Evaluation of the Inhalation Toxicology Research Institute beagle dog closed breeding colony: a progress report

Since early 1968, a closed breeding colony has been in operation at the Inhalation Toxicology Research Institute to produce experimental dogs for inhalation toxicology studies and to replace colony breeding stock for producing dogs with a stable gene pool. From March 1, 1968 through July 15, 1974, 123 bitches were bred 613 times, resulting in 540 litters and 2809 puppies: a conception rate for this period of 88.9 percent. An average of 3.74 pups survived to one year of age. (U.S.)