (592 kg) or body condition score (3.01). The PGH treatment also had no significant effect on sward white clover content (196 g/kg). However, herbage production of both grass and clover were significantly higher with the 4-cm PGH treatment compared with the 6-cm treatment. Mean annual herbage yields were 11.1, 10.2, and 9.1 t of organic matter (OM)/ha for the 4-, 5-, and 6-cm PGH treatments, respectively. The lower herbage production in the 6-cm PGH treatment resulted in lower annual silage production, greater housing requirements, and a substantially higher net silage deficit (-1,917 kg of OM/cow) compared with the 5- or 4-cm treatments (-868 and -192 kg of OM/cow, respectively). Grazing to a PGH of 4 cm is therefore recommended for grass-white clover swards. PMID:23332838

Phelan, P; Casey, I A; Humphreys, J

2013-03-01

198

Impacts of future climate scenarios on the balance between productivity and total greenhouse gas emissions from pasture based dairy systems in south-eastern Australia  

Microsoft Academic Search

The challenge for agriculture is to increase production in warmer climates in order to meet the demands of an increasing global population, while also meeting targets for reduced greenhouse gas (GHG) emissions. Our aim was to quantify the net effect of future climate scenarios on the productivity and total GHG emissions from pasture based dairy systems in 4 regions of

B. R. Cullen; R. J. Eckard

2011-01-01

199

Dairy farm cost efficiency.  

PubMed

A stochastic cost equation was estimated for US dairy farms using national data from the production year 2000 to determine how farmers might reduce their cost of production. Cost of producing a unit of milk was estimated into separate frontier (efficient) and inefficiency components, with both components estimated as a function of management and causation variables. Variables were entered as impacting the frontier component as well as the efficiency component of the stochastic curve because a priori both components could be impacted. A factor that has an impact on the cost frontier was the number of hours per day the milking facility is used. Using the milking facility for more hours per day decreased frontier costs; however, inefficiency increased with increased hours of milking facility use. Thus, farmers can decrease costs with increased utilization of the milking facility, but only if they are efficient in this strategy. Parlors compared with stanchions used for milking did not decrease frontier costs, but decreased costs because of increased efficiency, as did the use of a nutritionist. Use of rotational grazing decreased frontier costs but also increased inefficiency. Older farmers were less efficient. PMID:17106126

Tauer, L W; Mishra, A K

2006-12-01

200

A LYSIMETER STUDY TO INVESTIGATE THE EFFECT OF DAIRY EFFLUENT AND UREA ON CATTLE URIN N LOSSES, PLANT UPTAKE, AND SOIL RETENTION  

EPA Science Inventory

Loss of nitrate (NO3-) from grazing land is a major cause for surface and ground water contamination. These losses can further increase when other N sources apply to grazing land. The objectives of this work were 1) to study the impact of either dairy effl...

201

The use of hormonal treatments to improve the reproductive performance of lactating dairy cows in feedlot or pasture-based management systems.  

PubMed

Hormonal interventions have been used to increase the probability of estrous detection and insemination, and to increase pregnancy rates of dairy cattle under a variety of management systems. The present review addresses the basic principles of hormonal intervention and presents typical examples that illustrate the methodology. The hormones used to control the estrous cycle mimic the reproductive hormones found within the normal cow. Most estrous synchronization systems employ a method for controlling follicular wave development, promoting ovulation in anestrous cows, regressing the corpus luteum in cyclic cows, and synchronizing estrus and (or) ovulation at the end of treatment. A wide range of reproductive systems are in place on dairy farms. In most herds, a non-intervention period is practiced where postpartum cows are observed estrus estrus. Cows not observed in estrus are then treated. A number of studies in pasture-based and confinement systems have demonstrated net benefits of whole-herd synchronization. Despite the advantages of whole-herd reproductive programs, their uptake has been inconsistent globally. The benefits of a timed artificial insemination (AI) system increase under conditions of poor estrous detection rate and poor conception rate. The unpopular nature of timed AI programs in pasture-fed cows relates to high rates of estrous detection and conception for pasture-based dairying. Regardless of production system, some cows must be re-inseminated because they are not pregnant after first insemination. The presence of "phantom cows" (non-pregnant cows that do not return to estrus) creates a serious reproductive challenge for both pasture-based and confinement-style operations. Early pregnancy diagnosis and second insemination timed AI may reduce the effects of phantom cows on dairy herds. Fundamental research into anestrous, the hormonal control of the estrous cycle, and early pregnancy detection should elucidate new methods that can be used to strengthen reproductive programs on dairy farms. PMID:15271476

Lucy, M C; McDougall, S; Nation, D P

2004-07-01

202

Effectiveness of dairy wastewater treatment in a bioreactor based on the integrated technology of activated sludge and hydrophyte system.  

PubMed

The aim of this study was to determine the effectiveness of dairy wastewater treatment in the integrated technology based on the simultaneous use of the activated sludge method (AS) and a hydrophyte system (HS) (AS-HS), in this case, common reed (Phragmites australis) or common cattail (Typha latifolia). Experiments were conducted in an innovative reactor exploited in the fractional-technical scale at the loads of 0.05 mg BOD5/mg.d.m. d (biochemical oxygen demand) and 0.10 mg BOD5/mg.d.m d. The AS--HS enabled improving the removal effectiveness ofbiogenes characterized by concentrations of Ntot., N-NH4 and Ptot. In contrast, the integrated system had no significant reducing effect either on concentrations of organic compounds characterized by BOD5 and chemical oxygen demand parameters or on the structure of AS in the sequencing batch-type reactors. PMID:24701933

Debowski, M; Zieli?ski, M; Krzemieniewski, M; Rokicka, M; Kupczyk, K

2014-01-01

203

Reproduction and lactational performance of cattle in a smallholder dairy system in Zimbabwe.  

PubMed

A study was conducted in two adjacent locations. Nharira (communal) and Lancashire (small-scale commercial) farming areas in Zimbabwe to characterize the breeds and evaluate the reproductive and lactation performance of dairy cattle under smallholder management. The types of cows identified were Friesian, Jersey and Red Dane, and an indigenous Sanga breed called the Mashona and its crossbreds. Both sectors used more exotic and crossbred cows than indigenous cows. The mean monthly weights of the dairy cows were higher in Lancashire than in Nharira and the calving intervals were longer in Nharira than in Lancashire. The mean age at first calving was higher and the mean total lactation yields were greater in Nharira than in Lancashire, but the mean 305-day lactation yields were not significantly different. The mean lactation lengths were longer for the cows from Nharira. It was concluded that the reproductive and lactation performances were low. The calving intervals were extended, probably owing to suboptimal nutrition and heat stress, particularly during the dry season, and to poor management practices, such as delayed mating due to the poor availability of bulls. PMID:12735703

Masama, E; Kusina, N T; Sibanda, S; Majoni, C

2003-04-01

204

Grazing incidence beam expander  

SciTech Connect

A Grazing Incidence Beam Expander (GIBE) telescope is being designed and fabricated to be used as an equivalent end mirror in a long laser resonator cavity. The design requirements for this GIBE flow down from a generic Free Electron Laser (FEL) resonator. The nature of the FEL gain volume (a thin, pencil-like, on-axis region) dictates that the output beam be very small. Such a thin beam with the high power levels characteristic of FELs would have to travel perhaps hundreds of meters or more before expanding enough to allow reflection from cooled mirrors. A GIBE, on the other hand, would allow placing these optics closer to the gain region and thus reduces the cavity lengths substantially. Results are presented relating to optical and mechanical design, alignment sensitivity analysis, radius of curvature analysis, laser cavity stability analysis of a linear stable concentric laser cavity with a GIBE. Fabrication details of the GIBE are also given.

Akkapeddi, P.R.; Glenn, P.; Fuschetto, A.; Appert, Q.; Viswanathan, V.K.

1985-01-01

205

The effect of lameness on the fertility of dairy cattle in a seasonally breeding pasture-based system.  

PubMed

The effect of lameness on the fertility of dairy cattle is well recognized. But, the effect of lameness on the fertility of seasonally breeding cattle in pasture-based systems is less well characterized. This prospective cohort study of 463 cows on 1 farm in the lower North Island of New Zealand was designed to assess the effect of clinical lameness, as identified by farm staff, on the hazard of conception after the planned start-of-mating date. A Cox proportional hazards model with time-varying covariates was used. After controlling for the effect of parity, breed, body weight at calving, and calving-to-planned start of mating interval, the daily hazard of conception for cows identified as lame was 0.78 (95% confidence interval: 0.68-0.86) compared with non-lame cows. Lame cows took 12 d longer to get pregnant compared with their non-lame counterparts. PMID:22032371

Alawneh, J I; Laven, R A; Stevenson, M A

2011-11-01

206

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

PubMed

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. PMID:24856987

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

2014-08-01

207

25 CFR 167.12 - Grazing fees.  

Code of Federal Regulations, 2011 CFR

... Grazing fees. 167.12 Section 167.12 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER NAVAJO GRAZING REGULATIONS § 167.12 Grazing fees. Grazing fees shall not be charged at this time. 1 1...

2011-04-01

208

Grazing Rental Appraisal Data: Arizona.  

National Technical Information Service (NTIS)

Information contained on these microfiche pertain to data collected during the course of field work, conducted from July 1982 through November 1983, associated with the 'Grazing Rental Appraisal Project'. The Appraisal is one part of a comprehensive grazi...

P. B. Tittman C. E. Brownell

1983-01-01

209

Grazing Rental Appraisal Data: Oregon.  

National Technical Information Service (NTIS)

Information contained on these microfiche pertain to data collected during the course of field work, conducted from July 1982 through November 1983, associated with the 'Grazing Rental Appraisal Project'. The Appraisal is one part of a comprehensive grazi...

P. B. Tittman C. E. Brownell

1983-01-01

210

Grazing Rental Appraisal Data: Montana.  

National Technical Information Service (NTIS)

Information contained on these microfiche pertain to data collected during the course of field work, conducted from July 1982 through November 1983, associated with the 'Grazing Rental Appraisal Project'. The Appraisal is one part of a comprehensive grazi...

P. B. Tittman C. E. Brownell

1983-01-01

211

Grazing Rental Appraisal Data: Oklahoma.  

National Technical Information Service (NTIS)

Information contained on these microfiche pertain to data collected during the course of field work, conducted from July 1982 through November 1983, associated with the 'Grazing Rental Appraisal Project'. The Appraisal is one part of a comprehensive grazi...

P. B. Tittman C. E. Brownell

1983-01-01

212

Aberrations for Grazing Incidence Optics.  

National Technical Information Service (NTIS)

Large number of grazing incidence telescope configurations have been designed and studied. Wolte1 telescopes are commonly used in astronomical applications. Wolter telescopes consist of a paraboloidal primary mirror and a hyperboloidal or an ellipsoidal s...

T. T. Saha

2008-01-01

213

Factors that influence the efficiency of beef and dairy cattle recording system in Kenya: A SWOT-AHP analysis.  

PubMed

Animal recording in Kenya is characterised by erratic producer participation and high drop-out rates from the national recording scheme. This study evaluates factors influencing efficiency of beef and dairy cattle recording system. Factors influencing efficiency of animal identification and registration, pedigree and performance recording, and genetic evaluation and information utilisation were generated using qualitative and participatory methods. Pairwise comparison of factors was done by strengths, weaknesses, opportunities and threats-analytical hierarchical process analysis and priority scores to determine their relative importance to the system calculated using Eigenvalue method. For identification and registration, and evaluation and information utilisation, external factors had high priority scores. For pedigree and performance recording, threats and weaknesses had the highest priority scores. Strengths factors could not sustain the required efficiency of the system. Weaknesses of the system predisposed it to threats. Available opportunities could be explored as interventions to restore efficiency in the system. Defensive strategies such as reorienting the system to offer utility benefits to recording, forming symbiotic and binding collaboration between recording organisations and NARS, and development of institutions to support recording were feasible. PMID:20676763

Wasike, Chrilukovian B; Magothe, Thomas M; Kahi, Alexander K; Peters, Kurt J

2011-01-01

214

Maternal Effects of Japanese Shorthorn Cows on the Growth of Embryo-transferred Japanese Black Calves in a Cow-calf Grazing System  

PubMed Central

The growth performance of embryo-transferred Japanese Black calves that were born from, and suckled by, Japanese Shorthorn cows in a cow-calf grazing system (BS-group, n = 5) was compared to that of Japanese Black calves from Japanese Black cows in a cowshed (BB-group, n = 5). The daily weight gain from birth to 1 month was higher in the BS-group than in the BB-group (p<0.01), and the same trend (p<0.05) was observed at 2 and 3 months of age. This resulted in body weight that was significantly higher for the BS-group between 1 and 3 months of age than what was observed for the BB-group (p<0.05). Heart girth was significantly greater in the BS-group than in the BB-group throughout the experimental period (p<0.01), and chest depth and withers height in the BS-group were significantly greater from 2 to 4 months of age (p<0.05) and at 4 months of age only (p<0.05). No difference in body length (p>0.05) was observed between the groups. These results suggest that the maternal effect of Japanese Shorthorn cows was positive for embryo-transferred Japanese Black calf growth during the early suckling stage. As Japanese Black calves are traded at a high price on the Japanese market, we conclude that this proposed production system is likely to improve the profitability of herd management in upland Japan.

Yamaguchi, Manabu; Ikeda, Kentaro; Takenouchi, Naoki; Higashiyama, Masakazu; Watanabe, Akira

2013-01-01

215

Productive performance and urinary excretion of mimosine metabolites by hair sheep grazing in a silvopastoral system with high densities of Leucaena leucocephala.  

PubMed

The aim of this study was to evaluate daily weight gain (DWG), total dry matter (DM) intake, rumen degradability of forage, and urinary excretion of mimosine metabolites by hair sheep in a silvopastoral system with high densities of Leucaena leucocephala. A completely randomized design was carried out with two treatments: treatment 1 (T1) silvopastoral system with leucaena at a density of 35,000 plants/ha and treatment 2 (T2), leucaena at a density of 55,000 plants/ha. Leucaena was associated with tropical grasses Panicum maximum and Cynodon nlemfluensis. Twenty-four male Pelibuey lambs of 23.2 ± 3.4 kg live weight (LW) were used (12 lambs per treatment). Results showed differences (P < 0.05) in DWG of T1 (106.41 ± 11.66 g(-1) sheep(-1)) with respect to that of T2 (81.33 ± 11.81 g(-1) sheep). Voluntary intake was higher in lambs from T1 (83.81 ± 04.07 g DM/kg LW(0.75)) with respect to that from T2 (71.67 ± 8.12 g DM/kg LW(0.75)). There was a difference in color of urine between sheep of T1 and T2, the latter giving positive results for the presence of metabolites derived from mimosine (3-4 dihydroxypyridine and 2-3 dihydroxy pyridone). Rumen degradability of DM of L. leucocephala was higher (P < 0.05) compared to that of P. maximum and C. nlemfluensis (72.94 ± 0.40 vs. 67.06?±?1.50 and 63.25 ± 1.51 %, respectively). It is concluded that grazing at high densities of L. leucocephala affects daily weight gain of hair sheep, possibly due to ingestion of high amounts of mimosine which may exert an adverse effect on voluntary intake. PMID:22528536

Barros-Rodríguez, Marcos; Solorio-Sánchez, Javier; Ku-Vera, Juan; Ayala-Burgos, Armín; Sandoval-Castro, Carlos; Solís-Pérez, Georgina

2012-12-01

216

The influence of stocking rate and grazing system on the crude protein content and digestibility of Tarchonanthus veld in the northern cape  

Microsoft Academic Search

Four stocking rates (10, 7, 6 and 4 ha\\/large stock unit), in both rotational and continuous grazing, have been applied with cattle on Tarchonanthus veld. The crude protein content and digestibility of organic matter of handcut samples and herbage samples collected by means of oesophageal fistulated steers in the different treatments, were determined.The results indicated that the crude protein content

J H Fourie; E A N Engels; Heila L H C DeBruyn

1986-01-01

217

[Importance of herd management in loose housing systems in the social behavior of dairy cows].  

PubMed

In five loose housed dairy herds three different kinds of herd management were tested in two variants with respect to frequencies of agonistic social behaviour. Treatments were (1) a short (0.5 h) and a long (3 h) fixation time in the feeding rack, (2) single and group (3 animals) introduction of new heifers into the herd and (3) an open and a closed outdoor yard during nighttime. The investigated agonistic behaviour patterns were: pushing and chasing. The herds were observed in the evening after milking during one four-hour period starting one hour after opening the feeding rack when testing treatment (3) and immediately after opening the feeding rack when testing treatment (1) and (2). Statistical analysis were carried out with the Wilcoxon signed-ranks test for matched samples. Effects of fixation time differed inconsistently and were not significant. In 3 out of 5 farms the frequency of agonistic behaviour was lower, when cows were restrained 3 h in the feeding rack compared to 0.5 h. In two of these 3 herds, the animals had the possibility to drink water from bowls directly at the feeding rack, in the third herd the food was silage which has a higher water content. Therefore in these herds, the agonistic interactions at the drinking facility in the stable after opening the feeding rack was low. Contrary, in the two other herds, with dry feed (hay) and no drinking bowls at the feeding rack, frequency of agonistic behaviour was higher after the long restraint which might be due to higher competition at the drinking facilities. Agonistic interactions per cow as well as per new introduced heifer were lower (p < or = 0.05) when only a single heifer was introduced to the herd compared to the introduction of a group of 3 heifers. The frequency of agonistic social behaviour of horned dairy cows that had access to a yard at night was significantly lower compared to the situation when the yard was closed over night (p < or = 0.05). This may be due to the higher space allowances per cow but also to the additional structuring of the locomotion area. PMID:10954997

Menke, C; Waiblinger, S; Fölsch, D W

2000-07-01

218

Effects of two stall flooring systems on the behaviour of tied dairy cows.  

PubMed

Effects on dairy cow behaviour of a new type of flooring in tie-stalls, with the ability to drain faeces and urine, was studied in a controlled randomised trial in one Swedish university herd. Forty-two Swedish Red and White cows were kept tied in traditional long-stalls (2.20m). In 21 stalls (one stall row), the rearmost 0.74m of the solid stall floor had been replaced with nine rubber-coated 53mm wide slats, divided by 29mm slots. Stalls with rubber slats were equipped with 20mm ethyl-vinyl-acetate (EVA) mats in the front part and littered with 0.7kg of wood shavings daily, while stalls with a solid floor had standard rubber mats and received 3kg of chopped straw daily as bedding. Behaviour was compared between the two stall types, using video recordings of 12 matched pairs of cows for two complete 24h periods each. Statistical analysis was done using the Student's t-test for matched pairs or the sign test. Cows on the rubber slatted flooring lie down and rise normally and without any increased risk of slipping. They lay down more comfortably, i.e. spent on an average 23% less time preparing to lie down, and slipped less frequently during rising. There was some evidence of a preference for a solid floor when lying. PMID:11376835

Hultgren, J

2001-08-01

219

Constraints on smallholder market oriented dairy systems in the north eastern coastal region of Tanzania.  

PubMed

Twenty five smallholder dairy farmers and other stakeholders, through a Participatory Rural Appraisal in three wards of the Tanga township of north east coastal Tanzania, ranked their perceived constraints in descending order of importance: Low milk price and marketing, feed shortage in the dry season, poor management, low animal productivity, poor reproductive performance and diseases. Tick borne diseases were reported on a majority of farms. An Economic Opportunity Survey revealed wide ranges in management indices and improvement in annual milk production, age at first calving and lactation length to represent the best potential for gain. Performance generally was below locally set targets. Farmers spent on average in the three wards between 39% and 77% of income from milk on feed costs yearly. Interventions were instituted emphasising those that farmers could afford immediately. They included farmer training, dry season feed supplementation, tick control, improvement of animal shed/ house cleanliness and the formation of a cooperative for milk marketing. Partial budgeting is being used to monitor success. Follow-up meetings and regular visits to farms by field officers are disseminating information on outcomes to encourage farmers to continue with interventions and spread useful knowledge to friends and neighbours. PMID:18265872

Nkya, R; Kessy, B M; Lyimo, Z C; Msangi, B S J; Turuka, F; Mtenga, K

2007-12-01

220

Dairy: Outlook and Situation.  

National Technical Information Service (NTIS)

Record milk production, alltime-high Government purchases despite improved commercial disappearance and milk and dairy product prices near year earlier levels highlight the 1982 dairy situation. Potentially, 1983 presents the same picture. Farm prices are...

1982-01-01

221

The Effect of Carbohydrate Source on Nitrogen Capture in Dairy Cows on Pasture1  

Microsoft Academic Search

The objectiveof this studywas to determineif feeding carbohydrate supplements with faster degradation rates than corn to dairy cows grazing ryegrass would improve nitrogen capture, milk production, and compo- nents. Treatments were grain supplements based on: 1) corn (CORN), 2) barley and molasses (BM), or 3) citrus pulp and molasses (CM). For BM and CM, the diet composition was the same

A. M. Gehman; J. A. Bertrand; T. C. Jenkins; B. W. Pinkerton

2006-01-01

222

Vegetation development influenced by grazing in the coastal dunes near The Hague, The Netherlands  

Microsoft Academic Search

In 1990, grazing was introduced in a section of Meijendel, a coastal sand dune system near The Hague, The Netherlands. After\\u000a five years an evaluation was made of the effects of grazing on vegetation development. Three transects were established, two\\u000a in grazed areas and one in an ungrazed area. Field survey data were classified by means of TWIN-SPAN, ordinated with

A. J. de Bonte; A. Boosten; H. G. J. M. van der Hagen; K. V. Sýkora

1999-01-01

223

The relationship among current management systems, production, disease and drug usage on Ontario dairy farms.  

PubMed

The study involved 110 randomly selected dairy farms located in the Ontario, Canada counties of Bruce, Grey, Huron, Oxford, Perth, Waterloo and Wellington. Herds were classified as "intensive" and "extensive". On extensive farms, data were collected at the herd level only, while on intensive farms, data were recorded at both the individual animal and herd level. Data collection continued for approximately two and one-half years. At each visit, technicians collected production data from the most recent production recording scheme report and from the "daily log" maintained by each producer. As well as the ongoing data collection procedures, a number of supplementary data collections were made. The average 305 day milk production increased gradually during the three calendar years from 6224.6 kg in 1981 to 6443.7 kg in 1983. The average calving interval was stable at 13.2 months for all three years. The majority of cows removed from the herds were culled for beef (0.243 per animal year). The next highest removal rate was for domestic sale, followed by death, export sale and destroyed. The highest disease rate, for those conditions whose rates were based on calving, was for retained placenta (0.09 per calving), while clinical mastitis was highest for those conditions whose rates were based on animal years (0.37 per animal year). The overall crude antimicrobial dosage rate, that is, including any antimicrobial used for either prophylactic or therapeutic purposes, was 3.85 doses per animal year. The rate for therapeutic purposes only was 3.6 doses per animal year. Penicillin/streptomycin was used most often with a rate of 1.45 doses per animal year. PMID:3742360

Meek, A H; Martin, S W; Stone, J B; McMillan, I; Britney, J B; Grieve, D G

1986-01-01

224

The relationship among current management systems, production, disease and drug usage on Ontario dairy farms.  

PubMed Central

The study involved 110 randomly selected dairy farms located in the Ontario, Canada counties of Bruce, Grey, Huron, Oxford, Perth, Waterloo and Wellington. Herds were classified as "intensive" and "extensive". On extensive farms, data were collected at the herd level only, while on intensive farms, data were recorded at both the individual animal and herd level. Data collection continued for approximately two and one-half years. At each visit, technicians collected production data from the most recent production recording scheme report and from the "daily log" maintained by each producer. As well as the ongoing data collection procedures, a number of supplementary data collections were made. The average 305 day milk production increased gradually during the three calendar years from 6224.6 kg in 1981 to 6443.7 kg in 1983. The average calving interval was stable at 13.2 months for all three years. The majority of cows removed from the herds were culled for beef (0.243 per animal year). The next highest removal rate was for domestic sale, followed by death, export sale and destroyed. The highest disease rate, for those conditions whose rates were based on calving, was for retained placenta (0.09 per calving), while clinical mastitis was highest for those conditions whose rates were based on animal years (0.37 per animal year). The overall crude antimicrobial dosage rate, that is, including any antimicrobial used for either prophylactic or therapeutic purposes, was 3.85 doses per animal year. The rate for therapeutic purposes only was 3.6 doses per animal year. Penicillin/streptomycin was used most often with a rate of 1.45 doses per animal year.

Meek, A H; Martin, S W; Stone, J B; McMillan, I; Britney, J B; Grieve, D G

1986-01-01

225

First description of milk flow traits in Tunisian dairy dromedary camels under an intensive farming system.  

PubMed

In order to evaluate milking ability in dromedary camels, 124 milk flow curves were registered during morning milking of 20 dairy Maghrebi dromedary camels. Animals were in lactations 1-8, were 6-19 years old and were 4-15 months of their current lactation. Milk flow curves were recorded using an electronic milk flow meter (Lactocorder®). Milk flow curves were classified in three typical patterns: type 1 represents curves with one high and short peak of milk flow; type 2 represents curves with a moderate mean milk flow rate during a large plateau phase; and type 3 represents curves with lower mean milk flow rate and a relatively longer milking duration. The ratio of the different milk flow patterns in the population evaluated was 40:38:22% for types 1, 2 and 3, respectively. The highest milk yield per milking, average and peak milk flow were observed in camels with type 1 curves (4·24 kg, 1·49 and 3·54 kg/min, respectively) followed by type 2 animals (3·30 kg, 1·12 and 2·12 kg/min, respectively) and lastly type 3 curves (2·34 kg, 0·65 and 1·23 kg/min, respectively). This study confirmed that a major proportion of dromedary camels have a suitable machine milking ability. Nevertheless, our results suggest that pre-stimulation and improving the milking process may improve milking efficiency and guarantee a more complete and rapid emptying of the udder. PMID:24622212

Atigui, Moufida; Hammadi, Mohamed; Barmat, Ahmed; Farhat, Mohamed; Khorchani, Touhami; Marnet, Pierre-Guy

2014-05-01

226

Effect of sea cucumber (Australostichopus mollis) grazing on coastal sediments impacted by mussel farm deposition.  

