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1

Effects of stocking rate, supplementation, genotype and their interactions on grazing dairy systems: a review  

Microsoft Academic Search

The main effects of, and the interactions between, stocking rate (SR), supplementation and genotype on dry matter (DM) intake, herbage utilisation, milk production and profitability of grazing dairy systems have been reviewed. The SR determines the average herbage allowance (HA) per cow and therefore has a major effect on herbage intake (HI) and on the productivity of grazing dairy systems.

J. Baudracco; N. Lopez-Villalobos; CW Holmes; KA Macdonald

2010-01-01

2

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

3

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

4

Subclinical ketosis in dairy cows: prevalence and risk factors in grazing production system.  

PubMed

The purpose of this study was to estimate the prevalence of Subclinical ketosis (SCK) between 4 and 19 days in milk (DIM) in a grazing production system and investigate the importance of potential risk factors for SCK. This cross-sectional study was conducted in dairy cows (n = 107), which had more of two parities. The concentration of ?-hydroxybutyric (BHB) in blood was quantified through a hand-held meter. Potential risk factors evaluated were calving interval (CI), milk yield in previous lactation, metritis, dystocia, calf sex (male), parity (?3 vs. ?4) and pre-partum body condition score (BCS ? 3.5 vs. ?3.75). Prevalence of SCK was 10.3% (95% CI 4.7-15) between 4 and 19 DIM. Risk factors identified were the occurrence of both metritis and pre-partum BCS ? 3.75. Cows with metritis had 4.9 (95% CI 1.17-20.98) times more risk of developing SCK than cows without metritis. And the cows with pre-partum BCS ? 3.75 had 5.25 (95% CI 1.32-21.11) times more risk of developing SCK than cows with pre-partum BCS ? 3.5. Metritis could induce a lower feed intake and promote the development of SCK. High pre-partum BCS could induce a greater mobilization of body reserves altering liver function and aggravating post-partum NEB. The results are indicative of the expected prevalence of SCK in grazing production system. Factors associated could help to identify cattle at risk of SCK and improve the management of strategies to limit the effects. PMID:24236545

Garro, C J; Mian, L; Cobos Roldán, M

2014-10-01

5

Effect of silage from ryegrass intercropped with winter or common vetch for grazing dairy cows in small-scale dairy systems in Mexico.  

PubMed

The objective was to determine the effect of including silages of annual ryegrass (Lolium multiflorum) intercropped with winter vetch (Vicia villosa) (ARG-VV) or with common vetch (Vicia sativa) (ARG-VS) compared with maize silage (MS) on milk yield and milk composition of dairy cows grazing cultivated perennial ryegrass-white clover pastures with supplemented concentrate during the dry season. Six Holstein dairy cows with a mean yield of 19.0 kg/cow/day at the beginning of the experiment were randomly assigned to a 3?×?3 repeated Latin square. Treatments were: 8 h/day intensive grazing, 3.6 kg of dry matter (DM) per cow per day of concentrate plus MS, and ARG-VV or ARG-VS ad libitum at a stocking rate of 3.0 cows/ha for three experimental periods of 3 weeks each. Milk yield (MY) and milk composition, live weight and body condition score as well as silage and concentrate intakes were recorded during the third week of each experimental period, and pasture intake was estimated indirectly from utilised metabolisable energy. Economic analysis was obtained by preparing partial budgets. There were no statistical differences (P?>?0.10) in MY, milk fat or protein content nor for live weight, but there was significant difference (P?grazed herbage intake whilst no differences for total DM intake. Slightly higher economic returns (10%) were obtained with ARG-VS over MS, and this was 7% higher than ARG-VV. It is concluded that ARG-VS could be an option for complementing grazing for small-scale dairy production systems in the dry season as it is comparable to MS in animal performance and slightly better in economic terms. PMID:21327716

Hernández-Ortega, Martha; Heredia-Nava, Darwin; Espinoza-Ortega, Angelica; Sánchez-Vera, Ernesto; Arriaga-Jordán, Carlos M

2011-06-01

6

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

7

Is there a need for different genetics in dairy grazing systems?  

Technology Transfer Automated Retrieval System (TEKTRAN)

The decline in cow fertility has had a negative impact on all dairy producers, especially those that practise seasonal calving with pasture-based dairying. One alternative that is being tried in the United States by a few graziers who are interested in improved fertility is to use bulls from New Zea...

8

Dietary Preference of Dairy Cows Grazing Ryegrass and White Clover  

Microsoft Academic Search

Thedietarypreferenceoflactatingdairycowsgrazing perennialryegrass(LoliumperenneL.)andwhiteclover (Trifolium repens L.) was studied. Twelve groups of 2 lactating, Holstein-Friesian dairy cows grazed 1.2-ha plots containing conterminal monocultures of clover and grass. Half of the groups grazed a plot containing 75% clover and 25% grass (by ground area), with the remaining groups grazing a plot containing 25% clover and 75% grass. The intake rates of clover were

S. M. Rutter; R. J. Orr; N. H. Yarrow; R. A. Champion

2004-01-01

9

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

PubMed

Structural development in the prime sector has led to increasing herd sizes and new barn systems, followed by less summer grazing for dairy cows in Denmark. Effects of grazing on single welfare measures in dairy cows - for example, the presence of integument alterations or mortality - have been studied under different conditions. However, the effect of grazing on welfare, conceptualised as the multidimensional physical and mental state of the animal, has not yet been studied in contemporary cubicle loose-housing systems. The aim of our study was to investigate, based on a Welfare Quality® inspired multidimensional dairy cow welfare assessment protocol, the within-herd effect of summer grazing compared with winter barn housing in Danish dairy herds with cubicle free-stall systems for the lactating cows. Our hypothesis was that cow welfare in dairy herds was better during summer grazing than during full-time winter housing. Furthermore, we expected improved welfare with an increase in daily summer grazing hours. In total, 41 herds have been visited once in the winter and once in the summer of 2010 to assess their welfare status with 17 different animal- and resource-based welfare measures. A panel of 20 experts on cattle welfare and husbandry evaluated the relative weight of the 17 welfare measures in a multidimensional assessment scheme. They estimated exact weights for a priori constituted severe compared with moderate scores of welfare impairment concerning each measure, as well as relevance of the measures in relation to each other. A welfare index (WI; possible range 0 to 5400) was calculated for each herd and season with a higher index indicating poorer welfare. The within-herd comparison of summer grazing v. winter housing considered all the 17 measures. The mean WI in summer was significantly lower (better) than in winter (mean 2926 v. 3330; paired t-test P = 0.0001) based on a better state of the integument, claw conformation and better access to water and food. Body condition and faeces consistence were worse in summer. Many daily grazing hours (range average above 3 to 9 h) turned out to be more beneficial than few daily grazing hours (range average above 9 to 21 h) for the welfare of the dairy herds. In conclusion, this study reports a positive within-herd effect of summer grazing on dairy cow welfare, where many daily grazing hours were more beneficial than few daily grazing hours. PMID:23244468

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

2013-05-01

10

Rotational grazing of dairy cows : effect of grazing intervals on animal and grass production  

E-print Network

Rotational grazing of dairy cows : effect of grazing intervals on animal and grass production F grass of good value : this method enhances animal performance but reduces grass production. Inversely, according to Frame and Hunt, (1971, J Br Grassld Soc, 2, 163-171) and Binnie and Chestnutt (1991, Grass

Paris-Sud XI, Université de

11

Evaporative cooling for Holstein dairy cows under grazing conditions  

NASA Astrophysics Data System (ADS)

. Twenty-four grazing Holstein cows in mid and late lactation were randomly assigned to two treatment groups: control and cooled. The trial was performed at the Experimental Dairy Unit, Rafaela Agricultural Experimental Station (INTA), Argentina. The objective was to evaluate the effects of sprinkler and fan cooling before milkings on milk production and composition. The effects of the cooling system on rectal temperature and respiration rate were also evaluated. Cooled cows showed higher milk production (1.04 l cow-1 day-1). The concentration and yield of milk fat and protein increased in response to cooling treatment. The cooling system also reduced rectal temperature and respiration rate. No effects were observed on body condition. It was concluded that evaporative cooling, which is efficient for housed animals, is also appropriate to improve yields and animal well-being under grazing systems. These results are impressive since the cooling system was utilized only before milkings, in a system where environmental control is very difficult to achieve. This trial was performed during a mild summer. The results would probably be magnified during hotter weather.

Valtorta, Silvia E.; Gallardo, Miriam R.

12

Grazing Systems for Profitable Ranching  

E-print Network

Grazing management is essential to a successful ranching enterprise. Ranchers have several options, including continuous grazing, deferred rotation systems, and short duration grazing. Details about each system are included....

Hanselka, C. Wayne; Ragsdale, Bobby; Rector, Barron S.

2000-05-03

13

Can forage mixtures improve productivity of grazing dairy cows  

Technology Transfer Automated Retrieval System (TEKTRAN)

Maximizing intake of lactating dairy cows is crucial in maintaining high levels of milk production, especially when grazing. Intake can be strongly affected by the amount and type of forage offered to the animals. Pastures containing multiple plant species have been shown to have greater plant pr...

14

Grazing increases the concentration of CLA in dairy cow milka.  

PubMed

An experiment was conducted to examine whether increased CLA in milk of dairy cows fed fresh pasture compared with alfalfa and corn silages was because of ruminal or endogenous synthesis. Eight Holsteins were fed a total mixed ration using alfalfa and corn silages as the forage source in confinement or grazed in a replicated crossover design. The proportion of total fatty acids as CLA (primarily c9, t11-18:2) in g/100 g was 0.44 v. 0.28 in ruminal digesta, 0.89 v. 0.53 in omasal digesta and 0.71 v. 1.06 in milk during confinement feeding and grazing, respectively. Blood plasma CLA was 0.54 v. 1.05 mg/l for the two treatments, respectively. The increased concentration of CLA in milk with grazing likely resulted from increased synthesis through desaturation of t11-18:1 in the mammary gland. PMID:24785122

Lahlou, M N; Kanneganti, R; Massingill, L J; Broderick, G A; Park, Y; Pariza, M W; Ferguson, J D; Wu, Z

2014-04-30

15

A PROFITABILITY ANALYSIS OF DAIRY FEEDING SYSTEMS IN THE NORTHEAST  

Microsoft Academic Search

This study analyzes the use and profitability of three distinct feeding systems; confinement feeding, traditional grazing, and management-intensive grazing from a randomly selected sample of northeastern dairy farms. The confinement feeding farms were significantly larger and produced more milk per cow, while the farms using management-intensive grazing incurred the lowest production costs. Both confinement feeding and management-intensive grazing generated significantly

Jonathan R. Winsten; Robert L. Parsons; Gregory D. Hanson

2000-01-01

16

Greenhouse gas exchange over grazed systems  

NASA Astrophysics Data System (ADS)

Grasslands act as sinks and sources of greenhouse gases (GHG) and are, in conjunction with livestock production systems, responsible for a large share of GHG emissions. Whereas ecosystem scale flux measurements (eddy covariance) are commonly used to investigate CO2 exchange (and is becoming state-of-the-art for other GHGs, too), GHG emissions from agricultural animals are usually investigated on the scale of individual animals. Therefore eddy covariance technique has to be tested for combined systems (i.e. grazed systems). Our project investigates the ability of field scale flux measurements to reliably quantify the contribution of grazing dairy cows to the net exchange of CO2 and CH4. To quantify the contribution of the animals to the net flux the position, movement, and grazing/rumination activity of each cow are recorded. In combination with a detailed footprint analysis of the eddy covariance fluxes, the animal related CO2 and CH4 emissions are derived and compared to standard emission values derived from respiration chambers. The aim of the project is to test the assumption whether field scale CO2 flux measurements adequately include the respiration of grazing cows and to identify potential errors in ecosystem Greenhouse gas budgets.

Felber, R.; Ammann, C.; Neftel, A.

2012-04-01

17

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

18

Practices to Reduce Milk Carbon Footprint on Grazing Dairy Farms in Southern Uruguay: Case Studies.  

Technology Transfer Automated Retrieval System (TEKTRAN)

Carbon footprint (CF) is an increasingly relevant indicator to estimate the impact of a product on climate change. This study followed international guidelines to quantify the CF of milk produced on 24 dairy farms in Uruguay. Cows were grazed all year and supplemented with concentrate feeds. These d...

19

Effects of co-grazing dairy heifers with goats on animal performance, dry matter yield, and pasture forage composition.  

PubMed

Mixed livestock grazing can offer an alternative management system for rearing dairy replacement heifers (Bos taurus). A 2-yr study was conducted during 2009 (yr 1) and 2010 (yr 2) to determine the effects of co-grazing Holstein heifers under rotational stocking with Boer × Kiko goats on animal performance, pasture DM yield, and botanical composition. Each year, 24 heifers (134 ± 6 d of age and 147.4 ± 31.2 kg BW in yr 1; 166 ± 11 d of age and 168.0 ± 27.6 kg BW in yr 2) and 6 goats (2 yr old and 39.7 ± 16.2 kg BW in yr 1; 1 yr old and 33.7 ± 7.4 kg BW in yr 2) were divided into 6 paddocks with 4 heifers and 2 goats, where applicable, per group. Low endophyte-infected tall fescue (Festuca arundinacea Schreb.) and white clover (Trifolium repens L.) pastures were used to evaluate 2 grazing strategies (heifers grazed alone [HO] or heifers co-grazed with goats [HG]). In addition, 6 goats were assigned to 2 paddocks and grazed alone (GO) each year to estimate goat pasture forage intake and compare Haemonchus contortus infection to co-grazed goats. Forage samples were taken monthly to assess DM yield and botanical composition. Samples collected for botanical composition were manually sorted into grass, legume, and weed species. Forage DMI was estimated using a rising plate meter before and after grazing. Heifer BW at the conclusion of yr 1 and yr 2 did not differ between HO and HG (P = 0.40 and P = 0.12, respectively). Likewise, overall ADG did not differ between HO and HG, averaging 0.65 kg/d and 0.63 kg/d over both grazing seasons (P = 0.70). Grazing strategy did not affect forage or total DMI in yr 1; however, HO consumed 2.3 kg/d more forage DM than HG (P < 0.01), resulting in greater total DMI for HO in yr 2 (P < 0.01). Heights at the hip and withers were greater for HO than for HG during both grazing seasons (P < 0.05). Weed presence did not differ between grazing strategies over both grazing seasons as determined by manual harvesting, but visual estimation of botanical composition at the end of yr 2 showed that HO paddocks had 3.5 times more weed presence than HG pastures (P < 0.01). Within the confines of this study, co-grazing did not affect overall heifer BW gain, but it decreased DMI, suggesting that dairy heifers can be co-grazed with goats without negative effects on ADG or feed efficiency. PMID:22952353

Dennis, T S; Unruh-Snyder, L J; Neary, M K; Nennich, T D

2012-12-01

20

Effect of vitamin E on milk composition of grazing dairy cows supplemented with microencapsulated conjugated linoleic acid.  

PubMed

The objective of this study was to evaluate the effect of vitamin E on the fat content and fatty acid profile of grazing dairy cows supplemented with microencapsulated conjugated linoleic acid. Eight New Zealand Holstein cows in a rotational grazing system were used, in a crossover design, randomly assigned to four treatments: control (base diet with microencapsulated conjugated linoleic acid) and three levels of vitamin E (control with 4,000; 8,000; and 12,000 IU/cow per day). All the cows received a supplement apportioning 5 g of cis-9, trans-11, and 5 g of trans-10, cis-12 of conjugated linoleic acid. Moreover, they each received 4-kg dry matter (DM) concentrate and 3.2-kg DM corn silage every day. There were no differences in dry matter intake, milk production, milk composition (fat, protein, and lactose), or fatty acid profile as an effect of vitamin E, and fat content remained under 3 % in all treatments. Therefore, under the conditions that this experiment was carried out, high concentrations of vitamin E in the diet of grazing dairy cows do not inhibit milk fat depression associated with conjugated linoleic acid. It also has no effect on the fatty acid profile of the milk. PMID:23828556

Ramírez-Mella, Monica; Hernández-Mendo, Omar; Ramírez-Bribiesca, Efren Jacinto; Améndola-Massiotti, Ricardo Daniel; Crosby-Galván, María M; Burgueño-Ferreira, Juan A

2013-11-01

21

Grazing behaviour, physical activity and metabolic profile of two Holstein strains in an organic grazing system.  

PubMed

The challenge for sustainable organic dairy farming is identification of cows that are well adapted to forage-based production systems. Therefore, the aim of this study was to compare the grazing behaviour, physical activity and metabolic profile of two different Holstein strains kept in an organic grazing system without concentrate supplementation. Twelve Swiss (HCH ; 566 kg body weight (BW) and 12 New Zealand Holstein-Friesian (HNZ ; 530 kg BW) cows in mid-lactation were kept in a rotational grazing system. After an adaptation period, the milk yield, nutrient intake, physical activity and grazing behaviour were recorded for each cow for 7 days. On three consecutive days, blood was sampled at 07:00, 12:00 and 17:00 h from each cow by jugular vein puncture. Data were analysed using linear mixed models. No differences were found in milk yield, but milk fat (3.69 vs. 4.05%, P = 0.05) and milk protein percentage (2.92 vs. 3.20%, P < 0.01) were lower in HCH than in HNZ cows. Herbage intake did not differ between strains, but organic matter digestibility was greater (P = 0.01) in HCH compared to HNZ cows. The HCH cows spent less (P = 0.04) time ruminating (439 vs. 469 min/day) and had a lower (P = 0.02) number of ruminating boli when compared to the HNZ cows. The time spent eating and physical activity did not differ between strains. Concentrations of IGF-1 and T3 were lower (P ? 0.05) in HCH than HNZ cows. In conclusion, HCH cows were not able to increase dry matter intake in order to express their full genetic potential for milk production when kept in an organic grazing system without concentrate supplementation. On the other hand, HNZ cows seem to compensate for the reduced nutrient availability better than HCH cows but could not use that advantage for increased production efficiency. PMID:24548047

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

2014-12-01

22

Successful organic dairy systems  

Technology Transfer Automated Retrieval System (TEKTRAN)

Demand for organic dairy products has continually increased and at times outpaced supply for a number of years. This has created favorable milk pricing for certified organic dairy farmers, as the stability of organic milk prices has provided organic dairy farmers with a security not found in the con...

23

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

24

Effect of concentrate feed level on methane emissions from grazing dairy cows.  

PubMed

Although the effect of nutrition on enteric methane (CH4) emissions from confined dairy cattle has been extensively examined, less information is available on factors influencing CH4 emissions from grazing dairy cattle. In the present experiment, 40 Holstein-Friesian dairy cows (12 primiparous and 28 multiparous) were used to examine the effect of concentrate feed level (2.0, 4.0, 6.0, and 8.0kg/cow per day; fresh basis) on enteric CH4 emissions from cows grazing perennial ryegrass-based swards (10 cows per treatment). Methane emissions were measured on 4 occasions during the grazing period (one 4-d measurement period and three 5-d measurement periods) using the sulfur hexafluoride technique. Milk yield, liveweight, and milk composition for each cow was recorded daily during each CH4 measurement period, whereas daily herbage dry matter intake (DMI) was estimated for each cow from performance data, using the back-calculation approach. Total DMI, milk yield, and energy-corrected milk (ECM) yield increased with increasing concentrate feed level. Within each of the 4 measurement periods, daily CH4 production (g/d) was unaffected by concentrate level, whereas CH4/DMI decreased with increasing concentrate feed level in period 4, and CH4/ECM yield decreased with increasing concentrate feed level in periods 2 and 4. When emissions data were combined across all 4 measurement periods, concentrate feed level (2.0, 4.0, 6.0, and 8.0kg/d; fresh basis) had no effect on daily CH4 emissions (287, 273, 272, and 277g/d, respectively), whereas CH4/DMI (20.0, 19.3, 17.7, and 18.1g/kg, respectively) and CH4-E/gross energy intake (0.059, 0.057, 0.053, and 0.054, respectively) decreased with increasing concentrate feed levels. A range of prediction equations for CH4 emissions were developed using liveweight, DMI, ECM yield, and energy intake, with the strongest relationship found between ECM yield and CH4/ECM yield (coefficient of determination=0.50). These results demonstrate that offering concentrates to grazing dairy cows increased milk production per cow and decreased CH4 emissions per unit of milk produced. PMID:25173463

Jiao, H P; Dale, A J; Carson, A F; Murray, S; Gordon, A W; Ferris, C P

2014-11-01

25

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

26

N leaching to groundwater from dairy production involving grazing over the winter on a clay-loam soil.  

PubMed

This study investigated concentrations of various N species in shallow groundwater (<2.2m below ground level) and N losses from dairy production involving grazing over the winter period on a clay loam soil with a high natural attenuation capacity in southern Ireland (52°51'N, 08°21'W) over a 2-year period. A dense network of shallow groundwater piezometers was installed to determine groundwater flow direction and N spatial and temporal variation. Estimated vertical travel times through the unsaturated zone (<0.5 yr, time lag) allowed the correlation of management with groundwater N within a short space of time. There was a two way interaction of the system and sampling date (P<0.05) on concentrations of DON, oxidised N and NO(3)(-)-N. In contrast, concentrations of NH(4)(+)-N and NO(2)(-)-N were unaffected by the dairy system. Grazing over the winter had no effect on N losses to groundwater. Mean concentrations of DON, NH(4)(+)-N, NO(2)(-)-N and NO(3)(-)-N were 2.16, 0.35, 0.01 and 0.37 mg L(-1) respectively. Soil attenuation processes such as denitrification and DNRA resulted in increased NH(4)(+)-N levels. For this reason, DON and NH(4)(+)-N represented the highest proportion of N losses from the site. Some of the spatial and temporal variation of N concentrations was explained by correlations with selected chemical and hydro-topographical parameters (NO(3)(-)-N/Cl(-) ratio, distance of the sampling point from the closest receptor, watertable depth, depth of sampling piezometer, DOC concentration). A high explanatory power of NO(3)(-)-N/Cl(-) ratio and the distance of the sampling point from the closest receptor indicated the influence of point sources and groundwater-surface water interactions. PMID:22728303

Necpalova, M; Fenton, O; Casey, I; Humphreys, J

2012-08-15

27

Fall-grown oat to extend the fall grazing season for replacement dairy heifers.  

PubMed

Our objective was to assess the pasture productivity and forage characteristics of 2 fall-grown oat (Avena sativa L.) cultivars, specifically for extending the grazing season and reducing reliance on harvested forages by replacement dairy heifers. A total of 160 gravid Holstein heifers (80 heifers/yr) were stratified by weight, and assigned to 1 of 10 identical research pens (8 heifers/pen). Initial body weights were 480 ± 43.5 kg in 2011 and 509 ± 39.4 kg in 2012. During both years of the trial, four 1.0-ha pasture replicates were seeded in August with Ogle oat (Schumitsch Seed Inc., Antigo, WI), and 4 separate, but similarly configured, pasture replicates were seeded with Forage Plus oat (Kratz Farms, Slinger, WI). Heifer groups were maintained as units, assigned to specific pastures, and then allowed to graze fall-oat pastures for 6h daily before returning to the barn, where they were offered a forage-based basal total mixed ration. Two heifer groups were retained in confinement (without grazing) as controls and offered the identical total mixed ration as pasture groups. During 2011, available forage mass increased with strong linear and quadratic effects for both cultivars, peaking at almost 9 Mg/ha on October 31. In contrast, forage mass was not affected by evaluation date in 2012, remaining ? 2,639 kg/ha across all dates because of droughty climatic conditions. During 2012, Ogle exhibited greater forage mass than Forage Plus across all sampling dates (2,678 vs. 1,856 kg/ha), largely because of its more rapid maturation rate and greater canopy height. Estimates of energy density for oat forage ranged from 59.6 to 69.1% during 2011, and ranged narrowly from 68.4 to 70.4% during 2012. For 2011, responses for both cultivars had strong quadratic character, in which the most energy-dense forages occurred in mid November, largely due to accumulation of water-soluble carbohydrates that reached maximum concentrations of 18.2 and 15.1% for Forage Plus and Ogle, respectively. Across the 2-yr trial, average daily gain for grazing heifer groups tended to be greater than heifers remaining in confinement (0.85 vs. 0.74 kg/d), but both management strategies produced weight gains within reasonable proximity to normal targets for heifers in this weight range. Fall-grown oat should be managed as stockpiled forage for deferred grazing, and good utilization of fall-oat forage can be accomplished by a one-time removal of standing forage, facilitated by a single lead wire advanced daily to prevent waste. PMID:24440262

Coblentz, W K; Brink, G E; Hoffman, P C; Esser, N M; Bertram, M G

2014-03-01

28

PREDICTABILITY OF EFFECTS OF ROTATIONAL GRAZING SYSTEMS ALONG ENVIRONMENTAL GRADIENTS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Rotational grazing systems have been implemented in numerous rangeland ecosystems with the desired objectives of increasing homogeneity of use of vegetation through high stocking densities within small pastures and increasing stocking rate. Vegetation and livestock responses to rotational grazing, w...

29

Seasonal variation in methane emission from dairy cows and breeding ewes grazing ryegrass\\/white clover pasture in New Zealand  

Microsoft Academic Search

Daily methane emission from 12 Romney?cross?bred ewes and 10 lactating Friesian dairy cows, rotationally grazed on perennial ryegrass\\/white clover dominant pastures, was measured during four seasons of a year (September, November, March, and June\\/July). Methane emission was measured from each animal for 5 consecutive days in each measurement period using the sulphur hexafluoride tracer gas technique. The pastures varied significantly

M. J. Ulyatt; K. R. Lassey; I. D. Shelton; C. F. Walker

2002-01-01

30

Prevalence of claw disorders in Dutch dairy cows exposed to several floor systems  

Microsoft Academic Search

Claw health was examined in an observational study on Dutch dairy farms with either a slatted floor (SL), slatted floor with manure scraper (SL-SCR), solid con- crete floor (SCF), a straw yard (SY), or a zero-grazing feeding system (ZG). Hooves of cows' hind legs were examined for the presence and severity of claw disor- ders during hoof trimming events at

J. G. C. J. Somers; K. Frankena; E. N. Noordhuizen-Stassen; J. H. M. Metz

2003-01-01

31

Mineral deficiencies in grazing dairy cattle in Kordofan and Darfur regions in western Sudan.  

PubMed

The seasonal changes in mineral profiles in serum of grazing dairy cattle and the concentrations of nutrients available from forages were determined in western Sudan. Blood samples were collected seasonally from dairy cows, Kenana and Botana breeds, in 6 locations in Kordofan and Darfur. Data were analysed as a split-plot design with repeated measures. The results indicated there were significant seasonal changes in concentrations of P, Cu and K, Ca, Mg, Na, Co, and Zn in blood serum of grazing cows. Concentrations of P, Ca and Na in serum were lowest during the late dry season (4.5 mg/dl, 8.21 mg/dl and 129 mEq/L respectively), while concentrations of Cu, deficient throughout the year, were lowest during the rainy season (0.35 microgram/ml). The interaction of location x season was significant for serum P, Ca, Cu, Mg, Na, Co and K. Kenana cattle had lower Zn in serum (0.96 microgram/ml) than Botana cattle (1.13 microgram/ml). During the dry season, forages had very low CP (3.5 +/- 0.5%), high neutral detergent fibre (NDF) (67.5 +/- 1.8%) and high acid detergent (ADF) (38.5 +/- 1.2%) content. Calcium, P and Na levels in forages were deficient during the dry season (0.38 +/- 0.03%, 0.08 +/- 0.03% and 0.047 +/- 0.01% respectively). Copper also was deficient in forages during the dry season, but adequate during the mid-rainy season (3.0 +/- 2.4 and 26.1 +/- 1.5 mg/kg respectively). In conclusion, the low Cu concentration in sera of cattle indicated a possible nutritional deficiency throughout the year, while P, Ca, and Na were low in sera during the late dry season. Thus, seasonal deficiencies of minerals may affect productivity of cattle in the Kordofan and Darfur regions of Sudan. PMID:9719839

Abdelrahman, M M; Kincaid, R L; Elzubeir, E A

1998-04-01

32

Husbandry Factors and the Resumption of Luteal Activity in Open and Zero-Grazed Dairy Cows in Urban and Peri-Urban Kampala, Uganda  

PubMed Central

Contents The study investigated the influence of selected husbandry factors on interval to resumption of post-partum cyclicity among dairy cows in urban and peri-urban Kampala. A prospective study of 85 day post-partum period of 59 dairy cows in open (n = 38) and zero grazing (n = 21) systems was conducted on 24 farms. Cows of parity 1–6 were recruited starting 15–30 days post-partum. Progesterone (P4) content in milk taken at 10–12 day intervals was analysed using ELISA. The cow P4 profiles were classified into ‘normal’ (< 56 days), ‘delayed’ (> 56 days), ‘ceased’ or ‘prolonged’ (if started < 56 days but with abnormal P4 displays) resumption of luteal activity and tested for association with husbandry and cow factors. Of the 59 cows, luteal activity in 81.4% resumed normally and in 18.6%, delayed. Only 23.7% maintained regular luteal activity, while the others had ceased (10.2%), prolonged (37.3%) or unclear luteal activity (20.3%). There were no differences between open and zero-grazed cows. Milk production was higher (p < 0.05) in zero than open grazing, in urban than peri-urban and in cows fed on brew waste (p < 0.001) compared with mill products and banana peels. Results suggest that luteal activity resumes normally in a majority of cows, although only a minority experienced continued normal cyclicity once ovulation had occurred, in the two farming systems irrespective of feed supplements or water, and that supplementing with brew waste is beneficial for milk production. PMID:24930481

Kanyima, BM; Båge, R; Owiny, DO; Ntallaris, T; Lindahl, J; Magnusson, U; Nassuna-Musoke, MG

2014-01-01

33

Premilking teat disinfection: is it worthwhile in pasture-grazed dairy herds?  

PubMed

A controlled trial was conducted in 5 pasture-grazed commercial dairy herds in Australia in 2012 to determine whether premilking teat disinfection and drying of teats reduces clinical mastitis incidence during early lactation by at least 50%. A 50% reduction was estimated to be the minimum required to justify additional costs of labor, disinfectants, and other resources if premilking teat disinfection was implemented in a 500-cow herd averaging 8 clinical cases per 100 cow-months. A secondary aim was to determine whether this premilking teat disinfection routine reduces incidence of new udder infections. Treatment was applied in each herd for approximately 60 d (range of 59.5 to 61 d), commencing in each herd soon after the start of the herd's main or only calving period. Within each herd, cows were allocated to either the treatment (premilking disinfection) or the control (no premilking disinfection) group based on their herd identity number. During the trial period, any cow having a new case of clinical mastitis or an individual cow cell count greater than 250,000 cells/mL of milk (when preceded by individual cow cell counts of 250,000 cells/mL of milk or below) was deemed to have had a new infection. Overall, neither clinical mastitis incidence nor new infection rate differed significantly between treatment and control groups. Over the whole study period, 98 of the 1,029 cows in the premilking disinfection group and 97 of the 1,025 cows in the control group had clinical mastitis. Total cow-days at risk of clinical mastitis were similar in each group. However, clinical incidence rates were markedly lower in treatment cows in one herd (herd 3; incidence rate ratio=0.34) and there was some evidence that new infection incidence rates were lower in treated cows in this herd (incidence rate ratio=0.42). Rainfall during the study period was below long-term district average in all 5 study herds. Cows' teats were less dirty than in previous, wetter years for the 4 herds where no significant clinical mastitis response was detected but some teat soiling was observed in herd 3 during the study period. Routine application of premilking teat disinfection in pasture-grazed herds is unlikely to produce a worthwhile (economic) reduction in the number of clinical mastitis cases when teats are relatively clean and dry and the clinical mastitis incidence is low. However, premilking disinfection might be worthwhile during periods when teats are heavily soiled and the incidence of clinical mastitis due to environmental pathogens is high. PMID:25282424

Morton, John M; Penry, John F; Malmo, Jakob; Mein, Graeme A

2014-12-01

34

Grazing: the whole picture  

Technology Transfer Automated Retrieval System (TEKTRAN)

Environmental concerns for our farms include nutrient leaching to ground water, runoff in surface water, gaseous emissions, and the carbon footprint of our production systems. Recent reports have labeled grazing-based dairies as less environmentally sustainable compared to year around confinement sy...

35

Short communication: Effects of dietary nonstructural carbohydrates pre- and postpartum on reproduction of grazing dairy cows.  

PubMed

The working hypothesis was that postpartum anovulatory intervals (PPAI) of grazing dairy cows are shortened by inclusion of concentrates that increase the nonstructural carbohydrate content of the transition diet. Dietary treatments were arranged as a 2x2 factorial, with 68 multiparous cows assigned to isoenergetic diets (114 MJ of metabolizable energy/cow per day) of pasture and pasture silage (PreP) or pasture and pasture silage supplemented with 3 kg of dry matter/cow per day a corn- and barley-based concentrate for 36 d prepartum (PreC). After calving, cows within each prepartum diet group were managed on isoenergetic diets (179 MJ of metabolizable energy/cow per day) of either pasture and pasture silage (PostP) or pasture and pasture silage supplemented with 5 kg of dry matter/cow per day a corn- and barley-based concentrate (PostC) for at least 35 d and until reestablishment of ovulatory cycles. Relative to day of calving (d 0), blood samples were collected at least weekly from d -28 to 35 and milk samples were collected twice weekly for progesterone determination to diagnose ovulatory status. The main variable of interest was PPAI, defined as the interval between calving and the first detected increase in milk progesterone (>3 ng/mL), followed by a pattern of progesterone concentrations consistent with onset of an ovulatory cycle. Subsequent mating records, pregnancy testing, and recalving data were also examined. Prepartum diet did not affect reproduction. The PPAI was 8 d shorter and the 6-wk pregnancy rate was 17% greater in PostC cows compared with PostP cows. Measured indicators of metabolic state and energy balance were poorly related to PPAI. The results support the existence of nutritional signals associated with nonstructural carbohydrates in the postpartum diet, independent of energy balance; these signals benefit the physiological mechanisms underlying the timing of first ovulation and possibly subsequent breeding performance. PMID:20723702

Burke, C R; Kay, J K; Phyn, C V C; Meier, S; Lee, J M; Roche, J R

2010-09-01

36

Effect of total mixed ration composition and daily grazing pattern on milk production, composition and fatty acids profile of dairy cows.  

PubMed

The possibilities of using high quality pastures in conjunction with total mixed ration (TMR) during the grazing season have been examined. An experiment with sixteen Holstein cows blocked and randomly assigned to four treatments in a factorial arrangement was conducted in order to evaluate the influence of grazing time of day (day or night) and type of silage (maize or Italian ryegrass) included in the TMR of dairy cows grazing 12 h daily on milk yield, composition and fatty acid profile. The silage type had no effect on the dry matter intake, milk yield and fat and protein proportions. However, cows grazing during the night ate more grass than cows grazing during the day (8·53 vs. 5·65 kg DM/d; P<0·05). No differences were seen between grazing-time with respect to milk production, fat and protein contents. However, the proportion of polyunsaturated fatty acid was higher in milk of dairy cows grazing at night-time than grazing at day-time, especially 18:2n-6 (2·37 vs. 2·12 g/100 g FA respectively, P<0·05) and 18:2cis9trans11 (2·08 vs. 1·74 g/100 g FA respectively, P<0·05). PMID:25263635

Hernández-Ortega, Martha; Martínez-Fernández, Adela; Soldado, Ana; González, Amelia; Arriaga-Jordán, Carlos M; Argamentería, Alejandro; de la Roza-Delgado, Begoña; Vicente, Fernando

2014-11-01

37

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. PMID:23213627

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

2012-01-01

38

Effects of dietary conjugated linoleic acid on production and metabolic parameters in transition dairy cows grazing fresh pasture.  

PubMed

Supplementation with a high dose (600 g/d) of rumen inert conjugated linoleic acids (RI-CLA) inhibits milk fat synthesis in total mixed ration (TMR)-fed dairy cows immediately post partum. However, effects of RI-CLA on milk fat and bioenergetic parameters during the transition period in grazing cows have not been investigated. Multiparous Holstein cows (n=39) grazing pasture were randomly assigned to one of three treatments: (1) pasture (PAS), (2) PAS+540 g/d Hyprofat (palm oil; HYPRO) and (3) PAS+600 g/d RI-CLA. HYPRO and RI-CLA supplements were isoenergetic, fed twice daily at 7.00 and 16.00 and provided 0 and 125 g CLA/d, respectively. Treatments began 27+/-10 d prepartum and continued until 36+/-1 days in milk (DIM). There was little or no overall effect of RI-CLA on content or yield of milk protein and lactose. RI-CLA supplementation decreased overall milk fat content and yield with RI-CLA-induced milk fat depression (MFD) becoming significant by day 3 when compared with PAS and by day 6 when compared with HYPRO. MFD continued to increase in severity during the first 24 d post partum after which MFD reached a plateau (approximately 40%; RI-CLA v. HYPRO). Pasture-fed cows produced less milk (19.4 kg/d) than the lipid-supplemented groups and although there were no overall differences in milk yield between RI-CLA and HYPRO (22.3 kg/d) a curvilinear relationship (R2=0.57) existed between the RI-CLA-induced milk yield response and extent of MFD. RI-CLA tended to increase milk yield (1.8 kg/d) compared with HYPRO until MFD exceeded 35% (approximately day 21), after which point the positive milk yield response was eliminated. Milk fat trans-10, cis-12 CLA content averaged 0.25 g/100 g in the RI-CLA treatment, was temporally independent, and was undetectable in PAS and HYPRO treatments. Based on the milk fat 14ratio1/14ratio0 ratio, RI-CLA decreased the overall Delta9-desaturase system compared with PAS and HYPRO. Compared with HYPRO, RI-CLA had no effect on plasma glucose, insulin, leptin, or NEFA concentrations. Results indicate that a high RI-CLA dose decreases milk fat synthesis and tends to increase milk yield immediately post partum in pasture-fed cows; however, excessive MFD (>35%) appears to be associated with a diminished milk yield response. PMID:16836800

Kay, Jane K; Roche, John R; Moore, Chel E; Baumgard, Lance H

2006-08-01

39

Livestock and vegetation responses to stocking rate and grazing system  

Technology Transfer Automated Retrieval System (TEKTRAN)

Vegetation and livestock responses from a 25 year (1982-2006) grazing system and stocking rate study in the northern mixed-grass prairie at the USDA-Agricultural Research Service, High Plains Grasslands Research Station near Cheyenne, Wyoming are presented here. Long-term grazing treatments of stock...

40

Effects of strain of Holstein-Friesian and concentrate supplementation on the fatty acid composition of milk fat of dairy cows grazing pasture in early lactation  

Microsoft Academic Search

The effect of a grain-based concentrate supplement on fatty acid (FA) intake and concentration of milk FA in early lactation was investigated in grazing dairy cows that differed in their country of origin and in their estimated breeding value for milk yield. It was hypoth- esized that Holstein-Friesian cows of North American (NA) origin would produce milk lower in milk

W. J. Wales; E. S. Kolver; A. R. Egan; R. Roche

2009-01-01

41

Adaptation and evaluation of the GrazeIn model of grass dry matter intake and milk yield prediction for grazing dairy cows.  

PubMed

The prediction of grass dry matter intake (GDMI) and milk yield (MY) are important to aid sward and grazing management decision making. Previous evaluations of the GrazeIn model identified weaknesses in the prediction of GDMI and MY for grazing dairy cows. To increase the accuracy of GDMI and MY prediction, GrazeIn was adapted, and then re-evaluated, using a data set of 3960 individual cow measurements. The adaptation process was completed in four additive steps with different components of the model reparameterised or altered. These components were: (1) intake capacity (IC) that was increased by 5% to reduce a general GDMI underprediction. This resulted in a correction of the GDMI mean and a lower relative prediction error (RPE) for the total data set, and at all stages of lactation, compared with the original model; (2) body fat reserve (BFR) deposition from 84 days in milk to next calving that was included in the model. This partitioned some energy to BFR deposition after body condition score nadir had been reached. This reduced total energy available for milk production, reducing the overprediction of MY and reducing RPE for MY in mid and late lactation, compared with the previous step. There was no effect on predicted GDMI; (3) The potential milk curve was reparameterised by optimising the rate of decrease in the theoretical hormone related to secretory cell differentiation and the basal rate of secretory cell death to achieve the lowest possible mean prediction error (MPE) for MY. This resulted in a reduction in the RPE for MY and an increase in the RPE for GDMI in all stages of lactation compared with the previous step; and (4) finally, IC was optimised, for GDMI, to achieve the lowest possible MPE. This resulted in an IC correction coefficient of 1.11. This increased the RPE for MY but decreased the RPE for GDMI compared with the previous step. Compared with the original model, modifying this combination of four model components improved the prediction accuracy of MY, particularly in late lactation with a decrease in RPE from 27.8% in the original model to 22.1% in the adapted model. However, testing of the adapted model using an independent data set would be beneficial and necessary to make definitive conclusions on improved predictions. PMID:24438821

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

2014-04-01

42

MOLASSES AS THE PRIMARY ENERGY SUPPLEMENT ON AN ORGANIC GRAZING DAIRY FARM  

Technology Transfer Automated Retrieval System (TEKTRAN)

Organic dairies in New York face challenges, including the high cost of purchasing organic feed grains. Many of these farms are looking for alternative ingredients to use that can be reasonably fed to lactating dairy cows, and that are less costly. Molasses seems to be a viable, less expensive, so...

