Genetic evaluation of lactation persistency for five breeds of dairy cattle
نویسندگان
چکیده
منابع مشابه
Genetic evaluation of lactation persistency for five breeds of dairy cattle.
Cows with high lactation persistency tend to produce less milk than expected at the beginning of lactation and more than expected at the end. Best prediction of lactation persistency is calculated as a function of trait-specific standard lactation curves and linear regressions of test-day deviations on days in milk. Because regression coefficients are deviations from a tipping point selected to...
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Cows with high persistency tend to produce less milk than expected at the beginning of lactation and more than expected at the end. Best prediction of persistency was calculated as a function of a trait-specific standard lactation curve and a linear regression of test-day deviations on days in milk. Regression coefficients were deviations from a balance point to make yield and persistency pheno...
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The calculation and publication of all dairy cattle genetic evaluations in Canada is the responsibility of Canadian Dairy Network (CDN). An 8-member board of directors, the majority being dairy producers, governs this non-profit national organization. Member organizations include all breed associations, milk recording agencies and artificial insemination centres across Canada as well as Dairy F...
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ژورنال
عنوان ژورنال: Journal of Dairy Science
سال: 2009
ISSN: 0022-0302
DOI: 10.3168/jds.2008-1825