Genome-wide association study of early liveweight traits in fat-tailed Akkaraman lambs

Small ruminants, especially sheep, are essential for sustainable agricultural production systems, future food/nutrition security, and poverty reduction in developing countries. Within developed countries, the ability of sheep to survive on low-quality forage intake could act as buffer against climate change. Besides sheep's importance in sustainable agricultural production, there has been less ongoing work in terms of sheep genetics in Near East, Middle East and in Africa. For lamb meat production, body weight and average daily gain (ADG) until weaning are critical economic traits that affects the profitability of the industry. The current study aims to identify single nucleotide polymorphisms (SNPs) that are significantly associated with pre-weaning growth traits in fat tail Akkaraman lambs using a genome-wide association study (GWAS). A total of 196 Akkaraman lambs were selected for analysis. After quality control, a total of 31,936 SNPs and 146 lambs were used for subsequent analyses. PLINK 1.9 beta software was used for the analyses. Based on Bonferroni-adjusted p-values, one SNP (rs427117280) on chromosome 2 (OAR2) had significant associations with weaning weight at day 90 and ADG from day 0 to day 90, which jointly explains a 0.8% and 0.9% of total genetic variation respectively. The Ovis aries natriuretic peptide C (NPPC) could be considered as a candidate gene for the defined significant associations. The results of the current study will help to increase understanding of the variation in weaning weight and ADG until weaning of Akkaraman lambs and help enhance selection for lambs with improved weaning weight and ADG. However, further investigations are required for the identification of causal variants within the identified genomic regions.

TLR4, MyD88, and TNF-α Expression in the Lungs of Akkaraman and Romanov Lambs in Response to LPS and LTA

Toll-like receptors are involved in the recognition of bacterial toxins, which cause infection in the respiratory system. This study aimed to evaluate microanatomical and histological alterations in the lungs of 24 healthy Akkaraman and Romanov lambs after the administration of lipoteichoic acid (LTA), lipopolysaccharide (LPS), and LTA + LPS and investigate the gene, protein, and immune expression levels of TLR4, MyD88, and TNF-α molecules, known to have immune functions. Microanatomical examinations showed thickened peribronchial and alveolar walls in the lungs of groups LTA, LPS, and LTA + LPS of both breeds due to immune cell infiltration. TLR4, MyD88, and TNF-α immunoexpressions were positive to varying degrees in the cytoplasm and nucleus of the bronchial and bronchiolar luminal epithelial cells, alveolar epithelial cells, and alveolar macrophages. TLR4 and TNF-α protein expressions were statistically different in the LPS-treated Romanov lambs, compared to the other groups. Among the Akkaraman lambs, TLR4 gene expression was significantly higher in group LPS, and among the Romanov lambs, TLR4, MyD88, and TNF-α gene expressions were significantly higher in group LTA + LPS. Therefore, TLR4, MyD88, and TNF-α molecules, involved in the immune response, were found to be expressed at different levels against LTA and LPS in the lungs of two different sheep breeds.

Effects of propylene glycol used at different doses in Akkaraman lambs rations on metabolism-related parameters and liver gene and protein expression during different feeding periods

This study aimed to investigate the metabolic effects of propylene glycol (PG) over 60, 90, and 120 days in lambs. Seventy-two weaned male lambs were allocated into three groups: control (Con), PG1.5 (1.5 mL/kg live weight0.75 ), and PG3 (3 mL/kg live weight0.75 ). Blood samples were collected at the beginning and slaughter days. Biochemical parameters (glucose, triglycerides, ALT, AST, LDH, BUN, and insulin) and gene and protein levels of peroxisome proliferator activated receptor gamma (PPARγ), diacylglycerol o-acyltransferase 1 (DGAT1), carbohydrate responsive element binding protein (ChREBP), and sterol regulatory element binding transcription factor 1c (SREBP-1c) in the liver were determined. Glucose in PG1.5 was increased on Day 60, while significant differences were observed in biochemical parameters except for insulin on the 60, 90, and 120 days. Biochemical parameters such as ALT, AST, LDH, and BUN increased over time, while triglycerides decreased. DGAT1 gene and protein levels were lower, while SREBP-1c and PPARγ were higher in PG groups on Day 60. While SREBP-1c was lower in PG1.5, ChREBP was higher in PG3 on Day 90. PPARγ, DGAT1, and ChREBP were upregulated in PG3 on Day 120. Positive correlations were found between proteins. The long-term use of PG in lambs did not have detrimental effects on metabolism. The study provides valuable insights into the molecular mechanisms underlying the metabolic effects of PG in lambs, shedding light on its potential applications in lamb production.

