![]() Collin Schaumburg |
![]() Kyle Humphrey |
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![]() Holly Strong |
![]() Natalie Sutton |
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COLLIN
SCHAUMBURG,
KYLE
HUMPHREY, HOLLY
STRONG, NATALIE
SUTTON
Department
of Biology Mentor:
Terry
Derting Title of Presentation:
Effects of Dietary Fiber and Protein on Immunocompetence in White-footed
Mice (Peromyscus leucopus) ABSTRACT Diet quality
is known to have an effect on immune responsiveness. To determine what
aspects of diet affect immunity and what aspects of the immune system
are most vulnerable, we tested the null hypothesis that diet quality has
no effect on immunocompetence and stress levels in the adult male white-footed
mouse (Peromyscus leucopus). Adult males were trapped live from random
patches of forest in western Kentucky. The mice were put on four diets
of differing levels of protein and fiber. Health was assessed through
measurement of daily metabolic rate, white blood cell counts, hematocrit,
serum corticosterone level, and body organ masses. Differences in the
four diets were confirmed by differences in the masses of the gastrointestinal
organs, kidneys, and liver. Protein was more influential on organ masses
than fiber. Despite differences in digestive efficiencies, final daily
metabolic rates on all four diets were similar, confirming that all mice
used similar amounts of metabolic energy per day. The differences in diet
quality among groups were not associated with differences in immunocompetence.
Our results indicated that differences in diet quality, which mimicked
variation that occurs seasonally in the field, did not have a direct effect
on immunocompetence. We propose that the relationships between diet quality
and immunocompetence which occurred in a previous field study were simply
correlative and not causal. Alternatively, immunocompetence may be more
influenced by environmental stressors that are directly or indirectly
correlated with diet quality such as predation, parasitism, or habitat
quality, than by dietary factors alone. Date Modified December, 2004
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