Short Takes: 08/03

Finding new ways to help overweight cats; fungi and sinus infections

Human Help for Dieting Felines
A feeding study underway at the Cornell University College of Veterinary Medicine is testing possible new prescription diets for obese felines. The tubby pets  human companions are also under the microscope, as researchers examine the temptation to feed too much.

Well be asking what the cat does when its hungry, says Katherine Houpt, VMD, PhD, and director of the colleges Animal Behavior Clinic. Does it meow all night? Scratch at the cupboard? Bite people? Or do the cats do something even more hurtful to devoted owners – ignore them altogether? We want to know why people give in and serve more food when confronted with those big blue or orange eyes, looking sad and needy, says the behavior specialist.
Hungry-looking cats might feel sincerely needy, even when stuffed to the whiskers, Houpt says, because gastric fill is not the only component of satiety. Animals are counting calories, as well as the state of their stomachs, and they find a way to tell us what their bodies are telling them: I want mo-o-o-re!
To participate in the study, which provides medical exams and free food for two months, cats must be at least 25 percent overweight, stay indoors (so they dont supplement their diets with prey), and be within driving distance of the college. If youd like to enroll your cat in the study, or if youd like to chat about your fat cat, you can Email or call 607-253-4350.
Obesity increases a cats risk of other diseases and can shorten its natural life by years, Houpt says. Thats why concerned veterinarians and pet food companies are looking for better ways to answer the cry for Mo-o-o-ore!

Sinus Infections in Cats
Common fungi that float through the air and land on pet food may be responsible for serious sinus infections in cats, researchers at the University of Georgia and Switzerlands University of Zurich report in the Journal of the American Veterinary Medical Association (Vol. 222, No. 10). Diagnosis is difficult and treatment is not always successful, say researchers, who blame Aspergillus and Penicillium for fungal rhinitis and sinusitis in cats.

Cats examined for the study had suffered through months or years of sneezing, foul-smelling nasal discharge and teary eyes. When specialists looked inside the cats heads with CAT scans and rhinoscopy, they found a mess: Whole sections of turbinate bone were eaten away, possibly by the oxalic acid that some fungi produce. Other parts of nasal cavities were clogged by the growth of new tissue that was nearly as dense as tooth enamel.

Delicate surgery removed growths from the sinus cavities, and prolonged drug therapy killed most of the fungus. Researchers were left wondering why common fungi that can afflict other parts of cats – including the respiratory and gastrointestinal tracts – dont cause even more harm in the sinuses. Aspergillus, in particular, is constantly being inhaled and it can readily be isolated, even from commercial dry pet foods, they reported. Most cats mount an immune response and shrug off the fungus.
But the lack of antibodies to massive fungal infections in some cats might offer a clue. Previous infection by feline rhinotracheitis virus or feline calicivirus may have changed mucosal health and local defense mechanisms, they speculated.