LPS- and LTA-Induced Expression of TLR4, MyD88, and TNF-α in Lymph Nodes of the Akkaraman and Romanov Lambs

Toll-like receptor (TLR)-mediated inflammatory processes play a critical role in the innate immune response during the initial interaction between the infecting microorganism and immune cells. This study aimed to investigate the possible microanatomical and histological differences in mandibular and bronchial lymph nodes in Akkaraman and Romanov lambs induced by lipopolysaccharide (LPS) and lipoteichoic acid (LTA) and study the gene, protein, and immunoexpression levels of TLR4, myeloid differentiation factor 88 (MyD88), and tumor necrosis factor-α (TNF-α) that are involved in the immune system. Microanatomical examinations demonstrated more intense lymphocyte infiltration in the bronchial lymph nodes of Akkaraman lambs in the LPS and LTA groups compared to Romanov lambs. TLR4, MyD88, and TNF-α immunoreactivities were more intense in the experimental groups of both breeds. Expression levels of MyD88 and TNF-α genes in the bronchial lymph node of Akkaraman lambs were found to increase statistically significantly in the LTA group. TLR4 gene expression level in the mandibular lymph node was found to be statistically significantly higher in the LTA + LPS group. In conclusion, dynamic changes in the immune cell populations involved in response to antigens such as LTA and LPS in the lymph nodes of both breeds can be associated with the difference in the expression level of the TLR4/MyD88/TNF-α genes.

Investigation of TLR1-9 genes and miR-155 expression in dogs infected with canine distemper

This study aimed to determine the relationship of toll-like receptor (TLR) 1-9 genes and microRNA (miR) -155 expression levels with hematologic parameters in dogs diagnosed with canine distemper. In the study, two groups were used pre-treatment and post-treatment. Infected dogs were diagnosed with canine distemper with the help of a rapid test kit and Real Time-Polymerase Chain Reaction (RT-PCR). Based on the correlation coefficients between the expression levels of the genes examined within the scope of the study and hematologic values, a positive correlation was found between the TLR2 gene and the monocyte (MON) value and between the TLR4 gene and the platelet (PLT) value in the pre-treatment group. A strong positive correlation was identified between TLR3 and TLR9 genes and erythrocyte (RBC) and hemoglobin (HGB) values; between TLR5 gene and RBC, HGB and hematocrit (HCT) values and between TLR9 gene and RBC and HGB values in the post-treatment group, on the other hand, a positive correlation was found between TLR1 gene and MON and neutrophil (GRAN) values; between TLR3 gene and HCT value and between TLR9 gene and MON and HCT values. The study concluded that miR-155 and TLR8 gene were upregulated at a statistically significant level (P < 0.05) Post-treatment in dogs infected with canine distemper and there was a positive correlation between the upregulation of miR-155 and the upregulation of TLR8 in the same period. This result suggests that the upregulated miR-155 expression post-treatment increased TLR8 gene expression. In the light of these findings, it miR-155 may have the potential to be used in clinical practice in the treatment or prognosis of dogs infected with canine distemper.

Effect of LPS and LTA stimulation on the expression of TLR-pathway genes in PBMCs of Akkaraman lambs in vivo

This is the first study investigating the changes in some gene expressions related to the TLR pathway in vivo in sheep. Lipopolysaccharide (LPS) and lipoteichoic acid (LTA) molecules were administrated separately and in combination to the Akkaraman lambs via intranasal route. For this purpose, 28 lambs were distributed into four groups (LPS, LTA, LPS + LTA, and control, n = 7). Blood samples were collected to isolate the peripheral blood mononuclear cells (PBMCs) at 24 h and on day 7. Expression levels of TLR2, TLR4, MyD88, TRAF6, TNF-α, IL-1ß, IL-6, IL-10, NF-κß, and IFN-γ genes were determined by qRT-PCR. Increases were determined in the expression data of TLR2 [LPS (P < 0.05) and LTA + LPS (P < 0.01)], TLR4 [LTA + LPS (P < 0.05)], TNF-α, IL-10 [LTA + LPS (P < 0.05)], and IFN-γ genes in all groups in the mRNA expression analysis of PBMCs isolated at 24 h whereas decreases were determined in the expression levels of these genes on day 7. The combination of LPS + LTA stimulated lamb PBMCs more effectively than separate administration of LPS and LTA at 24 h. Therefore, this article may contribute to the understanding the host-pathogen interaction of respiratory-transmitted bacterial diseases concerning PBMCs at 24 h and on day 7. Also this study may contribute to the dose adjustment for bacterial vaccine studies in sheep. Experimental application doses will be helpful for in vivo and in vitro drug and vaccine development studies in the fields of pharmacology and microbiology.

