Longevity in relation to age at first calving and first laction yield in Karan-Swiss cows
1984
Bhatnagar, D.S. | Sharma, R.C. (National Dairy Research Inst., Karnal (India))
The overall mean of age at first calving, 1st lactation yield, days in lactation and longevity of 927 Karan Swiss cows commencing their first lactation during 1966-82 were 33.3+-0.2 months, 2680.2+-40.7 kg, 339.8+-3.4 days and 2.88+-0.1 lactation completed respectively. Heifers calfing earlier and those having higher 1st lactation yield tended to be in the herd for completing more number of lactation. Age at first calving appeared to be relatively more important than the 1st lactation production though both were positively correlated
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