43

Cash Wheat in a Wheat-Ryegrass Grazing System.  

E-print Network

~-~ash Wheat ? Ina B~1452 November 1983 t Wheat--Ryegrass Grazing System ~ THE TEXAS AGRICULTURAL EXPERIMENT STATION / Neville P. Clarke, Director / The Texas A&M University System / College Station, 'l"exas SUMMARY Wheat is an important...

Nelson, L.R.; Rouquette, F.M. Jr.; Randel, R.D.

1983-01-01

44

Effect of supplementation of grazing dairy ewes with a cereal concentrate on animal performance and milk fatty acid profile.  

PubMed

This work was conducted to investigate the effect of supplementing grazing ewes on pasture with a cereal concentrate on the milk fatty acid (FA) profile. Ninety Assaf ewes in mid lactation were distributed in 9 lots of 10 animals each and allocated to 3 feeding regimens: 1) pasture--ewes were only allowed to graze pasture (an irrigated sward of Lolium perenne, Trifolium pratense, and Dactylis glomerata); 2) PS--grazing ewes were supplemented with oat grain (700 g/animal and day); and 3) TMR--ewes were fed ad libitum a total mixed ration (TMR; 80:20 concentrate/forage ratio). Milk yield and composition were recorded for 5 wk. The highest milk yield was observed in ewes receiving the TMR and the lowest in grazing ewes supplemented with oat grain. Productions of milk fat, protein, and total solids showed the lowest values in treatment PS. The atherogenicity index, which comprises C12:0, C14:0, and C16:0, in PS milk fat was no different from that observed in milk from animals on pasture (1.53 for pasture, 1.54 for PS, and 3.22 for TMR). Oat grain supplementation generated higher amounts of C18:0 and cis-9 C18:1 in milk fat than the pasture-only diet, but significantly decreased the levels of alpha-linolenic acid and most of intermediates of the process of biohydrogenation of this FA. Cis-9 trans-11 C18:2 and trans-11 C18:1, its precursor for endogenous synthesis in the mammary gland, were lower in PS (0.58 and 1.59 g/100 g of total FA) than in TMR (0.72 and 1.92 g/100 g of total FA) and very different from the results observed in grazing ewes receiving no supplement (1.21 and 3.88 g/100 g of total FA). Furthermore, the lowest levels of trans-10 C18:1 and trans-10 cis-12 C18:2 were detected in the milk fat of ewes fed pasture. It is concluded that, when pasture quality and availability do not limit dairy production, supplementation of grazing ewes with oat grain compromised the milk FA profile without any significant positive effect on milk production. PMID:19620680

Gómez-Cortés, P; Frutos, P; Mantecón, A R; Juárez, M; de la Fuente, M A; Hervás, G

2009-08-01

45

Knowledge and tools to enhance resilience of beef grazing systems for sustainable animal protein production.  

PubMed

Ruminant livestock provides meat and dairy products that sustain health and livelihood for much of the world's population. Grazing lands that support ruminant livestock provide numerous ecosystem services, including provision of food, water, and genetic resources; climate and water regulation; support of soil formation; nutrient cycling; and cultural services. In the U.S. southern Great Plains, beef production on pastures, rangelands, and hay is a major economic activity. The region's climate is characterized by extremes of heat and cold and extremes of drought and flooding. Grazing lands occupy a large portion of the region's land, significantly affecting carbon, nitrogen, and water budgets. To understand vulnerabilities and enhance resilience of beef production, a multi-institutional Coordinated Agricultural Project (CAP), the "grazing CAP," was established. Integrative research and extension spanning biophysical, socioeconomic, and agricultural disciplines address management effects on productivity and environmental footprints of production systems. Knowledge and tools being developed will allow farmers and ranchers to evaluate risks and increase resilience to dynamic conditions. The knowledge and tools developed will also have relevance to grazing lands in semiarid and subhumid regions of the world. PMID:25376887

Steiner, Jean L; Engle, David M; Xiao, Xiangming; Saleh, Ali; Tomlinson, Peter; Rice, Charles W; Cole, N Andy; Coleman, Samuel W; Osei, Edward; Basara, Jeffrey; Middendorf, Gerad; Gowda, Prasanna; Todd, Richard; Moffet, Corey; Anandhi, Aavudai; Starks, Patrick J; Ocshner, Tyson; Reuter, Ryan; Devlin, Daniel

2014-11-01

46

Grazing dairy cows had decreased interferon-?, tumor necrosis factor, and interleukin-17, and increased expression of interleukin-10 during the first week after calving.  

PubMed

Peripartum, and especially during the transition period, dairy cows undergo dramatic physiological changes. These coincide with an increased risk of disease during the first 2 wk after calving and have been linked to dairy cows failing to achieve production as well as reproductive targets. Previous evidence suggests that these physiological changes affect the immune system and that transition dairy cows experience some form of reduced immunocompetence. However, almost all of these studies were undertaken in high-production, housed dairy cows. Grazing cows have much lower levels of production and this study aimed to provide clarity whether or not the dysfunctional attributes of the peripartum immune system reported in high production housed cows are evident in these animals. Therefore, cell culture techniques, flow cytometry, and quantitative PCR were applied to analyze the cellular composition of peripheral blood mononuclear cells from transition dairy cows as well as the performance of these cells in an in vitro assay. First, a combination of in vitro stimulation and quantitative PCR for cytokines was validated as a quantifiable immunocompetence assay in 29 cattle and a correlation of quantitative PCR and ELISA demonstrated. Second, the relative number of T helper cells, cytotoxic T cells, B cells, ?? T cells, natural killer cells, and monocytes in peripheral blood was measured, of which B cells and natural killer cells increased in number postcalving (n=29) compared with precalving. Third, following in vitro stimulation cytokine profiles indicated decreased expression of IFN?, tumor necrosis factor, and IL-17 and increased expression of IL-10 wk 1 after calving, which later all returned to precalving values (n=39). Additionally, treatment of transition cows with a nonsteroidal anti-inflammatory drug (i.e., carprofen) administered on d 1, 3, and 5 postcalving (n=19; untreated control n=20) did not affect the cytokine expression at any time point. In conclusion, an immunocompetence assay has been developed that highlights a characteristic expression pattern for IFN?, tumor necrosis factor, IL-17, and IL-10 that reflects a state of reduced immunocompetence in moderate-yielding pasture-based transition cows after calving, which is similar to that described for higher-yielding housed cows. PMID:25483203

Heiser, Axel; McCarthy, Allison; Wedlock, Neil; Meier, Susanne; Kay, Jane; Walker, Caroline; Crookenden, Mallory A; Mitchell, Murray D; Morgan, Stuart; Watkins, Kate; Loor, Juan J; Roche, John R

2015-02-01

47

Comparative Utilization of Alfalfa-Bromegrass Pasture Under Rotational and Daily Strip Grazing1  

Microsoft Academic Search

SUMMARY The efficiency of herbage utilization from alfalfa-bromegrass (M. falcata and B. inermis) pasture under rotational and strip-grazing management was compared for three grazing seasons. The expression of increased efficiency as increased carrying capacity was precluded by restricting grazing, so that the cows on each system had equal opportunity to utilize the available herbage. Under these restrictions, dairy cows at

A. L. Brundage; W. J. Sweetman

1958-01-01

48

A comparison of frontal and continuous systems of grazing  

E-print Network

Systems of Grazing. (May 1991) Fabian de Achaval O'Farrell, Ingeniero en Produccion Agropecuhria, Universidad Catolica Argentina; Chair of Advisory Committee: Dr. W. C. Ellis The objectives of this research were to: 1) compare ADG and gain...

Achaval O'Farrell, Fabian de

1991-01-01

49

Plant Diversity: Effects of Grazing System and Stocking Rate in Northern Mixed-Grass Prairie  

Technology Transfer Automated Retrieval System (TEKTRAN)

Effects of grazing system, stocking rate, and grazing system X stocking rate interactions, on plant diversity are poorly understood in rangelands. A grazing system (season-long and short-duration rotational grazing) X stocking rate (light: 16 steers•80 ha-1, moderate: 4 steers•12 ha-1 and heavy: 4 s...

50

Assessment of Prior Grazing Experiences on Adaption to Pasture and Performance of Dairy Heifers.  

Technology Transfer Automated Retrieval System (TEKTRAN)

The objective of this study was to evaluate how previous grazing experience affects animal behavior on pasture. Animal behavior was monitored in 32 Holstein (n = 21) and Holstein-Jersey (n = 11) yearlings. Two heifer groups (n = 8 per group) had been exposed to pasture from August through October 20...

51

Case study: molasses as the primary energy source on an organic grazing dairy  

Technology Transfer Automated Retrieval System (TEKTRAN)

Organic dairies face many challenges, one of which is the high cost of purchased organic grains. Molasses may be a less expensive energy alternative. However, anecdotal results have been mixed for farms that used molasses as the sole energy source. This research project quantified animal performance...

52

Modelling nitrous oxide emissions from grazed grassland systems.  

PubMed

Grazed grassland systems are an important component of the global carbon cycle and also influence global climate change through their emissions of nitrous oxide and methane. However, there are huge uncertainties and challenges in the development and parameterisation of process-based models for grazed grassland systems because of the wide diversity of vegetation and impacts of grazing animals. A process-based biogeochemistry model, DeNitrification-DeComposition (DNDC), has been modified to describe N(2)O emissions for the UK from regional conditions. This paper reports a new development of UK-DNDC in which the animal grazing practices were modified to track their contributions to the soil nitrogen (N) biogeochemistry. The new version of UK-DNDC was tested against datasets of N(2)O fluxes measured at three contrasting field sites. The results showed that the responses of the model to changes in grazing parameters were generally in agreement with observations, showing that N(2)O emissions increased as the grazing intensity increased. PMID:22243868

Wang, Junye; Cardenas, Laura M; Misselbrook, Tom H; Cuttle, Steve; Thorman, Rachel E; Li, Changsheng

2012-03-01

53

Effects of supplementing complexed zinc, manganese, copper and cobalt on lactation and reproductive performance of intensively grazed lactating dairy cattle on the South Island of New Zealand  

Microsoft Academic Search

Five hundred and fifty-five healthy, pregnant, non-lactating Holstein–Friesian cows on an intensively grazed, commercial dairy were assigned to a study to determine effects of daily water treatment with Co glucoheptonate and amino acid complexes of Zn, Mn and Cu on lactational performance, fertility and claw hardness. Cows were randomly assigned to treatment based upon eartag number. At approximately 35 days

L. M. Griffiths; S. H. Loeffler; M. T. Socha; D. J. Tomlinson; A. B. Johnson

2007-01-01

54

Experimental Evidence for Grazing System Research: What Does it Tell Us?  

Technology Transfer Automated Retrieval System (TEKTRAN)

Research on grazing systems has been conducted for the past 60 years and the experimental evidence consistently indicates that rotational grazing is comparable to continuous grazing on rangelands. For example, over 80% of the peer-reviewed studies reported that rotational grazing did not result in h...

55

Carbon footprint of dairy production systems  

Technology Transfer Automated Retrieval System (TEKTRAN)

Greenhouse gas (GHG) emissions and their potential impact on global warming has become an important national and international concern. Dairy production systems along with all other types of animal agriculture are recognized as a source of GHG. Although little information exists on the net GHG emiss...

56

100% PASTURE FOR DAIRY COWS: PROFITABILITY, MILK QUALITY AND ANIMAL WELFARE  

Technology Transfer Automated Retrieval System (TEKTRAN)

Some dairy farmers and consumers are proponents of a diet for dairy cows with 100% pasture and no supplementation, similar to a New Zealand system. However, for US dairy producers who are thinking about a “100% pasture” system, this may not be a reality. Even during the 6 to 7 months grazing period,...

57

Effect of grazing system on fetal development in Nellore cattle.  

PubMed

Intensive grazing systems for beef females, based on abundant availability of high quality forages and supplementary concentrates, may affect fetal development. The objective of this study was to determine the effect of grazing system on length of gestation, fetal development, and characteristics of the calf at birth. Twenty-four pregnant (bred to Nellore bulls) Nellore females were allocated into two groups. The control group (G1) grazed Brachiaria decumbens (signal grass) in a traditional (extensive) grazing system and the second group (G2) were managed on Panicum maximumcv. Tanzania 1 (Tanzania grass) in an intensive grazing system. Fetal development was evaluated by ultrasonography on days 31, 45, 59, 94, 122, 220, and 255 of gestation. The diameter of the amniotic and allantoic cavities, crown-rump length, circumference, and diameter of the head and ocular orbit were determined. At birth, calves were weighed and height, length, thoracic circumference, and ocular orbit and bi-parietal diameters were measured. There were no differences (P > 0.05) in fetal development. The G1 cows had a longer gestation period (4.5 days; P<0.05) and their calves had greater (P<0.05) weight, height, length, and thoracic circumference at birth. In conclusion, Nellore females raised under intensive pasture management conditions, had significantly shorter gestation and smaller calves at birth than those raised under extensive pasture management conditions. Therefore, adoption of new management practices (e.g. intensive pasture management), should take into consideration animal behavior and productivity. PMID:15036958

Bergamaschi, M A C M; Vicente, W R R; Barbosa, R T; Marques, J A; Freitas, A R

2004-05-01

58

Invited review: Genetic considerations for various pasture-based dairy systems.  

PubMed

Pasture-based dairy systems use grazing to supply significant percentages of the dry matter intake of cows and heifers. Such systems vary from those for which pasture is used only as a supplemental feed for cows primarily fed a total mixed ration to those for which pasture is the primary source of dry matter for the herd. Cows that are optimal in a pasture system share many general characteristics with cows that are appropriate for a nonpasture system, including feed efficiency, maintenance of body condition, reproductive fitness, udder health, longevity, and the ability to adapt to various management systems. However, in such divergent feeding systems, the relative importance of various traits can differ. In pasture systems where cow nutrient demand intentionally coincides with seasonal forage availability, the focus of selection has emphasized fertility and other fitness traits, as well as yields of milk or milk components. Breeds or strains with higher yields of protein and fat typically have advantages in grazing systems that supply milk to solids-based or cheese markets. Holstein cows with high percentages of North American ancestry can work well in grazing systems that include supplemental concentrates or partial mixed rations, particularly if calving intervals are less restrictive. Crossbred cows can be selected for use in specific grazing systems as well as for specific milk markets, with the added advantage of heterosis. Breeds and crosses with high fertility are important for seasonal breeding and calving. The ability of cattle to both milk and maintain sufficient body condition for reproduction is important for any dairy production system but is critical in a seasonal system. Dairy farms that depend on pasture for most of dry matter for cows typically have lower production per cow than nongrazing dairies but have the potential to be economically competitive because of lower operating and overhead costs. Although the principles of selection are similar across a variety of pasture-based and nonpasture systems, we document from studies and observations covered herein that optimal breeds, breed strains, and selection strategies can differ based on varying management constraints and objectives. PMID:25151878

Washburn, S P; Mullen, K A E

2014-10-01

59

Components of dairy manure management systems.  

PubMed

Dairy manure management systems should account for the fate of excreted nutrients that may be of environmental concern. Currently, regulatory oversight is directed primarily at the assurance of water quality; N is the most monitored element. Land application of manure at acceptable fertilizer levels to crops produced on the farm by hauling or by pumping flushed manure effluent through irrigation systems is the basis of most systems. Nutrient losses to surface and groundwaters can be avoided, and significant economic value can be obtained from manure as fertilizer if adequate crop production is possible. Dairies with insufficient crop production potential need affordable systems to concentrate manure nutrients, thereby reducing hauling costs and possibly producing a salable product. Precipitation of additional nutrients from flushed manures with sedimented solids may be possible. Composting of separated manure solids offers a possible method to stabilize solids for distribution, but, most often, solids separated from dairy manures are fibrous and low in fertility. Manure solids combined with wastes from other sources may have potential if a marketable product can be produced or if sufficient subsidy is received for processing supplementary wastes. Solutions to odor problems are needed. Energy generated from manure organic matter, via anaerobic digestion, reduces atmospheric emissions of methane and odorous compounds. Use of constructed wetlands or harvesting of photosynthetic biomass from wastewater has the potential to improve water quality, making extensive recycling possible. PMID:7929962

Van Horn, H H; Wilkie, A C; Powers, W J; Nordstedt, R A

1994-07-01

60

Frequent moving of grazing dairy cows to new paddocks increases the variability of milk fatty acid composition.  

PubMed

The aim of this work was to investigate the variations of milk fatty acid (FA) composition because of changing paddocks in two different rotational grazing systems. A total of nine Holstein and nine Montbéliarde cows were divided into two equivalent groups according to milk yield, fat and protein contents and calving date, and were allocated to the following two grazing systems: a long duration (LD; 17 days) of paddock utilisation on a heterogeneous pasture and a medium duration (MD) of paddock utilisation (7 to 10 days) on a more intensively managed pasture. The MD cows were supplemented with 4 kg of concentrate/cow per day. Grazing selection was characterised through direct observations and simulated bites, collected at the beginning and at the end of the utilisation of two subsequent MD paddocks, and at the same dates for the LD system. Individual milks were sampled the first 3 days and the last 2 days of grazing on each MD paddock, and simultaneously also for the LD system. Changes in milk FA composition at the beginning of each paddock utilisation were highly affected by the herbage characteristics. Abrupt changes in MD milk FA composition were observed 1 day after the cows were moved to a new paddock. The MD cows grazed by layers from the bottom layers of the previous paddock to the top layers of the subsequent new paddock, resulting in bites with high organic matter digestibility (OMD) value and CP content and a low fibre content at the beginning of each paddock utilisation. These changes could induce significant day-to-day variations of the milk FA composition. The milk fat proportions of 16:0, saturated FA and branched-chain FA decreased, whereas proportions of de novo-synthesised FA, 18:0, c9-18:1 and 18:2n-6 increased at paddock change. During LD plot utilisation, the heterogeneity of the vegetation allowed the cows to select vegetative patches with higher proportion of leaves, CP content, OMD value and the lowest fibre content. These small changes in CP, NDF and ADF contents of LD herbage and in OMD values, from the beginning to the end of the experiment, could minimally modify the ruminal ecosystem, production of precursors of de novo-synthesised FA and ruminal biohydrogenation, and could induce only small day-to-day variations in the milk FA composition. PMID:25483022

Coppa, M; Farruggia, A; Ravaglia, P; Pomiès, D; Borreani, G; Le Morvan, A; Ferlay, A

2014-12-01

61

Using post-grazing sward height to impose dietary restrictions of varying duration in early lactation: its effects on spring-calving dairy cow production.  

PubMed

The objective of this study was to investigate the immediate and carryover effects of imposing two post-grazing sward heights (PGSH) for varying duration during early lactation on sward characteristics and dairy cow production. The experiment was a randomised block design with a 2×2 factorial arrangement of treatments. A total of 80 spring-calving (mean calving date - 6 February) dairy cows were randomly assigned, pre-calving, to one of the two (n=40) PGSH treatments - S (2.7 cm) and M (3.5 cm) - from 13 February to 18 March, 2012 (P1). For the subsequent 5-week period (P2: 19 March to 22 April, 2012), half the animals from each P1 treatment remained on their treatment, whereas the other half of the animals switched to the opposing treatment. Following P2, all cows were managed similarly for the remainder of the lactation (P3: 23 April to 4 November, 2012) to measure the carryover effect. Milk production, BW and body condition score were measured weekly, and grass dry matter intake (GDMI) was measured on four occasions - approximately weeks 5, 10, 15 and 20 of lactation. Sward utilisation (above 2.7 cm; P1 and P2) was significantly improved by reducing the PGSH from 3.5 (0.83) to 2.7 cm (0.96). There was no effect of PGSH on cumulative annual grass dry matter (DM) production (15.3 t DM/ha). Grazing to 2.7 cm reduced GDMI by 1.7 and 0.8 kg DM/cow in P1 and P2, respectively, when compared with 3.5 cm (13.3 and 14.0 kg/cow per day, respectively). Cows grazing to 2.7 cm for both P1 and P2 (SS) tended to have reduced cumulative 10-week milk yield (-105 kg) and milk solids yield (-9 kg) when compared with cows grazing to 3.5 cm for both periods (MM; 1608 and 128 kg/cow, respectively). Treatments that alternated PGSH at the end of P1, SM and MS had intermediate results. There was no interaction between P1 and P2 treatments. There was also no carryover effect of early lactation grazing regime on milk and milk solids production in P3, given the reduction in early lactation milk yield. The results indicate that the diet of dairy cows should not be restricted by imposing a severe PGSH for all of the first 10 weeks of lactation, cows should graze to 3.5 cm for at least 5 of these weeks. PMID:25471149

Crosse, M; O'Donovan, M; Boland, T M; Delaby, L; Ganche, E; Kennedy, E

2014-12-01

62

Trace gas emissions following deposition of excreta by grazing dairy cows in eastern Canada  

NASA Astrophysics Data System (ADS)

The N2O emission factor proposed for cattle excreta N by the Tier I IPCC methodology (EF3) is 2% (IPCC, 2006). While N2O emissions from excreta deposited by grazing animals have been reported in several publications, relatively few estimated EF3 values because measurements did not cover the entire year. This study measured N2O and CH4 flux and crop dry matter (DM) yield over two years (2009 to 2011) from a clay and a sandy loam soil cultivated with Timothy grass (Phleum pratense L.). A split-plot design was used on each soil type, with different application dates (either spring, summer or autumn application) as main plots and treatment (U-50: urine 50 g N m-2, U-100: urine 100 g N m-2, dung: 60 g N m-2, and control) as the sub-plots. Regardless of application time, annual DM yield increased in all treated plots when compared to the control. Also, DM yields were generally greater when urine as opposed to dung was applied suggesting greater N-availability from the urine application. The CH4 flux from the dung plots increased for only the first two weeks after treatment while the flux from the urine plots was similar to the control plots. Cumulative N2O emissions on the U-50 and U-100 plots increased linearly with urine N rate on both soils, resulting in nearly identical mean emission factors for both urine rates. The emission factor for the urine was three times greater on the clay (1.02% of applied N on both rates) than on the sandy loam soil (0.26% (U100) and 0.31% (U50) of applied N). Cumulative N2O emissions from dung plots also differed between soil types; however the impact of soil type on N2O emissions was opposite to that of urine, with greater losses from the sandy loam (0.15%) compared with the clay soil (0.07%). These results suggest that estimates of soil N2O emissions by grazing cattle in Eastern Canada obtained using the IPCC default methodology are overestimates of actual values and that these estimates for should include a stratification according to soil type.

Rochette, P.; Pelster, D. E.; Chantigny, M. H.; Angers, D. A.; Liang, C.; Belanger, G.; Ziadi, N.; Charbonneau, E.; Pellerin, D.

2012-04-01

63

Effects of stocking density and concentrate supplementation of grazing dairy cows on milk production, composition and processing characteristics.  

PubMed

The effects on milk composition and processing characteristics of varying grass supply by changing stocking density and of offering a concentrate supplement were investigated. The experiment was conducted over 28 weeks of the lactation (April-October) using 48 spring-calved Friesian-Holstein cows. Three herds each of 16 cows were offered a restricted grass supply, a standard grass supply and a standard grass supply with a supplement of 3 kg concentrate/d. Treatment groups were grazed separately with a residence time of 3 d/paddock. Milk production, composition and processing characteristics such as renneting properties, ethanol stability and plasmin activity were measured weekly. Increasing stocking density above the standard system resulted in significant reductions in milk fat and protein yields, the concentrations of total protein, casein and whey proteins, and a deterioration in most processing characteristics. Imposing concentrate supplementation on the standard system increased total protein, casein and whey protein concentrations but generally did not improve processing characteristics except for ethanol stability. These results suggest that the standard grass supply in a rotational grazing paddock system can support efficient production of quality milk, and concentrate supplementation will not improve processing characteristics when an adequate supply of good quality herbage is available. PMID:10376239

O'Brien, B; Dillon, P; Murphy, J J; Mehra, R K; Guinee, T P; Connolly, J F; Kelly, A; Joyce, P

1999-05-01

64

Sheep grazing effect on dryland soil carbon and nitrogen in the wheat-fallow system  

Technology Transfer Automated Retrieval System (TEKTRAN)

Weed control by sheep grazing during fallow periods in the dryland wheat-fallow system may influence soil C and N levels. The effects of fallow management for weed control and soil water conservation [sheep grazing (grazing), herbicide application (chemical), and tillage (mechanical)] and cropping s...

65

Energy Requirements of Grazing Activity  

Technology Transfer Automated Retrieval System (TEKTRAN)

Grazing dairy cows expend more energy than confined dairy cows due to grazing activity as well as walking between the pasture and the milking parlor twice a day. The amount of energy expended depends on a variety of factors, including weather, slope, and distance. This summary article was developed ...

66

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; Petrera, F; Khan, R U; Laudadio, Vito

2011-06-01

67

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. PMID:23316417

Grace, Neville D.; Knowles, Scott O.

2012-01-01

68

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

69

Ultrasonic processing of dairy systems in large scale reactors.  

PubMed

High intensity low frequency ultrasound was used to process dairy ingredients to improve functional properties. Based on a number of lab-scale experiments, several experimental parameters were optimised for processing large volumes of whey and casein-based dairy systems in pilot scale ultrasonic reactors. A continuous sonication process at 20 kHz capable of delivering up to 4 kW of power with a flow-through reactor design was used to treat dairy ingredients at flow rates ranging from 200 to 6000 mL/min. Dairy ingredients treated by ultrasound included reconstituted whey protein concentrate (WPC), whey protein and milk protein retentates and calcium caseinate. The sonication of solutions with a contact time of less than 1 min and up to 2.4 min led to a significant reduction in the viscosity of materials containing 18% to 54% (w/w) solids. The viscosity of aqueous dairy ingredients treated with ultrasound was reduced by between 6% and 50% depending greatly on the composition, processing history, acoustic power and contact time. A notable improvement in the gel strength of sonicated and heat coagulated dairy systems was also observed. When sonication was combined with a pre-heat treatment of 80 degrees C for 1 min or 85 degrees C for 30s, the heat stability of the dairy ingredients containing whey proteins was significantly improved. The effect of sonication was attributed mainly to physical forces generated through acoustic cavitation as supported by particle size reduction in response to sonication. As a result, the gelling properties and heat stability aspects of sonicated dairy ingredients were maintained after spray drying and reconstitution. Overall, the sonication procedure for processing dairy systems may be used to improve process efficiency, improve throughput and develop value added ingredients with the potential to deliver economical benefits to the dairy industry. PMID:19948420

Zisu, Bogdan; Bhaskaracharya, Raman; Kentish, Sandra; Ashokkumar, Muthupandian

2010-08-01

70

e-Cow: an animal model that predicts herbage intake, milk yield and live weight change in dairy cows grazing temperate pastures, with and without supplementary feeding.  

PubMed

This animal simulation model, named e-Cow, represents a single dairy cow at grazing. The model integrates algorithms from three previously published models: a model that predicts herbage dry matter (DM) intake by grazing dairy cows, a mammary gland model that predicts potential milk yield and a body lipid model that predicts genetically driven live weight (LW) and body condition score (BCS). Both nutritional and genetic drives are accounted for in the prediction of energy intake and its partitioning. The main inputs are herbage allowance (HA; kg DM offered/cow per day), metabolisable energy and NDF concentrations in herbage and supplements, supplements offered (kg DM/cow per day), type of pasture (ryegrass or lucerne), days in milk, days pregnant, lactation number, BCS and LW at calving, breed or strain of cow and genetic merit, that is, potential yields of milk, fat and protein. Separate equations are used to predict herbage intake, depending on the cutting heights at which HA is expressed. The e-Cow model is written in Visual Basic programming language within Microsoft Excel®. The model predicts whole-lactation performance of dairy cows on a daily basis, and the main outputs are the daily and annual DM intake, milk yield and changes in BCS and LW. In the e-Cow model, neither herbage DM intake nor milk yield or LW change are needed as inputs; instead, they are predicted by the e-Cow model. The e-Cow model was validated against experimental data for Holstein-Friesian cows with both North American (NA) and New Zealand (NZ) genetics grazing ryegrass-based pastures, with or without supplementary feeding and for three complete lactations, divided into weekly periods. The model was able to predict animal performance with satisfactory accuracy, with concordance correlation coefficients of 0.81, 0.76 and 0.62 for herbage DM intake, milk yield and LW change, respectively. Simulations performed with the model showed that it is sensitive to genotype by feeding environment interactions. The e-Cow model tended to overestimate the milk yield of NA genotype cows at low milk yields, while it underestimated the milk yield of NZ genotype cows at high milk yields. The approach used to define the potential milk yield of the cow and equations used to predict herbage DM intake make the model applicable for predictions in countries with temperate pastures. PMID:22558969

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

2012-06-01

71

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

72

Grazing management and supplementation effects on forage and dairy cow performance on cool-season pastures in the southeastern United States.  

PubMed

Cool-season annual forages provide high-quality herbage for up to 5 mo in the US Gulf Coast states, but their management in pasture-based dairy systems has received little attention. Objectives of this study were to evaluate pasture and animal responses when lactating Holstein cows (n=32, mean DIM=184±21) grazed either N-fertilized rye (Secale cereale L.)-annual ryegrass (Lolium multiflorum Lam.) mixed pastures or rye-annual ryegrass-crimson clover (Trifolium incarnatum L.)-red clover (Trifolium pratense L.) pastures at 2 stocking rates (5 vs. 2.5 cows/ha) and 2 rates of concentrate supplementation [0.29 or 0.40 kg of supplement (as is)/kg of daily milk production]. Two cows paired by parity (one multiparous and one primiparous) were assigned randomly to each pasture. The 2 × 2 × 2 factorial arrangement of treatments was replicated twice in a completely randomized design. Forage mixture and supplementation rate did not affect milk production during three 28-d periods. Greater milk production occurred at the low (19.7 kg/d) than the high (14.7 kg/d) stocking rate during periods 2 and 3, but production was similar during period 1. Despite lower production per cow, milk production per hectare was generally greater at the high stocking rate (81.6 vs. 49.5 kg/ha). Generally, greater pregraze herbage mass on pastures at the lower stocking rate (1,400 vs. 1,150 kg/ha) accounted for greater herbage allowance. Both forage (8.0 vs. 5.9 kg/d) and total (14.1 vs. 11.6) organic matter intake were greater at the low stocking rate. Cows fed less supplement had greater forage organic matter intake (8.0 vs. 6.1 kg/d). Greater herbage mass was associated with the greater intake and subsequent greater milk production. Differences in forage nutritive value, blood metabolites and milk composition, although showing some response to treatments, may not be of sufficient magnitude to affect choice of pasture species or other management practices. Animal performance was not improved by adding clovers to mixed cool-season grass pastures like those in this study. Stocking rate had a major effect on pasture and animal performance. During the cool season, supplementation with concentrates should be planned based on estimated energy intake from forages to achieve optimum milk production and ensure maintenance of body condition. PMID:21787931

Macoon, B; Sollenberger, L E; Staples, C R; Portier, K M; Fike, J H; Moore, J E

2011-08-01

73

Monitoring of nitrogen leaching on a dairy farm during four drainage seasons  

Microsoft Academic Search

3 Teagasc, Moorepark Research Centre, Fermoy, Co. Cork The effect of four commonly used dairy farm management systems (treatments), on nitrogen leaching to 1 m was studied over a 4-year period from October 2001 to April 2005. The treatments were (i) grazed plots receiving dirty water, (ii) 2-cut silage plots receiving slurry, (iii) grazed plots and (iv) 1-cut silage plots

M. Ryan; C. Brophy; J. Connolly; K. McNamara; O. T. Carton

2006-01-01

74

Change in milk production after treatment against gastrointestinal nematodes according to grazing history, parasitological and production-based indicators in adult dairy cows.  

PubMed

To investigate future tools for targeted selective treatment against gastrointestinal nematodes (GIN) in adult dairy cows, we evaluated herd and individual cow factors associated with the post-treatment milk production (MP) response over time. A field trial involving 20 pasturing dairy herds in Western France was conducted in autumn 2010 and autumn 2011. In each herd, lactating cows were randomly allocated to a treatment group (fenbendazole) (623 cows), or a control group (631 cows). Daily cow MP was recorded from 2 weeks before until 10 to 14 weeks after treatment. Individual serum anti-Ostertagia antibody levels (expressed as ODR), pepsinogen levels, faecal egg count (FEC), and bulk tank milk ODR were measured at the time of treatment. Moreover, in each herd, information regarding heifers' grazing and treatment history was collected to assess the Time of Effective Contact (TEC, expressed in months) with GIN infective larvae before the first calving. TEC was expected to reflect the development of immunity against GIN, and TEC=8 months was a cautious threshold over which the resistance to re-infection was expected to be established. Daily MP averaged by week was analyzed using linear mixed models with three nested random effects (cow within herd and herd within year). The overall treatment effect was significant but slight (maximum=+0.85 kg/d on week 6 after treatment), and the evolution of treated cows' MP differed significantly according to several factors. At the herd level, cows from low-TEC herds responded better than cows from high-TEC (? 8 months) herds; cows from herds in which the percentage of positive FEC was >22.6% (median value) responded better than those from herds where it was lower. At the individual cow level, primiparous cows, cows with days in milk (DIM) < or = 100 at the time of treatment, and cows with low individual ODR (< or = 0.38) responded better than multiparous cows, cows with DIM>100, and cows with higher ODR, respectively. These results highlight the variability of the treatment response, suggesting that whole herd anthelmintic treatment are not always appropriate, and propose promising key criteria for targeted selective treatment for GIN in dairy cows. Particularly, the TEC is an original criterion which lends support for a simultaneous on-farm qualitative analysis of grazing management factors. PMID:24468428

Ravinet, N; Bareille, N; Lehebel, A; Ponnau, A; Chartier, C; Chauvin, A

2014-03-17

75

Effects of grazing management system on plant community structure and functioning in a semiarid steppe: scaling from species to community  

Microsoft Academic Search

Under the aim of searching for a more sustainable grazing management system, a mixed management system (grazing and haymaking\\u000a alternate annually) was proposed and tested against traditional management system (used consistently either for grazing or\\u000a haymaking) in the semiarid grassland of Inner Mongolia with a field manipulation experiment. The responses of aboveground\\u000a biomass to the two grazing management systems were

Hongwei Wan; Yongfei Bai; Philipp Schönbach; Martin Gierus; Friedhelm Taube

2011-01-01

76

Dryland Soil Carbon and Nitrogen Influenced by Sheep Grazing in the Wheat-Fallow System  

Technology Transfer Automated Retrieval System (TEKTRAN)

Sheep (Ovis aries L.) grazing during fallow for weed control in wheat (Triticum aestivum L.)-fallow systems may influence soil C and N levels and grain yields by returning part of consumed crop residue to the soil through feces and urine. We evaluated the effects of fallow management [sheep grazing ...

77

Sheep Grazing Effect on Dryland Soil Properties and Wheat Yield in the Wheat-Fallow System  

Technology Transfer Automated Retrieval System (TEKTRAN)

Sheep (Ovis aries L.) grazing during fallow is an effective method of controlling weeds and pests in the wheat (Triticum aestivum L.)-fallow system. Little is known about the effect of sheep grazing on dryland soil properties and wheat yield. We evaluated the effects of fallow management for weed co...

78

Influence of initial milk yield, sward height and concentrate level on herbage intake and grazing behaviour of dairy cattle  

E-print Network

Influence of initial milk yield, sward height and concentrate level on herbage intake and grazing the interrelationship of the sward height, concentrate input and various dependent variables. Two experiments of 42-summer three groups of IMY 22.2, 26.8 and 31.8 kg/day were used. Three sward heights (SH) of 3 - 5 cm, 5 - 7 cm

Paris-Sud XI, Université de

79

Milk production and enteric methane emissions by dairy cows grazing fertilized perennial ryegrass pasture with or without inclusion of white clover.  

PubMed

An experiment was undertaken to investigate the effect of white clover inclusion in grass swards (GWc) compared with grass-only (GO) swards receiving high nitrogen fertilization and subjected to frequent and tight grazing on herbage and dairy cow productivity and enteric methane (CH4) emissions. Thirty cows were allocated to graze either a GO or GWc sward (n=15) from April 17 to October 31, 2011. Fresh herbage [16 kg of dry matter (DM)/cow] and 1 kg of concentrate/cow were offered daily. Herbage DM intake (DMI) was estimated on 3 occasions (May, July, and September) during which 17 kg of DM/cow per day was offered (and concentrate supplementation was withdrawn). In September, an additional 5 cows were added to each sward treatment (n=20) and individual CH4 emissions were estimated using the sulfur hexafluoride (SF6) technique. Annual clover proportion (± SE) in the GWc swards was 0.20 ± 0.011. Swards had similar pregrazing herbage mass (1,800 ± 96 kg of DM/ha) and herbage production (13,110 ± 80 kg of DM/ha). The GWc swards tended to have lower DM and NDF contents but greater CP content than GO swards, but only significant differences were observed in the last part of the grazing season. Cows had similar milk and milk solids yields (19.4 ± 0.59 and 1.49 ± 0.049 kg/d, respectively) and similar milk composition. Cows also had similar DMI in the 3 measurement periods (16.0 ± 0.70 kg DM/cow per d). Similar sward and animal performance was observed during the CH4 estimation period, but GWc swards had 7.4% less NDF than GO swards. Cows had similar daily and per-unit-of-output CH4 emissions (357.1 ± 13.6g of CH4/cow per day, 26.3 ± 1.14 g of CH4/kg of milk, and 312.3 ± 11.5 g of CH4/kg of milk solids) but cows grazing GWc swards had 11.9% lower CH4 emissions per unit of feed intake than cows grazing GO swards due to the numerically lower CH4 per cow per day and a tendency for the GWc cows to have greater DMI compared with the GO cows. As a conclusion, under the conditions of this study, sward clover content in the GWc swards was not sufficient to improve overall sward herbage production and quality, or dairy cow productivity. Although GWc cows had a tendency to consume more and emitted less CH4 per unit of feed intake than GO cows, no difference was observed in daily or per-unit-of-output CH4 emissions. PMID:24393178

Enriquez-Hidalgo, D; Gilliland, T; Deighton, M H; O'Donovan, M; Hennessy, D

2014-03-01

80

Design and Implement of Dairy Mating and Breeding Intelligence Decision Support System Based on Multi-agent  

Microsoft Academic Search

The dairy mating and breeding IDSS introduce a new method in dairy mating work, in the process of dairy mating, the system combine the traditional mating method and person many years experience with the Multi-Agent technology, use ASP.NET principium to develop. This method can play a role of decision support in dairy scientific breeding and genetic improvement of dairy group

Xiaoli Wei; Yonggen Zhang; Jian Sun; Yachun Wu

2009-01-01

81

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

82

Expression of key lipid metabolism genes in adipose tissue is not altered by once-daily milking during a feed restriction of grazing dairy cows.  

PubMed

The objective of this study was to investigate the effect of reduced milking frequency, at 2 feeding levels, on gene expression in adipose tissue of grazing dairy cows during early lactation. Multiparous Holstein-Friesian and Holstein-Friesian × Jersey cows (n=120) were grazed on pasture and milked twice daily (2×) from calving to 34±6d in milk (mean ± standard deviation). Cows were then allocated to 1 of 4 treatments in a 2×2 factorial arrangement. Treatments consisted of 2 milking frequencies (2× or once daily; 1×) and 2 feeding levels for 3 wk: adequately fed (AF), consuming 14.3 kg of dry matter/cow per day, or underfed (UF), consuming 8.3 kg of dry matter/cow per day. After the treatment period, all cows were fed to target grazing residuals ?1,600 kg of DM/cow per day and milked 2× for 20 wk. Adipose tissue was collected from 12 cows per treatment by subcutaneous biopsy at -1, 3, and 5 wk relative to treatment start, RNA was extracted, and transcript abundance of genes involved in lipid metabolism was quantified using a linear mixed model. At the end of the 3-wk treatment period, transcript abundance of genes involved in fatty acid (FA) uptake into adipose tissue (LPL), FA synthesis [FA synthase (FASN) and stearoyl-coenzyme A desaturase (SCD)], FA oxidation [acyl-coenzyme A synthetase long-chain family member 1 (ACSL1) and carnitine palmitoyltransferase 2 (CPT2)], glyceroneogenesis [glycerol-3-phosphate dehydrogenase 1 (GPD1) and pyruvate carboxylase (PC)], and triacylglyceride synthesis [diacylglycerol O-acyltransferase 2 (DGAT2)] were greater in AF1× cows compared with all other treatments. However, when cows were underfed, no effects of milking frequency were observed on transcript abundance of genes involved in adipose lipid metabolism. Despite increases in plasma NEFA concentrations in UF cows, no effects of underfeeding were observed on the transcription of lipolytic genes. At 5 wk, after cows were returned to 2× milking and standard feed allowance, transcript abundances of genes involved in FA synthesis [acetyl-coenzyme A carboxylase ? (ACACA) and SCD)] were increased in cows previously UF. Expression of ACSL1 was decreased in UF1× cows relative to UF2× cows and CPT2 expression was greater in AF1× cows compared with AF2× cows. In conclusion, after 3 wk of reduced milking frequency during a feed restriction, transcription of genes involved in lipid metabolism in adipose tissue were not altered, possibly due to the reduced milk production in these animals. However, 3 wk of 1× milking in AF cows increased transcription of genes involved in FA synthesis, oxidation, and triacylglyceride synthesis. PMID:24119796

Grala, T M; Roche, J R; Phyn, C V C; Rius, A G; Boyle, R H; Snell, R G; Kay, J K

2013-12-01

83

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

84

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. PMID:24223133

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

2013-01-01

85

An unprotected conjugated linoleic acid supplement decreases milk production and secretion of milk components in grazing dairy ewes.  

