Rats facing NAU spay chemical

[Source:CYNDY COLE, Arizona Daily Sun Staff Reporter] - As the United Nations warns of a global crisis and residents of more than a dozen countries riot because of rapidly increasing food prices, rice-field rats in Southeast Asia are chowing down in the world's rice bowl.

The rodents, able to produce 600 offspring from one pair in a few months, have sometimes eaten one-third of the rice crops and are raising a famine scare in India. General anti-coagulant poisons knock back the populations, but they always rebound.

"With the food shortages that are starting to erupt, this is huge," said Cheryl Dyer, researcher and ovarian physiologist at Northern Arizona University.

She and NAU scientists Loretta Mayer and Timothy Vail have helped create a product that could knock back the rat population, and nonsurgically sterilize female dogs, cats and other vertebrate pest species.

The idea might someday replace surgeries to spay domestic pets, help control packs of rabid dogs in Africa -- or find popularity in Spain, where pied pipers tried last year to drive crop-eating rodents from their fields with the use of flutes.

And if rice-growing countries were to spay rats and save 10 percent more of their crops per year, it would be enough to feed 380 million people.

The product came from the discovery that an industrial compound found in the plastics industry could accelerate the aging process in rodents, but affect no other part of the body.

"I saw it and said, 'That's my model for menopause,'" Mayer said.

Pharmaceutical companies had been testing drugs for human on mice and rats with their female reproductive organs removed.

This compound kept the organs intact, to cause chemical sterilization, more closely simulating menopause in women.

In short, it created a better lab mouse.

And the compound is short-lived, posing less environmental and food-chain risk than the anticoagulants now used to poison rice-field rats and whatever other animals consume the bait.

Rice-producing countries are currently spending more than $1 billion annually on poison, Mayer said, while chemists must continually rework the poisons to keep ahead of animal resistance.

This chemical compound, named ContraPest, is to be used in the rice fields of Java this summer by the International Rice Research Institute.

It has already been used to chemically spay 170 dogs from the Navajo Nation that were adopted to homes. Mayer and Dyer are animal lovers who say this is a good way to restore balance in animal populations gone haywire.

Commercial licensing for pet spaying is probably at least two years away, they say.

Mayer is president and Dyer is chief researcher for SenesTech, a Flagstaff biotechnology company founded in 2002 to improve women's health and control feral animal populations.