Hostname: page-component-586b7cd67f-2plfb Total loading time: 0 Render date: 2024-11-23T13:41:48.674Z Has data issue: false hasContentIssue false

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
Get access

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

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Duysings, P.M.J. Hooghiemstra, L.J. and Politiek, R.D., 1979. Milk cell count in first lactations of progeny groups of Al bulls. Z.Tierzucht Zuchl. Diol. 96: 4855.Google Scholar
Emanuelson, U. 1987. Genetic Studies on the Epidemiology of Mastitis in Dairy Cattle. Report No 73. Swedish University of Agricultural Sciences.Google Scholar
Harvey, W.R., 1977. Users guide for LSML76.Google Scholar
Hill, W.G., Edwards, M.R. and Ahmed, M. -K.A., 1983. Heritability of milkyield and composition at different levels and variability of production Anim. Prod. 36: 5968.Google Scholar
Kennedy, B.W., Sethar, M.S., Moxley, J.E. and Downey, B.R., 1982. Heritability of somatic cell count and its relationship with milkyield and composition in Holstcins. J.Dairy Sci. 65: 843847.Google Scholar
Meyer, K., 1986. REML to estimate genetic parameters in practice. Third World Congress on Genetics applied to Livestock Production.Google Scholar
Monardes, H.G., Kennedy, B.W. and Moxley, J.E., 1982. Heritabilities of measures of somatic cell count per lactation. J. Dairy Sci. 66: 17071713.Google Scholar
Patferson, H.D., Thompson, R., 1971. Recovery of interblock information when block sizes are unequal. Biometrika 58 :545554.Google Scholar
Shook, G.E., Ruvuna, F and Ali, A.K.A., 1982. Genetic Parameters for lactation average of somatic cell concentration in milk. Proc. 2nd World Congr. Genet. Appl. Livcst. Prodn 8: 142147.Google Scholar
Swanson, G.J.T. and MrsBellamy, H.J., 1991. Estimation of Genetic Parameters for Conformation Traits assessed on a linear scale in Friesian Holstein heifers. Proc. BSAP Winter Mtg. 1991.Google Scholar
Vecht, U., Shook, G.E., Politiek, R.D., Grootenhuis, G., Koops, W.J. and Groothuis, D.G., 1985. Effect of bull selection for somatic cell count in first lactation on cell counts and pathogens in later lactations. J. Dairy Sci. 68: 29953003.Google Scholar
Wood, P.D.P. and Booth, J.M., 1983. Variation in milk cell counts during lactation of British Friesian Cattle, Anim. Prod. 36: 335339.Google Scholar