young. Thus, no element of cruelty is involved. Culling of litters is practiced in production of finest cat, dog, and other stock, so the custom of culling and dispatch of culls is not new. However, the hamster is a small animal and skill must be exercised in successful culling practices. At birth, litters may contain 4 to 18 kittens during the mother’s best production, female kittens frequently outnumbering males. In unculled, poorly cared for litters, the mother’s pampering of male offspring usually leaves female kittens in the minority. Amateurs who let nature take its course are heard to say that hamster production shows males in the majority. Skill in culling, feeding, and other care reverses the sex ratio in well-managed weanings, and permits the owner to control the pattern for production. The average mother hamster, properly fed, etc., may nurse 6 to 10 weannig kittens of standard weight, readily permitting 30 to 40 kittens per female’s productive life of 5 to 6 litters, and that output without secial or supplemental feedings as hereinafter provided for. Although pet stock need not meet laboratory or breeding stock requirements, for best production, the runts (distinctly undersize kittens) should be removed by the 7th to 9th day and litter count held within reason. For production of best possible young breeders, 4 to 6 young should be the maximum number weaned without supplemental feedings, or 6 to 10 with supplemental feedings, depending upon size, age and quality of the mother.
Special advantages in culling for sex ratio lie in the fact that one may raise the right proportion of females to sell for breeders, or may raise all males if filling laboratory orders specifying same. Cull according to your production purpose, and save yourself from feeding unwanted animals.
For convenience in culling, feeding and other servicing of pens, there are advantages in mating all females to be housed in the same 4-pen unit so as to litter at about the same time.
31. Sex Distinctions
As shown in Illus. 1, the male adult is distinguished by his elongated rear section. The female squares off bluntly at the hips, as shown by the F and arrow pointing to the dash line showing how female hip and read section appear in contrast when placed upon picture of the male for comparison. The male elonga-
tion of the rear develops rapidly from the 15th day until he is approximately 12 weeks of age. The sides of this protruding rear are usually lighter color than
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