AIM Basic objective of this research was to compare two rabbit lines: V-line (exotic line), Alexandria (local synthetic line) for yield and composition of milk product and their effect on productive performance of rabbits. MATERIALS AND METHODS The experiment was conducted on 80 does and their kits. Milk yield (MY) of each doe and milk composition (MC) were recorded at 3rd week of lactation. ...

collected data in animal breeding center of iran from 1983 to 2003 was used to estimate the genetic parameters of milk yield in iranian holstein cattle. genetic parameters were estimated, using single and three trait animal models. records of three lactations were divided into thre esub groups according to average milk yield, climitical regions and herd sizes. all variance components in the thr...

Weight gain of young dairy replacement heifers, even over several months, is highly variable, lowly heritable, and a poor indicator of either weight at calving or first lactation milk yield. Voluntary forage consumption is much less variable, more heritable, and a better predictor of weight at calving and milk yield. Weight at calving is highly heritable but not correlated genetically with milk...

The objective of this study was to carry out a sensitivity analysis on the impact of various production strategies and performance levels on the relative economic values (REVs) of traits in dairy sheep. A bio-economic model implemented in the program package ECOWEIGHT was used to simulate the profit function for a semi-extensive production system with the Slovak multi-purpose breed Improved Val...

The objective of this study was to evaluate production response and more specifically percentage and yield of fat in milk from dairy cows fed distillers grains with added solubles (DGS). It was hypothesized that the oil present in DGS would decrease milk fat yield. Four dietary treatments consisted of dried DGS replacing soybean meal and soybean hulls. The DGS inclusion rates as a percentage of...

Six classical growth functions (monomolecular, Schumacher, Gompertz, logistic, Richards, and Morgan) were fitted to individual and average (by parity) cumulative milk production curves of Canadian Holstein dairy cows. The data analyzed consisted of approximately 91,000 daily milk yield records corresponding to 122 first, 99 second, and 92 third parity individual lactation curves. The functions ...

Risk of culling consequent to the main health disorders occurring in the current production systems are reviewed. Survival analysis models including health disorders as time-dependent variables are deemed to be the most appropriate to assess their effects because they allow a better description of the exact follow-up of disease history. Farmers preferentially consider health events in the curre...

JUOZAITIENE, V., A. JUOZAITIS: The influence of somatic cell count in milk on reproductive traits and production of Black-and-White cows. Vet. arhiv 75, 407414, 2005. ABSTRACT The aim of this study was to estimate the relationships between somatic cell count in milk, reproduction traits and milk production of cows of the Black-and-White breed. The research was carried out on 412 herds of the ac...

The gene encoding the brain-derived neurotrophic factor (BDNF) has been repeatedly associated with human obesity. As such, it could also contribute to the regulation of energy partitioning and the amount of secreted milk fat during lactation, which plays an important role in milk production in dairy cattle. Therefore, we performed an association study using estimated breeding values (EBVs) of b...

The objective of the current study was to investigate the effect of N-carbamoylglutamate (NCG) supplementation on milk production and nitrogen (N) utilization in Chinese Holstein dairy cows. Sixty multiparous cows (78±17.3 d in milk, 635±61.00kg of body weight, and 41.9±7.9kg/d milk yield; mean ± SD) were blocked by parity, days in milk, and milk yield and randomly allocated to 1 of 4 groups, e...