What are the breeds of improved pigs? A overview of common excellent pig breeds
What are the breeds of improved pigs? The breeds of improved pigs include the new Chinese lean-type pig line, the Rongchang lean-type pig line, the Jihe White pig, the Landrace, the Hubei White pig, the Zhejiang Middle White pig, the Sanjiang White pig, the Dekalb pig and the Xiangbai pig, among others. A detailed introduction follows.
New Chinese lean-type pig line
The breeding of this line was a major national science and technology project during China's "7th Five-Year Plan" and "8th Five-Year Plan". This line has 4 sire lines and 5 dam lines. For the new sire lines, large-scale successive-generation selection was carried out on introduced pig breeds (Large White, Duroc, Landrace) under China's existing conditions (climate, feeding, management, etc.), taking care to maintain the advantages of these pig breeds in traits such as growth rate and lean meat percentage, while also selecting for limb and hoof soundness, stress resistance and reproductive performance. After selection, the carcass lean meat percentage of the new sire lines increased markedly, from 60.6% to 62.24%; the age at 90 kg body weight was shortened from 175 days after birth to within 160 days; and the feed consumed per kg of weight gain dropped from 3.0 kg to 2.8 kg. The new dam lines mainly make use of the characteristics of China's local improved breeds, such as large litter size and good meat quality. After selection, the 5 new dam lines reached a litter size of 12.5-15.67 piglets, a body weight of 90 kg at 172 days of age, and a carcass lean meat percentage of 54.31%-61.08%. The average lean meat yield per litter of the crossbred combinations reached 475.5 kg, reaching the advanced level of similar research at home and abroad. Breeding pigs have been promoted throughout more than 20 provinces, municipalities and autonomous regions across the country.
Rongchang lean-type pig line
The Rongchang lean-type pig line was a key research project of the Ministry of Agriculture during the "7th Five-Year Plan" and "8th Five-Year Plan". This line was developed on the basis of selection of the original Rongchang pig, with appropriate introduction of Landrace blood, closed herd and successive-generation selection; while maintaining the coat color and excellent meat quality characteristics of the original Rongchang pig, it focuses on raising the lean meat percentage and appropriately improving feed conversion efficiency and growth rate. This line has a completely white coat, with black spots on the head (the coat color characteristic of the original Rongchang pig), a straight snout of medium length, medium-sized ears that droop slightly, a head of moderate size, a straight back and loin, and a full hindquarter. The limbs are fairly long and sturdy, with more than 6 pairs of functional teats. Its reproductive performance is similar to that of the Rongchang pig, with a litter size of 12.74 piglets for sows after multiple parities, a weaning litter weight of 128 kg, an age at 90 kg body weight of 180.7 days, an average daily gain of 0.635 kg during the 20-90 kg stage, a feed-to-meat ratio of 3.25:1, and a lean meat percentage of 56.43%. Compared with the original Rongchang pig, the main economic trait indicators improved by 25%-63%, while the characteristics and traits of the local breed were maintained. This line has good adaptability and has already achieved considerable economic benefits in Sichuan, Beijing, Hainan, Gansu and other provinces and municipalities.
Jihe White pig
The Jihe White pig includes 2 specialized dam lines and 1 specialized sire line. Dam line A was produced by crossing three lines: Large White, Dingxian pig and Shenxian pig; dam line B was synthesized by crossing three lines: Landrace, Hangu Black pig, Taihu pig and Erhualian. Sire line C was developed by successive-generation single-line selection from American Hampshire pigs of 4 sources. The Jihe White pig adopts a three-line matching and two-stage crossbreeding method for commercial meat pig production. Line A is mated with line B to produce the parental generation AB, and AB sows are then mated with line C boars to produce the commercial generation CAB, all of which are fattened. All commercial pigs are white. Its characteristics are that sows have large litters, and commercial pigs have strong uniformity, high lean meat percentage and fast growth. The two dam lines A and B have litter sizes of 12.12 and 13.02 piglets respectively, average daily gains of 0.771 kg and 0.702 kg respectively, and lean meat percentages of 58.26% and 60.04% respectively. Sire line C has an average daily gain of 0.819 kg, a feed-to-meat ratio of 2.88:1, and a lean meat percentage of 65.34%. When the parental generation AB is crossed with sire line C, the litter size reaches 13.52 piglets; the commercial pig CAB reaches 90 kg at 154 days of age, with an average daily gain of 0.816 kg and a lean meat percentage of 60.34%, showing good prospects for promotion.
