A Measure of Persistency of Lactation in 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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Milk production is largely dependent on the shape of the lactation curve. Relevant elements of the lactation pattern are the peak yield, which represents the maximum milk yield during the lactation, and the lactation persistency, which expresses the ability of animals to maintain a reasonably constant milk yield after the lactation peak (Figure 1). Thus, persistent animals are those that show f...
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ژورنال
عنوان ژورنال: Journal of Dairy Science
سال: 1943
ISSN: 0022-0302
DOI: 10.3168/jds.s0022-0302(43)92739-0