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Updated: Jan 18, 2026
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Protocol for Assessing the Relative Effects of Environment and Genetics on Antler and Body Growth for a Long-lived Cervid
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Estimates of Variance Components and Genetic Parameters for Weekly Weight in Juvenile Dairy Goats Using Random
Chrilukovian B Wasike1, Ruth Wambui Waineina2, Kiplangat Ngeno3
1Livestock Efficiency Enhancement Group (LEEG), Department of Animal and Fisheries Sciences, Maseno University, Maseno, Kenya.
Summary
Improving dairy goat growth is key for future productivity. This study estimates genetic parameters for juvenile goat growth, showing potential for selective breeding based on early weight measurements.
Area of Science:
- Animal Genetics
- Quantitative Genetics
- Livestock Science
Background:
- Dairy goat improvement programs prioritize milk and fertility over growth traits.
- Juvenile growth performance significantly impacts mature reproductive success.
- Understanding genetic parameters for growth is crucial for breeding programs.
Purpose of the Study:
- To estimate variance components and genetic parameters for juvenile dairy goat growth.
- To provide data for inclusion in national dairy goat improvement programs.
- To assess the potential for selective breeding based on growth traits.
Main Methods:
- Collected 4072 weekly weight records from 453 goats (Saanen, Toggenburg, Alpine, crossbreds).
- Applied univariate random regression analysis including direct additive, maternal genetic, and permanent environmental effects.
- Estimated variance components and genetic parameters across the growth trajectory (1-16 weeks).
Main Results:
- Phenotypic, additive genetic, maternal genetic, and permanent environmental variances increased with age.
- Variance ratios indicated significant additive genetic (0.015-0.469), maternal genetic (0.097-0.204), and permanent environmental (0.407-0.641) influences.
- High positive correlations were observed for additive genetic and maternal genetic effects across weekly weights.
Conclusions:
- Sufficient genetic variance exists in weekly weights for effective selective breeding in dairy goats.
- Early weekly weights can be used for selection to improve later growth performance due to high additive genetic correlations.
- Incorporating growth trait data into breeding programs can enhance overall dairy goat productivity.
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