PubMed

Feeding conjugated linoleic acid (CLA) in a rumen-inert form to dairy ewes has been shown to increase milk production, alter milk composition, and increase the milk fat CLA content. However, few studies have tested ruminally unprotected CLA sources. The objective of this study was to evaluate the effects of an unprotected CLA supplement (29.8% of cis-9,trans-11 and 29.9% of trans-10,cis-12 isomers as methyl esters) on milk yield and composition of dairy ewes. Twenty-four lactating Lacaune ewes were used in a crossover design and received 2 dietary treatments: (1) control: basal diet containing no supplemental lipid and (2) basal diet plus CLA (30 g/d). The CLA supplement was mixed into the concentrate and fed in 2 equal meals after morning and afternoon milkings. Each experimental period consisted of 21 d: 7 d for adaptation and 14 d for data collection. The CLA supplement decreased milk fat content and yield by 31.3 and 38.0%, respectively. Milk yield and secretion of milk lactose and protein were decreased by 8.0, 9.8, and 5.6%, respectively. On the other hand, milk protein content and linear SCC score were 1.8 and 17.7% higher in ewes fed the CLA supplement. The concentration of milk fatty acids originating from de novo synthesis (C16) was increased by 22.6% in ewes fed the CLA supplement. The CLA supplement decreased C14:1/C14:0, C16:1/C16:0, and C18:1/C18:0 desaturase indexes by 25, 18.7, and 0.1%, respectively, but increased the cis-9,trans-11 CLA/trans-11 C18:1 ratio by 8.6%. The concentrations of trans-10,cis-12 CLA and cis-9,trans-11 CLA in milk fat was 309 and 33.4% higher in ewes fed CLA. Pronounced milk fat depression coupled with the deleterious effects on milk yield, milk SCC, and secretion of all milk solids observed in ewes fed an unprotected CLA supplement is likely to be associated with high doses of trans-10,cis-12 CLA reaching the mammary gland, corroborating previous results obtained with dairy cows. PMID:22365226

Oliveira, D E; Gama, M A S; Fernandes, D; Tedeschi, L O; Bauman, D E

2012-03-01

86

Systems physiology in dairy cattle: nutritional genomics and beyond.  

PubMed

Microarray development changed the way biologists approach the holistic study of cells and tissues. In dairy cattle biosciences, the application of omics technology, from spotted microarrays to next-generation sequencing and proteomics, has grown steadily during the past 10 years. Omics has found application in fields such as dairy cattle nutritional physiology, reproduction, and immunology. Generating biologically meaningful data from omics studies relies on bioinformatics tools. Both are key components of the systems physiology toolbox, which allows study of the interactions between a condition (e.g., nutrition, physiological state) with tissue gene/protein expression and the associated changes in biological functions. The nature of physiologic and metabolic adaptations in dairy cattle at any stage of the life cycle is multifaceted, involves multiple tissues, and is dynamic, e.g., the transition from late-pregnancy to lactation. Application of integrative systems physiology in periparturient dairy cattle has already advanced knowledge of the simultaneous functional adaptations in liver, adipose, and mammary tissue. PMID:25387024

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

2013-01-01

87

Habitat relationships of eastern red-backed salamanders ( Plethodon cinereus) in Appalachian agroforestry and grazing systems  

Microsoft Academic Search

Woodland salamander responses to either traditional grazing or silvopasture systems are virtually unknown. An information-theoretic modelling approach was used to evaluate responses of red-backed salamanders (Plethodon cinereus) to silvopasture and meadow conversions in southern West Virginia. Searches of area-constrained plots and artificial coverboards that were distributed across a gradient of agricultural conversion and grazing intensity, including hardwood silvopastures, hay meadows,

Breanna L. Riedel; Kevin R. Russell; W. Mark Ford; Katherine P. O’Neill; Harry W. Godwin

2008-01-01

88

Productivity and hay requirements of beef cattle in a Midwestern year-round grazing system.  

PubMed

Our objective was to evaluate a replicated (n = 2) Midwestern year-round grazing system's hay needs and animal production compared with a replicated (n = 2) conventional (minimal land) system over 3 yr. Because extended grazing systems have decreased hay needs for the beef herd, it was hypothesized that this year-round system would decrease hay needs without penalizing animal production. In the minimal land (ML) system, two replicated 8.1-ha smooth bromegrass-orchardgrass-birdsfoot trefoil (SB-OG-BFT) pastures were rotationally stocked with six mature April-calving cows and calves and harvested as hay for winter feeding in a drylot. After weaning, calves were finished on a high-concentrate diet. Six mature April-calving cows, six mature August-calving cows, and their calves were used in the year-round (YR) grazing system. During the early and late summer, cattle grazed two replicated 8.1-ha SB-OG-BFT pastures by rotational stocking. In mid-summer and winter, April- and August-calving cows grazed two replicated 6.1-ha, endophyte-free tall fescue-red clover (TF-RC) and smooth bromegrass-red clover (SB-RC) pastures, respectively, by strip-stocking. In late autumn, spring-calving cows grazed 6.1-ha corn crop residue fields by strip-stocking. Calves were fed hay with corn gluten feed or corn grain over winter and used as stocker cattle to graze SB-OG-BFT pastures with cows until early August the following summer. First-harvest forage from the TF-RC and SB-RC pastures was harvested as hay. Body condition scores of April-calving cows did not differ between grazing systems, but were lower (P < or = 0.03) than those of August-calving cows from mid-gestation through breeding. Preweaning calf BW gains were 47 kg/ha of perennial pasture (P < 0.01) and 32 kg/cow (P = 0.01) lower in the YR grazing system than in the ML system. Total BW gains ofpreweaning calf and grazing stocker cattle were 12 kg/ha of perennial pasture less (P = 0.07), but 27 kg/cow greater (P = 0.02) in pastures in the YR grazing system than in the ML system. Amounts of hay fed to cows in the ML system were 1,701 kg DM/cow and 896 kg DM/cow-stocker pair greater (P < 0.05) than in the YR grazing system. Extended grazing systems in the Midwest that include grazing of stocker cattle to utilize excess forage growth will decrease stored feed needs, while maintaining growing animal production per cow in April- and August-calving herds. PMID:15318752

Janovick, N A; Russell, J R; Strohbehn, D R; Morrical, D G

2004-08-01

89

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

90

Implications of dairy systems on enteric methane and postulated effects on total greenhouse gas emission.  

PubMed

The effects of feeding total mixed ration (TMR) or pasture forage from a perennial sward under a management intensive grazing (MIG) regimen on grain intake and enteric methane (EM) emission were measured using chambers. Chamber measurement of EM was compared with that of SF6 employed both within chamber and when cows grazed in the field. The impacts of the diet on farm gate greenhouse gas (GHG) emission were also postulated using the results of existing life cycle assessments. Emission of EM was measured in gas collection chambers in Spring and Fall. In Spring, pasture forage fiber quality was higher than that of the silage used in the TMR (47.5% v. 56.3% NDF; 24.3% v. 37.9% ADF). Higher forage quality from MIG subsequently resulted in 25% less grain use relative to TMR (0.24 v. 0.32 kg dry matter/kg milk) for MIG compared with TMR. The Fall forage fiber quality was still better, but the higher quality of MIG pasture was not as pronounced as that in Spring. Neither yield of fat-corrected milk (FCM) which averaged 28.3 kg/day, nor EM emission which averaged 18.9 g/kg dry matter intake (DMI) were significantly affected by diet in Spring. However, in the Fall, FCM from MIG (21.3 kg/day) was significantly lower than that from TMR (23.4 kg/day). Despite the differences in FCM yield, in terms of EM emission that averaged 21.9 g/kg DMI was not significantly different between the diets. In this study, grain requirement, but not EM, was a distinguishing feature of pasture and confinement systems. Considering the increased predicted GHG emissions arising from the production and use of grain needed to boost milk yield in confinement systems, EM intensity alone is a poor predictor of the potential impact of a dairy system on climate forcing. PMID:23896042

Fredeen, A; Juurlink, S; Main, M; Astatkie, T; Martin, R C

2013-11-01

91

Comparison of management intensive grazing and continuous grazing in beef cattle pasture  

Technology Transfer Automated Retrieval System (TEKTRAN)

Management intensive grazing (MIG) offers the potential to increase the financial profitability and productivity of grazing beef and dairy farms in Appalachian Ohio, with minimum environmental impacts. The objective of the project was to compare MIG with conventional continuous grazing (CG) and rela...

92

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

93

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

94

BLOW UP AND GRAZING COLLISION IN VISCOUS FLUID SOLID INTERACTION SYSTEMS  

E-print Network

BLOW UP AND GRAZING COLLISION IN VISCOUS FLUID SOLID INTERACTION SYSTEMS MATTHIEU HILLAIRET, TAK´EO TAKAHASHI Abstract. In this paper we investigate finite time blow up of strong solutions to the system. Introduction In this paper, we compute blowing-up solutions for the classical fluid solid interaction system

Paris-Sud XI, Université de

95

BLOW UP AND GRAZING COLLISION IN VISCOUS FLUID SOLID INTERACTION SYSTEMS  

E-print Network

BLOW UP AND GRAZING COLLISION IN VISCOUS FLUID SOLID INTERACTION SYSTEMS MATTHIEU HILLAIRET AND TAK. Introduction In this paper, we compute blowing-up solutions for a fluid solid interaction system. We consider´EO TAKAHASHI Abstract. We investigate qualitative properties of strong solutions to a classical system

Hillairet, Matthieu

96

Ammonia emission model for whole farm evaluation of dairy production systems.  

PubMed

Ammonia (NH) emissions vary considerably among farms as influenced by climate and management. Because emission measurement is difficult and expensive, process-based models provide an alternative for estimating whole farm emissions. A model that simulates the processes of NH formation, speciation, aqueous-gas partitioning, and mass transfer was developed and incorporated in a whole farm simulation model (the Integrated Farm System Model). Farm sources included manure on the floor of the housing facility, manure in storage (if used), field-applied manure, and deposits on pasture (if grazing is used). In a comprehensive evaluation of the model, simulated daily, seasonal, and annual emissions compared well with data measured over 2 yr for five free stall barns and two manure storages on dairy farms in the eastern United States. In a further comparison with published data, simulated and measured barn emissions were similar over differing barn designs, protein feeding levels, and seasons of the year. Simulated emissions from manure storage were also highly correlated with published emission data across locations, seasons, and different storage covers. For field applied manure, the range in simulated annual emissions normally bounded reported mean values for different manure dry matter contents and application methods. Emissions from pastures measured in northern Europe across seasons and fertilization levels were also represented well by the model. After this evaluation, simulations of a representative dairy farm in Pennsylvania illustrated the effects of animal housing and manure management on whole farm emissions and their interactions with greenhouse gas emissions, nitrate leaching, production costs, and farm profitability. PMID:25603063

Rotz, C Alan; Montes, Felipe; Hafner, Sasha D; Heber, Albert J; Grant, Richard H

2014-07-01

97

Assessment of heifer grazing experience on short-term adaptation to pasture and performance as lactating cows.  

PubMed

A 3-yr study evaluated the carryover effects of dairy heifer grazing experience on behavior and first-lactation performance as dairy cows. Forty-one Holstein and 23 Holstein-Jersey crossbred calves born between January and April 2008 were randomly assigned to 1 of 4 treatments (n=8 per group, 2 groups per treatment) in a completely randomized design. Treatments were combinations of managing dairy heifers in confinement (CNF) or on pasture (PST): grazed yr 1 and 2 (PSTPST); grazed yr 1, but confined yr 2 (PSTCNF); confined yr 1 and grazed yr 2 (CNFPST); or confined yr 1 and 2 (CNFCNF). After calving, all heifers on all treatments were grazed as cows in yr 3. In yr 1, PSTPST and PSTCNF heifers were grazed for 41 d on Italian ryegrass pastures, whereas CNFPST and CNFCNF were housed in bedded-pack pens and fed a TMR. In yr 2, PSTPST and CNFPST heifers grazed Italian ryegrass pasture for 65 d, whereas PSTCNF and CNFCNF remained in confinement. In yr 2, a mid-trial assessment of heifer grazing behavior was made on PSTPST versus CNFPST heifers. Grazing activities were assessed by visual observation and heifer movement measured by portable global positioning system units. Heifers from all treatment groups subsequently calved between January and April in yr 3. All primiparous cows were then allocated to pastures by treatment group, grazed for 61 d, (May through July) in yr 3, with grazing behavior and milk production evaluated while grazing. In yr 2, heifers on the PSTPST treatment spent more time grazing than heifers on the CNFPST treatment (78 vs. 35% of the time) when first exposed to pasture (d 1). On d 1 to 3, PSTPST heifers walked a greater distance than CNFPST heifers; however, PSTPST and CNFPST heifers had similar daily grazing times and walking patterns after 3 d of pasture exposure in yr 2. As lactating cows (yr 3), cows with no (CNFCNF) grazing experience grazed less on d 1 compared with cows with (PSTPST, PSTCNF, or CNFPST) grazing experience. Day-1 grazing times in yr 3 were 62, 59, 76, and 13% of the times for cows with PSTPST, PSTCNF, CNFPST, and CNFCNF grazing experience, respectively. In yr 3, on d 1 to 3, cows with previous grazing experience as heifers (PSTPST, CNFPST, and PSTCNF) walked a greater distance than cows without previous grazing experience (CNFCNF). Milk production was lowest on d 1 to 3 for cows with no previous grazing experience (CNFCNF), but average daily milk production was not different overall over the 61 d of study in yr 3. Results indicate that grazing experiences as a heifer can affect behavior and milk production during a cow's first days on pasture. After a short acclimation period, dairy cows without grazing experience as heifers developed similar grazing behaviors and performance as cows with grazing experience as heifers. PMID:23522679

Lopes, F; Coblentz, W; Hoffman, P C; Combs, D K

2013-05-01

98

Integrating sheep grazing into wheat-fallow systems: Crop yield and soil properties  

Technology Transfer Automated Retrieval System (TEKTRAN)

The two predominant systems for weed management in summer fallow are tillage with a field cultivator or multiple applications of broad spectrum herbicides with zero tillage. Both systems are based on substantial use of off farm resources. Strategic grazing of sheep may allow grain growers to more ...

99

Grass Grows, the Cow Eats: A Simple Grazing Systems Model with Emergent Properties  

ERIC Educational Resources Information Center

We describe a simple, yet intellectually challenging model of grazing systems that introduces basic concepts in ecology and systems analysis. The practical is suitable for high-school and university curricula with a quantitative orientation, and requires only basic skills in mathematics and spreadsheet use. The model is based on Noy-Meir's (1975)…

Ungar, Eugene David; Seligman, Noam G.; Noy-Meir, Imanuel

2004-01-01

100

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

101

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].

102

Methods for exploring management options to reduce greenhouse gas emissions from tropical grazing systems  

Microsoft Academic Search

Increasing atmospheric concentrations of ‘greenhouse gases’ are expected to result in global climatic changes over the next decades. Means of evaluating and reducing greenhouse gas emissions are being sought. In this study an existing simulation model of a tropical savanna woodland grazing system was adapted to account for greenhouse gas emissions. This approach may be able to be used in

S. Mark Howden; David H. White; Greg M. Mckeon; Joe C. Scanlan; John O. Carter

1994-01-01

103

Grazing Strategies for Beef Production Escalating energy costs and alternative cropping systems for biofuels production have  

E-print Network

Grazing Strategies for Beef Production Escalating energy costs and alternative cropping systems with pasture-feedlot manage-· ment alternatives. Assess economic implications of beef production using an array character- istics of beef that may provide an alternative lean-to-fat composition for consum- ers. http

104

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

105

Diet quality and diet selection of steers grazing in a rotational system at four levels of forage  

E-print Network

Diet quality and diet selection of steers grazing in a rotational system at four levels of forage corniculatus L. at the Experimental Agronomic Station EEMAC, Uruguay, to study diet quality and to provide an understanding of how the rapid defoliation that occurs under rotational grazing affects diet selection. Four

Paris-Sud XI, Université de

106

Effects of a short duration grazing system on white-tailed deer (Odocoileus virginianus) in the Rio Grande Plain, Texas  

E-print Network

the influence of grazing periods in a short duration grazing system on deer use patterns. Pellet group sampling stations were established on s, six-pasture, one-herd. , short duration system, snd a one-pasture, one-herd. , year-long grazed system. The short... chip counts on established pellet group stations. On the short duration system, total cow use on tame pastures was 5. 9 times greater than native range, s. erially sprayed a, eas were used 2. 6 +imes more then native range and shredded areas were...

Allred, Kevin Leigh

2012-06-07

107

The effects of milking frequency in early lactation on milk yield, mammary cell turnover, and secretory activity in grazing dairy cows.  

PubMed

In dairy cows, short-term changes of milking frequency in early lactation have been shown to produce an immediate and a long-term effect on milk yield in stall-fed cows. The effect is controlled locally within mammary glands and could be a function of either secretory mammary epithelial cell number or activity. To resolve this and determine its applicability in other feed management systems, a unilateral milking frequency experiment was conducted with udder halves of 17 multiparous, pasture-fed dairy cows milked either 4 times (4×) or once a day (1×) for 14d from 5±2d in milk. Mean half-udder milk yield during the treatment period was higher from the 4× compared with 1× udder halves and continued to be higher until 200d in milk once returned to twice a day milking. Mammary biopsies were obtained on d 14 of treatment from both udder halves of 10 cows. Proliferation of mammary cells was higher in 4× udder halves compared with 1×, whereas no difference in apoptosis levels was detected. Abundance of ?S1-casein, ?-casein, ?-lactalbumin, and ?-lactoglobulin mRNA was higher in tissue samples from 4× udder halves compared with 1×, whereas lactoferrin mRNA abundance was lower in 4× udder halves. In summary, change in milking frequency during early lactation affects proliferation of mammary cells as well as expression of the major milk protein genes, which both contribute to the observed changes in milk yield during and after unilateral milking frequency treatment. PMID:25465535

Murney, R; Stelwagen, K; Wheeler, T T; Margerison, J K; Singh, K

2015-01-01

108

DAFOSYM: A Dairy Forage System Model for Evaluating Alternatives in Forage Conservation1  

Microsoft Academic Search

The dairy forage system model, DAFOSYM, is a simulation model designed to evaluate technologies and management strategies on representa- tive dairy farms. The model integrates crop growth, harvest, storage, feeding, animal utilization, and economic analy- sis. Corn and alfalfa growth are simu- lated using historical weather data. Alfalfa harvest includes mowing, field curing, raking, baling, and chopping; losses and quality

C. Alan Rotz; Dennis R. Buckmaster; David R. Mertens; J. Roy Black

1989-01-01

109

A model system for evaluating surface disinfection in dairy factory environments  

Microsoft Academic Search

A model system was developed for evaluating the efficacy of disinfectants for inactivating bacteria present in biofilms on surfaces within dairy factory environments. Mixed culture biofilms of six dairy factory isolates (pseudomonads, coliforms and presumptive staphylococci) were generated on factory floor tiles and subjected to up to three fouling and cleaning (FC) cycles. Disinfectants (hypochlorite, peroxyacetic acid-, acid anionic- and

G. C. Knight; H. M. Craven

2010-01-01

110

Incorporating grazing into an eco-hydrologic model: Simulating coupled human and natural systems in rangelands  

NASA Astrophysics Data System (ADS)

Rangelands provide an opportunity to investigate the coupled feedbacks between human activities and natural ecosystems. These areas comprise at least one-third of the Earth's surface and provide ecological support for birds, insects, wildlife and agricultural animals including grazing lands for livestock. Capturing the interactions among water, carbon, and nitrogen cycles within the context of regional scale patterns of climate and management is important to understand interactions, responses, and feedbacks between rangeland systems and humans, as well as provide relevant information to stakeholders and policymakers. The overarching objective of this research is to understand the full consequences, intended and unintended, of human activities and climate over time in rangelands by incorporating dynamics related to rangeland management into an eco-hydrologic model that also incorporates biogeochemical and soil processes. Here we evaluate our model over ungrazed and grazed sites for different rangeland ecosystems. The Regional Hydro-ecologic Simulation System (RHESSys) is a process-based, watershed-scale model that couples water with carbon and nitrogen cycles. Climate, soil, vegetation, and management effects within the watershed are represented in a nested landscape hierarchy to account for heterogeneity and the lateral movement of water and nutrients. We incorporated a daily time-series of plant biomass loss from rangeland to represent grazing. The TRY Plant Trait Database was used to parameterize genera of shrubs and grasses in different rangeland types, such as tallgrass prairie, Intermountain West cold desert, and shortgrass steppe. In addition, other model parameters captured the reallocation of carbon and nutrients after grass defoliation. Initial simulations were conducted at the Curlew Valley site in northern Utah, a former International Geosphere-Biosphere Programme Desert Biome site. We found that grasses were most sensitive to model parameters affecting the daily-to-yearly ratio of net primary productivity allocation of carbon, non-structural carbohydrate pool, rate of root turnover, and leaf on/off days. We also ran RHESSys over AmeriFlux sites representing a spectrum of rangeland ecosystems, such as at Konza Prairie (Kansas), Fort Peck (Montana), and Corral Pocket (Utah), as well as grazed versus ungrazed sites. We evaluated RHESSys using net ecosystem exchange . Competition between rangeland vegetation types with different physiological parameters, such as carbon:nitrogen ratio and specific leaf area within a single site were also tested. Preliminary results indicated both species-specific parameters and allocation controls were important to capturing the ecosystem response to environmental conditions. Furthermore, the addition of a grazing component allowed us to better capture impacts of management at grazed sites. Future research will involve incorporation of other grazing processes, such as impacts of excreta and increased nutrient availability and cycling.

Reyes, J. J.; Liu, M.; Tague, C.; Choate, J. S.; Evans, R. D.; Johnson, K. A.; Adam, J. C.

2013-12-01

111

Methane emissions measured directly from grazing livestock in New Zealand  

Microsoft Academic Search

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

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

1997-01-01

112

Heifer development systems: dry-lot feeding compared with grazing dormant winter forage.  

PubMed

Two hundred ninety-nine Angus-based, nulliparous heifers (253 ± 2 kg initial BW) from 3 production years were utilized to compare traditional postweaning dry lot (DL) development with a more extensive winter grazing system utilizing a combination of corn residue and winter range (EXT). Heifers developed in the DL were offered a common diet after the weaning period for 208 d in yr 1, 194 d in yr 2, and 150 d in yr 3 until breeding. Heifers developed in EXT grazed corn residue for 135 d in yr 1, 106 d in yr 2, and 91 d in yr 3, and then fed in the DL until breeding (yr 1) or grazed dormant winter grass for approximately 60 d before being fed in the DL (yr 2 and 3). All 3 years, heifers were estrus synchronized, with timed AI performed in yr 1. In yr 2 and 3, estrus was detected and those detected in estrus were artificially inseminated approximately 12 h later. Heifers were exposed to bulls 10 d after the last AI for 60 d while grazing summer pasture. During the winter grazing period, EXT heifers gained less (P = 0.01) BW than DL heifers and EXT heifers had lighter (P = 0.02) BW at breeding. Fewer (P < 0.01) EXT heifers reached puberty before breeding. Conception to AI was not different (P = 0.23); however, AI pregnancy rate tended (P = 0.08) to be less in EXT heifers. Final pregnancy rates were not different (P = 0.38) between treatment groups. Although EXT heifers had lighter (P = 0.02) BW at pregnancy diagnosis; however, they did compensate with greater (P = 0.05) ADG after breeding, resulting in similar (P = 0.22) precalving BW. Winter development system did not influence (P > 0.10) percentage of calving in the first 21 d, calf birth date, and calf birth BW, or dystocia score. Pregnancy rate after the second breeding season was not different (P = 0.56) between treatments. Heifer development using extended winter grazing reduced (P < 0.01) the cost of producing a pregnant heifer by $45 compared with DL. PMID:21521820

Funston, R N; Larson, D M

2011-05-01

113

Effect of crude degummed canola oil and ad libitum grazing on plasma metabolites of primiparous Holstein-Friesian cows in a pasture-based system.  

PubMed

BackgroundThe supplementation of fat to lactating dairy cows has long been used as a management tool to increase dietary energy density for improving cow production, reproduction and to alleviate negative energy balance. Attempts have been made to investigate the effect of canola meal on plasma metabolites in lactating cows, but the results have been diverse and inconsistent. To our current knowledge, there is a dearth of published information on the utilization of Crude Degummed Canola Oil (CDCO) in pasture-based dairy systems. Therefore, the objective of this study was to investigate the changes in plasma metabolite profiles of pasture-based, primiparous, Holstein-Friesian cows supplemented with varying dietary levels of CDCO for eight weeks. The study tested the hypothesis that feeding grazing primiparous Holstein-Friesian cows for eight weeks with incremental levels of CDCO supplement will decrease plasma non-esterified fatty acids (NEFA) and ß-hydroxybutyrate (BHBA), but increase plasma cholesterol and glucose metabolites. ResultsTwenty lactating primiparous Holstein-Friesian cows 40 days in milk were randomly allotted into four treatment groups that consisted of a wheat-based, pelleted basal diet with no supplemental CDCO (control), basal diet with CDCO added at 25 ml/kgDM (DM; dry matter) (low), 35 ml/kgDM (medium) and 50 ml/kgDM (high) in an eight-week feeding trial, after two weeks of adjustment. Treatment influenced BHBA but had no effect on plasma NEFA, cholesterol and glucose metabolite profiles (P¿>¿0.05). However, week of supplementation had a significant effect (P¿<¿0.05) on BHBA, NEFA and glucose concentrations.ConclusionsWe concluded that with the exception of BHBA, CDCO at current levels of supplementation does not alter the plasma metabolite profiles of grazing primiparous cows. The lack of significant differences across treatments seems to indicate that higher levels of CDCO than the current levels used in this study, are probably needed. Furthermore, the duration of supplementation with CDCO had a greater impact on plasma metabolites than the levels of supplementation. Our findings also suggest that primiparous cows grazing high quality pastures during spring have sufficient energy intakes to prevent negative energy balance at 40 days in milk without the need for added fat supplements. PMID:25253446

Otto, John R; Malau-Aduli, Bunmi S; Balogun, Razaq O; Nish, Peter; Malau-Aduli, Aduli E O

2014-09-26

114

Effect of prior grazing experiences on grazing behavior and performance of lactating cows  

Technology Transfer Automated Retrieval System (TEKTRAN)

The impact of grazing experiences early in life on grazing behavior and performance of lactating dairy heifers was evaluated in a 3-year study. Sixty-four Holstein and Holstein x Jersey calves were randomly assigned to one of 4 treatments (n = 16) in 2008. Treatments were combinations of managing he...

115

Biological and environmental efficiency of high producing dairy systems through application of life cycle analysis   

E-print Network

Dairy production systems are an important global contributor to anthropogenic greenhouse gas (GHG) emissions including methane (CH4), nitrous oxide (N2O) and carbon dioxide (CO2). Due to the role GHG play in climate ...

Ross, Stephen Alexander

2014-11-27

116

Chapter 14: Incorporating targeted grazing into farming systems  

Technology Transfer Automated Retrieval System (TEKTRAN)

Cropping systems were once wholly integrated with livestock production, but today, few cropping systems include livestock. Sheep and goats traditionally produced on rangelands or pasture forages and supplemented with harvested feeds during winter. We present concepts and specific areas whereby gra...

117

Livestock Production and Profitability Comparisons of Various Grazing Systems, Texas Range Station.  

E-print Network

system. The two single use systems both lost money in ,964. Annual income for the yearlong cattle only treatnlent ranged from a loss of $1 1.88 per A.U. to :gin of S39.98, and income for the yearlong sheep :!I\\ ~anged from a loss of $1.44 to a gain... with a common stocking rate of 25.6 animal units per section. 'The systems compared were: yearlong graz- ing with cattle only and with sheep only; yearlong grazing with both cattle and sheep; and a two- pasture rotation and a four-pasture rotation...

Huss, Donald L.; Allen, Jerry V.

1969-01-01

118

Grazing incidence and multilayer x-ray optical systems  

Microsoft Academic Search

The development of x-ray optics for astrophysical investigations in the 40 - 100 keV energy range is extremely important. In this energy range, a focusing system is necessary to resolve crowded regions, to improve sensitivity, and to provide the deep sky images necessary to make the next great step forward in this field. Such a step was ably demonstrated by

Melville P. Ulmer; Robert I. Altkorn; Allen S. Krieger; Daniel R. Parsignault; Yip-Wah Chung

1997-01-01

119

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

120

Evaluation of a lameness scoring system for dairy cows.  

PubMed

Lameness is a major problem in dairy production both in terms of reduced production and compromised animal welfare. A 5-point lameness scoring system was developed based on previously published systems, but optimized for use under field conditions. The scoring system included the words "in most cases" in the descriptions of the clinical signs evaluated. This was done to avoid a situation in which cows might not fit into any of the categories. Additionally, a number of clinical signs used in other lameness scoring systems, considered of less importance in relation to lameness, were not included. Only clinical signs were included that could easily be assessed within a few seconds from a distance. The scoring system was evaluated with intra-and interobserver agreement using kappa statistics. The evaluation was done before and after training 5 observers. Weighted kappa values ranged from 0.38 to 0.78 for intraobserver agreement, with mean kappa values across all observers of 0.60 and 0.53 before and after training, respectively. Weighted kappa values ranged from 0.24 to 0.68 for interobserver agreement, with mean kappa values across all pairs of observers of 0.48 and 0.52 before and after training, respectively. Training had only a limited positive effect on intra- and interobserver agreement. Additionally, how the different lameness categories are distributed along a theoretical scale representing the full spectrum of lameness from "absolutely normal gait" to "as lame as a cow can possibly be" was evaluated. This evaluation was done using the polychoric correlation coefficient. The estimated within-observer polychoric correlation coefficient ranged from 0.76 to 0.96, and there were no significant differences between the thresholds used to classify cows into different lameness categories by different observers before or after training. In conclusion, the results suggest that the lameness categories were not equidistant and the scoring system has reasonable reliability in terms of intra- and interobserver agreement. PMID:18096932

Thomsen, P T; Munksgaard, L; Tøgersen, F A

2008-01-01

121

Manure nitrogen excretion and transformation on dairy farms  

Technology Transfer Automated Retrieval System (TEKTRAN)

Nitrogen (N) passes through a continuing cycle on dairy farms. On confinement farms, cows are fed conserved forages, grain, protein and mineral supplements, and manure is collected, stored and applied to cropland. Grazing-based dairy farms use intensive rotational grazing to provide fresh forage, ge...

122

Effects of stocking rate on pasture production, milk production and reproduction of supplemented crossbred Holstein–Jersey dairy cows grazing lucerne pasture  

Microsoft Academic Search

Effects of stocking rates of 1.6, 2.1 and 2.6cows\\/ha on farm efficiency were evaluated using 92 crossbred Holstein–Jersey cows in a completely randomised design for 2yr in Argentina. A 44.1ha farm was divided into three farmlets and one spring calving herd was allocated to each. Cows grazed on lucerne based pastures (Medicago sativa L.) and were supplemented with high tannin

J. Baudracco; N. Lopez-Villalobos; L. A. Romero; D. Scandolo; M. Maciel; E. A. Comeron; C. W. Holmes; T. N. Barry

2011-01-01

123

Minimising surface water pollution resulting from farm?dairy effluent application to mole?pipe drained soils. II. The contribution of preferential flow of effluent to whole?farm pollutant losses in subsurface drainage from a West Otago dairy farm  

Microsoft Academic Search

To evaluate the role of artificial drainage systems in the transfer of nutrients and faecal organisms from soil to waterways, mole?pipe drainage flows were monitored from two large (27 × 40 m), hydrologically isolated field plots that were part of a long?term dairy pasture in West Otago, New Zealand. One plot was grazed only whilst the other plot was spray

R. M. Monaghan; L. C. Smith

2004-01-01

124

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

125

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

126

Evaluating Technologies for Reducing Nutrients in Dairy Effluent The Geotube Dewatering System  

E-print Network

Evaluating Technologies for Reducing Nutrients in Dairy Effluent The Geotube® Dewatering System in the North Bosque and Leon River Watersheds. In 2005, they evaluated the Geotube® de-watering system The Geotube® dewatering system was demonstrated by the Miratech Division of Ten Cate Nicolon and General

Mukhtar, Saqib

127

Methane emissions from a New Mexico dairy lagoon system  

Technology Transfer Automated Retrieval System (TEKTRAN)

Methane is a greenhouse gas with a global warming potential 25 times that of carbon dioxide. Animal agriculture is recognized as a significant source of methane to the atmosphere. Dairies on the Southern High Plains of New Mexico and Texas are typically open lot, and major sources of methane are the...

128

Grazing and feedlot performance of yearling stocker cattle integrated with spring- and fall-calving beef cows in a year-round grazing system.  

PubMed

Effects of calving season and finishing system on forage and concentrate consumption and carcass characteristics of calves were compared. In each of 3 yr, two replicates of three growing and finishing systems were compared including 1) spring calves finished on a high-grain diet in a feedlot immediately post-weaning (WF); 2) spring calves backgrounded on a hay-corn gluten diet over winter for 179 +/- 18 d after weaning, grazed for 98 +/- 9 d in cool-season grass-legume pastures, and finished on a high-grain diet in a feedlot (SGF); and 3) fall calves backgrounded on a hay-corn gluten feed diet over winter for 69 +/- 31 d after weaning, grazed for 98 +/- 9 d in cool-season grass-legume pastures, and finished on a high-grain diet in a feedlot (FGF). During the grazing phase, calves on the SGF and FGF treatments were equally stocked with spring-calving cow-calf pairs before grazing by pregnant fall-calving cows in a first-last rotational stocking system at a rate of 1.9 standard livestock units/ha. As designed, retained calves in the FGF system spent 110 fewer days in the drylot during backgrounding than retained calves in the SGF system (P = 0.01), resulting in less feed provided during winter. A greater (P < 0.01) quantity of hay was fed to SGF calves after weaning over winter (1,305 kg of DM per calf) than the quantity fed to FGF calves (305 kg of DM per calf). Quantity of grain (including commercial starter) fed to SGF calves after weaning did not differ (P = 0.28) from that fed to FGF calves (126 vs. 55 kg of DM per calf); however, calves in the FGF system required 80 and 71 kg of DM per calf more concentrate to finish to an equivalent external fat thickness compared with SGF and WF calves, respectively (P = 0.02). Average daily gains in the feedlot were greater (P < 0.01) for SGF and FGF calves than for WF calves during all 3 yr. There were no differences (P = 0.69) in carcass quality grades among calves in all groups, but SGF calves had greater (P < 0.01) hot carcass weight and LM area measurements at slaughter than FGF or WF calves. Although calves in the FGF system were 25 kg lighter than calves in the WF system at slaughter (P = 0.03), and had a lower dressing percent (P = 0.03), other carcass characteristics did not differ between these two groups. Lower stored-feed requirements and similar carcass quality characteristics made retention of a fall calf crop advantageous over retention of a spring calf crop for use as stocker animals before finishing. PMID:16230669

Guretzky, N A Janovick; Russell, J R; Strohbehn, D R; Morrical, D G

2005-11-01

129

The botanical composition of cattle diets on a 7-pasture high-intensity low-frequency grazing system  

E-print Network

THE BOTANICAL COMPOSITION OF CATTLE DIETS ON A 7-PASTURE HIGH-INTENSITY LOW-FREQUENCY GRAZING SYSTEM A Thesis by CHARLES ANDREW TAYLOR, JR. Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement... for the degree of MASTER OF SCIENCE May, 1973 MaJor SubJect: Range Science THE BOTANICAL COYiPOSITION OF CATTLE DIETS ON A 7-PASTI|RE HIGH-INTENSITY LOW-FREQUENCY GRAZING SYSTFM A Thesis by CHARLES ANDREW TAYLOR, JR. Approved as to style and content by...

Taylor, Charles Andrew

2012-06-07

130

A Dairy Cow Body Condition Scoring System and Its Relationship to Selected Production Characteristics  

Microsoft Academic Search

A scoring system with 1 to 5 scale was devised to measure body condition of dairy cows at any point during the lactation cycle. Cows were scored on appearance and palpation of back and hind quarters only. Relationships of body weight, frame size measurements, milk production, and characteristics related to the body condition scoring system were determined. During 18 too,

E. E. Wildman; G. M. Jones; P. E. Wagner; R. L. Boman; H. F. Troutt Jr.; T. N. Lesch

1982-01-01

131

Performance of temperature-phased anaerobic digestion (TPAD) system treating dairy cattle wastes  

Microsoft Academic Search

The performance of temperature-phased anaerobic digestion (TPAD) system in the stabilization of dairy cattle wastes at high solids concentrations has never been evaluated, though the process has been established as a feasible alternative to conventional mesophilic processes for the treatment of municipal wastewater sludges. In this study, the TPAD system operating at a retention time of 14 days was subjected

Shihwu Sung; Harikishan Santha

2003-01-01

132

Characterization of Dutch dairy farms using sensor systems for cow management.  

PubMed

To improve cow management in large dairy herds, sensors have been developed that can measure physiological, behavioral, and production indicators on individual cows. Recently, the number of dairy farms using sensor systems has increased. It is not known, however, to what extent sensor systems are used on dairy farms, and the reasons why farmers invest or not in sensor systems are unclear. The first objective of this study was to give an overview of the sensor systems currently used in the Netherlands. The second objective was to investigate the reasons for investing or not investing in sensor systems. The third objective was to characterize farms with and without sensor systems. A survey was developed to investigate first, the reasons for investing or not in sensor systems and, then, how the sensor systems are used in daily cow management. The survey was sent to 1,672 Dutch dairy farmers. The final data set consisted of 512 dairy farms (response rate of 30.6%); 202 farms indicated that they had sensor systems and 310 farms indicated that they did not have sensor systems. A wide variety of sensor systems was used on Dutch dairy farms; those for mastitis detection and estrus detection were the most-used sensor systems. The use of sensor systems was different for farms using an automatic milking system (AMS) and a conventional milking system (CMS). Reasons for investing were different for different sensor systems. For sensor systems attached to the AMS, the farmers made no conscious decision to invest: they answered that the sensors were standard in the AMS or were bought for reduced cost with the AMS. The main reasons for investing in estrus detection sensor systems were improving detection rates, gaining insights into the fertility level of the herd, improving profitability of the farm, and reducing labor. Main reasons for not investing in sensor systems were economically related. It was very difficult to characterize farms with and without sensor systems. Farms with CMS and sensor systems had more cows than CMS farms without sensor systems. Furthermore, farms with sensor systems had fewer labor hours per cow compared with farms without sensor systems. Other farm characteristics (age of the farmer, availability of a successor, growth in herd size, milk production per cow, number of cows per hectare, and milk production per hectare) did not differ for farms with and without sensor systems. PMID:25465556

Steeneveld, W; Hogeveen, H

2015-01-01

133

Shape, size, strain and correlations in quantum dot systems studied by grazing incidence X-ray scattering methods  

E-print Network

Science S.A. All rights reserved. Keywords: X-ray scattering; Quantum dots; Semiconductor nanostructuresShape, size, strain and correlations in quantum dot systems studied by grazing incidence X heterostructures containing 3D islands (`quantum dots'). We show that the combination of the depth sensitivity

Ludwig-Maximilians-Universität, München

134

The effects of potential changes in United States beef production on global grazing systems and greenhouse gas emissions  

E-print Network

The effects of potential changes in United States beef production on global grazing systems and greenhouse gas emissions Jerome Dumortier1 , Dermot J Hayes2 , Miguel Carriquiry2 , Fengxia Dong3 , Xiaodong spillover effects on forestry and vice versa. Hence, the implementation of large-scale agricultural policies

Zhou, Yaoqi

135

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

136

Effect of Weaning System on Milk Composition and Distribution of Milk Fat within the Udder of East Friesian Dairy Ewes  

Microsoft Academic Search

We investigated whether the inhibition of milk ejec- tion during and\\/or between machine milkings is respon- sible for the low milk fat observed in commercial milk obtained from dairy ewes managed with a mixed system (MIX) of partial daily suckling (10 h) and once daily machine milking (after 14 h of udder filling). East Friesian crossbred dairy ewes were randomly

B. C. McKusick; D. L. Thomas; J. E. Romero; P. G. Marnet

2002-01-01

137

Sheep grazing to manage crop residues, insects and weeds in Northern Plains grain and alfalfa systems  

Technology Transfer Automated Retrieval System (TEKTRAN)

Sheep are traditionally produced on rangelands or pasture forages and supplemented during winter with harvested feeds. In recent years, sheep producers have made great strides using commercial-scale grazing on native rangelands to control noxious weeds and excess fire fuels. Incorporating grazing in...

