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Genetic relationships between selection for growth and reproductive effectiveness
1Department of Poultry Science, The Pennsylvania State University, University Park 16802, USA. gfb1@psu.edu
Poultry Science
|March 25, 1999
Summary
Genetic selection for poultry growth impacts reproduction differently across ages. An in vitro sperm binding assay aids in improving fertility without compromising growth performance in meat-type chickens.
Area of Science:
- Animal Genetics
- Poultry Science
- Reproductive Biology
Background:
- The poultry industry prioritizes genetic improvement for growth in meat-type birds.
- Understanding genetic relationships between growth and reproduction is crucial for sustainable breeding programs.
Purpose of the Study:
- To investigate the genetic correlations between growth at different ages and reproductive traits in poultry.
- To evaluate the utility of an in vitro sperm binding assay for genetic selection in poultry breeding.
Main Methods:
- Utilized data from a double, divergent selection experiment in meat-type poultry lines.
- Analyzed genetic relationships between growth parameters (e.g., EGR14, EGR42) and reproductive traits.
- Employed an in vitro sperm binding assay to assess rooster fertility and its genetic correlation with reproductive phenotypes.
Main Results:
- Growth to different ages exhibits distinct genetic architectures; growth rate from 14 to 42 days (EGR14/42) negatively correlates with reproductive traits.
- Fertility shows a positive correlation with early growth (EGR14) but a negative correlation with later growth (EGR42).
- The in vitro sperm binding assay is highly correlated with fertility (additive genetic correlation of 0.75) and can be used in selection programs.
Conclusions:
- Evaluating growth as a nonlinear phenomenon is essential in poultry genetics programs.
- Selecting against poor sperm binding in roosters can enhance fertility and chick production without negatively impacting progeny growth.
- The in vitro sperm binding assay offers a practical tool for improving reproductive efficiency in poultry breeding.
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