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Genetic and environmental factors affecting some measures of yield and fertility in a registered Canadian Holstein dairy herd in Iran

Published online by Cambridge University Press:  20 November 2017

Ali Toosi
Ali Toosi*
Affiliation:
Dept. of Anim. Sci., College of Agriculture, Ferdowsi Univ., P.O. Box 91775-1163 Mashhad, Iran
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Extract

Milk production is the most important trait in dairy cattle breeding. Measures of additional traits are also important. Traits of lactation curve are important in their relation to production characteristics. The two major reasons for which dairy cows are disposed are fertility problems and low milk yield (Hansen et al.,1983). The objectives of this study were 1) To evaluate effects of some environmental factors on some measures of yield and fertility, and 2) To estimate genetic parameters for these traits applying REML procedures under sire model.

Type
Poster Presentations
Information
Proceedings of the British Society of Animal Science , Volume 2002 , 2002 , pp. 190
Copyright
Copyright © The British Society of Animal Science 2002

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References

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