What are the excellent breeding pigs introduced from abroad in our country?

   there are five famous pig breeds in the world, namely, Yorkshire, Landrace, Duroc, Hampshire and Pittland, which are famous for their fast growth rate, high feed conversion rate, high carcass lean percentage, wide distribution and large feeding volume.

   (1) Yorkshire Pig

   1, Origin and Distribution: also known as Yorkshire Pig, originated in Yorkshire and its neighboring areas in the north of England.

   2, physique appearance: the back hair is white, the body is large and round, is rectangular, the head is long, the face is wide and moderately sunken, the ears are upright, the mouth is straight and slightly arched, the limbs are high, and the hindquarters are wide and long. More than 6 pairs of sow nipples.

   3, production performance: Yorkshire pigs have high reproductive performance, with an average of 12.5 sows and 11 live piglets. Sows have strong lactation and high lactation rate. Compared with Chinese local pig breeds, the sexual maturity of sows is later than that of Chinese local pig breeds. Zuoke sows at the proestrus of 5 months have the advantages of faster weight gain, higher feed conversion rate, higher carcass lean percentage, higher litter size and good lactation performance of sows.

   4, crossbreeding utilization: the common crossbreeding method for Yorkshire pigs is: Duroc long x or Duroc big x long, that is, Landrace boars (sows) are mated with Yorkshire sows (boars) to produce commercial pigs, and hybrid first generation sows are crossbred with Duroc boars (terminal male parents) to produce commercial pigs. This is a good combination at present. In China, Yorkshire pigs are used as male parents to carry out binary or ternary crossbreeding with local pigs, and the effect is also very good.

   (II) Landrace Pig

   1, Origin and Distribution: formerly known as Landrace Pig, originated in Denmark.

   2, physique appearance: the whole body is white hair, the body is streamlined, the head is small, the nose and mouth is straight, narrow and long, the ears are parallel and straight forward, the waist is long, the hindquarters are well developed, and the buttocks and legs are plump. 7-8 pairs of nipples, more than 6 pairs of effective nipples

   3, production performance: Landrace pig has the excellent characteristics of fast growth rate, high feed utilization rate, high lean percentage and high litter yield, but poor stress resistance, weak hindlimb, high requirement for feed nutrition and late sexual maturity.

   4. Cross utilization: Landrace pigs are often used as female parents in production. It has the characteristics of fast weight gain, high feed conversion rate, thin fat and more lean meat, and the lean meat rate can reach 62%. If Landrace pigs were used as male parents and local improved pigs as female parents, the litter size, daily gain, lean percentage and feed conversion rate could be significantly increased.

   (3) Duroc Pig

   1, Origin and Distribution: originated in New Jersey and New York in the eastern United States.

   2, physique and appearance: the original Duroc pig has reddish brown fur, symmetrical and compact structure, stout limbs, deep body, well-developed muscles, moderate head size, handsome head, slightly concave face, short straight mouth, moderate ear shape or drooping forward.

   3, production performance: it has the advantages of fast weight gain, high feed reward, good carcass quality, large eye muscle area and high lean percentage, but the average litter size of Duroc sows is about 9, the motherhood is poor and the breeding rate is low.

   4, crossbred Lichuan: Duroc pigs have good production performance, but because of their poor reproductive performance, they are often used as male parents when crossing with other pig breeds in order to increase lean meat and litter size.

   (4) Pitland Pig

   1, Origin and Distribution: originated in Brabant province of Belgium, it was bred by backcrossing between French Bei Ye crossbred pig and British Buckshire pig, and then crossbred with British large White pig.

   2, physique and appearance: the coat is grayish white with irregular dark black spots and occasionally a few brown hairs. The head is handsome, the face is straight, the mouth is large and straight, and the ears are slightly forward; the body is cylindrical, the abdomen is parallel to the back, the shoulders are full, and the back is straight and broad.

   3, production performance: rapid growth, 6-month-old body weight can reach 90,100kg, daily gain of about 750g, per kilogram weight gain consumption of compound feed 2. 5kg. 2.6kg, slaughtering rate up to 76%, lean meat percentage can be as high as 70%.

   3, cross utilization: because of the high meat production performance of Petrand pigs, they are often used as male parents for binary or ternary hybridization. Some domestic breeding farms often cross with Duroc pigs to produce Pi x du dual hybrid boars, with a lean meat rate of 72%, which is a good terminal male parent.

   (5) Hampshire Pig

   1, Origin and Distribution: originated in Buoni, Kentucky, USA.

   2, physique and appearance: black pig body, white forelegs, black hind legs. There is a white belt around the shoulder and neck, including the shoulder blades, forechest and forelimbs, showing a white belt ring. In the white and color and black edges, a gray belt is formed by black skin and white hair, so it is also called silver belt pig. The head is medium-sized, the ears are medium-sized and upright, the mouth is long and straight, the body is long, the waist is arched, and the hindquarters are muscular.

   3, production performance: the sexual maturity of Hampshire pigs is relatively late, the first estrus of sows is generally 5 months old, the litter size is about 10 per litter, the growth rate of Hampshire pigs is slow, the daily increase is about 700g, the feed utilization rate is about 3. 0, the lean rate is 61%, and the slaughter rate is more than 72%.

   4, crossbreeding utilization: in foreign countries, hybrid boars are produced by crossing Hampshire pigs with Duroc pigs as male parents, and Yorkshire pigs and Landrace pigs as female parents. Two-hybrid sows can significantly improve the production performance of commercial pigs.