New Estrogen-Free Technique Could Transform Cattle Breeding

Researchers at the University of Saskatchewan have developed a new method of cattle reproduction that could improve breeding efficiency without the use of estrogen-based hormones.

The study, led by Dr. Jaswant Singh of the Western College of Veterinary Medicine, introduces the use of a drug called Cetrorelix to control ovulation in cattle. The findings were published in the journals Biology of Reproduction and Theriogenology after more than 25 years of research.

Earlier methods relied on the hormone estradiol to synchronize ovulation, allowing farmers to carry out fixed-time artificial insemination. However, concerns in Europe and the United States over the use of estrogen in food-producing animals led researchers to seek alternatives.

The new approach uses Cetrorelix, a drug commonly used in human fertility treatments. Researchers found it can trigger a new follicular wave in cattle, a key step needed to control ovulation. Tests show the method performs as effectively as the earlier estradiol-based system.

The research team says the method works across different stages of the cow’s reproductive cycle and does not require additional labour. It may also reduce the time farmers spend monitoring animals.

The University of Saskatchewan has secured a patent for the protocol and is working with a pharmaceutical company to bring the method to market for use in cattle and other livestock.

Researchers say the development could help farmers better manage breeding, improve herd health, and increase productivity through more controlled use of artificial insemination.