PubMed

Deposit-feeding holothurians are important processors of surface sediments in many coastal marine systems. The present study examined the effect of grazing by the sea cucumber Australostichopus mollis on sediment impacted by green-lipped mussel biodeposits (faeces and pseudofaeces) from coastal aquaculture activities. Grazing effects were investigated in a series of tank-based feeding experiments conducted over 1, 2, 4 and 8 week periods. Sediment quality indicators routinely applied to determine the impacts of coastal aquaculture were used to evaluate sediment health from grazed and ungrazed sediments. Sea cucumber grazing resulted in reductions in total organic carbon, chlorophyll a and phaeopigment, as well as chlorophyll a/phaeopigment ratio of impacted sediments. These results demonstrate that sea cucumber grazing significantly reduces the accumulation of both organic carbon and phytopigments associated with biodeposition from mussel farms. Sea cucumber grazing offers a means of constraining or reversing the pollutive impacts of coastal bivalve aquaculture. PMID:19428032

Slater, Matthew J; Carton, Alexander G

2009-08-01

227

SUPPORTING SMALLHOLDER DAIRYING IN ASIA  

Microsoft Academic Search

Tropical Asia is the largest milk-producing region of the world. Its efficiency as an integrated smallholder production system provides financial, health and social benefits to millions of rural dwellers. Variations between cultures and economic circumstances define local options for further development of smallholder dairying. Notwithstanding the success of this industry, it has been misunderstood in some international development agencies and

L. Falvey; C. Chantalakhana

228

Indicators of grazing impact in Inner Mongolian steppe ecosystems  

NASA Astrophysics Data System (ADS)

The DFG research group 536 MAGIM (Matter fluxes in grasslands of Inner Mongolia as influenced by stocking rate) investigates the influence of grazing intensity on matter and water cycles in grazed steppe ecosystems of Inner Mongolia. This Sino-German co-operation applies an interdisciplinary approach to investigate major ecosystem functions and how they are affected by grazing and overgrazing. Within the research group an indicator system is developed to systemize the feedback of ecosystem parameters to the influence of grazing and to analyse, which parameter or parameter group reacts most sensitively. Parameters were measured at up to five different grazing intensities (from ungrazed to heavy grazed) and are related to four thematic indicator groups (plant productivity, atmosphere, pedosphere, hydrosphere). The parameters were scaled to allow assessing the influence of grazing intensity between different sets of parameters. For this the average value of a parameter at the lowest grazing intensity (ungrazed) was set 100%, so that the values at the other intensities could be scaled scaled adequately. Then the difference between highest and lowest grazing intensity was determined. According to this difference the influence of grazing was characterized as weak (< 20% difference), medium (20-40%), strong (40-60%) and very strong (> 60%). Impact of grazing on the parameters will be marked as weak (w), medium (m), strong (s) and very strong (vs) in the text. The group plant productivity includes the vegetation parameters aboveground biomass and belowground biomass. Belowground biomass (s) was significantly different between grazing treatments with the highest value at the ungrazed site (399.00 g m-2 a-1) and the lowest at the heavy grazed site (208.00 g m-2 a-1). Aboveground biomass (m) ranged between 91.33-131.67 g m-2 a-1 and differed significantly between the ungrazed and the heavy grazed site, again with higher values at the ungrazed site (Gao et al. 2008). The group atmosphere consists of micrometeorological parameters, dust flux and deposition as measure of erosive processes and trace gas fluxes. Available energy and soil temperature were always significantly different between two simultaneously measured grazing intensities. Available energy was higher at the ungrazed site in all years measured (mean difference of about 19 W m-2). Soil temperature was lower at the ungrazed site (Ketzer et al. 2008). Dust deposition is important for the C and N balance in semi-arid grasslands and was investigated during the dust storm period from March to May. The largest matter deposition of C (vs) and N (vs) was measured at the ungrazed site with 328.7 (mg Corg m-2 d-1) and 30.30 (mg Nt m-2 d-1) on average. Heavy grazing resulted in average organic carbon and nitrogen deposition of 106.67 (mg Corg m-2 d-1) and 9.8 (mg N m-2 d-1) in average (Hoffmann et al. 2008). Wind driven soil deposition and erosion were influenced heavily by grazing. The critical vegetation cover is about 20-30%, at which net soil losses occur. No significant differences in N trace gas fluxes were found between plots. Mean values of N2O fluxes (s) varied between 0.39 and 1.60 ?g N2O-N m-2 h-1 (Holst et al. 2007). During all measuring periods, significantly lower mean soil CH4 uptake at moderate grazing (28 mg C m-2 h-1) as compared to ungrazed (56 ?g C m-2 h-1) was found (Liu et al. 2007). The pedosphere indicator group includes soil chemical, soil physical and microbiological parameters. Organic carbon (s) and total N (s) concentrations decreased significantly with increasing grazing intensity. No effect of grazing on pH (w) or soil C/N ratio (w) was detected. Bulk density (m) significantly increased with increasing grazing intensity, from 0.94 g cm-3 at the ungrazed site to 1.28 g cm-3 at the heavily grazed site (Steffens et al. 2008). Also shear strength (m) increased with increasing grazing intensity (Zhao et al. 2007). Gross rates of N mineralization (vs) and nitrification (vs) determined at in situ soil moisture and soil temperature conditions were i

Blank, B.; Breuer, L.; Butterbach-Bahl, K.; Frede, H.-G.

2009-04-01

229

Study of focused-ion-beam-induced structural and compositional modifications in nanoscale bilayer systems by combined grazing incidence x ray reflectivity and fluorescence  

SciTech Connect

A detailed analysis of the structural and compositional changes in NiFe/Au bilayers induced by a focused ion beam (FIB) is presented. NiFe/Au bilayers with different thickness were irradiated with a focused 30 keV Ga{sup +} ion beam, and the evaluation of the individual layers and interfaces were investigated systematically as a function of a broad range of irradiation fluence using grazing incidence x ray reflectivity (GIXRR) and angular dependent x ray fluorescence (ADXRF) techniques carried out at synchrotron radiation sources. Experimental data were collected from 1.3 mm x 4.5 mm structures, and irradiation of such a broad areas with a 100-nm-wide focused ion beam is a challenging task. Two irradiation regimes were identified: For Ga{sup +} fluences < 15.6 x 10{sup 14} ion/cm{sup 2} (low dose regime), the main influence of the focused ion beam is on the interface and, beyond this dose (high dose regime), sputtering effects and ion implantation becomes significant, eventually causing amorphization of the bilayer system. The broadening of the NiFe/Au interface occurs even at the lowest dose, and above a critical fluence ({Phi} = 1.56 x 10{sup 14} ion/cm{sup 2}) can be represented by an interfacial-intermixed layer (Ni{sub x}Fe{sub y}Au{sub (1-x-y)}; x = 0.5-0.6, y 0.1-0.15) formed between the NiFe and Au layers. The thickness of this layer increases with irradiation fluence in the low dose regime. A linear relationship is found between the squared intermixing length and irradiation fluence, indicating that FIB-induced mixing is diffusion controlled. The ballistic model fails to describe FIB-induced intermixing, indicating that thermodynamical factors, which might be originated from FIB specific features, should be taken into account. Despite the complexity of the chemical and structural formation, good agreement between the experiment and theory highlights the functionality of the combined GIXRR and ADXRF techniques for studying intermixing in high resolution.

Arac, Erhan; Burn, David M.; Eastwood, David S.; Atkinson, Del [Department of Physics, Durham University, Durham DH1 3LE (United Kingdom); Hase, Thomas P. A. [Department of Physics, University of Warwick, Coventry CV4 7AL (United Kingdom)

2012-02-15

230

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)

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.

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

2013-12-01

231

The use of rose bengal plate test to asses cattle exposure to Brucella infection in traditional and smallholder dairy production systems of tanga region of Tanzania.  

PubMed

A cross-sectional epidemiological study was conducted to determine the seroprevalence and to identify risk factors for bovine brucellosis seropositivity in traditional and smallholder dairy cattle production systems in the Tanga region of North-eastern Tanzania. The study populations comprised 246 indigenous and 409 crossbred cattle, randomly selected from 105 smallholder dairy and 25 traditional managed herds, respectively. Individual animal and herd-level data were collected using a structured questionnaire. Serum samples were screened for Brucella antibodies using the Rose Bengal Plate Test The overall seroprevalence of Brucella antibodies in the smallholder dairy and traditional managed cattle was 4.1% and 7.3% respectively. The corresponding overall herd prevalence was 10.5% and 20% respectively. Using multivariate logistic regression analysis, closeness to stock route, access to surface drinking water and location were identified as the major risk factors for individual herd seroprevalence. Older animals (?6 years) were associated with increased risk of sero-positivity compared to animals of age category of ?6 years. The results showed that brucellosis is prevalent and widely distributed locally, underscoring the need for further studies including surveillance and institution of preventive and control measures particularly among female young-stock and the general public who are at high risk of contracting brucellosis. PMID:20953382

Swai, Emanuel Senyael; Schoonman, Luuk

2010-01-01

232

Computing the Grazing Angle of Specular Reflection.  

National Technical Information Service (NTIS)

Three methods are given for computing the grazing angle of specular reflection. The first gives an approximation to the grazing angle. The second is an iterative method, whose derivation is easy and provides for the computation of the grazing angle to any...

A. Miller E. Vegh

1982-01-01

233

Dairy: World Markets and Trade, August 1994.  

National Technical Information Service (NTIS)

Contents: Dairy: World Markets and Trade; Dairy Production in Selected Countries; Dairy Trade in Selected Countries; Selected Exporters; Selected Importers; Milk and Dairy Products Production, Supply, and Demand Tables; World Dairy Prices; FY 1994 GSM-102...

1994-01-01

234

Dairy: World Markets and Trade, March 1994.  

National Technical Information Service (NTIS)

Contents: Dairy Production and Trade in Selected Countries; Milk and Dairy Products Production, Supply, and Demand Tables: Fluid Milk, Butter, Cheese, Nonfat Dry Milk, Casein, Whole Milk Powder; Uruguay Round: Dairy; World Dairy Prices; Dairy Export Incen...

1994-01-01

235

Simulation of grazing-incidence coherent imaging  

SciTech Connect

A method is proposed for simulating optical object images formed by oblique or grazing-incidence coherent beams. The theoretical approach relies on the solution of a parabolic equation, which generalises the Fresnel integral. Our numerical results are given for experimental conditions close to those realised when use is made of modern soft X-ray lasers. The newly developed method may also be employed to simulate X-ray imaging systems developed around synchrotron and free-electron laser beams. (x-ray optics)

Artyukov, I A; Vinogradov, Aleksandr V; Popov, N L; Seleznev, V N

2012-02-28

236

From rags to riches: the story of carbon, nutrients and pasture with dairy compost application  

NASA Astrophysics Data System (ADS)

Around the world, dairy farmers are transforming dairy waste to compost for land application. In southeastern Australia, farmers are using composted dairy waste to increase production and reduce costs. In addition, the farmers are considering the benefits of compost for increasing sequestration of soil carbon, and on-farm nutrient retention. The "Carbon Farming Initative" in Australia is exploring the option to allow farmers to trade Carbon Credits for carbon stored in the soil. Compost also retains vital nutrients, such as N, on farm rather than importing N in the form of mineral fertilisers. Composting also reduces greenhouse gas emissions, such as CH4, compared to when stored in effluent ponds. This project will investigate if dairy compost applied to pasture improves carbon sequestration, nutrient retention and pasture production. In this project dairy compost, made from dairy effluent, feedpad waste, spoilt sillage and wood mulch, was applied onto a 1Ha field and companion plots at a rate of 0, 3, 6 and 12 t/ha. The field plot is open to grazing and normal farm management practices. The companion plots are being subjected to simulated grazing (mowing). The trials, currently underway will run for 18 months. Along with preliminary soil carbon results, this work will also include preliminary data for total and plant available nutrients, and farm biomass production. The outcomes of this research, and benefits it finds for "Carbon Farming" and nutrient retention has practical, policy and economic applications for world wide markets.

Drake, Jess; Cavagnaro, Tim; Patti, Tony; Wilkinson, Kevin; McDonald, Declan; Johnston, Priscilla; Wilson, Katrina; Rose, Mick; Jackson, Roy

2014-05-01

237

Adaptation of a grazing gradient concept to heterogeneous Mediterranean rangelands using cost surface modelling  

Microsoft Academic Search

Livestock grazing has been an important factor in shaping Mediterranean rangelands. Despite their long history of utilisation, recent changes in socio-economic frameworks and the intensification of grazing systems have frequently caused rangeland ecosystems to depart from equilibrium states and initiated degradation processes. Remote sensing allows quantifying temporal and spatial trends of vegetation cover as an indirect indicator of land degradation.

A. Röder; T. Kuemmerle; J. Hill; V. P. Papanastasis; G. M. Tsiourlis

2007-01-01

238

Determining grazing capacity in Namibia with the aid of remote sensing  

Microsoft Academic Search

The Namibian rangelands consist of a mixture of herbaceous and woody components. The main source of income is from farming systems with grass production the predominant source of forage. For rangeland managers to utilise this source sustainably, the accurate determination of grazing capacity is vital since it allows for adapting the animal load, and therefore the grazing pressure, to the

C. Espach; L. G. Lubbe; N. Ganzin

2009-01-01

239

Assessing agro-environmental performance of dairy farms in northwest Italy based on aggregated results from indicators.  

PubMed

Dairy farms control an important share of the agricultural area of Northern Italy. Zero grazing, large maize-cropped areas, high stocking densities, and high milk production make them intensive and prone to impact the environment. Currently, few published studies have proposed indicator sets able to describe the entire dairy farm system and their internal components. This work had four aims: i) to propose a list of agro-environmental indicators to assess dairy farms; ii) to understand which indicators classify farms best; iii) to evaluate the dairy farms based on the proposed indicator list; iv) to link farmer decisions to the consequent environmental pressures. Forty agro-environmental indicators selected for this study are described. Northern Italy dairy systems were analysed considering both farmer decision indicators (farm management) and the resulting pressure indicators that demonstrate environmental stress on the entire farming system, and its components: cropping system, livestock system, and milk production. The correlations among single indicators identified redundant indicators. Principal Components Analysis distinguished which indicators provided meaningful information about each pressure indicator group. Analysis of the communalities and the correlations among indicators identified those that best represented farm variability: Farm Gate N Balance, Greenhouse Gas Emission, and Net Energy of the farm system; Net Energy and Gross P Balance of the cropping system component; Energy Use Efficiency and Purchased Feed N Input of the livestock system component; N Eco-Efficiency of the milk production component. Farm evaluation, based on the complete list of selected indicators demonstrated organic farming resulted in uniformly high values, while farms with low milk-producing herds resulted in uniformly low values. Yet on other farms, the environmental quality varied greatly when different groups of pressure indicators were considered, which highlighted the importance of expanding environmental analysis to effects within the farm. Statistical analysis demonstrated positive correlations between all farmer decision and pressure group indicators. Consumption of mineral fertiliser and pesticide negatively influenced the cropping system. Furthermore, stocking rate was found to correlate positively with the milk production component and negatively with the farm system. This study provides baseline references for ex ante policy evaluation, and monitoring tools for analysis both in itinere and ex post environment policy implementation. PMID:24747935

Gaudino, Stefano; Goia, Irene; Grignani, Carlo; Monaco, Stefano; Sacco, Dario

2014-07-01

240

Participatory modeling in dairy farm systems: a method for building consensual environmental sustainability using seasonal climate forecasts  

Microsoft Academic Search

Dairy farmers face increasing pressure to decrease environmental impact while remaining economically viable. Adaptation of farm management practices in response to seasonal climate forecasts may be one means of achieving these objectives. This paper describes the interactive and iterative process by which farmers, researchers, extension agents, regulatory agencies, and other stakeholders collaborated to create, calibrate, and validate the Dynamic North

Victor E. Cabrera; Norman E. Breuer; Peter E. Hildebrand

2007-01-01

241

Effect of production system and farming strategy on greenhouse gas emissions from commercial dairy farms in a life cycle approach  

Microsoft Academic Search

This paper documents and illustrates a model to estimate the greenhouse gas (GHG) emissions and land use on commercial dairy farms. Furthermore, a method of allocating total farm emissions into meat and milk products was developed and, finally, potential mitigation options at farm scale were identified. The GHG emission at farm gate using a Life Cycle Approach (LCA) was estimated

Troels Kristensen; Lisbeth Mogensen; Marie Trydeman Knudsen; John E. Hermansen

2011-01-01

242

Milk Conjugated Linoleic Acid Response to Fish Oil and Sunflower Oil Supplementation to Dairy Cows Managed Under Two Feeding Systems  

Microsoft Academic Search

Earlier research showed that conjugated linoleic acid (CLA) content in milk fat is highest when cows' diets are supplemented with a blend of fish oil (FO) and linoleic acid-rich oils. The objective of this study was to compare the effect of FO and sunflower oil (SFO) supplementation on milk cis-9, trans-11 CLA when dairy cows managed on pasture or in

A. A. AbuGhazaleh; D. O. Felton; S. A. Ibrahim

2007-01-01

243

Cooling Dairy Cattle by a Combination of Sprinkling and Forced Ventilation and Its Implementation in the Shelter System  

Microsoft Academic Search

A method for cooling dairy cattle based on repeated wetting to attain maximal water trapping in the coat, fol- lowed by its rapid evaporation by using forced ventilation has been examined. Effects examined include duration of wetting, duration of cooling, and density of the animals in the holding area. The coat was wetted by inverted static sprin- klers. Also examined

I. Flamenbaum; D. Wolfenson; M. Mamen; A. Berman

1986-01-01

244

Persistent, toxin-antitoxin system-independent, tetracycline resistance-encoding plasmid from a dairy Enterococcus faecium isolate.  

PubMed

A tetracycline-resistant (Tet(r)) dairy Enterococcus faecium isolate designated M7M2 was found to carry both tet(M) and tet(L) genes on a 19.6-kb plasmid. After consecutive transfer in the absence of tetracycline, the resistance-encoding plasmid persisted in 99% of the progenies. DNA sequence analysis revealed that the 19.6-kb plasmid contained 28 open reading frames (ORFs), including a tet(M)-tet(L)-mob gene cluster, as well as a 10.6-kb backbone highly homologous (99.9%) to the reported plasmid pRE25, but without an identified toxin-antitoxin (TA) plasmid stabilization system. The derived backbone plasmid without the Tet(r) determinants exhibited a 100% retention rate in the presence of acridine orange, suggesting the presence of a TA-independent plasmid stabilization mechanism, with its impact on the persistence of a broad spectrum of resistance-encoding traits still to be elucidated. The tet(M)-tet(L) gene cluster from M7M2 was functional and transmissible and led to acquired resistance in Enterococcus faecalis OG1RF by electroporation and in Streptococcus mutans UA159 by natural transformation. Southern hybridization showed that both the tet(M) and tet(L) genes were integrated into the chromosome of S. mutans UA159, while the whole plasmid was transferred to and retained in E. faecalis OG1RF. Quantitative real-time reverse transcription-PCR (RT-PCR) indicated tetracycline-induced transcription of both the tet(M) and tet(L) genes of pM7M2. The results indicated that multiple mechanisms might have contributed to the persistence of antibiotic resistance-encoding genes and that the plasmids pM7M2, pIP816, and pRE25 are likely correlated evolutionarily. PMID:21784909

Li, Xinhui; Alvarez, Valente; Harper, Willis James; Wang, Hua H

2011-10-01

245

Impact evaluation of a refrigeration control system installed at Vitamilk Dairy, Incorporated under the Energy $avings Plan  

SciTech Connect

This impact evaluation of a refrigeration control system (RCS) recently installed at Vitamilk Dairy, Inc. (Vitamilk) was conducted for the Bonneville Power Administration (Bonneville) as part of an evaluation of its Energy $avings Plan (E$P) Program. The RCS installation at Vitamilk uses microcomputer- based controls to automate refrigeration equipment previously controlled manually. This impact evaluation assessed how much electricity is being saved at Vitamilk as a result of the E$P and to determine how much the savings cost Bonneville and the region. On a unit savings basis, this project will save 9.7 kWh/tonne (8-8 kWh/ton) of milk and ice cream produced, based on the product mix for June 1992 through May 1993, representing a 28% reduction in energy consumption. The project was installed in 1992 for a total cost of $129,330, and Vitamilk received payment of $62,974 from Bonneville in 1993 for the acquisition of energy savings. The real levelized cost of these energy savings to Bonneville is 8.5 mills/kWh (in 1993 dollars) over the project`s assumed 15-year life, and the real levelized cost to the region is 17.9 mills/kWh (in 1993 dollars), not including transmission and distribution effects. Based on the expected project installation costs and energy savings benefits, the RCS would not have been implemented by Vitamilk without the E$P acquisition payment. The expected acquisition payment reduced the estimated payback period from 7.0 to 2.8 years. Although Vitamilk would generally require an energy conservation project to have a payback period of two years or less, the slightly longer payback period was accepted in this case.

Brown, D.R.; Dixon, D.R.; Spanner, G.E.

1995-01-01

246

Expanding the dairy herd in pasture-based systems: the role for sexed semen use on virgin heifers.  

PubMed

A model was developed to examine the effects of sexed semen use on replacement heifer numbers and rate of herd expansion in a seasonal dairy production system. Three separate herds were established according to the type of semen used on virgin heifers: conventional frozen-thawed (Conv), sexed fresh (SFre), or sexed frozen-thawed (SFro). In the model, sexed semen was used for the first and second inseminations in heifers only. Pregnancy rates achieved with sexed fresh and sexed frozen-thawed semen were assumed to be 94% and 75% of those achieved with conventional frozen-thawed semen, respectively. Initial herd size was 100 cows, which was maintained for the first 2 yr of the 15-yr simulation, after which all available replacement heifers were retained to facilitate herd expansion. Two different scenarios of land availability (S1 and S2) were examined for each of the 3 herds using different semen types: land available allowed expansion to a maximum herd size of 150 cows (S1) or 300 cows (S2). Once maximum herd size was reached, sexed semen use was discontinued and all excess heifer calves were sold at 1 mo of age. All capital expenditure associated with expansion was financed with a 15-yr loan. Each of the different options was evaluated in terms of annual farm profit, annual cash flow, and total discounted net profit. The analysis was completed at a milk price of € 0.27/L, and sensitivity around milk price was carried out at € 0.22/L and € 0.32/L. The use of SFre generated more replacement heifers and thus faster herd expansion compared with SFro and Conv semen. Maximum herd size was reached in yr 5, 6, and 7 under S1, and in yr 10, 12, and 14 under S2 for SFre, SFro, and Conv herds, respectively. Total discounted net profit under S1 for the SFre herd was € 19,929 greater than that of the SFro herd and € 41,852 greater than that of the Conv herd. Under S2, discounted net profit for the SFre herd was € 138,587 greater than that of the SFro herd and € 239,987 greater than that of the Conv herd. All 3 herds suffered negative cash flows for extended periods under both S1 and S2 at the lower milk price of € 0.22/L, although cash flows were most negative in the SFre herd. The use of sexed semen, in particular fresh sexed semen, in dairy heifers facilitates faster and more profitable expansion compared with the use of conventional frozen-thawed semen. Financial pressures caused by low milk price were greatest when the rate of expansion was highest. PMID:23200471

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

2013-02-01

247

Aberrations for Grazing Incidence Optics  

NASA Technical Reports Server (NTRS)

Large number of grazing incidence telescope configurations have been designed and studied. Wolte1 telescopes are commonly used in astronomical applications. Wolter telescopes consist of a paraboloidal primary mirror and a hyperboloidal or an ellipsoidal secondary mirror. There are 8 possible combinations of Wolter telescopes. Out of these possible designs only type 1 and type 2 telescopes are widely used. Type 1 telescope is typically used for x-ray applications and type 2 telescopes are used for EUV applications. Wolter-Schwarzshild (WS) telescopes offer improved image quality over a small field of view. The WS designs are stigmatic and free of third order coma and, therefore, the PSF is significantly better over a small field of view. Typically the image is more symmetric about its centroid. As for the Wolter telescopes there are 8 possible combinations of WS telescopes. These designs have not been widely used because the surface equations are complex parametric equations complicating the analysis and typically the resolution requirements are too low to take full advantage of the WS designs. There are several other design options. Most notable are wide field x-ray telescope designs. Polynomial designs were originally suggested by Burrows4 and hyperboloid-hyperboloid designs for solar physics applications were designed by Harvey5. No general aberration theory exists for grazing incidence telescopes that would cover all the design options. Several authors have studied the aberrations of grazing incidence telescopes. A comprehensive theory of Wolter type 1 and 2 telescopes has been developed. Later this theory was expanded to include all possible combinations of grazing incidence and also normal incidence paraboloid-hyperboloid and paraboloid-ellipsoid telescopes. In this article the aberration theory of Wolter type telescopes is briefly reviewed.

