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Short communication: Genetic variation in estrus activity traits
1Department of Genetics and Biotechnology, Faculty of Agricultural Sciences, Aarhus University, Tjele, Denmark. Peter.Lovendahl@agrsci.dk
Journal of Dairy Science
|August 25, 2009
Summary
Genetic variation in estrus traits was analyzed in dairy cows using electronic activity tags. Results indicate potential for genetic selection to improve fertility by targeting activity patterns.
Area of Science:
- Animal Genetics
- Reproductive Biology
- Dairy Science
Background:
- Estrus detection is crucial for reproductive management in dairy herds.
- Traditional methods for estrus detection can be labor-intensive and inaccurate.
- Electronic activity tags offer a novel approach to monitor estrus-related behaviors.
Purpose of the Study:
- To investigate genetic variation in estrus traits measured by electronic activity tags.
- To estimate heritability of estrus-related activity traits in different dairy cattle breeds.
- To assess the potential of activity traits for genetic selection to improve fertility.
Main Methods:
- Utilized hourly activity data from electronic tags in Holstein, Jersey, and Red Dane cows.
- Included both virgin heifers and lactating cows across multiple parities.
- Analyzed 3,284 high-activity episodes indicative of estrus.
Main Results:
- Detected significant genetic variance for 'days to first high activity' with a heritability of 0.18 +/- 0.07.
- Heritability for the duration of increased activity (0.02-0.08) and activity level (0.04-0.08) was low.
- Predicted first estrus post-calving at 39 days for Red Danes, 44 for Holsteins, and 45 for Jerseys.
Conclusions:
- Estrus traits measured by activity tags exhibit genetic variation, particularly in the timing of first estrus.
- Activity traits show higher heritability compared to traditional fertility traits derived from artificial insemination data.
- These findings suggest that estrus activity traits can be valuable tools for genetic selection aimed at enhancing dairy cattle fertility.
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