Objective Polymorphisms of ESR and FSHβ and relation of the genes with low litter size of otherwise robust Tibetan pig were investigated.

Method Polymorphisms of FSHβ and ESR in randomly selected 66 Tibetan pigs were detected using the PCR-RFLP method to correlate with the animal reproductive performance.

Result Significant polymorphisms were found in the genes. In ESR, the frequency of AA genotype was 0.152, that of AB genotype 0.288, and that of BB genotype high at 0.560. Statistically, the frequency of allele A in ESR was 0.296, and that of allele B, 0.704. Thus, BB was the dominant genotype and B the dominant allele. On the other hand, in FSHβ, the frequencies were 0.379 for AA genotype, 0.288 for AB genotype, and 0.333 for BB genotype, while those for allele A were 0.523 and for allele B 0.477. Thus, AA genotype and A allele were dominant in FSHβ. The association analysis suggested that the ESR-BB and FSHβ-AA genotypes contributed significantly to the low litter size of the pigs (P＜0.05).

Conclusion The B allele of ESR and the A allele of FSHβ could potentially be served as the genetic markers for breeding selection to improve the reproductivity of Tibetan pigs.