138

Acoustic monitoring system to quantify ingestive behavior of free-grazing cattle  

Technology Transfer Automated Retrieval System (TEKTRAN)

Methods to estimate intake in grazing livestock include using markers, visual observation, mechanical sensors that respond to jaw movement and acoustic recording. In most of the acoustic monitoring studies, the microphone is inverted on the forehead of the grazing livestock and the skull is utilize...

139

Global Warming Potential of Long-Term Grazing Management Systems in the Northern Great Plains  

Technology Transfer Automated Retrieval System (TEKTRAN)

Grazing lands in the northern Great Plains of North America are extensive, occupying over 50 Mha. Yet grazing land contributions to, or mitigation of, global warming potential (GWP) is largely unknown for the region. The objective of this study was to estimate GWP for three long-term (70 to 90 yr)...

140

Temporary alterations to postpartum milking frequency affect whole-lactation milk production and the energy status of pasture-grazed dairy cows.  

PubMed

This study investigated the immediate and long-term effects of temporary alterations to postpartum milking frequency (MF) on milk production, body condition score (BCS), and indicators of energy status in pasture-grazed cows supplemented with concentrates. Multiparous Holstein-Friesian cows (n=150) were randomly assigned to 1 of 5 groups at calving: milked twice daily (2×) throughout lactation (control), or milked either once daily (1×) or 3 times daily (3×) for 3 or 6wk immediately postpartum, and then 2× for the remainder of lactation. During wk 1 to 3 postpartum, cows milked 1× produced 15% less milk and 17% less energy-corrected milk (ECM) than cows milked 2×. This immediate production loss increased to 20% less milk and 22% less ECM during wk 4 to 6 postpartum for cows that remained on 1× milking; these animals also produced less than 1× cows switched to 2× milking after 3wk. During wk 8 to 32, when all cows were milked 2×, those previously milked 1× had sustained reductions in milk (-6%) and ECM (-8%) yields, which were not affected by the duration of reduced postpartum MF. In contrast, cows milked 3× postpartum had 7% greater milk yields during wk 1 to 6 compared with 2× controls, irrespective of the duration of increased MF. Milk yields also remained numerically greater (+5%) during wk 8 to 32 in cows previously milked 3×. Nevertheless, yields of ECM were not increased by 3× milking, because of lower milk fat and protein contents that persisted for the rest of lactation. In addition, indicators of cow energy status reflected an increasing state of negative energy balance with increasing MF. Cows milked 1× postpartum had greater plasma glucose and lower plasma nonesterified fatty acid concentrations during the reduced MF, and plasma glucose remained lower for 2wk after cows had switched to 2× milking. Moreover, BCS was improved relative to 2× controls from wk 5 to 6. In contrast, cows milked 3× had lower plasma glucose concentrations, greater plasma nonesterified fatty acid concentrations, and greater BCS loss during wk 1 to 3; however, greater body fat mobilization was not sustained, indicating that additional energy supplements may be required to achieve better milk production responses. In conclusion, temporary 1× milking had lactation-long negative effects on milk and milk component yields but improved cow energy status and BCS, whereas temporary 3× milking immediately increased milk yield but did not improve milk fat and protein yields in pasture-grazed cows. PMID:25200777

Phyn, C V C; Kay, J K; Rius, A G; Morgan, S R; Roach, C G; Grala, T M; Roche, J R

2014-11-01

141

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. PMID:25049970

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

2014-01-01

142

Modification of digestive system microbiome of lactating dairy cows by feeding Bovamine: effect on ruminal fermentation  

Technology Transfer Automated Retrieval System (TEKTRAN)

We evaluated the immune modulatory effects as well as effects on productivity of Bovamine® (Lactobacillus acidophilus strain NP51 and Probionibacterium freudenreichii) on the digestive system microbiome of dairy cattle during late lactation (average DIM = 202). To unveil the underlying mechanisms, ...

143

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. PMID:23012457

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

2012-01-01

144

Effects of cattle grazing systems on shrub-grassland birds in south Texas  

E-print Network

of the vegetation by domestic grazers increases, a more even physiognomy is expected with less structural diversity, especially in the lower grass and forb components (Savory 1979). Grazing constitutes a This thesis follows the style and format of~h~gf ~il lif ~M...). As the intensity of grazing increases, there is a tendency for greater use of the available forage. Extended periods of intensive grazing are expected to result in a more uniform pattern of forage use with little variation in forage height (Savory 1979). At high...

Swanson, Douglas Wayne

1988-01-01

145

Measurement and mitigation of methane emissions from beef cattle in tropical grazing systems: a perspective from Australia and Brazil.  

PubMed

The growing global demand for food of animal origin will be the incentive for countries such as Australia and Brazil to increase their beef production and international exports. This increased supply of beef is expected to occur primarily through on-farm productivity increases. The strategies for reducing resultant greenhouse gas (GHG) emissions should be evaluated in the context of the production system and should encompass a broader analysis, which would include the emissions of methane (CH4) and nitrous oxide (N2O) and carbon sequestration. This paper provides an insight into CH4 measurement techniques applicable to grazing environments and proposed mitigation strategies, with relevance to the production systems that are predominant in grazing systems of Australia and Brazil. Research and technology investment in both Australia and Brazil is aimed at developing measurement techniques and increasing the efficiency of cattle production by improving herd genetics, utilization of the seasonal feed-base and reducing the proportion of metabolizable energy lost as CH4. Concerted efforts in these areas can be expected to reduce the number of unproductive animals, reduce age at slaughter and inevitably reduce emission intensity (EI) from beef production systems. Improving efficiency of livestock production systems in tropical grazing systems for Australia and Brazil will be based on cultivated and existing native pastures and the use of additives and by-products from other agricultural sectors. This approach spares grain-based feed reserves typically used for human consumption, but potentially incurs a heavier EI than current intensive feeding systems. The determination of GHG emissions and the value of mitigation outcomes for entire beef production systems in the extensive grazing systems is complex and require a multidisciplinary approach. It is fortunate that governments in both Australia and Brazil are supporting ongoing research activities. Nevertheless, to achieve an outcome that feeds a growing population while reducing emissions on a global scale continues to be a monumental challenge for ruminant nutritionists. PMID:23739477

Berndt, A; Tomkins, N W

2013-06-01

146

Interpreting Grazing Behavior  

E-print Network

Livestock producers can use their observations of grazing behavior to gauge the amount and quality of forage being consumed. This publication explains how grazing animals eat, when and where they graze, and how forage availability, patch grazing...

Lyons, Robert K.; Machen, Richard V.

2000-12-01

147

Design of optical systems of grazing incidence monochromators with concave grating  

NASA Astrophysics Data System (ADS)

The optical scheme of grazing incidence monochromator with concave grating with variable space is offered. The monochromator has a simplified kinematic scheme of spectrum scanning mechanism. Scanning is obtained by turning the exit slit and grating, fixed with each other relatively to the axis that goes through the vertex of the concave grating while enter slit is fixed. Kinematic scheme provides change of grazing incidence angle and constant grazing angle of diffraction. Moreover, increase of grazing incidence angle affects an increase of the wave length. In this case shorter wave length radiation diffracts on the grating with more losses. This results in decrease of the highest spectrum orders, being not preferable. The well-known schemes on the Rowland circle have an entrance slit with significant linear motion, which makes the construction more complicated. Those conditions for changing the incidence and diffraction angles are not accepted in monochromators of constant angle of deviation.

Savushkin, Alexander V.; Savushkin, Oleg A.

1998-11-01

148

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

149

Greenhouse gas emissions from simulated beef and dairy livestock systems in the United States  

Microsoft Academic Search

Computer spreadsheets were developed to evaluate greenhouse gas (GHG) emissions from U.S. beef and dairy livestock systems\\u000a from nine locations. Of the beef systems the cow-calf herd emitted the most and feedlot cattle the least methane (CH4) and nitrous oxide (N2O) per unit product. Carbon dioxide (CO2) emissions per unit product were the least for the cow-calf and greatest for

Hope W. Phetteplace; Donald E. Johnson; Andrew F. Seidl

2001-01-01

150

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

151

Amazing Grazing.  

ERIC Educational Resources Information Center

Countless acres of grasslands stretch across the American West. Centuries ago, bison roamed the range freely and lived off the grass. By the 19th century, herds of cattle grazed the same land. Over time, much of the original grassland was either plowed and planted or trampled to dust, causing the topsoil to dry up and blow away. Today many…

Peterson, Cris

152

A Life Cycle Assessment of integrated dairy farm-greenhouse systems in British Columbia.  

PubMed

The purpose of this study was to evaluate the anticipated environmental benefits from integrating a dairy farm and a greenhouse; the integration is based on anaerobic digestion of manures to produce biogas energy, biogenic CO2, and digested slurry. A full Life Cycle Assessment (LCA) has been conducted on six modeled cases applicable in British Columbia, to evaluate non-renewable energy consumption, climate change, acidification, eutrophication, respiratory effects and human toxicity. Compared to conventional practice, an integrated system has the potential to nearly halve eutrophication and respiratory effects caused by inorganic emissions and to reduce non-renewable energy consumption, climate change, and acidification by 65-90%, while respiratory effects caused by organic emissions become negative as co-products substitute for other materials. Co-digestion of other livestock manures, greenhouse plant waste, or food and food processing waste with dairy manure can further improve the performance of the integrated system. PMID:24138886

Zhang, Siduo; Bi, Xiaotao Tony; Clift, Roland

2013-12-01

153

Performance of a two-phase anaerobic digestion system when treating dairy wastewater  

Microsoft Academic Search

Performance of a laboratory-scale two-phase anaerobic digestion system treating dairy wastewater was investigated using the pre-determined operating criteria for the anaerobic acidification reactor. The results, obtained from a 9month operation, showed that overall, 90% COD and 95% BOD removal efficiencies at an organic loading rate (OLR) of 5kg COD\\/m3d and a hydraulic retention time (HRT) of 2days were achieved. The

O. Ince

1998-01-01

154

your dairy goatyour dairy goatyour dairy goatyour dairy goatyour dairy goat The Modern Dairy GoatThe Modern Dairy GoatThe Modern Dairy GoatThe Modern Dairy GoatThe Modern Dairy Goat  

E-print Network

your dairy goatyour dairy goatyour dairy goatyour dairy goatyour dairy goat The Modern Dairy GoatThe Modern Dairy GoatThe Modern Dairy GoatThe Modern Dairy GoatThe Modern Dairy Goat The modern dairy goat-quality feed, and should be milked properly. With the exception of bucks during breeding season, goats do

New Hampshire, University of

155

The effect of grazing management systems on performance of beef animals and on the yield and chemical and botanical composition of Texas coast prairie pastures  

E-print Network

grass pasture at a moderate level of production was only slightly more efficient when daily strip grazing was employed than when a conventional rotation soheme was used. Cows were moved in the rotation scheme approximately every 5 or 6 days... in the grass and clover from Dallisgrass - white clover pastures, Angleton, Texas~ from April 4. to July' 4~ 1957 14. The influence of grazing management systems on the weighted average protein content of DalH. sgrass white clover forage at the beginning...

Riewe, Marvin Edmund

2012-06-07

156

DairyGHG: a tool for evaluating the greenhouse gas emissions and carbon footprint of dairy production systems  

Technology Transfer Automated Retrieval System (TEKTRAN)

Greenhouse gas (GHG) emissions and their potential impact on the environment have become important national and international concerns. Dairy production, along with all other animal agriculture, is a recognized source of GHG emissions, but little information exists on the net emissions from our farm...

157

[Grazing systems, rotenone and parasites control in crossbred calves: effect on live weight gain and on parasites burdens].  

PubMed

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 evaluated. Rotenone showed acaricide action on larvae and engorged ticks during in vitro tests and on larvae in experimentally infected calves. Three treatments with endectocide decreased (P < .05) the number of EPG and ticks and increased (P < .05) the weight gain in the dry season. Animals treated with only one application of levamisole showed EPG intermediate and different (P < .05) from the groups treated with endectocide (lower) and control (higher) in the dry season, but the weight gain obtained with this treatment did not differ from the control group. During the raining season the animals treated with fipronil were significantly less parasited by horn fly, tick and larvae of Dermatobia hominis and the group treated with rotenone were significantly less parasited by horn fly in relation to control. Animals under rotational grazing showed significantly higher EPG than those under continuous grazing. Three treatments with endectocide in the dry season plus three acaricide treatments with fipronil in the raining season reduced EPG, tick, and screw worm larva counts, and provided a significant increase (23 kg) of live weight gain in relation to untreated animals. PMID:20040207

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

2009-01-01

158

Short communication: a food-systems approach to assessing dairy product waste.  

PubMed

Concern about world population increase, food security, and the environmental burdens of food production have made food-waste reduction a social and environmental priority. In this context, the quantification of dairy product waste is especially difficult due to the varied means of disposal, by solid and liquid waste streams, and due to inclusion as an ingredient in many processed foods. In this study, food intake data from the Australian National Nutrition Survey (>13,000 participants; >4,500 food items) were disaggregated into basic foods and total national dairy product intake was expressed in whole-milk equivalents. This result was compared with total domestic milk supply, indicating a level of waste of 29% for dairy products in the Australian food system. With national food-waste reduction targets becoming increasingly common, reliable estimates of food waste at the national scale are important for goal setting, baseline reporting, and performance monitoring. For this purpose, the systems approach to assessing food waste demonstrated in this project is deemed to have advantages over other common methods of food-waste assessment, such as bin audits, waste diaries, and surveys. PMID:25064645

Ridoutt, B G; Baird, D L; Bastiaans, K; Darnell, R; Hendrie, G A; Riley, M; Sanguansri, P; Syrette, J; Noakes, M; Keating, B A

2014-10-01

159

PROFITABILITY OF PRODUCTION SYSTEMS WITH COTTON AND PEANUTS INCORPORATING WINTER ANNUAL GRAZING  

Technology Transfer Automated Retrieval System (TEKTRAN)

The use of contracts in livestock production has been widespread since at least the 1950s. Under grazing contracts, cattle owners usually place stocker cattle on pasture, owned or leased by a caretaker (e.g. farmer or landowner). These contacts provide farmers an increase in revenue by utilizing win...

160

Response of a Depleted Sagebrush Steppe Riparian System to Grazing Control and Woody Plantings  

E-print Network

Nebraska, an M.S. degree in range management, and a Ph.D. degree in botany (plant ecology) from Colorado State University. He joined the Forest Service in 1960 and conducted research on rangelands in Arizona, Louisiana, and Utah. More recently he has focused on riparianlivestock grazing issues in ldaho and adjacent States. Nancy L. Shaw is a Botanist with the lntermountain

Forest Service; Warren P. Clary; Nancy L. Shaw; Jonathan G. Dudley; Victoria A. Saab; John W. Kinney; Lynda C. Smithman

161

LARGE SCALE GRAZING SYSTEMS IN THE NORDIC REGION: THEIR HISTORY, CHARACTERISTICS AND STABILITY  

E-print Network

, the Fennoscandian Mountains were primarily grazed by wild reindeer, which were hunted by the Sámi in northern herds of domesticated reindeer, which were used for pulling sledges, carrying packs, milking and as attraction animals in wild reindeer hunts. To have larger herds had been impossible, since reindeer do

Oksanen, Lauri

162

CATTLE GRAZING EFFECTS ON DRYLAND CROPPING SYSTEM PRODUCTIVITY AND SOIL PROPERTIES  

Technology Transfer Automated Retrieval System (TEKTRAN)

On the southern Great Plains, dryland wheat (Triticum aestivum L.) and grain sorghum [Sorghum bicolor (L.) Moench] are grown in a wheat-sorghum-fallow (WSF) rotation that consistently produces two crops in a three year cycle using precipitation stored in the soil. Integration of cattle grazing on wh...

163

Non-traditional forages in a Managed Grazing System for Control of Gastrointestinal Parasites in Sheep  

Technology Transfer Automated Retrieval System (TEKTRAN)

This project compared forage chicory with brown mid-rib sorghum x sudangrass (BMR) to determine if anti-parasitic effects of chicory could be demonstrated. We evaluated changes in fecal egg counts in two groups of lambs before and after grazing these forages for periods of two to three weeks. Body...

164

MODELING THE POTENTIAL SPATIAL DISTRIBUTION OF BEEF CATTLE GRAZING USING A GEOGRAPHIC INFORMATION SYSTEM  

EPA Science Inventory

Data regarding grazing utilization in the western United States are typically compiled within administrative boundaries(e.g. allotment,pasture). For large areas, an assumption of uniform distribution is seldom valid. Previous studies show that vegetation type, degree of slope, an...

165

Soil quality parameters for row-crop and grazed pasture systems with agroforestry buffers  

Technology Transfer Automated Retrieval System (TEKTRAN)

Incorporation of trees and establishment of buffers are practices that can improve soil quality. Soil enzyme activities and water stable aggregates are sensitive indices for assessing soil quality by detecting early changes in soil management. However, studies comparing grazed pasture and row crop...

166

Co-treatment of domestic and dairy wastewater in an activated sludge system.  

PubMed

This research assesses the potential for co-treatment of a dairy wastewater with a domestic wastewater in a lab-scale, continuous-flow, activated sludge system. To evaluate the influence of the dairy waste contribution, seven runs were conducted with each run being a mixture of dairy wastewater (either cheese or milk) in different ratios ranging from 1:0.01 to 1:0.30 by volume. More than 87% of the carbon was removed for both waste additions; however, while 95% ammonia-nitrogen removal was recorded for the cheese waste, only 75% removal was obtained for the milk. Kinetic studies for carbon consumption revealed a first-order model with lower kinetic constants as the cheese waste proportion increased. Specific carbon consumption rates indicated that the biomass had not reached its maximum potential to degrade carbon. The ability of the biomass to settle was hindered when the Gram negative to Gram positive filamentous bacteria ratio increased to approximately 1.5. PMID:25204524

Sparchez, E; Elefsiniotis, P; Wareham, D G; Fongsatitkul, P

2015-03-01

167

Feeding Waste Milk to Dairy Calves  

E-print Network

with calves fed nonpasteurized milk. The researchers calculated that 315 calves (from a dairy of approximately 1,260 cows) need to be fed daily to make pasteurization economically feasible. *Respectively, Extension Dairy Specialist, The Texas A&M University... System; Extension Dairy Specialist, New Mexico State University; Extension Dairy Specialist, Oklahoma State University; Extension Dairy Specialist, The Texas A&M University System Research from the National Animal Disease Center showed that pasteurization...

Stokes, Sandra R.; Looper, Mike; Waldner, Dan; Jordan, Ellen R.

2002-02-14

168

Methane emission from dairy cows and wether sheep fed subtropical grass?dominant pastures in midsummer in New Zealand  

Microsoft Academic Search

Methane emission was measured from 10 dairy cows and 12 wether sheep grazing kikuyu grass? (Pennisetum clandestinum) dominant pastures at Waimate North, Northland, in February 1997 and March 1999, and from 10 dairy cows grazing summer grass? (Digitaria sanguinalis) dominant pasture at Edgecumbe, Bay of Plenty, in March 2000. Methane emission was measured from each animal for 5 consecutive days

M. J. Ulyatt; K. R. Lassey; I. D. Shelton; C. F. Walker

2002-01-01

169

Locoweed grazing.  

PubMed

Locoweed is the most widespread poisonous plant problem in the western U. S. Eleven species of Astragalus and Oxytropis (and many varieties within these species) cause locoism. Many locoweed species are endemic and are restricted to a narrow niche or habitat. Other locoweed species experience extreme population cycles; the population explodes in wet years and dies off in drought. A few species, such as O. sericea, are relatively stable and cause persistent poisoning problems. Knowledge of where locoweeds grow and the environmental conditions when they become a threat is important to manage livestock and avoid poisoning. Locoweeds are relatively palatable. Many locoweeds are the first plants to begin growth in the spring and regrow in the fall. Livestock generally prefer the green-growing locoweeds to other forage that is dormant in the late fall, winter, and spring. The most effective management strategy is to deny livestock access to locoweeds during critical periods when they are more palatable than the associated forage. Herbicides can control existing locoweed populations and provide "safe" pastures for critical periods. However, locoweed seed in soil will germinate and re-establish when environmental condition are favorable. Good range management and wise grazing strategies can provide adequate forage for livestock and prevent them from grazing locoweed during non-critical periods of the year when it is relatively less palatable than associated forages. PMID:10091127

Ralphs, M H; James, L F

1999-02-01

170

Agreement between bovine respiratory disease scoring systems for pre-weaned dairy calves.  

PubMed

Clinical scoring systems have been proposed for respiratory disease diagnosis in calves, including the Wisconsin (WI) system (McGuirk in 2008) which uses five clinical signs, each partitioned into four levels of severity. Recently, we developed the California (CA) bovine respiratory disease (BRD) scoring system requiring less calf handling and consisting of six clinical signs, each classified as normal or abnormal. The objective of this study was to estimate the on-farm agreement between the WI and the CA scoring systems. A total of 100 calves were enrolled on a CA dairy and assessed for BRD case status using the two scoring systems simultaneously. The Kappa coefficient of agreement between these two systems was estimated to be 0.85, which indicated excellent agreement beyond chance. The simpler design and reduced calf handling required by the CA BRD scoring system may make it advantageous for on-farm use. PMID:25424381

Aly, Sharif S; Love, William J; Williams, Deniece R; Lehenbauer, Terry W; Van Eenennaam, Alison; Drake, Christiana; Kass, Philip H; Farver, Thomas B

2014-12-01

171

Ammonia losses from urine and dung of grazing cattle. effect of N intake  

NASA Astrophysics Data System (ADS)

Nitrogen excretion by cattle during grazing is a significant source of atmospheric ammonia. In this study the relation between NH 3 volatilization and N intake was investigated in wind tunnel experiments with simulated urine patches and dung pats. Excreta were collected from four groups of dairy cattle grazing continuously on either ryegrass fertilized with 300 kg N ha -1 or unfertilized white clover-ryegrass. The two groups of cattle in each grazing system received either 139 or 304 g N cow -1 d -1 in concentrates, corresponding to average total N intakes in the range of 500-700 g N cow -1 d -1. Ammonia losses from dung were insignificant, while total losses from urine, which were estimated by curve-fitting, ranged from 3 to 52% of urinary N. Urea-N in the urine applied in the experiments constituted, with one exception, 64-94% of urinary N. The fraction of urea-N increased significantly with total N concentration in subsamples from individual animals. In the soil, hydrolysis of urea to NH 3 was almost complete within 24 h, and release of NH 3 was indicated by scorching. Milk yield and the production of milk protein was not related to N intake or grazing system, while estimated NH 3 losses were significantly reduced at the lower N intake level within the range of N intakes obtained.

Petersen, Søren O.; Sommer, Sven G.; Aaes, Ole; Søegaard, Karen

172

The effect of changing cow production and fitness traits on net income and greenhouse gas emissions from Australian dairy systems.  

PubMed

The aim of this study was to compare the effect of changing a range of biological traits on farm net income and greenhouse gas emissions (expressed in carbon dioxide equivalents, CO2-eq.) in the Australian dairy cow population. An average cow was modeled, using breed-average information for Holsteins and Jerseys from the Australian Dairy Herd Improvement Scheme. A Markov chain approach was used to describe the steady-state herd structure, as well as estimate the CO2-eq. emissions per cow and per kilogram of milk solids. The effects of a single unit change in herd milk volume, fat and protein yields, live weight, survival, dry matter intake, somatic cell count, and calving interval were assessed. With the traits studied, the only single-unit change that would bring about a desirable increase in both net income and reduced emissions intensity per cow and per kilogram of milk solids in Australian dairy herds would be an increase in survival and reductions in milk volume, live weight, DMI, SCC, and calving interval. The models developed can be used to assess lifetime dairy system abatement options by breeding, feeding, and management. Selective breeding and appropriate management can both improve health, fertility, and feed utilization of Australian dairy systems and reduce its environmental impact. PMID:24140333

Bell, M J; Eckard, R J; Haile-Mariam, M; Pryce, J E

2013-12-01

173

Ecology of grazing lawns in Africa.  

PubMed

Grazing lawns are a distinct grassland community type, characterised by short-stature and with their persistence and spread promoted by grazing. In Africa, they reveal a long co-evolutionary history of grasses and large mammal grazers. The attractiveness to grazers of a low-biomass sward lies in the relatively high quality of forage, largely due to the low proportion of stem material in the sward; this encourages repeat grazing that concomitantly suppresses tall-grass growth forms that would otherwise outcompete lawn species for light. Regular grazing that prevents shading and maintains sward quality is thus the cornerstone of grazing lawn dynamics. The strong interplay between abiotic conditions and disturbance factors, which are central to grazing lawn existence, can also cause these systems to be highly dynamic. Here we identify differences in growth form among grazing lawn grass species, and assess how compositional differences among lawn types, as well as environmental variables, influence their maintenance requirements (i.e. grazing frequency) and vulnerability to degradation. We also make a clear distinction between the processes of lawn establishment and lawn maintenance. Rainfall, soil nutrient status, grazer community composition and fire regime have strong and interactive influences on both processes. However, factors that concentrate grazing pressure (e.g. nutrient hotspots and sodic sites) have more bearing on where lawns establish. Similarly, we discuss the relevance of enhanced rates of nitrogen cycling and of sodium levels to lawn maintenance. Grazer community composition and density has considerable significance to grazing lawn dynamics; not all grazers are adapted to foraging on short-grass swards, and differences in body size and relative mouth dimensions determine which species are able to convert tall-grass swards into grazing lawns under different conditions. Hence, we evaluate the roles of different grazers in lawn dynamics, as well as the benefits that grazer populations derive from having access to grazing lawns. The effects of grazing lawns can extend well beyond their borders, due to their influence on grazer densities, behaviour and movements as well as fire spread, intensity and frequency. Variation in the area and proportion of a landscape that is grazing lawn can thus have a profound impact on system dynamics. We provide a conceptual model that summarises grazing lawn dynamics, and identify a rainfall range where we predict grazing lawns to be most prevalent. We also examine the biodiversity associated with grazing lawn systems, and consider their functional contribution to the conservation of this biodiversity. Finally, we assess the utility of grazing lawns as a resource in a rangeland context. PMID:25231416

Hempson, Gareth P; Archibald, Sally; Bond, William J; Ellis, Roger P; Grant, Cornelia C; Kruger, Fred J; Kruger, Laurence M; Moxley, Courtney; Owen-Smith, Norman; Peel, Mike J S; Smit, Izak P J; Vickers, Karen J

2014-09-18

174

Factors affecting animal performance during the grazing season in a mountain cattle production system.  

PubMed

The factors influencing weight changes during the grazing season of Brown Swiss autumn-calving cows and Brown Swiss and Pirenaica spring-calving cows and their calves were studied over an 8-yr period in Spanish mountain conditions. The data set comprised 552 annual production cycles of cows that calved in two consecutive years. The animals grazed on alpine ranges during the summer and on forest pastures in the spring and autumn. They were housed during the winter and fed at different feeding levels (83 to 117% of their energy requirements) throughout the years of study. Weights were recorded every 3 mo and corrected to account for changes of digestive content and fetal growth, using theoretical relationships. Cow weight gains both on forest pastures and high mountain ranges were higher in autumn- than in spring-calving Brown Swiss cows, and therefore also during the whole grazing season (52.1 vs 7.7 kg, respectively, P < 0.001). Therefore, weight at calving and thereafter was significantly higher in autumn- than in spring-calving cows, which was associated with better reproductive performance (35.5 vs 49.1 d from calving to first ovulation, P < 0.01). In the spring-calving herd, Pirenaica cows had slightly higher gains than Brown Swiss cows during the grazing period (18.5 vs 7.7 kg, P < 0.001), mainly due to their higher gains on forest pastures, but their reproductive performance was similar (44.5 vs 49.1 d from calving to first ovulation, respectively, not statistically significant). Gains were higher in multiparous than in primiparous cows (31.1 vs 14.1 kg, respectively, P < 0.001), especially in the case of Brown Swiss cows, which were younger at first calving. Gains were affected by year of study (P < 0.001) and previous weight changes during the housing period (r = -0.35 and r = -0.21 in autumn- and spring-calving cows respectively, P < 0.001). In the case of autumn-calving cows, performance on pasture was also affected by the stage of pregnancy at housing (r = -0.51, P < 0.001). Growth rates through lactation were higher in autumn- than in spring-born calves (P < 0.001), although the shorter lactation period resulted in lower weight at weaning of the former (P < 0.001). Breed was a significant source of variation in the performance of spring-born calves, weights and gains being higher in Brown Swiss than in Pirenaica calves (P < 0.001). PMID:12078746

Casasús, I; Sanz, A; Villalba, D; Ferrer, R; Revilla, R

2002-06-01

175

Rotational grazing on rangelands: Reconciliation of perception and experimental evidence  

Technology Transfer Automated Retrieval System (TEKTRAN)

The experimental evaluation of grazing systems represents a highly visible and lengthy chapter in the history of the rangeland profession. Although experimentation has largely concluded, contrasting interpretations still remain regarding the potential benefits of rotational grazing systems on rangel...

176

Field Demonstration of the Performance of a Geotube® Dewatering System to Reduce Phosphorus and Other Substances from Dairy Lagoon Effluent  

E-print Network

of this dewatering system was furnished by the technology provider. Cost estimates for a long-term dewatering system were $90,000 to treat 1.9 million gallons of dairy lagoon effluent containing 15+ years worth of nutrients and solids that settled to the bottom...

Mukhtar, Saqib; Wagner, Kevin; Gregory, Lucas

177

Microbial transport from dairying under two spray-irrigation systems in Canterbury, New Zealand.  

PubMed

Transport through the soil and vadose zone to groundwater of Escherichia coli, fecal coliforms, and Campylobacter spp. from pasturing of dairy cows was studied on two working dairy farms under a traveling irrigator and a center pivot system. Leachate was collected from 1.5 m depth using a large linear lysimeter over a period of 4 yr after rainfall or irrigation applied using a traveling irrigator. There was little transport of fecal coliforms or Campylobacter from irrigation applications of 55 mm. There was some transport of fecal coliforms at applications of 80 mm (corresponding to irrigation plus heavy rainfall) but no detectable Campylobacter. When fresh cow pats were placed on half of the lysimeter plots with an 80-mm water application, there was transport of fecal coliforms and Campylobacter, but levels of Campylobacter were low (or=1 cfu 100 mL(-1). Campylobacter was detected in 0.7% of samples over the study period, with equal percentages from up- and downgradient wells. The results indicate minimal impact of dairying at these sites on microbial quality of groundwater as a result of spray irrigation using traveling irrigators at rates of approximately 55 mm every 2 wk or center pivot irrigators at 18 mm every 3 to 4 d. PMID:20400578

Close, Murray; Noonan, Mike; Hector, Ross; Bright, John

2010-01-01

178

The effects of potential changes in United States beef production on global grazing systems and greenhouse gas emissions  

NASA Astrophysics Data System (ADS)

We couple a global agricultural production and trade model with a greenhouse gas model to assess leakage associated with modified beef production in the United States. The effects on emissions from agricultural production (i.e., methane and nitrous oxide emissions from livestock and crop management) as well as from land-use change, especially grazing system, are assessed. We find that a reduction of US beef production induces net carbon emissions from global land-use change ranging from 37 to 85 kg CO2-equivalent per kg of beef annualized over 20 years. The increase in emissions is caused by an inelastic domestic demand as well as more land-intensive cattle production systems internationally. Changes in livestock production systems such as increasing stocking rate could partially offset emission increases from pasture expansion. In addition, net emissions from enteric fermentation increase because methane emissions per kilogram of beef tend to be higher globally.

Dumortier, Jerome; Hayes, Dermot J.; Carriquiry, Miguel; Dong, Fengxia; Du, Xiaodong; Elobeid, Amani; Fabiosa, Jacinto F.; Martin, Pamela A.; Mulik, Kranti

2012-06-01

179

Body condition score at calving affects systemic and hepatic transcriptome indicators of inflammation and nutrient metabolism in grazing dairy cows.  

PubMed

Calving body condition score (BCS) is an important determinant of early-lactation dry matter intake, milk yield, and disease incidence. The current study investigated the metabolic and molecular changes induced by the change in BCS. A group of cows of mixed age and breed were managed from the second half of the previous lactation to achieve mean group BCS (10-point scale) that were high (HBCS, 5.5; n=20), medium (MBCS, 4.5; n=18), or low (LBCS, 3.5; n=19). Blood was sampled at wk -4, -3, -2, 1, 3, 5, and 6 relative to parturition to measure biomarkers of energy balance, inflammation, and liver function. Liver was biopsied on wk 1, 3, and 5 relative to parturition, and 10 cows per BCS group were used for transcript profiling via quantitative PCR. Cows in HBCS and MBCS produced more milk and had greater concentrations of nonesterified fatty acids and ?-hydroxybutyrate postpartum than LBCS. Peak concentrations of nonesterified fatty acids and ?-hydroxybutyrate and greater hepatic triacylglycerol concentrations were recorded in HBCS at wk 3. Consistent with blood biomarkers, HBCS and MBCS had greater expression of genes associated with fatty acid oxidation (CPT1A, ACOX1), ketogenesis (HMGCS2), and hepatokines (FGF21, ANGPTL4), whereas HBCS had the lowest expression of APOB (lipoprotein transport). Greater expression during early lactation of BBOX1 in MBCS and LBCS suggested greater de novo carnitine synthesis. The greater BCS was associated with lower expression of growth hormone/insulin-like growth factor-1 signaling axis genes (GHR1A, IGF1, and IGFALS) and greater expression of gluconeogenic genes. These likely contributed to the higher milk production and greater gluconeogenesis. Despite greater serum haptoglobin around calving, cows in HBCS and MBCS had greater blood albumin. Cows in MBCS, however, had a higher albumin:globulin ratio, probably indicating a less pronounced inflammatory status and better liver function. The marked decrease in expression of NFKB1, STAT3, HP, and SAA3 coupled with the increase in ALB on wk 3 in MBCS cows were consistent with blood measures. Overall, results suggest that the greater milk production of cows with higher calving BCS is associated with a proinflammatory response without negatively affecting expression of genes related to metabolism and the growth hormone/insulin-like growth factor-1 axis. Results highlight the sensitivity of indicators of metabolic health and inflammatory state to subtle changes in calving BCS and, collectively, indicate a suboptimal health status in cows calving at either BCS 3.5 or 5.5 relative to BCS 4.5. PMID:25497809

Akbar, H; Grala, T M; Vailati Riboni, M; Cardoso, F C; Verkerk, G; McGowan, J; Macdonald, K; Webster, J; Schutz, K; Meier, S; Matthews, L; Roche, J R; Loor, J J

2015-02-01

180

Ultraviolet Spectra of Star-Grazing Comets in the 49 Ceti Disk System  

NASA Astrophysics Data System (ADS)

49 Ceti is a young star that hosts a debris disk with an unusually large amount of carbon monoxide gas. This excess gas has been attributed to frequent collisions of comets within the disk. (Zuckerman & Song, 2012). Since 49 Ceti disk is nearly edge-on to our line of sight, it is a prime target to observe disk gas and evaporated material from star-grazing comets using absorption spectroscopy, as shown by detection of time-variable circumstellar absorption in optical spectra of the star (Montgomery & Welsh 2012). Here we discuss ultraviolet spectra of 49 Ceti taken using the Hubble Space Telescope Space Telescope Imaging Spectrograph (STIS) during two separate visits six days apart. The spectra show time-variable and highly Doppler shifted absorption features from ionized gaseous species. The maximum velocity of the time-variable gas corresponds to a minimum distance from the star of 0.06 AU. These features very likely come from star-grazing comets. Lower limits on element abundances in the gas were found using the apparent optical depth method. The variable comet gas appears carbon rich, despite the disk gas as a whole showing strong absorption features from both carbon and oxygen (Roberge et al., 2014, in press).

Miles, Brittany E.; Roberge, Aki; Welsh, Barry

2015-01-01

181

Ruminant Nutrition Symposium: a systems approach to integrating genetics, nutrition, and metabolic efficiency in dairy cattle.  

PubMed

The role of the dairy cow is to help provide high-quality protein and other nutrients for humans. We must select and manage cows with the goal of reaching the greatest possible efficiency for any given environment. We have increased efficiency tremendously over the years, yet the variation in productive and reproductive efficiency among animals is still quite large. In part this is because of a lack of full integration of genetic, nutritional, and reproductive biology into management decisions. However, integration across these disciplines is increasing as biological research findings show more specific control points at which genetics, nutrition, and reproduction interact. An ordered systems biology approach that focuses on why and how cells regulate energy and N use and on how and why organs interact by endocrine and neurocrine mechanisms will speed improvements in efficiency. More sophisticated dairy managers will demand better information to improve the efficiency of their animals. Using genetic improvement and proper animal management to improve milk productive and reproductive efficiency requires a deeper understanding of metabolic processes during the transition period. Using existing metabolic models, we can design experiments specifically to integrate new data from transcriptional arrays into models that describe nutrient use in farm animals. A systems modeling approach can help focus our research to make faster and large advances in efficiency and show directly how this can be applied on the farms. PMID:22021807

McNamara, J P

2012-06-01

182

Dairy Goat Day 2003Dairy Goat Day 2003Dairy Goat Day 2003Dairy Goat Day 2003 Sponsored by  

E-print Network

Dairy Goat Day 2003Dairy Goat Day 2003Dairy Goat Day 2003Dairy Goat Day 2003 Sponsored by University of California Dairy Goat Day 2003Dairy Goat Day 2003Dairy Goat Day 2003Dairy Goat Day 2003 And" Davis, CA 1918 University of California Dairy Goat Day 2003Dairy Goat Day 2003Dairy Goat Day 2003Dairy

Schladow, S. Geoffrey

183

Livestock Grazing and Wildlife: Developing Compatibilities  

Microsoft Academic Search

Abstract Livestock grazing has been considered detrimental to wildlife habitat. Managed gazing programs, however, have the potential to maintain habitat diversity and quality. In cases in which single-species management,predominates (sage-grouse [Centrocercus urophasianus] or elk [Cervus elaphus nelsoni] winter range), grazing systems specific to species' needs can be jmplemented. Managed livestock grazing can have 4 general impacts on vegetation: 1) alter

Martin Vavra

2005-01-01

184

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

185

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

186

Milk composition and flavor under different feeding systems: a survey of dairy farms.  

