Neijiang pig belongs to the southwest type of pig breed. Originating in the Neijiang region of Sichuan Province, distributed in the middle reaches of the Yangtze River Basin, the central production area around Dongxing Town in Neijiang City, historically known as "Dongxiang Pig".
The neijiang pig is covered in black hair, has a large body, a wide and deep body, and a particularly developed forehustem. The head is short, wide and wrinkled, the ears are large and droopy, the neck is medium long, the chest is wide and deep, the back and waist are wide, the abdomen is large and droopy, the hips are wide and flat, and the limbs are solid. Neijiang pigs can be divided into early maturing breeds, medium maturing breeds and
Late maturing seeds. Early maturing breeds can weigh up to 125 kg in 12 months, medium maturing breeds can weigh 150 to 180 kg in 12 months, and late maturing breeds can weigh up to 250 kg in 2 years.
Sows are more fertile, giving birth to 10 to 20 litters per litter. The newborn weighs 0.78 kg, the 2-month-old weaning weighs 13 kg, and the fattening pig can weigh up to 90 kg at 7 months old, and the slaughter rate is about 68%. Adult boars weigh about 168 kg and sows about 154 kg. To the heat, cold
Cold and plateau areas above 4000 meters above sea level can adapt. With this pig as the father and other local pigs hybridized, the daily weight gain of hybrid offspring increased by 15% to 20%. With duroc pigs as the father and this pig hybrid, the carcass lean rate of the hybrid offspring increases, the skin becomes thinner, and the daily weight gain is also significantly increased.
Neijiang pigs have the characteristics of strong adaptability and good hybrid coordination, and are one of the good parents for the utilization of pig hybrid advantages in North China, Northeast China, Northwest China and Southwest China, but there are shortcomings such as low slaughter rate and thick skin.
Cooperative pigs, also known as fern pigs or mountain pigs, are high-prototype pig breeds. It is native to parts of Xiahe, Luqu, Lintan, Zhuoni, Diebu and other counties in Gannan Tibetan Autonomous Prefecture, Gansu Province.
Cooperative pigs are small, wild, lively and clever. There are fewer pure black coats, generally the limbs, abdomen, and back are mostly white, the coat is thick and long, the winter brown fluff, and the mane is long and tough.
The back of the newborn piglet has brownish yellow longitudinal stripes on its back, which gradually disappear with age. The head is narrow and long, tapered, the head length is 31.26% of the body length, the mouth is long and pointed, the canine teeth are developed, the lower canine teeth are more than 20 cm long, the ears are small and upright, and there are no obvious wrinkles on the forehead. The neck and body are shorter and narrower, the back and waist are straight or slightly arched, the posterior body is slightly higher than the front body, and the hips are narrow and oblique. The limbs are moderate in length, robust, with small and firm hooves, and 4 to 6 pairs of nipples, neatly arranged.
Cooperative pigs are a small, slower-growing pig breed that is suitable for grazing. Adult boars weigh 33.31 kg and sows 34.84 kg. Sows begin to breed at 4 to 5 months of age, use 5 to 6 years, up to 8 to 10 years, the number of litters is small (average 3.6 heads), and the reproduction rate is low. Piglets are castrated and fattened after weaning, and the fattening period is slow, and the piglets born in February to March of that year weigh 20 to 25 kg by the end of the year.
If the concentrate is fed two months before slaughter, the live weight can reach 50 kg, the slaughter rate is 69.57%, and each pig produces 2.33 kg of plate oil. Lean meat, thin skin tender, slightly sticky, suitable for making bacon, delicious taste. "Roast piglets" made from piglets are one of the famous dishes in the northwest. The mane is long and tough, the mane is 12 to 18 cm long, and each pig produces 93 to 186 grams of mane, up to 250 grams. This species can grow and reproduce normally in the alpine and humid semi-agricultural and semi-pastoral areas at an altitude of 3000 meters and the lowest temperature of -28.5 °C. Grazing performance is very strong, with rapid running, not easy to fatigue, can defend against predators, not afraid of exposure and wind and snow, and jumping over the cliff and other special properties, especially suitable for extensive management of grazing conditions
feeding.
