GAINESVILLE, Fla. — Most people try to avoid feeding hungry mosquitoes, but for some medical researchers it’s a different story.

Lab-raised mosquitoes are used in studies investigating how the blood-sucking insects transmit viruses and parasites. Those mosquitoes must be cared for and that means providing female specimens with blood, which supplies protein they need to produce eggs.

Some labs allow their mosquitoes to feed the old-fashioned way, by biting live animals. But to save time, money and effort, other labs give the insects packaged animal blood, which may contain additives or lack components removed by processing.

Scientists with the University of Florida’s Institute of Food and Agricultural Sciences have found that different types of blood influence the quantity of eggs a female mosquito produces, and the likelihood those eggs hatch.

That’s important to know, because mosquito researchers typically want to know how closely their lab experiments mimic real-world conditions.

The study, conducted at UF’s Florida Medical Entomology Laboratory in Vero Beach, was published in the June issue of Journal of Vector Ecology.

To feed the mosquitoes, scientists used four blood sources: live chickens, chicken blood with an anticoagulant added, beef blood with an anticoagulant added, and beef blood with its main clotting protein removed. Female mosquitoes were divided into groups and most groups were offered only one blood source throughout the study.

One example of the variability the scientists found: Among mosquitoes offered beef blood without the clotting protein, only 31 percent chose to feed; among those that fed, 40 percent laid eggs and 70 percent of those eggs hatched. In contrast, 61 percent of the mosquitoes offered a live chicken chose to feed, 46 percent of those that fed laid eggs, and 83 percent of those eggs hatched.

Lead author Stephanie Richards, now an assistant professor at East Carolina University, said the results show that mosquito researchers should carefully consider feeding methods when designing experiments. She also suggests more research might be needed to determine whether different blood sources may affect mosquitoes’ ability to transmit viruses.

Contacts

Writer: Tom Nordlie, 352-273-3567, tnordlie@ufl.edu

Source: Stephanie Richards, 252-328-2526, richardss@ecu.edu

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