Landrace
Originally from Denmark, formerly called Landrace. Because of its long body and completely white coat, it is commonly known in China as the Landrace. In 1964, China first introduced it from Sweden; after many years of acclimatization, its body type shifted from refined to looser, its constitution shifted from delicate to robust, and its hooves became fairly solid. At 6 months of age, body weight is 83-85 kg, body length is 110.3-112.4 cm, litter size is more than 12 piglets, first-parity sows have a litter size of 10.8 piglets, and weaning litter weight is 107 kg. Through selection, all performance indicators of the breeding pigs have been improved. During the 20-90 kg stage, the average daily gain is 0.7 kg, the feed-to-meat ratio is 2.8:1, the dressing percentage at 90 kg is 75.3%, and the carcass lean meat percentage is 65%. The Landrace has characteristics such as fast growth, high feed utilization and high lean meat percentage, and sows also have a fairly large litter size and fairly abundant milk. The weaning litter weight is relatively high, and adaptability has improved somewhat after selection. This pig breed is found throughout China and, as an important sire breed, plays a major role in the crossbreeding and improvement of pig breeds in China.
Hubei White pig
Originally from Hubei, mainly distributed in the central China region. The Hubei White pig has a completely white coat that is fine, straight and long, ears that lean forward or droop slightly, a straight back and loin, a fairly long middle body, a small belly, full legs and hams, sturdy limbs and hooves, and more than 12 functional teats. Adult boars weigh 250-300 kg, and sows weigh 200-250 kg. This breed has characteristics such as high lean meat percentage, good meat quality, fast growth and development, and excellent reproductive performance. At 6 months of age, boars reach 90 kg body weight; during the 25-90 kg stage, the average daily gain is 0.6-0.65 kg, the feed-to-meat ratio is below 3.5:1, and 90 kg body weight is reached at 180 days of age; litter size is 9.5-10.5 piglets for first-parity sows and more than 12 piglets for sows after multiple parities. Using the Hubei White pig as the dam and crossing it with Duroc and Hampshire pigs both gives good combining ability, and the cross with Duroc pigs is especially effective. For Duroc x Hubei crossbred first-generation fattening pigs during the 20-90 kg body weight stage, the average daily gain is 0.65-0.75 kg, the heterosis rate is 10%, the feed-to-meat ratio is 3.1-3.3:1, and the carcass lean meat percentage is more than 62%. It is an excellent dam for crossbreeding utilization.
Zhejiang Middle White pig
The back coat is completely white, the body type is medium, the head and neck are fairly light, the face is straight or slightly concave, the ears are medium-sized and lean forward or droop slightly, the back and loin are fairly long, the belly line is fairly straight, the legs and hams are full in muscle, and there are more than 14 teats. Adult boars weigh 200 kg, and sows weigh 150-180 kg. This pig breed is a lean type, with excellent characteristics such as a robust constitution, fairly strong reproductive capacity, notable crossbreeding effects, and good adaptability to high-temperature and high-humidity climate conditions. It is a good dam for producing commercial lean meat pigs. Litter size is 9 piglets for first-parity sows and 12 piglets for sows after multiple parities. Body weight reaches 90 kg at 190 days of age, the average daily gain is 0.52-0.6 kg, the feed-to-meat ratio is 3.6:1, and the carcass lean meat percentage is 57%. Using the Zhejiang Middle White pig as the dam and crossing it with Duroc, Hampshire, Danish Landrace and Large Yorkshire pigs, the average litter size is more than 12 piglets; Duroc x Zhejiang crossbred pigs reach 90 kg at 175 days of age; during the 30-90 kg body weight stage, the average daily gain is more than 0.7 kg, the feed-to-meat ratio is below 3.3:1, and the carcass lean meat percentage is more than 60%.
