Studies On The Relationship Between Swine Reproduction Performance And Osteopontin Or Estrogen Receptor Gene

52 Erhualian and 41 Suzhong sows were selected to explore the relationship between sow reproduction performances and osteopontin or estrogen receptor gene. The results were as follows:1 The relationship between osteopontin gene polymorhpism and reproduction performance of sowsThe aim of the study was to investigate the effect of the osteopontin gene on reproductive traits in Suzhong and Erhualian swine lines by means of PCR, polyacrylamide gel electrophoresis and sliver staining. More than 660 litter records from 93 sows genolyped at osteopontin locus were analyzed to determine whether osteopontin gene influenced total number born (TNB) or number born alive (NBA). Number of alleles and average effective number of alleles were counted. According to the allele frequencies of OPN microsatellite locus, polymorphism information content (PIC) and mean heterozygosity were calculated for each line. 168, 170, 152 and 142 allele frequencies of Suzhong sows and 152, 164 and 158 allele frequencies of Erhualian sows are high. TNB between Erhualian sows with 158/142 and with 170/152 or 168/140 genotype and NBA between 158/142 and 170/152 genotype are significant difference in later parities (P<0.05). NBA between Suzhong sows with 164/168 and with 140/152, 142/168, 152/170 genotype is significant difference in first parity (P<0.05) and NBA between 152/170 and 130/142 genotype is significant difference in later parities(P<0.05).The PIC, number of efficient alleles and heterozygosity of OPN gene of Erhualian sows is 0.82, 6.20 and 0.84 respectively and higher than that of Suzhong sows which is 0.78, 5.23 and 0.81, respectively. There is a polymorphism of osteopontin gene in Suzhong and Erhualian swine lines. TNB of Erhualian sows in later parties with 170/152 and 168/140 genotype and NBA with 170/152 are large. NBA of Suzhong sows with 140/152, 142/168 and 152/170 genotype is large in all parities and TNB with 152/170 genotype islarge in later parities. TNB and NBA of both Suzhong and Erhualian sows with 152/170 genotype are large. Effect of different genotype of OPN on TN of Suzhong sows and average body weight at birth (BWB) of their piglets in later parities is remarkable.2 The relationship between estrogen receptor gene polymorphism and reproduction performance of sowsTo investigate the effect of the estrogen receptor (ESR) gene on reproductive traits in Suzhong and Erhualian swine lines, more than 660 litter records from 93 sows genotyped at ESR locus were analyzed to determine whether ESR influenced TNB or NBA. The frequency of A and B allele of Suzhong sows was 0.54 and 0.46 respectively, and the frequency of A and B allele of Erhualian sows was 0.31 and 0.69, respectively. TNB and NBA showed significant difference among Erhualian sows with different genotype in first parity and TNB showed significant difference among Suzhong sows with AA and AB, BB genotype in first parity. TNB and NAB were significant different between Erhualian sows of later parities with AB and BB genotype.The B allele frequency of ESR gene in Erhualian sows is high and has a close relativity to TNB and NBA. The trend of TNB and NAB of Erhualian sows in all parities is genotype BB>AB>AA. There is also same trend in Suzhong sows in first parity, but not so remarkable as that of Erhualian sows.The result of combination of OPN and ESR genotype on litter size of Suzhong and Erhualian swines was indicated that OPN gene effect is isolated and not controlled by ESR gene. They can become markers to improve swine reproduction performance.