PubMed

Understanding the influence of regional dietary factors on the flavors of milk and dairy products will provide consumers with more options and promote the conservation of regional resources and the original terroir. The objective of this study was to evaluate the influence of regional differences in feeding systems on the composition, fatty acid content, and flavor of pasteurized milk at the farm level. Nine dairy farms using grass silage (GS), 6 farms using maize silage (MS), and 4 farms using by-products (BP) as the characteristic feed components were chosen for this survey. Fresh milk was sampled once per month from September 2008 to February 2009 at each dairy farm. The percentages of GS, MS, and BP (soybean curd residue or brewer's grain) in the feed were 32.4, 22.1, and 15.1%, respectively. The milk fat, protein, and lactose contents did not differ among the milks from farms with different feeding systems. Fatty acids with chain lengths of less than C16 and saturated fatty acids were present at higher concentrations in the milks from the GS and MS farms than in the milk from the BP farms; conversely, fatty acids with chain lengths greater than C18 and unsaturated fatty acids (UFA), including mono- (MUFA) and polyunsaturated fatty acids (PUFA), were present at higher concentrations in the milks from the BP farms than in the milks from the GS farms. No significant differences were detected in milk flavor, evaluated as sweetness, body, texture, aftertaste, and palatability, between the milks from the farms with different feeding systems. The proportion of BP in the cow's diet was positively correlated with the concentrations of fatty acids with chain lengths greater than C18 and with UFA, MUFA, and PUFA. In contrast, the proportion of GS in the diet was positively associated with the levels of milk fat, protein, fatty acids with chain lengths less than C16, and SFA. The MUFA, PUFA, UFA, and fatty acids with chain lengths greater than C18 were not associated with any of the milk flavors. These results suggest the regional differences in feeding systems contribute to the differences in the fatty acid compositions of milk at the farm level. However, these differences do not influence the flavor of pasteurized milk. Thus, more specific feed profiles will be required to provide a specific regional flavor to pasteurized milk. PMID:23769370

Yayota, M; Tsukamoto, M; Yamada, Y; Ohtani, S

2013-08-01

187

Design of a covered lagoon methane recovery system for a flush dairy  

SciTech Connect

A lagoon-type methane recovery system was designed for the Cal Poly Dairy, which milks 130 cows with a total population of 296 animals. Most of the herd is housed in freestall barns where the manure is deposited on concrete and flushed with fresh or recycled water to an existing lagoon with a volume of 19,300 cubic meters. The design includes a new, primary covered lagoon of 17,000 cubic meters volume. The floating cover will be made of very low density polyethylene (VLDPE), with an area of 4,500 square meters. The predicted output of the lagoon is an average of over 310 cubic meters of biogas per day containing 60 percent methane. The methane production from the covered lagoon is adequate to produce 18 to 24 kW on a continuous basis from the present cow population. In order to account for future herd size increases, a 40 kW engine generator was specified to operate in parallel with the utility system at a varying level of output controlled by the biogas supply. The non-economic benefits of this covered lagoon include the demonstration of its operation to the students and visitors at Cal Poly which in turn will serve the California Dairy Community. Odor control is the most important non-economic benefit. Conversion of volatile solids to biogas and recovery and use of the biogas limits odor to surrounding areas. The economic benefits of the methane recovery system include the approximately 160,000 kWh of electricity produced annually, worth almost $13,000. Financial analyses for the project showed a payback of 13.7 years with a 4% internal rate of return.

Williams, D.W. [ICF, Inc., Universal City, CA (United States); Moser, M. [Resource Conservation Management, Inc., Berkeley, CA (United States); Smith, J. [BioResource and Ag. Engineering Dept., San Luis Obispo, CA (United States)

1996-12-31

188

Grazing dynamics of cattle under heavily stocked continuous and short-duration grazing  

E-print Network

of defoliation, evidence is contradictory as to whether continuous grazing at proper stocking levels differs greatly from desirable patterns of defoliation. Still less is known about the effect of grazing systems on animal behavior and nutrition. Savory... at twice the recommended rate without depressing animal performance or damaging the forage resource (Savory 1978). Both grazing systems were stocked at about 1. 5 times the recommended number of animal-units (AU) in order to test this claim...

Grose, Paul Stephen

1983-01-01

189

Use of COSREEL, a computerised recording system, for herd health management of two dairy herds.  

PubMed

COSREEL, a computerised animal health recording system, has been used since October 1980 by two agricultural colleges for the management of their dairy herds. Each college and the veterinary practice which served the college has had its own typewriter terminal connected to a remote computer. Management and milk data have been coded and entered at the college and clinical data at the veterinary practice. An average of just over one management and veterinary event per week has been coded for every three cows in milk. Error rates were on average 11 per cent by one pair of users and 4 per cent by the other pair. COSREEL has provided a valuable aid to the management of the health of the two herds, and the regular use of pregnancy diagnosis, infertility investigation and oestrus detection action lists resulted in a considerable improvement in herd fertility at the two colleges. PMID:6688900

Lucey, S; Rowlands, G J; Russell, A M; Foster, S R; Wicks, B T; Parsons, S T; Stimpson, P M

1983-09-24

190

MEASURING INVERTEBRATE GRAZING ON SEAGRASSES AND EPIPHYTES  

EPA Science Inventory

The chapter describes methods to assess grazing rates, grazer preferences, and grazer impacts, by mobile organisms living in the canopy or in the rhizome layer in any seagrass system. One set of methods quantifies grazing activity in small to medium sized, mobile organisms livin...

191

Software for evaluating greenhouse gas emissions and the carbon footprint of dairy production systems  

Technology Transfer Automated Retrieval System (TEKTRAN)

Abstract: Dairy production, along with all other types of animal agriculture, is a recognized source of greenhouse gas (GHG) emissions, but little information exists on the net emissions from our farms. Component models for representing all important sources and sinks of CH4, N2O, and CO2 in dairy p...

192

Creating a System for Meeting the Fiber Requirements of Dairy Cows  

Microsoft Academic Search

Current NRC recommendations for dairy cattle provide limited guidance to nutritionists for meeting the fiber and carbohydrate needs of lactating cows. The NRC provides only minimum recommendations for fiber and no accommodation for factors such as physical effectiveness of fiber, interactions with non- fibrous carbohydrates, or animal attributes, which can affect the optimality of dairy rations. To be an im-

D. R. Mertens

1997-01-01

193

Systemic granulomatous disease in Brazilian cattle grazing pasture containing vetch (Vicia spp).  

PubMed

Vetch associated disease (hairy vetch poisoning) was observed in 8 herds of dairy cows in the state of Rio Grande do Sul, southern Brazil. In the pasture where 4 of these 8 herds were, Vicia villosa was the only vetch species represented, while cattle in the remaining 4 herds had access to both V villosa and V sativa but with large predominance of the former. Observed clinical signs included fever, dramatic drop in milk yield, thickening and wrinkling of the skin with multifocal plaques of alopecia, pruritus, conjunctivitis, nasal and ocular serous discharge, loss of weight and diarrhea. The mean morbidity in the 8 affected herds, representing 219 cattle, was 11.1% and the mortality was 100%. The duration of the clinical disease varied from 10 to 30 d. Gross lesions consisted of multifocal to coalescing grey-white soft to moderately firm nodules which infiltrated several organs, but were particularly prominent in lymph nodes, adrenal, renal cortex, spleen, liver, and myocardium. Microscopically the lesions consisted of extensive cellular infiltration composed of variable proportions of epithelioid macrophages, lymphocytes, plasma cells, and multinucleated giant cells; variable numbers of eosinophils were present in the inflammatory foci of several organs, but they were more prominent in the myocardium. PMID:15080204

Fighera, Rafael A; Barros, Claudio S L

2004-04-01

194

Future consequences and challenges for dairy cow production systems arising from climate change in Central Europe - a review.  

PubMed

It is well documented that global warming is unequivocal. Dairy production systems are considered as important sources of greenhouse gas emissions; however, little is known about the sensitivity and vulnerability of these production systems themselves to climate warming. This review brings different aspects of dairy cow production in Central Europe into focus, with a holistic approach to emphasize potential future consequences and challenges arising from climate change. With the current understanding of the effects of climate change, it is expected that yield of forage per hectare will be influenced positively, whereas quality will mainly depend on water availability and soil characteristics. Thus, the botanical composition of future grassland should include species that are able to withstand the changing conditions (e.g. lucerne and bird's foot trefoil). Changes in nutrient concentration of forage plants, elevated heat loads and altered feeding patterns of animals may influence rumen physiology. Several promising nutritional strategies are available to lower potential negative impacts of climate change on dairy cow nutrition and performance. Adjustment of feeding and drinking regimes, diet composition and additive supplementation can contribute to the maintenance of adequate dairy cow nutrition and performance. Provision of adequate shade and cooling will reduce the direct effects of heat stress. As estimated genetic parameters are promising, heat stress tolerance as a functional trait may be included into breeding programmes. Indirect effects of global warming on the health and welfare of animals seem to be more complicated and thus are less predictable. As the epidemiology of certain gastrointestinal nematodes and liver fluke is favourably influenced by increased temperature and humidity, relations between climate change and disease dynamics should be followed closely. Under current conditions, climate change associated economic impacts are estimated to be neutral if some form of adaptation is integrated. Therefore, it is essential to establish and adopt mitigation strategies covering available tools from management, nutrition, health and plant and animal breeding to cope with the future consequences of climate change on dairy farming. PMID:23253935

Gauly, M; Bollwein, H; Breves, G; Brügemann, K; Dänicke, S; Da?, G; Demeler, J; Hansen, H; Isselstein, J; König, S; Lohölter, M; Martinsohn, M; Meyer, U; Potthoff, M; Sanker, C; Schröder, B; Wrage, N; Meibaum, B; von Samson-Himmelstjerna, G; Stinshoff, H; Wrenzycki, C

2013-05-01

195

Maintaining and Restoring Riparian Areas in Grazed Ecosystems  

E-print Network

5/4/2011 1 Maintaining and Restoring Riparian Areas in Grazed Ecosystems Ken Tate ­ UC Davis coastal to Sierra riparian systems ­ there is significant effort to restore riparian areas in grazed watersheds I can be good! We can prescribe grazing to support riparian restoration objectives I Promise

Tate, Kenneth

196

Feed and manure use in low-N-input and high-N-input dairy cattle production systems  

NASA Astrophysics Data System (ADS)

In most parts of Sub-Saharan Africa fertilizers and feeds are costly, not readily available and used sparingly in agricultural production. In many parts of Western Europe, North America, and Oceania fertilizers and feeds are relatively inexpensive, readily available and used abundantly to maximize profitable agricultural production. A case study, dairy systems approach was used to illustrate how differences in feed and manure management in a low-N-input dairy cattle system (Niger, West Africa) and a high-N-input dairy production system (Wisconsin, USA) impact agricultural production and environmental N loss. In Niger, an additional daily feed N intake of 114 g per dairy animal unit (AU, 1000 kg live weight) could increase annual milk production from 560 to 1320 kg AU?1, and the additional manure N could greatly increase millet production. In Wisconsin, reductions in daily feed N intake of 100 g AU?1 would not greatly impact milk production but decrease urinary N excretion by 25% and ammonia and nitrous oxide emissions from manure by 18% to 30%. In Niger, compared to the practice of housing livestock and applying dung only onto fields, corralling cattle or sheep on cropland (to capture urinary N) increased millet yields by 25% to 95%. The additional millet grain due to dung applications or corralling would satisfy the annual food grain requirements of 2–5 persons; the additional forage would provide 120–300 more days of feed for a typical head of cattle; and 850 to 1600 kg ha?1 more biomass would be available for soil conservation. In Wisconsin, compared to application of barn manure only, corralling heifers in fields increased forage production by only 8% to 11%. The application of barn manure or corralling increased forage production by 20% to 70%. This additional forage would provide 350–580 more days of feed for a typical dairy heifer. Study results demonstrate how different approaches to feed and manure management in low-N-input and high-N-input dairy cattle systems impact milk production, manure N excretion, manure N capture, N recycling and environmental N loss.

Powell, J. Mark

2014-11-01

197

Methane emissions from dairy cows: Comparing open-path laser measurements to profile-based techniques  

Microsoft Academic Search

Methane emission rates from a herd of grazing dairy cows were determined from concentration measurements with four open-path lasers positioned around the fenced grazing area. The emission rates were calculated with the aid of a backward-Lagrangian stochastic model (BLS). After discarding data with insufficient laser light levels (due to technical issues discussed in the paper) and periods of light winds,

Johannes Laubach; Francis M. Kelliher

2005-01-01

198

Impacts of Spatial Patterns in Pasture on Animal Grazing Behavior, Intake, and Performance  

Microsoft Academic Search

Control over the quantity and quality of food ingested by grazing ruminants in temperate pasture systems remains elusive. This is due in part to the foraging choices that animals make when grazing from communities of mixed plant species. Grazing behavior and intake interact strongly with the feed supply-demand balance, pasture com- position, and grazing method. These interactions are not completely

D. F. Chapman; A. J. Parsons; G. P. Cosgrove; D. J. Barker; D. M. Marotti; K. J. Venning; S. M. Rutter; J. Hill; A. N. Thompson

2007-01-01

199

Prediction of Breeding Values for Dairy Cattle Using Artificial Neural Networks and Neuro-Fuzzy Systems  

PubMed Central

Developing machine learning and soft computing techniques has provided many opportunities for researchers to establish new analytical methods in different areas of science. The objective of this study is to investigate the potential of two types of intelligent learning methods, artificial neural networks and neuro-fuzzy systems, in order to estimate breeding values (EBV) of Iranian dairy cattle. Initially, the breeding values of lactating Holstein cows for milk and fat yield were estimated using conventional best linear unbiased prediction (BLUP) with an animal model. Once that was established, a multilayer perceptron was used to build ANN to predict breeding values from the performance data of selection candidates. Subsequently, fuzzy logic was used to form an NFS, a hybrid intelligent system that was implemented via a local linear model tree algorithm. For milk yield the correlations between EBV and EBV predicted by the ANN and NFS were 0.92 and 0.93, respectively. Corresponding correlations for fat yield were 0.93 and 0.93, respectively. Correlations between multitrait predictions of EBVs for milk and fat yield when predicted simultaneously by ANN were 0.93 and 0.93, respectively, whereas corresponding correlations with reference EBV for multitrait NFS were 0.94 and 0.95, respectively, for milk and fat production. PMID:22991575

Shahinfar, Saleh; Mehrabani-Yeganeh, Hassan; Lucas, Caro; Kalhor, Ahmad; Kazemian, Majid; Weigel, Kent A.

2012-01-01

200

Prediction of breeding values for dairy cattle using artificial neural networks and neuro-fuzzy systems.  

PubMed

Developing machine learning and soft computing techniques has provided many opportunities for researchers to establish new analytical methods in different areas of science. The objective of this study is to investigate the potential of two types of intelligent learning methods, artificial neural networks and neuro-fuzzy systems, in order to estimate breeding values (EBV) of Iranian dairy cattle. Initially, the breeding values of lactating Holstein cows for milk and fat yield were estimated using conventional best linear unbiased prediction (BLUP) with an animal model. Once that was established, a multilayer perceptron was used to build ANN to predict breeding values from the performance data of selection candidates. Subsequently, fuzzy logic was used to form an NFS, a hybrid intelligent system that was implemented via a local linear model tree algorithm. For milk yield the correlations between EBV and EBV predicted by the ANN and NFS were 0.92 and 0.93, respectively. Corresponding correlations for fat yield were 0.93 and 0.93, respectively. Correlations between multitrait predictions of EBVs for milk and fat yield when predicted simultaneously by ANN were 0.93 and 0.93, respectively, whereas corresponding correlations with reference EBV for multitrait NFS were 0.94 and 0.95, respectively, for milk and fat production. PMID:22991575

Shahinfar, Saleh; Mehrabani-Yeganeh, Hassan; Lucas, Caro; Kalhor, Ahmad; Kazemian, Majid; Weigel, Kent A

2012-01-01

201

Dairy Workers  

MedlinePLUS

... were 94,327 workers in 6,813 dairy cattle and milk production establishments (NAICS code 11212) reported ... An additional 14,355 worked in 1,081 cattle feedlots during 2012 (NAICS code 112112). 3 ? A ...

202

The effects of farm management practices on liver fluke prevalence and the current internal parasite control measures employed on Irish dairy farms.  

PubMed

Fasciolosis caused by Fasciola hepatica is responsible for major production losses in cattle farms. The objectives of this study were to assess the effect of farm management practices on liver fluke prevalence on Irish dairy farms and to document the current control measures against parasitic diseases. In total, 369 dairy farms throughout Ireland were sampled from October to December 2013, each providing a single bulk tank milk (BTM) sample for liver fluke antibody-detection ELISA testing and completing a questionnaire on their farm management. The analysis of samples showed that cows on 78% (n=288) of dairy farms had been exposed to liver fluke. There was a difference (P<0.05) between farms where cows were positive or negative for liver fluke antibodies in (a) the total number of adult dairy cows in herds, (b) the number of adult dairy cows contributing to BTM samples, and (c) the size of the total area of grassland, with positive farms having larger numbers in each case. There was no difference (P>0.05) between positive and negative farms in (a) the grazing of dry cows together with replacement cows, (b) whether or not grazed grassland was mowed for conservation, (c) the type of drinking water provision system, (d) spreading of cattle manure on grassland or (e) for grazing season length (GSL; mean=262.5 days). Also, there were differences (P<0.001) between drainage statuses for GSL with farms on good drainage having longer GSL than moderately drained farms. The GSL for dairy cows on farms with good drainage was 11 days longer than for those with moderate drainage (P<0.001). The percentage of farmers that used an active ingredient during the non-lactating period against liver fluke, gastrointestinal nematodes, lungworm, and rumen fluke was 96%, 85%, 77% and 90%, respectively. Albendazole was the most frequently used active ingredient for treatment against gastrointestinal nematodes (57%), liver fluke (40%) and lungworm (47%), respectively. There was a difference (P<0.05) in the use of triclabendazole and albendazole between positive and negative farms, with triclabendazole use being more common in positive farms. This study highlighted differences in dairy management practices between Irish farms with dairy herds exposed or not exposed to liver fluke and stressed the need of fine-scale mapping of the disease patterns even at farm level to increase the accuracy of risk models. Also, comprehensive advice and professional support services to farmers on appropriate farm management practices are very important for an effective anthelmintic control strategy. PMID:25591405

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

2015-01-30

203

Physical and hydrodynamic characteristics of a dairy shed waste stabilisation pond system.  

PubMed

Waste stabilization pond systems are widely used to treat animal wastes under highly variable hydraulic loading regimes. These systems have received limited research attention with regard to their hydrodynamic behaviour and the potential impact of shock hydraulic loading on their performance. In this study a two-stage dairy shed waste stabilisation pond system was topographically surveyed to determine the physical shape and the theoretical hydraulic retention time (HRT) of each pond, as well as the extent of sludge accumulation in the primary pond. The primary pond was then subjected to a series of drogue tracking runs whereby weighted floating survey targets with submerged 'sails' were tracked during their movement through the pond at times of peak flow in order to characterise the hydrodynamic behaviour of the pond. The full capacity volumes of the primary and secondary ponds were calculated to be 1285 m3 and 2391 m3, respectively. Sludge had been accumulating in the primary pond at a rate of 0.73 m3/d over a period of 2.4 years and this has reduced the active treatment volume of the pond to 657 m3. Based on mean outflow, the HRTs of the ponds were 40 d and 137 d, respectively. The drogue runs revealed a vortex-like mixing pattern within the pond with higher velocities around the perimeter of the pond between the inlet and outlet, and lower velocities in the centre of the pond. In-pond velocities seemed relatively high in comparison with those from other drogue studies of larger ponds and the surging inflow caused the formation of a flow 'jet' that potentially contributed to significant short-circuiting. The range of influence of this flow jet, however, was limited to within 15 m of the inlet, suggesting that short-circuiting would be likely to occur only under certain high inflow conditions. PMID:17591191

Fyfe, J; Smalley, J; Hagare, D; Sivakumar, M

2007-01-01

204

Rangeland Risk Management for Texans: Patch Grazing and Sustainable Rangeland Production  

E-print Network

Patch Grazing and Sustainable Rangeland Production C. Wayne Hanselka, Robert Lyons and Richard Teague Professor and Extension Range Specialist; Associate Professor and Extension Range Specialist; and Associate Professor and Research Scientist..., Texas A&M University System E-172 10-02 Grazing distribution is a major concern to livestock produc- ers because uneven grazing reduces grazeable acres and carrying capacity. Patch grazing is the close and repeated grazing of small patches and...

Hanselka, C. Wayne; Lyons, Robert K.; Teague, Richard

2002-10-28

205

Prescribed grazing on pasturelands  

Technology Transfer Automated Retrieval System (TEKTRAN)

Principles of grazing management center round the temporal and spatial distribution of various kinds and number of livestock. Within the context of this chapter, management of grazing or browsing will be characterized in terms of intensity, method, and season (timing), and as a function of the type ...

206

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

Technology Transfer Automated Retrieval System (TEKTRAN)

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 doc...

207

Soil organic carbon sequestration in grazing systems of the southeastern USA  

Technology Transfer Automated Retrieval System (TEKTRAN)

Improved pasture management systems are needed to restore soil quality, sequester soil organic C, and build the productive capacity of soils in grassland environments so that (1) precipitation can be effectively utilized by plants, (2) water runoff and contaminant transport can be minimized, (3) nat...

208

Induced Fungal Resistance to Insect Grazing: Reciprocal Fitness Consequences and Fungal Gene Expression in the Drosophila-Aspergillus Model System  

PubMed Central

Background Fungi are key dietary resources for many animals. Fungi, in consequence, have evolved sophisticated physical and chemical defences for repelling and impairing fungivores. Expression of such defences may entail costs, requiring diversion of energy and nutrients away from fungal growth and reproduction. Inducible resistance that is mounted after attack by fungivores may allow fungi to circumvent the potential costs of defence when not needed. However, no information exists on whether fungi display inducible resistance. We combined organism and fungal gene expression approaches to investigate whether fungivory induces resistance in fungi. Methodology/Principal Findings Here we show that grazing by larval fruit flies, Drosophila melanogaster, induces resistance in the filamentous mould, Aspergillus nidulans, to subsequent feeding by larvae of the same insect. Larval grazing triggered the expression of various putative fungal resistance genes, including the secondary metabolite master regulator gene laeA. Compared to the severe pathological effects of wild type A. nidulans, which led to 100% insect mortality, larval feeding on a laeA loss-of-function mutant resulted in normal insect development. Whereas the wild type fungus recovered from larval grazing, larvae eradicated the chemically deficient mutant. In contrast, mutualistic dietary yeast, Saccharomyces cerevisiae, reached higher population densities when exposed to Drosophila larval feeding. Conclusions/Significance Our study presents novel evidence that insect grazing is capable of inducing resistance to further grazing in a filamentous fungus. This phenotypic shift in resistance to fungivory is accompanied by changes in the expression of genes involved in signal transduction, epigenetic regulation and secondary metabolite biosynthesis pathways. Depending on reciprocal insect-fungus fitness consequences, fungi may be selected for inducible resistance to maintain high fitness in fungivore-rich habitats. Induced fungal defence responses thus need to be included if we wish to have a complete conception of animal-fungus co-evolution, fungal gene regulation, and multitrophic interactions. PMID:24023705

Caballero Ortiz, Silvia; Trienens, Monika; Rohlfs, Marko

2013-01-01

209

Nutritional regulation of body condition score at the initiation of the transition period in primiparous and multiparous dairy cows under grazing conditions: milk production, resumption of post-partum ovarian cyclicity and metabolic parameters.  

PubMed

The objective of this study was to investigate the effect of different body condition score (BCS) at 30 days before calving (-30 days) induced by a differential nutritional management from -100 days until -30 days on productive parameters, the interval to first ovulation and blood parameters in primiparous and multiparous Holstein cows under grazing conditions until 60 days post partum. The experimental arrangement was a randomized complete block design, where cows were blocked according to BW and expected calving date and then randomly assigned to different nutritional treatments from -100 to -30 days relative to calving to induce different BCS. As the assignment of cows to treatments was random, cows had to lose, maintain or gain BCS; thus, different planes of nutrition were offered with approximately 7, 14 or 20 kg dry matter per day. The BCS score was assessed every 15 days and animals were reassigned in order to achieve the desired BCS at -30 days. Only animals that responded to nutritional treatment were considered and this was defined as follows: primiparous and multiparous high cows (PH and MH) had to gain 0.5 points of BCS, primiparous low (PL) had to lose 0.5 points of BCS and multiparous low (ML) had to maintain BCS at least in two subsequent observations from -100 to -30 days. From -30 days to calving, primiparous and multiparous cows (P and M cows) were managed separately and cows were offered a diet once a day. From calving to 60 days post partum, cows of different groups grazed in separate plots a second year pasture. Cows were also supplemented individually with whole-plant maize silage and commercial concentrate. Cows had similar BCS at -100 days and differed after the nutritional treatment; however, all groups presented similar BCS at 21 days post partum. The daily milk production and milk yield at 60 days post partum was higher in M than P cows. The percentage of milk fat was higher in PH cows compared with PL cows. Concentrations of non-esterified fatty acids (NEFA) were affected by the BCS at -30 days within parity, and in PH cows the concentration of NEFA was higher than in PL cows. The concentrations of total protein were higher in M cows. A lower probability of cycling was found in PL than in PH cows (P < 0.05) and in ML than in MH cows (P < 0.05). Treatment affected various endocrine/metabolic profiles according to parity, suggesting that the metabolic reserves signal the productive/reproductive axis so as to induce a differential nutrient partitioning in adult v. first-calving cows. PMID:22436187

Adrien, M L; Mattiauda, D A; Artegoitia, V; Carriquiry, M; Motta, G; Bentancur, O; Meikle, A

2012-02-01

210

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

211

The Carbon Footprint of Dairy Production Systems through Partial Life Cycle Assessment  

Technology Transfer Automated Retrieval System (TEKTRAN)

Greenhouse gas (GHG) emissions and their potential impact on the environment has become an important national and international concern. 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 fro...

212

Effects of butter from mountain-pasture grazing cows on risk markers of the metabolic syndrome compared with conventional Danish butter: a randomized controlled study  

PubMed Central

Background There is considerable interest in dairy products from low-input systems, such as mountain-pasture grazing cows, because these products are believed to be healthier than products from high-input conventional systems. This may be due to a higher content of bioactive components, such as phytanic acid, a PPAR-agonist derived from chlorophyll. However, the effects of such products on human health have been poorly investigated. Objective To compare the effect of milk-fat from mountain-pasture grazing cows (G) and conventionally fed cows (C) on risk markers of the metabolic syndrome. Design In a double-blind, randomized, 12-week, parallel intervention study, 38 healthy subjects replaced part of their habitual dietary fat intake with 39 g fat from test butter made from milk from mountain-pasture grazing cows or from cows fed conventional winter fodder. Glucose-tolerance and circulating risk markers were analysed before and after the intervention. Results No differences in blood lipids, lipoproteins, hsCRP, insulin, glucose or glucose-tolerance were observed. Interestingly, strong correlations between phytanic acid at baseline and total (P<0.0001) and LDL cholesterol (P=0.0001) were observed. Conclusions Lack of effects on blood lipids and inflammation indicates that dairy products from mountain-pasture grazing cows are not healthier than products from high-input conventional systems. Considering the strong correlation between LDL cholesterol and phytanic acid at baseline, it may be suggested that phytanic acid increases total and LDL cholesterol. Trial registration ClinicalTrials.gov, NCT01343589 PMID:23842081

2013-01-01

213

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.

214

Impacts of stored feed cropping systems and farm size on the profitability of Maine organic dairy farm simulations  

Technology Transfer Automated Retrieval System (TEKTRAN)

U.S. organic dairy production has increased to meet demand for organic milk. Organic dairy farmers have come under increasing financial stress due to increases in concentrated feed prices. Organic dairies in the Northeast U.S. have experimented with different forage and grain crops to maximize on-fa...

215

Grazing Management in Broadleaf Forests  

E-print Network

; Ijssel, 1990, World Bank, 1996; Sangay 1997) and accordingly, dependence on natural regeneration to rejuvenate logged broadleaf forests is thought to be unreliable. This notion has prompted the change of the silvicultural system in broadleaf forests... Studies 102 contrast to these beliefs, some authors viewed that moderate use of forage by cattle in forests is not detrimental to wood production (Tanner and Brantley, 1998). Others advocate that a cattle grazing is an effective management tool...

Norbu, Lungten

2002-01-01

216

The Expanding Dairy Industry: Impact on Ground Water Quality and Quantity with Emphasis on Waste Management System Evaluation for Open Lot Dairies  

E-print Network

and demonstration projects have been initiated since 1988 in response to the concerns about water quality degradation due to open lot dairies. A common goal of these projects is to obtain and disseminate data and information related to the design and evaluation...

Sweeten, John M.; Wolfe, Mary Leigh

217

Traditional vs modern: role of breed type in determining enteric methane emissions from cattle grazing as part of contrasting grassland-based systems.  

PubMed

Ruminant livestock turn forages and poor-quality feeds into human edible products, but enteric methane (CH4) emissions from ruminants are a significant contributor to greenhouse gases (GHGs) and hence to climate change. Despite the predominance of pasture-based beef production systems in many parts of Europe there are little data available regarding enteric CH4 emissions from free-ranging grazing cattle. It is possible that differences in physiology or behaviour could influence comparative emissions intensities for traditional and modern breed types depending on the nutritional characteristics of the herbage grazed. This study investigated the role of breed type in influencing CH4 emissions from growing beef steers managed on contrasting grasslands typical of intensive (lowland) and extensive (upland) production systems. Using the SF6 dilution technique CH4 emissions were estimated for a modern, fast-growing crossbred (Limousin cross) and a smaller and hardier native breed (Welsh Black) when grazing lowland perennial ryegrass (high nutritional density, low sward heterogeneity) and semi-improved upland pasture (low/medium nutritional density, high sward heterogeneity). Live-weight gain was substantially lower for steers on the upland system compared to the lowland system (0.31 vs. 1.04 kg d-1; s.e.d.?=?0.085 kg d-1; P<0.001), leading to significant differences in estimated dry matter intakes (8.0 vs. 11.1 kg DM d-1 for upland and lowland respectively; s.e.d.?=?0.68 kg DM d-1; P<0.001). While emissions per unit feed intake were similar for the lowland and upland systems, CH4 emissions per unit of live-weight gain (LWG) were substantially higher when the steers grazed the poorer quality hill pasture (760 vs 214 g kg-1 LWG; s.e.d.?=?133.5 g kg-1 LWG; P<0.001). Overall any effects of breed type were relatively small relative to the combined influence of pasture type and location. PMID:25259617

Fraser, Mariecia D; Fleming, Hannah R; Moorby, Jon M

2014-01-01

218

Phase behaviour of casein micelles and barley beta-glucan polymer molecules in dietary fibre-enriched dairy systems.  

PubMed

Enrichment of colloidal dairy systems with dietary fibre frequently causes quality defects because of phase separation. We investigate phase separation in skimmed milk enriched with Glucagel (a commercial product made from barley that is predominantly comprised of the polysaccharide ?-glucan). The driving force for phase separation was depletion flocculation of casein micelles in the presence of molecules of the polysaccharide. Depending on the volume fraction of casein micelles and the concentration of Glucagel, the stable system phase separated either as a transient gel or as a sedimented system. The rate at which phase separation progressed also depended on the volume fraction of casein micelles and the concentration of Glucagel. To confirm the role of depletion flocculation in the phase separation process, enzymatic reduction in the molecular weight of ?-glucan was shown to limit the range of attraction between micelles and allow the stable phase to exist at a higher ?-glucan concentration for any given volume fraction of casein micelles. These phase diagrams will be useful to dairy product manufacturers striving to improve the nutrient profile of their products while avoiding product quality impairment. PMID:22484166

Repin, Nikolay; Scanlon, Martin G; Fulcher, R Gary

2012-07-01

219

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...

220

Manual and automatic locomotion scoring systems in dairy cows: a review.  

PubMed

The objective of this review was to describe, compare and evaluate agreement, reliability, and validity of manual and automatic locomotion scoring systems (MLSSs and ALSSs, respectively) used in dairy cattle lameness research. There are many different types of MLSSs and ALSSs. Twenty-five MLSSs were found in 244 articles. MLSSs use different types of scale (ordinal or continuous) and different gait and posture traits need to be observed. The most used MLSS (used in 28% of the references) is based on asymmetric gait, reluctance to bear weight, and arched back, and is scored on a five-level scale. Fifteen ALSSs were found that could be categorized according to three approaches: (a) the kinetic approach measures forces involved in locomotion, (b) the kinematic approach measures time and distance of variables associated to limb movement and some specific posture variables, and (c) the indirect approach uses behavioural variables or production variables as indicators for impaired locomotion. Agreement and reliability estimates were scarcely reported in articles related to MLSSs. When reported, inappropriate statistical methods such as PABAK and Pearson and Spearman correlation coefficients were commonly used. Some of the most frequently used MLSSs were poorly evaluated for agreement and reliability. Agreement and reliability estimates for the original four-, five- or nine-level MLSS, expressed in percentage of agreement, kappa and weighted kappa, showed large ranges among and sometimes also within articles. After the transformation into a two-level scale, agreement and reliability estimates showed acceptable estimates (percentage of agreement ? 75%; kappa and weighted kappa ? 0.6), but still estimates showed a large variation between articles. Agreement and reliability estimates for ALSSs were not reported in any article. Several ALSSs use MLSSs as a reference for model calibration and validation. However, varying agreement and reliability estimates of MLSSs make a clear definition of a lameness case difficult, and thus affect the validity of ALSSs. MLSSs and ALSSs showed limited validity for hoof lesion detection and pain assessment. The utilization of MLSSs and ALSSs should aim to the prevention and efficient management of conditions that induce impaired locomotion. Long-term studies comparing MLSSs and ALSSs while applying various strategies to detect and control unfavourable conditions leading to impaired locomotion are required to determine the usefulness of MLSSs and ALSSs for securing optimal production and animal welfare in practice. PMID:25000863

Schlageter-Tello, Andrés; Bokkers, Eddie A M; Koerkamp, Peter W G Groot; Van Hertem, Tom; Viazzi, Stefano; Romanini, Carlos E B; Halachmi, Ilan; Bahr, Claudia; Berckmans, Daniël; Lokhorst, Kees

2014-09-01

221

36 CFR 222.54 - Grazing fees in the East-competitive bidding.  

Code of Federal Regulations, 2014 CFR

...subpart A of this part. These rules also do not apply to grazing fees on National Forest System lands in Oklahoma or National Grasslands in Texas. (2) Allowable Bidders. Bids for grazing permits shall be accepted from individuals, partnerships,...

2014-07-01

222

36 CFR 222.54 - Grazing fees in the East-competitive bidding.  

Code of Federal Regulations, 2013 CFR

...subpart A of this part. These rules also do not apply to grazing fees on National Forest System lands in Oklahoma or National Grasslands in Texas. (2) Allowable Bidders. Bids for grazing permits shall be accepted from individuals, partnerships,...

2013-07-01

223

36 CFR 222.54 - Grazing fees in the East-competitive bidding.  

Code of Federal Regulations, 2011 CFR

...subpart A of this part. These rules also do not apply to grazing fees on National Forest System lands in Oklahoma or National Grasslands in Texas. (2) Allowable Bidders. Bids for grazing permits shall be accepted from individuals, partnerships,...

2011-07-01

224

36 CFR 222.54 - Grazing fees in the East-competitive bidding.  

Code of Federal Regulations, 2012 CFR

...subpart A of this part. These rules also do not apply to grazing fees on National Forest System lands in Oklahoma or National Grasslands in Texas. (2) Allowable Bidders. Bids for grazing permits shall be accepted from individuals, partnerships,...

2012-07-01

225

ASSESSMENT AND MONITORING OF GRAZING LANDS IN THE NORTHEASTERN UNITED STATES  

Technology Transfer Automated Retrieval System (TEKTRAN)

Dependable technologies are needed to monitor grazing lands, to restore damaged systems, and to identify management practices that increase or maintain economic return while protecting the productive potential of grazed ecosystems. We summarize three pasture assessment and monitoring research effort...

226

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

227

An international terminology for grazing lands and grazing animals  

Technology Transfer Automated Retrieval System (TEKTRAN)

In 1991, Terminology for Grazing Lands and Grazing Animals was published with the objective of ‘developing a consensus of clear definitions of terms used in the grazing of animals.’ During the XVIII International Grassland Congress, held in Canada in 1997, a new Terminology working group was formed ...

228

Grazing Impact on Brood Parasitism  

E-print Network

Anthropogenic land use changes can have tremendous direct and indirect effects on biota. A prevalent land use change in Texas is conversion of land to grazing. Grazing facilitates foraging opportunities for brown-headed cowbirds (Molothrus ater...

Locatelli, Anthony

2014-04-16

229

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

230

Sea surface scattering for near-grazing incidence  

Microsoft Academic Search

The radar cross section of sea clutter at (or near) the horizon is a critical parameter in naval radar system performance evaluation. At the low grazing angles and ranges involved, the existing data base is quite limited. At near-grazing illumination, the radar receives an echo from the sea surface which is characterized by short bursts of power. These are significantly

A. Kbenchaf

1999-01-01

231

Persistence of rotationally grazed red clover in mixed stands.  

Technology Transfer Automated Retrieval System (TEKTRAN)

Red Clover (Trifolium pratense) is an important forage legume in grazing pastures. Historically red clover was limited by its comparatively lower stand persistence in hay and grazed systems. Smith (2000) demonstrated increased persistence under hay management achieved through over 30 years of bree...

232

Cost-effective mitigation of greenhouse gas emissions from different dairy systems in the Waikato region of New Zealand.  

PubMed

The New Zealand dairy industry produces approximately 17% of this country's total greenhouse gas emissions (GHG-e) and it is also this nation's largest export industry. The industry needs to reduce GHG-e under proposed policy directives and for ongoing market security. Given these pressures, there is the need to identify cost-effective management strategies to reduce on-farm GHG-e. The objective of this study was to investigate how the management of dairy farms in the Waikato region of New Zealand could change to minimise the abatement costs associated with GHG-e mitigation. Three typical farm systems importing low (less than 10%), medium (10-20%), and high (more than 20%) amounts of supplement are modelled using a non-linear optimisation model. A reduction in nitrogen fertiliser application was the production factor that changed the most to achieve the cap in all of the simulated systems, followed by a reduction in stocking rate. With the prices used in this study, decreasing farming intensity by reducing nitrogen fertiliser by 21-42% and stocking rate by 8-10% represented a cost of $68-$119/ha and a production reduction of 54-117 kg MS/ha for the three systems studied. Improving reproductive performance proved to be effective in reducing GHG-e, allowing for fewer replacement cows to be supported. However, it did not have a significant effect on profit when emissions were unconstrained. Nitrification inhibitors and stand-off pads were not identified as useful mitigation options, given their high cost relative to de-intensification. PMID:24140485

Adler, Alfredo A; Doole, Graeme J; Romera, Alvaro J; Beukes, Pierre C

2013-12-15

233

The Dairy Greenhouse Gas Emission Model: Reference Manual  

Technology Transfer Automated Retrieval System (TEKTRAN)

The Dairy Greenhouse Gas Model (DairyGHG) is a software tool for estimating the greenhouse gas emissions and carbon footprint of dairy production systems. A relatively simple process-based model is used to predict the primary greenhouse gas emissions, which include the net emission of carbon dioxide...

234

Persistence of Grazed Red Clover Varieties  

Technology Transfer Automated Retrieval System (TEKTRAN)

Historically, red clover (Trifolium pratense) has been limited by its lack of stand persistence in hay and grazed systems compared to other small-seeded forage legumes. Breeding over the past 50 years has extended red clover persistence in a hay management system to four years. This study examined g...

235

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

236

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

237

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...

238

Identifying host sources of fecal pollution: diversity of Escherichia coli in confined dairy and swine production systems.  

PubMed

Repetitive extragenic palindromic PCR fingerprinting of Escherichia coli is one microbial source tracking approach for identifying the host source origin of fecal pollution in aquatic systems. The construction of robust known-source libraries is expensive and requires an informed sampling strategy. In many types of farming systems, waste is stored for several months before being released into the environment. In this study we analyzed, by means of repetitive extragenic palindromic PCR using the enterobacterial repetitive intergenic consensus primers and comparative analysis using the Bionumerics software, collections of E. coli obtained from a dairy farm and from a swine farm, both of which stored their waste as a slurry in holding tanks. In all fecal samples, obtained from either barns or holding tanks, the diversity of the E. coli populations was underrepresented by collections of 500 isolates. In both the dairy and the swine farms, the diversity of the E. coli community was greater in the manure holding tank than in the barn, when they were sampled on the same date. In both farms, a comparison of stored manure samples collected several months apart suggested that the community composition changed substantially in terms of the detected number, absolute identity, and relative abundance of genotypes. Comparison of E. coli populations obtained from 10 different locations in either holding tank suggested that spatial variability in the E. coli community should be accounted for when sampling. Overall, the diversity in E. coli populations in manure slurry storage facilities is significant and likely is problematic with respect to library construction for microbial source tracking applications. PMID:16204513

Lu, Zexun; Lapen, David; Scott, Andrew; Dang, Angela; Topp, Edward

2005-10-01

239

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

240

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

Code of Federal Regulations, 2012 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...

2012-07-01

241

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

Code of Federal Regulations, 2011 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...

2011-07-01

242

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

Code of Federal Regulations, 2014 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...

2014-07-01

243

Greenhouse gas fluxes from experimental dairy barnyards  

Technology Transfer Automated Retrieval System (TEKTRAN)

Dairy production systems are well-established sources of greenhouse gas (GHG) emissions. Dairy cows emit methane (CH4) directly, and contribute to carbon dioxide (CO2), nitrous oxide (N2O), and ammonia (NH3) emissions via manure. The substrate on which manure is deposited is likely a control on GHG ...

244

CONVERTING GIN AND DAIRY WASTES TO METHANE  

Technology Transfer Automated Retrieval System (TEKTRAN)

Alternatives to gin trash and manure disposal would benefit both the cotton ginning and dairy industries. Anaerobic digestion produces both methane gas and a class A soil amendment. Gin and dairy wastes were combined in a two-phase anaerobic system to determine the combinations of temperature, rew...

