Factors affecting milk yield at peak and during current lactation of Holstein cows
نویسندگان
چکیده
منابع مشابه
Genetic correlation of average somatic cell score at different stages of lactation with milk yield and composition in Holstein cows
Genetic and non-genetic correlations of the average somatic cell score (SCS) at different stages oflactation (100, 150, 200, 305 and 365 days in milk) with lactation performance were estimated based on thefirst lactation records of Iranian Holstein calving during 2000 to 2009. (Co) variance components wereestimated using derivative-free REML based on multiple traits animal models. The estimated...
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Milk yield records (305d, 2X, actual milk yield) of 123,639 registered first lactation Holstein cows were used to compare linear regression (y = β(0) + β(1)X + e), quadratic regression, (y = β(0) + β(1)X + β(2)X(2) + e) cubic regression (y = β(0) + β(1)X + β(2)X(2) + β(3)X(3) +e) and fixed factor models, with cubic-spline interpolation models, for estimating the effects of inbreeding on milk yi...
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ژورنال
عنوان ژورنال: Journal of Animal and Feed Sciences
سال: 2004
ISSN: 1230-1388
DOI: 10.22358/jafs/73969/2004