Menopausal rats could prove solution to rodent problem

Loretta Mayer speaks about rat sterilization.

The invention has proven it can successfully reduce rodent populations, 
but a cash injection is needed to scale it up

An Arizona-based company has developed a rat-control product that could spell the end of the adage, if you have one rat, there are probably more.

“I call it rat-o-pause,” SenesTech CEO Loretta Mayer told a crowd at the annual Agri Innovation Forum in Winnipeg last month, explaining the compound her company has developed essentially causes female rats to prematurely enter menopause.

The result? No more baby rats. And as a brown rat can produce five to seven litters of seven to 14 babies each year, and their offspring will start doing the same within four months — shutting down their reproductive cycle can have impressive results.

“The state of the art right now is to kill them, and… yes, that strategy will work, but it’s not sustainable,” she said. “The reason it’s not sustainable — scientists have known this for years — is because of the rebound effect.”

Once you clear one area of rats, neighbouring rat populations simply move in to capitalize on the sudden increase in available resources, Mayer said.

However, if you decrease a rat population more slowly, through attrition and natural death without reproduction, remaining rats become territorial, preventing new rodent hordes from encroaching. The rodent population is reduced to a tiny fraction of its previous level, and there is no risk of a rebound effect.

Using poison to control rat populations also carries the risk that other species, including humans, can be affected by the poison, Mayer said. She noted 16,000 children accidently ingest raticides each year in the U.S. In developing countries the risk of inadvertently ingesting rat poison is even higher.

So far the SenesTech compound has been tested in the New York City subway system, as well as in hog barns in North Carolina, where swine dysentery is spread by the rodents.

“I don’t care how many times you shower in and out of those facilities, it’s going to spoil your day when you find a rat that is carrying that disease,” Mayer said.

Granaries, and other food storage areas could also benefit from a rodent sterilization program.

Although rats may be most closely associated with times past, Mayer notes current food production levels are working in favour of a growing rat population.

“On behalf of rodents everywhere, I would like to say thank you for increasing your crop yield, it’s a banquet for rodents,” she said.

But the former cardiac researcher, who first developed the rodent sterilizer for a research project, is still searching for funding and partnerships to get the novel compound to market.

“We are looking for partners, global partners who can help us get this technology out into the global market,” the CEO said, adding the company is currently looking for about $10 million in equity capital.

She hopes the uniqueness of the rodent control product will draw in interested investors.

“We’re a very odd company,” Mayer said. “We accelerate that natural process of aging the gonad.”

The compound developed by the researcher also breaks down in soil and water into two harmless compounds, allaying fears of unintended consumption.

“This compound does not work in any species above a non-human primate,” she said.

About the author


Shannon VanRaes is a journalist and photojournalist at the Manitoba Co-operator. She also writes a weekly urban affairs column for Metro Winnipeg, and has previously reported for the Winnipeg Sun, Outwords Magazine and the Portage Daily Graphic.



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