245

Effects of stored feed cropping systems and farm size on the profitability of Maine organic dairy farm simulations  

Microsoft Academic Search

United States organic dairy production has increased to meet the growing demand for organic milk. Despite higher prices received for milk, organic dairy farmers have come under increasing financial stress due to increases in concentrated feed prices over the past few years, which can make up one-third of variable costs. Market demand for milk has also leveled in the last

A. K. Hoshide; J. M. Halloran; R. J. Kersbergen; T. S. Griffin; S. L. DeFauw; B. J. LaGasse; S. Jain

2011-01-01

246

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

247

Grazing Incidence Solar Telescope  

Microsoft Academic Search

The Grazing Incidence Solar Telescope (GRIST) described in this report is intended for flight in Spacelab and offers for the first time the combination of high spatial and spectral resolution in the XUV and EUV wavelength range. The telescope is a sector shaped Wolter type-2 paraboloid-hyperboloid mirror pair of 412 cm effective focal length, 280 sq cm aperture and 6

R. Pacault; G. P. Whitcomb

1981-01-01

248

Grazing incidence beam expander  

Microsoft Academic Search

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

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

1985-01-01

249

Rangelands and Grazing  

Technology Transfer Automated Retrieval System (TEKTRAN)

Rangelands are a type of land cover dominated by grasses, grass-like plants, forbs, and shrubs, where the land is managed as a natural ecosystem for multiple uses including wildlife habitat, biodiversity, recreation, and grazing by livestock. The area cover by rangelands is 48.2% of the land surfac...

250

Short synchronization system for estrus cycles in dairy heifers: a preliminary report.  

PubMed

In previous studies we demonstrated that the administration of a luteolytic dose of cloprostenol to dairy cows in luteal phase, followed by hCG plus estradiol benzoate (EB) 12 h later, led to successful timed AI 48 h after the initiation of treatment. This article reports two consecutive studies. In Study 1 we determined the pregnancy rate of dairy heifers in luteal phase (established by palpation per rectum) treated with cloprostenol followed by 250 IU of hCG plus 1 mg of EB 12 h later, and inseminated 48 h after cloprostenol injection. Study 2 was designed to evaluate the efficiency this synchronization protocol, irrespective of the estrus stage of the animals. In Study 1, 1272 Friesian heifers aged 14 to 16 months with a palpable corpus luteum received 500 mcg cloprostenol. Heifers were then synchronized either according to the hCG plus EB protocol (hCG-EB, n=637), or by a second dose of cloprostenol 11 d later (PG, n=636). Animals in this last group served as controls and were inseminated 72 and 96 h after the second cloprostenol injection. The pregnancy rate was significantly higher (P<0.0001) in the hCG-EB group (59.5%, 379/637) than in PG (44.8%, 285/636). In Study 2, 135 contemporary heifers (with no corresponding information on estrus stage) were subjected to the same protocol as those in the hCG-EB group of Study 1. These animals were classified in retrospect according to estrus stage established by plasma progesterone concentration. Pregnancy rates were 66.7% (24/36), 51% (25/49) and 58% (29/50) for animals in the follicular, early/late luteal, and mid-luteal phase, respectively. The total pregnancy rate was 57.8% (78/135). These findings indicate an improved pregnancy rate for heifers subjected to single insemination after cloprostenol/hCG/EB synchronization, compared to double insemination after synchronization by 2 cloprostenol injections 11 d apart. The cloprostenol/hCG/EB protocol did result in acceptable pregnancy rates after timed AI of dairy heifers regardless of their estrus cycle phase. PMID:11192177

López-Gatius, F

2000-11-01

251

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

252

Novel in vitro systems for prediction of veterinary drug residues in ovine milk and dairy products.  

PubMed

A new in vitro tool was developed for the identification of veterinary substrates of the main drug transporter in the mammary gland. These drugs have a much higher chance of being concentrated into ovine milk and thus should be detectable in dairy products. Complementarily, a cell model for the identification of compounds that can inhibit the secretion of drugs into ovine milk, and thus reduce milk residues, was also generated. The ATP-binding cassette transporter G2 (ABCG2) is responsible for the concentration of its substrates into milk. The need to predict potential drug residues in ruminant milk has prompted the development of in vitro cell models over-expressing ABCG2 for these species to detect veterinary drugs that interact with this transporter. Using these models, several substrates for bovine and caprine ABCG2 have been found, and differences in activity between species have been reported. However, despite being of great toxicological relevance, no suitable in vitro model to predict substrates of ovine ABCG2 was available. New MDCKII and MEF3.8 cell models over-expressing ovine ABCG2 were generated for the identification of substrates and inhibitors of ovine ABCG2. Five widely used veterinary antibiotics (marbofloxacin, orbifloxacin, sarafloxacin, danofloxacin and difloxacin) were discovered as new substrates of ovine ABCG2. These results were confirmed for the bovine transporter and its Y581S variant using previously generated cell models. In addition, the avermectin doramectin was described as a new inhibitor of ruminant ABCG2. This new rapid assay to identify veterinary drugs that can be concentrated into ovine milk will potentially improve detection and monitoring of veterinary drug residues in ovine milk and dairy products. PMID:24679113

González-Lobato, L; Real, R; Herrero, D; de la Fuente, A; Prieto, J G; Marqués, M M; Alvarez, A I; Merino, G

2014-01-01

253

Review article Grazing and pasture management  

E-print Network

.B. TALLOWIN Soils, Environmental and Ecological Science Department, Institute of Grassland and Environmental) Abstract -- The primary role of grazing animals in grassland biodiversity management is mainte- nance prescriptions with sward-based methods and to integrate biodiversity goals into inten- sive systems. Major gaps

Paris-Sud XI, Université de

254

Tracking Dairy Efficiency  

E-print Network

It is important for dairy operators to review their overall operations regularly and look for inefficiency. Production efficiency in dairies can be improved through changes in culling practices, reproductive efficiency, milk quality and feed rations....

Stokes, Sandra R.

1998-02-10

255

Children and Dairy Chemicals  

MedlinePLUS

... to clean dairy facilities and equipment, especially dairy pipeline cleaners, pose a special risk for children. Rapid ... where the cleaner is pumped directly into the pipeline. This is childproof and protects adult workers from ...

256

Minimising surface water pollution resulting from farm?dairy effluent application to mole?pipe drained soils. I. An evaluation of the deferred irrigation system for sustainable land treatment in the Manawatu  

Microsoft Academic Search

There is little information available on the magnitude of nutrient losses to surface water from the two?pond and daily irrigation treatment systems for farm?dairy effluent (FDE). A research site has been established on a mole?pipe drained Tokomaru silt loam at Massey University's No. 4 Dairy Farm (475 cows) to investigate some of these issues. The site consists of four plots

D. J. Houlbrooke; D. J. Horne; M. J. Hedley; J. A. Hanly; D. R. Scotter; V. O. Snow

2004-01-01

257

Effects of Application of Dairy Slurry on Voluntary Intake of Orchardgrass Hays by Growing Dairy Heifers  

Technology Transfer Automated Retrieval System (TEKTRAN)

Many dairy production systems have a critical need for available sites to land apply dairy slurry after spring planting and during the summer months. One potential option is to apply these nutrients on perennial grass sods; however, this approach is viable only if voluntary intake by livestock is no...

258

Nutritional and ecological evaluation of dairy farming systems based on concentrate feeding regimes in semi-arid environments of Jordan.  

PubMed

The objective of this study was to evaluate the nutritional and ecological aspects of feeding systems practiced under semi-arid environments in Jordan. Nine dairy farms representing the different dairy farming systems were selected for this study. Feed samples (n = 58), fecal samples (n = 108), and milk samples (n = 78) were collected from the farms and analysed for chemical composition. Feed samples were also analysed for metabolisable energy (ME) contents and in vitro organic matter digestibility according to Hohenheim-Feed-Test. Furthermore, fecal nitrogen concentration was determined to estimate in vivo organic matter digestibility. ME and nutrient intakes were calculated based on the farmer's estimate of dry matter intake and the analysed composition of the feed ingredients. ME and nutrient intakes were compared to recommended standard values for adequate supply of ME, utilizable crude protein, rumen undegradable crude protein (RUCP), phosphorus (P), and calcium (Ca). Technology Impact Policy Impact Calculation model complemented with a partial life cycle assessment model was used to estimate greenhouse gas emissions of milk production at farm gate. The model predicts CH4, N2O and CO2 gases emitted either directly or indirectly. Average daily energy corrected milk yield (ECM) was 19 kg and ranged between 11 and 27 kg. The mean of ME intake of all farms was 184 MJ/d with a range between 115 and 225 MJ/d. Intake of RUCP was lower than the standard requirements in six farms ranging between 19 and 137 g/d, was higher (32 and 93 g/d) in two farms, and matched the requirements in one farm. P intake was higher than the requirements in all farms (mean oversupply = 19 g/d) and ranged between 3 and 30 g/d. Ca intake was significantly below the requirements in small scale farms. Milk nitrogen efficiency N-eff (milk N/intake N) varied between 19% and 28% and was mainly driven by the level of milk yield. Total CO2 equivalent (CO2 equ) emission ranged between 0.90 and 1.88 kg CO2/kg ECM milk, where the enteric and manure CH4 contributed to 52% of the total CO2 equ emissions, followed by the indirect emissions of N2O and the direct emissions of CO2 gases which comprises 17% and 15%, respectively, from total CO2 equ emissions. Emissions per kg of milk were significantly driven by the level of milk production (r (2) = 0.93) and of eDMI (r (2) = 0.88), while the total emissions were not influenced by diet composition. A difference of 16 kg ECM/d in milk yield, 9% in N-eff and of 0.9 kg CO2 equ/kg in ECM milk observed between low and high yielding animals. To improve the nutritional status of the animals, protein requirements have to be met. Furthermore, low price by-products with a low carbon credit should be included in the diets to replace the high proportion of imported concentrate feeds and consequently improve the economic situation of dairy farms and mitigate CO2 equ emissions. PMID:24596499

Alqaisi, Othman; Hemme, Torsten; Hagemann, Martin; Susenbeth, Andreas

2014-01-01

259

Development of a laboratory scale clean-in-place system to test the effectiveness of "natural" antimicrobials against dairy biofilms.  

PubMed

A laboratory scale system, partially reproducing dairy plant conditions, was developed to quantify the effectiveness of chlorine and alternative sanitizers in reducing the number of viable bacteria attached to stainless steel surfaces. Stainless steel tubes fouled in a continuous flow reactor were exposed to a standard clean-in-place regime (water rinse, 1% sodium hydroxide at 70 degrees C for 10 min, water rinse, 0.8% nitric acid at 70 degrees C for 10 min, water rinse) followed by exposure to either chlorine (200 ppm) or combinations of nisin (500 ppm), lauricidin (100 ppm), and the lactoperoxidase system (LPS) (200 ppm) for 10 min or 2, 4, 8, 18, or 24 h. There was significant variation in the effectiveness of the alkaline-acid wash steps in reducing cell numbers (log reduction between 0 and 2). Following a 10-min treatment, none of the sanitizers significantly reduced the number of attached cells. Two hours of exposure to chlorine, nisin + the LPS, or lauricidin + the LPS achieved 2.8, 2.2, and 1.6 log reductions, respectively. Exposure times > 2 h did not further decrease the number of viable bacteria attached to the stainless steel. The effectiveness of combinations of nisin, lauricidin, and the LPS was similar to that of chlorine (P > 0.05), and these sanitizers could be used to decontaminate the surfaces of small-volume or critical hard-to-clean milk processing equipment. PMID:15270498

Dufour, Muriel; Simmonds, Robin S; Bremer, Phil J

2004-07-01

260

Managing forage and grazing lands for multiple ecosystem services  

Technology Transfer Automated Retrieval System (TEKTRAN)

Forage and grazing land systems are increasingly expected to provide services beyond food, feed, and fiber. The concept of multifunctionality in grassland agriculture recognizes ecosystem services beyond these traditional functions to include emerging services such as carbon sequestration, greenhous...

261

Measuring methane emission rates of a dairy cow herd by two micrometeorological techniques  

Microsoft Academic Search

Two well-known micrometeorological techniques were used to measure methane emission rates from a herd of dairy cows freely grazing within a fenced paddock. The integrated horizontal flux technique (IHF) was preferable to the flux-gradient technique (FG) because it does not rely on similarity assumptions, and because it had the smaller measurement error. Both techniques were comparable, within estimated errors, with

Johannes Laubach; Francis M. Kelliher

2004-01-01

262

Meat Production in a Feedlot System of Zebu—Holstein Steers and Heifers with Dairy Genetics: Productive and Biological Analyses  

PubMed Central

The aim of this study was to evaluate the productive and biological efficiency of steers and heifers from dairy genetics in a feedlot system in terms of meat production. Twenty-four steers and 24 heifers at 10 monthes of age, (3/4) Zebu × (1/4) Holstein were utilized. They were distributed over four feedlot times, 30, 60, 90, and 120 days with four replications for each sex, and were slaughtered at the end of each period. The productive and biological analyses were performed through comparative slaughter to determine the body composition. Heifers presented with greater intakes (P < 0.05) of dry matter in grams per kg of body weight. Steers presented with a greater (P < 0.05) final empty body weight, carcass gain, cold carcass weight, and meat proportion in the carcass; however, heifers presented with a greater subcutaneous fat thickness (P < 0.05) and, consequently, a greater (P < 0.05) fat proportion in the carcass. We conclude that steers are more efficient in their productive performance than heifers in a feedlot. For the finishing carcass fat cover, heifers need 90 days in the feedlot. The net energy requirements for maintenance are 67?kcal/EBW0.75/d, and the net requirements of energy (NEg) and protein (NPg) for gain can be estimated by the following equations: NEg(Mcal/d) = 0.067 × EBW0.75 × EBG1.095 and NPg = 162 × EBG ? 5.62 × RE for the two sexes. PMID:25574483

Menezes, Gustavo Chamon de Castro; Valadares Filho, Sebastião de Campos; Ruas, José Reinaldo Mendes; Detmann, Edenio; Menezes, Arismar de Castro; Zanett, Diego; Mariz, Lays Débora Silva; Rennó, Luciana Navajas; da Silva Junior, Jarbas Miguel

2014-01-01

263

[Influence of floor surface and access to pasture on claw characteristics in dairy cows kept in cubicle housing systems].  

PubMed

This study aimed at investigating the effect of the floor type used in the walking area of cubicle housing systems and of access to pasture on claw dimensions and claw shape in dairy cows. Data were collected on 36 farms, 12 farms each fitted with mastic asphalt, slatted concrete or solid rubber flooring. With each floor type, cows on half of the farms had access to pasture in summer. The farms were visited three times at intervals of about 6 months and data were collected from 10 cows during each visit. Net growth of the claw horn was highest on rubber flooring and lowest on mastic asphalt. On all floor types, claw angles were larger after the winter period and smaller after the summer period. With regard to claw shape, floor type had an effect on the occurrence of flat, concave and overgrown claw soles. In conclusion, none of the investigated floor types was clearly superior to the others with regard to claw dimensions and claw shape, and access to pasture during summer (median 4 h per day) had only little influence on the investigated claw characteristics. PMID:24686817

Haufe, H C; Friedli, K; Gygax, L; Wechsler, B

2014-04-01

264

A comparison of the effects of 2 cattle-cooling systems on dairy cows in a desert environment.  

PubMed

An experiment was conducted to investigate the effects of operation time and size of Korral Kool (KK; Korral Kool Inc., Mesa, AZ) systems on core body temperature (CBT) of dairy cows. Two KK systems were compared: a system with 1.29-m-diameter, 3-hp fans spaced 6 m apart (referred to as small) and a system with 1.52-m-diameter, 5-hp fans spaced 8 m apart (referred to as big). Forty-eight multiparous Holstein cows were assigned randomly to 8 pens (4 big, 4 small), and pens were assigned randomly to a sequence of treatments (KK operated for 21 or 24 h/d) in a switchback design. A complementary calorimetric analysis was developed to investigate the cooling area under the KK units of the big and small systems. Twenty-five sensors distributed equally under the KK units measured ambient temperature at 5-min intervals for 2 h. Average ambient temperature was 35.0±0.6°C and relative humidity was 45±8%. There were significant treatment effects on mean CBT: cows on the small 24-h treatment had a lower mean CBT than cows on the small 21-h treatment (39.22 vs. 39.36±0.14°C), and cows on the big 24-h treatment had a lower mean CBT than cows on the big 21-h treatment (38.95 vs. 39.09±0.13°C). A significant treatment by time interaction was observed. The greatest difference between systems occurred at 0100 h; treatment means at this time were 39.05, 39.01, 39.72, and 39.89±0.16°C for the big 24-h, big 21-h, small 24-h, and small 21-h treatments, respectively. At certain times of day, the big system reduced CBT more than the small system. These results show that CBT of multiparous cows decreased when KK system operational time was increased from 21 to 24 h regardless of the size of the KK cooling system used. The calorimetric analysis showed that even though the big system resulted in lower mean ambient temperatures than the small system, the distance between units in the big system should be decreased to reduce the variation in temperature under the big units. PMID:20855030

Ortiz, X A; Smith, J F; Bradford, B J; Harner, J P; Oddy, A

2010-10-01

265

Grazing incidence mirrors for EUV lithography  

Microsoft Academic Search

Extreme UV lithography is one of the most favoured options for the next generation of lithography systems, being considered as one of the keys of the 50 nm technology node. ZrN\\/TiN, multi-layered coatings for mirrors with high reflectivity at grazing incidence for EUV radiation (13.5) are proposed as coatings for the collection mirror in an EUVL system. These films were

V. Braic; M. Balaceanu; M. Braic

2008-01-01

266

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

267

Ingestive behaviour of heifers grazing monocultures of ryegrass or white clover  

Microsoft Academic Search

The ingestive behaviour of dairy heifers grazing monocultures of either perennial ryegrass or white clover was characterised. Two different types of jaw movements were characterised: bites (i.e. when herbage was gathered in to the mouth and then severed) and chews (i.e. when herbage severed by a bite was processed before swallowing). The heifers had a total jaw movement rate (i.e.

S. M Rutter; R. J Orr; P. D Penning; N. H Yarrow; R. A Champion

2002-01-01

268

Grazing incidence X-ray microscopy of laser fusion targets  

Microsoft Academic Search

Grazing-incidence X-ray microscopy is used to diagnose laser fusion plasmas. The characteristics of the four-channel X-ray microscope systems currently employed are given, noting that vitreous carbon and gold reflectors have been introduced in order to extend imaging capability below 1.0 keV and above 3.0 keV. Axisymmetric grazing-incidence X-ray microscope configurations have been analyzed in order to obtain improved spatial resolution

M. J. Boyle

1977-01-01

269

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

270

Nitrogen Mineralization by Acanthamoeba polyphaga in Grazed Pseudomonas paucimobilis Populations  

PubMed Central

Nitrogen mineralization was studied in a simple grazing system in which the protozoan Acanthamoeba polyphaga was grown with the bacterium Pseudomonas paucimobilis (two soil organisms isolated from the shortgrass prairie in northern Colorado). In different experiments, either carbon or nitrogen was adjusted to be in limiting amounts. When carbon was limiting, grazers were almost entirely responsible for nitrogen mineralization, with bacteria themselves contributing little. When nitrogen was limiting, nitrogen mineralization by grazers permitted continued growth by the grazed bacteria and a greater bacterial biomass production. The increased growth of the grazed bacteria did not result in an increased total amount of carbon used, but the grazed bacteria used carbon more efficiently than the ungrazed bacteria. PMID:16345864

Sinclair, James L.; McClellan, J. Forbes; Coleman, David C.

1981-01-01

271

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

272

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. PMID:25049870

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

2013-01-01

273

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

PubMed

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. PMID:25049870

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

2013-07-01

274

Persistent, Toxin-Antitoxin System-Independent, Tetracycline Resistance-Encoding Plasmid from a Dairy Enterococcus faecium Isolate?  

PubMed Central

A tetracycline-resistant (Tetr) 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 Tetr 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.

2011-01-01

275

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

276

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

277

Modification of immune responses and digestive system microbiota of lactating dairy cows by feeding Bovamine(R)  

Technology Transfer Automated Retrieval System (TEKTRAN)

We evaluated the immune modulatory effects as well as effects on productivity of Bovamine® (Lactobacillus acidophilus strain NP51 and Probionibacterium freudenreichii) fed to Holstein and Jersey dairy cows during late lactation (average DIM = 202.44 days on wk-0). Cows were randomized to treatment g...

278

Planning for Profitable Dairying.  

E-print Network

Content? Summary Six factors influence greatly the profits from Grade "4' milk production, as shown by this study of dairy farm operation; in East and Central Texas, with additional data from experimen. tal dairy herds at Substation No. 2... at Tyler, Texas. ......................... 1 Summary ~tluction ... Intrt Purr -r\\ Procedure >ose and _ 1- 1. High average production is extremely important to pra I fitable dairying. At the average price paid for milk tetting 4 percent butterfat...

Magee, A. C.; Stone, B. H.; Leighton, R. E.; Carpenter, S. E.

1961-01-01

279

Sustainability of US organic beef and dairy production systems: soil, plant and cattle interactions  

Technology Transfer Automated Retrieval System (TEKTRAN)

In 2010, the National Organic Program implemented a rule stating that pasture must be a significant source of feed in organic ruminant systems. This article will focus on how this rule has impacted the management, economics and nutritional value of products derived from organic ruminant systems and ...

280

Improving Accuracy of the United States Genetics Database with a New Editing System for Dairy Records  

Microsoft Academic Search

A new editing system for records used to compute USDA-DHIA genetic evaluations was developed to allow im- mediate and more complete checking of data. The system uses direct (immediate on-line) access to pedigree and some lac- tation information to evaluate new data received. Birth dates are checked against parent birth dates and dam calving dates. For most conflicts, existing data

H. D. Norman; L. G. Waite; G. R. Wiggans; L. M. Walton

1994-01-01

281

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

NASA Astrophysics Data System (ADS)

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+ 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 × 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+ fluences < 15.6 × 1014 ion/cm2 (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 (? = 1.56 × 1014 ion/cm2) can be represented by an interfacial-intermixed layer (NixFeyAu(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.; Hase, Thomas P. A.; Atkinson, Del

2012-02-01

282

Modelling of ammonia emissions from dairy cow houses  

Microsoft Academic Search

Dairy cow husbandry contributes to environmental acidification through the emission of ammonia. In-depth knowledge on the processes and variable factors that play a role in the emission of ammonia from dairy cow houses benefits the production of emission data, the development of low emission housing systems, and evaluation of emission levels in a farming system approach. A mechanistic simulation model

G. J. Monteny

2000-01-01

283

The impact of grazing management on Orthoptera abundance varies over the season in Mediterranean steppe-like grassland  

NASA Astrophysics Data System (ADS)

As semi-natural grassland has a high level of biological diversity, understanding the effects of grazing and its variation over time is important in order to identify sustainable grazing practices. We measured temporal variation in Orthoptera abundance and spatial vegetation structure during seasonal grazing in an extensive sheep-farming system. We studied five grazed pasture areas (pre-grazing and post-grazing) and two adjacent ungrazed grasslands. We recorded the total abundance of Orthoptera and described the vegetation structure of 175 replicate plots (25 per pasture/grassland) during six field sampling sessions. We demonstrated that the impact of grazing on Orthoptera abundance is species-specific and greatly varies over the grazing season. The decrease of phytovolume is significant after 4-7 weeks of sheep grazing. Total Orthoptera abundance was higher in pre-grazed plots than in ungrazed plots, and higher in ungrazed plots than in post-grazed plots. These differences were particularly high during the peak of adult abundance. No difference in species richness was observed between grazing intensities. Total Orthoptera abundance positively correlated to phytovolume only when grazing pressure was high. However, the relationship between abundance and phytovolume differed between species. Extensive grazing by sheep tends to homogenize spatial vegetation structure and to temporarily reduce total Orthoptera abundance at pasture scale. However, rotational grazing allows spatial and temporal heterogeneity in vegetation structure to be maintained at farm scale, heterogeneity that is beneficial for Orthoptera. In contrast, absence of grazing has a negative impact on Orthoptera abundance as it favours the accumulation of litter, which is detrimental for a high proportion of xerothermophilic Orthoptera associated with bare ground and short vegetation.

Fonderflick, Jocelyn; Besnard, Aurélien; Beuret, Aurore; Dalmais, Mathieux; Schatz, Bertrand

2014-10-01

284

The Mgeta Integrated Farming System with Emphasis on the Introduction of Norwegian Dairy Goats  

Microsoft Academic Search

Summary • This article describes the Mgeta, Tanzania mixed farming system which comprises of food production, vegetable gardening, fruit production and animals husbandry. Pigs, goats and poultry are the main livestock species. Maize, beans and peas are the major food crops in the area. There are a variety of vegetables and temperate fruits being grown for sale though some are

G. C. Kifaro; L. A. Mtenga; S. M. Kiango

2000-01-01

285

Energy utilization in crop and dairy production in organic and conventional livestock production systems  

Microsoft Academic Search

Searching for livestock production systems with a high energy utilization is of interest because of resource use and pollution aspects and because energy use is an indicator of the intensification of production processes. Due to interactions between crop and livestock enterprises and between levels of different input factors and their effects on yields, it is proposed to analyze agricultural energy

Karen Refsgaard; Niels Halberg; Erik Steen Kristensen

1998-01-01

286

The effect of pasture allowance and supplementation on feed efficiency and profitability of dairy systems.  

PubMed

Partial budgeting was used to compare income over feed costs of high-yielding Holstein cows based on data from an experiment with 4 dietary treatments arranged in a 2 x 2 factorial. The factors were low (25 kg DM/cow per day) and high (40 kg DM/cow per day) pasture allowance (PA) and supplemental grain fed at 1 kg/4 kg of milk or no supplemental grain fed. The 4 treatments were low PA unsupplemented (LPAU), low PA concentrate supplementation (LPAC), high PA unsupplemented (HPAU), and high PA concentrate supplementation (HPAC). Two management systems were modeled. The first, a fixed herd size flexible rotation length model, and the second, a flexible herd size model where rotation length was fixed. The LPAC treatment yielded the highest income over feed costs, followed by the HPAC treatment. The treatment generating the lowest income was the HPAU system. The low PA systems generated more income than did the high PA systems for equivalent supplemental feeding strategies. The results also showed that feeding supplemental grain increased the income-over-feed costs compared with systems that did not feed supplemental grain. In most treatments, comparing the fixed herd against the flexible herd models, the flexible herd size model generated higher income due to the substitution of relatively low income per hectare of hay production for higher income from milk production. There were also differences in feed conversion efficiencies for milk production due to concentrate supplementation (1.04 unsupplemented vs. 1.21 supplemented), but PA did not affect the efficiency of milk production. Neither supplementation nor PA affected the feed conversion efficiency of milk fat yield. However, the efficiency of milk protein yield was affected by concentrate supplementation (0.028 unsupplemented vs. 0.034 supplemented) but not by pasture allowance. PMID:15375051

Tozer, P R; Bargo, F; Muller, L D

2004-09-01

287

Texturized dairy proteins  

Technology Transfer Automated Retrieval System (TEKTRAN)

Dairy proteins are amenable to structural modifications induced by high temperature, shear and moisture; in particular, whey proteins can change conformation to new unfolded states. The change in protein state is a basis for creating new foods. The dairy products, nonfat dried milk (NDM), whey prote...

288

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

289

Measuring methane emission rates of a dairy cow herd (II): results from a backward-Lagrangian stochastic model  

Microsoft Academic Search

We apply a backward-Lagrangian stochastic (BLS) model to determine methane (CH4) emission rates from a herd of dairy cows freely grazing pasture within a fenced paddock. We assess how model characteristics and measurement errors of the input variables contribute to the error of the emission rate. This error is of order 20%. We find a scattered but systematic trend for

Johannes Laubach; Francis M. Kelliher

2005-01-01

290

Methane and ammonia emissions from New Mexico dairy lagoons in summer  

Technology Transfer Automated Retrieval System (TEKTRAN)

Gaseous emissions of concern from commercial dairy operations include methane and ammonia. Dairy wastewater lagoons are sources of emission for both these gases. We quantified emissions of methane and ammonia from a lagoon system at a commercial open lot dairy in eastern New Mexico using open path l...

291

Exploring the conventionalization of organic dairy: trends and counter-trends in upstate New York  

Microsoft Academic Search

Stakeholders in traditional dairy-producing states in the upper Midwest and Northeast hope that the boom in the organic milk\\u000a market will offer family-scale dairy farms a means to escape the cost-price squeeze of the conventional food system. However,\\u000a recent trends in organic dairy raise questions about whether organic dairy is conventionalizing, which is to say it is coming\\u000a to resemble

Amy Guptill

2009-01-01

292

Questionnaire-based study to assess the association between management practices and mastitis within tie-stall and free-stall dairy housing systems in Switzerland  

PubMed Central

Background Prophylactic measures are key components of dairy herd mastitis control programs, but some are only relevant in specific housing systems. To assess the association between management practices and mastitis incidence, data collected in 2011 by a survey among 979 randomly selected Swiss dairy farms, and information from the regular test day recordings from 680 of these farms was analyzed. Results The median incidence of farmer-reported clinical mastitis (ICM) was 11.6 (mean 14.7) cases per 100 cows per year. The median annual proportion of milk samples with a composite somatic cell count (PSCC) above 200,000 cells/ml was 16.1 (mean 17.3) %. A multivariable negative binomial regression model was fitted for each of the mastitis indicators for farms with tie-stall and free-stall housing systems separately to study the effect of other (than housing system) management practices on the ICM and PSCC events (above 200,000 cells/ml). The results differed substantially by housing system and outcome. In tie-stall systems, clinical mastitis incidence was mainly affected by region (mountainous production zone; incidence rate ratio (IRR) = 0.73), the dairy herd replacement system (1.27) and farmers age (0.81). The proportion of high SCC was mainly associated with dry cow udder controls (IRR = 0.67), clean bedding material at calving (IRR = 1.72), using total merit values to select bulls (IRR = 1.57) and body condition scoring (IRR = 0.74). In free-stall systems, the IRR for clinical mastitis was mainly associated with stall climate/temperature (IRR = 1.65), comfort mats as resting surface (IRR = 0.75) and when no feed analysis was carried out (IRR = 1.18). The proportion of high SSC was only associated with hand and arm cleaning after calving (IRR = 0.81) and beef producing value to select bulls (IRR = 0.66). Conclusions There were substantial differences in identified risk factors in the four models. Some of the factors were in agreement with the reported literature while others were not. This highlights the multifactorial nature of the disease and the differences in the risks for both mastitis manifestations. Attempting to understand these multifactorial associations for mastitis within larger management groups continues to play an important role in mastitis control programs. PMID:24107254

2013-01-01

293

Fortification of cheese with vitamin D3 using dairy protein emulsions as delivery systems.  

PubMed

Vitamin D is an essential vitamin that is synthesized when the body is exposed to sunlight or after the consumption of fortified foods and supplements. The purpose of this research was to increase the retention of vitamin D(3) in Cheddar cheese by incorporating it as part of an oil-in-water emulsion using a milk protein emulsifier to obtain a fortification level of 280 IU/serving. Four oil-in-water vitamin D emulsions were made using sodium caseinate, calcium caseinate, nonfat dry milk (NDM), or whey protein. These emulsions were used to fortify milk, and the retention of vitamin D(3) in cheese curd in a model cheesemaking system was calculated. A nonemulsified vitamin D(3) oil was used as a control to fortify milk. Significantly more vitamin D(3) was retained in the curd when using the emulsified vitamin D(3) than the nonemulsified vitamin D(3) oil (control). No significant differences were observed in the retention of vitamin D(3) when emulsions were formulated with different emulsifiers. Mean vitamin D(3) retention in the model system cheese curd was 96% when the emulsions were added to either whole or skim milk compared with using the nonemulsified oil, which gave mean retentions of only 71% and 64% when added to whole and skim milk, respectively. A similar improvement in retention was achieved when cheese was made from whole and reduced-fat milk using standard manufacturing procedures on a small scale. When sufficient vitamin D(3) was added to produce cheese containing a target level of approximately 280 IU per 28-g serving, retention was greater when the vitamin D(3) was emulsified with NDM than when using nonemulsified vitamin D(3) oil. Only 58±3% of the nonemulsified vitamin D(3) oil was retained in full-fat Cheddar cheese, whereas 78±8% and 74±1% were retained when using the vitamin D(3) emulsion in full-fat and reduced-fat Cheddar cheese, respectively. PMID:22916880

Tippetts, M; Martini, S; Brothersen, C; McMahon, D J

2012-09-01

294

Molecular packing in new Langmuir-Blodgett systems investigated by X-ray specular reflectivity and grazing incidence X-ray diffraction  

Microsoft Academic Search

In this work we investigate the periodic arrangementand crystalline order of Langmuir-Blodgett multilayers of a perylene-3,4,9,10-tetracarboxyldimide derivative (PTCDI-Opent) and of a long chain ammonium salt of 12-phosphomolybdate (PMo12O403?) deposited on (111)-oriented Si substrates by X-ray specular reflectivity (XSR) and grazing incidence X-ray diffraction measurements (GIXD). This is the first experimental study of the structural order performed on these complex compounds.

C. Giannini; L. Tapfer; M. Sauvagesimkin; Y. Garreau; N. Jedrecy; M. B. Véron; R. Pinchaux; M. Burghard; S. Roth

1996-01-01

295

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 ...

296

43 CFR 9239.3 - Grazing, Alaska.  

Code of Federal Regulations, 2013 CFR

...SERVICES (9000) TRESPASS Kinds of Trespass § 9239.3 Grazing, Alaska. (a) Reindeer. (1) Any use of the Federal lands for reindeer grazing purposes, unless authorized by a valid permit issued in accordance with the...

2013-10-01

297

43 CFR 9239.3 - Grazing, Alaska.  

Code of Federal Regulations, 2011 CFR

...SERVICES (9000) TRESPASS Kinds of Trespass § 9239.3 Grazing, Alaska. (a) Reindeer. (1) Any use of the Federal lands for reindeer grazing purposes, unless authorized by a valid permit issued in accordance with the...

2011-10-01

298

43 CFR 9239.3 - Grazing, Alaska.  

Code of Federal Regulations, 2014 CFR

...SERVICES (9000) TRESPASS Kinds of Trespass § 9239.3 Grazing, Alaska. (a) Reindeer. (1) Any use of the Federal lands for reindeer grazing purposes, unless authorized by a valid permit issued in accordance with the...

2014-10-01

299

43 CFR 9239.3 - Grazing, Alaska.  

Code of Federal Regulations, 2012 CFR

...SERVICES (9000) TRESPASS Kinds of Trespass § 9239.3 Grazing, Alaska. (a) Reindeer. (1) Any use of the Federal lands for reindeer grazing purposes, unless authorized by a valid permit issued in accordance with the...

2012-10-01

300

36 CFR 292.48 - Grazing activities.  

Code of Federal Regulations, 2012 CFR

...cultural, fish and wildlife, and other resources in the HCNRA. (d) The authorization of grazing use, through a grazing permit, must provide for terms and conditions which protect and conserve riparian...

2012-07-01

301

36 CFR 292.48 - Grazing activities.  

Code of Federal Regulations, 2010 CFR

...cultural, fish and wildlife, and other resources in the HCNRA. (d) The authorization of grazing use, through a grazing permit, must provide for terms and conditions which protect and conserve riparian...

2010-07-01

302

36 CFR 292.48 - Grazing activities.  

Code of Federal Regulations, 2011 CFR

...cultural, fish and wildlife, and other resources in the HCNRA. (d) The authorization of grazing use, through a grazing permit, must provide for terms and conditions which protect and conserve riparian...

2011-07-01

303

36 CFR 292.48 - Grazing activities.  

Code of Federal Regulations, 2013 CFR

...cultural, fish and wildlife, and other resources in the HCNRA. (d) The authorization of grazing use, through a grazing permit, must provide for terms and conditions which protect and conserve riparian...

2013-07-01

304

36 CFR 292.48 - Grazing activities.  

Code of Federal Regulations, 2014 CFR

...cultural, fish and wildlife, and other resources in the HCNRA. (d) The authorization of grazing use, through a grazing permit, must provide for terms and conditions which protect and conserve riparian...

2014-07-01

305

Herbage intake rates and grazing behaviour of sheep and goats grazing grass or white clover  

E-print Network

Herbage intake rates and grazing behaviour of sheep and goats grazing grass or white clover PD grazing times than those grazing grass (Penning et al, 1991, Appl Anim Beh Sci, 31, 237-250). To examine animals. The experiment had a 2 (sheep or goats) x 2 (grass or clover) factorial design with treatments

Paris-Sud XI, Université de

306

Food intake of grazing ruminants with emphasis on Mediterranean grazing lands  

E-print Network

Food intake of grazing ruminants with emphasis on Mediterranean grazing lands AS Nastis R Cordesse Zootechnie Méditerranéenne, Place Viala, Montpellier, France Summary - Mediterranean grazing lands provide at pasture and methods used to determine consumption of grazing animals with emphasis on the Mediterranean

Boyer, Edmond

307

Effects of grazing intensity and chemical seedhead suppression on steers grazing tall fescue pastures  

Technology Transfer Automated Retrieval System (TEKTRAN)

The first year of a 2 yr grazing study was conducted to evaluate use of Chaparral™ to suppress reproductive growth in tall fescue grazed with low and moderate grazing intensities. Chaparral applications (0 and 2.0 oz/acre) and grazing intensities were arranged as RCBD with three replications. Variab...

308

DAIRY PHOSPHORUS CONSIDERATIONS IN DAIRY MANAGEMENT  

Technology Transfer Automated Retrieval System (TEKTRAN)

Reducing dietary P intake to recommended levels is an important practice for improving mutrient management on Wisconsin's dairy farms. A goal of dietary P management should be to avoid overfeeding of P which, in turn, avoids the increase in manure-P content. Over-feeding P increases the amount of ...

309

75 FR 72785 - Dairy Industry Advisory Committee; Public Meeting  

Federal Register 2010, 2011, 2012, 2013, 2014

...Committee (Dairy Committee) to discuss farm milk price volatility and dairy farmer profitability...Dairy Committee reviews issues of farm milk price volatility and dairy farmer profitability...Dairy Committee is to: Discuss farm milk price volatility and dairy farmer...

2010-11-26

310

The Brewster angle effect on sea surface scattering for near-grazing incidence  

Microsoft Academic Search

The radar cross section of sea clutter at (or near) the horizon is a critical parameter in naval radar system performance evaluation. At the low grazing angles and ranges involved, the existing data base is quite limited. At near-grazing illumination, the radar receives an echo from the sea surface which is characterized by short bursts of power. These are significantly

A. KiYENChYF; Rue Christian Pauc

1999-01-01

311

Non-destructive assessment of cattle forage selection: A test of skim grazing in fescue grassland  

Microsoft Academic Search

This study evaluated a non-destructive scientific method that is non-invasive to the animal, for quantifying foraging selectivity by cattle within heterogeneous pasture swards in order to test the utility of a new grazing system designed to aid conservation of native rough fescue (Festuca campestris Rydb.) rangeland in western Canada. Skim grazing is a recently developed strategy that involves a light,

Darlene M. Moisey; Edward W. Bork; Walter D. Willms

2005-01-01

312

Festuca campestris alters root morphology and growth in response to simulated grazing and nitrogen form  

Microsoft Academic Search

Summary 1. Large herbivores are known to spatially concentrate and alter the form of nitrogen (N) in grassland systems, which can modify aboveground plant chemical composition and productiv- ity, and result in shifts in grazing pressure in these areas. Root responses to grazing under high N inputs may facilitate these changes, but their responses are less well understood. 2. We

Leslie E. McInenly; Evelyn H. Merrill; James F. Cahill; Noorallah G. Juma

313

25 CFR 700.709 - Grazing privileges.  

Code of Federal Regulations, 2012 CFR

...of individuals eligible for New Lands grazing permits who: (1) Have a current HPL grazing permit, or have had an HPL permit issued since 1980, or are current HPL residents and can show documentation of a past grazing permit issued in their...

2012-04-01

314

25 CFR 700.709 - Grazing privileges.  

Code of Federal Regulations, 2013 CFR

...of individuals eligible for New Lands grazing permits who: (1) Have a current HPL grazing permit, or have had an HPL permit issued since 1980, or are current HPL residents and can show documentation of a past grazing permit issued in their...

2013-04-01

315

25 CFR 700.709 - Grazing privileges.  

Code of Federal Regulations, 2014 CFR

...of individuals eligible for New Lands grazing permits who: (1) Have a current HPL grazing permit, or have had an HPL permit issued since 1980, or are current HPL residents and can show documentation of a past grazing permit issued in their...

