By vet Rob Simmons
When discussing fertility, it is easy to become distracted by the latest breeding indexes, exciting new genetics, sexed semen, IVF programmes and embryo transfer. Whilst these technologies can undoubtedly accelerate genetic progress, the reality is that no breeding programme can outperform the basic management of the animals involved.
Whether your goal is to achieve more cows in calf through artificial insemination, improve embryo transfer pregnancy rates, or simply maximise the performance of a stock bull, the foundations of fertility remain remarkably similar.
Nutrition is perhaps the most important factor. Cows and heifers need sufficient energy, protein and minerals to maintain normal reproductive function, but fertility is often affected long before obvious clinical signs appear. Body condition that is either too low or too high can reduce conception rates, increase early embryonic loss and delay the return to normal cycling after calving. Sudden changes in diet can also have a significant impact. Fertility is generally improved by consistency and steady nutritional management rather than short-term attempts to "feed fertility in" immediately before breeding.
Good fertility also starts long before the breeding season itself. Heifers need to achieve appropriate growth rates in order to reach puberty at the correct age, while cows require a successful transition through the calving period. Problems such as difficult calvings, retained cleansings, uterine infections and severe negative energy balance can all reduce fertility for months afterwards. By the time breeding begins, many of the factors influencing conception have already been determined.
Health status is another crucial consideration. Infectious diseases such as BVD, leptospirosis and IBR can all have major effects on reproductive performance. Vaccination programmes, biosecurity measures and prompt investigation of fertility problems remain some of the most cost-effective investments livestock farmers can make. Fertility is often the first area to suffer when disease is circulating within a herd, even when other clinical signs are relatively subtle.
Observation and stockmanship are equally important. In AI programmes, accurate heat detection remains essential despite advances in activity monitoring technology. In embryo transfer programmes, selecting suitable recipients and ensuring they are synchronised correctly depends upon careful attention to detail. Technology can help identify opportunities, but it cannot replace good stockmanship and regular observation of cattle behaviour.
Stress is another frequently overlooked factor. Moving animals, regrouping, transport, overcrowding and abrupt management changes can all influence reproductive performance. The period immediately before and after breeding is particularly important. Providing adequate space, comfortable housing and a stable social environment helps animals direct their energy towards reproduction rather than adaptation to new challenges.
Finally, realistic expectations are important. Fertility is a biological process rather than a manufacturing process. Even with excellent management, not every insemination creates a pregnancy and not every embryo transfer results in a calf. The aim should be to consistently provide animals with the best possible conditions to express their reproductive potential.
Advanced reproductive technologies offer exciting opportunities for modern livestock farming, but they do not replace the fundamentals. Whether you are breeding your next generation of dairy replacements, producing pedigree beef animals or running a large embryo transfer programme, success still relies on the same core principles: healthy cattle, good nutrition, strong biosecurity, low stress and excellent stockmanship.
Get those basics right, and every breeding strategy, from natural service through to IVF, has a much greater chance of success.