Exploring genetic variability and its association with growth traits in Rohilkhandi goats.

Goats offer unique social, economic and biological benefits compared to other livestock species and are often referred to as the “poor man’s cow”. This study aimed to examine the polymorphism of six gene loci, namely IGF1, GH1, GH2, MSTN, IGFBP3 and GDF9, in Rohilkhandi goats using PCR-RFLP and assessed their association with various growth traits like body weight measured from birth to 48 months of age. Polymorphism was detected only in IGF1, GH1 and MSTN, whereas GH2, IGFBP3 and GDF9 were monomorphic in this population. Body weight, as an indicator of growth traits, increased significantly from 2.17 ± 0.04 kg at birth to 28.55 ± 0.32 kg at 48 months of age. Association analysis showed that IGF1 genotypes were related to body weight across all age points (p < 0.05, p < 0.01 and p < 0.001), with the BB genotype exhibiting higher mean body weights. GH1 genotypes showed effects only at 9 and 15 months and MSTN exhibited genotype-body weight associations at multiple ages across the growth period (p < 0.05, p < 0.01 and p < 0.001), with the AA genotype consistently showed higher body weight than BB. Although the study was based on a modest sample of female goats from a single herd, the consistent trends observed across age points provide a valuable initial indication of genotype-growth relationships in Rohilkhandi goats. The patterns detected for IGF1 and MSTN highlight their potential biological relevance for growth performance. Building on this foundation, future multi-herd studies with larger and more diverse populations will be important for confirming these promising signals and refining their usefulness for genetic improvement programs.