Abstract
The breeding of wild-caught rodent Holochilus brasiliensis (Desmarest, 1819) was studied under laboratory conditions. The mean gestation length was 28-4 days. Litter size ranged from one to five. Males matured at 2-3 months and females at 2-4·5 months of age. The oestrous cycle lasted 6-8 days. Eleven pairs observed over 6-13 months increased to a population of 276 individuals (153 males and 123 females).