the tropics to Alaska. Reasonable ventilation at all temperatures is profitable. By weaning, hamsters are ready for most exposures encountered in shipment anywhere in this country.
30. Culling
Culling reduces litter count and thus affords better milk supply for kittens to be nursed to weaning; therefore, their more favorable development.
Different production purposes direct the litter culling process. Four classes of weaned litters may be listed: 1—Maximum without runts (10 to 16) for pets, etc., regardless of weight standards. 2—Maximum number of a specified weight with uniformity (4 to 14). 3—Maximum weight per kitten, regardless of number, to be weaned at approximately 33 weeks. 4—Sex ratio, or sex controlled weanings, which may be combined with either 1, 2 or 3. Both standard and substandard nest culls removed to control either sex ratio or number weaned may be preserved for fish bait as per Chap. 37.
Again, do not handle pre-sight young in presence of the mother. Remove her from the pen if you wish to inspect the nest of young. Disturb the nest as little as possible then place her back in the pen with a fresh supply of food to occupy her mind in the storing of same. Schools, laboratories, or others inspecting the same nests repeatedly, may omit some regular feedings or great surplus food stores may accumulate. Be careful not to disturb the structure of the nest while removing any such excess stored food. Do not remove her from pen more often than necessary; but, when you do, it may be well to place her in an empty pen, pall or tub with food or nesting materials therein with which she may fill her cheek pouches to shorten her nervous period away from her young. Remember, there is risk each time you so inspect her nest of young unless you have acquired skill in it and extended knowledge of her emotional nature. First sex ratio and runt cullings may be done from 3rd to 5th litter days by the experienced; from 5th to 7th days by the novice. The foregoing suggestions are merely words of caution and guidance given technicians for working purposes and to novices who feel led to early satisfaction of their curiosity as to the nature of the newly born and unweaned hamsters.
Rear doors, as in author’s preference pens, offer decided advantages during nest inspection. They permit careful examination of litter with no disturbance to the nest. Each time one uses them, the rear inspection doors are worth the time required for their construction.
Avoid adding foreign odors, such as tobacco smoke, etc., to either nest or young. Kittens may be lifted out into a small basin lined with clean cloth or paper. Sexes may be separated on basis of Illus. 53. If unable to distinguish sex as early as first inspection, return all except notable runts to the nest, then replace mother to her own pen, and wait until female mammae (nipple) lines are visible with great definiteness. When culling for sex, select the best, largest kittens in the sex ratio desired to be returned to the next. Culled young not saved for baits may be fed to any flesh-eating creature, other than hamster, that may be in need of fresh meat. A light tap on the skull instantly dispatches kittens, as in the case of any other tiny
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