Saha, Timo T.

2008-01-01

248

Relative importance of management, meteorological and environmental factors in the spatial distribution of Fasciola hepatica in dairy cattle in a temperate climate zone.  

PubMed

Fasciola hepatica, a trematode parasite with a worldwide distribution, is the cause of important production losses in the dairy industry. Diagnosis is hampered by the fact that the infection is mostly subclinical. To increase awareness and develop regionally adapted control methods, knowledge on the spatial distribution of economically important infection levels is needed. Previous studies modelling the spatial distribution of F. hepatica are mostly based on single cross-sectional samplings and have focussed on climatic and environmental factors, often ignoring management factors. This study investigated the associations between management, climatic and environmental factors affecting the spatial distribution of infection with F. hepatica in dairy herds in a temperate climate zone (Flanders, Belgium) over three consecutive years. A bulk-tank milk antibody ELISA was used to measure F. hepatica infection levels in a random sample of 1762 dairy herds in the autumns of 2006, 2007 and 2008. The infection levels were included in a Geographic Information System together with meteorological, environmental and management parameters. Logistic regression models were used to determine associations between possible risk factors and infection levels. The prevalence and spatial distribution of F. hepatica was relatively stable, with small interannual differences in prevalence and location of clusters. The logistic regression model based on both management and climatic/environmental factors included the factors: annual rainfall, mowing of pastures, proportion of grazed grass in the diet and length of grazing season as significant predictors and described the spatial distribution of F. hepatica better than the model based on climatic/environmental factors only (annual rainfall, elevation and slope, soil type), with an Area Under the Curve of the Receiver Operating Characteristic of 0.68 compared with 0.62. The results indicate that in temperate climate zones without large climatic and environmental variation, management factors affect the spatial distribution of F. hepatica, and should be included in future spatial distribution models. PMID:20887726

Bennema, S C; Ducheyne, E; Vercruysse, J; Claerebout, E; Hendrickx, G; Charlier, J

2011-02-01

249

Soil physical responses to cattle grazing cover crops under conventional and no tillage in the Southern Piedmont USA  

Microsoft Academic Search

Grazing of cover crops in grain cropping systems can increase economic return and diversify agricultural production systems, but the environmental consequences of this intensified management have not been well documented, especially under different tillage systems. We conducted a multiple-year investigation of how cover crop management (grazed and ungrazed) and tillage system [conventional (CT; initial moldboard plowing and thereafter disk tillage)

Alan J. Franzluebbers; John A. Stuedemann

2008-01-01

250

Anaerobic digestion of the liquid fraction of dairy manure  

SciTech Connect

The authors tested several solid liquid separation systems suitable for processing dairy manure prior to anaerobic digestion. None of the systems tried have completely satisfied the requirements. Evaluated effects of separation on biogas production. Unseparated dairy manure produced more biogas than the liquid fraction.

Haugen, V.; Dahlberg, S.; Lindley, J.A.

1983-06-01

251

Grazing animal husbandry based on sustainable nutrient management  

Microsoft Academic Search

Sustainable husbandry systems for grazing animals (cattle and sheep) can be achieved by sustainable nutrient management (SNM). This implies the tuning of inputs to outputs of nutrients, to achieve and maintain optimum ranges of agronomically wanted and ecologically acceptable reserves of single nutrients in the soil. P is presented as the ‘boss cow of the nutrient herd’ and its optimum

C. Hermans; P. H. Vereijken

1995-01-01

252

SIMS DAIRY: A modelling framework to identify sustainable dairy farms in the UK. Framework description and test for organic systems and N fertiliser optimisation  

Microsoft Academic Search

Multiple demands are placed on farming systems today. Society, national legislation and market forces seek what could be seen as conflicting outcomes from our agricultural systems, e.g. food quality, affordable prices, a healthy environmental, consideration of animal welfare, biodiversity etc., Many of these demands, or desirable outcomes, are interrelated, so reaching one goal may often compromise another and, importantly, pose

A. Del Prado; T. Misselbrook; D. Chadwick; A. Hopkins; R. J. Dewhurst; P. Davison; A. Butler; J. J. Schroder; D. Scholefield

2011-01-01

253

MHD models for Sun-grazing comets  

NASA Astrophysics Data System (ADS)

Sun-grazing comets have high orbital eccentricities and low perihelia. They travel between the outer solar system and the lower corona. Recent advances in spacecraft imaging capabilities have enabled us to observe these comets with high resolution both in time and space. These comets exhibit rich tail activity in the lower corona, even multiple tails. Sun-grazing comets interact with the coronal plasma in a very different way, than in the conventional models of comet-solar wind interactions. The parameters, scales, and chemistry are very different. In this study, we have simplified the interaction into two different baseline models. In the first model we show the comet appearance in sub-Alfvenic solar wind. A single-fluid MHD model is applied to comet C2012 S1 (ISON) conditions. In the second model we adopt the chemical reactions with extreme ionization rates around the perihelion of comet C/2011 W3 (Lovejoy). We use our multi-fluid model to track all charge states of oxygen, from O+ to O6+. These steady-state models can be used to explain the chronicle of comet tail appearance as it approaches perihelion.

Jia, Ying-Dong; Shou, Yin-Si; Russell, Christopher T.; Combi, Michael R.; Hansen, Kenneth C.

2014-05-01

254

Grazing season and forage type influence goat milk composition and rennet coagulation properties.  

PubMed

Two different types of pasture (cultivated and rangeland) and 2 different hay qualities (high and low quality) were examined for their effects on goat milk composition and rennet coagulation properties. Furthermore, the effect of dietary treatments in both the early and late grazing season was studied. As lactation stage is known to influence milk composition, the goats in the early and late grazing season were in the same lactation stage at the start of the experiment. The milk composition was influenced both by dietary treatment and season. Milk from goats on pasture was superior to those on hay by containing a higher content of protein and casein, and the goats on cultivated pasture had the highest milk yield. Casein composition was significantly influenced by forage treatment. Goats grazing on cultivated pasture had higher contents of ?s1-casein and also of ?-casein compared with the other treatments, whereas goats grazing on rangeland had the highest content of ?-casein. Factors such as milk yield, casein micelle size, ?s2-casein, and calcium content were reduced in late compared with early season. More favorable rennet coagulation properties were achieved in milk from the early grazing season, with shorter firming time and higher curd firmness compared with milk from the late grazing season, but the firming time and curd firmness were not prominently influenced by forage treatment. The content of ?s2-casein and calcium in the milk affected the firming time and the curd firmness positively. The influence of season and forage treatment on especially milk yield, casein content, and rennet coagulation properties is of economic importance for both the dairy industry and goat milk farmers. PMID:24704223

Inglingstad, R A; Steinshamn, H; Dagnachew, B S; Valenti, B; Criscione, A; Rukke, E O; Devold, T G; Skeie, S B; Vegarud, G E

2014-06-01

255

Multisensor sampling of pelagic ecosystem variables in a coastal environment to estimate zooplankton grazing impact  

NASA Astrophysics Data System (ADS)

Sampling was conducted on the west Florida continental shelf ecosystem modeling site to estimate zooplankton grazing impact on primary production. Samples were collected with the high-resolution sampler, a towed array bearing electronic and optical sensors operating in tandem with a paired net/bottle verification system. A close biological-physical coupling was observed, with three main plankton communities: 1. a high-density inshore community dominated by larvaceans coincident with a salinity gradient; 2. a low-density offshore community dominated by small calanoid copepods coincident with the warm mixed layer; and 3. a high-density offshore community dominated by small poecilostomatoid and cyclopoid copepods and ostracods coincident with cooler, sub-pycnocline oceanic water. Both high-density communities were associated with relatively turbid water. Applying available grazing rates from the literature to our abundance data, grazing pressure mirrored the above bio-physical pattern, with the offshore sub-pycnocline community contributing ˜65% of grazing pressure despite representing only 19% of the total volume of the transect. This suggests that grazing pressure is highly localized, emphasizing the importance of high-resolution sampling to better understand plankton dynamics. A comparison of our grazing rate estimates with primary production estimates suggests that mesozooplankton do not control the fate of phytoplankton over much of the area studied (<5% grazing of daily primary production), but "hot spots" (˜25-50% grazing) do occur which may have an effect on floral composition.

Sutton, Tracey; Hopkins, Thomas; Remsen, Andrew; Burghart, Scott

2001-01-01

256

Technical note: a simple model to estimate changes in dietary composition of strip-grazed cattle during progressive pasture defoliations.  

PubMed

Methodological problems occur in measuring herbage intake and diet quality during short-term (4-24h) progressive defoliations by grazing. Several models were developed to describe pasture component selection by grazing ruminants, particularly sheep. These models contain empirical coefficients to determine preferences that require laborious and data-demanding calibration. The objective was to develop a simple and practical model of changes in diet composition (green:dead) of pastures strip-grazed by dairy cows. The model was based on 3 premises when cows are strip-grazed in relatively homogeneous swards: 1) cows eat dead material only when green leaf and uncontaminated material have been removed; 2) dead material increases toward the bottom of the sward canopy; and 3) cows progressively defoliate pasture in layers. The main simplification in this model was assuming a linear decrease of green mass from the top to the bottom of the sward canopy. Thus, the proportion of green mass in the stratum eaten depended on the proportion of green in the entire sward canopy and its vertical profile. The model offers a simple solution to estimate changes in dietary compositions in pastures strip-grazed by dairy cattle during progressive pasture defoliations. It uses 2 inputs, the green mass proportion of the total herbage mass and the proportion of total herbage mass eaten during grazing. This can be optionally complemented with inputs of herbage chemical composition. The main outputs of the model are the proportions of green and dead herbage mass in the diet. For example, if the green proportion in the sward was 0.5 and the proportion of herbage mass eaten was 0.5, then the diet would be 0.75 green:0.25 dead; assuming 0.8 and 0.4 digestibility for green and dead material, respectively, the diet digestibility would be 0.7. PMID:20630225

Romera, A J; Gregorini, P; Beukes, P C

2010-07-01

257

Effect of gender on meat quality in lamb from extensive and intensive grazing systems when slaughtered at the end of the growing season.  

PubMed

In Norway, most lambs are slaughtered at the end of the grazing season in September. An increased demand for fresh meat during the off-season may change this pattern. Castration of male lambs is not permitted, and off-season slaughtering may affect the acceptability of the meat. The objective of this study was to determine the effect of gender and the interaction between gender and diet on meat quality from Norwegian White Sheep lambs slaughtered in September. In two different experiments, 22 and 29 males compared with 22 and 46 female lambs, respectively, were used. Loin samples of M. Longissimus dorsi were analysed for sensory profile and fatty acid composition. Meat from male lambs in Experiment 2 had higher scores for cloying and rancid flavour, and lower scores for sour and sweet taste compared to meat from female lambs. It is concluded that even at the normal slaughtering time in September, significant differences between genders may occur. PMID:21295920

Lind, Vibeke; Berg, Jan; Eilertsen, Svein Morten; Hersleth, Margrethe; Eik, Lars Olav

2011-06-01

258

The use of a geographic information system to identify a dairy goat farm as the most likely source of an urban Q-fever outbreak  

PubMed Central

Background A Q-fever outbreak occurred in an urban area in the south of the Netherlands in May 2008. The distribution and timing of cases suggested a common source. We studied the spatial relationship between the residence locations of human cases and nearby small ruminant farms, of which one dairy goat farm had experienced abortions due to Q-fever since mid April 2008. A generic geographic information system (GIS) was used to develop a method for source detection in the still evolving major epidemic of Q-fever in the Netherlands. Methods All notified Q-fever cases in the area were interviewed. Postal codes of cases and of small ruminant farms (size >40 animals) located within 5 kilometres of the cluster area were geo-referenced as point locations in a GIS-model. For each farm, attack rates and relative risks were calculated for 5 concentric zones adding 1 kilometre at a time, using the 5-10 kilometres zone as reference. These data were linked to the results of veterinary investigations. Results Persons living within 2 kilometres of an affected dairy goat farm (>400 animals) had a much higher risk for Q-fever than those living more than 5 kilometres away (Relative risk 31.1 [95% CI 16.4-59.1]). Conclusions The study supported the hypothesis that a single dairy goat farm was the source of the human outbreak. GIS-based attack rate analysis is a promising tool for source detection in outbreaks of human Q-fever.

2010-01-01

259

Design considerations for the implementation of multi-agent systems in the dairy industry  

Microsoft Academic Search

The objectives of this research were: (a) to perform a survey of current research in the area of multi-agent systems in order to learn more about how they could be designed and implemented; (b) to investigate the feasibility of such an approach for agriculture, based on an integration of currently existing technologies; and, more specifically (c) to assess the potential

Lael Parrott; René Lacroix; Kevin M Wade

2003-01-01

260

Dairy Herd Health.  

ERIC Educational Resources Information Center

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…

Wolanyk, Alison M.; Bishop, Natalie

261

The impact of 2 dipping systems on endemic stability to bovine babesiosis and anaplasmosis in cattle in 4 communally grazed areas in Limpopo Province, South Africa.  

PubMed

A 12-month study was conducted in 4 communal grazing areas in the Bushbuckridge region, Limpopo Province, South Africa. The main objective was to investigate the impact of reduced acaricide application on endemic stability to bovine babesiosis (Babesia bigemina and Babesia bovis) and anaplasmosis (Anaplasma marginale) in the local cattle population. To this end 60 cattle in each communal grazing area were bled at the beginning and the conclusion of the experimental period and their sera were assayed for B. bovis, B. bigemina and Anaplasma antibodies. Cattle in the intensively dipped group were dipped 26 times and maintained on a 14-day dipping interval throughout the study, whereas cattle in the strategically dipped group were dipped only 13 times. Three cattle, from which adult ticks were collected, were selected from each village, while immature ticks were collected by drag-sampling the surrounding vegetation. During the dipping process, a questionnaire aimed at assessing the prevalence of clinical cases of tick-borne disease, abscesses and mortalities was completed by an Animal Health Technician at each diptank. An increase in seroprevalence to B. bovis and B. bigemina and a decrease in seroprevalence to Anaplasma was detected in the strategically dipped group while in the intensively dipped group the converse was true. Amblyomma hebraeum was the most numerous tick species on the cattle, and Rhipicephalus (Boophilus) microplus was more plentiful than Rhipicephalus (Boophilus) decoloratus. Drag samples yielded more immature stages of A. hebraeum than of Rhipicephalus (Boophilus) spp. The incidence of clinical cases of tick-borne disease and of abscesses increased in the strategically dipped group at the start of the survey. PMID:16642719

Rikhotso, B O; Stoltsz, W H; Bryson, N R; Sommerville, J E M

2005-12-01

262

Preweaning Productivity of Suckling Goats and Sheep in Guadeloupe (FWI) under Intensive Reproductive Rate and Grazing Management  

Microsoft Academic Search

In Guadeloupe, small ruminants are reared for meat production under pasture conditions. Intensive rotative grazing systems (irrigated, fertilized and high-stocked tropical pastures) allow satisfactory levels of production but generate high post-grazing residues. Experiments were designed to control these. A system in which residuals were mown (RM) was tested in comparison to the control system (residuals remained, RR). The same design

E. Ortega-Jimenez; G. Alexandre; R. Arquet; M. Mahieu; A. Xandé

2005-01-01

263

Participatory modeling in dairy farm systems: a method for building consensual environmental sustainability using seasonal climate forecasts  

Microsoft Academic Search

Dairy farmers face increasing pressure to decrease environmental impact while remaining economically viable. Adaptation of\\u000a farm management practices in response to seasonal climate forecasts may be one means of achieving these objectives. This paper\\u000a describes the interactive and iterative process by which farmers, researchers, extension agents, regulatory agencies, and\\u000a other stakeholders collaborated to create, calibrate, and validate the Dynamic North

Victor E. Cabrera; Norman E. Breuer; Peter E. Hildebrand

2008-01-01

264

An integrated membrane system for the biocatalytic production of 3'-sialyllactose from dairy by-products.  

PubMed

An integrated membrane system was investigated for the production of 3'-sialyllactose by an engineered sialidase using casein glycomacropeptide (CGMP) and lactose as substrates. CGMP was purified by ultrafiltration (UF) to remove any small molecules present and then an enzymatic membrane reactor (EMR) was used to separate the product and reuse the enzyme. A PLCC regenerated cellulose membrane was found to be the most suitable for both the UF purification and EMR. Subsequently, nanofiltration (NF) was conducted to increase the purity of the 3'-sialyllactose by removing the excess lactose present. The NTR7450 membrane outperformed others in NF due to its high retention of 3'-sialyllactose (98%) and relatively low rejection of lactose (40%). The lactose in the permeate could be concentrated by the NF45 membrane and recycled into the EMR. The described integrated membrane system enables a more economic and efficient enzymatic production of 3'-sialyllactose. PMID:24880807

Luo, Jianquan; Nordvang, Rune T; Morthensen, Sofie T; Zeuner, Birgitte; Meyer, Anne S; Mikkelsen, Jørn Dalgaard; Pinelo, Manuel

2014-08-01

265

Cornell Net Carbohydrate and Protein System: A model for precision feeding of dairy cattle  

Microsoft Academic Search

The Cornell Net Carbohydrate and Protein System (CNCPS) predicts cattle requirements and nutrient supply for site-specific situations. This paper describes the CNCPS version 6 (CNCPSv6), which represents a re-engineering and updating of CNCPS version 5 with the following objectives: (1) improve the organization of the model and user interface to improve speed and accuracy in formulating diets for a herd

T. P. Tylutki; D. G. Fox; V. M. Durbal; L. O. Tedeschi; J. B. Russell; M. E. Van Amburgh; T. R. Overton; L. E. Chase; A. N. Pell

2008-01-01

266

Size and Distribution of Research Benefits in the Australian Dairy Industry  

Microsoft Academic Search

An equilibrium displacement model of the Australian dairy industry is being developed for estimating the net benefits from dairy research undertaken by DPI Victoria. In this initial version, the dairy industry is represented by a system of aggregate demand and supply relationships for two input sectors, raw milk and milk processing inputs, and three output sectors, export and domestic manufactured

Esther Liu; Katherine A. Tarrant; Christie K. M. Ho; Bill Malcolm; Garry R. Griffith

2012-01-01

267

High-temperature, air-blown gasification of dairy-farm wastes for energy production  

Microsoft Academic Search

A study was carried out to investigate the feasibility of integrating an advanced gasifier into the operation of a dairy farm for converting biomass wastes into fuel gas that can be used for power production. The disposal\\/utilization of excess animal wastes is a serious problem facing the dairy industry. Implementation of a gasification system on the dairy farm may provide

Lincoln Young; Carlson C. P. Pian

2003-01-01

268

Influence of age at first lambing on reproductive and productive performance of Lacaune dairy sheep under an intensive management system.  

PubMed

The present study investigated the effect of age at first lambing (AFL) on the performance of Lacaune sheep under intensive management conditions. Records from 3088 maiden sheep from one farm, for the period 2005-2010, were classified into four experimental groups: group E (early) ewes with AFL ?390 d; group M (middle) with AFL of 391-450 d; group L (late) with AFL of 451-510 d; and group A (aged) with AFL ?511 d. The higher the number of lactations, the lower were the yield/lactation and yield/Day in Milk. Ewes from group M up to 450 days old lambed 0.2 times more often and had 0.25 more lactations than the ewes from group L; in addition, the former group lambed 0.5 times more often and had 0.49 more lactations than ewes from group A. Group A had the lowest yield per lifetime; the yield followed the sequence: group E (1032 l) >group M (1051 l) >group L (989 l) > group A (859 l) (P<0.0001). Yield/lactation was affected by AFL during the first three lactations (P<0.05). Group E produced significantly less milk in the first lactation than ewes from groups M, L and A. AFL correlated negatively with the number of lactations in life (r= -0.26; P<0.0001) and with total milk yield (r= -209; P<0.0001). The productive performance between the ewes that reached puberty early (n=404) or late (n=2684) in life were different (P<0.0001) with the early sheep having a lower total milk yield (591 v. 1073 l, P<0.0001). In conclusion, the current study indicates that the optimal AFL for the Lacaune breed under an intensive dairy system is between 390 and 450 d. Ewes with AFL earlier than 390 d or later than 450 d are likely to have a shorter productive life and a lower lifetime milk production. PMID:21371361

Hernandez, Fernando; Elvira, Laura; Gonzalez-Martin, Juan-Vicente; Gonzalez-Bulnes, Antonio; Astiz, Susana

2011-05-01

269

Farm management factors associated with bulk tank total bacterial count in Irish dairy herds during 2006/07  

PubMed Central

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.

2009-01-01

270

Effect of different flooring systems on weight and pressure distribution on claws of dairy cows.  

PubMed

Weight and pressure distribution on the claw were studied in Swedish Holsteins housed in different flooring systems. A total of 127 cows housed in different sections of the experimental barn were used. Each section had different flooring in the walking and standing areas. There were rubber mats or abrasive mastic asphalt flooring on the alleys or a low-abrasive slatted concrete floor. Some sections had feed-stalls equipped with rubber mats; other sections did not. The vertical ground reaction force, contact area, and average contact pressure were determined on the left hind foot using the I-Scan system and analyzed with the F-scan system. These determinations were made in each of the following 3 zones of the claw: bulb, wall, and sole. Most of the weight on claws exposed to concrete floors was carried by the bulb (37.4 +/- 3.5 and 18.3 +/- 2.9% of weight exerted on the foot in the lateral and medial claw, respectively) and the wall zone (20.0 +/- 2.6 and 13.4 +/- 2.4% on lateral and medial claw, respectively). The weight and pressure distribution in cows kept on sections with rubber covered alleys but passing daily over the asphalt floor on their way to the milking parlor did not differ in any zones, except for lateral bulbs, compared with those exposed to slatted concrete alone. Still, the weight bearing of the sole zone in cows kept on rubber mats without access to asphalt was less than that of cows kept on concrete slatted floors (5.1 +/- 0.7 vs. 12.7 +/- 1.1% and 1.1 +/- 0.5 vs. 8.7 +/- 0.7% in lateral and medial claws, respectively). In cows kept on asphalt flooring without feed-stalls, most weight was exerted to the sole zone (36.2 +/- 2.9 and 22.2 +/- 1.8% in lateral and medial claws, respectively). Feed-stalls in combination with asphalt flooring yielded a decreased total contact area (30.1 +/- 1.2 cm(2)) compared with asphalt floors without feed-stalls (35.7 +/- 1.2 cm(2)). The largest total contact area was obtained on the asphalt floor without feed-stalls, resulting in a lower contact pressure (39.8 +/- 2.3 N/cm(2)) than in claws exposed to concrete (66.0 +/- 2.7 N/ cm(2)) or rubber mats (56.7 +/- 1.7 N/cm(2)). In conclusion, housing with abrasive floors resulted in claws with increased contact area at the sole surface and therefore, decreased contact pressure, but reduced the weight-bearing role of the strongest part of the claw capsule, the claw wall. PMID:18420618

Telezhenko, E; Bergsten, C; Magnusson, M; Ventorp, M; Nilsson, C

2008-05-01

271

Stochastic simulation using @Risk for dairy business investment decisions  

Microsoft Academic Search

Purpose – The purpose of this paper is to develop a dynamic, stochastic, mechanistic simulation model of a dairy business to evaluate the cost and benefit streams coinciding with technology investments. The model was constructed to embody the biological and economical complexities of a dairy farm system within a partial budgeting framework. A primary objective was to establish a flexible,

J. M. Bewley; M. D. Boehlje; A. W. Gray; H. Hogeveen; S. J. Kenyon; S. D. Eicher; M. M. Schutz

2010-01-01

272

Dairy Dilemma: Are You Getting Enough Calcium?  

MedlinePLUS

... Dairy Dilemma Dairy Dilemma Are You Getting Enough Calcium? You may be avoiding dairy products because of ... But dairy products are a major source of calcium, vitamin D and other nutrients that are important ...

273

A simulation model “CTR Dairy” to predict the supply of nutrients in dairy cows managed under discontinuous feeding patterns  

Microsoft Academic Search

A simulation rumen model has been developed to function under non-steady state conditions in order to allow prediction of nutrient availability in dairy cows managed under discontinuous feeding systems. The model simulates availability of glycogenic, aminogenic and lipogenic nutrients to lactating dairy cows fed discontinuously. The model structure considers input of up to three different feeds fed independently at any

P. Chilibroste; J. Dijkstra; P. H. Robinson; S. Tamminga

2008-01-01

274

Trend analysis of Landsat-TM and -ETM+ imagery to monitor grazing impact in a rangeland ecosystem in Northern Greece  

Microsoft Academic Search

Mediterranean rangelands are unique marginal ecosystems, which are characterized by a highly heterogeneous structure and are often interwoven with other ecosystems. Traditionally, rangelands provided resources for livestock grazing in transhumantic rotation schemes. In recent times, there has been a trend towards semi-intensive grazing systems, which is partly connected to the European system of agricultural and infrastructural subsidies, and which effectuates

A. Röder; Th. Udelhoven; J. Hill; G. del Barrio; G. Tsiourlis

2008-01-01

275

A theoretical study of the acoustic impedance of orifices in the presence of a steady grazing flow  

NASA Technical Reports Server (NTRS)

Oscillatory fluid flow in the vicinity of a circular orifice with a steady grazing flow is analyzed. A simplified system of partial differential equations is obtained by starting with the momentum and continuity equations and by assuming that the flow can be represented as an oscillatory motion superimposed on the (known) steady flow. It is found that the equations are linear in the region where grazing-flow effects dominate; a solution and the resultant orifice impedance are given for this region. It is tentatively concluded that orifice resistance is directly proportional to grazing-flow velocity and that the orifice inductive end correction is not a function of grazing flow.

