Lactational estrus induction in the Mexican hairless sow.

The purpose of this study was to determine the effects on the reproductive performance of the Mexican hairless pig (MHP) while inducing fertile lactational estrus. Lactational estrus was induced on day 8, postpartum, in 20 primiparous sows during two consecutive reproductive cycles. Boar presence and temporary litter withdrawal were used as stimuli.

The menstrual cycle of the spider monkey (Ateles geoffroyi).

The ovarian cycles of four adult female spider monkeys (Ateles geoffroyi) were followed daily throughout 30 days by means of vaginal swabs and blood samplings. Cytological analyses of the vaginal swabs and radioimmunoassay determination of the daily levels of estradiol-17 beta (E2) and progesterone (P4) wer done in order to classify the kind of ovarian cycle of this species. Our results show that Ateles geoffroyi females display menstrual cycles of about 24 days on average.

Self and Social Grooming in Stump-Tailed Macaques: Effects of Kin Presence or Absence within the Group.

The relation between individual self and social-grooming scores, asaessingthe effects of having or lacking relatives within the group, was studied in a colony of stump-tailed macaques (Macacaarctoides). As it has been shown by other authors, kinship favoured grooming interactions, so animals lacking relatives wen seldom mom as groomees. Conversely, these subjects accounted for the major mounts of self-grooming, as if they were surmounting the social grooming deficit.