抄録
This study was initiated in 1968 with the establishment of a colony of Japanese domestic cat free from intestinal parasites at National Institute of Health of Japan. The purpose of the colony was the production of cats of known genetic background and health status for use in biomedical research. This paper describes the performance of the colony over a 5-year period of continuous breeding. 18 females breeders were divided into three groups according to the time of introduction into colony : 5 females initially were introduced in colony ; 7 females were born in 1973; 6 females were born in 1974. Various aspects of reproductive performance in the cat breeding colony were statistically analysed. Data on reproductive performance was as follows : mean age at 1st parturition was 12 months old ; average interval between parturition was 6 months ; mean litter size was 3.5-4.5 born ; percent weaned was estimated 80 to 90 percent. Difference among queens' groups in the colony has not been found except in mean age at 1st parturition. Influence of queens on mean litter size and percent weaned revealed a significant difference. Influence of litter on percent weaned revealed also a significant difference. Litter size and sex effect on percent weaned revealed non-significant difference. It is possible to conclude that aspects of reproductive performance in our colony was similar to the data reported by other investigators referred to this paper. We hope to set up following aspects of reproductive performance as a goal in 1980: mean age at 1st parturition=10.8 months old ; average interval between parturition=4.8 months ; mean litter size=4.5 ; percent weaned=90 percent.
