Bovine skin fibroblasts mediated immune responses to defend against bovine Acinetobacter baumannii infection

Inclusion of yeast and saccharides based-product to replace monensin in the diet of confined steers: performance, rumen environment, metabolism, animal health, and meat quality

The present study aimed to evaluate a blend of yeast and saccharides based-product fed via diet to feedlot cattle on performance, health, meat quality, and rumen metabolism when compared to monensin. Twenty-four non-castrated crossbred male steers (Charolais x Nellore) were divided into control (n = 12), receiving the basal diet with monensin (215 mg/animal/day) and treatment (n = 12) receiving the basal diet with the blend of yeast and saccharides based-product (17.2 g/animal/day). Animals were weighed on days 1, 20, and 113, and on days 20, 70, and 113, blood and rumen fluid were collected, which was also used to determine the genera of bacteria present in the rumen and to quantify protozoa. Total feces were collected to determine apparent total tract digestibility from days 108 to 112 of the experiment. There was no treatment effect for weight gain, feed intake, or feed efficiency. There was a gain in the loin eye area in the control group (P = 0.05) and greater subcutaneous fat thickness in the loin and rump cap control group (P = 0.01). In the ruminal fluid, there was higher protozoa count in the treatment group on day 113 (P = 0.03) and a higher proportion of propionic acid in the treatment group on day 70 (P = 0.03). Total short-chain fatty acids were lower in steers in the treatment group. There was no treatment effect on the ruminal microbiota. There were lower counts of lymphocytes and granulocytes in the blood of steer in the treatment group (P < 0,05). A significant increase in the concentrations of immunoglobin A (IgA) and others heavy-chain immunoglobulins (IgM, IgG, IgM and IgE) were observed in the treatment group. There was an effect of treatment on glutathione S-transferase (GST) activity on days 70 and 113 (P = 0.02). Likewise, high GST activity in the liver was identified in the treatment group (P = 0.01). For fatty acid profile in meat, oleic acid presented higher proportion in the treatment group (P = 0.04), in contrast to docis-5,8,11,14,17-eicosapentaenoic acid, which was lower in the same group (P = 0.05). It is concluded that the blend of yeast and saccharides based-product played a role similar to monensin's in productive performance, demonstrating a potential to substitute monensin. Furthermore, the inclusion of yeast and saccharides in the diet stimulated the humoral immune response and antioxidant action without affecting meat quality.

The Effects of a Blend of Essential Oils in the Milk of Suckling Calves on Performance, Immune and Antioxidant Systems, and Intestinal Microbiota

The objective of the present study was to determine whether the addition of a blend based on the essential oils of cinnamon, oregano, and eucalyptus to the liquid diets of calves would stimulate the immune system combined with anti-inflammatory action, minimize oxidative responses, and alter the intestinal microbiota, consequently enhancing animal growth. Twenty-four male Holstein calves (approximately five days old) were suckled for 60 days, underwent a weaning process, and were followed up until day 75 of the experiment. The calves were divided into control (n = 12) and phytobiotic (n = 12) groups, receiving commercial milk replacer and pelleted concentrate ad libitum. For the phytobiotic group, we added the blend to the liquid diet twice daily at 5 mL/feeding in the first 15 days and 10 mL/feeding until day 60. We detected no differences in weight gain, but animals in the phytobiotic group tended to consume less feed. Calves treated with phytobiotics showed better conversion and feed efficiency than the animals in the control group. Lower leukocyte and lymphocyte counts were observed, as was a higher cholesterol concentration. Immunoglobulin A, ceruloplasmin, and transferrin also differed between groups, with higher IgA and lower levels of acute-phase proteins (ceruloplasmin and transferrin) in calves that consumed the phytobiotic. Higher glutathione S-transferase activity was found in the serum of calves in the treatment group. The intestinal microbiota did not differ between the groups; however, the genera Acinetobacter, Pseudomonas, and Psychrobacter were the most abundant regardless of treatment. We concluded that the blend of oils based on cinnamon, oregano, and eucalyptus improved the calves' immune and antioxidant systems, improving feed efficiency without affecting the intestinal microbiota.