Rice, E. J.

1976-01-01

276

Smallholder dairy production in Northern Malawi: production practices and constraints.  

PubMed

Milk production in Malawi is still unsatisfactory despite efforts by different stakeholders to boost the dairy sector. To investigate the roots of the problem, a survey on the current production practices and constraints on smallholder dairy farming was conducted in the Northern Region of the country. A total of 210 farmers were interviewed. The results revealed that farmers had small herd sizes in the region with an average of 2.2 ± 0.6 cattle per farmer. Average herd size was larger in male-managed farms than in female-managed farms (2.6 ± 2.8 vs. 1.8 ± 1.3), farmers with more than 5 years of dairy farming experience had larger herds than those with less experience (2.6 ± 2.8 vs. 1.9 ± 1. 2) and farmers who grazed their animals tended to have larger herds than those that stall-fed their animals (4.4 ± 5.1 vs. 1.9 ± 1.3). Average milk production was 8.2 ± 6.5 l per cow per day. Higher average daily milk production was observed in farmers with above primary school education (10.3 ± 8.3 vs. 7.7 ± 5.6), those with dairy farming as main activity (9.3 ± 6.6 vs. 6. 5 ± 6.1) and farmers with more than 2 years of experience in dairy farming (9.3 ± 6.3 vs. 6.1 ± 6.4). Unreliable supply of improved animal genetics, poor animal health, feed shortage and poor prices for milk were considered to be the most important constraints to smallholder dairy farming in descending order. PMID:21643665

Tebug, Stanly Fon; Kasulo, Victor; Chikagwa-Malunga, Susan; Wiedemann, Steffi; Roberts, David J; Chagunda, Mizeck G G

2012-01-01

277

Figure and finish of grazing incidence mirrors  

SciTech Connect

Great improvement has been made in the past several years in the quality of optical components used in synchrotron radiation (SR) beamlines. Most of this progress has been the result of vastly improved metrology techniques and instrumentation permitting rapid and accurate measurement of the surface finish and figure on grazing incidence optics. A significant theoretical effort has linked the actual performance of components used as x-ray wavelengths to their topological properties as measured by surface profiling instruments. Next-generation advanced light sources will require optical components and systems to have sub-arc second surface figure tolerances. This paper will explore the consequences of these requirements in terms of manufacturing tolerances to see if the present manufacturing state-of-the-art is capable of producing the required surfaces. 15 refs., 14 figs., 2 tabs.

Takacs, P.Z. (Brookhaven National Lab., Upton, NY (USA)); Church, E.L. (Picatinny Arsenal, Dover, NJ (USA). Army Armament Research, Development and Engineering Center)

1989-08-01

278

Acoustic grazing flow impedance using waveguide principles  

NASA Technical Reports Server (NTRS)

A grazing flow apparatus was designed to measure the impedance of acoustic materials when installed in environments that subject the material to grazing airflow. The design of the apparatus and the data analysis technique is based on the solution of the convected wave equation in an infinite length waveguide.

Armstrong, D. L.

1971-01-01

279

Sustainable Rangeland Grazing in Norse Faroe  

Microsoft Academic Search

The introduction of domestic livestock, particularly sheep, and rangeland grazing by Norse settlers to Faroe during the ninth century has generally been described as a major pressure on a sensitive landscape, leading to rapid and widespread vegetation change and contributing to land degradation. This view has, however, been developed without consideration of Norse grazing management practices which may have served

Amanda M. Thomson; Ian A. Simpson; Jennifer L. Brown

2005-01-01

280

Effects of Warming and Grazing on Ecosystem Respiration in the Alpine Meadow on the Tibetan Plateau  

NASA Astrophysics Data System (ADS)

Intensive studies reveal that there is much uncertainty regarding how ecosystem and soil respiration will respond to warming and grazing, especially in the alpine meadow ecosystem. We conducted a first of its kind field-manipulative warming and grazing experiment in an alpine meadow on the Tibetan plateau to determine the effects of warming and grazing on ecosystem and soil respiration for 3-years, from 2006 to 2008 at the Haibei Alpine Meadow Ecosystem Research Station. The infrared heaters were controlled using the proportional-integral-derivative-outputs (PID) control system so as to ensure constant warming between heated and reference plots. The setpoint differences of the vegetation canopy between heated and corresponding reference plots were 1.2oC during daytime and 1.7oC at night during the growing season (from May to September). A two factorial design (warming and grazing) was used with four replicates of each of four treatments: no-warming with no-grazing (NWNG), no-warming with grazing (NWG), warming with no-grazing (WNG), and warming with grazing (WG). Generally, warming and grazing did not affect seasonal average ecosystem respiration (Re), and there was no interaction between grazing and warming. However, they significantly affected the Re early in the growing season and by the end of the growing season. Warming significantly increased seasonal average soil respiration (Rs) by 9.2%, whereas the difference mainly resulted from data gathered early in the growing season, before June 2007. Positive correlations between soil temperature and Re and Rs were observed, and soil temperature explained 63-83% of seasonal Re variations during the 3-year study and 19-34% of Rs variations in 2007. Seasonal Re in 2008 and Rs in 2007 were slightly negatively correlated to soil moisture, but interannual average Re decreased with a decrease in precipitation for all treatments. Warming and grazing reduced the Q10 value of Re in 2007 and 2008 but did not affect the Q10 value of Rs. The Q10 values of Rs were much lower than the Q10 values of Re in 2007. These results suggest that grazing may reduce the temperature sensitivity of Re and that Re was main controlled by soil temperature rather than moisture which varied with timescale in the alpine meadow. Keywords: warming; grazing; ecosystem respiration; soil respiration; alpine meadow; soil temperature and moisture; climate change; Tibetan plateau

Wang, S.; Lin, X.

2011-12-01

281

76 FR 31977 - Notice of Intent To Prepare an Environmental Impact Statement for Domestic Sheep Grazing...  

Federal Register 2010, 2011, 2012, 2013

...Environmental Impact Statement for Domestic Sheep Grazing Allotments for Term Grazing Permit...related to the potential renewal of domestic sheep grazing permits on 12 allotments and 1...SUPPLEMENTARY INFORMATION: Term permits on 12 sheep grazing and 1 cattle grazing...

2011-06-02

282

Mycobacterium tuberculosis infection in grazing cattle in central Ethiopia.  

PubMed

A preliminary study to characterise mycobacteria infecting tuberculous cattle from two different management systems in central Ethiopia was carried out. Approximately 27% of isolates from grazing cattle were Mycobacterium tuberculosis, while cattle in a more intensive-production system were exclusively infected with M. bovis. The practice of local farmers discharging chewed tobacco directly into the mouths of pastured cattle was identified as a potential route of human-to-cattle transmission of M. tuberculosis. PMID:20965132

Ameni, Gobena; Vordermeier, Martin; Firdessa, Rebuma; Aseffa, Abraham; Hewinson, Glyn; Gordon, Stephen V; Berg, Stefan

2011-06-01

283

Grazed riparian management and stream channel response in southeastern Minnesota (USA) streams.  

PubMed

The U.S. Department of Agriculture-Natural Resources Conservation Service has recommended domestic cattle grazing exclusion from riparian corridors for decades. This recommendation was based on a belief that domestic cattle grazing would typically destroy stream bank vegetation and in-channel habitat. Continuous grazing (CG) has caused adverse environmental damage, but along cohesive-sediment stream banks of disturbed catchments in southeastern Minnesota, short-duration grazing (SDG), a rotational grazing system, may offer a better riparian management practice than CG. Over 30 physical and biological metrics were gathered at 26 sites to evaluate differences between SDG, CG, and nongrazed sites (NG). Ordinations produced with nonmetric multidimensional scaling (NMS) indicated a gradient with a benthic macroinvertebrate index of biotic integrity (IBI) and riparian site management; low IBI scores associated with CG sites and higher IBI scores associated with NG sites. Nongrazed sites were associated with reduced soil compaction and higher bank stability, as measured by the Pfankuch stability index; whereas CG sites were associated with increased soil compaction and lower bank stability, SDG sites were intermediate. Bedrock geology influenced NMS results: sites with carbonate derived cobble were associated with more stable channels and higher IBI scores. Though current riparian grazing practices in southeastern Minnesota present pollution problems, short duration grazing could reduce sediment pollution if managed in an environmentally sustainable fashion that considers stream channel response. PMID:18481141

Magner, Joseph A; Vondracek, Bruce; Brooks, Kenneth N

2008-09-01

284

Spatial and Temporal Alterations on Carbon and Water Cycles Due to Grazing  

NASA Astrophysics Data System (ADS)

Grasslands are vital in the carbon cycle, as large amounts of carbon are stored in the soils of the prairie. As climate change affects the carbon cycle, it is essential for the agricultural communities to understand the impacts of these changes on farming practices such as grazing and meat production. The objective of this study is to determine the effect of grazing on the carbon cycle by characterizing the surface boundary layer of both a grazed field and an ungrazed field. Data were collected from open path eddy covariance systems over Rannells Flint Hills Prairie Preserve in north-central Kansas, one over an ungrazed field and one over a grazed field. Cospectra of fluxes of CO2, heat, water, and momentum for July 2007 were compared to assess the size of eddies contributing energy to each field. For CO2, the cospectra for both the ungrazed and the ungrazed field were similar. For all of the other fluxes, lower frequency eddies contributed more energy in the grazed field than the ungrazed field. By using a footprint model, the contributing source areas were determined for fluxes from May through October of 2007. The grazed field had a larger distance of contribution in both stable and unstable atmospheric conditions. Implications of this study include the alterations on fields and impacts on the carbon and water cycles as a result of grazing.

Maksimowicz, M. M.; Brunsell, N. A.; Ham, J. M.

2009-05-01

285

Dairy cows' reproductive response to feeding level differs according to the reproductive stage and the breed.  

PubMed

Reproductive performance has decreased over the last decades in many dairy systems. This study aimed at comparing the effects of a high- and a low-feeding level on reproductive stages (cyclicity, oestrus and fertility) of Holstein and Normande cows in a grass-based winter compact calving system. High-fed cows received a total mixed ration composed of 55% maize silage, 15% dehydrated alfalfa pellets and 30% concentrate in winter and 4 kg/day concentrate supply at grazing. Low-fed cows only received 50% grass silage and 50% haylage in winter and no concentrate at grazing. Low-fed cows produced less milk over 44 weeks, but lost more body condition (BC) than high-fed ones (5207 v. 7457 kg, -1.28 v. -0.96 unit, P < 0.001). Normande cows produced less milk and lost less BC than Holstein ones (5596 v. 7068 kg, -0.89 v. -1.36 unit, P < 0.001). Post-partum ovarian activity was little affected by the feeding level. In both breeds, ovulation detection rate was higher in low-fed cows (74% v. 59%, P < 0.001) and detection relied more frequently on standing behaviour (67% v. 55%, P = 0.022). In both breeds, the recalving rate following the first and second inseminations was not significantly affected by the feeding level, although more non-fertilisations or early embryo mortalities occurred in low-fed cows (43% v. 26%, P = 0.004). For the Holstein breed, this was clearly explained by more late embryo mortalities in high-fed cows (30% v. 9%, P = 0.004). Finally, pregnancy rate by the end of the 13-week breeding period was similar between feeding groups. Conversely, the Normande dual-purpose cows had a higher pregnancy rate by the end of the breeding period than the Holstein dairy cows (72% v. 54%, P = 0.007), owing to a better ovarian activity (79% v. 54% normal, P < 0.001) and a higher recalving rate following insemination (53% v. 37%, P = 0.007). In conclusion, this study demonstrates that feeding levels with converse effects on milk yield and BC score also have converse effects on reproductive stages and lead to quite similar final reproductive performance in compact calving systems. Normande cows benefit from an overall better reproductive performance, but do not suit high feeding levels for very compact calving systems owing to depressed oestrous behaviour. PMID:22439995

Cutullic, E; Delaby, L; Gallard, Y; Disenhaus, C

2011-04-01

286

Biodegradability evaluation of dairy effluents originated in selected sections of dairy production.  

PubMed

Main goal of the study was present the results of some respirometric measurements of activated sludge biodegrading the substrate in the wastewater originated in selected sections of the dairy processing line. The following dairy production effluents were analyzed in the research: the pumping station wastewater (combined wastewater from all the sections of the dairy factory), the apparatus room wastewater, the butter section wastewater, the milk reception point wastewater, the cheese section wastewater and the cottage cheese section wastewater. Apart from that, sweet and sour whey, which are secondary products of hard cheese and cottage cheese production, respectively, was the subject of the research. The amount of organic matter being oxidized during a 5-day measurement session was calculated on 1g of the activated sludge biomass. The research was conducted at the temperature of 20 degrees C and 35 degrees C at the applied sludge loading rate of A'=0.2 g BOD g(-1) dry mass d(-1), which ensured complete biodegradation. The results indicated a correlation between a technological process of dairy processing, an ultimate outcome of which was the wastewater analyzed, and dairy wastewater biodegradability. The results confirmed that all dairy processing effluents can be treated together, with the exception of whey, whose complex biodegradation demands may cause too much burden to any wastewater treatment technological system and thus should be managed within a separate installation. PMID:17976980

Janczukowicz, W; Zieli?ski, M; Debowski, M

2008-07-01

287

Soil organic carbon responses to grazing and woody plant encroachment in a semi-desert grassland  

NASA Astrophysics Data System (ADS)

The majority of carbon (C) in grassland and savanna ecosystems is belowground. Recent estimates suggest the historic and ongoing proliferation of woody plants in these systems may account for a significant fraction of the Northern Hemisphere carbon (C) sink. A large degree of uncertainty in the direction and magnitude of soil C pool response to woody encroachment exists, however. Soil organic C (SOC) response to woody encroachment may be modified by current and historical land management patterns, but the nature of these relationships is poorly understood. We used CENTURY, a process-based ecosystem model, to explore historical patterns and project future changes in SOC in response to Prosopis velutina encroachment and livestock grazing in a southern Arizona semi-desert grassland. We parameterized and adapted CENTURY for our study site using woody and herbaceous biomass data and P. velutina growth rate estimates. Modeled contemporary SOC levels were +/- 15% of measured levels. Simulations of historical grazing management suggest that grassland SOC dropped nearly 50% (from 1020 to 530 g C m-2) in response to heavy, continuous livestock grazing initiated around 1850. SOC recovery varied with the degree of relaxation of grazing intensity, with nearly full recovery occurring in areas where grazing was excluded between 1903 and 2005 (modeled SOC = 930 g C m-2 in 2005). Woody encroachment, beginning around 1900, had a strong positive influence on modeled SOC, with the greatest accumulations associated with plants greater than 60 years old. Grazing mediated this response, such that sub-canopy SOC in grazed areas was 200-300 g C m-2 less than that in ungrazed areas. Forward simulations suggest that SOC will continue to increase until woody plant stands reach ca. 130 years of age, at which point SOC will stabilize around 3300 g C m^{- 2} for grazed sites and 3000 g C m-2 for ungrazed sites. Results indicate that woody plant encroachment has strong positive influence on SOC accumulation that is partially offset by grazing.

Throop, H. L.; Archer, S. R.; McClaran, M.; Ojima, D.; Keough, C.; Parton, W.

2006-12-01

288

How do sheep exploit pastures? An overview of their grazing behaviour from homogeneous swards to complex grasslands  

Microsoft Academic Search

SUMMARY - A better knowledge of the interactions between plants and herbivores is needed to define appropriate management strategies for animals and grasslands within the context of sustainable grazing systems. Small ruminants exploit a wide range of resources from homogeneous swards and grass-clover associations to highly biodiverse grasslands and shrubby rangelands. In this paper, we first analyse how sheep graze

B. Dumont; S. Prache; P. Carrère; A. Boissy

289

Grazing incidence optics; Proceedings of the Meeting, Orlando, FL, Apr. 3, 4, 1986  

NASA Technical Reports Server (NTRS)

Papers are presented on the diffraction-limited performance of grazing incidence optical systems; transverse ray aberrations of Wolter type 1 telescopes; hybrid X-ray telescope systems; surface characterization of grazing incidence optics in the extreme UV and X-ray regions; and the surface roughness properties of synchrotron radiation optics. Topics discussed include the simulation of free-abrasive grinding of grazing incidence mirrors with vertical-honing and flexible blades; mirrors for the Extreme Ultraviolet Explorer; the design and development of conical X-ray imaging mirrors; thermal loading considerations for synchrotron radiation mirrors; and grazing incidence optics for synchrotron radiation insertion-device beams. Consideration is given to the interpretation of glancing incidence scattering measurements; damage processes in short wavelength coated FEL optics; the replication of grain incidence optics; and the assembly and alignment of the Technology Mirror Assembly.

Osantowski, John F. (editor); Van Speybroeck, Leon (editor)

1986-01-01

290

Local feeding strategies and milk composition in small-scale dairy production systems during the rainy season in the highlands of Mexico.  

PubMed

The objective of the work was to identify local feeding strategies in small-scale dairy production systems during the rainy season in the highlands of Mexico, and to determine their effects on milk yields (MY), milk composition and economic viability. Twenty-two dairy farms were monitored by monthly visits, recording and sampling milk from between two and six cows in each farm, live-weight was also recorded. Samples from feeds used in that month were taken and feeds given to the dairy herd were weighed. Economic data was also recorded. Milk composition and milk urea nitrogen were determined, as well as chemical composition of feeds. Eighteen feedstuffs were identified, grouped in: HNH feeds-high in neutral detergent fibre (NDF) and in DM matter; HNL feeds-high in NDF but low in DM; HCh feeds-high in non-fibrous carbohydrates; and HCP feeds-high in crude protein. Four feeding strategies were identified: strategy 1 uses HND, HNL and HCP; strategy 2-HND, HNL, HCh and HCP; strategy 3 HNH and HCP; and strategy 4 HNL and HCP. Of participating farms, 73.4% followed strategy 1, 11.3% strategy 2, 11.3% strategy 4 and 3.8% strategy 3. There were no statistical differences (P?>?0.05) between strategies for MY and milk composition, but there were differences (P??0.05) model relating intake of feed groups and milk fat content, but milk protein and SNF contents were significantly explained by intake of HCP. When expressed as MY and milk components yield, milk fat yield was significantly explained by intake of all four feed groups, but milk protein and SNF yields were explained only by intake of HCP and LW. MUN excretion was explained also by HCP intake. All feeding strategies produced positive economic returns, on average generating the equivalent of 3.45 minimum wages of the area. PMID:21822985

Alfonso-Ávila, Ángel René; Wattiaux, Michel A; Espinoza-Ortega, Angélica; Sánchez-Vera, Ernesto; Arriaga-Jordán, Carlos M

2012-03-01

291

Recommended Amounts of Total dairy  

Cancer.gov

Recommended Amounts of Total dairy Table B15. Total dairy: Estimated percentage of persons below, at, or above recommendation1 Age (years) N Mean (SE) % with intake below recommendation (SE) % with intake meeting recommendation (SE) % with intake above

292

Winter feeding systems and dairy cow breed have an impact on milk composition and flavour of two Protected Designation of Origin French cheeses.  

PubMed

This study investigates the effects of two feeding systems and two dairy cow breeds on milk yield and composition, physical and sensorial properties of Camembert and Pont-l'Evêque cheeses. The experiment consisted of a 2 × 2 factorial arrangement of treatments. A low energy grass diet with only 15% of concentrate (LowGS) was compared with a high-energy maize silage diet with 30% concentrate (HighMS). Thirty-four Holstein (Ho) and 34 Normande (No) cows in early lactation were assigned to one of two feeding systems for a 6-week period. Cows on the LowGS feeding system had lower milk yield, fat and protein content. In both feeding systems, No cows had lower milk yields but higher milk protein contents than Ho cows. The LowGS feeding system altered milk fatty acid (FA) composition by reducing saturated FA. Breed had only a small impact on milk FA. Concerning milk coagulating properties, only the firmness was reduced by the LowGS feeding and the Ho breed. The effects of breed and feeding system on the protein content of cheeses were more marked in Camembert cheese than in Pont-l'Evêque cheese. However, the Camembert cheese from Ho-LowGS was, in fact, characterized especially by lower protein content. LowGS feeding system and No breed produced more yellow cheeses. Feeding systems had limited effects on the firmness of Camembert and Pont-l'Evêque cheeses measured by penetrometry. In sensory analysis, Ho breed and LowGS feeding produced a Camembert cheese with a more melting texture in the mouth due to the increase of spreadability index and of proteolysis. The type of cheese also had an influence: the effects were more important on Camembert cheese than on Pont-l'Evêque cheese. Only the Ho-LowGS treatment produced a very specific Camembert cheese different from the others. The feeding systems and breed of dairy cow have no determinant effect on PDO (protected designation of origin) Camembert and Pont-l'Evêque cheeses, especially regarding taste. In this kind of trial, despite the effects of feeding systems and breed on milk composition, the role of cheese ripening and microbiology appears to be of considerable importance. PMID:22444910

Hurtaud, C; Peyraud, J L; Michel, G; Berthelot, D; Delaby, L

2009-09-01

293

25 CFR 167.11 - Tenure of grazing permits.  

Code of Federal Regulations, 2011 CFR

...BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER NAVAJO GRAZING REGULATIONS § 167.11 Tenure of grazing...or portions of grazing permits are beneficial in aiding range recovery. Each District Grazing Committee will handle each matter...

2011-04-01

294

The effect of grazing on the spatial heterogeneity of vegetation  

Microsoft Academic Search

Grazing can alter the spatial heterogeneity of vegetation, influencing ecosystem processes and biodiversity. Our objective was to identify why grazing causes increases in the spatial heterogeneity of vegetation in some cases, but decreases in others. The immediate effect of grazing on heterogeneity depends on the interaction between the spatial pattern of grazing and the pre-existing spatial pattern of vegetation. Depending

P. B. Adler; D. A. Raff; W. K. Lauenroth

2001-01-01

295

Annual replacement of the tillers of Agropyron desertorum following grazing  

Microsoft Academic Search

The annual replacement of tillers of Agropyron desertorum (Fisch. ex Link) Schult., a grazing-tolerant, Eurasian tussock grass, was examined in the field following cattle grazing. Heavy grazing before internode (culm) elongation seldom affected tiller replacement. Heavy grazing during or after internode elongation, which elevates apical meristems, increased overwinter mortality of fall-produced tillers and reduced the number and heights of these

B. E. Olson; J. H. Richards

1988-01-01

296

Multi-paddock grazing on rangelands: why the perceptual dichotomy between research results and rancher experience?  

PubMed

Maintaining or enhancing the productive capacity and resilience of rangeland ecosystems is critical for the continued support of people who depend on them for their livelihoods, especially in the face of climatic change. This is also necessary for the continued delivery of ecosystem services derived from rangelands for the broader benefit of societies around the world. Multi-paddock grazing management has been recommended since the mid-20th century as an important tool to adaptively manage rangelands ecosystems to sustain productivity and improve animal management. Moreover, there is much anecdotal evidence from producers that, if applied appropriately, multi-paddock grazing can improve forage and livestock production. By contrast, recent reviews of published rangeland-based grazing systems studies have concluded that, in general, field trials show no superiority of vegetation or animal production in multi-paddock grazing relative to continuous yearlong stocking of single-paddock livestock production systems. Our goal is to provide a framework for rangeland management decisions that support the productivity and resiliency of rangelands and then to identify why different perceptions exist among rangeland managers who have effectively used multi-paddock grazing systems and research scientists who have studied them. First, we discuss the ecology of grazed ecosystems under free-ranging herbivores and under single-paddock fenced conditions. Second, we identify five principles underpinning the adaptive management actions used by successful grazing managers and the ecological, physiological, and behavioral framework they use to achieve desired conservation, production, and financial goals. Third, we examine adaptive management principles needed to successfully manage rangelands subjected to varying environmental conditions. Fourth, we describe the differences between the interpretation of results of grazing systems research reported in the scientific literature and the results reported by successful grazing managers; we highlight the shortcomings of most of the previously conducted grazing systems research for providing information relevant for rangeland managers who aim to achieve desired environmental and economic goals. Finally, we outline knowledge gaps and present testable hypotheses to broaden our understanding of how planned multi-paddock grazing management can be used at the ranching enterprise scale to facilitate the adaptive management of rangelands under dynamic environmental conditions. PMID:23850765

Teague, Richard; Provenza, Fred; Kreuter, Urs; Steffens, Tim; Barnes, Matt

2013-10-15

297

Untangling the roles of fire, grazing and rainfall on small mammal communities in grassland ecosystems  

Microsoft Academic Search

In grassland systems across the globe, ecologists have been attempting to understand the complex role of fire, grazing and\\u000a rainfall in creating habitat heterogeneity and the consequences of anthropogenic control of these factors on ecosystem integrity\\u000a and functioning. Using a South African grassland ecosystem as a model, we investigated the impact of fire and grazing pressure\\u000a on small mammal communities

R. W. Yarnell; D. M. Scott; C. T. Chimimba; D. J. Metcalfe

2007-01-01

298

Influences of grazing and exclosure on carbon sequestration in degraded sandy grassland, Inner Mongolia, north China  

Microsoft Academic Search

Livestock grazing is recognised as one of the main causes of vegetation and soil degradation\\/desertification in the semi?arid Horqin sandy steppe of northern China. In this paper, soil?plant system carbon (C) in a representative degraded sandy grassland in the Horqin sandy steppe (42°58’ N, 120°42'E altitude c. 360 m a.s.l.) was measured. Three situations: long?term continuous grazing (CG), exclosure for

Yong Zhong Su; Ha Lin Zhao; Tong Hui Zhang

2003-01-01

299

Herds of methane chambers grazing bubbles  

NASA Astrophysics Data System (ADS)

Water to air methane emissions from freshwater reservoirs can be dominated by sediment bubbling (ebullitive) events. Previous work to quantify methane bubbling from a number of Australian sub-tropical reservoirs has shown that this can contribute as much as 95% of total emissions. These bubbling events are controlled by a variety of different factors including water depth, surface and internal waves, wind seiching, atmospheric pressure changes and water levels changes. Key to quantifying the magnitude of this emission pathway is estimating both the bubbling rate as well as the areal extent of bubbling. Both bubbling rate and areal extent are seldom constant and require persistent monitoring over extended time periods before true estimates can be generated. In this paper we present a novel system for persistent monitoring of both bubbling rate and areal extent using multiple robotic surface chambers and adaptive sampling (grazing) algorithms to automate the quantification process. Individual chambers are self-propelled and guided and communicate between each other without the need for supervised control. They can maintain station at a sampling site for a desired incubation period and continuously monitor, record and report fluxes during the incubation. To exploit the methane sensor detection capabilities, the chamber can be automatically lowered to decrease the head-space and increase concentration. The grazing algorithms assign a hierarchical order to chambers within a preselected zone. Chambers then converge on the individual recording the highest 15 minute bubbling rate. Individuals maintain a specified distance apart from each other during each sampling period before all individuals are then required to move to different locations based on a sampling algorithm (systematic or adaptive) exploiting prior measurements. This system has been field tested on a large-scale subtropical reservoir, Little Nerang Dam, and over monthly timescales. Using this technique, localised bubbling zones on the water storage were found to produce over 50,000 mg m-2 d-1 and the areal extent ranged from 1.8 to 7% of the total reservoir area. The drivers behind these changes as well as lessons learnt from the system implementation are presented. This system exploits relatively cheap materials, sensing and computing and can be applied to a wide variety of aquatic and terrestrial systems.