Since the end of the 19th century, there have been more than ten pig breeds introduced from abroad, among which the greater impact on the improvement of pig breeds in China is the Middle Yorkshire Pig, the Baksha Pig, the Yorkshire Pig, the Su White Pig, the Kemilov Pig, the Changbai Pig, etc. In the 1980s, The Dugueck, Hampshire and Pitland pigs were introduced. At present, the lean pig breeds that have a greater impact in China are The Yorkshire pig, the long white pig, the Duroc pig, the Hampshire pig and the Pitland pig.
The introduction of pig breeds has the following common characteristics:
(1) Fast growth rate and high feed remuneration
The foreign pig breeds introduced have large physiques, well-proportioned bodies, slightly arched backs and waists, and higher limbs. Under good feeding management conditions, the reserve pigs grow and develop rapidly. The daily weight gain during the growth and fattening period is 550 to 700 grams, which shows the characteristics of high feed remuneration.
(2) The slaughter rate and carcass lean meat rate are high
The slaughter rate of introduced pig breeds is relatively high, and the slaughter rate is 70% to 72% when weighing about 90 kg. The dorsal body is thin, the eye muscle area is large, and the carcass lean meat rate is high. Carcass lean meat rate of 90 kg is 55% to 62%, or even higher. Therefore, the introduction of pig breeds is generally used as the father of breeding pigs.
(3) Low reproduction rate
Compared with domestic local pig breeds, the number of piglets produced by introduced pig breeds is generally small, and the sows are not obvious in heat and are difficult to breed.
(4) Poor meat quality
The edible quality of the meat introduced into pig breeds is inferior to that of local pig breeds in China, mainly manifested by the large diameter of muscle fibers and poor taste; The meat color and texture of the introduced pig breeds are not as good as those of local pigs in China, and the main manifestations are that the meat color is lighter, the fat content in the muscle is low, and the marbling is not rich and uniform;
Introduced pig breeds have a higher proportion of pse meat (white muscle) or dfd meat (black dried meat), especially Pitland pigs, whose incidence of pse meat is higher; Although the incidence of pse meat is low, the duroc pig, the great white pig and other varieties is lower, but its meat color is not as good as that in China
Pig breeds.
(5) Poor stress resistance and higher requirements for feeding management conditions
Introduced breeds require more pig concentrate, and at lower nutrient levels, growth and development are slow, sometimes inferior to local pig breeds in China.
(i) Yorkshire pigs
The Yorkshire pig is native to the United Kingdom and is found all over the world. China has been introduced for many years, because of its large size, coated with all white, also known as the great white pig. Yorkshire pigs have the characteristics of many litters, fast growth rate, high feed utilization rate, high carcass lean meat rate, bright red meat color and strong adaptability.
Yorkshire pigs are tall, with a long head and neck, a wide and slightly concave face, and upright ears; The body is long, the back and waist are straight or slightly arched, the abdominal line is flat, the chest is wide and deep, the posterior body is wide and long, and the effective nipples are more than 6 pairs. The primary piglets produced 9.5 to 10.5 heads, the piglets produced 11 to 12.5 heads, the fattening pigs weighed 100 to 110 kg at the age of 160 to 175 days, the feed conversion rate was 2.7 to 2.9, the carcass lean meat rate was 63% to 65%, and the thickness of the dorsal fat when weighing 100 kg was about 10 mm.
Yorkshire pigs are mostly used as the first parent or basic mother in hybridization, which is highly valued by the majority of farm households. Its social inventory is large, its resources are abundant, its distribution is relatively widespread, and its utilization is relatively sufficient. China already has its own selection of "Chinese Great White Pigs".
(2) Long white pig
The long white pig, also known as the Landres pig, is native to Denmark and is distributed all over the world, and is the world's most famous lean pig breed. China has been introduced for many years, because of its long body, the coat color is all white, known as the long white pig.
