MNN Galleries

7 pudgy pets that should lay off the kibble

By: Catie Leary on Feb. 23, 2011, 11:55 a.m.
Overweight mouse called Louie

Photo: YawningDog/Flickr

4 of 8

Leptin-lacking Louie

As with any animal, some cases of obesity in pets can be attributed to genetics. This rotund mouse, Louie, is overweight because she lacks a gene that produces leptin, a protein that sends a message to the brain that essentially says, "I'm full."

Leptin was first discovered in 1994 by molecular geneticist Jeffrey M. Friedman through the study of obese mice. Since then, efforts have been made to link this genetic discovery to solutions for combating the obesity epidemic affecting humans.