Analysis of Selection and Management Methods for Breeding Wild Boars

Estrus and Mating in Wild Boars

The wild boar has coarse and sparse hair, generally gray or grayish-yellow. Adult sows weigh 90 kg to 130 kg and are highly responsive to the external environment. Female wild boars generally have 6 to 7 pairs of teats, produce 2.5 litters per year, and generally have 10 to 15 piglets per litter. The suitable mating time is at 5 to 6 months of age, at a body weight of 40 kg to 60 kg. When female wild boars are in estrus, the principle generally adopted is to mate first-litter sows early and multiparous sows late. When a wild boar is in estrus, the external genitalia become noticeably red and swollen; when the external genitalia change from red to dark purple, from swollen to slightly wrinkled, or when the sow stands still while a hand presses down on her rump, this is the best time for mating. Mating between male and female wild boars takes slightly longer than in domestic pigs. Based on experience, it is best to use a repeat-mating method, that is, to mate again after an interval of 6 hours to 8 hours. This can significantly increase the conception rate of the sow. When the female wild boar is in estrus and mating, the method of driving the boar into the sow's pen for 1 day to 2 days can also be used; at this time, the male wild boar can mount and mate multiple times at night. After successful mating is confirmed, drive the male wild boar out. After 20 days, observe again whether the female wild boar is still in estrus; the estrus cycle of female wild boars is generally 18 days. If she is not in estrus, it proves that the wild boar has mated successfully.

Selection of Breeding Pigs

Farms and households engaged in wild boar breeding must have 1 to 2 purebred wild boars. As the saying goes: a good sow benefits one litter; a good boar benefits a whole slope. This shows the importance of the breeding boar. Selecting a good breeding wild boar is of vital importance to the quality of the offspring. Generally, purebred wild boars that conform to wild boar characteristics, such as a long body, long legs, and a pointed snout, are selected as breeding pigs. If the offspring produced by special wild boars crossbred from wild boars and domestic pigs are kept for breeding, the offspring bred from them will show atavism, that is, some of the produced pigs will look partly like domestic pigs rather than wild boars. Therefore, two-way crossbred special wild boars should not be kept for breeding. If conditions are limited and special wild boars must be used as breeding boars, then three-way crossbred special wild boars with more than 70% wild boar bloodline should be selected as breeding pigs, and inbreeding must also be prevented in terms of blood relationship; in this way, their offspring will have strong disease resistance and grow rapidly.

Overfat Breeding Pigs

The wild boar was originally a wild animal and mainly fed on leaves and wild grass, and it retains this characteristic under artificial rearing; 60% to 70% of the feed should be green fodder such as green grass and green vegetables. However, some farmers use their experience in raising domestic pigs and feed wild boars with complete-formula feed, which not only greatly increases costs, but also, because the early growth of reserve breeding pigs is not restricted and the nutrient level in the diet is too high, causes male wild boars to become overfat and too heavy, making it difficult for the boar to mount or making the sow unable to bear the boar's mounting, resulting in mating difficulties or failure to mate normally. At this time, the male wild boar should be subjected to restricted feeding, with green fodder as the main food, while exercise should be strengthened.

Insufficient Nutrition

Breeding boars need relatively large amounts of crude protein and vitamins. If these are insufficient in the diet, it will affect the physique of the breeding boar and the quality of the semen, causing the semen to be scanty and thin, sperm development to be incomplete and vitality to be poor, the conception rate to decline, and even the loss of mating ability. If minerals such as calcium, manganese, zinc, and selenium are lacking, it will also cause gonadal degeneration and sluggish libido. Therefore, the nutrients required by breeding boars should be supplied in a balanced manner. Animal-based feed rich in crude protein, such as fish meal, bone meal, soybean meal, small shrimp, and silkworm pupae, should be supplied year-round, and green, juicy feed rich in vitamins should also be fed more. In northern winters, when green and juicy feed is insufficient, or after male wild boars have mated, vitamin additives can be supplemented. If minerals are lacking, various green and juicy feeds and dried grass meal rich in calcium can be fed more during routine rearing, along with bran rich in phosphorus and an appropriate amount of bone meal, stone meal, or shell meal as supplements.