By Milliam Murigi
Scientists have developed a new tsetse fly repellent that reduces fly attraction to livestock by up to 90 per cent, offering fresh hope in the fight against livestock diseases across Africa.
The repellent developed by scientists from Kenya Agricultural and Livestock Research Organisation (KALRO) was inspired by the natural defence mechanisms of wild animals such as the waterbuck and has shown remarkable success in reducing tsetse fly attacks on cattle and other livestock.
The breakthrough comes at a time when African countries continue to grapple with losses running into billions of shillings annually due to diseases transmitted by tsetse flies.
“Years of studying the behaviour of the insects revealed that while cattle are highly attractive to tsetse flies, waterbucks are rarely bitten despite sharing the same habitats, ” said Paul O Mireji, one of the researchers involved in the project.
The discovery prompted scientists to investigate the animal’s body odours, leading to the identification of several naturally occurring compounds that repel the insects.
Through laboratory analysis, researchers isolated and synthesized the compounds, including one known as delta-octalactone, which emerged as a key ingredient in the new repellent.
Tests conducted using wind tunnels and artificial odour dispensers showed that the compounds significantly reduced the attraction of tsetse flies. When combined with other chemical components, the repellent reduced fly attraction by up to 90 per cent.
“The findings demonstrate that it is possible to exploit natural animal defences to protect livestock from disease vectors,” he said.
Unlike conventional insecticides, the repellent does not kill the flies but instead prevents them from locating animals, reducing the chances of disease transmission while minimizing environmental impacts.
Scientists believe the technology could be incorporated into livestock collars, ear tags and slow-release dispensers placed around cattle enclosures, providing farmers with a practical and affordable means of protecting their animals.
Tsetse flies infest nearly 10 million square kilometres across sub-Saharan Africa and transmit trypanosomes, parasites that cause nagana in livestock and sleeping sickness in humans.
The diseases reduce milk production, weaken animals, lower fertility rates and often result in death, posing a major obstacle to livestock development and food security.
Livestock experts say the new repellent could be a game-changer, particularly for pastoral communities that rely heavily on cattle, goats and sheep for their livelihoods.
If widely adopted, the innovation could help improve animal health, increase productivity and reduce the economic burden associated with tsetse-borne diseases across the continent.
Researchers are now working with partners to scale up production and make the technology available to farmers in affected regions.
