Growth Hormone (GH) and Insulin like Growth Factor-I (IGF1) are members of somototrophine axis pathway. They play a role in key on several mechanisms such as postnatal growth, cell differentiation and metabolism. Due to their vital importance, polymorphisms on the genes coding are worth to be understood. In this study five native cattle breeds (Native Southern Yellow (NSY), South Anatolian Red (SAR), Anatolian Grey (AG), Native Black (NB), East Anatolian Red (EAR) were investigated by PCR-RFLP method for GH-MspI and IGF1-SnaBI loci. 198 and 194 samples were analyzed for GH-MspI and IGF1-SnaBI loci, respectively. In both two loci two alleles and three genotypes were observed. Predominant alleles were A and B for GH-MspI locus IGF1-SnaBI loci, respectively. Frequencies of A and B alleles were calculated between 0.400-0.875 and 0.846-0.903 for GH-MspI locus IGF1-SnaBI loci, respectively. While among investigated population only EAR population was at Hardy-Weinberg equilibrium for IGF1-SnaBI locus, for GH-MspI only, in SAR population no deviation from Hardy-Weinberg equilibrium.

Changing climatic conditions and growing population size lead take precautions against potential risks. Researchers who study in the agricultural field, including animal production, focus on finding out variants and breeds resistant to diseases and environmental stress. Detecting gene regions that affect resistance to diseases and environmental stress might increase the performance of the selection in favor of these traits. Due to these reasons in this study, five Turkish native cattle breeds were investigated for SNPs belonging to TLR2, NOD2, and IFNγ (using EcoRV, BsaHI ve HphI enzymes, respectively) reported to be associated with paratuberculosis previously. In total, 169 animals were analyzed from Native Southern Yellow (NSY= 29), East Anatolian Red (EAR=35), Anatolian Grey (AG=36), South Anatolian Red (SAR=34), and Native Black (NB=35). The genotype and allele frequencies were calculated with the PopGene32 program, and Khi square test was performed to determine whether the populations were in Hardy-Weinberg equilibrium (HWE). While at TLR2- EcoRV and NOD2- BsaHI loci, two alleles (A and C, C and T, respectively), IFNγ- HphI locus was found to be monomorphic for the G allele. For TLR2- EcoRV locus, the C allele was found as predominant except NB breed, and the C allele was predominant for all breeds at NOD2- BsaHI locus. However, in all breeds, NOD2- BsaHI locus was at HWE, for TLR2- EcoRV NSY and SAR breeds showed derivation from HWE.

This study was performed to determine the genotype and allele frequencies and the association between the leptin gene Sau3AI polymorphism and some performance traits in Simmental (n=60) and Brown Swiss (n=62) cattle in the province of Erzurum, Türkiye. Considering the allele frequencies in the population, the frequency of the A allele was 0.87 and the frequency of the B allele was 0.13 in Simmental cattle, and the frequency of the A allele was 0.94 and the frequency of the B allele was 0.06 in Brown Swiss cattle. According to the analysis conducted in the Simmental breed, the general averages were found to be 5422.4 ± 1901.74 kg for actual milk yield, 5626.6 ± 1475.85 kg for 305-day milk yield, 298.7 ± 84.80 days for lactation duration, and 18.5 ± 4.84 kg for daily milk yield. As a result of the analysis in the Brown Swiss breed, the general averages were 3917.8 ± 1584.38 kg for actual milk yield, 4614.3 ± 982.62 kg for 305-day milk yield, 254.9 ± 99.88 days for lactation duration, and 16.0 ± 3.82 kg for daily milk yield. According to the statistical analysis results, the impact of genotype on milk yield traits was insignificant in Simmental and Brown Swiss cattle.