Agouti locus may influence reproduction under food deprivation in the water vole (Arvicola terrestris).
The effect of 16-hr food deprivation on day 3 and again on day 5 of pregnancy on the fecundity of female water voles homozygous (ae/ae) or heterozygous (A/ae) for, an allele at the Agouti (A) locus, non agouti extreme (ae) was studied. 63 A/ae females (mated to ae/ae males) produced 115 food-deprived and 115 control pregnancies, and 52 ae/ae females (mated to A/ae males) produced 55 food-deprived and 57 control pregnancies. Regardless of the experimental group, pregnant ae/ae females weighed less than A/ae females. The effect of food deprivation on fecundity depended on the Agouti-locus genotype of the female. In food-deprived A/ae females, fecundity was diminished due to fewer successful pregnancies (P < 0.001) and lower survival of the young (P < 0.05). In food-deprived ae/ae females, reproductive performance was not changed; a somewhat reduced rate of successful pregnancies was compensated for by significantly increased (P < 0.002) postnatal survival of the young. In progeny weaned from food-deprived mothers, the frequency of A/ae females was diminished. Resistance of ae/ae females to the negative effect of nutritional stress, and predominance of ae/ae young in progeny produced by food-deprived mothers, may favour the maintenance of polymorphism for the Agouti-locus in natural populations of the water vole.
Bazhan
N M
NM
Institute of Cytology and Genetics, Novosibirsk, Russia. bazhan@bionet.nsc.ru
Yakovleva
T V
TV
Makarova
E N
EN
D000483:Alleles; D000818:Animals; D003411:Arvicolinae / Q000235:genetics* / Q000502:physiology; D005260:Female; D005298:Fertility / Q000235:genetics* / Q000502:physiology; D005508:Food Deprivation; D009752:Nutritional Status; D010858:Pigmentation / Q000235:genetics*; D011110:Polymorphism, Genetic; D011247:Pregnancy