Reproduction in the slender loris (Loris tardigradus malabaricus).

A breeding colony of slender lorises (Loris tardigradus malabaricus) was studied to obtain data for comparison with other prosimian species, to contribute reproductive information for improving management of captive lorises, and to resolve some uncertainties in the literature regarding reproduction in the slender loris. At the Duke University Primate Center, a female slender loris reached sexual maturity at approximately ten months of age and conceived at one year of age. The length of the estrous cycle was 29-40 days, with copulation occurring over two consecutive days during estrus. Gestation length was 166-169 days. Litter size for each six births was one. Conception did not occur during an immediate post-partum estrus, but four months after birth, resulting in a 9 1/2-month interbirth interval. There was no evidence of reproductive seasonality. Lactation lasted between five and seven months. Reproductive rates of slender lorises are among the lowest of primates less than 500 g. Differences in reproductive parameters may exist between different subspecies of slender lorises.