Breeding Status of the Outbred Wistar Rat Colony in the Strict Hygienic Conventional Facility

breeders (10 weeks old) which divided into 7 mating sets. Each set was matched with the same male breeders (n = 16) to breed four litters during the course of approximately 30 weeks. The breeding performance index parameters obtained in this study, including rates of fertility, weaning, production and litter size were constant at the average values respectively of 93 + 2 %, 99 + 1 %, 92 + 1 % and 11 + 1. The growth rates of the rats produced in these generation numbers indicated normal development. Thus, when taken together with the previously reported microbiological status, data from this study suggested that the Centre had the capacity to breed good quality outbred Wistar rats to meet the usage volume, which currently at > 300 rats per week, within the country.