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Full-Text Articles in Life Sciences
Genetic Parameters And Responses Of Linear Type, Yield Traits, And Somatic Cell Scores To Divergent Selection For Predicted Transmitting Ability For Type In Holsteins, B. J. Degroot, Jeffrey F. Keown, L. Dale Van Vleck, Erin L. Marotz
Genetic Parameters And Responses Of Linear Type, Yield Traits, And Somatic Cell Scores To Divergent Selection For Predicted Transmitting Ability For Type In Holsteins, B. J. Degroot, Jeffrey F. Keown, L. Dale Van Vleck, Erin L. Marotz
Department of Animal Science: Faculty Publications
The objective was to examine the direct and correlated responses of linear type, yield traits, and somatic cell scores (SCS) to divergent selection for predicted transmitting ability for type (PTAT) in Holsteins, while maintaining selection for yield traits across lines. For four generations, one-half of the University of Nebraska research Holstein herd was bred to Holstein sires with PTAT -1.50 and the other half to sires with PTAT - 1.25, with nearly equal predicted transmitting abilities for yield traits for both groups. Estimates of genetic and residual correlations and heritabilities were obtained from REML estimates of (co)variance components. Model for …
Research On Various Testing Procedures And Different Methods Of Estimating Lactation Milk Yield In Dairy Cattle, Atti̇la Kaya, Can Uzmay, Yavuz Akbaş, İbrahi̇m Kaya, Sencer Tümer
Research On Various Testing Procedures And Different Methods Of Estimating Lactation Milk Yield In Dairy Cattle, Atti̇la Kaya, Can Uzmay, Yavuz Akbaş, İbrahi̇m Kaya, Sencer Tümer
Turkish Journal of Veterinary & Animal Sciences
This research was carried out to determine the effect of various milk sampling intervals and different methods on the accuracy of estimation of lactation milk yield in dairy cattle. Individual daily milk weights of 599 Holstein, Simmental and Brown Swiss lactations from the Aegean Agricultural Research Institute were used. It was assumed that test-day milk yields were obtained by regular and irregular intervals of 28 d and 56 d, with the irregular intervals having a standard deviation of 5 d. From test-day milk yields, 305 d milk yields were estimated by the Holland (Lactation yield = mean of test day …