Polymorphisms of osteopontin gene and their association with placental efficiency and prolificacy in goats

Abstract

In this study, we investigated the polymorphisms of Caprine osteopontin (OPN) gene and their association with placental traits and prolificacy in goats. The placental and reproductive traits of 171 litters on three goat breeds with different prolificacy (Dazu Black, n = 94; Lezhi Black, n = 27; Hexi Cashmere, n = 50) were evaluated. The polymorphisms in the 5′ promoter and exon 7 of OPN gene were detected by PCR-SSCP methods. Their association was further achieved by using least squares means. It showed that the litter size, litter and placenta weight for Dazu Black and Lezhi Black goats were higher significantly than those of Hexi Cashmere goats (P < 0.01). However, the placental efficiency was not significantly different (P > 0.05). Hexi Cashmere does have more cotyledons in placental than that of Dazu Black and Lezhi Black does (P < 0.01). There were only two genotypes (nominated AA and AB) detected whether by the 5′ promoter primer pairs or by exon 7 of OPN gene. They were associated with litter number, with a trend of AA > AB. At the exon 7 locus, the Dazu Black does with genotype AA had 0.88 more litter numbers than those with genotype AB (P < 0.05). It suggested that OPN gene could be a potential candidate gene on goat prolificacy.

Keywords:

• goat
• placental efficiency
• litter size
• osteopontin (OPN)

Acknowledgements

The authors thank Dr Jian Wang for technical assistance during the project, and Dr Xiaochuan Chen for helpful discussions about the placental analysis.