47 - Genomic Studies of Reproductive Performance in American Mink

Improving reproductive efficiency is one of the main breeding goals in mink farming. Understanding the genetics of reproductive performance is essential for the development of effective breeding programs in mink. The objectives of this study are to 1) estimate the phenotypic and genetic parameters for litter sizes (LS), mortality rate at birth. (MB) and gestation-length (GL) traits; 2) perform genome-wide association studies (GWAS) for these reproductive traits; 3) implement GWAS results in the selection of mink for reproductive performance; 4) explore the potential for genomic selection in mink. The detailed reproductive performance on 3,500 female mink has been collected at the Canadian Center for Fur Animal Research at Dalhousie University (Truro, NS, Canada), in which, 1,000 of them will be genotyped with Affymetrix 50k SNP panel. A series of univariate and bivariate analyses were implemented in ASREML software to estimate the genetic and phenotypic parameters. Heritability estimates (±SE) were low-to-moderate, ranged from 0.06±0.02 for total number born to 0.23±0.03 for GL. High positive genetic correlations (±SE) were observed between LS traits, ranged from 0.59±0.18 to 0.85±0.11. There was a moderate genetic correlation (±SE) between MB and total number of kits born (0.46±0.15). However, MB had a favorable strong negative genetic correlation (±SE) with the number of weaned kits (–0.75±0.16). These estimated genetic parameters can be incorporated into Canadian mink breeding programs. Considering the low-to-moderate heritability of reproduction traits, the availability of the mink reference genome and genotyping panel will provide opportunities to accelerate mink breeding through genomics. The results of this project will contribute significantly to the current genetic knowledge of reproductive traits and identify the opportunities for genetic improvement through the application of genomics. The overall project aim is to develop a cost-effective, low-density panel of markers for the implementation of genomic selection for reproductive performance in mink.