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Estimation of genetic parameters for milk cell count and correlations with production traits in friesian holstein heifers

Published online by Cambridge University Press:  24 November 2017

G.J.T. Swanson
Affiliation:
Milk Marketing Board, Thames Ditton, Surrey, KT7 0EL
A. Gnanasakthy
Affiliation:
Milk Marketing Board, Thames Ditton, Surrey, KT7 0EL
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Extract

Mastitis is a major source of culling and economic loss in the dairy herd. To date in England and Wales the main monitor of mastitis both within a herd and nationally is provided by monthly herd milk cell counts. The main thrust of mastitis control programmes has been to improve management practices such as dry cow treatment and milk machine testing. Interest has also been shown in the use of milk cell count as an indirect means of selecting for resistance to mastitis infection. Wood and Booth (1983) indicated that the cell count at the third monthly recording had the highest correlation with lactation mean cell count. The objective of this study was to estimate the herilability of somatic cell count, taken at the third recording after calving in the heifer lactation and to examine the association between cell count and production traits.

Type
Dairy Cattle Breeding
Copyright
Copyright © The British Society of Animal Production 1991

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