The Research and Consulting Company Ltd (RCC) received 156 breeding pairs of the Wistar Hannover GALAS™ outbred model from Dr. Willy Heine of Zentralinstitut für Versuchstierzucht in Hannover Germany in 1989. The rats were derived by caesarean in 1989. Taconic received breeding stock from RCC in 1998. The rats were refreshed with cryopreserved embryos in 1998. Each member of GALAS received 50 breeding stock from RCC in 1998. The rats were derived by caesarean in 1999. Taconic replaced its previous Wistar Hannover stock with Wistar Hannover GALAS™ in June 2000.