What are the excellent breeding pig breeds introduced into China from abroad?

  There are five famous pig breeds in the world today, namely the Large Yorkshire pig, the Landrace pig, the Duroc pig, the Hampshire pig, and the Pietrain pig, which are known for their fast growth rate, high feed conversion rate, high carcass lean meat rate, wide distribution, and large rearing numbers.

  (I) Large Yorkshire pig

  1. Origin and distribution: Also known as the Yorkshire pig, it originated in Yorkshire in northern England and its neighboring areas.

  2. Constitution and appearance: The whole body has white bristles, the body is large and round, rectangular in shape, with a long head, a broad face with a medium depression, erect ears, a straight mouth that is slightly arched, relatively high legs, and a broad and long hindquarter. Sows have more than 6 pairs of teats.

  3. Production performance: The Large Yorkshire pig has relatively high reproductive performance. Multiparous sows average 12.5 piglets born per litter and 11 live piglets born. Sows have relatively strong lactation and a relatively high nursing rate. Sexual maturity is later than that of Chinese local pig breeds. The first estrus of sows is at about 5 months of age. The Large Yorkshire pig has advantages such as fast weight gain, high feed conversion rate, relatively high carcass lean meat rate, relatively large litter size, and good lactation in sows.

  4. Crossbreeding utilization: The commonly used crossbreeding method for Large Yorkshire pigs is: Duroc x Landrace x Large Yorkshire or Duroc x Large Yorkshire x Landrace, that is, using Landrace boars (sows) to mate with Large Yorkshire sows (boars) for production, and then using Duroc boars (terminal sires) to crossbreed the first-generation crossbred sows to produce commercial pigs. This is currently a relatively good combination. In China, using Large Yorkshire pigs as the sire to carry out two-way crossbreeding or three-way crossbreeding with local pigs also produces very good results.

  (II) Landrace pig

  1. Origin and distribution: Originally named the Landrace pig, it originated in Denmark.

  2. Constitution and appearance: The whole body has white hair, the body is streamlined, the head is small, the snout is straight and narrow and long, the two ears extend straight forward and downward in parallel, the back and loin are very long, the hindquarter is well developed, and the rump and legs are full. There are 7 to 8 pairs of teats, with more than 6 functional teats.

  3. Production performance: The Landrace pig has excellent characteristics such as fast growth rate, high feed utilization rate, high lean meat rate, and large litter size, but it has poor stress resistance, weaker hind legs, higher requirements for feed nutrition, and later sexual maturity.

  4. Crossbreeding utilization: In production, Landrace pigs are mostly used as dams. They have the characteristics of fast weight gain, high feed conversion rate, thin backfat, and more lean meat, and the lean meat rate can reach 62%. If Landrace pigs are used as the sire and excellent local pig breeds in China are used as the dam, the crossbred offspring can significantly improve litter size, daily weight gain, lean meat rate, and feed conversion rate.

  (III) Duroc pig

  1. Origin and distribution: Originated in New Jersey, New York, and other places in the eastern United States.

  2. Constitution and appearance: The original Duroc pig has a brownish-red coat color, a well-proportioned and compact structure, sturdy limbs, a deep and broad body, and well-developed muscles. The head is moderate in size and relatively refined, the face is slightly concave, the snout is short and straight, and the ears are moderate in shape or droop forward.

  3. Production performance: It has advantages such as fast weight gain, high feed return, good carcass quality, large loin eye area, and high lean meat rate, but Duroc sows average about 9 piglets born per litter, have poorer maternal qualities, and a relatively low rearing rate.

  4. Crossbreeding utilization: The Duroc pig has good production performance, but because its reproductive performance is relatively poor, when crossbreeding with other pig breeds it is often used as the sire to achieve the goals of increasing lean meat production and improving litter size.

  (IV) Pietrain pig

  1. Origin and distribution: Originated in Brabant Province, Belgium, and was developed by backcrossing French Bayeux crossbred pigs with British Berkshire pigs, and then crossing them with British Large White pigs.

  2. Constitution and appearance: The coat color is grayish-white with irregular dark black spots, and occasionally a few brown hairs appear. The head is refined, the face is flat and straight, the mouth is large and straight, and the two ears are slightly forward; the body is cylindrical, the abdomen is parallel to the back, the shoulder muscles are full, and the back is straight and broad.

  3. Production performance: It grows rapidly, and body weight can reach 90 to 100 kg at 6 months of age. Daily weight gain is about 750 g, and each kg of weight gain consumes 2.5 to 2.6 kg of compound feed. The dressing percentage reaches 76%, and the lean meat rate can reach as high as 70%.

  3. Crossbreeding utilization: Because the Pietrain pig has high meat production performance, it is mostly used as a sire for two-way or three-way crossbreeding. Some domestic breeding farms often cross it with Duroc pigs to produce Pietrain x Duroc two-way crossbred boars, with a lean meat rate of 72%, making it a good terminal sire.

  (V) Hampshire pig

  1. Origin and distribution: Originated in the Boone County area of Kentucky, United States.

  2. Constitution and appearance: The pig's body is black, the forelimbs are white, and the hindlimbs are black. A white band encircles the junction of the shoulder and neck, including the shoulder blade area, forechest, and forelimbs, forming a white belt ring. At the border between white and black, a gray band is formed by black skin with white hair, so it is also called the silver-belt pig. The head is medium-sized, the ears are medium-sized and erect, the mouth is relatively long and straight, the body is relatively long, the loin is arched, and the hindquarter and rump muscles are well developed.

  3. Production performance: Hampshire pigs mature relatively late sexually. The first estrus of sows is generally at 5 months of age, and litter size is generally about 10 piglets per litter. Hampshire pigs grow relatively slowly, with a daily gain of about 700 g, a feed utilization rate of about 3.0, a lean meat rate of 61%, and a dressing percentage above 72%.

  4. Crossbreeding utilization: Abroad, Hampshire pigs are crossed with Duroc pigs to produce crossbred boars used as sires, and Large Yorkshire pigs are crossed with Landrace pigs to produce crossbred sows used as dams for double crossbreeding, which can significantly improve the production performance of commercial pigs.