Basic Research On Several Breeding Characteristics In Yunan Black Pig

Huainan Pig is an excellent local breeds in Henan province which were protected through builted conservation farms in its main production area——Gushi county in 1978. And the Huainan Pig Breeding Collaboration Unit was setted up by animal husbandry bureau of Henan province in 1986 to carry out the purebred breeding work which gained good achievements. Entering into the 1990s, the Huainan pig can not adapt to the development of modern pig industry because of its character of growing slowly and other reasons. After repeated demonstration and test, the new variety of Huainan pig, from Huainan pig as female parent with duroc pig as male parent was bred. The filial generation of duroc boar and Huainan sow were F1. And the filial generation of grading crossing by duroc boar and sow from F1 generation were F2. Then take the offspring which come from the reciprocal cross of F1 and F2 as the foundation stock of the new breed——Yunan black pig. The ideal individuals which chosed from the foundation stock were formed a core herd in zero generation by transverse crossing fixed method, and after the population subculture breeding in the incomplete atresia situation, the Yunan black pig was bred by extending the group.Fundamental research of some characteristic in Yunan black pig were studied in order to test and verify the characteristic of the Yunan black pig which was elaborately bred through 16 years and provide conveniences to the next breeding and popularizing work. The domain of research included four aspects, such as growing-finishing, physiological and biochemical indicators, carcass and meat quality. And the whole research was consist of four tests. The test one is the study of growing-finishing in Yunan black pig, 60 Yunan black pigs and 20 crossbreed pigs (Landrace×Yorkshire) were raised until 100㎏ to measure some indexes, e.g. feed intake,average daily gain and feed/gain;The test tow is the study of physiological and biochemical indicators in Yunan black pig, four farrowing piglets were measured rectal temperature,heart rate,breathing rate from birth day to 2-month-old, at the same time, 16 blood samples of 6-8 months Yunan black pig were analyzed physiological and biochemical indicators; The test three is the study of carcass of Yunan black pig, when put over the test one, slaughter 16 Yunan black pig which body weight approximate 90㎏ to analyze some indexes, f.g. dressing percentage,loin eye area,backfat,lean percentage etc; The test four is the study of meat quality in Yunan black pig, 40 meat samples from Yunan black pig(16),crossbreed pig(Yorkshire×Landrace, 4),Huainan pig(10),Duroc(10)to analyzed meat quality, f.g. meat color,marbling,tendenss,drip loss,cooking percentage,intramuscular,fatty acid,Myofiber etc. The results showed that the average daily gain (598.76g VS 688.96g), lean meat percentage(56.08% VS 64.02%),longissimus dorsi area(31.77cm2 VS 46.38cm2), heart weight(0.34kg VS 0.40kg),small intestine length(1725.62cm VS 2157.50cm),100kg revised blackfat thickness(29.57mm VS 20.75mm) and fleshcolor(17.78 VS 13.42) were significantly different between Yunan Black pig and the crossbreed pig(Yorkshire×Landrace)(P<0.01).In particular, the intramuscular fat content of Yunan Black pig was higher than the crossbreed pig(Yorkshire×Landrace)(P<0.05).100kg day of age (207.10d VS 197.41d), average daily lean meat gain (298.79g VS 318.29g), feed/gain (2.86 VS 3.33), dressed carcass percentage (74.67% VS 74.80%) and blood traits et al, were not different (P>0.05).Unsaturated fatty acids content of crossbreed pig is 64.29%, including palmitic acid and stearic acid primarily. And the content between mono unsaturated fatty acids and polyunsaturated fatty acids was primary the same. Additionally, relative content of fatty acid in the crossbreed pig(Yorkshire×Landrace) was as much as the paternal Duroc, while its polyunsaturated fatty acid content was in accordance with the female parent Yunan Black pig.The average daily gain (631.51g VS 562.24g), feed/gain (2.73 VS 2.99) and longissimus dorsi area (28.59cm2 VS 34.96cm2) were significantly different between the hog and the saw in Yunan Black pig (P<0.01), while the 100kg day of age (203.20d VS 217.79d) and lean meat percentage (54.19% VS 57.98%) were different(P<0.05).Among the piglet of Yunan Black pig, the heart rate (77.24 VS 67.28), respiratory frequency (72.02 VS 67.64) and rectal temperature were significantly different between the male and the female(P<0.01), the respiratory frequency and rectal temperature of the matural pig as well (P<0.01). Furthermore, the muscle fiber diameter (59.76μm VS 51.22μm) and area (2482.69μm2 VS 1840.76μm2) of the hog were greater than the saw, while the muscle fiber density (261.78 stick/ mm2 VS 271.13 stick/ mm2,or 36.50 stick/fascicle VS 50.75 stick/fascicle) of the male was less than the female.In conclusion, 1) body type, growth rate and lean meat percentage of Yunan Black pig achieve the breeding objective and conform to the breeding criterion of lean meat model in swine, which can be popularized as a breed of lean meat model; 2)The physiological characteristics of Yunan Black pig tends to be stable. Response to heat stress, the male piglet was more adaptable than the female, while the matural female pig was more adaptable than the male; 3)The development capacity of heart, small intestine and large intestine of Yunan Black pig was less than the crossbreed pig(Yorkshire×Landrace),which may restrict the growth rate of Yunan Black pig; 4)Pork of Yunan black pigs have flesh bright coloure,rich marbling,high intramuscular fat,better water holding capacity,character hard traits;5) Pork of Yunan black pigs have more saturated fatty acid,it maybe a cause of good meat flavor.