The EDN2 rs110287192 gene polymorphism is associated with paratuberculosis susceptibility in multibreed cattle population

Paratuberculosis (pTB), also known as Johne's disease (JD), is a contagious, chronic, and granulomatous inflammatory disease of the intestines of ruminants which is caused by Mycobacterium avium subsp. paratuberculosis (MAP) infection, resulting in billions of dollars in economic losses worldwide. Since, currently, no effective cure is available for MAP infection, it is important to explore the genetic variants that affect the host MAP susceptibility. The aim of this study was to analyze a potential association between EDN2 synonymous gene mutations (rs110287192, rs109651404 and rs136707411), that modifies susceptibility to pTB. EDN2 rs110287192, rs109651404 and rs136707411 mutations were genotyped in 68 infected and 753 healthy animals from East Anatolian Red crossbred, Anatolian Black crossbred and Holstein breed cattle by using Custom TaqMan SNP Genotyping Assays. For pTB status, serum antibody levels S/P ≥ 1.0 were assessed in carriers of the different EDN2 genotypes. EDN2 rs110287192 mutation showed a significant association with bovine pTB (adj. p < 0.05). For rs110287192 locus, the odd ratios for GG and TG genotypes versus TT genotypes were 1.73; (95% CI = 0.34–8.59) and 0.53 (95% CI = 0.12–2.37) respectively, which indicated that proportion of TG heterozygotes were significantly higher in control animals as compared to pTB animals. On the other hand, while rs136707411 mutation showed a suggestive association with pTB status in the examined cattle population (nominal p < 0.05); no association was detected between rs109651404 genotypes and pTB status. Selecting animals against rs110287192-GG genotype may decrease the risk of pTB in cattle of the Bos taurus taurus subspecies.

Association of GH, STAT5A, MYF5 gene polymorphisms with milk somatic cell count, EC and pH levels of Holstein dairy cattle

This study was conducted to ivnestigate the associations of GH-AluI, STAT5A-AvaI and MYF5-TaqI gene polymorphisms with milk somatic cell count (SCC), electrical conductivity (EC) and pH levels in Holstein dairy cows. For this purpose, 167 blood and 1670 milk samples of 167 Holstein cows in their 2nd lactation were used. There were significant relationships between GH-AluI genotypes and milk EC (p < 0.001) and between STAT5A-AvaI genotypes and milk EC (p = 0.007), but there were not any significant relationships between MYF5 gene polymorphism and the investigated traits (p > 0.05). The greatest EC values were observed in GH-AluI-LV and STAT5A-AvaI-TT-genotyped individuals. Just because of association of EC with mastitis, it was concluded that present GH-AluI and STAT5A-AvaI polymorphisms could be used in further studies to be conducted to improve mastitis resistance and milk quality traits of Holstein dairy cows.

LEP and SCD polymorphisms are associated with milk somatic cell count, electrical conductivity and pH values in Holstein cows

This study was conducted to determine LEP-Sau3AI, SCD-Fnu4HI, NR1H3-HpyCH4IV and FABP4-HinII gene polymorphisms and to investigate the association between these SNPs and somatic cell count (SCC), electrical conductivity (EC) and pH in Holstein cow milk. LEP-Sau3AI polymorphism found associated with SCC (p < 0.01), EC (p < 0.01) and pH (p < 0.05). LEP-Sau3AI-BB genotype resulted with higher SCC, EC and pH compared to other genotypes. SCD-Fnu4HI polymorphism showed differences in genotypes for EC (p < 0.05) and pH (p ≤ 0.05) traits. While the highest EC value was found in SCD-Fnu4HI-CT genotype, the highest milk pH was found in genotype TT. In addition, NR1H3-HpyCH4IV genotypes was found the only associated with pH (p < 0.05) among all studied phenotypes. Based on the present findings, it was concluded that LEP and SCD genes could be used in breeding programs for improved SCC, EC and pH values in Holstein dairy cows.

