Estimates of Genetic Trend in an Artificial Insemination Progeny Test Program and Their Association with Herd Characteristics
نویسندگان
چکیده
منابع مشابه
Estimates of genetic trend in an artificial insemination progeny test program and their association with herd characteristics.
Individual lactation records from Holstein cows in 3449 herds participating in an AI stud's young sire sampling program from 1971 to 1987 were used to characterize the sampling program and to estimate genetic merit and trend. Average genetic merit of cows in sampling program herds was consistently superior to the average genetic merit of cows in the US population. Genetic trend of sires of firs...
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15 صفحه اولUsability for genetic evaluations of records from herds participating in progeny test programs of artificial insemination organizations.
Thirteen AI organizations provided identification of herds that participated in their progeny test programs in 1989 and 1990; 15% of those herds participated in programs of more than one AI organization, but only 2.6% participated in programs of more than two AI organizations. Of the 19,589 participating herds, 82 and 76% were enrolled in DHI test plans that were considered to be usable for gen...
متن کاملOverview of progeny-test programs of artificial-insemination organizations in the United States.
Characteristics of progeny-test (PT) programs of artificial insemination (AI) organizations in the United States were examined for changes since 1960. Mean number of bulls that were progeny tested annually by major AI organizations during the mid 1990s was 11 for Ayrshires, 24 for Brown Swiss, 21 for Guernseys, 1261 for Holsteins, 112 for Jerseys, and 3 for Milking Shorthorns. Mean parent age a...
متن کاملTimeliness and effectiveness of progeny testing through artificial insemination.
Progeny-test (PT) programs of US artificial-insemination (AI) organizations were examined to determine timeliness of sampling, PT daughter distribution, rate of return of PT bulls to widespread service, and genetic merit of PT bulls compared with AI-proven and natural-service (NS) bulls. Bull age at semen release and at birth and calving of PT daughters was documented by breed (Ayrshire, Brown ...
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ژورنال
عنوان ژورنال: Journal of Dairy Science
سال: 1992
ISSN: 0022-0302
DOI: 10.3168/jds.s0022-0302(92)77986-7