Association of LEPR polymorphisms with egg production and growth performance in female Japanese quails

Abstract

This study aimed to screen intron 8 of the leptin receptor (LEPR) gene for polymorphisms in female Japanese quails. Two adjacent novel SNPs (A277G and A304G) were detected using PCR-SSCP and sequencing. These SNPs produced three haplotypes (AA/AA, AG/AG, and GG/GG) that were significantly (p ≤ 0.05) associated with growth and egg production traits. GG/GG haplotype-quails had significantly (p ≤ 0.05) lower egg production, feed intake, growth performance, lipid profile, serum levels of sex hormones (estradiol, progesterone, FSH, LH), and ovarian expressions of survivin, FSHR, and IGF1 than other quails. However, GG/GG quails had significantly (p ≤ 0.05) higher serum levels of LEP and mRNA levels of LEPR, LEP, and caspase 3 in the hypothalamus and ovaries. These higher levels of LEP/LEPR could not only reduce feed intake and body weight gain but also could induce apoptosis of ovarian cells (as indicated by lower survivin and IGF1 and higher caspase3 expression) which could inhibit the development of the follicles and the release of sex hormones with a subsequent decrease in egg production in GG/GG quails. Therefore, with these results, we suggest selecting Japanese quails with AA/AA and AG/AG haplotypes to improve the reproduction and growth performance of this flock.

Keywords:

• LEP
• LEPR
• egg production
• growth traits
• SNPs

Acknowledgment

No fund was received to conduct this study.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Author contributions

This article has not been submitted anywhere else for publication. MEy, AS, conception, design of study, conducting the production experiment, interpretation of data, statistical analysis; AS, design of study, conducting the molecular experiment, interpretation of data; IE, collection of samples, conducting the production experiment; MEd, design of study, conducting the molecular experiment, article preparation. All coauthors approved the final draft of the article.