Genetic variations in the leptin gene associated with growth and carcass traits in Nellore cattle

Polymorphism of leptin gene (single nucleotide polymorphisms c.73T>C) and its association with body weight and body measurements in Madura cattle

Background and Aim:

Madura cattle is local cattle in Indonesia. This cattle hasphenotypic variations in growth traits. This study aimed to identify leptin (LEP) gene polymorphism exon 2 associated with body measurements in Madura cattle.

Materials and Methods:

We recorded body weight (BW) and body measurements of 51 Madura cattle aged 1-4 years in Waru District, Madura. The LEP gene genotyping was conducted using the polymerase chain reaction-restricted fragment length polymorphism method with AciI restriction enzyme.

Results:

A 267 bp DNA fragment of the LEP gene was successfully amplified using a pair of primers. This study revealed three genotypes (TT, TC, and CC) and two alleles (T and C). The frequencies of TT, TC, and CC genotypes were 0.275, 0.45, and 0.275, respectively, whereas the frequencies of T and C alleles were 0.500 and 0.500, respectively. The c.73T>C mutation was significantly associated with BW, body length (BL), and chest girth (CG) (p<0.05). Among all genotypes, the TC had the highest BW, BL, and CG.

Conclusion:

Conclusively, LEP gene polymorphism (c.73T>C) exon 2 was polymorphic and associated with body measurements, especially BW, BL, and CG.

MOET Efficiency in a Spanish Herd of Japanese Black Heifers and Analysis of Environmental and Metabolic Determinants

Multiple ovulation and embryo transfer (MOET) systems have been intensively implemented in Japanese Black cattle in Japan and to create Japanese Black herds out of these areas. Environmental conditions influence MOET efficiency. Thus, we describe results of 137 in vivo, non-surgical embryo flushings performed between 2016-2020, in a full-blood Japanese Black herd kept in Spain and the possible effects of heat, year, bull, donor genetic value, and metabolic condition. Additionally, 687 embryo transfers were studied for conception rate (CR) and recipient related factors. A total of 71.3% of viable embryos (724/1015) were obtained (5.3 ± 4.34/flushing). Donor metabolites did not affect embryo production (p > 0.1), although metabolite differences were observed over the years, and by flushing order, probably related to the donor age. CR was not affected by embryo type (fresh vs. frozen), recipient breed, and whether suckling or not suckling (p > 0.1). CR decreased significantly with heat (44.3 vs. 49.2%; (p = 0.042)) and numerically increased with recipient parity and ET-number. Pregnant recipients showed significantly higher levels of cholesterol-related metabolites, glucose, and urea (p < 0.05). Therefore, adequate MOET efficiency can be achieved under these conditions, and heat stress should be strongly avoided during Japanese Black embryo transfers. Moreover, recipients' metabolites are important to achieve pregnancy, being probably related to better nutrient availability during pregnancy.

Random-effect meta-analysis of genetic parameter estimates for carcass and meat quality traits in beef cattle

Considerable variability of genetic parameter estimates is observed among different studies for the same trait, which is associated with the distinct effects included in the statistical model, population breed, and sample sizes. The random-effect meta-analysis summarizes genetic parameters considering the heterogeneity among studies. Therefore, the aim of this study was to perform a random-effect meta-analysis of heritability and genetic correlation estimates for carcass and meat quality traits in beef cattle. A total of 152 estimates of heritability and 83 genetic correlations for longissimus muscle area (LMA), back fat thickness (BFT), and marbling score (MRB) were used. High heterogeneity among published studies was observed for all traits, indicating the need of a random-effects model to perform the analysis. Estimates of heritability through the meta-analysis using the random-effects model were high (0.30 to 0.34), indicating that fast genetic progress can be obtained for these traits. However, genetic correlations had low magnitude (lower than 0.25), which suggested that all three traits should be included in the selection scheme.

Association of leptin gene polymorphism with economic traits in crossbred cattle

The present investigation was carried out to identify two polymorphisms in leptin gene by PCR-RFLP and to examine the possible association of the identified genotypes with growth, production and reproduction traits in 205 female crossbred cattle (½ Holstein Friesian × ½ Hariana). One fragment of 330 bp comprising partial intron 2 and exon 3, and another fragment of 94 bp comprising partial exon 2 of leptin gene were amplified, and digested with HphI and Kpn2I restriction enzymes, respectively, for identification of genotypes. The animals with HphI-RFLPCT and Kpn2I-RFLP-AV genotypes had significantly higher birth weight than the HphI-RFLP-CC and Kpn2IRFLP- AA genotypes respectively. The HphI-RFLP locus had significant effect on body weight at 12 months of age, age at first calving and average daily milk yield, while, Kpn2I-RFLP had significant effect on first lactation milk yield and average daily milk yield. Therefore, leptin gene could be used as a marker for genetic selection of economic traits in cattle.