Sanjiang White pig
This pig breed is a lean type, with characteristics such as fast growth, fairly large litters, high lean meat percentage, good meat quality and tolerance to cold climates. It is mainly distributed in the Sanjiang Plain area of eastern Heilongjiang Province, and is an excellent parent for producing commercial pigs and for crossbreeding utilization. This pig breed has a completely white coat on the back and body, a fairly long middle body, a relatively small belly circumference, a full hindquarter, and sturdy limbs. Adult boars weigh 250-300 kg, and sows weigh 200-250 kg. Replacement boars at 6 months of age weigh 80-85 kg, and replacement sows at 6 months of age weigh 75-80 kg. For fattening pigs during the 20-90 kg stage, the average daily gain is 0.6 kg, the age at 90 kg body weight is 185 days, the carcass lean meat percentage is 57%-58%, and litter size is 9-10 piglets for first-parity sows and 11-13 piglets for sows after multiple parities. The Sanjiang White pig has good combining ability when crossed with Duroc, Hampshire and Landrace pigs, and the cross with Duroc pigs is notably effective, with an average daily gain of 0.65 kg during the fattening period and a lean meat percentage of 62%.
Dekalb pig
The Dekalb specialized-line breeding pig is abbreviated as Dekalb (DEKALB), a breed that the American Dekalb company began developing in the 1970s. The Dekalb specialized-line breeding pig includes the great-grandparent generation (GGP), grandparent generation (GP), parent generation (PS) and commercial crossbred generation (MK). In May 1991, China introduced Dekalb specialized-line great-grandparent breeding pigs from the United States; they consist of five lines, respectively called A, B, C, E and F. These five lines are all purebred pigs and can be used for commercial meat pig production, giving full play to the genetic potential of specialized lines and obtaining maximum heterosis. The Dekalb pig has outstanding characteristics such as large litter size, fast growth, high feed conversion and high carcass lean meat percentage; in addition, it also has a series of advantages such as a sturdy constitution, uniform population, strong feeding ability, good meat quality and stress resistance. Litter size is 11.7 piglets for first-parity sows and 12.5 piglets for sows after multiple parities. The age at 90 kg body weight is 150 days, the feed-to-meat ratio is 2.8:1, the carcass lean meat percentage is 60%, and the dressing percentage is 74%. This pig breed is suitable for feeding and management and has good prospects for promotion.
Xiangbai pig
This pig breed is a new lean-type pig line selected and bred in Hubei Province during the "7th Five-Year Plan" and "8th Five-Year Plan". It has characteristics such as good production performance, genetic stability, tolerance to roughage, large litters, fast growth, high lean meat percentage and good meat quality, and is well received by producers and consumers. Sows after multiple parities have an average litter size of 12-12.5 piglets, fattening pigs reach 90 kg body weight at 180 days of age, and the carcass lean meat percentage reaches 57.5%. Commercial crossbred pigs produced by matching Xiangbai sows as the dam line with introduced Duroc boars reach 90 kg body weight at 160-170 days after birth under medium nutrition conditions, with an average daily gain of more than 0.7 kg during the fattening period, a feed-to-meat ratio of 3.0-3.2:1, and a carcass lean meat percentage of 60%-63%, which is 5-7 percentage points higher in lean meat percentage than ordinary three-way crossbred commercial pigs. It has now been promoted on a large scale in Hunan Province, and some has also been promoted to Guangdong and other places.