<abstract xmlns="http://www.w3.org/1999/xhtml"><p>Cases of mastitis (CM) from 38,236 lactations belonging to 16,497 cows were recorded on seven farms in the Czech Republic from 1996 to 2014. Clinical mastitis was analyzed with linear animal model as an all-or-none trait for each recorded lactation (CM305) and separately for each trimester of lactation (CM1, CM2, and CM3). Bivariate linear animal models were used to estimate the genetic correlation between these CM traits and lactation means for somatic cell score (SCS305), the interval between calving and first insemination (INT) and days open (DO). Factors included in the linear model were parity, herd, year of calving, calving season, fixed linear and quadratic regression on age at first calving, fixed linear and quadratic regression on milk production in the corresponding parity, permanent environmental effect of the cow, and additive genetic effect of the cow. Estimated heritabilities of the CM traits ranged from 0.01 to 0.03. Permanent environmental effects accounted for approximately two-thirds of the phenotypic variance. Genetic correlations of SCS305 with CM traits were 0.85±0.029, 0.81±0.086, 0.82±0.087, and 0.67±0.088 for CM305, CM1, CM2, and CM3, respectively. Genetic correlations of INT with CM305, CM1, CM2, and CM3, respectively, were 0.22±0.065, 0.19±0.084, 0.20±0.121 and 0.15±0.121: and genetic correlations of DO and the four CM traits were 0.28±0.079, 0.26±0.101, 0.43±0.134, and 0.15±0.131. For the 140 sires in the dataset, Spearman rank correlations among breeding values for the four CM traits and for SCS305 were uniformly high at 0.99±0.001.</p></abstract>

Cases of mastitis (CM) from 38,236 lactations belonging to 16,497 cows were recorded on seven farms in the Czech Republic from 1996 to 2014. Clinical mastitis was analyzed with linear animal model as an all-or-none trait for each recorded lactation (CM305) and separately for each trimester of lactation (CM1, CM2, and CM3). Bivariate linear animal models were used to estimate the genetic correlation between these CM traits and lactation means for somatic cell score (SCS305), the interval between calving and first insemination (INT) and days open (DO). Factors included in the linear model were parity, herd, year of calving, calving season, fixed linear and quadratic regression on age at first calving, fixed linear and quadratic regression on milk production in the corresponding parity, permanent environmental effect of the cow, and additive genetic effect of the cow. Estimated heritabilities of the CM traits ranged from 0.01 to 0.03. Permanent environmental effects accounted for approximately two-thirds of the phenotypic variance. Genetic correlations of SCS305 with CM traits were 0.85±0.029, 0.81±0.086, 0.82±0.087, and 0.67±0.088 for CM305, CM1, CM2, and CM3, respectively. Genetic correlations of INT with CM305, CM1, CM2, and CM3, respectively, were 0.22±0.065, 0.19±0.084, 0.20±0.121 and 0.15±0.121: and genetic correlations of DO and the four CM traits were 0.28±0.079, 0.26±0.101, 0.43±0.134, and 0.15±0.131. For the 140 sires in the dataset, Spearman rank correlations among breeding values for the four CM traits and for SCS305 were uniformly high at 0.99±0.001.

Genetic Parameters for Clinical Mastitis, Fertility and Somatic Cell Score in Czech Holstein Cattle

Annals of Animal Science

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Cases of mastitis (CM) from 38,236 lactations belonging to 16,497 cows were recorded on seven farms in the Czech Republic from 1996 to 2014. Clinical mastitis...

Genetic Parameters for Clinical Mastitis, Fertility and Somatic Cell Score in Czech Holstein Cattle

Published Online: Oct 27, 2017

Page range: 1007 - 1018

Received: Aug 15, 2016

Accepted: May 12, 2017

DOI: https://doi.org/10.1515/aoas-2017-0006

Keywords
mastitis, somatic cell score, fertility, genetic parameters, Holstein cattle

© 2017 Ludmila Zavadilová et al., published by De Gruyter Open

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Genetic Parameters for Clinical Mastitis, Fertility and Somatic Cell Score in Czech Holstein Cattle

Published Online: Oct 27, 2017

Page range: 1007 - 1018

Received: Aug 15, 2016

Accepted: May 12, 2017

DOI: https://doi.org/10.1515/aoas-2017-0006

Keywordsmastitis, somatic cell score, fertility, genetic parameters, Holstein cattle

© 2017 Ludmila Zavadilová et al., published by De Gruyter Open

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Keywords
mastitis, somatic cell score, fertility, genetic parameters, Holstein cattle