Insight in Leptin Gene Polymorphism and Impact on Milk Traits in Autochtonous Busha Cattle

Leptin, a biomolecule secreted by adipose tissue, enchances productivity in cattle, especially affecting milk traits. The aim of this study was to detect leptin gene polymorphism on exon 3 (A59V locus) and intron 2 (SAU3AI locus) in the endangered population of autochtonous Busha cattle and associations with milk traits. The study included 46 cows: 36 Busha and 10 half-bred. Milk analyses comprised determination of somatic cell counts, fat, protein, lactose, total solids and solids-not-fat (SNF) concentrations and freezing point depression (FPD). Polymorphisms were determined by PCR-RFLP technique. A single A59V genotype (CC) was affirmed, and two SAU3AI genotypes, AA and AB, with frequencies of 78.26% and 21.74%, respectively. Comparing the obtained results for chemical characteristics of milk between cows with AA and AB, no significant differences were found, except for SNF content and FPD values. Cows with AA genotype had significantly lower (p=0.021) average SNF content (8.74%) in milk compared to the average SNF content (9.28%) in those with genotype AB, while cows with genotype AA (−0.54°C) had significantly higher (p=0.004) average FPD values than those with AB genotype (−0.58°C). The absence of BB genotype and significant differences in the investigated functional traits between two SAU3AI genotypes and the absence of A59V polymorphism (presence of only CC genotype) show that the Busha cattle breed, although being an autochtonous low-producing native breed used for meat and milk production, harbours polymorphism on gentic markers characteristic of high production dairy cows.

Muscle transcriptome signature and gene regulatory network analysis in two divergent lines of a hilly bovine species Mithun (Bos frontalis)

A massive bovine, Bos frontalis, also known as Mithun or Gayal, found at higher altitude is very promising meat and milk animal. For candidate gene and marker discovery, RNA-seq data was generated from longissimus dorsi muscle tissues with Illumina-HiSeq. Such markers can be used in future for genetic gain of traits like feed conversion efficiency (FCE) and average daily gain (ADG). Analysis revealed 297differentially expressed genes (DEGs) having 173 up and 124 down-regulated unigenes. Extensive conservation was found in genic region while comparing with Bos taurus. Analysis revealed 57 pathways having 112 enzymes, 72 transcriptional factors and cofactors, 212 miRNAs regulating 71 DEGs, 25,855 SSRs, mithun-specific 104,822 variants and 7288 indels, gene regulatory network (GRN) having 24 hub-genes and transcriptional factors regulating cell proliferation, immune tolerance and myogenesis. This is first report of muscle transcriptome depicting candidate genes with GRN controlling FCE and ADG. Reported putative molecular markers, candidate genes and hub proteins can be valuable genomic resources for association studies in genetic improvement programme.

Individual and combined effects of <i>CAPN1</i>, <i>CAST</i>, <i>LEP</i> and <i>GHR</i> gene polymorphisms on carcass characteristics and meat quality in Holstein bulls

Abstract. The objective of this study was to determine the association of single nucleotide polymorphisms (SNPs) with carcass characteristics and meat quality traits in selected candidate genes in Holstein bulls. Five SNPs in four genes, i.e. calpain 1 (CAPN1), calpastatin (CAST), leptin (LEP) and growth hormone receptor (GHR), were genotyped in 400 purebred bulls using PCR-RFLP. Statistically significant associations were as follows: CAPN1 G316A with live weight, carcass weight, back fat thickness, m. longissimus thoracis et lumborum area and carcass measurements; CAPN1 V530I with pH and L∗; CAST S20T with live weight, inner chest depth and b∗ value; and GHR with ph, a∗ and h∗. In addition, significant genotypic interactions were observed for dressing percentage (LEP A80V  ×  CAST S20T), pH (CAPN1 V530I  ×  GHR S555G and LEP A80V  ×  GHR S555G) and rump width (CAPN1 V530I  ×  CAST S20T). There was no association between the LEP A80V marker and any of the traits evaluated, nor was there any association of the tested SNPs with chest width, C∗ and marbling score. The present results could therefore be indicative for future studies on meat yield and quality.

Circulating leptin and its muscle gene expression in Nellore cattle with divergent feed efficiency

Background

Leptin has a strong relation to important traits in animal production, such as carcass composition, feed intake, and reproduction. It is mainly produced by adipose cells and acts predominantly in the hypothalamus. In this study, circulating leptin and its gene expression in muscle were evaluated in two groups of young Nellore bulls with divergent feed efficiency. Individual dry matter intake (DMI) and average daily gain (ADG) of 98 Nellore bulls were evaluated in feedlot for 70 d to determinate the residual feed intake (RFI) and select 20 animals for the high feed efficient (LRFI) and 20 for the low feed efficient (HRFI) groups. Blood samples were collected on d 56 and at slaughter (80 d) to determine circulating plasma leptin. Samples of Longissimus dorsi were taken at slaughter for leptin gene expression levels.

