The aim of the study was to assess the genetic potential in Canadian Hereford sires using DNA markers, identify complex genotypes and assess their impact on the growth, development and meat productivity of its offspring. Groups of sons were formed taking into account the complex genotypes of sires: group 1 (n = 28) – sons of bulls carrying in their genome a complex of genotypes with desired alleles; group 2 (n = 30) – sons of bulls with a complex of genotypes that lack the desired alleles. The offspring from bulls-carriers of the “desirable” alleles in complex CAPN1, GH, Lep, TG5 genes that meet the exterior requirements exceeded their peers in live weight (P < 0.05), carcass weight (P < 0.05) and muscle tissue (P < 0.05). The maximum conversion rate of feed protein into product protein was also established in the group of sons from selected bulls. Thus, animal selection for body conformation type is advisable to combine with the herd genotyping for a complex of genotypes associated with different economically useful traits when creating highly efficient population of beef cattle.
The purpose of research was to study the association of polymorphic variants of growth hormone gene with development, slaughter traits and carcass composition in crossbred Red Angus × Kalmyk bull-calves. The experiment was carried out at LLC “Agrofirma Aduchi” in Republic of Kalmykia. The object of the study was crossbred Red Angus × Kalmyk (F2) bull-calves. The use of Red Angus sires with a high concentration of G allele in GH gene in the reproduction system of a herd made it possible to obtain second-generation crossbred progeny with a genotype distribution of 0.0625: 0.5: 0.4375, respectively, VV: LV: LL. The frequency of V allele reached 0.3125. The superiority of heterozygous individuals in live weight reached 18.0 kg by the age of 18 months (P>0.05). The maximum carcass weight was established in the group of heterozygous individuals, their superiority was 25.3 kg (P <0.01). The advantage in carcass yield of carriers of the minor allele V was 1.7% (P<0.05). The heterozygous animals were superior in flesh part weight in half-carcass by 11.1 kg (P <0.001). A less pronounced intergroup difference was found in bone weight, which reached 1.2 kg (P> 0.05). The monitoring the genetic structure of the herd taken into account the allelic distribution in growth hormone gene will provide the development of meat productivity potential.
Background and Aim: The leptin (LEP) gene plays a role in the regulation of the activity required to obtain food, energy metabolism, and fat deposition and affects the body composition of animals. Lipogenesis is an ineffective process. A lot of energy from feed is expended on the synthesis of adipose tissue. This study aimed to determine the effect of LEP C528T and LEP C73T polymorphisms and pregnancy on adipose tissue formation and carcass grade in Aberdeen Angus heifers and first-calf cows. Materials and Methods: Heifers (n = 49) and first-calf cows (n = 30) were grouped according to their genotype for LEP C528T and LEP C73T polymorphisms at the age of 24 months. DNA samples were isolated from whole blood. Experimental animals were slaughtered at the age of 24 months, and a chemical analysis of samples of longissimus dorsi muscle and ground beef was performed. Results: The maximum internal fat weight, back-fat thickness, and fat content of the longissimus dorsi muscle and ground beef were determined in heifers heterozygous for both LEP C528T and LEP C73T polymorphisms. The ranking of genotypes in terms of adipose tissue formation did not change in first-calf cows compared to heifers carrying the same LEP gene variants. Pregnancy had a more significant (p < 0.05–0.001) effect on slaughter parameters and lipogenesis in animals of different genotypes than studied polymorphisms. Heterozygosity of the LEP gene was much more strongly expressed in the carcass grade of heifers. "Prime" grades were assigned to 66.7% of carcasses heterozygous for LEP C528T and "Top Choice" to 58.8% of carcasses with LEP C73T nucleotide substitutions. Conclusion: LEP C528T and LEP C73T polymorphisms were shown to affect the extent of fat formation in Aberdeen Angus heifers and first-calf cows. Animals with heterozygous genotypes exhibited the maximum development of internal fat, back-fat, and intramuscular fat. Pregnancy had a more significant effect on slaughter parameters and adipose tissue formation than studied polymorphisms. First-calf cows had a significantly lower fat content in carcasses than heifers. These results can aid in the production of efficient mature herds of Aberdeen Angus cattle.
The aim of our research was to study the effect of single-nucleotide polymorphisms in growth hormone gene on variability of weight and linear growth in crossbred Red Angus × Kalmyk heifers (F2). The experimental animals were reared in "Agrofirma Aduchi" Ltd. in Tselinniy region, Republic of Kalmykia. Heifers were divided into groups after genotyping in accordance with the allelic variant of the growth hormone gene: I group completed with GH LV heterozygous animals (n = 11 heads), II grouprepresentatives of the homozygous GH VV gene (n = 9 heads). The inter-group differences in live weight were insignificant (P> 0.05) between the carriers of various genotype variants in growth hormone gene in the weaning age (8 months). The advantage in live weight between experimental animals increased to 23.9 kg (P <0.05) at the final stage of the control rearing (18 months). In this period, heterozygous youngsters (GH LV) differed in a large format of the exterior compared to homozygous contemporaries (GH VV). The significant superiority was established absolutely for all studied measurements. The maximum effect of heredity factor on the variability of live weight was detected at the age of 18 months-24.81% (P <0.05). The calculation of the organized factor impact to the overall variability of linear growth in heifers of different allelic variants for the GH gene showed significance (P <0.05) at 18 months of age. Thus, the detection of single-nucleotide polymorphisms in GH gene can improve the accuracy of the selection in beef herds.
Abstract. The aim of research is to monitor the genetic diversity of Kazakh White-Headed breed, taking into account the GH L127V and GHR F279Y polymorphisms. Research methods. The object of the study were cows (n = 57 heads) and young animals (calves and heifers, n = 50 heads) from the breeding farm “Krasnyy Oktyabr’”, Volgograd region. Whole blood of animals served as the biomaterial; genotyping was carried out according to the polymorphisms GH L127V in growth hormone gene and GHR F279Y in growth hormone receptor gene by PCR-RFLP method. Results. The study of the gene pool by polymorphisms of the somatotropic axis genes in Kazakh White-Headed cattle showed that the representatives of mature herd and young animals had L (PL = 0.660–0.728) and V (PV = 0.272–0.340) alleles in the locus of growth hormone gene, as well as F (PF = 0.412–0.550) and Y (PY = 0.450–0.588) in the locus of growth hormone receptor gene. Genotypes distribution in growth hormone gene polymorphism was more balanced according to the Hardy-Weinberg law, but the population significantly (P < 0.05) deviated from the equilibrium state according to the genetic frequencies in growth hormone receptor gene. Differences in genetic frequencies for the growth hormone gene did not reach a significant level (χ2 = 4.451; P = 0.108) between cows and young animals. Whereas, there were significant differences (χ2 = 12.103; P = 0.002) in the frequencies of homozygous genotypes carriers for the growth hormone receptor gene, which was due to the use of heterozygous sire for this polymorphism in the reproduction of the herd. Scientific novelty. For the first time, data on the assessment of the genetic structure of the Kazakh White-Headed mature herd and replacement young animals of Volgograd selection were obtained according to the polymorphisms GH L127V and GHR F279Y, associated with indicators of meat productivity. The results of the analysis of the genetic structure of the herd indicate the possibility of directed changes in the gene pool of the population in just one generation, which creates the prerequisites for the introduction of marker-assisted selection.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.