title: Genetic association between susceptibility to clinical mastitis and protein yield in norwegian dairy cattle.
abstract: The objective of this study was to examine associations between susceptibility to clinical mastitis and protein yield in first-lactation Norwegian Dairy Cattle (NRF) cows. Records from 372,227 first-lactation daughters of 2411 NRF sires were analyzed bivariately, using a threshold-liability model for clinical mastitis and a linear Gaussian model for 305-d protein yield. The mean (SD) of the posterior distribution of heritability was 0.08 (0.004) for susceptibility to clinical mastitis and 0.19 (0.007) for 305-d protein yield. The posterior mean (SD) of the genetic correlation between susceptibility to clinical mastitis and 305-d protein yield was 0.43 (0.03). Posterior means of the correlations between herd-5-yr effects, and between model residuals were 0.19 and -0.008, respectively. Corresponding estimates of genetic, herd-5-yr, and residual correlations from a bivariate linear model analysis were 0.42, 0.18, and -0.008, respectively. An antagonistic genetic relationship between clinical mastitis and protein yield was corroborated.
authors.affiliation: Department of Animal and Aquacultural Sciences, Agricultural University of Norway, P.O. Box 5003, N-1432 As, Norway. bjorg.heringstad@umb.no
authors.forename: B
authors.initials: B
authors.lastname: Heringstad
authors.forename: Y M
authors.initials: YM
authors.lastname: Chang
authors.forename: D
authors.initials: D
authors.lastname: Gianola
authors.forename: G
authors.initials: G
authors.lastname: Klemetsdal
mesh_terms: D000818:Animals; D001499:Bayes Theorem; D001947:Breeding; D002417:Cattle / Q000235:genetics*; D005260:Female; D020022:Genetic Predisposition to Disease; D007774:Lactation / Q000235:genetics / Q000502:physiology; D016014:Linear Models; D008297:Male; D008414:Mastitis, Bovine / Q000235:genetics*; D008892:Milk / Q000737:chemistry; D008894:Milk Proteins / Q000032:analysis* / Q000235:genetics; D016011:Normal Distribution; D009664:Norway
chemical_list: D008894:Milk Proteins