Statistical considerations concerning the disposal of dairy bulls used for artificial insemination in Hokkaido from 1958 to 1979.
D000367:Age Factors; D000818:Animals; D002417:Cattle / Q000502:physiology*; D005298:Fertility; D007315:Insemination, Artificial / Q000662:veterinary*; D007564:Japan; D008017:Life Expectancy; D008297:Male; D012662:Semen Preservation / Q000662:veterinary