Hometop nav spacerAbout ARStop nav spacerHelptop nav spacerContact Ustop nav spacerEn Espanoltop nav spacer
Printable VersionPrintable Version     E-mail this pageE-mail this page
United States Department of Agriculture Agricultural Research Service
Search
 
 
 
National Programs
International Programs
Find Research Projects
The Research Enterprise
Office of Scientific Quality Review
Research Initiatives
 

Title: GENETIC EVALUATION OF STILLBIRTH IN UNITED STATES HOLSTEINS USING A SIRE-MATERNAL GRANDSIRE THRESHOLD MODEL

Authors

Submitted to: World Congress of Genetics Applied in Livestock Production
Publication Type: Proceedings
Publication Acceptance Date: May 6, 2006
Publication Date: August 13, 2006
Citation: Cole, J.B., Wiggans, G.R., Van Raden, P.M. 2006. Genetic evaluation of stillbirth in United States Holsteins using a sire-maternal grandsire threshold model. 8th World Congress of Genetics Applied in Livestock Production. Communication 01-28.

Interpretive Summary: A sire-maternal grandsire (MGS) threshold model was used for genetic evaluation of stillbirth in US Holsteins. Data consisted of almost 7.5 million records, and over 41,000 AI bulls received evaluations. The model included effects of herd-year, year-season, parity-sex, sire, birth year group of sire, MGS, and birth year group of MGS, and dystocia score. Herd-year, sire, and MGS were random effects. Mean PTA, expressed as expected percentage of stillbirths in heifers, were 12.47 and 14.28 for direct and maternal stillbirth, respectively. Reliabilities for the direct and maternal effects averaged 0.53 and 0.52, respectively. Dystocia scores had a larger effect on stillbirth than year-season, sire, or MGS effects. Correlations among US and Interbull stillbirth solutions on the underlying scale for bulls with at least 90% reliability ranged from 0.63 to 0.90 across countries for direct SB and 0.69 to 0.96 for maternal SB, indicating that results were generally consistent with those from other countries. There was no evidence of a consistent genetic trend. More complete recording of stillbirth scores would improve reliabilities and possibly allow for evaluations of other breeds.

Technical Abstract: A sire-maternal grandsire (MGS) threshold model was used for genetic evaluation of stillbirth in US Holsteins. Data consisted of almost 7.5 million records, and over 41,000 AI bulls received evaluations. The model included effects of herd-year, year-season, parity-sex, sire, birth year group of sire, MGS, and birth year group of MGS, and dystocia score. Herd-year, sire, and MGS were random effects. Mean PTA, expressed as expected percentage of stillbirths in heifers, were 12.47 and 14.28 for direct and maternal stillbirth, respectively. Reliabilities for the direct and maternal effects averaged 0.53 and 0.52, respectively. Dystocia scores had a larger effect on stillbirth than year-season, sire, or MGS effects. Correlations among US and Interbull stillbirth solutions on the underlying scale for bulls with at least 90% reliability ranged from 0.63 to 0.90 across countries for direct SB and 0.69 to 0.96 for maternal SB, indicating that results were generally consistent with those from other countries. There was no evidence of a consistent genetic trend. More complete recording of stillbirth scores would improve reliabilities and possibly allow for evaluations of other breeds.

   
 
 
Last Modified: 05/24/2013
ARS Home | USDA.gov | Site Map | Policies and Links 
FOIA | Accessibility Statement | Privacy Policy | Nondiscrimination Statement | Information Quality | USA.gov | White House