Progeny tested sires compared with pedigree selected young sires

Area of Science:

• Animal Science
• Dairy Cattle Genetics
• Reproductive Technologies

Background:

• Artificial insemination (AI) is crucial for genetic advancement in dairy cattle.
• Evaluating young sires within AI programs is essential for identifying superior genetic merit.
• Selection strategies impact the genetic gain achieved in dairy populations.

Purpose of the Study:

• To compare the milk production performance of progeny from young AI sires versus naturally proven sires.
• To assess the impact of sire, dam, and maternal grandsire selection on milk yield in Holstein cows.
• To evaluate the effectiveness of pedigree indices in predicting young sire performance.

Main Methods:

• Analysis of first lactation records from 109,589 Holstein cows across 1,978 herds.
• Comparison of progeny performance based on sire's genetic merit (Predicted Difference) and pedigree indices.
• Inclusion of selection differentials for sires, dams, and maternal grandsires in the analysis.

Main Results:

• Progeny of AI-proven sires produced 84 kg more milk and 2.4 kg fat than progeny of young sires within the same herd-year-season.
• Progeny of young sires outperformed daughters of naturally proven sires by 103 kg milk.
• Pedigree indices for young sires, including sire, dam, and maternal grandsire, averaged 347 kg milk and 11.8 kg fat.

Conclusions:

• Young sires utilized in AI sampling programs demonstrate significant genetic potential for milk yield.
• AI programs effectively identify genetically superior sires, leading to improved progeny performance.
• Selection based on comprehensive pedigree information contributes to enhanced genetic gain in dairy breeding.