Increased fertility in young primiparous female bank voles, Clethrionomys glareolus, treated with prolactin or progesterone after mating

Self Cite

Between 30 and 40 days of age, female bank voles were kept singly, in female pairs, separated from an adult male by a wire mesh, or paired with a vasectomized male. At Day 40 they were paired with adult intact males. Fertility at the first mating was low (22-25%), but if the females had previously mated with the vasectomized male fertility of the subsequent mating with the intact male was significantly increased (63%). Sterile matings therefore had a priming effect on the females, and could be important for the development of puberty in wild females. Only 55-59% of the females without contact with males between Days 30 and 40 mated with the fertile male. Contact with a male through a wire mesh increased the proportion to 80% and co-habitation with a vasectomized male to 94%. In the last group, mating also occurred at a younger age.

Section: Day 40 To 60 Of Agementioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Influence of sexual experience and social environment on fertility and incidence of mating in young female bank voles (Clethrionomys glareolus)

Westlin¹,

Gustafsson²

1983

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“…The present results would suggest that one contribution to the rise in fertility might be an increased sensitivity of the endometrium to the presence of blastocysts. However, this does not rule out the possibility that there is a change with age in the luteotrophic response to copulation (Westlin, 1982;Westlin & Gustafsson, 1984), although this has not been investigated experimentally.…”

Section: Discussionmentioning

confidence: 99%

“…It has been suggested that this is due to deficient output of progesterone by the ovaries, attributed to insufficient release of luteotrophin (Westlin, 1982). It has been supposed that either the threshold stimulus arising from mating and required to activate the luteotrophic complex is higher in young females than the satiety point of copulation for males, or that young females do not allow mating to satiety (Westlin & Gustafsson, 1984).…”

Section: Introductionmentioning

confidence: 99%

Hormonal requirements and the influence of age on the decidual cell reaction in the bank vole (Clethrionomys glareolus)

Nerquaye-Tetteh¹,

Clarke²

1987

Summary. Laboratory bred bank voles of different age and reproductive status were bilaterally ovariectomized, treated with exogenous oestrogen or progesterone or both, and given an artificial decidual stimulus (crushing with artery forceps). An hormonal regimen of oestrogen (100 ng) followed by progesterone (1 mg) and small amounts of oestrogen (10 ng) was necessary for maximal development of the decidual cell reaction (DCR). A DCR did not develop if the animals were treated with only oestrogen or progesterone. Middle-aged virgin females 5\p=n-\7months old had larger responses than did young virgin females 2\p=n-\3months old, and parous females, 15\p=n-\19months old and having had at least 10 litters, had a response similar to that of virgin females of about the same age. The size of the DCR in old parous females was inversely related to the time elapsing since the last litter. It is concluded that in its hormonal requirements for a successful DCR the bank vole is similar to the mouse. The results also suggest that the increase in fertility of bank voles up to the age of about 100 days may in part be explained by increased response of the endometrium to blastocysts. The reduction in size of the DCR in old animals is a consequence of ageing rather than of repeated pregnancies.

“…Young female bank voles frequently fail to become pregnant at their first matings. This occurs if the stud male is left with the female (Westlin & Nyholm, 1982) as well as if the stud male is removed and the female kept alone (Westlin, 1982b). Young females may have higher requirements for vaginal stimulation to activate the luteotrophic complex and one explanation for their lower fertility could be that the stimulus threshold for activation is seldom reached.…”

Section: Introductionmentioning

confidence: 99%

Influence of age and artificial vaginal stimulation on fertility in female bank voles (Clethrionomys glareolus)

Westlin¹,

Gustafsson²

1984

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Female bank voles mated when 30-50 days old showed only 20-25% fertility at the first mating, but fertility increased to about 80% in animals greater than 100 days of age at the first mating. Young females subjected to artificial cervical stimulation after the completion of a normal mating showed a much higher fertility than normally mated controls (76 compared with 29%). The reason for the low fertility therefore appears to be that young females require more stimulation to activate the corpora lutea than is normally received at a mating.