The Effects of SNPs in the LCORL and LTBP2 Genes on Comprehensive Performance Traits in Charolais Sheep

Detection of the DGAT1 Gene Variation and Its Association with Growth Traits in Degeres Sheep

Simple Summary Sheep are an important source of meat in Kazakhstan, and improving their growth and meat quality can benefit both farmers and consumers. One way to achieve this is by identifying genes that influence these traits. In this study, we examined four genes involved in growth, muscle development, and fat metabolism in Degeres sheep. We measured how these genes were expressed in different body tissues and searched for polymorphisms that are associated with growth traits. We identified a genetic variation in one gene (DGAT1) that was associated with chest width, an important growth characteristic. The results suggest that this variant might be useful for selecting sheep with desirable growth traits in future breeding programs. Additional studies involving larger numbers of animals are needed to confirm these findings before they can be applied in sheep breeding.

Complex combination of polymorphic variants of the OPN and IGF-1 genes in a cattle population

The article presents the results of a study on the combined genotypes of OPN (c.8514C/T) and IGF-1 (512T/C) genes in a population of Holstein heifers (n=202). The experiment was conducted at the Lenin Breeding Farm (Atninsky District, Republic of Tatarstan), and laboratory analyses were carried out at the Tatar Research Institute of Agriculture, Kazan Scientific Center of the Russian Academy of Sciences. The relevance of the study is driven by the need to identify genetic markers associated with reproductive traits in cattle, as fertility indicators alongside milk productivity determine the economic efficiency of dairy farming. The OPN and IGF-1 genes are involved in the regulation of embryogenesis, implantation, folliculogenesis, and early embryonic development; however, their combined interaction remains insufficiently studied. Genotyping was performed using PCR-RFLP with restriction endonucleases BseI (for OPN ) and BstSNI (for IGF-1 ). The analysis revealed the presence of all nine possible combined genotype combinations, confirming the genetic heterogeneity of the studied population. The highest frequency was observed for the combined genotype CT/AB (29.7%), while the lowest frequencies were found for CC/BB (2.0%) and CC/AA (3.0%) by OPN / IGF-1 . A pattern of decreasing frequency of combined genotypes was established with an increasing number of homozygous loci. Comparison of the observed and theoretically expected distributions showed no statistically significant deviations (χ² = 4.67; p > 0.05), indicating independent allele combination of the studied genes and the absence of factors disrupting genetic equilibrium in the sample. The obtained data can be applied in breeding programs for marker-assisted selection of parental pairs, genetic passportization, and monitoring of the genetic structure of cattle populations.

Complex SNPs of leptin and somatotropin and their association with economic traits in cattle

The aim of the study was to evaluate the effect of 12 complex GN and LEP genotypes on cow productivity in order to identify consistently effective allele combinations that account for genotype-environment interactions, and to develop personalized strategies for herd breeding and management. The conducted study revealed a significant association between complex genotypes of the somatotropin (GH, LV polymorphism) and leptin (LEP, R25C and A80V polymorphisms) genes and milk productivity in Holstein cows. A study of 120 animals (60 animals each from two agricultural organizations) showed a marked uneven distribution of the 12 analyzed genotypes in both herds, due to the farm breeding priorities. A key result was the identification of the GHLVR25CRRA80VAA genotype as the most promising for breeding for high lifetime milk productivity. Animals with this genotype consistently demonstrated maximum milk yields in the first and third lactations and lifetime productivity, demonstrating stability and high genetic potential. In parallel, genotypes associated with milk quality traits were identified. For example, in animals carrying the GHLVR25CCCA80VVV genotype at Organization "K," the lifetime fat and protein content was 3.92 and 3.27 %, respectively. Animals with the GHLVR25CCRA80VAA genotype in Organization "P" had a maximum fat content of 4.13 % while maintaining high milk yield. The study confirmed the critical influence of environmental factors (feeding, management) on the realization of genetic potential. The significantly higher milk yields in Organization "P" compared to Organization "K" highlight the need for a systematic approach combining genetic selection with improved livestock production technologies. The obtained data demonstrate that the complex GH and LEP genotypes serve as informative markers for predicting milk productivity and the adaptive potential of cows.

Characterization of IGF1 gene marker as potential genes in improving growth performance of Indonesian goats

Background: Goat farming development begins with the availability of genetically and phenotypically superior livestock to ensure optimal productivity and reproduction. Aim: This study aimed to identify polymorphisms in the IGF1 gene and to evaluate their association with growth performance. Methods: A total of 105 goats were sampled, including 35 individuals from each of three Indonesian goat breeds: Peranakan Etawah (PE), Jawarandu, and Kacang, aged between 12 and 24 months. Growth parameters measured included body weight and morphometric characteristics. Genetic variation of the IGF1 gene was analyzed using Sanger sequencing. Morphometric data were analyzed using principal component analysis (PCA) in R software to explore variation patterns, while associations between IGF1 gene polymorphisms and growth traits were evaluated using analysis of variance (ANOVA). Results: Sequence analysis revealed significant nucleotide variations at certain positions, indicated by overlapping guanine (G) and thymine (T) chromatogram peaks, indicating a heterozygous genotype (G/T) at this locus. The IGF1 gene has diverse genotypes in all goat breeds, namely GG, GT, and TT. All genotypes were present except in the JW breed, where the TT genotype was absent. IGF1 gene diversity was significantly associated (P<0.05) with morphometric characteristics, including muzzle circumference, head length, ear length, ear width, rump length, and leg circumferenc. The GT genotype had the highest morphometric performance compared to the other genotypes. Conclusion: The IGF1 gene may serve as a potential candidate marker for marker-assisted selection (MAS) to improve the growth performance of Indonesian goats, although further validation is required.

Frequencies of the variants associated with the calpain and calpastatin genes in Brazilian Brahman cattle

Abstract The objective of this work was to estimate the frequency of favorable genotypes in the gene markers CAPN1 316, CAPN1 4751, CAPN3, and CAST c.2832 in Brazilian Brahman cattle. A total of 108 DNA samples from purebred Brahman cattle were analyzed to genotype the animals for each marker through polymerase chain reaction and direct Sanger sequencing. These samples were originated from 54 bulls and 54 cows used as semen and oocyte donors, respectively. The genotype frequencies, known to be associated with meat tenderness, were 48% AA in CAST and 14% GG in CAPN3. CAST has been used in the selection of animals with a meat tenderness phenotype across various cattle breeds, including Brahman cattle from other countries. The CC genotype, which is favorable in CAPN1 316 and CAPN1 4751, was not identified in the analyzed samples. The highest prevalence of the AA genotype in CAST observed in bulls and cows used in purebred breeding programs in Brazil indicates that this marker can be used to guide mating strategies in order to increase the frequency of this genotype and enhance meat tenderness.

Uncovering genetic markers for growth and fat-tail traits in Kurdi sheep: associations with DGAT1 and PPARGC1B variants