The cost of milk production by farm size was decomposed into frontier and efficiency components with a stochastic cost curve using data on 755 USA dairy farms from the year 2000. The estimated frontier function is much flatter than the composite cost curve, and although the frontier cost of production decreases with farm size, that cost reduction is not as pronounced as a cost curve that includ...

One hundred and sixty seven Droughtmaster cows with calves were used in two experiments to evaluate the effect of early weaning and creep feeding on cow reproduction rates. Weaning of calves that weighed 48-92 kg instead of the conventional weaning weight of about 180 kg improved cow live weights and increased pregnancy rates by 48% at weaning. The early weaned calves were raised on Stylosanthe...

The feeding and rumination behaviour of dairy cows can be monitored by different techniques and can provide useful information for dairy herd management. Among feeding characteristics, individual feed intake of cows is of utmost interest, but as weighing troughs have high space and cost requirements their implementation is limited to the research area. The objective of the present study was to ...

successful pasture-based milk production systems pivot on balancing dairy cows’ feed requirements with seasonal and annual fluctuations in pasture production. in order to maximise cow production from grazing dairy systems, it is necessary to reach an efficient utilization of grazed grass for feeding cows and the development of appropriate grazing management systems designed to maximize daily pa...

in order to examine the effect of using rumen protected methionine (mepron, evonik industries, hanau, germany) on productive and reproductive performance under field condition, 195 holstein cows were used in a unbalanced completely randomized design and 2 groups. experimental treatments consisted of: 1) control group with 110 holstein dairy cows (71±51 dim and 47.5±12 milk yield) and without me...

Dietary intake is the predominant route for human exposure to perfluorooctane sulfonic acid (PFOS). Single pollution events may thus affect human exposure if polluted ground and water is used to produce animal feed or food. In this study, a physiologically based pharmacokinetic (PBPK-) model is derived that describes the uptake of PFOS from contaminated feed by cows and its subsequent eliminati...

the aim followed in the present study was to investigate the economic aspects of , and to derive economic weights (ews) for mature body weight (mbw) as well as for age at first calving (afc) in holstein dairy cattle of iran. economic values (evs) for traits were estimated using trait-by-trait bio-economic models. absolute evs were rls -16400 and -17900 per cow per year for mbw and afc, respecti...

Bovine Spongiform Encephalopathy (BSE, Mad cow disease) is generally considered to be caused by recycling animal by-products as ingredient in animal, especially ruminant, feed. Feed bans were enforced to minimize the risk on infections, and monitoring programs are effectuated for controlling the ban. The only official detection method is visual (microscopic) examination of the presence of prima...