Breed differences in the response of young beef bulls to electro-ejaculation

Area of Science:

• Animal Science
• Reproductive Biology
• Veterinary Medicine

Background:

• Electro-ejaculation is a common method for semen collection in beef bulls.
• Understanding breed-specific responses is vital for improving collection efficiency and animal welfare.

Purpose of the Study:

• To assess breed differences in electro-ejaculation success and adverse reactions in young beef bulls.
• To identify potential correlations between breed, reaction severity, and collection failure.

Main Methods:

• Conducted 702 electro-ejaculation attempts on young bulls from Brahman, Africander, Shorthorn, and crosses using a Watson Transtimulator.
• Recorded voltages for sperm-free and sperm-rich samples, bull reactions, erection, collection success, and collapse events.

Main Results:

• Africander and Brahman crosses exhibited significantly higher proportions of severe reactions and electro-ejaculation failures.
• No significant breed differences were observed in erection achievement or failure to collect an assessable ejaculate.
• Shorthorn breed group showed the highest incidence of collapse during stimulation (12.8%).

Conclusions:

• Breed significantly influences the severity of reaction and failure rates during electro-ejaculation in beef bulls.
• Africander and Brahman-derived breeds require careful handling due to higher susceptibility to adverse reactions.
• Further research may optimize electro-ejaculation protocols tailored to specific beef breeds.