Grinham, Alistair; Dunbabin, Matthew

2014-05-01

300

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

PubMed

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. PMID:17451622

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

2007-08-01

301

Effects of the different rates of urease and nitrification inhibitors on gaseous emissions of ammonia and nitrous oxide, nitrate leaching and pasture production from urine patches in an intensive grazed pasture system  

Microsoft Academic Search

Minimizing nitrogen (N) losses via ammonia (NH3) and nitrous oxide (N2O) emissions into the atmosphere and nitrate (NO3?) leaching into surface and ground waters from intensively grazed pastures is essential for environmental protection worldwide. Applying urease inhibitor such as N-(n-butyl) thiophosphoric triamide (nBPT) or (Agrotain) and nitrification inhibitor dicyandiamide (DCD) to grazed pastures has the potential to mitigate such N

M. Zaman; J. D. Blennerhassett

2010-01-01

302

Antimicrobial activity of nisin, reuterin, and the lactoperoxidase system on Listeria monocytogenes and Staphylococcus aureus in cuajada, a semisolid dairy product manufactured in Spain.  

PubMed

The inhibitory activity of nisin (N), reuterin (R), and the lactoperoxidase system (LPS), added individually or in combination, against Listeria monocytogenes and Staphylococcus aureus was investigated in "cuajada" (curdled milk), a semisolid dairy product manufactured in Spain. Cuajada was manufactured from UHT skim milk separately inoculated with L. monocytogenes and Staph. aureus, each at approximately 4 log cfu/mL, and held under conditions of temperature abuse (10 degrees C). On d 3, a synergistic bactericidal activity was observed for the combinations of biopreservatives assayed, with L. monocytogenes counts of only 0.30 log cfu/mL in cuajada made with N + R + LPS vs. 8.31 log cfu/mL in control cuajada. After 12 d, L. monocytogenes could not be detected in cuajada made with added N + LPS or N + R + LPS. Staphylococcus aureus was more resistant than L. monocytogenes to biopreservatives added individually. On d 3, the synergistic effect of the 3 biopreservatives against Staph. aureus resulted in counts of 3.03 log cfu/mL in cuajada made with N + R + LPS vs. 6.40 in control cuajada. After 12 d, Staph. aureus counts were 2.61 log cfu/mL in cuajada made with N + R + LPS, whereas they ranged from 6.11 to 7.70 log cfu/mL in control cuajada and in cuajada made with other combinations of biopreservatives. The most pronounced decrease in pathogen counts was achieved by the triple combination N + R + LPS, which acted synergistically on the inactivation of L. monocytogenes and Staph. aureus in cuajada over 12 d at 10 degrees C. The treatment combining these 3 natural biopreservatives at low concentrations, within the hurdle concept of food preservation, might be a useful tool to control the growth of pathogenic microorganisms in nonacidified dairy products. PMID:18096926

Arqués, J L; Rodríguez, E; Nuñez, M; Medina, M

2008-01-01

303

Assessment of an accelerometer system for detection of estrus and treatment with gonadotropin-releasing hormone at the time of insemination in lactating dairy cows.  

PubMed

Two experiments were conducted to evaluate an accelerometer system (Heatime; SCR Engineers Ltd., Netanya, Israel) to manage reproduction in lactating dairy cows. In experiment 1, lactating Holstein cows (n=112) were fitted with an accelerometer system and were treated with GnRH followed 7d later by PGF(2?) to synchronize estrus. A total of 89 cows that had a follicle >10mm in diameter and a functional corpus luteum at the PGF(2?) injection that regressed by 48 h after induction of luteolysis were included in the analysis. Overall, 71% of cows were detected in estrus by the accelerometer system and 95% of cows showing estrus ovulated within 7d after induction of luteolysis. Of the cows not detected in estrus by the accelerometer system, 35% ovulated within 7d after induction of luteolysis. Duration of estrus activity (mean ± SD) was 16.1±4.7 h and was neither affected by parity nor milk production. Intervals (means ± SD) from induction of luteolysis, onset of activity, peak raw activity, and peak weighted activity to ovulation was 82.2±9.5, 28.7±8.1, 20.4±7.8, and 16.4±7.4 h, respectively, and the interval from AI to ovulation was 7.9±8.7 h, but ranged from -12 to 26 h. In experiment 2, cows were assigned randomly to receive an intramuscular injection of GnRH at artificial insemination (AI) after detection of estrus by the accelerometer system or receive no treatment (control). Nine hundred seventy-nine AI services from 461 cows were analyzed. Treatment with GnRH at AI did not affect fertility at 35 or 65 d after AI, and no interaction was detected between treatment and season or treatment and AI number. Overall, two-thirds of the cows that were considered properly synchronized were inseminated based on the accelerometer system and ovulated after AI. The remaining cows either were not inseminated because they were not detected in estrus or would not have had a chance to conceive to AI because they failed to ovulate after estrus. Furthermore, mean time of AI in relation to ovulation determined by the accelerometer system was acceptable for most of the cows that displayed estrus; however, variability in the duration of estrus and timing of AI in relation to ovulation could lead to poor fertility in some cows. For lactating dairy cows detected in estrus by the accelerometer system, treatment with GnRH at the time of AI without reference to the onset of estrus did not increase fertility. PMID:23040033

Valenza, A; Giordano, J O; Lopes, G; Vincenti, L; Amundson, M C; Fricke, P M

2012-12-01

304

A longitudinal study on morbidity and mortality in youngstock smallholder dairy cattle with special reference to tick borne infections in Tanga region, Tanzania.  

PubMed

The incidence and potential determinants of tick borne diseases (TBDs) were estimated in a longitudinal study that was conducted in cohorts of youngstock animals of less than 3 years kept in smallholder dairy farms in Tanga region, Tanzania. A combination of serological tests, blood and lymph node smears were used as diagnostic tests for TBDs during the study. A total number of 549 youngstock were followed for a total of 532.2 animal years from August 1999 to July 2001. Overall morbidity and mortality rates (due to all causes) were 8.26 and 12.0 per 100 animals year at risk, respectively. Of the total deaths, 56% were attributed to TBDs (37.5%-East Coast fever (ECF) and 18%-anaplasmosis). Specific morbidity and mortality rates for ECF were estimated to be 3.57 and 4.51 per 100 animals year risk, respectively, and for anaplasmosis 2.21 and 2.25 per 100 animals year risk, respectively. Analysis of survival times to death indicated that calves < 6 months of age and those out on pasture had higher death rates than older calves and those kept under zero-grazing systems (relative risk [RR] 3.80, P = 0.001 for pasture-grazed calves). There was no mortality or morbidity arising specifically from cowdriosis (heartwater) or babesiosis during the whole period of monitoring. The study revealed that most farms were applying under strength acaricide and using acaricides at irregular intervals. It is concluded that TBDs namely ECF and anaplasmosis are important diseases in this farming system and reducing morbidity and mortality in smallholder dairy farms in Tanga region is an achievable goal. Both farmers and extension services should target at risk calves with the provision of both strict tick control and optimal husbandry management practices. PMID:19091478

Swai, Emmanuel S; Karimuribo, Esron D; Kambarage, Dominic M; Moshy, Winford E

2009-03-01

305

36 CFR 292.48 - Grazing activities.  

Code of Federal Regulations, 2013 CFR

...Lands in the HCNRA. (a) Grazing may be authorized only on rangeland determined by the authorized officer to be suitable for...and scientific values; rare combinations of outstanding ecosystems, or the protection and enhancement of the values for...

2013-07-01

306

25 CFR 167.8 - Grazing rights.  

Code of Federal Regulations, 2011 CFR

...who have acquired grazing rights by marriage, inheritance, purchase or division of permits. Whenever the permitted number of sheep units within a district is less than the carrying capacity, new permits to the carrying capacity limit may be granted as...

2011-04-01

307

Grazing of a Tetrahymena sp. on Adhered Bacteria in Percolated Columns Monitored by In Situ Hybridization with Fluorescent Oligonucleotide Probes  

PubMed Central

Predation of attached Pseudomonas putida mt2 by the small ciliate Tetrahymena sp. was investigated with a percolated column system. Grazing rates were examined under static and dynamic conditions and were compared to grazing rates in batch systems containing suspended prey. The prey densities were 2 × 108 bacteria per ml of pore space and 2 × 108 bacteria per ml of suspension, respectively. Postingestion in situ hybridization of bacteria with fluorescent oligonucleotide probes was used to quantify ingestion. During 30 min, a grazing rate of 1,382 ± 1,029 bacteria individual?1 h?1 was obtained with suspended prey; this was twice the grazing rate observed with attached bacteria under static conditions. Continuous percolation at a flow rate of 73 cm h?1 further decreased the grazing rate to about 25% of the grazing rate observed with suspended prey. A considerable proportion of the protozoans fed on neither suspended bacteria nor attached bacteria. The transport of ciliates through the columns was monitored at the same time that predation was monitored. Less than 20% of the protozoans passed through the columns without being retained. Most of these organisms ingested no bacteria, whereas the retained protozoans grazed more efficiently. Retardation of ciliate transport was greater in columns containing attached bacteria than in bacterium-free columns. We propose that the correlation between grazing activity and retardation of transport is a consequence of the interaction between active predators and attached bacteria.

Eisenmann, Heinrich; Harms, Hauke; Meckenstock, Rainer; Meyer, Elisabeth I.; Zehnder, Alexander J. B.

1998-01-01

308

Metabolic profile in Chilota lambs grazing Calafatal.  

PubMed

The aim of this study was to determine the productive and metabolic response in Chilota lambs grazing Calafatal or naturalized pasture. The experiment was conducted at the Experimental Station Butalcura (INIA, Chiloé) during October, November, and December 2011. Eight Chilota and six Suffolk Down 2-month-old lambs, uncastrated males, no twin, were located to graze a typical secondary succession of the Chiloé Archipelago, as a Calafatal (a secondary succession which derivates from human intervention on native forest in Chiloé Archipelago). Simultaneously, eight male 2-month-old Chilota lambs were located to graze a naturalized pasture, another secondary succession derived from human intervention on native forest in Chiloé Archipelago. Animals had free access to water sources. Measurements were performed one time a month, for three consecutive months for productive indicators: live weight, average daily gain and body condition score, and blood indicators of protein and energetic metabolism. Productive and metabolic response was similar between both types of pastures (P > 0.05). However, Chilota and Suffolk Down lambs grazing Calafatal showed higher plasma concentrations of ?OH-butyrate, but lower non-esterified fatty acids (NEFA) than Chilota lambs grazing naturalized pasture (P < 0.05). Chilota lambs grazing naturalized pasture showed the highest plasma concentrations of NEFA and urea (P < 0.05). It was concluded that, under the conditions of the study, Chilota lambs grazing naturalized pasture, which had higher contents of crude protein and metabolizable energy, showed better metabolic balance, but not performance, than Chilota and Suffolk Down lambs grazing Calafatal. PMID:24420763

Gallardo, María Asunción; Noro, Mirela; De la Barra, Rodrigo; Pulido, Rubén

2014-04-01

309

Grazing resistance in nutrient-stressed phytoplankton  

Microsoft Academic Search

Grazing experiments were performed with the zooplankters Daphnia pulex and Daphnia magna, feeding on phosphorus-saturated and phosphorus-limited cells of two green algae (Scenedesmus subspicatus and Selenastrum capricornutum). P-limited algal cells passed largely intact through the gut and were thus spared from heavy grazing pressure. P-saturated algal cells, in contrast, were efficiently assimilated. Structural and morphological changes in the P-limited cells

Ellen Donk; Dag O. Hessen

1993-01-01

310

Linear Classification of Dairy Cattle. Slide Script.  

ERIC Educational Resources Information Center

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

Sipiorski, James; Spike, Peter

311

Grazing-activated chemical defence in a unicellular marine alga  

NASA Astrophysics Data System (ADS)

Marine plankton use a variety of defences against predators, some of which affect trophic structure and biogeochemistry. We have previously shown that, during grazing by the protozoan Oxyrrhis marina on the alga Emiliania huxleyi, dimethylsulphoniopropionate (DMSP) from the prey is converted to dimethyl sulphide (DMS) when lysis of ingested prey cells initiates mixing of algal DMSP and the enzyme DMSP lyase. Such a mechanism is similar to macrophyte defence reactions,. Here we show that this reaction deters protozoan herbivores, presumably through the production of highly concentrated acrylate, which has antimicrobial activity. Protozoan predators differ in their ability to ingest and survive on prey with high-activity DMSP lyase, but all grazers preferentially select strains with low enzyme activity when offered prey mixtures. This defence system involves investment in a chemical precursor, DMSP, which is not self-toxic and has other useful metabolic functions. We believe this is the first report of grazing-activated chemical defence in unicellular microorganisms.

Wolfe, Gordon V.; Steinke, Michael; Kirst, Gunter O.

1997-06-01

312

Restoration of the fire-grazing interaction in Artemisia filifolia shrubland  

USGS Publications Warehouse

Patterns of landscape heterogeneity are crucial to the maintenance of biodiversity in shrublands and grasslands, yet management practices in these ecosystems typically seek to homogenize landscapes. Furthermore, there is limited understanding of how the interaction of ecological processes, such as fire and grazing, affects patterns of heterogeneity at different spatial scales. We conducted research in Artemisia filifolia (Asteraceae) shrublands located in the southern Great Plains of North America to determine the effect of restoring the fire-grazing interaction on vegetation structure. Data were collected for 3years in replicated pastures grazed by cattle Bos taurus where the fire-grazing interaction had been restored (fire and grazing=treatment pastures) and in pastures that were grazed but remained unburned (grazing only, no fire=control pastures). The effect of the fire-grazing interaction on heterogeneity (variance) of vegetation structure was assessed at scales from 12??5m 2 to 609ha. Most measurements of vegetation structure within treatment pastures differed from control pastures for 1-3years after being burned but were thereafter similar to the values found in unburned control pastures. Treatment pastures were characterized by a lower amount of total heterogeneity and a lower amount of heterogeneity through time. Heterogeneity of vegetation structure tended to decrease as the scale of measurement increased in both treatment and control pastures. There was deviation from this trend, however, in the treatment pastures that exhibited much higher heterogeneity at the patch scale (mean patch size=202ha) of measurement, the scale at which patch fires were conducted. Synthesis and applications.Vegetation structure in A. filifolia shrublands of our study was readily altered by the fire-grazing interaction but also demonstrated substantial resilience to these effects. The fire-grazing interaction also changed the total amount of heterogeneity characterizing this system, the scale at which heterogeneity in this system was expressed and the amount of heterogeneity expressed through time. Land managers seeking to impose a shifting mosaic of heterogeneity on this vegetation type can do so by restoring the fire-grazing interaction with potential conservation benefits similar to what has been achieved in other ecosystems where historic cycles of disturbance and rest have been restored. ?? 2011 The Authors. Journal of Applied Ecology ?? 2011 British Ecological Society.

Winter, S. L.; Fuhlendorf, S. D.; Goad, C. L.; Davis, C. A.; Hickman, K. R.; Leslie, Jr, D. M.

2012-01-01

313

Sistemas agrossilvipastoris e o aumento da densidade de nutrientes para bovinos em pastejo (Agricultural-forestry-pasture systems and nutrient density increase for grazing cattle)  

Microsoft Academic Search

The agroforestry systems can be used for feed production to cattle promoting the activity sustainabilty. The aspects to be known about these production systems refer to concepts, characteristics and classification of agroforestry systems; the interactions between trees and the other system components, specially the tree and pasture interaction; and notions about agroforestry systems planning, implementation and management. At this revision

Francisco Eden Paiva Fernandes

314

Dairy Cattle Nutrition Home  

NSDL National Science Digital Library

The Pennsylvania State University Department of Dairy and Animal Science provides this site, which contains over 20 full text extension publications (circulars, charts, and tables) in the areas of dairy cattle nutrition, feed management and forage quality. Pertinent slide shows, fourteen nutritional value of forage and concentrate tables, and a growth chart and weight table populate this site. On the lighter side, visitors can download cow images (with explanations of how to turn them into computer wallpaper), and interactive "cow cards" to send to their friends. This is an excellent resource for agricultural extension faculty or agents.

315

Acute heat stress brings down milk secretion in dairy cows by up-regulating the activity of the milk-borne negative feedback regulatory system  

PubMed Central

Background The objective of this study was to determine if acute heat stress (HS) decreases milk secretion by activating the milk-borne negative feedback system, as an emergency physiological response to prevent a life-threatening situation. To induce HS, summer acclimatized dairy cows were exposed to full sun under mid-summer Mediterranean conditions, with and without conventional cooling procedures. Results Exposure to HS induced a rapid and acute (within 24 h) reduction in milk yield in proportion to the heat load. This decrease was moderated by cooler night-time ambient temperature. The reduction in milk yield was associated with corresponding responses in plasminogen activator/plasminogen-plasmin activities, and with increased activity (concentration) of the (1–28) N-terminal fragment peptide that is released by plasmin from ?-casein (?-CN (1–28)). These metabolites constitute the regulatory negative feedback system. Previously, it has been shown that ?-CN (1–28) down-regulated milk secretion by blocking potassium channels on the apical aspects of the mammary epithelial cells. Conclusion Here we demonstrate that the potassium channels in mammary tissue became more susceptible to ?-CN (1–28) activity under HS. Thus, the present study highlighted two previously unreported features of this regulatory system: (i) that it modulates rapidly in response to stressor impact variations; and (ii) that the regulations of the mammary epithelial potassium channel sensitivity to the inhibitory effect of ?-CN (1–28) is part of the regulatory system.

Silanikove, Nissim; Shapiro, Fira; Shinder, Dima

2009-01-01

316

Interactive effects of grazing and burning on wind- and water-driven sediment fluxes: rangeland management implications.  

PubMed

Rangelands are globally extensive, provide fundamental ecosystem services, and are tightly coupled human-ecological systems. Rangeland sustainability depends largely on the implementation and utilization of various grazing and burning practices optimized to protect against soil erosion and transport. In many cases, however, land management practices lead to increased soil erosion and sediment fluxes for reasons that are poorly understood. Because few studies have directly measured both wind and water erosion and transport, an assessment of how they may differentially respond to grazing and burning practices is lacking. Here, we report simultaneous, co-located estimates of wind- and water-driven sediment transport in a semiarid grassland in Arizona, USA, over three years for four land management treatments: control, grazed, burned, and burned + grazed. For all treatments and most years, annual rates of wind-driven sediment transport exceeded that of water due to a combination of ongoing small but nontrivial wind events and larger, less frequent, wind events that generally preceded the monsoon season. Sediment fluxes by both wind and water differed consistently by treatment: burned + grazed > burned > grazed > or = control, with effects immediately apparent after burning but delayed after grazing until the following growing season. Notably, the wind:water sediment transport ratio decreased following burning but increased following grazing. Our results show how rangeland practices disproportionally alter sediment fluxes driven by wind and water, differences that could potentially help explain divergence between rangeland sustainability and degradation. PMID:21516885

Field, Jason P; Breshears, David D; Whicker, Jeffrey J; Zou, Chris B

2011-01-01

317

Controlling internal parasites in grazing ruminants without recourse to anthelmintics: approaches, experiences and prospects.  

PubMed

Interest in ways of raising stock without using anthelmintics has been stimulated by the desire for intensive grazing systems to adopt more sustainable methods of internal parasite control and by potential premiums for "organic" produce. This requires grazing management systems which are practicable and achieve levels of parasite control sufficient to meet realistic production objectives. This paper will summarise 3 years experience of lamb and cattle production without a recourse to anthelmintics on 2 production systems: a mixed cropping, lamb finishing, and cattle rearing unit and an all grass, mixed-stock, hill country unit in which all non-replacement lambs are sold at weaning. On both units parasite control was almost entirely dependent on integrated grazing management of sheep and cattle and strict systems of grazing management had to be rigidly applied. Acceptable productivity could be more readily achieved in sheep than cattle. Rams selected for resistance to nematodes were also used in both sheep flocks. Their influence on lamb production was equivocal. There is a need for more information on factors influencing parasite epidemiology and for consideration of strategies other than alternate grazing. The impact of pasture species on parasite epidemiology needs to be clarified. Current research indicates substantial differences between grasses in terms of parasite burdens acquired and production losses suffered by lambs grazing them. Grazing management may need to vary with pasture species. Also, specialty forage crops, particularly those containing condensed tannins (i.e. Hedysarum coronarium, Lotus pedunculatus and Lotus corniculatus) hold special promise as a means of countering parasite-induced production losses and dagginess. Using biological control of free-living larval stages and vaccination, may in the long term, also prove useful. Developing effective and acceptable systems for raising stock without using anthelmintics presents a considerable challenge, to parasitologists, as well as to plant breeders, agronomists, and farming systems researchers. PMID:8923145

Niezen, J H; Charleston, W A; Hodgson, J; Mackay, A D; Leathwick, D M

1996-01-01

318

75 FR 14564 - Dairy Industry Advisory Committee; Public Meeting  

Federal Register 2010, 2011, 2012, 2013

...AGRICULTURE Farm Service Agency Dairy Industry Advisory Committee; Public Meeting...meeting of the newly established Dairy Industry Advisory Committee (Dairy Committee...review the current state of the dairy industry, discuss current dairy...

2010-03-26

319

Children and Dairy Chemicals  

MedlinePLUS

... alone over a five-year period for caustic farm product ingestion. Astudy of four hospitals in Wisconsin over a ten-year period showed that ten children were admitted for dairy pipeline cleaner ingestion. These injuries are very severe, and since they are entirely ...

320

Dairy Products, 2010 Summary.  

National Technical Information Service (NTIS)

Special Note - Total production by State will no longer be published on an annual basis for the following tables: Yogurt, Total Lowfat Hard Ice Cream, Hard Sherbet, Water and Juice Ices, Sherbet Mix, Frozen Yogurt Mix, and Other Frozen Dairy Products. Ind...

2011-01-01

321

The dynamic North Florida dairy farm model: A user-friendly computerized tool for increasing profits while minimizing N leaching under varying climatic conditions  

Microsoft Academic Search

This paper describes the computer implementation of the Dynamic North Florida Dairy farm model (DyNoFlo Dairy). The DyNoFlo Dairy is a decision support system that integrates nutrient budgeting, crop, and optimization models created to assess nitrogen (N) leaching from North Florida dairy farm systems and the economic impacts resulting from reducing it under different climatic conditions. The decision support system,

Victor E. Cabrera; Norman E. Breuer; Peter E. Hildebrand; David Letson

2005-01-01

322

Seropositivity and risk factors for Brucella in dairy cows in urban and peri-urban small-scale farming in Tajikistan.  

PubMed

In this cross-sectional study, we assessed and mapped the seroprevalence of brucellosis in small-scale dairy farming in an urban and peri-urban area of Tajikistan and investigated factors associated with seropositivity. As urban and peri-urban farming is both an opportunity to improve the livelihood for small-scale farmers and a potential public health hazard, studies are warranted to reveal possible peculiarities in the epidemiology of brucellosis in this type of dairy farming. In total, 904 cows of breeding age belonging to 443 herds in 32 villages were serologically tested with indirect enzyme-linked immunosorbent assay (ELISA) and positive samples confirmed with competitive ELISA. Two logistic regression models were used to investigate an association between seropositivity and risk factors at herd and individual level. The herd and individual seroprevalences were 4.1 and 2.0 %, respectively. Herds with a history of abortions were found to be associated with seropositivity [odds ratio (OR)?=?5.3; 95 % confidence interval (CI), 1.3-21.3]. Large herds with more than eight cattle were more likely to be seropositive compared to smaller herds with one to two cattle (OR?=?13.9; 95 % CI, 1.6-119). The number of calves produced per cow (indicating age) was found to be associated with seropositivity. Younger cows with one to two produced calves were less likely to be seropositive compared to older cows with more than six produced calves (OR?=?0.24; 95 % CI, 0.06-1.0). Neither introduction of new cattle to the herd nor communal grazing was associated with seropositivity. This study shows that infection with Brucella (1) is present in small-scale urban and peri-urban dairy farming in Tajikistan and (2) has significant negative effects on reproductive performance in this farming system and (3) that some previously known risk factors for seropositivity in rural farming system were absent here. PMID:24414248

Lindahl, Elisabeth; Sattorov, Nosirjon; Boqvist, Sofia; Sattori, Izzatullo; Magnusson, Ulf

2014-03-01

323

Dietary cation-anion difference and the health and production of pasture-fed dairy cows 2. Nonlactating periparturient cows.  

