By Grant Bolton, Ph.D.
What do a quail farm, mass trapping of mosquitoes, and vector-borne diseases have to do with sustainable livestock feed?
It might be the beginning of a well-funded research project using mosquitoes as a protein source.
The story goes like this: Alexandra Chaskopoulou, Ph.D., and her research team in northern Greece were performing surveillance work on mosquito populations that could potentially vector harmful pathogens like West Nile virus. Using standard light traps in cultivated rice fields, they collected up to 90,000 mosquitoes per trap in just 12 hours.
However, they only need a small sample of these collections to check for pathogens and survey the mosquito population.
So, what do you do with the extra hundreds of thousands of mosquitoes?
A local, backyard quail farmer asked if he could use them to supplement his quail feed. Chaskopoulou obliged and checked in with the farmer later. She learned that the quails had doubled their hatching success rate, and the birds were healthier!
That led Chaskopoulou and her collaborators to study the potential of wild-harvested mosquitoes in poultry feed. Chaskopoulou is a research entomologist at the U.S. Department of Agriculture’s Agricultural Research Service (USDA-ARS) in the European Biological Control Laboratory, based in Thessaloniki, Greece. The results of the pilot study were published this month in the Journal of Economic Entomology.
In mosquito-dense areas, standard light traps, such as the one shown here in a rice field in Greece, can catch huge amounts of mosquitoes—as many as 90,000 mosquitoes per trap in just 12 hours, in one example. A new study shows wild-caught mosquitoes can be used as a protein source in chicken feed. (Photo courtesy of Alexandra Chaskopoulou, Ph.D.)
In mosquito-dense areas, standard light traps can catch huge amounts of mosquitoes—for example, up to 90,000 mosquitoes per trap in just 12 hours, as found by researchers monitoring for vector-borne diseases in cultivated rice fields in Greece, as shown here. A new study shows these wild-caught mosquitoes can be used as a protein source in chicken feed. (Photo courtesy of Alexandra Chaskopoulou, Ph.D.)
“This project was a bit riskier than other projects we had worked on, as there were so many unknown parameters and there was a high possibility that we wouldn’t find any significant impact,” Chaskopoulou says. “However, we recently had won a USDA-ARS competition known as ARSX, which calls for bold, risky research projects that would spark innovation for a healthier, circular agriculture. We knew this would be a new approach to mass trapping and alternative feed ingredients.”
The idea was to use mosquitoes to replace 10 percent of the protein ingredients, which typically come from soybean. “We can potentially turn a farm pest into a farm commodity by upcycling wild insect pests into animal feed,” Chaskopoulou says.
Using insects as feed isn’t a new concept; however, mosquitoes aren’t usually considered at the top of the list of insects to use. That role primarily goes to mealworms, black soldier flies, crickets, or house fly larvae.
However, previous research by Chaskopoulou and her team in 2022 showed that mosquitoes’ nutritional profile is similar to that of common edible insects, especially in terms of protein and fat content.
The new study aimed to see if broiler chickens would feed on mosquitoes, gain weight comparable to a standard feed, and, ultimately, taste good.
The results showed that chickens readily consumed unprocessed mosquitoes, and the treatment group consumed less feed than the control group. Chickens are known to self-regulate their feeding when they feel full, and the added mosquitoes helped achieve that. That meant that the mosquitoes were nutritionally fulfilling the birds’ needs, similar to other insect feed studies. There was no difference in the feed conversion ratio, but since the chickens ate less feed with the mosquito diet, the amount of weight gained was lower. Nonetheless, they exceeded the standard weight specifications of broiler chicken performance for the poultry industry market.
A pilot project replacing 10 percent of standard chicken feed with protein derived from mass-trapped mosquitoes shows farmed chickens readily eat it, with no effects on weight gained or meat quality. In preliminary testing, researchers provided unprocessed mosquitoes to the chickens, which they strongly preferred over their standard soybean-based feed, as shown above.
Following the old adage “You are what you eat,” the researchers wanted to understand if adding mosquitoes to the chickens’ diet would change the quality and taste of the end product.
“To put it simply, visually, the chickens looked very similar to free-range chickens,’ Chaskopoulou says. “They were slightly smaller in size, they had an overall leaner physique, and the color of their meat was a little more yellow and darker.”
The mosquito-fed chicken tended to be a darker meat, while the control chicken was a whiter meat, and this was possibly due to the accumulation of the mosquitoes’ pigments in the chickens’ fat.
Additionally, a taste test was conducted, and the survey found that the mosquito-fed chicken was just as tender as the control chicken, and there were overall no significant preferences for one meat over the other, while thighs from the mosquito-fed group had the highest consumer acceptance.
However, if wild-harvested mosquitoes are potential vectors of diseases like West Nile virus or St. Louis encephalitis, could those pathogens get transferred into the meat?
Luckily, according to the U.S. Centers for Disease Control and the U.S. Food and Drug Administration, there is no evidence that arthropod-borne diseases spread through eating properly handled and prepared poultry meat. That’s great news for growers wanting to feed mosquitoes to poultry.
Chaskopoulou and colleagues also tested the microbial load of the chickens eating wild-harvested mosquitoes, looking for common bacteria like salmonella.
“With regards to animal health and food safety, zero mortality was noted, and important food-borne pathogens like salmonella were not detected,” Chaskopoulou says. “Overall, the microbial analysis showed no differences in the microbial load of the obtained meat both from the control and the mosquito-fed group.”
Chaskopoulou worked with a large group of collaborators for this project, ranging from animal scientists and entomologists to food scientists and nutritionists. Additional work is underway to optimize new mass-trapping devices tailored for insect harvesting and to assess the safety and cost effectiveness of utilizing wild-caught insects as feed ingredients.
This research is another example of exploring environmentally friendly and circular agricultural practices. It spotlights the untapped potential of using wild-harvested pests, which is a double win for those looking to reduce insect pest populations and feed costs on farms.
Grant Bolton, Ph.D., is a freelance writer and voice actor with a Ph.D. in entomology based in western Missouri. Email: grant@boltonvoices.com.
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