No sacred cows, all must wear collars

By Maore Ithula

Sub-Saharan pastoralists could soon outwit the bloodsucking insects, tsetse flies, and prevent them from infecting their livestock with nagana.

A Kenyan researcher based at the International Centre for Insect Physiology and Ecology (ICIPE) has developed the technology, which makes this peaceful co-existence possible.

Dr Rajinder Saini, who is an insect behaviour and dermatology specialist says the chemicals developed at the Kasarani-based Duduville Institute will be tied in dispensers mounted on the special collars to be worn by cattle around the neck.

Tsetse flies are large biting flies that inhabit much of mid-continental Africa between the Sahara and Kalahari deserts.

They live by feeding on the blood of boned animals and are the primary biological vectors of trypanosomes, which cause sleeping sickness in humans and nagana, technically known as trypanosomiasis, in animals.

Saini explains there are two compounds his team had identified and were trying to establish which of the two is most cost-effective for pastoralists and people living in tsetse-prone areas.

Cocktail Of Repellents

One of the compounds is a synthetic chemical isolated in ICIPE laboratories, while the other is derivative from a cocktail of natural repellent chemicals occurring in waterbucks bodies which, when emitted, repel tsetse flies.

Zebras, says Saini, possess similar chemicals in their bodies, but attempts to extract it flopped because the animals are difficult to handle in captivity.

The development will save pastoralists in sub-Saharan Africa millions worth of cattle lost to nagana.

Further, approximately 500, 000 people suffer from sleeping disease every year in 36 countries of sub-Saharan Africa.

Kenya has an estimated 13 million cattle, out of which 23 per cent are threatened by the blood-sucking fly. In total, Africa loses three million animals to nagana every year.

Says Saini: "The losses are phenomenal. Three million dead cattle is 500,000 tonnes of condemned meat and one million tonnes of milk. Ironically, this is the loss incurred by the very poorest communities in the continent." Besides having no naturally occurring repellents in their bodies, the smell of cattle urine is also very attractive to tsetse flies, says the researcher.

The scent emitted by waterbucks that helps keep the fly away is a cocktail of four chemicals that include fatty acids, ketones, phenols and lactones.

Saini says the search for chemicals that can repel the insects began three years ago after it was realised that fixed traps were no longer effective because of adverse weather patterns caused by climate change, forcing pastoralists to wander far away in search of pasture and water.

Mobile Technology

"Because pastoralists are extremely mobile, we realised the futility of the fixed tsetse fly traps and embarked on a search for a technology that is also mobile."

The search for the synthetic chemical led Saini and his team to a complicated chemical he refers to as creosol (2methoxy-4-mythl-phenol). He has already patented this compound.

Now that the search is successful, he says: "We are organising logistics for manufacturing stage of the chemicals."

Saini who is also a principal scientist and head of animal health division and tsetse fly programme leader at Duduville says with $2million (Sh157.5 million) grant from European Community, production of the collars is set to start.

He says it costs about $25 (Sh2, 000) to develop one complete prototype collar but in about three years, the cost should come down to about three US dollars (Sh240) per collar. He is confident his technology could save Africa $40 million (Sh3.2 billion) on drugs annually.

ICIPE has partnered with Kenya Industrial Development Research Institute (KIRDI) for mass production of the collars as the researchers can only make prototypes.

The team developed prototypes of the collar and dispenser that have been used for trials in Shimba Hills in Coast, Maasai Mara and Ngurumani in Kajiado. The efficacy of the technique is 80 per cent, and can be improved. The trial recommended all cattle must wear collars to stay alive and escape tse tse fly attacks.