what variable: Cuvier says, "quatre mois;" others give it as three months, three weeks, and three days; that is. 108 days. According to Mr. Tossier, out of fifteen sows, one littered in 109 days, and one in 123 days, the latitude being fourteen days; according to others, the range of gestation extends from seventeen weeks, or 119 days, to twenty weeks, or 140 days. According to Desmarest, the wild sow goes with young four months and a few days, and produces from three to nine at a birth, suckling them from three to four months. It would appear, then, from these observations, that the period of gestation in the domestic sow varies according to age, constitution, food, and the peculiarities or idiosyncrasies of the peculiar breed. Young and weakly sows not only produce fewer pigs, but farrow earlier than those of more mature age and sounder constitution; and moreover, as might be expected, their offspring are deficient in vigor, often indeed puny and feeble. Here, having trenched upon the subject, we may advert to the principles upon which the breeding of swine should be conducted. Two great objects are in view, fertility and early fattening. With respect to fertility, we rather advocate moderation than excess, both on account of the strength and health of the mother, and the improvement of her progeny from a full supply of nutriment. How long a sow should be kept for breeding depends on circumstances; generally speaking, however, after three or four years the most fruitful sows, exhausted in their reproductive energies, evince a great falling off both in the number and vigor of their young. There are, however, exceptions, … Generally speaking, it is most advantageous to allow the sow to breed only two or three years, and her successors being ready, to fatten her off for the knife.
"A leading principle in breeding this animal,—and it applies equally to the horse, the sheep, the ox, the dog,—is to make a cautious selection of the male by whom the female is destined to conceive her first progeny, for that male stamps a character upon every subsequent produce (whether for good or bad) by other males; 'the subsequent progeny of the mother will always partake more or less of the character of the father of the first offspring.' This law is mysterious, but it has been abundantly proved (See Giles, in Philosophical Transactions for 1821,) and need not be here further insisted on; the fact is established. The selection of the male, then, is of primary importance; of whatever breed he may be, he should be as perfect as possible in the good qualities of his race; he should be free from all blemishes, and be, moreover, the offspring of parents in all points unexceptionable. A young boar intended for breeding from, should be kept separate from the sows until about a year old, when his physical energies will be fairly developed. Form is of more importance than size; in this latter respect the breeds differ, as they do also in the size of the ears, which in some breeds are
