Longevity and lifetime performacne of tharparkar cows
2001
Gahlot, G.C. (Rajasthan Agriculture University, Bikaner (India)) | Pant, K.P. (Central Research Institue on Goat, Makhdoom (India)) | Barahat, N.K. (Veterinary College, Bikaner (India). Deprtment of Animal Breeding and Genetics)
The lactation records of 772 Tharparkar cows of 2 farms, viz. Central Cattle Breeding Farm, Suratgarh and Livestock Research Station, Chandan, were analyzed for overall assessment of breed lifetime performance and adaptability. All lactation records (1968-96) up to disposal of cows were taken into consideration. The effect of farm period of calving, season of calving, productive life and age at first calving were studied through analysis of variance. Farm-wise there was significant variation in herd life, productive life, lifetime milk yield, lifetime parity, MY/LL, MY/PL, per cent days open, per cent days dry and breeding efficiency of Tharparkar cows. The period of first calving contributed significant variation in herd life, lifetime milk yield, lifetime parity, number of days in milk, MY/LL, MY/PL and per cent days dry. The periodic means indicate that managemental condition in later years improved a lot. Season of first calving was found significant only for lifetime milk yield, MY/LL and MY/PL. Cows calved in winter showed higher lifetime milk production than the cows calved in rest of 2 seasons. Monsoon season calvers were adversely affected by managemental practices. Farm x season interaction was nonsignificant for lifetime traits. The regression of lifetime and longevity traits on productive life was highly significant which indicated that these traits could be controlled by manipulating productive life of cows. The effect of age at first calving on herd life and productive life was highly significant whereas the variation in the lifetime milk yield due to differences in age at first calving was nonsignificant in Tharparkar cows.
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Эту запись предоставил Indian Council of Agricultural Research