The long white pig has the characteristics of many litters, fast growth rate, high feed utilization rate and high carcass lean meat rate, but its stress resistance is poor, and the feed nutrition requirements are high. The head of the long white pig is small and beautiful, the face is straight, and the ears are lightly forward; The body is long, narrow in front and wide in a streamlined shape, the back and waist are slightly arched, the abdomen is straight, the hips are plump, muscular, the physique is firm, and the effective nipples are more than 6 pairs.
The primary sows produce 9 to 10 litters, and the sows produce 11 to 12 litters; Fattening pigs weigh 100 to 110 kg at 65 to 180 days old, have a feed conversion rate of 2.85 to 2.95, a carcass lean meat rate of 65% to 66%, and a dorsal fat weighing 100 kg
The thickness is about 9.7 mm.
China's introduction of Changbai pig has a long history, is an indispensable pig breed in the production of commercial pigs or breeding new breeds (lines) hybridization support, hybridization is mostly used as the first father. China already has its own selective breeding of "Chinese Long White Pig".
(iii) Duroc pigs
Native to the United States, the Duroc pig is a world-famous fresh meat breed that is distributed all over the world. Our country has been introduced for many years. Duroc pigs have many advantages such as fast growth rate, high feed utilization rate, high carcass lean meat rate, good carcass quality, and strong adaptability.
Duroc's fur is brownish red, a few are light brown to dark brown, the head is small, the face is slightly concave, the ears are medium in size, and the tips of the ears are hunched forward; The body is wide and deep, the back is arched, the limbs are thick, the hoof shell is black, the legs and hips are muscular, and the effective nipples are more than 6 pairs;
The primary piglets produce 8 to 9 litters, and the piglets are produced 10 to 11. Fattening pigs weigh 100 to 110 kg at 165 to 175 days old, have a feed conversion rate of 2.8 to 2.95, a carcass lean meat rate of 65% to 67%, and a dorsal fat thickness of about 10 mm with a body weight of 100 kg.
Duroc pigs are suitable as parents in binary or ternary hybridization. China also has its own selective breeding of "Chinese Duroc pigs".
Hampshire pigs are native to the Buoni region of Kentucky, USA, and are selected from the cross-breeding of thin-skinned pigs with medium-banded pigs.
The pig has a black coat, a white band at the junction of the shoulders and neck, and a white shoulder and forelimbs (also known as a silver belt pig). The ears are medium large and erect, the body is long, the muscles are developed, the limbs are solid, the growth is fast, the feed utilization rate is high, the carcass quality is good, and the lean meat rate is more than 60%.
Adult boars weigh 315 to 410 kg and sows 250 to 340 kg. In general, the number of litters is about 10, and the live weight of fattening pigs at 6 months old can reach 90 kg.
In 1934, China introduced a small amount for the first time, and after 1978, hundreds of heads were successively introduced from Hungary and the United States. Due to the characteristics of Hampshire pigs with lean meat and thin back, with Hampshire pigs as the father, local breeds of pigs can significantly improve the lean meat rate of commercial pigs after hybridization.
The Pitland pig is native to Belgium. Pitland pigs have a white complexion with black to maroon spots, upright ears, short bodies, wide ears, and particularly developed posterior muscles. Its lean meat rate is particularly high, the dorsal fat is very thin, the feed utilization rate is high, but the daily weight gain, reproductive performance is low, and the meat is inferior
(PSE meat) has a high incidence and is highly stress sensitive.
Due to the particularly high lean meat rate, pitland pigs are mainly used in foreign countries for commercial pig production, as a parent and anti-stress breed hybrid, the production of commercial pigs. The lean meat rate of the carcass is as high as 66% to 70%, which is the highest lean meat rate in the world. However, this variety has a strong stress response, coarse muscle fibers, poor flesh quality, and slow growth, especially in the late growth period, and the growth rate is significantly slowed down.