Original scientific paper
GENETIC TRENDS IN MILK YIELD AND SOME REPRODUCTIVE TRAITS OF HOLSTEIN FRISIAN CATTLE
Vitomir Vidović
; Agricultural University Novi Sad, Novi Sad, Srbia
Abstract
Investigations of genetic trends in milk yield and some reproductive traits (period of pregnancy and service period) of Holstein cattle were carried out in 12,335 lactations of 4,700 cows of 53 different siries in the period from 1978 to 1988. Estimations of genetic parameters made in these investigations were within the limits found in literature. Trends after the selection of cows for milk yield did not reflect significantly on the duration of pregnancy. Although the extension of the service period in selection for 4 % MKM was not high, the trend obtained confirms the supposition that the established changes can have significant effects.
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Keywords
Hrčak ID:
161933
URI
Publication date:
25.7.1990.
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