Vol. 275, Issue 6, R2012-R2022, December 1998
Photoperiodic responses of four wild-trapped desert rodent
species
Hanan A.
El-Bakry1,2,
Wafaa M.
Zahran1, and
Timothy J.
Bartness2,3
1 Department of Zoology, Minia
University, 61111 Minia, Egypt, and Departments of
2 Biology and
3 Psychology, Georgia State
University, Atlanta, Georgia 30303
The purpose of this study was to examine
the effect of the photoperiod on reproductive status and body and lipid
masses in four Egyptian desert rodent species
(Dipodillus dasyurus,
Acomys cahirinus,
Gerbillus andersoni, and
Gerbillus pyramidum). Adult males
and females were housed in long days for 11 wk. At that time, one-half
of the animals were killed and the remaining animals were moved to
short days (SDs) for 11 wk. Some individuals of Gerbillus andersoni and
Gerbillus pyramidum had access to
running wheels. Testes index and spermatogenesis, but not testis mass, were decreased in all species in SDs. In contrast, SDs did not affect
female reproductive status in all species. Exercise stimulated spermatogenesis but did not affect female reproductive status. SDs
increased body and lipid masses in male
Acomys
cahirinus, but not in other species.
Collectively, these desert rodent species were responsive to day length
changes, but these changes alone did not induce robust alterations in
reproductive status and body and lipid masses.
white adipose tissue; gerbils; mice; reproduction; body weight; exercise