2014-04-01

316

25 CFR 700.709 - Grazing privileges.  

Code of Federal Regulations, 2011 CFR

...of individuals eligible for New Lands grazing permits who: (1) Have a current HPL grazing permit, or have had an HPL permit issued since 1980, or are current HPL residents and can show documentation of a past grazing permit issued in their...

2011-04-01

317

25 CFR 700.709 - Grazing privileges.  

Code of Federal Regulations, 2010 CFR

...of individuals eligible for New Lands grazing permits who: (1) Have a current HPL grazing permit, or have had an HPL permit issued since 1980, or are current HPL residents and can show documentation of a past grazing permit issued in their...

2010-04-01

318

Influence Of Fall Grazing By Sheep On Plant Productivity, Shrub Age Class Structure And Herbaceous Species Diversity In Sagebrush Steppe.  

E-print Network

??Managing Wyoming Big Sagebrush (Artemisia tridentata ssp. wyomingensis) systems biologically with grazing can potentially reduce costs and increase both biodiversity and understory production as well… (more)

Woodland, Ryan Duncan

2004-01-01

319

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

320

Near anastigmatic grazing incidence telescope  

Microsoft Academic Search

A performance capability assessment is presently conducted for short versus long grazing incidence telescope designs, in view of the observation that the field curvature and astigmatism that are the primary residual aberrations of a Wolter-type incidence telescope can be substantially reduced through mirror length reduction. A major advantage of the short element telescope is that, if sufficiently short, both the

D. Korsch

1984-01-01

321

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

322

Contribution of family labour to the profitability and competitiveness of small-scale dairy production systems in central Mexico.  

PubMed

The objective of this work was to determine the effect of family labour on the profitability and competitiveness of small-scale dairy farms in the highlands of Central Mexico. Economic data from 37 farms were analysed from a stratified statistical sampling with a Neyman assignment. Three strata were defined taking herd size as criterion. Stratum 1: herds from 3 to 9 cows plus replacements, Stratum 2: herds from 10 to 19 cows and Stratum 3: herds from 20 to 30 cows. The policy analysis matrix was used as the method to determine profitability and competitiveness. The coefficient of private profitability (CPP) when the economic cost of family labour is included in the cost structure was 8.0 %, 31.0 % and 46.0 %. When the economic cost of family labour is not included, CPP increase to 47.0 %, 57.0 % and 66.0 % for each strata, respectively. The private cost ratio (PCR) when family labour is included was 0.79, 0.51 and 0.42 for strata 1, 2 and 3, respectively. When family labour is not included, the PCR was 0.07, 0.25 and 0.26. Net profit per litre of milk including family labour was US$0.03 l(-1) for Stratum 1, US$0.09 for Stratum 2 and US$0.12 l(-1) for Stratum 3; but increased to $0.12, 0.14 and 0.15, respectively, when the economic cost of family labour is not included. It is concluded that family labour is a crucial factor in the profitability and competitiveness of small-scale dairy production. PMID:24097246

Posadas-Domínguez, Rodolfo Rogelio; Arriaga-Jordán, Carlos Manuel; Martínez-Castañeda, Francisco Ernesto

2014-01-01

323

Effects of Grazing by Estuarine Gammaridean Amphipods on the Microbiota of Allochthonous Detritus †  

PubMed Central

Estuarine gammaridean amphipods grazing at natural population density on detrital microbiota affected the microbial community composition, biomass, and metabolic activity without affecting the physical structure of the leaves. Total microbial biomass estimated by adenosine triphosphate and lipid phosphate or observed by scanning electron microscopy was greater on grazed than on ungrazed detritus. The rates of oxygen consumption, poly-?-hydroxybutyrate synthesis, total lipid biosynthesis, and release of 14CO2 from radioactively prelabeled microbiota were higher on grazed than on ungrazed leaves, indicating stimulation of the metabolic activity of grazed detrital microbes. This was true with rates based either on the dry leaf weight or microbial biomass. Alkaline phosphatase activity was lower in the grazed system, consistent with enhanced inorganic phosphate cycling. The loss of 14C from both total lipid and poly-?-hydroxybutyrate of microorganisms prelabeled with 14C was greater from grazed than ungrazed microbes. There was a faster decrease in the 14C-glycolipid than in the 14C-neutral lipid or 14C-phospholipid fractions. Analysis of specific phospholipids showed losses of the metabolically stable [14C]glycerolphosphorylcholine derived from phosphatidylcholine and much more rapid metabolism of the bacterial lipid phosphatidylglycerol measured as [14C]glycerolphosphorylglycerol with amphipod grazing. The biochemical data supported scanning electron microscopy observations of a shift as the grazing proceeded from a bacterial/fungal community to one dominated by bacteria. Images PMID:16345641

Morrison, Susan J.; White, David C.

1980-01-01

324

Microwave backscatter from the sea surface at grazing incidence  

Microsoft Academic Search

As part of the Sea Truth and Radar Systems '94 experiment on the Grand Banks of Newfoundland in December, 1994, the authors collected high resolution digital images of radar backscatter from the sea surface at low grazing angle incidence. Analysis of these images and other data collected concurrently allowed validation of certain theories of formation of the two chief components

Joseph R. Buckley; Ryan S. Johnson

1996-01-01

325

Tools to Study and Manage Grazing Behavior at Multiple  

E-print Network

foster low stress animal handling. - Use tools that capitalize on innate animal behavior. #12;BackgroundTools to Study and Manage Grazing Behavior at Multiple Scales to Enhance the Sustainability of Livestock Production Systems By Dean M. Anderson Research Animal Scientist USDA-ARS Jornada Experimental

326

Contamination of grazing incidence EUV mirrors - an assessment  

Microsoft Academic Search

Contamination assessment for space optical systems requires an understanding of the sensitivity of component performance, e.g. mirror reflectance, to materials deposited on the mirror surface. In a previous study, the sensitivity of typical normal incidence mirror coatings to surface deposits of generic hydrocarbons was reported. Recent activity in the development of grazing incidence telescopes for extreme ultraviolet space astronomy has

John F. Osantowski; C. F. Fleetwood

1988-01-01

327

WILDLIFE CONSIDERATIONS IN SEASONAL GRAZING OF RIPARIAN ZONES  

E-print Network

-39 WILDLIFE CONSIDERATIONS IN SEASONAL GRAZING OF RIPARIAN ZONES by Fritz L. Knopf* A riparian and more xeric uplands. Riparian systems have been referred to as the "aortas of ecosystems" because, riparian vegetation usually occurs as narrow belts, or zones, of vegetation along streams and rivers from

328

Effect of different feeding strategies in intensive dairy farming systems on milk fatty acid profiles, and implications on feeding costs in Italy.  

PubMed

The aim of this work was to characterize the fatty acid (FA) profile of milk from intensive dairy farming systems in the Po Plain (Italy) to estimate the costs of the adopted feeding strategies and to simulate the effect of supplementary premiums on the basis of milk FA composition on milk income. Twenty dairy farms with 5 different feeding strategies were studied: 3 corn silage-based systems in which cows were supplemented with a great proportion (CCH), a medium proportion (CCM), or without commercial concentrate mix (CC0), and 2 systems in which part of corn silage was replaced with grass or legume silage (HF) or with fresh herbage (G), cut and fed indoors. Bulk milk was sampled and lactating cow performance, feeding strategies and forage characteristics were recorded through a survey, 3 times during a year. The milk FA supplementary premium was calculated considering C18:3n-3 and saturated FA (SFA) concentrations, and ratio of total cis C18:1 isomers to C16:0. The CCH, CCM, and CC0 systems bought most of their dairy cow feeds off farm, which allowed them to increase milk production to 35,000 L/yr per hectare. Their low dry matter and crude protein self-sufficiency led to higher feeding costs per liter of milk (from €0.158 to €0.184), and highest income over feed cost was achieved only for milk yield performance greater than 10,000 kg/cow per year. The use of homegrown forages in HF and G increased dry matter and crude protein self-sufficiency and reduced the feeding costs per liter of milk from 9 to 22%, compared with the other studied systems, making HF and G feeding economically competitive, even for a lower milk yield per cow. The studied systems highlighted a remarkable variation in FA profiles. The concentrations of C16:0 and SFA were the highest in CCH (31.53 and 67.84 g/100g of FA) and G (31.23 and 68.45 g/100g of FA), because of the larger proportion of commercial concentrate mix in the cow diet. The concentrations of C16:0 and SFA were the lowest in CCM (27.86 and 63.10 g/100g of FA), because of low roughage-to-concentrate ratio in the cow diet, which is known to favor milk fat depression, affecting particularly these FA. The calculated supplementary premium was the highest in the CCM system, based on milk FA profiles from those herds. The HF diet was rich in forages and resulted in greater concentration of C18:3n-3 in milk (0.57 g/100g of FA) than the other systems and thus led to an increase in milk FA supplementary premium. Milk from G and HF milk had the lowest ratio of ?n-6:?n-3 FA compared with milk from the systems based on higher corn silage proportion in the cow diet (3.71, and 3.25, respectively, vs. 4.58 to 4.78), with the lower ratios being closer to recommendation for human nutrition. PMID:24011944

Borreani, G; Coppa, M; Revello-Chion, A; Comino, L; Giaccone, D; Ferlay, A; Tabacco, E

2013-11-01

329

Fertility of dairy cows in Northern Ireland  

Microsoft Academic Search

A comprehensive database was established on the milk production and reproductive performance of dairy cows in 19 selected herds in Northern Ireland, varying in size, management system and genetic merit. Data were obtained for 2471 cows, 1775 of which calved in a second year, and 693 were culled from the herd for specific reasons. The estimated mean rate of heat

C. S. Mayne; D. R. Mackey; M. Verner; W. J. McCaughey; F. J. Gordon; M. A. McCoy; S. D. Lennox; D. C. Catney; A. R. G. Wylie; B. W. Kennedy

2002-01-01

330

Adaptability of Membranes for Dairy Waste Management  

Microsoft Academic Search

Membranes produce a higher quality effluent than achieved using conventional filtration as a final polishing step in dairy Industry. Designed to simplify wastewater treatment, the membrane process replaces secondary clarifiers. Membranes are immersed directly in the bioreactor and operate at high levels of MLVSS (12,000-15,000 ppm) resulting in plant footprints up to 4 times smaller than conventional systems. This treatment

A. S. Khojare; A. B. Kadu; P. G. Wasnik; M. R. Patil; B. A. Khojare

2005-01-01

331

BACTERIAL AND CHEMICAL COMPOSITION OF DAIRY WASTEWATER  

Technology Transfer Automated Retrieval System (TEKTRAN)

High intensity dairy farms produce large amounts of liquid waste that is stored in waste water holding lagoons. The use of circulators to treat waste water is becoming common, and vendors claim that these systems reduce odors, pathogen levels, and alter the chemistry of the waste water such that it ...

332

Response of Organic and Inorganic Carbon and Nitrogen to Long-Term Grazing of the Shortgrass Steppe  

Microsoft Academic Search

We investigated the influence of long-term (56 years) grazing on organic and inorganic carbon (C) and nitrogen (N) contents of the plant–soil system (to 90 cm depth) in shortgrass steppe of northeastern Colorado. Grazing treatments included continuous season-long (May–October) grazing by yearling heifers at heavy (60–75% utilization) and light (20–35% utilization) stocking rates, and nongrazed exclosures. The heavy stocking rate

Jean D. Reeder; Gerald E. Schuman; Jack A. Morgan; Daniel R. LeCain

2004-01-01

333

Near anastigmatic grazing incidence telescope  

NASA Technical Reports Server (NTRS)

A performance capability assessment is presently conducted for short versus long grazing incidence telescope designs, in view of the observation that the field curvature and astigmatism that are the primary residual aberrations of a Wolter-type incidence telescope can be substantially reduced through mirror length reduction. A major advantage of the short element telescope is that, if sufficiently short, both the paraboloid and hyperboloid surfaces may be fabricated as a single piece; this significantly facilitates the task of alignment.

Korsch, D.

1984-01-01

334

DEVELOPMENT OF A STOCHASTIC SIMULATION MODEL TO ASSESS THE POTENTIAL ECONOMIC BENEFITS ASSOCIATED WITH INVESTMENTS IN PRECISION DAIRY FARMING TECHNOLOGIES  

Technology Transfer Automated Retrieval System (TEKTRAN)

A dynamic, stochastic, mechanistic simulation model of a modern dairy enterprise was developed to evaluate the costs and benefits associated with investments in Precision Dairy Farming (PDF) technologies. The model was designed to represent the biological and economic complexities of a dairy system ...

335

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

336

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.

337

Weed selection by sheep grazing dryland lucerne  

Microsoft Academic Search

Diet selection by sheep grazing dryland lucerne with a high proportion of weeds was assessed in two consecutive years (2005\\/2006). The study was performed on 2.66 ha of pasture divided in two homogeneous paddocks subjected to a stocking rate of either 10 or 20 sheep\\/paddock, and grazed for 17 days. Before and after each grazing trial, an inventory was conducted

E. Pérez; A. de Vega; I. Delgado; Y. Pueyo

338

Track way distance and cover as risk factors for lameness in Danish dairy cows.  

PubMed

This study investigates the effect of length and cover of track ways between barn and pasture on lameness in Danish dairy cows. We hypothesised that short track distances would be associated with a lower lameness probability of dairy cows compared to longer distances and that track ways with prepared cover (asphalt, gravel, slag, concrete, rubber) compared to no prepared cover (sand, soil and/or grass) would be associated with a lower lameness probability of dairy cows in grazing herds. In total, 2084 dairy cows from 36 herds, grazing their dairy cows during summer, were individually assessed for their lameness status. The cows were further clinically examined for claw conformation and hock integument. Information on breed and parity per cow and size per herd was extracted from a national data base. Track way distance ranged from 0 to 700 m and was categorised as (1) <165 m or (2) ?165 m. Cover of track way was categorised as (1) prepared (asphalt, gravel, slag, concrete, and/or rubber), (2) partly prepared or (3) not prepared (soil, sand, grass) for the surface of the majority of tracks used. The effect of track way distance and cover was evaluated for their impact on lameness using logistic analysis with a multi-level model structure. The probability for lameness did not change with track distance but increased with no (odds 4.0 times higher) or only partly prepared (odds 3.8 times higher) cover compared to prepared cover. In conclusion, we found that having a cover on the track way was associated with decreased severe lameness in Danish dairy cows. PMID:24387936

Burow, E; Thomsen, P T; Rousing, T; Sørensen, J T

2014-03-01

339

Ruminal environment and forage ruminal digestion in milking cows under grazing and zero-grazing  

E-print Network

Ruminal environment and forage ruminal digestion in milking cows under grazing and zero-grazing ML. A trial was run to study the effect of zero grazing on rumen environment and protein and fiber digestion % crude protein (CP), 55 % neutral detergent fiber (NDF) and 65 % in-vitro digestibility. Treatments were

Paris-Sud XI, Université de

340

Methane emissions from beef cattle grazing on semi-natural upland and improved lowland grasslands.  

PubMed

In ruminants, methane (CH4) is a by-product of digestion and contributes significantly to the greenhouse gas emissions attributed to agriculture. Grazed grass is a relatively cheap and nutritious feed but herbage species and nutritional quality vary between pastures, with management, land type and season all potentially impacting on animal performance and CH4 production. The objective of this study was to evaluate performance and compare CH4 emissions from cattle of dairy and beef origin grazing two grassland ecosystems: lowland improved grassland (LG) and upland semi-natural grassland (UG). Forty-eight spring-born beef cattle (24 Holstein-Friesian steers, 14 Charolais crossbred steers and 10 Charolais crossbred heifers of 407 (s.d. 29), 469 (s.d. 36) and 422 (s.d. 50) kg BW, respectively), were distributed across two balanced groups that grazed the UG and LG sites from 1 June to 29 September at stocking rates (number of animals per hectare) of 1.4 and 6.7, respectively. Methane emissions and feed dry matter (DM) intake were estimated by the SF6 tracer and n-alkane techniques, respectively, and BW was recorded across three experimental periods that reflected the progression of the grazing season. Overall, cattle grazed on UG had significantly lower (P<0.001) mean daily DM intake (8.68 v. 9.55 kg/day), CH4 emissions (176 v. 202 g/day) and BW gain (BWG; 0.73 v. 1.08 kg/day) than the cattle grazed on LG but there was no difference (P>0.05) in CH4 emissions per unit of feed intake when expressed either on a DM basis (20.7 and 21.6 g CH4 per kg DM intake for UG and LG, respectively) or as a percentage of the gross energy intake (6.0% v. 6.5% for UG and LG, respectively). However, cattle grazing UG had significantly (P<0.001) greater mean daily CH4 emissions than those grazing LG when expressed relative to BWG (261 v. 197 g CH4/kg, respectively). The greater DM intake and BWG of cattle grazing LG than UG reflected the poorer nutritive value of the UG grassland. Although absolute rates of CH4 emissions (g/day) were lower from cattle grazing UG than LG, cattle grazing UG would be expected to take longer to reach an acceptable finishing weight, thereby potentially off-setting this apparent advantage. Methane emissions constitute an adverse environmental impact of grazing by cattle but the contribution of cattle to ecosystem management (i.e. promoting biodiversity) should also be considered when evaluating the usefulness of different breeds for grazing semi-natural or unimproved grassland. PMID:25167210

Richmond, A S; Wylie, A R G; Laidlaw, A S; Lively, F O

2015-01-01

341

Cooling dairy cattle by a combination of sprinkling and forced ventilation and its implementation in the shelter system.  

PubMed

A method for cooling dairy cattle based on repeated wetting to attain maximal water trapping in the coat, followed 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 sprinklers. Also examined was the extent to which the diurnal increase in rectal temperature can be prevented. The maximal decrement of temperature was attained at 30 min after cessation of cooling in all trials. Wetting the coat for 10 s was less effective than for 20 or 30 s; the latter did not differ in their effects. Cooling animals for 15, 30, and 45 min produced decrements in temperature of .6, .7, and 1.0 degrees C, respectively. Maintaining animals at a density of 1.9 m2/cow in the holding area reduced to about half the decrement as compared with a density of 3.5 m2/cow. When cows were cooled 5 times per day for 30 min, temperatures were maintained within 38.2 to 38.9 degrees C during the day, which were significantly lower than for those not cooled. PMID:3558927

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

1986-12-01

342

TILLAGE AND GRAZING EFFECTS ON SOIL PHYSICAL PROPERTIES AND CROP YIELD  

Technology Transfer Automated Retrieval System (TEKTRAN)

Water conservation using deficit irrigation and dryland cropping systems are being implemented where the Ogallala aquifer limits irrigation capacity. Decreased crop productivity and profitability has encouraged integration of cattle grazing to supplement crop income, but potential soil compaction ma...

343

Sheepdogs and Barbed Wire: An Environmental History of Grazing on the High Plains  

E-print Network

An environmental history of High Plains grazing that focused on transhumant sheepherding of New Mexico, watershed cattle ranching of the open range, and barbed-wire stock-farming of the privatized plains--all systems of ...

Kerr, Daniel Stewart

2010-05-31

344

25 CFR 167.11 - Tenure of grazing permits.  

Code of Federal Regulations, 2010 CFR

...permit as defined in § 167.8 may become a livestock operator by obtaining an active grazing permit through negotiability or inheritance or both. (b) In many Districts, and portions of all districts, unused grazing permits or portions of grazing...

2010-04-01

345

25 CFR 167.11 - Tenure of grazing permits.  

Code of Federal Regulations, 2013 CFR

...permit as defined in § 167.8 may become a livestock operator by obtaining an active grazing permit through negotiability or inheritance or both. (b) In many Districts, and portions of all districts, unused grazing permits or portions of grazing...

2013-04-01

346

Dairy methane generator. Final report  

SciTech Connect

Details of the work completed under this contract are presented. During the winter of 1979-80 three students enrolled, in the Mechanical Design Engineering Technology program at the Pennsylvania State University's Capitol Campus (Middletown, PA), undertook a feasibility study for the utilization of the manure generated by the dairy cows located on Mr. Thomas B. Williams farm for the generation and use of methane gas. The results of their effort was the design of an Anaerobic Digester/Electric Generation System. This preliminary designed system was later changed and improved by another group of P.S.U. MDET students in the spring of 1980. The final design included working drawings and an economic analysis of the estimated investment necessary to complete the Methane Generator/Electric Power Generation System.

Williams, T.B.

1981-09-30

347

Standing crop dynamics under simulated short-duration grazing at four stocking rates  

E-print Network

been attributed to rotational grazing. Short-Duration Grazing SDG became popular in Rhodesia during the 1960's (Goodloe 1969) and later became known as the "Savory System" (Ian de la Rue 1975). Interest in SDG increased markedly in the U. S. during... 60 days. This length of rest periods was also recommended by Savory (1976). HILP has grazing periods greater than 2 weeks and rest periods longer than 60 days. It has been claimed that heavier stocking rates can be used under SDG than under...

Casco, Jose Francisco

1984-01-01

348

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

349

Freeze concentration of dairy products Phase 2. Final report  

SciTech Connect

An efficient, electrically driven freeze concentration system offers potential for substantially increasing electricity demand while providing the mature dairy industry with new products for domestic and export markets together with enhanced production efficiencies. Consumer tests indicate that dairy products manufactured from freeze-concentrated ingredients are either preferred or considered equivalent in quality to fresh milk-based products. Economic analyses indicate that this technology should be competitive with thermal evaporation processes on a commercial basis.

Best, D.E.; Vasavada, K.C.

1993-09-01

350

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

351

Grazed Riparian Management and Stream Channel Response in Southeastern Minnesota (USA) Streams  

NASA Astrophysics Data System (ADS)

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.

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

2008-09-01

352

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

353

Mycobacterium tuberculosis infection in grazing cattle in central Ethiopia  

PubMed Central

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

2011-01-01

354

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

355

Extending the Grazing Season for Beef Cattle  

Microsoft Academic Search

Snow depth, ice encasement, and extremely high moisture should be the only conditions that limit our ability to graze. While forage conservation is a necessity given Minnesota's winters, every additional day of grazing saves money and thus increases potential for profit to the beef operation. We must recognize that the \\

Paul Peterson; Av Singh; Russ Mathison; Craig Sheaffer; Nancy Ehlke; Greg Cuomo

356

25 CFR 167.8 - Grazing rights.  

Code of Federal Regulations, 2013 CFR

...167.7 or who have acquired grazing rights by marriage, inheritance, purchase or division of permits. Whenever the permitted...of age can get possession of grazing permits only through inheritance or gift, and in each case Trustees must be appointed...

2013-04-01

357

25 CFR 167.8 - Grazing rights.  

Code of Federal Regulations, 2010 CFR

...167.7 or who have acquired grazing rights by marriage, inheritance, purchase or division of permits. Whenever the permitted...of age can get possession of grazing permits only through inheritance or gift, and in each case Trustees must be appointed...

2010-04-01

358

25 CFR 167.8 - Grazing rights.  

Code of Federal Regulations, 2011 CFR

...167.7 or who have acquired grazing rights by marriage, inheritance, purchase or division of permits. Whenever the permitted...of age can get possession of grazing permits only through inheritance or gift, and in each case Trustees must be appointed...

2011-04-01

359

25 CFR 167.8 - Grazing rights.  

Code of Federal Regulations, 2014 CFR

...167.7 or who have acquired grazing rights by marriage, inheritance, purchase or division of permits. Whenever the permitted...of age can get possession of grazing permits only through inheritance or gift, and in each case Trustees must be appointed...

2014-04-01

360

25 CFR 167.8 - Grazing rights.  

Code of Federal Regulations, 2012 CFR

...167.7 or who have acquired grazing rights by marriage, inheritance, purchase or division of permits. Whenever the permitted...of age can get possession of grazing permits only through inheritance or gift, and in each case Trustees must be appointed...

2012-04-01

361

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

362

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

363

Response of carbon dioxide emissions to sheep grazing and N application in an alpine grassland - Part 1: Effect of sheep grazing  

NASA Astrophysics Data System (ADS)

Previous work has failed to address fully the response of (autotrophic and heterotrophic) respiration to grazing in different ecosystems, particularly in alpine grasslands outside the growing season. From 2010 to 2011 a field experiment combined two methods (static closed chambers and a closed dynamic soil CO2 flux system) in alpine grasslands located in the Tianshan Mountains. We examined the effects of grazing regime on ecosystem respiration (Re) both outside (NGS) and during (GS) the growing season and determined the pattern of Re in relation to climate change. There was no significant change in CO2 emissions under grazing. Heterotrophic respiration (Rh) accounted for 78.5% of Re with short-term grazing exclusion and 93.2% of Re with long-term grazing exclusion. Re, Rh and autotrophic respiration (Ra) fluxes outside the growing season were equivalent to 12.9%, 14.1% and 11.4% of the respective CO2 fluxes during the growing season. In addition, our results indicate that soil water content played a critical role in Ra in the cold and arid environment. Both Rh and Re were sensitive to soil temperature. Moreover, our results suggest that grazing exerted no significant effect on CO2 emissions in these alpine grasslands.

Gong, Y. M.; Mohammat, A.; Liu, X. J.; Li, K. H.; Christie, P.; Fang, F.; Song, W.; Chang, Y. H.; Han, W. X.; Lü, X. T.; Liu, Y. Y.; Hu, Y. K.

2014-04-01

364

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 Central

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

2014-01-01

365

Effect of rumen-undegradable protein supplementation and fresh forage composition on nitrogen utilization of dairy ewes.  

PubMed

Previous trials with dairy ewes fed stored feeds indicate a positive effect of rumen-undegradable protein (RUP) supplementation on milk yield. However, dairy sheep production in the United States is primarily based on grazing mixed grass-legume pastures, which contain a high proportion of rumen-degradable protein. Two trials were conducted to evaluate the effects of high-RUP protein supplementation and fresh forage composition on milk yield and N utilization of lactating dairy ewes fed in confinement or on pasture. In a cut-and-carry trial, 16 multiparous dairy ewes in mid-lactation were randomly assigned to 8 pens of 2 ewes each. Pens were randomly assigned 1 of 2 protein supplementation treatments, receiving either 0.0 or 0.3 kg of a high-RUP protein supplement (Soy Pass, LignoTech USA Inc., Rothschild, WI) per day. Within supplementation treatment, pens were randomly assigned to 1 of 4 forage treatments, which were applied in a 4×4 Latin square design for 10-d periods. Forage treatments included the following percentages of orchardgrass:alfalfa dry matter: 25:75, 50:50, 75:25, and 100:0. No interactions were observed between supplement and forage treatments. Supplementation with a high-RUP source tended to increase milk yield by 9%. Milk yield, milk protein yield, milk urea N, and urinary urea N excretion increased linearly with increased percentage of alfalfa. Milk N efficiency was greatest on the 100% orchardgrass diet. In a grazing trial, 12 multiparous dairy ewes in mid lactation were randomly assigned to 3 groups of 4 ewes each. Within group, 2 ewes were randomly assigned to receive either 0.0 or 0.3 kg of a high-RUP protein supplement (SoyPlus, West Central Cooperative, Ralston, IA) per day. Grazing treatments were arranged in a 3×3 Latin square design and applied to groups for 10-d periods. Ewes grazed paddocks that contained the following percentages of surface area of pure stands of orchardgrass:alfalfa: 50:50, 75:25, and 100:0. No interactions were found between supplement and forage treatments. Milk yield, milk protein yield, and milk urea N increased linearly with increased percentage of alfalfa in the paddock. In conclusion, supplementing with high-RUP protein tended to increase milk yield and increasing the proportion of alfalfa in the diet increased dry matter intake, milk yield, and protein yield of lactating dairy ewes fed or grazing fresh forage. PMID:21183052

Mikolayunas, C; Thomas, D L; Armentano, L E; Berger, Y M

2011-01-01

366

Epidemiology and effects of gastrointestinal nematode infection on milk productions of dairy ewes.  

PubMed

66 Pampinta breed ewes were studied during milking to evaluate the infection and the effect of gastrointestinal nematode on milk production sheep system. Naturally infected ewes on pasture were randomly allocated to two groups: TG, suppressively treated group every four weeks with levamisole and UG, untreated group. Faecal nematode egg counts and larval differentiation were conducted monthly. Successive groups of worm free tracer lambs were grazed with ewes and then slaughtered for worm counts. Test-day milk yield of individual ewes was recorded and ewe machine-milking period length (MPL) were estimated. Faecal egg counts and tracer nematode numbers increased towards midsummer and declined sharply toward the end of the study. TG (188.0 +/- 60 liters) produced more (p < 0.066) milk liters than UG (171.9 +/- 52.2) and TG had significantly more extended (p < 0.041) MPL than those of UG. The present study showed that dairy sheep were negatively affected by worms, even when exposed to short periods of high acute nematode (mainly Haemonchus contortus) infection. PMID:19585893

Suarez, V H; Cristel, S L; Busetti, M R

2009-06-01

367

Design of stigmatic grazing incidence telescopes with non-parabolic primaries  

Microsoft Academic Search

A two-mirror grazing-incidence telescope having a non-parabolic primary, and designed to be free of spherical aberration has been investigated. A method for determining the second surface equation is described, when the surface equation for one mirror is given. Application to grazing incidence systems such as used in X-ray and planed for EUV astronomy is discussed. Of special interest is the

C. E. Winkler; D. Korsch

1979-01-01

368

Livestock Production and Economic Returns from Grazing Treatments on the Texas Experimental Ranch.  

E-print Network

of winter supplementation was mined. The stocking rates studied were heavy, moder- nd light which were designed to utilize 75 to 80 nt, 45 to 50 percent and 20 to 30 percent of the nt year's forage production. Three grazing systems, ~uous grazing... pounds from heavy to moderate and from moderate to light stocking, respectively, while calf weaning weights increased only 11 and 5 pounds from heavy to moderate and from moderate to light stocking, respectively. Decreasing stock- ing rates did...

Kothmann, M. M.; Mathis, G. W.; Marion, P. T.; Waldrip, W. J.

1970-01-01

369

Dairy goat demography and Q fever infection dynamics  

PubMed Central

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

2013-01-01

370

Multilayer and grazing incidence X-ray\\/EUV optics for astronomy and projection lithography; Proceedings of the Meeting, San Diego, CA, July 19-22, 1992  

Microsoft Academic Search

The present volume on multilayer and grazing incidence X-ray\\/EUV optics for astronomy and projection lithography discusses AXAF grazing incidence mirrors, the theory and high throughput optics of grazing incidence optics, multilayer mirror fabrication and characterization, and multilayer optics for X-ray projection lithography. Attention is given to the VETA-I X-ray detection system, a motion detection system for AXAF X-ray ground testing,

Richard B. Hoover; Arthur B. C. Walker Jr.

1993-01-01

371

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. PMID:9546161

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

1998-01-01

372

Rabbit grazing and species diversity in a dune area  

Microsoft Academic Search

Summary The relation between density of rabbit populations and plant species diversity is discussed. In the dunes of the Dutch Frisian Island of Schiermonnikoog, the rabbit grazing pressure has been quantified on the basis of traces of recent grazing activity. Moderate grazing turned out to bring about maximal species richness. Current changes in grazing pressure (either decrease or increase) can

H. J. Zeevalking; L. F. M. Fresco

1977-01-01

373

Effects of fencing, alternative water, grazing management & other ag BMPs  

E-print Network

Management #12;E. coli not correlated w/ grazing mgt. (in rotationally grazed pastures) #12;E. coli 100 1000 E. coli Conc. (cfu/100 mL) 12 Month Stocking Rate (ac/AUY) Ungrazed #12;E. coli correlated w at BB3 99% reduction at SW17 #12;Effect of grazing management on E. coli levels in rotationally grazed

374

Response of organic and inorganic carbon and nitrogen to long-term grazing of the shortgrass steppe.  

PubMed

We investigated the influence of long-term (56 years) grazing on organic and inorganic carbon (C) and nitrogen (N) contents of the plant-soil system (to 90 cm depth) in shortgrass steppe of northeastern Colorado. Grazing treatments included continuous season-long (May-October) grazing by yearling heifers at heavy (60-75% utilization) and light (20-35% utilization) stocking rates, and nongrazed exclosures. The heavy stocking rate resulted in a plant community that was dominated (75% of biomass production) by the C4 grass blue grama (Bouteloua gracilis), whereas excluding livestock grazing increased the production of C3 grasses and prickly pear cactus (Opuntia polycantha). Soil organic C (SOC) and organic N were not significantly different between the light grazing and nongrazed treatments, whereas the heavy grazing treatment was 7.5 Mg ha(-1) higher in SOC than the nongrazed treatment. Lower ratios of net mineralized N to total organic N in both grazed compared to nongrazed treatments suggest that long-term grazing decreased the readily mineralizable fraction of soil organic matter. Heavy grazing affected soil inorganic C (SIC) more than the SOC. The heavy grazing treatment was 23.8 Mg ha(-1) higher in total soil C (0-90 cm) than the nongrazed treatment, with 68% (16.3 Mg ha(-1)) attributable to higher SIC, and 32% (7.5 Mg ha(-1)) to higher SOC. These results emphasize the importance in semiarid and arid ecosystems of including inorganic C in assessments of the mass and distribution of plant-soil C and in evaluations of the impacts of grazing management on C sequestration. PMID:15453402

Reeder, Jean D; Schuman, Gerald E; Morgan, Jack A; Lecain, Daniel R

2004-04-01

375

Eaten Out of House and Home: Impacts of Grazing on Ground-Dwelling Reptiles in Australian Grasslands and Grassy Woodlands  

PubMed Central

Large mammalian grazers can alter the biotic and abiotic features of their environment through their impacts on vegetation. Grazing at moderate intensity has been recommended for biodiversity conservation. Few studies, however, have empirically tested the benefits of moderate grazing intensity in systems dominated by native grazers. Here we investigated the relationship between (1) density of native eastern grey kangaroos, Macropus giganteus, and grass structure, and (2) grass structure and reptiles (i.e. abundance, richness, diversity and occurrence) across 18 grassland and grassy Eucalyptus woodland properties in south-eastern Australia. There was a strong negative relationship between kangaroo density and grass structure after controlling for tree canopy cover. We therefore used grass structure as a surrogate for grazing intensity. Changes in grazing intensity (i.e. grass structure) significantly affected reptile abundance, reptile species richness, reptile species diversity, and the occurrence of several ground-dwelling reptiles. Reptile abundance, species richness and diversity were highest where grazing intensity was low. Importantly, no species of reptile was more likely to occur at high grazing intensities. Legless lizards (Delma impar, D. inornata) were more likely to be detected in areas subject to moderate grazing intensity, whereas one species (Hemiergis talbingoensis) was less likely to be detected in areas subject to intense grazing and three species (Menetia greyii, Morethia boulengeri, and Lampropholis delicata) did not appear to be affected by grazing intensity. Our data indicate that to maximize reptile abundance, species richness, species diversity, and occurrence of several individual species of reptile, managers will need to subject different areas of the landscape to moderate and low grazing intensities and limit the occurrence and extent of high grazing. PMID:25501680

Howland, Brett; Stojanovic, Dejan; Gordon, Iain J.; Manning, Adrian D.; Fletcher, Don; Lindenmayer, David B.

2014-01-01

376

Eaten out of house and home: impacts of grazing on ground-dwelling reptiles in Australian grasslands and grassy woodlands.  

PubMed

Large mammalian grazers can alter the biotic and abiotic features of their environment through their impacts on vegetation. Grazing at moderate intensity has been recommended for biodiversity conservation. Few studies, however, have empirically tested the benefits of moderate grazing intensity in systems dominated by native grazers. Here we investigated the relationship between (1) density of native eastern grey kangaroos, Macropus giganteus, and grass structure, and (2) grass structure and reptiles (i.e. abundance, richness, diversity and occurrence) across 18 grassland and grassy Eucalyptus woodland properties in south-eastern Australia. There was a strong negative relationship between kangaroo density and grass structure after controlling for tree canopy cover. We therefore used grass structure as a surrogate for grazing intensity. Changes in grazing intensity (i.e. grass structure) significantly affected reptile abundance, reptile species richness, reptile species diversity, and the occurrence of several ground-dwelling reptiles. Reptile abundance, species richness and diversity were highest where grazing intensity was low. Importantly, no species of reptile was more likely to occur at high grazing intensities. Legless lizards (Delma impar, D. inornata) were more likely to be detected in areas subject to moderate grazing intensity, whereas one species (Hemiergis talbingoensis) was less likely to be detected in areas subject to intense grazing and three species (Menetia greyii, Morethia boulengeri, and Lampropholis delicata) did not appear to be affected by grazing intensity. Our data indicate that to maximize reptile abundance, species richness, species diversity, and occurrence of several individual species of reptile, managers will need to subject different areas of the landscape to moderate and low grazing intensities and limit the occurrence and extent of high grazing. PMID:25501680

Howland, Brett; Stojanovic, Dejan; Gordon, Iain J; Manning, Adrian D; Fletcher, Don; Lindenmayer, David B

2014-01-01

377

Grazing incidence optics in extreme-ultraviolet astronomy  

Microsoft Academic Search

The development of grazing incidence optics for extreme ultraviolet (EUV) astronomy occurred in a vastly different science-political environment than that of x-ray astronomy. X- ray astronomy had been proven as an extremely useful field of research, and in the environment of the 1960s funds were available for x-ray glass mirror systems costing tens of millions of dollars for a single

C. Stuart Bowyer

1995-01-01

378

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

379

Authenticity Assessment of Dairy Products  

Microsoft Academic Search

The authenticity of dairy products has become a focal point, attracting the attention of scientists, producers, consumers, and policymakers. Among many others, some of the practices not allowed in milk and milk products are the substitution of part of the fat or proteins, admixtures of milk of different species, additions of low-cost dairy products (mainly whey derivatives), or mislabeling of

Miguel Angel De La Fuente; Manuela Juárez

2005-01-01

380

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

381

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

382

New Hampshire Dairy Goat Seminar Milk Sanitation  

E-print Network

New Hampshire Dairy Goat Seminar Milk Sanitation Farm and Forest Exposition Saturday-February 8 Phil Cassette, President, American Dairy Goat Association; and District #1 Directors: Jennifer Mellett the conference and 4-H dairy goat activities. Dairy Goat publications will also be for sale. John C. Porter

New Hampshire, University of

383

Current Issues in the Stabilization of Cultured Dairy Products  

Microsoft Academic Search

The design of a successful stabilization system for a dairy gel system is dependent on several factors, in- cluding raw materials, existing processing systems, and end user requirements. Raw materials range from natural products that are subject to agricultural variations to customized ingredients that are made to consistent specifications. Processing systems range from well-established methods to the newest technol- ogy.

C. C. Hunt; J. R. Maynes

1997-01-01

384

Lagrangian studies of phytoplankton growth and grazing relationships in a coastal upwelling ecosystem off Southern California  

NASA Astrophysics Data System (ADS)

Experimental studies of phytoplankton growth and grazing processes were conducted in the coastal upwelling system off Point Conception, California to test the hypothesis that phytoplankton growth and grazing losses determine, to first order, the local dynamics of phytoplankton in the upwelling circulation. Eight experiments of 3-5 days each were conducted over the course of two cruises in May-June 2006 and April 2007 following the trajectories of satellite-tracked drifters. Rates of phytoplankton growth and microzooplankton grazing were determined by daily in situ dilution incubations at 8 depths spanning the euphotic zone. Mesozooplankton grazing was assessed by gut fluorescence analysis of animals collected from net tows through the euphotic zone. We compared directly the net rates of change observed for the ambient phytoplankton community to the net growth rates predicted from experimental determinations of each process rate. The resulting relationship accounted for 91% of the variability observed, providing strong support for the growth-grazing hypothesis. In addition, grazing by mesozooplankton was unexpectedly high and variable, driving a substantial positive to negative shift in phytoplankton net rate of change between years despite comparable environmental conditions and similar high growth rates and suggesting strong top-down control potential. The demonstrated agreement between net ambient and experimental community changes is an important point of validation for using field data to parameterize models. Data sets of this type may provide an important source of new information and rate constraints for developing better coupled biological-physical models of upwelling system dynamics.

