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Biotech Company Sterilizes Rats Without Harmful Health Impacts

Scientist Loretta Mayer has discovered how to make a mouse menopausal. The research is now being used to sterilize rats and dogs.
Scientist Loretta Mayer has discovered how to make a mouse menopausal. The research is now being used to sterilize rats and dogs.

By Laurel Morales

http://stream.publicbroadcasting.net/production/mp3/knau/local-knau-953696.mp3

Flagstaff, AZ – Flagstaff scientist Loretta Mayer has developed a chemical that when eaten by female rats makes them menopausal. That's when there aren't any eggs left in their ovaries.

MAYER: Their eggs are reabsorbed by a natural process. The active ingredient we use accelerates that process so they are no longer reproductive. (0:10)

Mayer and her team of researchers have disguised the sterilant in rat bait.

(sound of rat bait) There's a Tupperware container full. And they're attracted to this because it's tasty to them? It's just like French fries. (0:09)

But Mayer didn't set out to solve rat problems. She had hoped to find a cure for heart disease in women.

MAYER: I had a really good friend who was kind of like a mom to me. She was in her early 50s and dropped dead of a heart attack. (0:07)

Mayer learned that little heart disease research existed for post menopausal women. What she needed was post menopausal mice to study. So she and University of Arizona scientist Pat Hoyer discovered how to do it chemically.

MAYER: We call it "mouse-o-pause." (0:02)

Researchers around the world were intrigued by the wider benefits of their heart disease studies.

MAYER: Our colleagues in Australia called and said we have a huge responsibility to the declining food sources in Asia. (0:10)

Rats, which produce as many as five litters a year, wipe out an inordinate amount of rice in southeast Asia -- anywhere from 10 to 50 percent of the crop. Nearly half of the world's population relies on rice to survive. So in 2002 Mayer started a biotechnology company called SenesTech. Today it is in the process of manufacturing large amounts of ContraPest, their rat sterilizer.

SenesTech's Timothy Vail is on his way to Laos to set up a manufacturing facility.

VAIL: Up until now we've been using kitchen aids and little food dehydrators. This is our first major foray into a full manufacturing experiment. (0:10)

Here in the United States the New York City Transit Authority heard about ContraPest and became interested.

MAYER: We'll be addressing the rats that ride the subways in New York that you can put a saddle on. (0:06)

Rats have ruled the New York subway system for years causing a health hazard.

A veterinarian on the Navajo Reservation who was tired of euthanizing so many diseased dogs called up Mayer and told her about the "rez dog" problem. So SenesTech developed ChemSpay to sterilize dogs and cats. SenesTech still must obtain permits to use the product in the U-S.

They've had an easier time jumping regulatory hurdles off shore.

Mayer points to a world map on the wall where different colored tacks mark where they are working.

MAYER: We have a group in York in the UK, Indonesia, Mumbai in India, New Zealand, Australia we call Flagstaff the mother ship. (fade out) (0:08)

They've recently added a tack to Tibet where rabid dogs are a major problem. So Mayer and her team traveled for 50 hours to the remote village and met with his holiness the Dalai Lama himself.

MAYER: The overarching driver for their belief system is the end of suffering. They do not wish any living being to suffer so euthanasia is not a practice they employ to control these disease vectors. (0:15)

Soon SenesTech will distribute ChemSpay along with rabies vaccinations to dogs in Tibet.

Mayer says someday when she retires she'll go back to working in a lab on a cure for heart disease in women. In the meantime her company has plans for grain eating rats in Yuma and for plagued rodents in Madagascar.
In Flagstaff I'm Laurel Morales.