Genetic variation in growth and the optimisation of SNP molecular markers for parentage assignment in pasture-based crossbred sheep

Abstract

Genetic variation in post-weaning growth and body conformation of first cross Merino prime lambs sired by Dorset, White Suffolk and Black Suffolk rams and the optimisation of single and multiplex SNPs for parentage assignment was investigated. Significant variations (P<0.01) attributable to sire genetics, gender and their interactions were detected; White Suffolk × Merino lambs had the highest average daily gains, chest girth and body condition scores of 0.17 kg/day, 83cm and 3.1, respectively. Genomic DNA extracted from wool had the highest yield and purity ranging from 385-425 ng/µl (purity ratio of 1.6-1.9) than blood genomic DNA. The optimal annealing temperature for PCR interrogation primers in a multiplex combination of 4 SNPs was 65ºC run on a 3% agarose gel for 90 minutes. Furthermore, SNP primers 375, 382, 497 and 586 proved reliable in obtaining clear-cut bands. It was concluded that there is scope for utilizing a multiplex of up to 10 SNPs in a Beckman Coulter Platform to genotype and successfully assign crossbred sheep to their parents.