Landry, Michael R.; Ohman, Mark D.; Goericke, Ralf; Stukel, Michael R.; Tsyrklevich, Kate

2009-12-01

385

The inclusion of a daisy plant ( Chrysanthemum coronarium) in dairy sheep diet. 1: Effect on milk and cheese fatty acid composition with particular reference to C18:2 cis-9, trans-11  

Microsoft Academic Search

An experiment was carried out to evaluate the effect on milk and cheese fatty acid composition of the inclusion of Chrysanthemum coronarium L., (Asteracea) into dairy sheep diet. Plots sown either with a binary mixture consisting of Lolium rigidum Gaudin and Medicago polymorpha (LM) or a ternary mixture including the above species and C. coronarium were (LMC) grazed by groups

A. Cabiddu; M. Addis; G. Pinna; S. Spada; M. Fiori; M. Sitzia; A. Pirisi; G. Piredda; G. Molle

2006-01-01

386

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

PubMed

In the past decade, the demand for organic agricultural products has increased rapidly in the United States and worldwide. Milk quality research is of major interest to both consumers and dairy farmers alike. However, scientific data on milk quality, herd management methods, and animal welfare on organic farms in the United States has been lacking before the research from this study. The objective of this study was to evaluate the association of bulk tank milk somatic cell count (SCC) with management characteristics on organic and conventional dairy farms in New York, Oregon, and Wisconsin. Data from similarly sized organic farms (n=192), conventional nongrazing farms (n=64), and conventional grazing farms (n=36) were collected at a single farm visit. Of the 292 farms visited, 290 bulk tank milk samples were collected. Overall, no difference in SCC was observed between the conventional and organic grazing systems. Two models were created to assess the effects of various management and herd characteristics on the logarithmic transformation of the SCC (LSCC), one using data from all herds and one using data from organic herds only. From the total herd model, more grain fed per cow per day was negatively associated with LSCC, whereas a positive bulk tank culture for Staphylococcus aureus and years that a farmer reported being in the dairy business were both positively associated with LSCC. In the organic herd model, a seasonal effect indicated that LSCC tended to increase in the summer and decrease in the winter. Grain fed per cow per day, the use of anionic salts in transition-cow diets, the use of gloves during milking, and regular use of a quarantine unit at milking were all negatively associated with LSCC. Similar to the total herd model, a Staph. aureus-positive bulk tank culture was positively associated with LSCC in the organic model. Standard plate count was also positively associated with LSCC in the organic model. Several variables that were associated with management using external resources were combined to create an external input score. In the total herd model, use of more external resources was negatively associated with LSCC. Conventional herds in the study tended to use more outside management resources than organic herds. PMID:23548286

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

2013-06-01

387

An experimental analysis of grasshopper community responses to fire and livestock grazing in a northern mixed-grass prairie.  

PubMed

The outcomes of grasshopper responses to both vertebrate grazing and fire vary across grassland ecosystems, and are strongly influenced by local climactic factors. Thus, the possible application of grazing and fire as components of an ecologically based grasshopper management strategy must be investigated in regional studies. In this study, we examined the effects of grazing and fire on grasshopper population density and community composition in a northern Great Plains mixed-grass prairie. We employed a large-scale, replicated, and fully-factorial manipulative experimental design across 4 yr to examine the separate and interactive effects of three grazing systems in burned and unburned habitats. Grasshopper densities were low throughout the 4-yr study and 1 yr of pretreatment sampling. There was a significant fire by grazing interaction effect on cumulative density and community composition, resulting from burned season long grazing pastures having higher densities than unburned pastures. Shannon diversity and grasshopper species richness were significantly higher with twice-over rotational livestock grazing. The ability to draw strong conclusions regarding the nature of species composition shifts and population changes in the presence of fire and grazing is complicated by the large site differences and low grasshopper densities. The results reinforce the importance of long-term research to examine the effects of habitat manipulation on grasshopper population dynamics. PMID:22546438

Branson, David H; Sword, Gregory A

2010-10-01

388

Development of intramammary delivery systems containing lasalocid for the treatment of bovine mastitis: impact of solubility improvement on safety, efficacy, and milk distribution in dairy cattle  

PubMed Central

Background Mastitis is a major disease of dairy cattle. Given the recent emergence of methicillin-resistant Staphylococcus aureus as a cause of bovine mastitis, new intramammary (IMA) treatments are urgently required. Lasalocid, a member of the polyether ionophore class of antimicrobial agents, has not been previously administered to cows by the IMA route and has favorable characteristics for development as a mastitis treatment. This study aimed to develop an IMA drug delivery system (IMDS) of lasalocid for the treatment of bovine mastitis. Methods Minimum inhibitory concentrations (MICs) were determined applying the procedures recommended by the Clinical and Laboratory Standards Institute. Solid dispersions (SDs) of lasalocid were prepared and characterized using differential scanning calorimetry and Fourier transform infrared spectroscopy. IMDSs containing lasalocid of micronized, nano-sized, or as SD form were tested for their IMA safety in cows. Therapeutic efficacy of lasalocid IMDSs was tested in a bovine model involving experimental IMA challenge with the mastitis pathogen Streptococcus uberis. Results Lasalocid demonstrated antimicrobial activity against the major Gram-positive mastitis pathogens including S. aureus (MIC range 0.5–8 ?g/mL). The solubility test confirmed limited, ion-strength-dependent water solubility of lasalocid. A kinetic solubility study showed that SDs effectively enhanced water solubility of lasalocid (21–35-fold). Polyvinylpyrrolidone (PVP)-lasalocid SD caused minimum mammary irritation in treated cows and exhibited faster distribution in milk than either nano or microsized lasalocid. IMDSs with PVP-lasalocid SD provided effective treatment with a higher mastitis clinical and microbiological cure rate (66.7%) compared to cloxacillin (62.5%). Conclusion Lasalocid SD IMDS provided high cure rates and effectiveness in treating bovine mastitis with acceptable safety in treated cows. PMID:25653501

Wang, Wen; Song, Yunmei; Petrovski, Kiro; Eats, Patricia; Trott, Darren J; Wong, Hui San; Page, Stephen W; Perry, Jeanette; Garg, Sanjay

2015-01-01

389

Field Demonstration of the Performance of the L4DB® Microbial Treatment System to Reduce Phosphorus and Other Substances from Dairy Lagoon Effluent  

E-print Network

) was evaluated, which may aid dairy farmers in reducing P from lagoon effluent. In many cases, this effluent is applied to waste application fields (WAFs) as irrigation water; thus reducing P in the effluent can have a direct impact on NPS pollution...

Mukthar, S.; Rahman, S.; Gregory, L.

390

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

391

Grazing management of oversown tussock country  

Microsoft Academic Search

The botanical composition of an oversown tussock pasture on a steep (30°), southeast hillside (760-930 m altitude, 500 mm annual rainfall) was measured each spring for six consecutive seasons under nine grazing management treatments. Continuous stocking, alternating (two paddock), and rotational (six paddock) grazing with merino wether hoggets were each compared at low, medium, and high stocking rates (1.9, 3.0,

B. E. Allan; K. F. OConnor; J. G. H. White

1992-01-01

392

Grazing Management of Temperate Grasslands and Fallows  

E-print Network

44 GRAZING MANAGEMENT OF TEMPERATE GRASSLAND AND FALLOWS Walter Roder* Introduction The paper provides a general overview of fodder resources and their management in temperate Bhutan (altitude range of 1500-3000m). The terms are used... as defined by RC-Jakar (RNR-RC-Jakar, 1996). As per these definitions, temperate pasture can include any kind of land used for grazing. When referring to registered grassland or tsamdro, only the term tsamdrog is used. Where possible, the term pasture...

Roder, Walter

2002-01-01

393

Dairy Futures Information Homepage  

NSDL National Science Digital Library

Provided by Department of Agricultural And Applied Economics Professor T. Randall Fortenberry and Center for Dairy Research Scientist Brian Gould at the University of Wisconsin-Madison, this no-nonsense site is highlighted by its data files section, which contain, at this time, cash and futures data and graphs for the Basic Formula Price, butter, cheese, milk, and nonfat dry milk. Time series vary by commodity and are available in text and three spreadsheet formats. The site also contains other selected price data, and pointers to relevant web sites. Options data is forthcoming.

2005-11-30

394

AMS Dairy Market News  

NSDL National Science Digital Library

The Agricultural Marketing Service of the US Department of Agriculture has made available (Adobe Acrobat [.pdf] format only) this weekly report, which is an indispensible resource for dairy market analysts. It tracks trends in the butter, cheese, fluid milk, nonfat dry milk, whey and casein markets, on a national and regional basis. Though certainly not aimed at the casual reader, this is probably the best place to keep current of market developments. Weekly, monthly, and annual pertinent statistical average tables (mostly prices) are also available.

1997-01-01

395

Grazing incidence telescopes for x-ray astronomy  

NASA Astrophysics Data System (ADS)

With grazing incidence telescopes, x-ray astronomy became a major branch of astrophysics. They are an indispensable tool in the study of >106 K thermal and non-thermal high energy phenomena occurring in objects from the solar system to the most distant sites in the universe. They have shed light upon dark matter and dark energy. Four cosmic missions with focusing grazing incidence x-ray telescopes based upon the Wolter 1 geometry are currently in space. They include two observatory class facilities launched in 1999, NASA's high resolution x-ray and ESA's high throughput XMM-Newton. Two others are Japan's Suzaku, performing a variety of studies, and the Swift XRT, which finds precise positions for the x-ray afterglows of gamma-ray bursts. Four new cosmic missions with Wolter-like focusing telescopes are scheduled for launch. They will provide much broader bandwidth (NuSTAR and Astro-H), perform a new sky survey with more exposure time and a broader energy range than previous surveys (eROSITA), have an imaging detector with much better energy resolution (Astro-H), and measure polarization (GEMS). The Kirkpatrick-Baez and the lobster-eye are two types of potentially useful grazing incidence telescopes that have not yet been in orbit. It may not be possible to improve upon Chandra's 0.5 arcsec resolution without new technology.

Gorenstein, Paul

2012-01-01

396

Corn stubble grazing by steers after mechanical grain harvest 1. Stubble fractions changing through grazing periods  

E-print Network

Corn stubble grazing by steers after mechanical grain harvest 1. Stubble fractions changing through Aires, Argentine Amounts of corn stubble fractions were evaluated at the start of the grazing period, day 1 (T1), at the middle of the period, 28 days (T2), and at 56 days (T3) in the Argentine corn belt

Paris-Sud XI, Université de

397

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

398

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

399

Effects of ventilation rate and of dietary protein level in an intensive dairy sheep system on the features of Canestrato Pugliese cheese.  

PubMed

Effects of ventilation rate and of dietary protein level in an intensive dairy sheep system on the features of Canestrato Pugliese cheese were studied. Cheeses were manufactured from the bulk milk obtained from ewes subjected to four different experimental treatments: (1) low dietary crude protein (CP) of 13% in dry matter (DM) at a low ventilation rate (23.5 m3/h per ewe) (LPLV); (2) low dietary CP at a moderate ventilation rate (47 m3/h per ewe) (LPMV), (3) moderate dietary CP of 16% DM at a low ventilation rate (MPLV); and (4) moderate dietary CP dietary at a moderate ventilation rate (MPMV). Bulk milk and cheeses (at 1, 15, 45 and 90 d of ripening) were analysed for chemical composition, N fractions and plasmin-plasminogen activities. The pH 4.6-soluble and insoluble N fractions were analysed by urea-PAGE. Bulk milk from ewes receiving the low CP diet displayed higher casein and lower urea contents. Ewes subjected to the low ventilation rate displayed a higher plasminogen activity in milk, whereas no differences emerged among treatments in the conversion of zymogen to plasmin. During ripening the plasmin-plasminogen system in cheese did not display significant changes across treatments. At 90 d of ripening, the cheese produced with milk from ewes receiving the low CP diet and exposed to the low ventilation rate displayed more markedly stained bands in the area of gamma-caseins in pH 4.6-insoluble N fraction. As from 15 d of ripening, the pH 4.6-soluble fraction showed a greater number of bands in the LPMV and MPMV than in the LPLV and MPLV cheeses. The results showed that Canestrato Pugliese cheese manufactured with milk from ewes fed the low CP diet and exposed to the moderate ventilation rate was characterized by higher protein and casein content in the fresh cheese and by a greater proteolysis after 90 d of ripening. PMID:16978430

Albenzio, Marzia; Santillo, Antonella; Caroprese, Mariangela; Marino, Rosaria; Annicchiarico, Giovanni; Sevi, Agostino

2007-02-01

400

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

401

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

Federal Register 2010, 2011, 2012, 2013, 2014

...Grazing Allotments for Term Grazing Permit Renewals in the Southern San Luis Valley, CO AGENCY: Bureau of...renewal of domestic sheep grazing permits on 12 allotments and 1 cattle grazing allotment in the southern San Luis Valley. This notice...

2011-06-02

402

Use of Repeated Measures Analysis for Evaluation of Genetic Background of Dairy Cattle Behavior in Automatic Milking Systems  

Microsoft Academic Search

Milking frequencies measured at official test days were used with repeated measurement analysis to re- veal the environmental and genetic impact on the milk- ing frequency of cows in automatic milking systems. Repeated measurements were 3 test-day observations per cow within days in milk (DIM) classes, with 1,216 cows in DIM class 1 (d 0 to 99), from 1,112 cows

S. König; F. Köhn; K. Kuwan; H. Simianer; M. Gauly

2006-01-01

403

Water quality and the grazing animal.  

PubMed

Grazing animals and pasture production can affect water quality both positively and negatively. Good management practices for forage production protect the soil surface from erosion compared with conventionally produced crops. Grazing animals and pasture production can negatively affect water quality through erosion and sediment transport into surface waters, through nutrients from urine and feces dropped by the animals and fertility practices associated with production of high-quality pasture, and through pathogens from the wastes. Erosion and sediment transport is primarily associated with high-density stocking and/or poor forage stands. The two nutrients of primary concern relating to animal production are N and P. Nitrogen is of concern because high concentrations in drinking water in the NO(3) form cause methemoglobinemia (blue baby disease), whereas other forms of N (primarily nitrite, NO(2)) are considered to be potentially carcinogenic. Phosphorus in the PO(4) form is of concern because it causes eutrophication of surface water bodies. The effect of grazing animals on soil and water quality must be evaluated at both the field and watershed scales. Such evaluation must account for both direct input of animal wastes from the grazing animal and also applications of inorganic fertilizers to produce quality pastures. Watershed-scale studies have primarily used the approach of nutrient loadings per land area and nutrient removals as livestock harvests. A number of studies have measured nutrient loads in surface runoff from grazed land and compared loads with other land uses, including row crop agriculture and forestry. Concentrations in discharge have been regressed against standard grazing animal units per land area. Watersheds with concentrated livestock populations have been shown to discharge as much as 5 to 10 times more nutrients than watersheds in cropland or forestry. The other major water quality concern with grazing animals is pathogens, which may move from the wastes into surface water bodies or ground water. Major surface water quality problems associated with pathogens have been associated with grazing animals, particularly when they are not fenced out from streams and farm ponds. This paper presents an overview of water quality issues relating to grazing animals. PMID:15471806

Hubbard, R K; Newton, G L; Hill, G M

2004-01-01

404

Dairy Market Statistics Annual Summary  

NSDL National Science Digital Library

The USDA has made available the latest annual Dairy Market Statistics, a compendium drawn from the weekly Dairy Market News (discussed in the September 25, 1997 Scout Report for Business and Economics). Its 43 tables cover the areas of production, storage, purchases, butter, cheese, and dry and fluid milk and cream. One of the most useful aspects of the publication is the availability in one place of monthly and weekly averages for numerous data tables from the DMN.

405

43 CFR 4200.1 - Authority for grazing privileges.  

Code of Federal Regulations, 2014 CFR

...29, 1998] Group 4300—Grazing Administration; Alaska; Reindeer; General Note: The information collection requirements...whether an application to utilize the public lands in Alaska for reindeer grazing should be granted. The information will be used...

2014-10-01

406

43 CFR 4200.1 - Authority for grazing privileges.  

Code of Federal Regulations, 2012 CFR

...29, 1998] Group 4300—Grazing Administration; Alaska; Reindeer; General Note: The information collection requirements...whether an application to utilize the public lands in Alaska for reindeer grazing should be granted. The information will be used...

2012-10-01

407

43 CFR 4200.1 - Authority for grazing privileges.  

Code of Federal Regulations, 2011 CFR

...29, 1998] Group 4300—Grazing Administration; Alaska; Reindeer; General Note: The information collection requirements...whether an application to utilize the public lands in Alaska for reindeer grazing should be granted. The information will be used...

2011-10-01

408

43 CFR 4200.1 - Authority for grazing privileges.  

Code of Federal Regulations, 2013 CFR

...29, 1998] Group 4300—Grazing Administration; Alaska; Reindeer; General Note: The information collection requirements...whether an application to utilize the public lands in Alaska for reindeer grazing should be granted. The information will be used...

2013-10-01

409

Effects of Nitrogen Fertilization, Burning, and Grazing on Reserve Constituents  

E-print Network

Effects of Nitrogen Fertilization, Burning, and Grazing on Reserve Constituents of Big Bluestem of nitrogen fertilization, burning, and grazing on total nonstructural carbohydrate (TNC) and nitrogen and nitrogen reserves were lowered when growth exceeded photosynthetic production and nutrient assimilation

Owensby, Clenton E.

410

Effects of BST on oviductal and uterine genes encoding components of the IGF system in lactating dairy cows.  

PubMed

Lactating Holstein cows, averaging 80 d in milk, were used to examine effects of exogenous bovine somatotropin (bST) on oviductal and uterine genes encoding components of the insulin-like growth factor (IGF) system. About 12 h before expected ovulation in an Ovsynch protocol, cows were assigned randomly to receive bST (500 mg; n = 11) or serve as untreated controls (n = 10). Cows that ovulated (n = 9 bST, 8 control) were divided within treatment to be sacrificed on d 3 or 7 postovulation. Samples of oviductal and intercaruncular endometrial tissue from oviducts and uterine horns ipsilateral to the corpus luteum (CL) were collected and immediately frozen at -80 degrees C for subsequent mRNA analyses. Northern blots revealed mRNAs for IGF-II, IGF-binding protein-2 (IGFBP-2), and IGFBP-3 in all oviductal and endometrial tissues. Significant amounts of IGF-I and growth hormone receptor-1A (GHR-1A) mRNAs were detected in uteri but not in oviducts. The bST treatment had no effect on amount of IGF-I mRNA transcript in uterine endometrium. The mRNA encoding IGF-II was induced by bST in oviducts collected on both d 3 and 7 but was down-regulated in endometrium on d 7. Transcript of IGFBP-2 mRNA was greater in endometrial than oviductal tissues and did not differ between treatments. Both oviductal and endometrial IGFBP-3 mRNA concentrations increased between d 3 and 7 postovulation, with a tendency for greater endometrial IGFBP-3 mRNA in bST-treated cows on d 7. On d 7, concentrations of endometrial GHR-1A mRNA were 30% lower in bST-treated cows. Results indicate complex and tissue-specific regulation of the uterine IGF system components by exogenous bST. Some of those biological responses to bST may be important in early development of bovine embryos. PMID:12512599

Pershing, R A; Lucy, M C; Thatcher, W W; Badinga, L

2002-12-01

411

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

412

Variability in Protist Grazing and Growth on Different Marine Synechococcus Isolates?  

PubMed Central

Grazing mortality of the marine phytoplankton Synechococcus is dominated by planktonic protists, yet rates of consumption and factors regulating grazer-Synechococcus interactions are poorly understood. One aspect of predator-prey interactions for which little is known are the mechanisms by which Synechococcus avoids or resists predation and, in turn, how this relates to the ability of Synechococcus to support growth of protist grazer populations. Grazing experiments conducted with the raptorial dinoflagellate Oxyrrhis marina and phylogenetically diverse Synechococcus isolates (strains WH8102, CC9605, CC9311, and CC9902) revealed marked differences in grazing rates—specifically that WH8102 was grazed at significantly lower rates than all other isolates. Additional experiments using the heterotrophic nanoflagellate Goniomonas pacifica and the filter-feeding tintinnid ciliate Eutintinnis sp. revealed that this pattern in grazing susceptibility among the isolates transcended feeding guilds and grazer taxon. Synechococcus cell size, elemental ratios, and motility were not able to explain differences in grazing rates, indicating that other features play a primary role in grazing resistance. Growth of heterotrophic protists was poorly coupled to prey ingestion and was influenced by the strain of Synechococcus being consumed. Although Synechococcus was generally a poor-quality food source, it tended to support higher growth and survival of G. pacifica and O. marina relative to Eutintinnis sp., indicating that suitability of Synechococcus varies among grazer taxa and may be a more suitable food source for the smaller protist grazers. This work has developed tractable model systems for further studies of grazer-Synechococcus interactions in marine microbial food webs. PMID:21398485

Apple, Jude K.; Strom, Suzanne L.; Palenik, Brian; Brahamsha, Bianca

2011-01-01

413

Variability in protist grazing and growth on different marine Synechococcus isolates.  

PubMed

Grazing mortality of the marine phytoplankton Synechococcus is dominated by planktonic protists, yet rates of consumption and factors regulating grazer-Synechococcus interactions are poorly understood. One aspect of predator-prey interactions for which little is known are the mechanisms by which Synechococcus avoids or resists predation and, in turn, how this relates to the ability of Synechococcus to support growth of protist grazer populations. Grazing experiments conducted with the raptorial dinoflagellate Oxyrrhis marina and phylogenetically diverse Synechococcus isolates (strains WH8102, CC9605, CC9311, and CC9902) revealed marked differences in grazing rates-specifically that WH8102 was grazed at significantly lower rates than all other isolates. Additional experiments using the heterotrophic nanoflagellate Goniomonas pacifica and the filter-feeding tintinnid ciliate Eutintinnis sp. revealed that this pattern in grazing susceptibility among the isolates transcended feeding guilds and grazer taxon. Synechococcus cell size, elemental ratios, and motility were not able to explain differences in grazing rates, indicating that other features play a primary role in grazing resistance. Growth of heterotrophic protists was poorly coupled to prey ingestion and was influenced by the strain of Synechococcus being consumed. Although Synechococcus was generally a poor-quality food source, it tended to support higher growth and survival of G. pacifica and O. marina relative to Eutintinnis sp., indicating that suitability of Synechococcus varies among grazer taxa and may be a more suitable food source for the smaller protist grazers. This work has developed tractable model systems for further studies of grazer-Synechococcus interactions in marine microbial food webs. PMID:21398485

Apple, Jude K; Strom, Suzanne L; Palenik, Brian; Brahamsha, Bianca

2011-05-01

414

LEVELS OF PHOSPHORUS IN SOILS AND TROPHIC STATE OF LAKES ASSOCIATED WITH GRAZED AND HAYED FORAGE-BASED PASTURE SYSTEMS IN FLORIDA  

Technology Transfer Automated Retrieval System (TEKTRAN)

Forage-based livestock systems have been implicated as major contributors to deteriorating water quality, particularly for phosphorus (P) in fertilizers and manures affecting surface and ground water quality. Little information exists regarding possible magnitudes of nutrient losses from pastures th...

415

Use of Monensin Controlled-Release Capsules to Reduce Methane Emissions and Improve Milk Production of Dairy Cows Offered Pasture Supplemented with Grain  

Microsoft Academic Search

We examined the effects of monensin, provided by controlled-release capsules, on the enteric methane emissions and milk production of dairy cows receiving ryegrass pasture and grain. In a grazing experiment, 60 Holstein-Friesian cows were assigned randomly to 1 of2groups(controlormonensin).Cowsinthemonensin group received 2 controlled-release capsules, with the second capsule administered 130 d after the first. Milk production was measured for 100

C. Grainger; M. J. Auldist; T. Clarke; K. A. Beauchemin; S. M. McGinn; M. C. Hannah; R. J. Eckard; L. B. Lowe

2008-01-01

416

Effects of previous grazing nutrition and management on feedlot performance of cattle.  

PubMed

Management strategies designed to improve grazing animal performance can influence feedlot performance and carcass traits both positively and negatively. In spite of the economic relevance of potential interactions between grazing and finishing performance, controlled experiments evaluating integrated production systems are limited in number. Effects of grazing treatments can result from, or be overshadowed by, changes in gut fill, thus making it difficult to assign precise costs to different phases of production. Published reports have considered the effects of stocking rate, duration of grazing, forage characteristics, supplementation, and growth-promoting implants on subsequent finishing performance. Improvements in cattle performance attributed to changes in stocking rate generally have been neutral to positive with respect to effects on finishing performance. Comparisons among forages have led to the suggestion that forage species may contribute to differences in gastrointestinal fill of grazing cattle, thereby influencing gain and efficiency during the subsequent finishing phase. Creep-feeding suckling calves generally has increased preweaning performance but has had relatively little influence on performance during the subsequent finishing phase. Grain supplementation of stocker cattle during the grazing period has improved grazing performance, but effects on subsequent feedlot performance have been inconsistent. Potential carryover effects from protein and mineral supplementation also have been inconclusive. Lack of congruence among studies is puzzling but may be the consequence of highly varied production systems, differences in experimental procedures, and changes in gut fill or mass of internal organs. Based on the studies reviewed, the expression or absence of compensatory growth during the finishing phase appears to be related to the nutritional quality of forages utilized in the grazing period, with higher quality forages tending to yield greater compensatory effects. The bulk of evidence with suckling cattle and stocker implants suggests that effects on subsequent finishing performance are minimal. Attention is drawn to the noticeable lack of research pertaining to integrated production systems. A more thorough understanding of the interactions among grazing nutrition and management, finishing performance, and carcass traits is needed to facilitate greater economic exploitation of these relationships. PMID:15526788

Drouillard, J S; Kuhl, G L

1999-01-01

417

Within-day feeding behavior of lactating dairy cows measured using a real-time control system.  

PubMed

The suitability of a statistical model for describing within-day feeding behavior, and potential relationships between model parameters and commonly measured experimental variables were examined. Forty multiparous, midlactation Holstein cows were fed using a real-time control system to record the date of each visit to a feeder, entrance time, exit time, and feed consumed over a 6-wk period. Daily feed consumption, number of visits, meal duration, and within-visit rate of food intake were then calculated. Two peaks in within-day rates of feed intake were indicated, suggesting that feeding activity was randomly distributed around each peak, that is, binormal. Parameters describing the distributions (means, standard deviations, and the percentage of total feeding activity associated with each peak) were estimated. An adjusted average of 91% of the variation in within-day feeding activity was explained by the binormal model. Relationships between model parameters and commonly measured experimental variables were also identified; behavioral traits were correlated with total feed intake. Feeding activity patterns in literature data were also amenable to reanalysis by the binormal model. Lactating cows consistently exhibited a distinct diurnal pattern in feeding activity; they were most active near sunrise and again near sunset (crepuscular). Effects of various management operations (e.g., feeding and milking times and frequencies, and lighting) on within-day feeding patterns remain to be established, although a statistical model for evaluating them is now available. The patterns may have important implications for scheduling management activities to maximize feed intake and production. PMID:15829678

Shabi, Z; Murphy, M R; Moallem, U

2005-05-01

418

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

419

Microzooplankton grazing on Prorocentrum minimumand Karlodinium micrumin Chesapeake Bay  

Microsoft Academic Search

Potential grazing rates on the bloom forming dinoflagellates Prorocentrum minimumand Karlodinium micrum were measured in Chesapeake Bay during summer (2000). Cultured P. minimum and K. micrum cells were flu- orescently labeled with 5-chloromethylfluoroscein diacetate and introduced to ,200 mm filtered water. Microzoo- plankton grazing was assessed by measuring the disappearance of labeled prey over time. Grazing on P. minimum and

Matthew D. Johnson; Michelle Rome; Diane K. Stoecker

2003-01-01

420

7 CFR 760.305 - Eligible grazing losses.  

Code of Federal Regulations, 2012 CFR

...grazing losses. (a) A grazing loss due to drought is eligible for LFP only if the grazing...pastureland for the county, rated by the U.S. Drought Monitor as having a: (i) D2 (severe drought) intensity in any area of the...

2012-01-01

421

7 CFR 760.305 - Eligible grazing losses.  

Code of Federal Regulations, 2014 CFR

...grazing losses. (a) A grazing loss due to drought is eligible for LFP only if the grazing...pastureland for the county, rated by the U.S. Drought Monitor as having a: (i) D2 (severe drought) intensity in any area of the...

2014-01-01

422

7 CFR 760.305 - Eligible grazing losses.  

Code of Federal Regulations, 2013 CFR

...grazing losses. (a) A grazing loss due to drought is eligible for LFP only if the grazing...pastureland for the county, rated by the U.S. Drought Monitor as having a: (i) D2 (severe drought) intensity in any area of the...

2013-01-01

423

Intensive grazing by Barnacle geese depletes High Arctic seed bank  

Microsoft Academic Search

Studies in the Canadian Arctic show dramatic effects of increased goose grazing on vegetation structure and soil conditions, but little is known of the role of goose grazing in the European Arctic. We focused on how geese might affect plant recruitment via effects on seed production and soil seed bank in High Arctic Svalbard. Experimental grazing by captive Barnacle geese

D. P. J. Kuijper; J. P. Bakker; E. J. Cooper; R. Ubels; I. S. Jonsdottir; M. J. J. E. Loonen

2006-01-01

424

Grazing dynamics in intertidal rockpools: Connectivity of microhabitats  

Microsoft Academic Search

Differences between rockpool and emergent rock communities are often attributed to their contrasting physical conditions. However, differences in grazing pressure between rockpools and open rock could also exert an important structuring role. Greater densities and\\/or the lack of tidal constraints on foraging may allow grazing intensity to be greater in rockpools. Here, wax discs were deployed to compare grazing intensity

Laure M.-L. J. Noël; Steve J. Hawkins; Stuart R. Jenkins; Richard C. Thompson

2009-01-01

425

Tate et al. Riparian Grazing 1 Final Report  

E-print Network

Tate et al. Riparian Grazing 1 Final Report submitted January 2006 to USDA Western Sustainable Confirmation of Riparian Friendly Grazing Project Results and Development of Achievable, Site Specific Reference Conditions for Grazed Riparian Areas Principle Investigator Kenneth W. Tate, Rangeland Watershed

Tate, Kenneth

426

Grazing ability of European black pine understorey vegetation by goats  

Microsoft Academic Search

Goats’ utilizing ability of spontaneous vegetation, depending on stocking density, grazing season and day period, was studied on a European black pine (Pinus nigra Arnold subsp. nigra) reforested slope of the Pyrenees with direct observation of the animals’ grazing behaviour. Goats spent about 59% of their time eating in spring versus 85% in autumn. However, the mean grazing time (8.6h)

L. Torrano; J. Valderrábano

2005-01-01

427

Comparison of an early and normal weaning management system on cow and calf performance while grazing endophyte-infected tall fescue pastures.  

PubMed

A 3-yr study used 16 cows and their spring-born calves (yr 1) and 48 first-calf heifers (yr 2, n = 24; yr 3, n = 24) and their spring-born calves in a completely randomized design. All cows and heifers were Angus x Beefmaster, and calves were sired by Angus bulls. Cow-calf pairs were assigned randomly to one of two management systems: 1) an early-weaning system, in which steer and heifer calves were weaned at 108 d of age and fed a postweaning growing diet (EW), or 2) a normal weaning system, in which calves were weaned at 205 d without supplementation (NW). Before early weaning and within each management system, calves and their dams were maintained in two 1.4-ha, endophyte-infected tall fescue pastures for 35 d (yr 1) or 14 d (yr 2 and 3). Early-weaned calves and cow-calf pairs were then randomly allotted to 1.4-ha, endophyte-infected tall fescue pastures with two (yr 1) or three (yr 2 and 3) calves or cow-calf pairs per pasture (four pastures per management system). Cow weights and BCS changes and calf gains were measured from early to normal weaning. Dietary intakes and nutrient digestibilities by EW and NW calves were determined during two periods of yr 1 and three periods of yr 2 and 3. Total gains and BCS changes were greater (P < 0.01) for cows that produced EW calves in all years. Calf ADG from early to normal weaning did not differ (P = 0.32). Similar to ADG, BW of calves at normal weaning were not different (P = 0.11). Forage intake was greater (P < 0.01) by NW calves during Periods 2 and 3 of yr 1 and Periods 1 and 2 of yr 2 and 3; however, total DM and CP intakes were greater (P < 0.01) for EW calves in Periods 2 and 3 of each year. Intakes of NDF tended (P = 0.11) to be greater by EW calves across all years. Estimates of CP and NDF digestibilities were higher (P < 0.01) for EW calves during yr 1 and 2; however, all components of the diet consumed by NW calves in yr 3 were more digestible (P < 0.05) than those consumed by EW calves. These results show the condition of cows with EW calves was improved by early weaning and gains by calves weaned at 108 d to pasture plus a commercial grower diet were comparable to those by calves continuing to nurse dams until weaned at 205 d. PMID:15644522

Schultz, C L; Ely, D G; Aaron, D K; Burden, B T; Wyles, J

2005-02-01

428

Bulk Handling of Milk on Texas Dairy Farms.  

E-print Network

areas dur- tem of handling milk. ing the spring and summer of 1957 on dairy - farms which have converted their operations to Dairymen interviewed in North Texas had tanks ranging from 150 gallons to 1,000 gallons, , the bulk system of producing... and handling milk. while tanks in the Corous Christi area raneDd Texas dairy farmers are operating larger from 200 gallons to 1,000 gallons. The average units, milking more cows, selling more milk and tank in North Texas had a capacity of 400 gal. generally...

Parker, Cecil A.; Stelly, Randall, Moore, Donald S.

1958-01-01

429

Effects of nitrogen deposition and cattle grazing on productivity, invasion impact, and soil microbial processes in a serpentine grassland  

NASA Astrophysics Data System (ADS)

In recent decades, human activities have vastly increased the amount of biologically available nitrogen (N) in the biosphere. The resulting increase in N availability has broadly affected ecosystems through increased productivity, changes in species composition, altered nutrient cycles, and increases in invasion by exotic plant species, especially in systems that were historically low in N. California serpentine grasslands are N-limited ecosystems historically dominated by native species including several threatened and endangered plants and animals. Cattle grazing has emerged as the primary tool for controlling the impact of nitrophilic exotic grasses whose increased abundance has paralleled the regional traffic-derived increase in atmospheric N deposition. We examined the interactive effects of cattle grazing and N deposition on plant community composition, productivity, invasion resistance, and microbial processes in the Bay Area's largest serpentine grassland to determine the efficacy of current management strategies as well as the biogeochemical consequences of exotic species invasion. In the first two years of the study, aboveground net primary productivity decreased in response to grazing and increased in response to nitrogen addition. However, contrary to our hypotheses the change in productivity was not due to an increase in exotic species cover as there was little overall effect of grazing or N addition on species composition. Microbial activity was more responsive to grazing and N. Potential net N mineralization rates increased with N addition, but were not affected by grazing. In contrast, soil respiration rates were inhibited by grazing, but were not affected by N addition; suggesting strong carbon-limitation of soil microbial activity, particularly under grazing. Site differences in soil depth and grazing intensity were often more important than treatment effects. We suspect that the unusually dry conditions in the first two growing seasons inhibited the growth of exotic species and minimized the effects of cattle exclusion and N addition on species composition.

Pasari, J.; Hernandez, D.; Selmants, P. C.; Keck, D.

2010-12-01

430

Feasibility of Institutional Financing for Dairy Development  

Microsoft Academic Search

A commercial bank had undertaken an Integrated Development Project for dairy development in collaboration with a dairy plant. The scheme envisaged the supply of bank finances to the farmers for the purchase of quality cattle and repayments through milk supply to the dairy. A sample of beneficiaries were contacted to find out the impact of bank finances on their income.

George P S; Srivastava Uma Kant

431

Predicting Methane Production in Dairy Mohammad Ramin  

E-print Network

Predicting Methane Production in Dairy Cows Mohammad Ramin Faculty of Natural Resources (Karoline) #12;Predicting Methane Production in Dairy cows Abstract Methane is a potent greenhouse gas of methane (CH4) production from dairy cows would be of interest to develop mitigation strategies

432

Science Serving Vermonters Dairy Center of Excellence  

E-print Network

Science Serving Vermonters Dairy Center of Excellence #12;The University of Vermont DAIRY CENTER of EXCELLENCE Science Serving Vermonters A New Way to Benefit Dairy Producers · Forging Partnerships: UVM, Farmers, Industry & Government · Engaging Vermont Farmers as Research Partners · Helping Vermont

Bermingham, Laura Hill

433

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

434

Fungi: A major source of radiocesium contamination of grazing ruminants in Norway  

SciTech Connect

Transfer of radiocesium from vegetation to milk was studied in dairy goats grazing heavily contaminated mountain pasture in southern Norway in the years following the Chernobyl accident. Radiocesium activity in milk and green vegetation remained stable throughout 1986 and 1987. In 1988, a sudden three- to fivefold increase in milk radioactivity occurred during the second half of the summer. Whole-body content of radioactivity in sheep and reindeer also increased rapidly. This coincided with an abundant growth of fungal fruit bodies with radiocesium levels up to 100 times higher than green vegetation. Fungal radiocesium was found to be highly available in a digestibility study with goats. Milk radioactivity levels in the field could be accounted for by consumption of as little as 20-100 g d-1 of fungal dry matter (DM). The importance of fungal fruit bodies in transferring radiocesium to ruminants was further substantiated by comparing meat activities in grazing ruminants in 1988 and 1989. Fungal fruit bodies were present in minor quantities in 1989, and radioactivity levels in sheep and reindeer in August-September were only 28-35% of those in 1988. This ability of fungi to mobilize radiocesium from natural soils and transfer the isotopes into the human food chain greatly enhances the vulnerability of food production in natural ecosystems to radiocesium pollution.

Hove, K.; Pedersen, O.; Garmo, T.H.; Hansen, H.S.; Staaland, H.

1990-08-01

435

The economics of dairy production.  

PubMed

The structure of the dairy farm industry has been changing rapidly in recent years. Milk production has increased, with dramatic increases in milk produced per cow and with a steep decline in number of milk cows and fewer farms with larger herds. The change in dairy farm size has not been uniform across regions. The growth in farm size has occurred much more rapidly in the Pacific and South regions than in the traditional dairy-producing regions (Upper Midwest, Northeast, and Corn Belt). Using USDA data to examine costs and returns over time reveals that the incentives to produce milk have been much greater in the Pacific and South regions in recent years. Although the cash costs are similar across regions, accounting for all costs including unpaid factors such as labor and capital replacement yields a clear advantage for the Pacific region. Dairy farm size and cost of production are jointly determined. The incentive to increase farm size is derived from the economies of size that may be achieved by spreading the capital, labor, and managerial costs across more units of milk production. Empiric evidence from previous studies indicates a declining cost of production over a large range of herd sizes. Even in the presence of a flat average cost curve, the incentive to maximize farm income provides incentive to increase production. Adjustment costs may fix dairy production facilities in their current use. Those firms facing higher adjustment costs because of individual or regional characteristics or because of different timing of growth will be smaller or grow more slowly than if they faced smaller adjustment costs. This situation may explain the continued lag of farm size and technology adoption in the traditional dairy producing regions relative to the Pacific and South regions where the more recent population growth coincided with the presence of modern, large-scale production technologies. Finally, dairy marketing policies almost certainly have affected the structure and regional pattern of dairy farm size and production. For the most part, however, the policy effects have been of indirect nature. The Pacific region has grown (despite having the lowest average price) by taking advantage of economies of size by specializing in milking cows. The United States dairy industry is a technologically advanced, well-managed, and economically important sector of United States agriculture. Future challenges include the ability to remain viable economically while dealing with environmental and social sustainability issues in the form of new constraints from formal policies and from consumer perceptions. PMID:12951734

Wolf, Christopher A

2003-07-01

436

Computerized dairy records management systems  

E-print Network

the same from previous to current test day. Fat% and protein% values across 30 lactations were almost identical, 2ndL cows producing the lowest values. TABLE A. 4. MASTITIS-PRODUCTION RELATIONSHIP HOLSTEIN HERD Cows CI'DM PTDM SCCSTM SCCSLM CTD%F CID%P...

Acosta, Alejandro E. Gonzalez

1992-01-01

437

Stocking Rate: The Key Grazing Management Decision  

E-print Network

stocking rate removes almost all edible forage so that only immature plants remain. While this immature forage is high quality, there isn?t enough of it. In grazing, both forage quality and forage quantity are important, and both affect livestock...

Lyons, Robert K.; Machen, Richard V.

2001-07-19

438

Aurora Organic Dairy Phase III: Corporate Sustainability Report  

E-print Network

Aurora Organic Dairy Phase III: Corporate Sustainability Report Rosemary Lapka, Neesha Modi, Lauren: Corporate Sustainability Report By: Rosemary Lapka Neesha Modi Lauren Start David Weinglass A project REPORT Rosemary Lapka, Neesha Modi, Lauren Start and David Weinglass Center for Sustainable Systems

Edwards, Paul N.

439

Dairy Cow Culling Strategies: Making Economical Culling Decisions  

Microsoft Academic Search

The purpose of this report was to examine impor- tant economic elements of culling decisions, to review progress in development of culling decision support systems, and to discern some of the potentially re- warding areas for future research on culling models. Culling decisions have an important influence on the economic performance of the dairy but are often made in a

Terry W. Lehenbauer; James W. Oltjen

1998-01-01

440

Generalized Linear Mixed Models in Dairy Cattle Breeding1  

Microsoft Academic Search

Fitness and fertility traits of dairy cattle are of increasing importance and are often measured on a discrete scale. The development and application of generalized linear mixed models to the genetic analy- sis of these traits are reviewed. Because current genetic evaluation systems are predominantly based on animal models, the inferential challenges of highly parameterized generalized linear mixed models are

Robert J. Tempelman