PubMed

Anecdotal observations of reduced hypocalcemia due to small reductions in the precalving dietary cation-anion difference (DCAD) are widely reported in Australia and New Zealand. Diets offered to nonlactating, periparturient dairy cows in pasture-based dairy systems in southeastern Australia can vary in their cation-anion difference from 0 to +76 mEq/100 g. The effects of such a range in the DCAD on the health and production of cows, on a pasture-based diet, were examined in an indoor feeding experiment. Four groups of four cows were offered pasture-hay and freshly cut pasture, a periparturient diet typical of that associated with the grazing system in Australia and New Zealand. Varying levels of salt supplementation were used to alter the dietary cation-anion difference, which ranged from -12 to +69 mEq/100 g. Blood and urine pH and mineral concentrations and urine hydroxyproline were measured. The addition of anions to the diet, to produce a negative DCAD, resulted in a nonrespiratory systemic acidosis. With decreasing DCAD, the pH of blood and urine and the strong ion difference of urine decreased curvilinearly, blood bicarbonate decreased linearly and the urinary ratio of Ca to creatinine increased curvilinearly. Although systemic pH was not reduced at a DCAD of +16 mEq/100 g, urine Ca-to-creatinine ratio had begun to rise, probably indicating increased calcium absorption. The absorption and renal excretion of Mg increased with decreasing DCAD. No differences were observed in urine hydroxyproline concentrations and no significant differences in milk production were measured. PMID:12703635

Roche, J R; Dalley, D; Moate, P; Grainger, C; Rath, M; O'Mara, F

2003-03-01

324

Modeling dynamics of circum-arctic tundra plant communities in response to climate warming and grazing pressure  

NASA Astrophysics Data System (ADS)

The Arctic is a complex system with strong interconnectedness among system components. Understanding the responses of the arctic tundra biome to a changing climate requires knowledge of the complex interactions among climate, soils, and the biological system. In this study, we investigate the individual and interactive effects of projected climate change and reindeer/caribou grazing across a variety of climate zones and soil nutrient levels on tundra plant community dynamics using an arctic vegetation model - ArcVeg. Our research questions include: 1) How does soil nutrient availability affect tundra vegetation responses to projected climate warming? 2) How does grazing affect tundra vegetation responses? 3) How do interactions of soil nutrients, climate warming and grazing affect tundra vegetation? We based our simulations on A1B scenario temperature data from the Intergovernmental Panel on Climate Change (IPCC), soil organic nitrogen data from Terrestrial Ecosystem Model (TEM) simulations and grazing pressure derived from reindeer/caribou population data from the CircumArctic Rangifer Monitoring and Assessment Network (CARMA). We found that in general tundra communities responded to warming with increased plant biomass, but the magnitude of the response is affected by the bioclimate zones, warming magnitude, available soil nutrients and grazing pressures. Regions with greater soil organic nitrogen responded to warming with greater biomass increase, Low Arctic tundra tended to have greater biomass increase than High Arctic tundra due to greater shrub abundance. However, such responses are mitigated by grazing. Regions with greater reindeer population and thus greater grazing intensity tended to have stronger negative effects on plant responses to warming than regions with less grazing. For example, in Subzone D, total biomass and NPP increases due to warming were about 71% and 43% in an Alaskan low grazing-intensity region, but 63% and 36% in a northwestern Canada high grazing-intensity region. In Subzone C, although with similar warming magnitude, Yamal and Taymyr region being intensely grazed by reindeer responded with smaller total biomass increase (~68%) than a northwestern Canada low grazing-intensity region (~93%). Plant responses to warming may be a factor that determines the size of reindeer population and understanding how tundra plants respond to warming, grazing and their interactions will contribute to reindeer management practices.

Yu, Q.; Epstein, H. E.; Walker, D. A.; Forbes, B. C.; Vors, L. S.

2011-12-01

325

Genotype by feeding system interaction in the genetic evaluation of Jersey cattle for milk yield.  

PubMed

Results of studies in dairy cattle about the magnitude of the genotype-environment interaction (GEI) are variable, depending on the definitions of genotype and environment. Therefore, the objective of this study was to determine the magnitude of the interaction of genotype and feeding system (confinement and grazing) in the Mexican genetic evaluation of Jersey cattle for milk yield. The number of lactations and animals in the pedigree used were 5122 and 18 432. An animal model and the MTDFREML program were used to estimate genetic parameters and predict genetic values of the animals. Bivariate analysis was carried out considering the performance of confined and grazing cows as two different traits. Three indicator variables were used to assess GEI: (i) magnitude of the genetic correlation coefficients, (ii) correlation between predicted breeding values and (iii) frequency of coincidence in the ranking of top sires. The magnitude of GEI depended on the choice of the indicator variable. The estimate of genetic correlation coefficient less than unity (0.76; P < 0.05) suggested the presence of biologically important GEI. The differences in phenotypic averages and variances between confinement and grazing systems seem to be the main causes for the genotype by environment interaction detected. However, the correlation coefficient between breeding values from confined and grazing animals (0.96) and the frequency of coincidence between breeding values of common sires within the top 100 in confinement and grazing (0.86) indicated low-to-moderate re-ranking of animals or top sires. In addition, the high correlations between predicted breeding values of Mexican genetic evaluation and the two environments (0.99 and 0.93 for confinement and grazing) indicated that for the two feeding systems, breeding values from national analyses could be safely used. PMID:22445370

Ramírez-Valverde, R; Peralta-Aban, J A; Núñez-Domínguez, R; Ruíz-Flores, A; García-Muñiz, J G; García-Peniche, T B

2010-12-01

326

Physiological and behavioral reactions elicited by simulated and real-life visual and acoustic helicopter stimuli in dairy goats  

Microsoft Academic Search

Background  Anecdotal reports and a few scientific publications suggest that flyovers of helicopters at low altitude may elicit fear-\\u000a or anxiety-related behavioral reactions in grazing feral and farm animals. We investigated the behavioral and physiological\\u000a stress reactions of five individually housed dairy goats to different acoustic and visual stimuli from helicopters and to\\u000a combinations of these stimuli under controlled environmental (indoor)

Franz Josef van der Staay; Martin Joosse; Henk van Dijk; Teun Schuurman; Jan van der Meulen

2011-01-01

327

Development and evaluation of equations in the Cornell Net Carbohydrate and Protein System to predict nitrogen excretion in lactating dairy cows.  

PubMed

Nitrogen excretion is of particular concern on dairy farms, not only because of its effects on water quality, but also because of the subsequent release of gases such as ammonia to the atmosphere. To manage N excretion, accurate estimates of urinary N (UN) and fecal N (FN) are needed. On commercial farms, directly measuring UN and FN is impractical, meaning that quantification must be based on predictions rather than measured data. The purpose of this study was to use a statistical approach to develop equations and evaluate the Cornell Net Carbohydrate and Protein System's (CNCPS) ability to predict N excretion in lactating dairy cows, and to compare CNCPS predictions to other equations in the literature. Urinary N was over-predicted by the CNCPS due to inconsistencies in N accounting within the model that partitioned more N to feces than urine, although predicted total N excretion was reasonable. Data to refine model predictions were compiled from published studies (n=32) that reported total collection N balance results. Considerable care was taken to ensure the data included in the development data set (n=104) accounted for >90% of the N intake (NI). Unaccounted N for the compiled data set was 1.47±4.60% (mean ± SD). The results showed that FN predictions could be improved by using a modification of a previously published equation: FN (g/d) = [[NI (g/kg of organic matter) × (1 - 0.842)] + 4.3 × organic matter intake (kg/d)] × 1.20, which, when evaluated against the compiled N balance data, had a squared coefficient of determination based on a mean study effect R(MP)(2) of 0.73, concurrent correlation coefficient (CCC) of 0.83 and a root mean square error (RMSE) of 10.38 g/d. Urinary N is calculated in the CNCPS as the difference between NI and other N excretion and losses. Incorporating the more accurate FN prediction into the current CNCPS framework and correcting an internal calculation error considerably improved UN predictions (RMSE=12.73 g/d, R(MP)(2)=0.86, CCC=0.90). The changes to FN and UN translated into an improved prediction of total manure N excretion (RMSE=12.42 g/d, R(MP)(2)=0.96, CCC=0.97) and allows nutritionists and farm advisors to evaluate these factors during the ration formulation process. PMID:22459846

Higgs, R J; Chase, L E; Van Amburgh, M E

2012-04-01

328

25 CFR 166.409 - How is my grazing rental payment determined?  

Code of Federal Regulations, 2011 CFR

...INTERIOR LAND AND WATER GRAZING PERMITS Grazing Rental Rates, Payments, and Late Payment Collections Rental Payments...The grazing rental payment is the total of the grazing rental rate multiplied by the number of AUMs or acres covered by the...

2011-04-01

329

Ungulate preference for burned patches reveals strength of fire-grazing interaction  

PubMed Central

The interactions between fire and grazing are widespread throughout fire-dependent landscapes. The utilization of burned areas by grazing animals establishes the fire–grazing interaction, but the preference for recently burned areas relative to other influences (water, topography, etc.) is unknown. In this study, we determine the strength of the fire–grazing interaction by quantifying the influence of fire on ungulate site selection. We compare the preference for recently burned patches relative to the influence of other environmental factors that contribute to site selection; compare that preference between native and introduced ungulates; test relationships between area burned and herbivore preference; and determine forage quality and quantity as mechanisms of site selection. We used two large ungulate species at two grassland locations within the southern Great Plains, USA. At each location, spatially distinct patches were burned within larger areas through time, allowing animals to select among burned and unburned areas. Using fine scale ungulate location data, we estimated resource selection functions to examine environmental factors in site selection. Ungulates preferred recently burned areas and avoided areas with greater time since fire, regardless of the size of landscape, herbivore species, or proportion of area burned. Forage quality was inversely related to time since fire, while forage quantity was positively related. We show that fire is an important component of large ungulate behavior with a strong influence on site selection that drives the fire–grazing interaction. This interaction is an ecosystem process that supersedes fire and grazing as separate factors, shaping grassland landscapes. Inclusion of the fire–grazing interaction into ecological studies and conservation practices of fire-prone systems will aid in better understanding and managing these systems.

Allred, Brady W; Fuhlendorf, Samuel D; Engle, David M; Elmore, R Dwayne

2011-01-01

330

Safely Coupling Livestock and Crop Production Systems: How Rapidly Do Antibiotic Resistance Genes Dissipate in Soil following a Commercial Application of Swine or Dairy Manure?  

PubMed

Animal manures recycled onto crop production land carry antibiotic-resistant bacteria. The present study evaluated the fate in soil of selected genes associated with antibiotic resistance or genetic mobility in field plots cropped to vegetables and managed according to normal farming practice. Referenced to unmanured soil, fertilization with swine or dairy manure increased the relative abundance of the gene targets sul1, erm(B), str(B), int1, and IncW repA. Following manure application in the spring of 2012, gene copy number decayed exponentially, reaching background levels by the fall of 2012. In contrast, gene copy number following manure application in the fall of 2012 or spring of 2013 increased significantly in the weeks following application and then declined. In both cases, the relative abundance of gene copy numbers had not returned to background levels by the fall of 2013. Overall, these results suggest that under conditions characteristic of agriculture in a humid continental climate, a 1-year period following a commercial application of raw manure is sufficient to ensure that an additional soil burden of antibiotic resistance genes approaches background. The relative abundance of several gene targets exceeded background during the growing season following a spring application or an application done the previous fall. Results from the present study reinforce the advisability of treating manure prior to use in crop production systems. PMID:24632259

Marti, Romain; Tien, Yuan-Ching; Murray, Roger; Scott, Andrew; Sabourin, Lyne; Topp, Edward

2014-05-01

331

25 CFR 166.400 - Who establishes grazing rental rates?  

Code of Federal Regulations, 2011 CFR

...rental rates? 166.400 Section 166.400 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER GRAZING PERMITS Grazing Rental Rates, Payments, and Late Payment Collections Rental Rate Determination and...

2011-04-01

332

25 CFR 166.305 - When is grazing capacity determined?  

Code of Federal Regulations, 2011 CFR

... Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER GRAZING PERMITS Land and Operations Management § 166.305 When is grazing capacity determined? Before we grant, modify, or approve a permit, in consultation...

2011-04-01

333

INFLUENCE OF PROTOZOAN GRAZING ON CONTAMINANT BIODEGRADATION. (R825418)  

EPA Science Inventory

The influence of protozoan grazing on biodegradation rates in samples from contaminated aquifer sediment was evaluated under aerobic and anaerobic conditions. Predator¯prey biomass ratios suggested that protozoan grazing might be influencing bacterial populations....

334

43 CFR 4130.5 - Free-use grazing permits.  

Code of Federal Regulations, 2013 CFR

...conformance with the requirements of this part; (2) The primary purpose of grazing use is for scientific research or administrative studies; or (3) The primary purpose of grazing use is the control of noxious weeds. [43 FR...

2013-10-01

335

Determinants of technical efficiency among dairy farms in Wisconsin.  

PubMed

The US dairy sector is facing structural changes including a geographical shift in dairy production and a tendency toward the implementation of more intensive production systems. These changes might significantly affect farm efficiency, profitability, and the long-term economic sustainability of the dairy sector, especially in more traditional dairy production areas. Consequently, the goal of this study was to examine the effect of practices commonly used by dairy farmers and the effect of intensification on the performance of the farms. We used a sample of 273 Wisconsin dairy farms to estimate a stochastic production frontier simultaneously with a technical inefficiency model. The empirical analysis showed that at a commercial level the administration of bovine somatotropin hormone to lactating cows increased milk production. In addition, we found that production exhibits constant returns to scale and that farm efficiency is positively related to farm intensification, the level of contribution of family labor in the farm activities, the use of a total mixed ration feeding system, and milking frequency. PMID:20059937

Cabrera, V E; Solís, D; del Corral, J

2010-01-01

336

GRAZING ON PUBLIC LANDS IN THE 21ST CENTURY  

Microsoft Academic Search

A panel of professionals from the ranching, environmental, agency, and university communities was assembled to examine trends relating to the future of grazing on federal lands. Five factors were identified that were thought to influence the use of grazed forages over the next 20 years. These factors were (1) multiple uses of public land, (2) public sentiment towards grazing on

Larry W. Van Tassell; L. Allen Torell; Neil R. Rimbey

2001-01-01

337

Grazing angle microscopy - A new technique for surface analysis  

Microsoft Academic Search

Grazing angle spectroscopy (GAS) has been extended to microscopic sampling areas by a special objective lens and an FT-IR research microscope. While the advantages of grazing incidence for the study of thin films on metals has been known and applied since the mid-1960s, GAS measurements have been limited to samples with large smooth flat surfaces. The grazing angle microscope objective

J. A. Reffner; W. T. Wihlborg; M. C. Sweeney

1992-01-01

338

Does extensive grazing benefit butterflies of coastal dunes?  

Microsoft Academic Search

Grazing at low stocking rates has become a common management practice in nature restoration projects in the Netherlands. However, detailed knowledge of grazing impact is often poor, in particular for invertebrates. This study addressed the impact of extensive grazing on butterflies. Butterflies are critical indicators of habitat quality for many plant and animal species. We compared monitoring data from 1992

M. F. Wallis De Vries; Ivo Raemakers

2001-01-01

339

Behavior Responses of Dairy Cows Trained to Activate a Feeding Device1  

Microsoft Academic Search

Operant conditioning procedures (food reward immediately following a desired response) seldom have been ap- plied to the study of learning ability in dairy cattle, and yet they offer the dairy researcher unique opportunities to study and control important behavioral re- sponses. The method provides the animal with a means of communicating with the control system, a system for the setting

C. L. Moore; W. G. Whittlestone; M. Mullord; P. N. Priest; R. Kilgour; J. L. Albright

1975-01-01

340

DairyWise, a whole-farm dairy model.  

PubMed

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. PMID:17954774

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

341

The Gratifications of Grazing: Why Flippers Flip.  

ERIC Educational Resources Information Center

An exploratory study focused on usage patterns of television remote control devices (RCDs), examining how and why individuals use television RCDs to "graze." The study identified the gratifications obtained from RCD use and evaluated their relative importance in accounting for variations in RCD use. Subjects were 455 undergraduates in…

Walker, James R.; Bellamy, Robert V., Jr.

342

Delineating Grazing: Observations of Remote Control Use.  

ERIC Educational Resources Information Center

States that contrary to previous reports of "grazing," most viewers only used their remote control devices (RCDs) once or twice every half hour. Claims that the dominant RCD operation was direct channel punching, as opposed to dial turning. Concludes that most RCD activity did not take place during a program, thus voiding industry concerns over…

Eastman, Susan Tyler; Newton, Gregory D.

1995-01-01

343

25 CFR 168.8 - Grazing fees.  

Code of Federal Regulations, 2011 CFR

...holders of interim permits, will be determined, and assessed by the Area Director and paid in accordance with 25 U.S.C. 640d-15. (b) The Hopi Tribe has established an annual grazing fee to be assessed all range users on Hopi Partitioned...

2011-04-01

344

Birdshooting, lead pellets, and grazing cattle  

Microsoft Academic Search

Blood samples from cattle grazing near an area of intense birdshooting were analyzed for lead by atomic absorption spectrophotometry. No difference in lead blood levels could be demonstrated between heifers in the birdshooting pasture and the control heifers, not even during the dry summer of 1981 when there was little grass, which should have facilitated the uptake of lead pellets

H. Bjørn; N. Gyrd-Hansen; Inge Kraul

1982-01-01

345

Neutron Reflectivity and Grazing Angle Diffraction.  

National Technical Information Service (NTIS)

Over the past 10 years, neutron reflectivity has emerged as a powerful technique for the investigation of surface and interfacial phenomena in many different fields. In the paper, a short review of some of the work on neutron reflectivity and grazing-angl...

J. F. Ankner C. F. Majkrzak S. K. Satija

1993-01-01

346

A theoretical study of the acoustic impedance of orifices in the presence of a steady grazing flow  

NASA Technical Reports Server (NTRS)

An analysis of the oscillatory fluid flow in the vicinity of a circular orifice with a steady grazing flow is presented. The study is similar to that of Hersh and Rogers but with the addition of the grazing flow. Starting from the momentum and continuity equations, a considerably simplified system of partial differential equations is developed with the assumption that the flow can be described by an oscillatory motion superimposed upon the known steady flow. The equations are seen to be linear in the region where the grazing flow effects are dominant, and a solution and the resulting orifice impedance are presented for this region. The nonlinearity appears to be unimportant for the usual conditions found in aircraft noise suppressors. Some preliminary conclusions of the study are that orifice resistance is directly proportional to grazing flow velocity (known previously from experimental data) and that the orifice inductive (mass reactance) end correction is not a function of grazing flow. This latter conclusion is contrary to the widely held notion that grazing flow removes the effect of the orifice inductive end correction. This conclusion also implies that the experimentally observed total inductance reduction with grazing flow might be in the flow within the orifice rather than in the end correction.

Rice, E. J.

1976-01-01

347

Epidemiology of gastrointestinal nematodes in cattle on traditional, small-scale dairy and large-scale dairy farms in Iringa district, Tanzania.  

PubMed

A longitudinal study was carried out to determine the prevalence, distribution and intensity of gastrointestinal (GI) nematodes in traditional, small-scale dairy and large-scale dairy cattle farms in Iringa district, Southern highlands of Tanzania. Coprological examination of cohorts for GI nematode eggs in faeces, tracer worm counts and pasture larval counts were performed monthly for 1 year. Results indicated that the type of management, especially the grazing habit has a significant influence on the prevalence and intensity of GI nematodes. The predominant nematodes were Cooperia spp. (51.6%), Oesophagostomum radiatum (35.7%) and Haemonchus placei (10.2%). The worm burden in tracers was mainly composed of Cooperia spp. (83%) in large-scale dairy farms, while O. radiatum was dominant (60.8%) in traditional farms. Faecal egg counts (FEC) and tracer worm counts were generally low and FEC peaked only in calves and weaners/yearlings. Adults and all age groups in small-scale dairy farms had very low FEC throughout the year. Pasture larval counts, FEC and tracer worm counts peaked towards the end of the rainy season. Based on conditions of the study area, farmers could save substantial amount of money through strategic treatments as opposed to the previous routine of treating the whole herd at least four times a year. Strategic treatments are recommended in calves and weaners only in traditional and large-scale dairy farms. Strategic treatment of adults and small-scale dairy cattle might be not necessary. Strategic treatments at the end of the rainy/early dry season (May/June) and at the end of the dry/early rainy season (November/December) are recommended in the district. An additional treatment against GI nematodes in calves during the mid rainy season (February/March) might be important. PMID:15710529

Keyyu, J D; Kyvsgaard, N C; Monrad, J; Kassuku, A A

2005-02-28

348

Development of Adjustable Grazing Incidence Optics  

NASA Astrophysics Data System (ADS)

We report on the development of adjustable grazing incidence optics. We are developing bimorph mirrors for high resolution (sub-arc second) imaging. Bimorph mirrors consist of a thin layer of piezo-electric material deposited on the back surface of a thin (< 0.4 mm) thermally formed glass or electroplated metal segmented mirror. Voltage applied across the thickness of the piezo produces a strain in the plane of the mirror surface. The strain produces bending of the mirror similar to the bi-metallic effect. No reaction structure is necessary, which allows one to densely nest mirror shells for large effective area. A pixilated array of outer electrodes on the piezo material localizes the strain to the particular piezo "pixel.” Mirror figure errors are corrected (on-orbit) via induced localized deformations. We have successfully deposited a 1-micrometer thick layer of the piezo-electric material lead-zirconate-titanate (PZT) on thin glass mirrors. We report on the electrical and mechanical properties of the bimorph mirrors, and mirror requirements. We discuss finite element modeling of bimorph mirrors. In particular, we focus on how a difference in mirror mounting affects the influence functions ( the induced deformations). We are also developing the use of electrostrictive adjusters for moderate resolution (a few arc second) imaging. Electroplated nickel/cobalt full shells are mounted together using the adjusters. The adjusters are arrayed axially and tangentially between shells, with their adjustable dimension in the radial direction. Each shell is adjusted and fixed in place during mirror assembly, starting with the innermost shell. We review finite element modeling of the adjustable optics and the application of the adjustment system to correct manufacturing errors. We discuss initial tests using electrostrictive adjusters to change the shape of flat mirror segments. This work is supported by NASA Contract NNX09AE87G and a grant from the Gordon and Betty Moore Foundation.

Reid, Paul B.; Davis, W.; Schwartz, D. A.; Trolier-McKinstry, S.; Wilke, R. H. T.

2010-02-01

349

Spherical mirror grazing incidence x-ray optics  

NASA Technical Reports Server (NTRS)

An optical system for x-rays combines at least two spherical or near spherical mirrors for each dimension in grazing incidence orientation to provide the functions of a lens in the x-ray region. To focus x-ray radiation in both the X and the Y dimensions, one of the mirrors focusses the X dimension, a second mirror focusses the Y direction, a third mirror corrects the X dimension by removing comatic aberration and a fourth mirror corrects the Y dimension. Spherical aberration may also be removed for an even better focus. The order of the mirrors is unimportant.

Cash, Jr., Webster C. (Inventor)

1997-01-01

350

BEEF SPECIES SYMPOSIUM: An assessment of the 1996 Beef NRC: Metabolizable protein supply and demand and effectiveness of model performance prediction of beef females within extensive grazing systems.  

PubMed

Interannual variation of forage quantity and quality driven by precipitation events influence beef livestock production systems within the Southern and Northern Plains and Pacific West, which combined represent 60% (approximately 17.5 million) of the total beef cows in the United States. The beef cattle requirements published by the NRC are an important tool and excellent resource for both professionals and producers to use when implementing feeding practices and nutritional programs within the various production systems. The objectives of this paper include evaluation of the 1996 Beef NRC model in terms of effectiveness in predicting extensive range beef cow performance within arid and semiarid environments using available data sets, identifying model inefficiencies that could be refined to improve the precision of predicting protein supply and demand for range beef cows, and last, providing recommendations for future areas of research. An important addition to the current Beef NRC model would be to allow users to provide region-specific forage characteristics and the ability to describe supplement composition, amount, and delivery frequency. Beef NRC models would then need to be modified to account for the N recycling that occurs throughout a supplementation interval and the impact that this would have on microbial efficiency and microbial protein supply. The Beef NRC should also consider the role of ruminal and postruminal supply and demand of specific limiting AA. Additional considerations should include the partitioning effects of nitrogenous compounds under different physiological production stages (e.g., lactation, pregnancy, and periods of BW loss). The intent of information provided is to aid revision of the Beef NRC by providing supporting material for changes and identifying gaps in existing scientific literature where future research is needed to enhance the predictive precision and application of the Beef NRC models. PMID:24398839

Waterman, R C; Caton, J S; Löest, C A; Petersen, M K; Roberts, A J

2014-07-01

351

Generalized aspergillosis in dairy sheep.  

