Identifying Subfertile Bulls for Better Breeding

N. Johnson. E. Balla, T. Wood and V. Martinez
4 March 2025

Reproductive success is at the heart of sustainable livestock production. However, subfertile bulls pose a hidden challenge, leading to reduced conception rates and economic losses. Traditional semen quality assessments often fail to detect subtle deficiencies in motility that impact fertility. Dyneval’s research, as outlined in the recent case study, demonstrates how time-dependent semen analysis can revolutionise the identification of subfertile bulls, ensuring optimal breeding decisions.

The Challenge: Detecting Hidden Subfertility

Artificial insemination (AI) relies on semen quality to achieve high conception rates. While traditional assessment methods such as gross motility and progressive motility offer a snapshot of sperm movement, they do not capture the crucial time-dependent changes that determine sperm longevity and fertilization potential. This limitation leaves farmers, veterinarians, and genetics companies with incomplete data, potentially allowing subfertile bulls to remain in breeding programs. ‘I’m interested in learning more about how semen lifetime analysis can help us identify potential health or genetic issues in bulls’, commented Rodrigo de Moraes Rodrigues (New Business Manager, Alta Genetics Brazil).

The Dyneval Approach: Precision Motility Analysis

Dynescan semen analyser provides an advanced solution by analysing semen progressive motility over time. The study revealed that semen samples from bulls with lower fertility showed a significant decline in motility within just 15 minutes despite having passed full Veterinary Assessment and morphological examination. In contrast, semen from highly fertile bulls retained motility for extended periods, demonstrating higher viability for fertilisation.

By leveraging time-dependent progressive motility analysis, the Dynescan semen analyser enables precise differentiation between bulls with high and low fertility potential. This empowers AI technicians, veterinarians, and genetics companies to make data-driven decisions when selecting sires, leading to improved reproductive outcomes.

The Impact: Enhanced Fertility and Productivity

Higher Conception Rates – By identifying bulls with superior semen longevity, producers can optimise insemination strategies and improve pregnancy rates.

Reduced Economic Losses – Early detection of subfertile bulls prevents wasted resources on ineffective breeding efforts.

Sustainable Livestock Management – Maximising fertility supports efficient breeding programs, reducing methane emissions to lower the carbon footprint associated with reproductive inefficiencies.

Looking Ahead: A New Standard in Semen Assessment

The ability to measure semen motility over time marks a paradigm shift in fertility management. Dyneval’s research reinforces the need for advanced analysis techniques to ensure every straw of semen used in AI contributes to reproductive success. As this technology gains adoption, it will redefine industry standards for semen quality evaluation, delivering benefits across the entire livestock sector.