Effects of miR-722 on gene expression and alternative splicing in the liver of half-smooth tongue sole after infection with Vibrio anguillarum

MicroRNAs play crucial roles in various biological processes, including but not limited to differentiation, development, disease, and immunity. However, their immunoregulatory roles in half-smooth tongue sole are lacking. Our previous studies indicated that miR-722 could target C5aR1 to modulate the complement pathway to alleviate inflammatory response and even affect the mortality after the bacterial infection with Vibrio anguillarum. Driven by the purpose of revealing the underlying mechanisms, in this study, we investigated the effects of miR-722 on the gene expression and alternative splicing (AS) in the liver of half-smooth tongue sole after Vibrio anguillarum infection, with the approach of miR-722 overexpression/silencing and subsequent RNA-seq. Among the different comparisons, the I group (miR-722 inhibitor and V. anguillarum) versus blank control (PBS) exhibited the highest number of differentially expressed genes (DEGs), suggesting that the immune response was overactivated after inhibiting the miR-722. In addition, enrichment analyses were performed to reveal the functions of DEGs and differential AS (DAS) genes, reflecting the enrichment of RNA splicing and immune-related pathways including NF-κB and T cell receptor signaling pathway. Comparing the M group (miR-722 mimic and V. anguillarum) with the negative control (random sequence and V. anguillarum), two immune-related genes, cd48 and mapk8, were differentially expressed, of which mapk8 was also differentially spliced, indicating their importance in the immune response. Furthermore, representative gene analysis was performed, suggesting their corresponding functional changes due to AS. To verify the RNA-seq data, quantitative real-time PCR was employed with twenty pairs of primers for DEGs and DAS events. Overall, our results demonstrated that miR-722 could mediate the transcriptome-wide changes of gene expression and AS in half-smooth tongue sole, and provided insights into the regulatory role of miR-722 in immune responses, laying the foundation for further functional analyses and practical applications in aquaculture.

Weighted single-step genome-wide association study and functional enrichment analyses for gastrointestinal nematode resistance traits in Santa Ines sheep

This study aimed to identify genomic regions, pathways, and putative candidate genes associated with resistance to gastrointestinal nematode in Santa Ines sheep. The phenotypic information comprised 5529 records from 1703 naturally infected animals. After genomic data quality control, 37,511 SNPs from 589 animals were available. The weighted single-step approach for genome-wide association study was performed to estimate the SNP effects and variances accounted by 10-SNP sliding windows. Confirming the polygenic nature of the studied traits, 20, 22, 21, and 19 genomic windows that explained more than 0.5% of the additive genetic variance were identified for fecal egg counts (FEC), Famacha© (FAM), packed cell volume (PCV), and total plasma protein (TPP), respectively. A total of 81, 122, 106, and 101 protein-coding genes were found in windows associated with FEC, FAM, PCV, and TPP, respectively. Several protein-coding genes related to the immune system and inflammatory response functions were identified within those genomic regions, such as ADCY9, ADRB2, BRAF, CADM1, CCL20, CD70, CREBBP, FNBP1, HTR4, IL16, IL22, IL26, MAPK8, NDFIP1, NLRC3, PAK5, PLCB1, PLCB4, ROCK1, TEK, TNFRSF12A, and VAV1. Functional enrichment analysis by DAVID tool also revealed many significant (P < 0.05) pathways and Gene Ontology terms that could be related to resistance to gastrointestinal nematode in Santa Ines sheep, such as chemokine signaling pathway (oas04062), cAMP signaling pathway (oas04024), cGMP-PKG signaling pathway (Oas04022), platelet activation (Oas04611), Rap1 signaling pathway (oas04015), and oxidoreductase activity, acting on paired donors, with incorporation or reduction of molecular oxygen (GO:0016705). These results contribute to improving the knowledge of the genetic architecture of resistance to gastrointestinal nematode in Santa Ines sheep.