PubMed

Two cases of systemic aspergillosis are described in dairy sheep from a flock in which fungal mastitis appeared subsequent to the antibiotic treatment of animals before parturition. Lesions characterized by necrosis and a pyogranulomatous exudate were observed in the mammary glands, supramammary and mediastinal lymph nodes, kidneys, lung, liver, heart, forestomachs and brain. The intense vasculitis with thrombosis observed in various organs, but especially in the mammary glands, suggested a haematogenous dissemination of the infection from this organ. The aetiological diagnosis was accomplished by the immunohistochemical staining of the fungal structures seen in the histological sections by the specific Aspergillus monoclonal antibody Mab-WF-AF-1 together with the isolation of Aspergillus fumigatus in pure culture from affected tissues. PMID:10605371

Pérez, V; Corpa, J M; Gar?ia Marín, J F; Adúriz, J J; Jensen, H E

1999-11-01

352

Iron fortification in dairy industry  

Microsoft Academic Search

Iron deficiency is usually the result of insufficient dietary intake of iron, poor utilization of iron from ingested food, or a combination of the two. Direct addition of iron to milk or dairy products might be an effective mean of increasing the dietary intake of iron to the general population. However, iron fortification of milk or dairy products induces several

Frédéric Gaucheron

2000-01-01

353

A comprehensive dairy valorization model.  

PubMed

Dairy processors face numerous challenges resulting from both unsteady dairy markets and some specific characteristics of dairy supply chains. To maintain a competitive position on the market, companies must look beyond standard solutions currently used in practice. This paper presents a comprehensive dairy valorization model that serves as a decision support tool for mid-term allocation of raw milk to end products and production planning. The developed model was used to identify the optimal product portfolio composition. The model allocates raw milk to the most profitable dairy products while accounting for important constraints (i.e., recipes, composition variations, dairy production interdependencies, seasonality, demand, supply, capacities, and transportation flows). The inclusion of all relevant constraints and the ease of understanding dairy production dynamics make the model comprehensive. The developed model was tested at the international dairy processor FrieslandCampina (Amersfoort, the Netherlands). The structure of the model and its output were discussed in multiple sessions with and approved by relevant FrieslandCampina employees. The elements included in the model were considered necessary to optimally valorize raw milk. To illustrate the comprehensiveness and functionality of the model, we analyzed the effect of seasonality on milk valorization. A large difference in profit and a shift in the allocation of milk showed that seasonality has a considerable impact on the valorization of raw milk. PMID:23200469

Banaszewska, A; Cruijssen, F; van der Vorst, J G A J; Claassen, G D H; Kampman, J L

2013-02-01

354

Usual Intake of Total dairy  

Cancer.gov

Usual Intake of Total dairy Table A33. Total dairy: Means, percentiles and standard errors of usual intake, 2007-2010 Age (Years) N1 cup equivalents3 Mean (SE)2 5% (SE) 10% (SE) 25% (SE) 50% (SE) 75% (SE) 90% (SE) 95% (SE) Males 1-3 774 2.5 (0.07) 1.0

355

Invited review: Sustainability of the US dairy industry.  

PubMed

The US dairy industry has realized tremendous improvements in efficiencies and milk production since the 1940s. During this time, farm and total cow numbers have decreased and average herd size has increased. This intensification, combined with the shift to a largely urban public, has resulted in increased scrutiny of the dairy industry by social and environmental movements and increased concern regarding the dairy industry's sustainability. In response to these concerns, a group of scientists specializing in animal welfare, nutrient management, greenhouse gas emissions, animal science, agronomy, agricultural engineering, microbiology, and economics undertook a critical review of the US dairy industry. Although the US dairy system was identified as having significant strengths, the consensus was that the current structure of the industry lacks the resilience to adapt to changing social and environmental landscapes. We identified several factors affecting the sustainability of the US dairy industry, including climate change, rapid scientific and technological innovation, globalization, integration of societal values, and multidisciplinary research initiatives. Specific challenges include the westward migration of milk production in the United States (which is at odds with projected reductions in precipitation and associated limitations in water availability for cattle and crops), and the growing divide between industry practices and public perceptions, resulting in less public trust. Addressing these issues will require improved alignment between industry practices and societal values, based upon leadership from within the industry and sustained engagement with other interested participants, including researchers, consumers, and the general public. PMID:23831089

von Keyserlingk, M A G; Martin, N P; Kebreab, E; Knowlton, K F; Grant, R J; Stephenson, M; Sniffen, C J; Harner, J P; Wright, A D; Smith, S I

2013-09-01

356

Impacts of cattle grazing on spatio-temporal variability of soil moisture and above-ground live plant biomass in mixed grasslands  

NASA Astrophysics Data System (ADS)

Areas with relatively high spatial heterogeneity generally have more biodiversity than spatially homogeneous areas due to increased potential habitat. Management practices such as controlled grazing also affect the biodiversity in grasslands, but the nature of this impact is not well understood. Therefore this thesis studies the impacts of variation in grazing on soil moisture and biomass heterogeneity. These are not only important in terms of management of protected grasslands, but also for designing an effective grazing system from a livestock management point of view. This research is a part of the cattle grazing experiment underway in Grasslands National Park (GNP) of Canada since 2006, as part of the adaptive management process for restoring ecological integrity of the northern mixed-grass prairie region. An experimental approach using field measurements and remote sensing (Landsat) was combined with modelling (CENTURY) to examine and predict the impacts of grazing intensity on the spatial heterogeneity and patterns of above-ground live plant biomass (ALB) in experimental pastures in a mixed grassland ecosystem. The field-based research quantified the temporal patterns and spatial variability in both soil moisture (SM) and ALB, and the influence of local intra-seasonal weather variability and slope location on the spatio-temporal variability of SM and ALB at field plot scales. Significant impacts of intra-seasonal weather variability, slope position and grazing pressure on SM and ALB across a range of scales (plot and local (within pasture)) were found. Grazing intensity significantly affected the ALB even after controlling for the effect of slope position. Satellite-based analysis extended the scale of interest to full pastures and the surrounding region to assess the effects of grazing intensity on the spatio-temporal pattern of ALB in mixed grasslands. Overall, low to moderate grazing intensity showed increase in ALB heterogeneity whereas no change in ALB heterogeneity over time was observed for heavy grazing intensity. All grazing intensities showed decrease in spatial range (patch size) over time indicating that grazing is a patchy process. The study demonstrates that cattle grazing with variable intensity can maintain and change the spatial patterns of vegetation in the studied region. Using a modelling approach, the relative degrees to which grazing intensity and soil properties affect grassland productivity and carbon dynamics at longer time-periods were investigated. Both grass productivity and carbon dynamics are sensitive to variability in soil texture and grazing intensity. Moderate grazing is predicted to be the best option in terms of maintaining sufficient heterogeneity to support species diversity, as well as for carbon management in the mixed grassland ecosystem.

Virk, Ravinder

357

Reproductive performance of lactating dairy cows managed for first service using timed artificial insemination with or without detection of estrus using an activity-monitoring system.  

PubMed

Lactating dairy cows (n=1,025) on a commercial dairy farm were randomly assigned at 10±3d in milk (DIM) to 1 of 3 treatments for submitting cows to first artificial insemination (AI) and were fitted with activity-monitoring tags (Heatime; SCR Engineers Ltd., Netanya, Israel) at 24±3 DIM. Cows (n=339) in treatment 1 were inseminated based on increased activity from the end of the voluntary waiting period (50 DIM) until submission to an Ovsynch protocol; cows without increased activity from 21 to 65 DIM began an Ovsynch protocol at 65±3 DIM, whereas cows without increased activity from 21 to 50 DIM but not from 51 to 79 DIM began an Ovsynch protocol at 79±3 DIM. Cows (n=340) in treatment 2 were inseminated based on activity after the second PGF2? injection of a Presynch-Ovsynch protocol at 50 DIM, and cows without increased activity began an Ovsynch protocol at 65±3 DIM. Cows (n=346) in treatment 3 were monitored for activity after the second PGF2? injection of a Presynch-Ovsynch protocol, but all cows received timed AI (TAI) at 75±3 DIM after completing the Presynch-Ovsynch protocol. The activity-monitoring system detected increased activity in 56, 69, and 70% of cows in treatments 1, 2, and 3, respectively. Treatment-2 cows had the fewest average days to first AI (62.5), treatment-3 cows had the most average days to first AI (74.9), and treatment-1 cows had intermediate average days to first AI (67.4). Treatment-1 and -2 cows in which inseminations occurred as a combination between increased activity and TAI had fewer overall pregnancies per AI (P/AI) 35d after AI (32% for both treatments) compared with treatment-3 cows, all of which received TAI after completing the Presynch-Ovsynch protocol (40%). Based on survival analysis, although the rate at which cows were inseminated differed among treatments, treatment did not affect the proportion of cows pregnant by 300 DIM. Thus, use of an activity-monitoring system to inseminate cows based on activity reduced days to first AI, whereas cows receiving 100% TAI after completing a Presynch-Ovsynch protocol had more P/AI. The trade-off between AI service rate and P/AI in the rate at which cows became pregnant was supported by an economic analysis in which the net present value ($/cow per year) differed by only $4 to $8 among treatments. We conclude that a variety of strategies using a combination of AI based on increased activity using an activity-monitoring system and synchronization of ovulation and TAI can be used to submit cows for first AI. PMID:24630667

Fricke, P M; Giordano, J O; Valenza, A; Lopes, G; Amundson, M C; Carvalho, P D

2014-05-01

358

Dairy-cattle health in Gyeongnam, Korea.  

PubMed

An animal-health monitoring system in the Gyeongnam area was started in 1997 to develop statistically valid data for use in estimating disease frequencies in dairy cattle, and the associated costs. The objectives of this study were to: (1) describe what was done to implement and maintain the system in Gyeongnam; (2) present selected disease frequencies; (3) discuss the epidemiological consideration of what was done and implications for results obtained. Veterinary medical officers (VMOs), comprising professors and graduate students from Gyeongsang National University, faculty of Gyeongnam Livestock Promotion Institute and clinic veterinarians, served as data collectors. After training on current disease and management problems of dairy cattle, interview techniques, sampling methods and data-collection instruments, the VMOs participated in selection of the sample herds and data gathering. Forty (n=40) of 167 dairy herds were selected randomly using a computer-generated list of random numbers and the VMOs visited farms once in a month for 12 months to collect data about management, disease, inventory, production, preventive treatment, financial and other relevant data. Strict data-quality control devices were used. Specific feed-back was developed for the producers and data collectors. The six disorders found most frequently in cows (from the highest to the lowest) were breeding problems, clinical mastitis, birth problems, gastrointestinal problems, metabolic problems and lameness. In young stock, respiratory, multiple system, breeding and gastrointestinal problems were predominant, whereas in calves, gastrointestinal, respiratory and integumental problems predominated. PMID:11679173

Jong, S K; Gong, S K; Chung, H K; Dae, S H

2001-12-01

359

The use of a geographic information system to identify a dairy goat farm as the most likely source of an urban Q-fever outbreak  

Microsoft Academic Search

BACKGROUND: A Q-fever outbreak occurred in an urban area in the south of the Netherlands in May 2008. The distribution and timing of cases suggested a common source. We studied the spatial relationship between the residence locations of human cases and nearby small ruminant farms, of which one dairy goat farm had experienced abortions due to Q-fever since mid April

Barbara Schimmer; Ronald ter Schegget; Marjolijn Wegdam; Lothar Züchner; Arnout de Bruin; Peter M Schneeberger; Thijs Veenstra; Piet Vellema; Wim van der Hoek

2010-01-01

360

Pregnancy, Bovine Somatotropin, and Dietary n-3 Fatty Acids in Lactating Dairy Cows: I. Ovarian, Conceptus, and Growth Hormone–Insulin-Like Growth Factor System Responses  

Microsoft Academic Search

The objective was to examine effects of bovine soma- totropin (bST), pregnancy, and dietary fatty acids on reproductive responses in lactating dairy cows. Begin- ning at approximately 17 d in milk (DIM), a comparison was made of isoenergetic diets comprising supplemen- tary lipids of whole cottonseed vs. calcium salts of fish oil enriched lipid (FO). Ovulation was synchronized in cows

T. R. Bilby; A. Sozzi; M. M. Lopez; F. T. Silvestre; A. D. Ealy; C. R. Staples; W. W. Thatcher

2006-01-01

361

Simulation of Long-Term Carbon and Nitrogen Dynamics in Grassland-Based Dairy Farming Systems to Evaluate Mitigation Strategies for Nutrient Losses  

PubMed Central

Many measures have been proposed to mitigate gaseous emissions and other nutrient losses from agroecosystems, which can have large detrimental effects for the quality of soils, water and air, and contribute to eutrophication and global warming. Due to complexities in farm management, biological interactions and emission measurements, most experiments focus on analysis of short-term effects of isolated mitigation practices. Here we present a model that allows simulating long-term effects at the whole-farm level of combined measures related to grassland management, animal housing and manure handling after excretion, during storage and after field application. The model describes the dynamics of pools of organic carbon and nitrogen (N), and of inorganic N, as affected by farm management in grassland-based dairy systems. We assessed the long-term effects of delayed grass mowing, housing type (cubicle and sloping floor barns, resulting in production of slurry and solid cattle manure, respectively), manure additives, contrasting manure storage methods and irrigation after application of covered manure. Simulations demonstrated that individually applied practices often result in compensatory loss pathways. For instance, methods to reduce ammonia emissions during storage like roofing or covering of manure led to larger losses through ammonia volatilization, nitrate leaching or denitrification after application, unless extra measures like irrigation were used. A strategy of combined management practices of delayed mowing and fertilization with solid cattle manure that is treated with zeolite, stored under an impermeable sheet and irrigated after application was effective to increase soil carbon stocks, increase feed self-sufficiency and reduce losses by ammonia volatilization and soil N losses. Although long-term datasets (>25 years) of farm nutrient dynamics and loss flows are not available to validate the model, the model is firmly based on knowledge of processes and measured effects of individual practices, and allows the integrated exploration of effective emission mitigation strategies.

Shah, Ghulam Abbas; Groot, Jeroen C.J.; Shah, Ghulam Mustafa; Lantinga, Egbert A.

2013-01-01

362

Effect of naturally occurring nematode infections on growth performance of first-season grazing calves.  

PubMed

Liveweight of calves on 89 dairy farms was measured at the end of the grazing season and related per herd to the level of exposure to nematode infection during the grazing season. There were significant between-herd variations in antibody titres against Ostertagia spp., Cooperia spp. and Dictyocaulus viviparus as well as in pepsinogen values. All but six herds (93.1%) had gastrointestinal nematode infections, as measured by faecal egg counts in September. Faecal samples of 17 herds (19.3%) contained lungworm larvae in September. Liveweight of calves per herd deviated from -68.1 kg to +84.1 kg from the age-adjusted population mean after their first grazing season. Growth performance up to the time of liveweight measurements was significantly correlated negatively with several serological and parasitological parameters. Data could be fitted by means of both linear and segmented curvilinear regression. Antibody titre against Cooperia spp. and gastrointestinal nematode egg output measured in September accounted for 3.1% (P less than 0.10) and 6.7% (P less than 0.05), respectively, of the variation in growth performance among herds. Certain infection parameters, when combined, accounted for 9.2% of this variation; these were antibody titre against Cooperia spp. and larval counts for both gastrointestinal nematodes and lungworm. Adding certain management factors to these infection parameters resulted in a model explaining 27.6% of the observed variation in growth performance among herds. These factors were supplementary feeding, lungworm vaccination, anthelmintic treatment at housing, date of housing and herd age. PMID:2353424

Ploeger, H W; Kloosterman, A; Eysker, M; Borgsteede, F H; van Straalen, W; Verhoeff, J

1990-04-01

363

25 CFR 166.307 - Will the grazing capacity be increased if I graze adjacent trust or non-trust rangelands not...  

Code of Federal Regulations, 2011 CFR

... Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER GRAZING PERMITS Land and Operations Management § 166.307 Will the grazing capacity be increased if I graze adjacent trust or non-trust rangelands not covered...

2011-04-01

364

Recapturing nutrients from dairy waste using biochar  

NASA Astrophysics Data System (ADS)

Biochar or biomass derived black carbon is known to be highly resistant to decomposition with half-life periods ranging from hundreds of years to millennia. It is also reported to enhance soil productivity due to high nutrient retention and favorable effects on soil pH, water retention capacity as well as microbial population. Brazilian Terra Preta soils have shown the potential of biochar for long-term carbon sequestration capacity and productivity of soil and many researchers have now focused on utilizing this phenomenon to create fertile, carbon-rich soils, called Terra Preta Nova. Although the highly adsorptive nature of biochar is well characterized, the potential for using biochar in environmental cleanup efforts is relatively unexplored. Dairy waste is a source of significant water pollution because it introduces excess nutrients such as phosphates and nitrates into the soil and water system. Since many soils have limited capacity to retain nitrate and phosphate, especially for long periods of time, the utility of dairy waste manure to enhance soil fertility and nutrient availability to plants is limited. Here, we present results from a project that we started to determine the potential of biochar to recover the excess nutrients from dairy flushed manure. In this initial study, a commercially available biochar amendment was ground and used in a batch sorption experiment with the dairy flushed manure from a local dairy in Merced, California. Four manure dilutions viz. 10, 25, 50 and 100%, and three shaking times, viz. 1, 12 and 24 hours were used for this study. We then calculated the amount of ammonia, nitrate and phosphate adsorbed by the biochar using differences in nutrient concentrations before and after the sorption experiment. Biochar showed significant capacity of adsorbing these nutrients, suggesting a potential for controlling the dairy pollution. The resulting enriched biochar can potentially act as a slow release fertilizer and enhance soil productivity as well as increasing the long-term carbon sequestration potential of soils. We are currently initiating further research to determine the desorption potenial of the biochar sorbed nutrients in soil.

Sarkhot, D.; Ghezzehei, T. A.; Berhe, A. A.

2009-12-01

365

Mass transfer coefficients of ammonia for liquid dairy manure  

NASA Astrophysics Data System (ADS)

Available data indicate that 75-80% of total nitrogen entering a dairy operation is lost as ammonia (NH3) via manure storage systems such as anaerobic lagoons. Direct measurement of NH3 emissions from manure holding systems can be complicated and expensive; however, process-based emission models can provide a cost-effective alternative for estimating NH3 emissions. The overall NH3 mass transfer coefficient (KOL) is an important component of any NH3 emission process-based model. Models relying purely on theoretically-derived mass transfer coefficients have not adequately predicted NH3 emissions from livestock manure, and these values are lacking in general for liquid dairy manure handling systems. To provide critically needed KOL data for dairy facilities, this study directly measured NH3 loss from dilute dairy manure slurries placed in a laboratory convective emission chamber to determine realistic NH3KOL values under conditions typically experienced in the Pacific Northwest. The KOL values increased as liquid temperature and air velocity increased and decreased as air temperature and total solids content increased, exhibiting an overall range of 1.41 × 10-6-3.73 × 10-6 m s-1. These values were then used to develop a non-linear empirical model of KOL for dilute dairy manure slurries (R2 = 0.83). The KOL exhibited sensitivity to the four model parameters considered in descending order: liquid manure temperature, ambient air temperature, wind or air velocity, and total solids concentration. The suite of KOL values applicable to liquid dairy manure and the establishment of an empirical model that yields accurate KOL estimates under a range of conditions for use in process-based models provide valuable tools for predicting NH3 emissions from dairy operations.

Vaddella, Venkata K.; Ndegwa, Pius M.; Ullman, Jeffrey L.; Jiang, Anping

2013-02-01

366

76 FR 8998 - Dairy Industry Advisory Committee; Public Meeting  

Federal Register 2010, 2011, 2012, 2013

...AGRICULTURE Farm Service Agency Dairy Industry Advisory Committee; Public Meeting...announces a public meeting of the Dairy Industry Advisory Committee (Dairy Committee...on policy issues impacting the dairy industry. Instructions regarding...

2011-02-16

367

75 FR 54085 - Dairy Industry Advisory Committee; Public Meeting  

Federal Register 2010, 2011, 2012, 2013

...AGRICULTURE Farm Service Agency Dairy Industry Advisory Committee; Public Meeting...announces two public meetings of the Dairy Industry Advisory Committee (Dairy Committee...on policy issues impacting the dairy industry. Instructions regarding...

2010-09-03

368

75 FR 26710 - Dairy Industry Advisory Committee; Public Meeting  

Federal Register 2010, 2011, 2012, 2013

...AGRICULTURE Farm Service Agency Dairy Industry Advisory Committee; Public Meeting...the second public meeting of the Dairy Industry Advisory Committee (Dairy Committee...policy, hear proposals from the dairy industry, and hear public comments....

2010-05-12

369

75 FR 72785 - Dairy Industry Advisory Committee; Public Meeting  

Federal Register 2010, 2011, 2012, 2013

...AGRICULTURE Farm Service Agency Dairy Industry Advisory Committee; Public Meeting...announces meetings of the Dairy Industry Advisory Committee (Dairy Committee...on policy issues impacting the dairy industry. We invite you to attend...

2010-11-26

370

76 FR 4611 - Dairy Industry Advisory Committee; Public Meeting  

Federal Register 2010, 2011, 2012, 2013

...AGRICULTURE Farm Service Agency Dairy Industry Advisory Committee; Public Meeting...announces a public meeting of the Dairy Industry Advisory Committee (Dairy Committee...on policy issues impacting the dairy industry. Instructions regarding...

2011-01-26

371

A process-based model of ammonia emissions from dairy cows: improved temporal and spatial resolution  

NASA Astrophysics Data System (ADS)

This research has developed an integrated model of a dairy farm that predicts monthly ammonia emission factors based on farming practices and climate conditions, including temperature, wind speed, and precipitation. The model can be used to predict the seasonal and geographic variations in ammonia emission factors, which are important for accurately predicting aerosol nitrate concentrations. The model tracks the volume of manure and mass of ammoniacal nitrogen as the manure moves through the housing, storage, application, and grazing stages of a dairy farm. Most of the processes of ammonia volatilization are modeled explicitly, but poorly understood processes are parameterized and tuned to match empirical data. The tuned model has been compared to independent experimental data and is shown to be robust over the range of experimental conditions. We have characterized the differences in emissions resulting from changes in climate conditions and farming practices and found that both of these factors are significant and should be included when developing a national inventory.

Pinder, Robert W.; Pekney, Natalie J.; Davidson, Cliff I.; Adams, Peter J.

372

Neutron reflectivity and grazing angle diffraction  

SciTech Connect

Over the past 10 years, neutron reflectivity has emerged as a powerful technique for the investigation of surface and interfacial phenomena in many different fields. In the paper, a short review of some of the work on neutron reflectivity and grazing-angle diffraction as well as a description of the current and planned neutron reflectometers at NIST is presented. Specific examples of the characterization of magnetic, superconducting, and polymeric surfaces and interfaces are included.

Ankner, J.F.; Majkrzak, C.F.; Satija, S.K.

1993-01-01

373

Field Demonstration of the Performance of a Geotube Dewatering System to Reduce Phosphorus and Other Substances from Dairy Lagoon Effluent.  

National Technical Information Service (NTIS)

This report outlines the performance of a Geotube dewatering system which was introduced for evaluation by the Miratech Division of Ten Cate Nicolon and General Chemical Corporation. This system uses a chemical pre-treatment to coagulate the solids from t...

2006-01-01

374

Sustainability, arid grasslands and grazing: New applications for technology  

SciTech Connect

The study of ecology is taking on increasing global importance as the value of well-functioning ecosystems to human well-being becomes better understood. However, the use of technological systems for the study of ecology lags behind the use of technologies in the study of other disciplines important to human well-being, such as medicine, chemistry and physics. The authors outline four different kinds of large-scale data needs required by land managers for the development of sustainable land use strategies, and which can be obtained with current or future technological systems. They then outline a hypothetical resource management scenario in which data on all those needs are collected using remote and in situ technologies, transmitted to a central location, analyzed, and then disseminated for regional use in maintaining sustainable grazing systems. They conclude by highlighting various data-collection systems and data-sharing networks already in operation.

Pregenzer, A.L.; Parmenter, R.; Passell, H.D.; Budge, T.; Vande Caste, J.

1999-12-08

375

76 FR 26930 - Dairy Promotion and Research Program; Importer Nominations to the Dairy Promotion and Research Board  

Federal Register 2010, 2011, 2012, 2013

...representation on the Dairy Board was mandated by the 2002 amendments to the Dairy Act. The Dairy Board is authorized to design programs to strengthen the dairy industry's position in domestic and foreign markets. The program is financed by...

