Relationships Between Conformation and Calving Interval in Holstein Cows
نویسندگان
چکیده
منابع مشابه
Association between the lactation curve shape and calving interval in Holstein dairy cows of Iran
This study was carried out to investigate the relationship between early lactation curve parameters andcalving interval in Holstein cows of Iran. In order to describe the lactation curve, the incomplete gammafunction was fitted to 5,754,428 test-day milk records corresponding to 766,108 lactations on 315,634 cowsin 2,448 herds. Cows with higher milk yield during early lactation had shorter calv...
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Genetic and phenotypic (co)variances for mature equivalent yield of 4% FCM and calving interval were simultaneously estimated by REML for grade Holstein cows in first and second parity. Data were 305d mature equivalent lactation records and calving dates for 299,441 daughters of 2489 AI sires first calving from 1970 to 1985 in California, New York, or Texas. Data were divided into three time pe...
متن کاملGenetic relationships between calving interval and linear type traits in South African Holstein and Jersey cattle
Genetic correlations between first calving interval (CI) and linear type traits in South African Holstein and Jersey cattle were estimated to assess the possibility of using type information as selection criteria for CI. All linear type traits routinely evaluated under the National Genetic Evaluation Programme (18 for Jersey and 17 for Holstein) were considered. Data were obtained from the Nati...
متن کاملassociation between the lactation curve shape and calving interval in holstein dairy cows of iran
this study was carried out to investigate the relationship between early lactation curve parameters andcalving interval in holstein cows of iran. in order to describe the lactation curve, the incomplete gammafunction was fitted to 5,754,428 test-day milk records corresponding to 766,108 lactations on 315,634 cowsin 2,448 herds. cows with higher milk yield during early lactation had shorter calv...
متن کاملSimple and Constrained Selection Indices with and without Calving Interval Included in Selection Goal Function for Holstein Cows of Iran
Two selection goals of inclusion or exclusion of calving interval (CI) in the selection goal function for Holstein cows in Iran, besides milk yield, milk fat percentage, and milk protein percentage, were studied. Four selection indices were composed of using the information on production traits, CI and / or days from calving to first insemination (DFI). The results of the predicted genetic grow...
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ژورنال
عنوان ژورنال: Journal of Dairy Science
سال: 1986
ISSN: 0022-0302
DOI: 10.3168/jds.s0022-0302(86)80775-5