Breeding performance of Wistar rats bred in two systems at the conventional Animal House of the Faculdade de Medicina-USP

Abstract

The monogamous system employed in the Wistar rats colony bred at the Central Animal House CDTAEP) of the Faculdade de Medicina-USP showed insufficient for supplying the number of male rats required by the researchers. Aiming at the increase of production and to avoid females wastage, the harem cross-fostered system was introduced into the colony. In this study the  reproductive performance of the animals bred in each system was analyzed during a 17-month period. The results obtained indicated that the monogamous system had the best productivity and provided the young breeders for colony propagation. On the other hand, the harem system could be manipulated for male rats production. It was concluded that the simultaneous maintenance of the two breeding systems was convenient for supplying both laboratories and colony reposition requirements.