2011-05-10

376

Atmospheric Ammonia Emissions from a Dairy  

NASA Astrophysics Data System (ADS)

Gaseous ammonia (NH3) emissions at high concentrations can damage human and animal respiratory systems. NH3 environmental impacts include aerosol formation, altering atmospheric chemistry, terrestrial and aquatic eutrophication, soil acidification and global warming. Preindustrial NH3 emissions are estimated to be 21 Tg yr-1 while current emissions are estimated to be 47 Tg yr-1 with most of the increase coming from domestic animals (Galloway et al., 1995). There is a lack of detailed emission data from the United States and there are many problems with applying emissions estimates from Europe due to the difference in farming practices between the two regions. Feed and manure management practices can have a large impact on emissions. We are studying NH3 emissions at the WSU dairy located near Pullman, WA to provide a detailed emission inventory of the various sources at the dairy. The dairy has approximately 170 milking cows housed in open air barns and the waste from the milking cows is stored in liquid slurry lagoons until it is applied to grass fields in the late summer. NH3 is measured using a short-path spectroscopic absorption near 200 nm with a sensitivity of a few ppbv and a time resolution of a few seconds. The open air short-path method is advantageous because it is self calibrating and avoids inlet wall adherence which is a major problem for most NH3 measurement techniques. As part of the detailed emission inventory, NH3 fluxes were determined from the milking stalls, main slurry lagoon and the application of slurry to the fields with a large sprinkler using a SF6 tracer technique and a dense point Gaussian plume model. NH3 emission fluxes from various parts of the dairy will be presented.

Rumburg, B. P.; Filipy, J. M.; Bays, J.; Mount, G. H.; Yonge, D.; Lamb, B. K.; Johnson, K.; Kincaid, R.

2002-12-01

377

High Grazing Angle and High Resolution Sea Clutter: Correlation and Polarisation Analyses  

Microsoft Academic Search

Spatial and temporal correlations of high grazing angle high resolution sea clutter collected by the DSTO Ingara polarimetric X-band system are studied. It seems that wavelengths of wind waves and swells are retrievable from the range correlation whereas the periods of the waves and swells are recoverable from the azimuthal correlation. The polarimetric behaviour of sea clutter is also studied,

Yunhan Dong

378

Dairy and Dairy Alternatives: Media Portrayal vs. Nutritional Facts  

Microsoft Academic Search

Many people use dairy alternatives in their everyday lives. In particular, society’s emphasis on low-fat, low-cal nutrition has created a huge desire for something other than milk in cereal, ice-cream, coffee etc., but are these alternatives actually healthier? In this project, I will examine the media portrayal of three major dairy alternatives, soy-milk, almond-milk, and rice-milk, and whether the nutritional

Megan Stinson

2012-01-01

379

Continuous feral horse grazing and grazing exclusion in mountain pampean grasslands in Argentina  

NASA Astrophysics Data System (ADS)

This paper evaluates changes in the composition and structure of plant communities and plant functional groups associated with the continuous presence of feral horses in mountain pampean grasslands in Argentina in order to explore the potential effects of horse removal on vegetation restoration. Specific and functional richness, diversity, evenness, spatial heterogeneity and above-ground biomass were compared between areas subjected to ten years of intensive grazing by horses and exclosures of the same age. Forbs, shrubs and rosettes were more abundant after ten years of grazing, while the spatial heterogeneity of perennial grasses was higher in long-term grazed areas. Nevertheless, grasslands showed good recovery after horse removal, with greater species diversity and evenness, higher abundance of perennial grasses, greater above-ground biomass and lower percentages of exotic species. An understanding of the effect of feral animals on plant communities will lead to the design of a strategy of adaptive management and monitoring tools for measuring the condition of grasslands.

de Villalobos, A. E.; Zalba, S. M.

2010-09-01

380

Effect of Restricted Grazing Time on the Foraging Behavior and Movement of Tan Sheep Grazed on Desert Steppe  

PubMed Central

To investigate the effect of restricted grazing time on behavior of Tan sheep on desert steppe, forty 4-months old male Tan sheep with an original body weight (BW) of 15.62±0.33 kg were randomly allocated to 4 grazing groups which corresponded to 4 different restricted grazing time treatments of 2 h/d (G2), 4 h/d (G4), 8 h/d (G8) and 12 h/d (G12) access to pasture. The restricted grazing times had a significant impact on intake time, resting time, ruminating time, bite rate and movement. As the grazing time decreased, the proportion of time spent on intake, bite rate and grazing velocity significantly (p<0.05) increased, but resting and ruminating time clearly (p<0.05) decreased. The grazing months mainly depicted effect on intake time and grazing velocity. In conclusion, by varying their foraging behavior, Tan sheep could improve grazing efficiency to adapt well to the time-limited grazing circumstance.

Chen, Yong; Luo, Hailing; Liu, Xueliang; Wang, Zhenzhen; Zhang, Yuwei; Liu, Kun; Jiao, Lijuan; Chang, Yanfei; Zuo, Zhaoyun

2013-01-01

381

Technical note: Data loggers are a valid method for assessing the feeding behavior of dairy cows using the Calan Broadbent Feeding System.  

PubMed

Assessing feeding behavior is important in understanding the effects of nutrition and management on the well-being of dairy cows. Historically, collection of these data from cows fed with a Calan Broadbent Feeding System (American Calan Inc., Northwood, NH) required the labor-intensive practices of direct observation or video review. The objective of this study was to evaluate the agreement between the output of a HOBO change-of-state data logger (Onset Computer Corp., Bourne, MA), mounted to the door shell and latch plate, and video data summarized with continuous sampling. Data (number of feed bin visits per day and feeding time in minutes per day) were recorded with both methods from 26 lactating cows and 10 nonlactating cows for 3 d per cow (n=108). The agreement of the data logger and video methods was evaluated using the REG procedure of SAS to compare the mean response of the methods against the difference between the methods. The maximum allowable difference (MAD) was set at ±3 for bin visits and ±20 min for feeding time. Ranges for feed bin visits (2 to 140 per d) and feeding time (28 to 267 min/d) were established from video data. Using the complete data set, agreement was partially established between the data logger and video methods for feed bin visits, but not established for feeding time. The complete data set generated by the data logger was screened to remove visits of a duration ?3 s, reflecting a cow unable to enter a feed bin (representing 7% of all data) and ?5,400 s, reflecting a failure of the data logger to align properly with its corresponding magnetic field (representing <1% of all data). Using the resulting screened data set, agreement was established for feed bin visits and feeding time. For bin visits, 4% of the data was beyond the MAD. For feeding time, 3% of the data was beyond the MAD and 74% of the data was ±1 min. The insignificant P-value, low coefficient of determination, and concentration of the data within the MAD indicate the agreement of the change-of-state data logger and video data. This suggests the usage of a change-of-state data logger to assess the feeding behavior of cows feeding from a Calan Broadbent Feeding System is appropriate. Use of the screening criteria for data analysis is recommended. PMID:22818459

Krawczel, P D; Klaiber, L M; Thibeau, S S; Dann, H M

2012-08-01

382

Grazing affects essential oil compositions of Artemisia sieberi Besser.  

PubMed

This study was conducted in order to study the effect of grazing on quality and quantity of Artemisia sieberi essential oil in Kerman province of Iran. Vegetation sites of Artemisia sieberi under three grazing intensity (heavy, moderate and non-grazed) with the same ecological conditions were selected based on distance of water resource and nomad tent in Khabre National Park and near rangelands. Within each sits, two individual plants sampled at random in full flowering stage. The oils were obtained by hydrodistillation of air-dried samples and were analyzed by GC-MS. The main constituents of oils were as follows: non-grazed site; 1,8cineol (29.9%), myrcene (14.1%), moderate grazed site; myrcene (15.9%), 1,8cineol (15.1%), Eudesm-7(11)-en-4-ol (11.1%) and heavy grazed site; 4-tepinyl acetate (23.3%), davanone (21.9%), p-cymene (19%). PMID:19069870

Bagheri, R; Chaichi, M R; Mohseni-Saravi, M; Amin, G R; Zahedi, G

2007-03-01

383

The effect of rapid rural industry changes on the development of a decision support system for dairy farmers in Australia  

Microsoft Academic Search

This paper outlines the factors that affected the development of a knowledge based decision support system (KBDSS) during a period of rapid industry change. The development process was led by a steering committee consisting of farmers, extension officers and milk processor representatives. The committee requested that changes be made to the KBDSS as a response to different circumstances in the

Don Kerr; Heidi Winklhofer

2006-01-01

384

Comparative productivity and grazing behaviour of Huacaya alpacas and Peppin Merino sheep grazed on annual pastures  

Microsoft Academic Search

Adult Huacaya alpaca (mixed sex, mean±S.D., age 5.2±2.7 years, live weight 72.0±9.5kg) were grazed with Peppin Merino sheep (castrated male, age 3±0.1 years, live weight 54.0±3.9kg) for 2 years on improved annual pasture at commercial grazing pressures (10–17 dry sheep equivalents\\/ha) near Melbourne, Australia. Alpacas and sheep gained weight during the first year and then lost weight (proportional loss: alpacas

B. A McGregor

2002-01-01

385

Implications of restricted access to grazing by cattle in wet season in the Sahel  

Microsoft Academic Search

To address the problem of restricted access to grazing by cattle in wet season in the Sahel, a grazing trial was conducted to study the effect of duration of grazing and grazing method on cattle nutrition and performance. Twenty-four intact steers weighing 259kg (SD=62) were randomly allotted to four treatments to study the effect of the combination of grazing method

A. A. Ayantunde; S. Fernández-Rivera; P. H. Hiernaux; R. Tabo

2008-01-01

386

Hydrogeologic controls on water quality at a university dairy farm  

NASA Astrophysics Data System (ADS)

Dairy farms typically produce large quantities of manure and other waste products which are often stored or treated in lagoons and then applied to local fields as fertilizer. Contamination of nearby streams by dairy farm wastes through surface runnoff, drainage tile discharge, direct release of wastes or inundation of waste storage facilities during seasonal flooding have long been recognized as major environmental concerns. However, much less attention has been paid to fate and transport of dairy wastes in the subsurface and their potential impact on water quality in aquifers or in groundwater discharge to streams. One of the challenges in evaluating the environmental impact of dairy operations is that there are relatively few field research sites where all of the potential pathways for waterborne transport of dairy wastes are monitored and quantititatively evaluated. There are even fewer sites where extensive baseline water quality monitoring programs were established prior to operation of the dairy. This is essential to distinguish between environmental impacts from dairy operations and other nearby sources, such as beef production and human sewage from septic fields. This talk describes the development of a an integrated hydrogeologic/hydrologic site assessment and groundwater/surface water quality monitoring program at the University of Tennessee - Little River Dairy Farm, located near Townsend, TN. The dairy is currently under construction and the first cows are expected to arrive in late 2010. Hydrologic/hydrogeologic investigations of streams and groundwater at the site have been underway for more than 3 years, and these are expected to provide background data for assessing impacts of dairy wastes and for testing the effectiveness of different management practises. The lower half of the ~180 ha site consists of low-relief fields used for row crops, which are underlain by 4 - 8 m of alluvial deposits (mainly interbedded silt and fine-grained sands) on top of by black shale or limestone. Several active sinkholes are present in the portion of the fields underlain by limestone. The fields are bounded on two sides by the Little River, a popular recreational river, and on the third side by Ellejoy Creek, which is on the state’s 303(d) list for impairment by nutrients, sediment and fecal microorganisms, which are derived from upstream agricultural and rural residential development. These fields will be fertilized with treated dairy wastes and are the main area of concern for offsite migration of contaminants through groundwater, drainage ditches and (eventually) a tile drain system. A secondary area of concern is the dairy waste treatment pond which is located, along with the dairy barns, on the upland portion of the site, which is underlain by 1-2 m of clay-rich residual soils developed on fractured shale bedrock. Long term water quality monitoring of runnoff, streams, drainage ditches and groundwater is planned, with the intent of measuring environmental impact of dairy operations and testing the effectiveness of different management practises.

McKay, L. D.; Hunter, R. W.; Lee, J.

2010-12-01

387

Gastrointestinal parasites presence during the peripartum decreases total milk production in grazing dairy Holstein cows  

Microsoft Academic Search

Parasitism in cattle is known to impair growth and development. Recent findings suggest that productivity of adult animals is also affected, but little is known about the physiological mechanisms involved. Furthermore, development of nematode resistance to drugs makes imperative the search of management practices that avoid whole herd treatment. We undertook an epidemiological and endocrine study in a grass based

A. F. Perri; M. E. Mejía; N. Licoff; L. Lazaro; M. Miglierina; A. Ornstein; D. Becu-Villalobos; I. M. Lacau-Mengido

2011-01-01

388

Biological soil crusts exhibit a dynamic response to seasonal rain and release from grazing with implications for soil stability  

USGS Publications Warehouse

In Northern Mexico, long-term grazing has substantially degraded semiarid landscapes. In semiarid systems, ecological and hydrological processes are strongly coupled by patchy plant distribution and biological soil crust (BSC) cover in plant-free interspaces. In this study, we asked: 1) how responsive are BSC cover/composition to a drying/wetting cycle and two-year grazing removal, and 2) what are the implications for soil erosion? We characterized BSC morphotypes and their influence on soil stability under grazed/non-grazed conditions during a dry and wet season. Light- and dark-colored cyanobacteria were dominant at the plant tussock and community level. Cover changes in these two groups differed after a rainy season and in response to grazing removal. Lichens with continuous thalli were more vulnerable to grazing than those with semi-continuous/discontinuous thalli after the dry season. Microsites around tussocks facilitated BSC colonization compared to interspaces. Lichen and cyanobacteria morphotypes differentially enhanced resistance to soil erosion; consequently, surface soil stability depends on the spatial distribution of BSC morphotypes, suggesting soil stability may be as dynamic as changes in the type of BSC cover. Longer-term spatially detailed studies are necessary to elicit spatiotemporal dynamics of BSC communities and their functional role in biotically and abiotically variable environments. ?? 2009 Elsevier Ltd.

Jimenez, Aguilar, A.; Huber-Sannwald, E.; Belnap, J.; Smart, D. R.; Arredondo, Moreno, J. T.

2009-01-01

389

Reproductive performance of crossbred dairy cows reared under traditional low input production system in the eastern Himalayas  

Microsoft Academic Search

Reproductive performance of crossbred cows reared under traditional low input production system was assessed. A total number\\u000a of 160 farmers were surveyed and traditional fodders were evaluated for proximate composition. Total protein, albumin and\\u000a cholesterol concentrations in blood serum were analyzed. The age at first service, age at first calving, calving interval,\\u000a calving to first service and calving to conception

A. Kumaresan; P. P. Prabhakaran; K. M. Bujarbaruah; K. A. Pathak; Bijoy Chhetri; S. K. Ahmed

2009-01-01

390

Enhancing the profitability of pasture-based dairy production in the humid tropics through improved nutrition.  

PubMed

Dairy production in the tropics represents a major challenge, especially when reliant on grazed forages, because of the conflicting factors of a high nutritional demand to sustain lactation on the one hand, and the relatively low quality of tropical grasses and a stressful environment, on the other. This paper focuses primarily on those tropical situations where grazed pasture is the cheapest feed resource. Effective management of the pasture as well as the animals that graze it is required in order to maximize economic viability of the farming enterprise. Feed planning helps to ensure that pasture use is maximized, either directly by grazing or, where profitable, indirectly by cutting for conservation. High rates of pasture utilization at each grazing minimize pasture senescence and decay and ensure that pasture remains in a vegetative state of the highest possible nutritional quality. Total annual feed requirements of the grazing herd must therefore be matched as closely as possible to the total annual pasture production on the farm. Stocking rate is critical in this regard, and is the single most important determinant of productivity in pastoral farming. Periods of pasture surplus or deficit will inevitably arise, but can be minimized by matching the monthly feed requirements of the herd as closely as possible to the monthly feed production on the farm. Herd requirements can be influenced, for example, through altering calving patterns and drying off dates. Even with good pasture management practices, it is highly likely that tropical pasture quality will be low for part of the year. Utilization of low-quality forages can be improved through the appropriate use of feed supplements, and the key principles are discussed. Firstly, conditions for optimum fermentative digestion in the rumen must be promoted through adequate provision of fermentable energy and nitrogen as well as essential minerals, such as phosphorus and sulfur. Further supplementation with metabolizable energy or protein, depending on what limits animal production, may be profitable. Various practical supplementation strategies for tropical forages are discussed. Finally, some suggestions for future research and development for enhancing the profitability of pasture-based dairy production in the humid tropics are made. PMID:10081794

van Houtert, M F; Sykes, A R

1999-01-27

391

The grazing preference of sheep is related to prior experience.  

PubMed

Background - The annual pasture legume Casbah biserrula (Biserrula pelecinus L.) is moderately palatable to sheep relative to other species but, in the field, sheep often avoid biserrula and select other plants. We hypothesised that the preference of sheep for biserrula is influenced by their prior grazing experience. Objective - To determine the preference of sheep for biserrula after they had experienced grazing pastures with different proportions of biserrula. Design - Five groups of 10 Merino hoggets grazed for four weeks pastures sown with i) 100% biserrula, ii) 100% crimson clover, iii) 100% annual ryegrass, iv) 50% biserrula and 50% annual ryegrass or v) 50% crimson clover and 50% annual ryegrass. Each group then grazed randomized monoculture rows of biserrula, crimson clover and annual ryegrass and their preference was calculated from pasture samples that were taken from paired sites before and after grazing. The pastures were grazed at the vegetative, reproductive and senesced phases of growth by a new group of hoggets each time. Outcomes - The preference of sheep for biserrula at the vegetative and reproductive phases of growth was influenced by their previous grazing history, but not after senescence. Conclusions - Sheep that have grazed a biserrula dominant pasture can develop an aversion to biserrula at the vegetative and reproductive phases of growth. This may explain why sheep eat other plants late in the growing season. Sheep grazing a pasture with a low proportion of biserrula are less likely to develop an aversion and may continue to eat biserrula. PMID:15023649

Thomas, D T; Milton, J TB; Ewing, M A; Revell, C K; Lindsay, D R

2003-11-01

392

Moisture, Density, and Porosity Changes as Dairy Manure is Biodried  

Microsoft Academic Search

The initial functioning of a biodrying process on an 85 cow dairy farm in the New York City (NYC) Watershed is described. This system started operation in the fall of 2001. The startup challenges and preliminary operational data on the forced air system, and establishing a procedure for processing the manure are described. The objective is to use the heat

Peter Wright; Scott Inglis

393

Terraced Pasture for Disposal of Dairy Yard Runoff.  

National Technical Information Service (NTIS)

An alternative system of handling and disposing of milking barn wastewater and feedlot runoff water was evaluated for three years. This system was established on a 50-cow dairy farm in South Carolina and consisted of utilizing a pasture areas downslope fr...

R. O. Hegg C. L. Barth V. L. Quisenberry W. H. Livingston

1982-01-01

394

Rheological Characterisation of Dairy Emulsions For Cold Foam Applications  

Microsoft Academic Search

Dairy foams are complex aerated materials where the liquid matrix is an emulsion made by oil droplets dispersed in a water system. An innovative application of these systems leads to an interesting product derived from instant whipped creams that are stored and consumed at low temperatures (typically between??4 and??18°C) like an ice cream. This novel product requires a specific texture

Domenico Gabriele; Massimo Migliori; Noemi Baldino; Rosa Di Sanzo; Bruno de Cindio; Daniela Vuozzo

2011-01-01

395

International genetic evaluations for feed intake in dairy cattle through the collation of data from multiple sources.  

PubMed

Feed represents a large proportion of the variable costs in dairy production systems. The omission of feed intake measures explicitly from national dairy cow breeding objectives is predominantly due to a lack of information from which to make selection decisions. However, individual cow feed intake data are available in different countries, mostly from research or nucleus herds. None of these data sets are sufficiently large enough on their own to generate accurate genetic evaluations. In the current study, we collate data from 10 populations in 9 countries and estimate genetic parameters for dry matter intake (DMI). A total of 224,174 test-day records from 10,068 parity 1 to 5 records of 6,957 cows were available, as well as records from 1,784 growing heifers. Random regression models were fit to the lactating cow test-day records and predicted feed intake at 70d postcalving was extracted from these fitted profiles. The random regression model included a fixed polynomial regression for each lactation separately, as well as herd-year-season of calving and experimental treatment as fixed effects; random effects fit in the model included individual animal deviation from the fixed regression for each parity as well as mean herd-specific deviations from the fixed regression. Predicted DMI at 70d postcalving was used as the phenotype for the subsequent genetic analyses undertaken using an animal repeatability model. Heritability estimates of predicted cow feed intake 70d postcalving was 0.34 across the entire data set and varied, within population, from 0.08 to 0.52. Repeatability of feed intake across lactations was 0.66. Heritability of feed intake in the growing heifers was 0.20 to 0.34 in the 2 populations with heifer data. The genetic correlation between feed intake in lactating cows and growing heifers was 0.67. A combined pedigree and genomic relationship matrix was used to improve linkages between populations for the estimation of genetic correlations of DMI in lactating cows; genotype information was available on 5,429 of the animals. Populations were categorized as North America, grazing, other low input, and high input European Union. Albeit associated with large standard errors, genetic correlation estimates for DMI between populations varied from 0.14 to 0.84 but were stronger (0.76 to 0.84) between the populations representative of high-input production systems. Genetic correlations with the grazing populations were weak to moderate, varying from 0.14 to 0.57. Genetic evaluations for DMI can be undertaken using data collated from international populations; however, genotype-by-environment interactions with grazing production systems need to be considered. PMID:24731627

Berry, D P; Coffey, M P; Pryce, J E; de Haas, Y; Løvendahl, P; Krattenmacher, N; Crowley, J J; Wang, Z; Spurlock, D; Weigel, K; Macdonald, K; Veerkamp, R F

2014-06-01

396

[Continuous ecopathological survey. 2. Typology of dairy cattle farms with high and low fertility].  

PubMed

Management characteristics were analysed in two groups of dairy herds (20 to 60 cows per herd) during a continuous eco-pathological survey, in relation to high and low fertility. 59.8% of the cows from the eleven high fertility herds were successfully inseminated at first service and 11.4% of the cows inseminated for the first time more than 40 days post-partum required 3 or more services. The corresponding values were 51.1 and 25.6% for the ten low fertility herds. Other reproductive criteria (calving-first service interval, disturbed oestrus cycles), which more depend on the reproduction management, were not different between the two groups. Feeding system greatly varied in the low fertility group. Frequent changes in diet composition, a longer period of "green" forages distribution (crucifers, grass silage) as well as less utilisation of concentrates are some of the reasons which can explain the low fertility. Calving occurred mainly from February to April in low fertility herds, at the transition from winter diets to grazing. Milk production was lower, 4 580 kg per cow and per year vs 5 520 kg for high fertility group. Milk production falls were more frequent and Holstein semen was less used. Tied housing conditions, and higher incidence of Fasciola hepatica and abomasal mematodes characterised low fertility herds; inversely, the clinical pathology appeared to be less frequent in this group. Soil manganese concentration was lower (16.3 ppm) in the low fertility group as compared to the other group (30.9 ppm); this could be explained by less schistose rocks where the low fertility farms are localized. In conclusion, the risk factors associated with low fertility may be attributed to: the composite system of feeding in addition to the use of "green" forages, a lack of proper programming with regards to the season of calving, and the high frequency of parasitic infestations, with special reference to liver fluke. PMID:6660819

Barnouin, J; Paccard, P; Fayet, J C; Brochart, M; Bouvier, A

1983-01-01

397

SLOPE PROFILOMETRY OF GRAZING INCIDENCE OPTICS.  

SciTech Connect

Profiling instruments are well-suited to the measurement of grazing incidence optics, such as those found in synchrotron radiation beam lines. Slope measuring profilers, based upon the principle of the pencil beam interferometer, have proven to be especially useful in measuring the figure and slope errors on cylindrical aspheres. The Long Trace Profiler, in various configurations, is the most widely used of this class of profiler. Current performance provides slope measurement accuracy at the microradian level and height measurements accurate to 25 nm over 1 meter trace lengths.

TAKACS,P.Z.

2003-01-14

398

Failure to eradicate the lungworm Dictyocaulus viviparus on dairy farms by a single mass-treatment before turnout.  

PubMed

On two dairy farms it was attempted to eradicate lungworm, Dictyocaulus viviparus, by means of a single mass-treatment of all cattle that had been grazed the previous year(s), before turnout in the spring. Both farms experienced two years of lungworm outbreaks in the adult dairy herd prior to this study. Following confirmation that both herds contained lungworm carriers, all animals older than approximately 6 months were treated with eprinomectin in March 2007. One week after treatment none of the animals were shedding lungworm larvae. Subsequently, animals were pastured according to normal farm routine. From August to November all first-calving heifers were coprologically and serologically monitored for lungworm infection. During 2007 both farms remained lungworm-negative and did not report any clinical sign indicative for a lungworm infection. The following year, on one of the farms replacements grazing on cow pastures, started showing signs of parasitic bronchitis which was serologically confirmed. The other herd remained free of parasitic bronchitis until at least the fourth year after the mass treatment, although some coughing was noticed in 2008 among first-lactation heifers. It was concluded that a single mass-treatment before the grazing season may be useful to break a series of annual lungworm outbreaks. However, it is not a secure method to prevent parasitic bronchitis for more than one year. PMID:22079553

Ploeger, H W; Holzhauer, M

2012-04-30

399

43 CFR 4130.6-1 - Exchange-of-use grazing agreements.  

Code of Federal Regulations, 2013 CFR

... Exchange-of-use grazing agreements. 4130.6-1 Section 4130.6-1 Public Lands: Interior Regulations Relating to...ADMINISTRATION-EXCLUSIVE OF ALASKA Authorizing Grazing Use § 4130.6-1 Exchange-of-use grazing...

2013-10-01

400

25 CFR 161.400 - What are the criteria for reissuing grazing permits?  

Code of Federal Regulations, 2011 CFR

...grazing permits? 161.400 Section 161.400 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER NAVAJO PARTITIONED LANDS GRAZING PERMITS Reissuance of Grazing Permits § 161.400 What are the criteria for...

2011-04-01

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