Study On Species' Characteristic Of Songliao Black Swine

The experiments were conducted to study the species'characteristic, blood physical and biochemical items, blood protease polymorphism, cell heredity regulation and molecular heredity regulation of Songliao Black Swine.The species'character of Songliao Black Swine were determined in the pig farm and the results indicated Songliao Black Swine was a developed breed with high reproductivity of big litter size, weight at birth and Weight of feeder pigs, the average litter size was 13.45±1.45,alive liter size born was 12.54±1.35,average birth weight was 1.37±0.12 kg,the weaning litter weight was 122.84±36.24 kg ;the growth and finishing performance were of 712.50±91.77g daily gain, 3.36±0.65 feed/gain, 68.19±2.50% dress percentage of commercial pig and 58.41±2.58% lean rate. After measuring body status, the results showed that development of body height was predominant in Songliao Black Swine in the early age, however, fat deposition in late age. Score of meat color and marble had a higher degree than that of Denmark Landrace with 2 scores. The pooled date also indicated that pork quality of Songliao Black Swine was fit to consumption's standard with palatable, suitable fat content characters. Analysis of heredity indexes showed that there was potential heredity of reproductivity of Songliao Black Swine herd because heredity of new born litter weight, piglet body weight, weaned litter weight, weaned body weight and tits were 0.427±0.058, 0.243±0.138, 0.382±0.138, 0.212±0.21 and 0.528±0.050, respectively. Results of relativity statistic indicated that weaned litter weight was a suitable candidate index to improve reproductivity of Songliao Black Swine, however, the phenotypic correlation was not to growth performance.A serial of experiments were conducted to study the blood index and protease polymorphism. The results showed that several blood indexes of Songliao Black Swine were normal according the reports before. Analysis of relativity between indexes and growth performance was there was a negative relation between daily gain and triglyeride, moreover, the same relationship existed between lean rate and carnine, Ham ratio of carcass and carnine. In the aspects of protease polymorphism, there was polymorphism in the Pa1,Po1,Po2,Tf,Ptf,Am1,Am2,Akp,Es and Hpx except Alb,Cp and Pa2. There were Po1,Po2,Tf,Am1,Am2,Hpx and Es in of Hardy-Weinberg balance except Pa1,Pa2,Ptf and Akp after checking of chi-square criterion. After genetic variance analysis of herds, the data of H, Ne and H.I. were 0.5085, 2.0779 and 0.1288, respectively. The results indicated that there was great genetic variance in Songliao Black Swine herds.There were some certain regulations in the relativity between protease loci and some traits. There was a positive effect of serum prealbumin 1(Pa1) on length of carcass, shin thickness and cooked pork with genotype BB, the similar results was also found serum postalbumin1(Po1) with genotype AA on body height,carcass length and water losing rate. There was positive effect of Po2 , a gene of serum postalbumin2(Po2), on chest circumference; moreover, there was a same tendency in effect of serum transferring(Tf) on marbling evaluation with genotype AC. There was a significant difference of serum alkaline phosphatase (Akp) among genotypes, genotype DD had a negative effect on carcass length, however, the allele AkpD had positive effect on carcass length, furthermore, there was a positive effect of genotype DD on water losing rate, yet. There were different effect of serum amylase1(Am1) with different genotype on lean rate and eye area. There was a positive effect of allele Am1A on lean rate and eye area, however, allele Am1C had a negative effect on lean rate and eye area, moreover, there was a positive effect of AB genotype on water losing rate. There were some positive effect of serum amylase2(Am2) genotypes on traits, such as AA on body height and lean rate, AB on chest circum and back fat thickness, BB on cooked pork rate, and so on. Serum esterase(Es) had a significant difference in genotype, for example, there was a positive effect of AB genotype on carcass length, but AA genotype had negative effect on eye area.Cell heredity characters were studied and results showed that diploid chromosome number of Songliao Black Swine was 2n=38 after determination of diploid chromosome number. The morphology characteristic of C band was circle mostly, and there as a similar C band polymorphism between Songliao Black Swine and reports before.In the study of molecular heredity of Songliao Black Swine, the loci polymorphism of exon -4 of IGF-1 were determined and the relativity between exon-4 and a part of growth-finishing traits was analyzed. The results indicated that there was a plenty of genetic polymorphism of exon-4 and there was positive effect of exon-4 allele on average daily gain. Analysis of polymorphism of H-FABP'5'-upstream and intron-II , moreover, the relativity between the polymorphism and IMF indicated that HHdd combination improved IMF content with effect of improving pork quality. The muscular fat content of swine with genotype TT was higher than that of swine with genotype CT(P<0.05), and the same result in the lean rate(P<0.05),which showed that gene frequency of T was predominate(0.82) and T gene benefited to average back fat thickness, muscular fat content and lean rate. In the study of relativity of FSH? loci polymorphism and reproductivity, there was a significant difference of litter size between genotype EE and EF(P<0.05), allele of F was predominate(0.7833), and conclusion could be drawn that FSH? was a candidate gene to control the reproductivity of Songliao Black Swine.