Study of the Association Between SNPs and External Pelvimetry Measurements in Romanian Simmental Cattle

The evaluation of external pelvimetry measurements and the genetic factors influencing them is essential for improving morphological characteristics and reproductive performance in cattle. This study represents the first comprehensive analysis of the association between single nucleotide polymorphisms (SNPs) and external pelvimetry traits in Romanian Simmental cattle, a breed recognized for its distinctive pelvic morphology. The relationship between single-nucleotide polymorphisms (SNPs) and external pelvimetry traits-including croup height (CH), buttock height (BH), croup width (CW), rump angle (RA), and croup length (CL)-was examined in Simmental cows. From an initial set of 110 SNPs, 33 markers were retained after applying quality control filters, including a minor allele frequency (MAF) greater than 0.05 and Hardy-Weinberg equilibrium. These SNPs, located on multiple chromosomes, were identified within intronic, exonic, or regulatory regions of relevant genes such as CLSTN2, DPYD, FBXL7, FBXL13, SEMA6A, RUNX2, FSTL4, DST, DCBLD2, FRMD6, CAV2.3, ABL2, SH3BP4, RSBN1L,and SAMD12, suggesting that these genetic variants may influence the development and morphology of the pelvic bones. Statistical analysis revealed significant relationships between certain allele variants and croup measurements, highlighting that the presence of alternative alleles can modify their morphological traits. Notably, the G allele in CLSTN2 reduced croup height by 5.74 cm (p = 0.0227), while the T allele in RUNX2 decreased rump angle by 4.49° (p = 0.0119).