Objective—To determine whether a program of
human interaction or alterations in diet composition
would alter activity of the hypothalamic-pituitaryadrenal
(HPA) axis in dogs housed in an animal shelter.
Procedure—Dogs were (n = 20) or were not (20)
enrolled in a program of regular supplemental human
interaction (20 min/d, 5 d/wk, for 8 weeks) involving
stroking, massaging, and behavioral training. In addition,
half the dogs in each group were fed a typical
maintenance-type diet, and the other half were fed a
premium diet. Plasma cortisol and ACTH concentrations
were measured during weeks 0, 2, 4, and 8 and
before and after exposure to a battery of novel situations
during weeks 0 and 8.
Results—Plasma cortisol concentration was significantly
decreased by week 2, but plasma ACTH concentration
was not significantly decreased until week
8 and then only in dogs fed the premium diet.
Following exposure to novel situations, plasma cortisol
and ACTH concentrations were significantly
increased. However, during week 8, dogs enrolled in
the program of human interaction had significantly
lower increases in cortisol concentration than did
dogs not enrolled in the program.
Conclusions and Clinical Relevance—Results suggest
that both a program of human interaction and
alterations in diet composition have moderating
effects on activity of the HPA axis in dogs housed in
an animal shelter and that activity of the HPA axis
may be increased for a longer period during shelter
housing than measurement of plasma cortisol concentration
alone would suggest. (J Am Vet Med