The effects of the feeding duration of propylene glycol on major meat quality parameters and substantial proteins in the muscle of Akkaraman lambs.

In this study, the effects of propylene glycol (PG) on meat quality and molecular pathways related to energy metabolism in longissimus lumborum muscle on lambs were evaluated. Seventy-two lambs were divided into three groups consisting of 60th, 90th, and 120th of slaughter days. The dosage of the PG and slaughter days were the variables used in the study. Eight animals were slaughtered from each group on each day. The meat quality parameters (e.g., pH, protein, fatty acid profile) and IGF-1, IGFBP4, and DGAT1 (i.e., mRNA and protein levels) were evaluated. The pH 45 min post-slaughter was higher in PG groups on 120th day. On the 4th day after slaughter, the b value was the lowest in the PG3, while 7th day after slaughter it was highest in Con and PG3 on 90th day. The total n3 and n6 were lowest and the NV was highest on 120th day. The IGFBP4 was upregulated in the PG groups on all of the slaughter days. The DGAT1 was upregulated in the PG3 on the 90th day. The IGF-1, DGAT1, IGFBP4 protein levels were found to have increased in the PG3 on 90th day. The IGFBP4 was found to have decreased in the PG3 on 120th day. According to the results of the study, the oral administration of the PG at the 3 mL/kg live weight0.75 for at least 120 days may have positive effects on meat quality in lambs through the IGF-1, DGAT1, and IGFBP4 genes and the proteins encoded by these genes.

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.

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.

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.

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.