Extension Factors for Trimester Yields of Milk and Fat
نویسندگان
چکیده
منابع مشابه
Method R estimates of heritability for milk, fat, and protein yields of United States dairy cattle.
Heritabilities for milk, fat, and protein yields were estimated from first lactation data used for USDA-Dairy Herd Improvement Association (DHIA) genetic evaluations. Contemporary group assignments and standard deviations within herd-year were determined with the procedure used for national evaluations. Pedigree data were included for animals born since 1970; yield data were included for cows b...
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ژورنال
عنوان ژورنال: Journal of Dairy Science
سال: 1985
ISSN: 0022-0302
DOI: 10.3168/jds.s0022-0302(85)80914-0