Results

DMI and RFI were different between groups and LRFI animals showed less back fat and rump fat thickness, as well as less pelvic and kidney fat weight. Circulating leptin increased over time in all animals. Plasma leptin was greater in LRFI on 56 d and at slaughter (P = 0.0049). Gene expression of leptin were greater in LRFI animals (P = 0.0022) in accordance with the plasma levels. The animals of the LRFI group were leaner, ate less, and had more circulating leptin and its gene expression.

Conclusion

These findings demonstrated that leptin plays its physiological role in young Nellore bulls, probably controlling food intake because feed efficient animals have more leptin and lower residual feed intake.

Effects of polymorphisms at <i>LEP</i>, <i>CAST</i>, <i>CAPN1</i>, <i>GHR</i>, <i>FABP4</i> and <i>DGAT1</i> genes on fattening performance and carcass traits in Simmental bulls

Abstract. The aim of this study was to investigate the effects of single nucleotide polymorphisms (SNPs) at six candidate genes (LEP, CAST, CAPN1, GHR, FABP4 and DGAT1) on fattening performance and carcass traits of Simmental bulls in Turkey. The analysis covered a total of 81 Simmental bulls grown on a private farm that were randomly selected for their fattening period for use in this study. Genotyping was performed using the PCR-RFLP method. The S20T polymorphism at the CAST gene and the G316A polymorphism at the CAPN1 gene were associated with variation in final weight, fattening period, weight gain and average daily gain (P < 0.05). In addition, LEP A80V had a significant effect on hot and chilled carcass weight and dressing percentage (P < 0.05). There was no association between GHR S555G, FABP4 V110M and DGAT1 K232A markers with the traits analysed. These results suggested that focusing on the novel effects of LEP, CAST and CAPN1 gene polymorphisms on meat production traits might be useful for marker-assisted selection in Simmental cattle.

Identification of leptin gene polymorphisms associated with carcass traits and fatty acid composition in Japanese Black cattle

Previous studies have indicated that some leptin gene polymorphisms were associated with economically important traits in cattle breeds. However, polymorphisms in the leptin gene have not been reported thus far in Japanese Black cattle. Here, we aimed to identify the leptin gene polymorphisms which are associated with carcass traits and fatty acid composition in Japanese Black cattle. We sequenced the full-length coding sequence of leptin gene for eight Japanese Black cattle. Sequence comparison revealed eight single nucleotide polymorphisms (SNPs). Three of these were predicted to cause amino acid substitutions: Y7F, R25C and A80V. Then, we genotyped these SNPs in two populations (JB1 with 560 animals and JB2 with 450 animals) and investigated the effects on the traits. Y7F in JB1 and A80V in JB2 were excluded from statistical analysis because the minor allele frequencies were low (< 0.1). Association analysis revealed that Y7F had a significant effect on the dressed carcass weight in JB2; R25C had a significant effect on C18:0 and C14:1 in JB1 and JB2, respectively; and A80V had a significant effect on C16:0, C16:1, C18:1, monounsaturated fatty acid and saturated fatty acid in JB1. The results suggested that these SNPs could be used as an effective marker for the improvement of Japanese Black cattle.

The novel SNPs of leptin gene and their associations with growth traits in Chinese Nanjiang Yellow goat

The leptin (LEP) gene encodes a protein that greatly affects the regulation of body weight, energy balance, and food intake in mammals. The objective of the present work was to identify genetic variants of the caprine LEP gene in 411 individuals from five Chinese goat breeds. Six novel single nucleotide polymorphisms (SNPs) (g.117T > C, g.1642G > A, g.2883G > A, g.3053T > C, g.3190G > A, and g.3314T > C) were detected using DNA sequencing. A chi-squared (χ(2)) test showed that all of the LEP SNPs were in Hardy-Weinberg equilibrium in the studied population (P > 0.05). Six common haplotypes were identified in the five goat populations, with frequencies ranging from 0.083 to 0.244. The r(2) linkage disequilibrium plot of the LEP SNPs indicated linkage disequilibrium only in the cultured breeds (NJ and JY). Statistical analysis revealed that all of the six SNPs of the LEP gene were associated with growth traits. The individuals with the GG genotype at g.1642G>A and g.3190G > A loci showed higher birth weight (2.38 ± 0.03, 2.43 ± 0.05) and weight at 2 months of age (10.59 ± 0.16, 10.71 ± 0.26) than the A-bearing genotypes (AA or GA, P < 0.05). Our findings indicate that polymorphisms of the caprine LEP gene might be important genetic factors influencing growth traits, and these genetic markers may be useful for future marker-assisted selection programs in goat breeding and production.