Scientists ID chemicls that may help fight cattle disease

NAIROBI, March 12 (Xinhua) -- Researchers have identified chemicals in odor from animal dungs that help breeding of stable flies, a discovery that could help fight trypanosomiasis, a deadly cattle disease.

The researchers at the Nairobi-based International Center of Insect Physiology and Ecology (ICIPE), in collaboration with South Africa's University of Pretoria, said Tuesday the chemicals could be used in baiting traps to attract pregnant stable flies, hence reducing populations.

"Stable flies are a serious challenge to livestock and people across the world in general, and in Africa specifically. These blood-sucking insects transmit various pathogens, for example trypanosomes, that cause the deadly trypanosomiasis," said Merid Getahun, a scientist at ICIPE, who led the study.

Getahun noted that besides causing the disease, the painful bites of the flies also lead to loss of blood, reduced weight and poor lactation in afflicted livestock, severely diminishing productivity.

The study demonstrates that even when numerous choices are available, stable flies have a strong preference to lay their eggs in donkey and sheep dung.

"We found these two types of droppings to have better nutrient content that improves the development of the eggs that hatch faster, while the young ones gain weight quicker, leading to more robust flies," explained Bernard Baleba, another ICIPE scientist.

The researchers discovered that the flies are guided by two compounds known as beta citronellene and carvone, found in donkey dung and sheep dung, respectively.

"These results have great potential. These chemicals could be used in baiting traps to attract pregnant stable flies, hence reducing populations from one generation to another," Baleba said.

Dan Masiga, head of ICIPE's Animal Health Theme, said any tool that improves control of vectors of animal diseases enhances the potential of African farmers' productivity.

"This research is especially exciting because we can work in partnership with industry to translate into technologies and disseminate them to communities," Masiga said.