The link between stress and disease in cats is well-established, and it’s hard to imagine a more
stressful environment for a cat than an animal shelter. Researchers at the Koret Shelter Medicine Program found that stress-induced loss of appetite and weight may provide an early warning sign
for impending URI in shelter cats.

From Koret:

Did you know cats can lose weight in a shelter environment? Our latest research found
over 80% of healthy cats that entered a shelter lost weight during their shelter stay.
“Associations among weight loss, stress, and upper respiratory tract infection in shelter
cats” was published in JAVMA (Journal of American Veterinary Medical Association) in
March of 2012. This research has helped us quantify some of the changes we see in feline
health as cats go through an animal shelter system. We documented that many shelter
cats do not eat well during their first week in the shelter. In fact, their appetites were
reduced to the point of losing weight. About a quarter of cats lost more than 10% of their
body weight during their shelter stay – much more than we expected.

The research team tracked stress scores and recorded food intake for the first 7 days of
shelter stay and found that stress and food intake were highly correlated: cats that had
high stress scores tended not to eat very well. Many cats had higher stress scores for their
first few days in the shelter, but when stress scores decreased, their food intake rose. This
finding was especially revealing, as it held true across the group of cats that were studied.
Additionally, not only was high stress related to lower food intakes, cats with high stress
scores were at significantly more risk for upper respiratory infection (URI) than cats with
lower stress scores.

Read the full discussion here.