Investigation of Growth Hormone Releasing Hormone, Growth Hormone and Prolactin Hormone Gene Polymorphism in Anatolian Water Buffalo

The purpose of this work was to identify GHRH, GH and PRL gene polymorphisms in Anatolian water buffalo by means of the PCR-RFLP method. A total of 126 buffalo were included in this study. PCR amplification gave a 451 bp band for the GHRH gene, a 221 bp band for the GH gene and a 156 bp band for the PRL gene. The PCR products were digested by HaeIII for the GHRH gene, AluI for the GH gene and RsaI for the PRL gene. The GH/AluI and PRL/RsaI polymorphisms were found to be polymorphic, while the GHRH/HaeIII polymorphism was not found in Anatolian water buffalo. The frequencies of GH-L (0.87) and PRL-A (0.55) alleles were found to be high in the examined Anatolian water buffalo. The chi-square test showed that the Anatolian water buffalo were in Hardy-Weinberg (HW) equilibrium for the GH gene while significant deviation was observed from HW equilibrium for the PRL gene. The present study is the first to examine GHRH/HaeIII, GH/AluI and PRL/RsaI polymorphisms in Anatolian water buffalo.

INVESTIGATION OF STAT5A, FSHR AND LHR GENE POLYMORPHISMS IN TURKISH INDIGENOUS CATTLE BREEDS (EAST ANATOLLAN RED, SOUTH ANATOLIAN RED, TURKISH GREY, ANATOLIAN BLACK AND ZAVOT)

The objective of this study was to examine the allelic and genotypic profiles of the Signal Transducer and Activator of Transcription 5A (STAT5A), Follicle Stimulating Hormone Receptors (FSHR), and Luteinizing Hormone Receptor (LHR) genes in five indigenous cattle breeds in Turkey. For this purpose, a total of 329 cattle from East Anatolian Red (EAR), South Anatolian Red (SAR), Turkish Grey (TG), Anatolian Black (AB), and Zavot were genotyped using by PCR-RFLP method. A215 bp fragment of STAT5A, a 306bp fragment of FSHR, and a 303 bp fragment of LHR were amplified and digested with AvaI, AluI, and HhaI restriction enzymes, respectively. In this study two types of alleles C and Tfor STAT5A, C and G for FSHR and C and T for LHR were observed. The highest frequencies for STAT5A-C and STAT5A-T alleles were estimated for the Zavot and TG breeds (0.86) and the EAR breed (0.29), respectively. The highest frequency for FSHR-C and FSHR-G alleles was estimated for the Zavot breed (0.72) and the AB and SARbreeds (0.35), respectively. The highest frequency for LHR-C and LHR-T alleles was estimated for the EAR breed (0.75) and the AB breed (0.39), respectively. According to FT values, a small level of genetic diversity was found among five cattle breeds. The F(ST) value was calculated 0.019 between AB and Zavot. And, the value was significant (p < 0.001), while the other F(ST) values were not significant. According to the genetic distance values (Nei), the highest genetic distance was found between AB and TG while the smallest genetic distance was found between Zavot and TG. The chi-square test showed that the TG and Zavot breeds were in Hardy-Weinberg equilibrium (HWE) for STAT5A gene; the EAR, SAR, TG, and Zavot breeds were in HWE for FSHR gene and the EAR, SAR, and TG breeds were in HWE for LHR gene. In conclusion, further investigation is required to determine the correlation of the FSHR and LHR genes with early puberty for the improvement of sexual precocity, and it is considered that the STAT5A gene may be used to improve the milk yield and milk yield traits of local cattle breeds, including those indigenous to Turkey.

Detection of bovine leukocyte adhesion deficiency (BLAD) in Turkish native and Holstein cattle

The purpose of this work was to study whether the bovine leukocyte adhesion deficiency (BLAD) allele is present in native cattle breeds and the Holstein breed in Turkey. Blood samples were obtained from 120 Holstein, 20 Brown Swiss, 20 Anatolian Black, 20 Turkish Grey, 20 South Anatolian Red and 20 East Anatolian Red cattle. The isolated DNA materials were multiplied in PCR using the primer developed by Kriegesmann et al. (1997). In order to determine the area of mutation in PCR products, the PCR products were digested with TaqI endonuclease enzyme. The resulting fragments were analysed on 2% agarose gel for the absence of a TaqI restriction site. It was found that two of the Holstein cattle (a bull and a cow) were heterozygote BLAD carriers. There was no homozygote BLAD animal. The BLAD allele was not found in the other breeds used in the study. The mutant BLAD allele frequency in the 120 Holstein cattle calculations was 0.0084.