Evaluation of systematic breeding programs for lactating dairy cows: a review

Area of Science:

• Veterinary Science
• Animal Reproduction
• Dairy Management

Background:

• Effective dairy herd reproductive management relies on accurate estrus detection and timely insemination.
• Larger herd sizes often result in reproductive inefficiencies and reduced farm profitability.
• Estrus synchronization using pharmacological control enhances reproductive efficiency and streamlines breeding programs.

Purpose of the Study:

• To evaluate the effectiveness of systematic breeding programs for dairy herd reproductive management.
• To compare the reproductive performance of Targeted Breeding and Ovsynch protocols with traditional methods.

Main Methods:

• Targeted Breeding: A series of three PGF2 alpha injections at 14-day intervals, administered weekly to cows past a target date, followed by estrus detection and artificial insemination (AI) or fixed-time AI.
• Ovsynch: A GnRH injection, followed 7 days later by PGF2 alpha, then a second GnRH injection 36–48 hours after PGF2 alpha, culminating in timed AI.
• Both protocols facilitate organized, herd-wide artificial insemination at first service.

Main Results:

• Both Ovsynch and Targeted Breeding protocols have demonstrated improved reproductive performance.
• Systematic breeding programs offer convenience and efficiency in managing artificial insemination for entire herds.
• These methods provide a methodical approach to reproductive management, moving beyond individual cow observation.

Conclusions:

• Estrus synchronization protocols like Ovsynch and Targeted Breeding are effective in improving dairy herd reproductive efficiency.
• Systematic breeding programs offer a practical and efficient alternative to traditional estrus detection methods.
• Implementing these organized approaches can enhance overall dairy farm profitability through improved reproductive outcomes.