Effects of the Oat Hay Feeding Method and Compound Probiotic Supplementation on the Growth, Antioxidant Capacity, Immunity, and Rumen Bacteria Community of Dairy Calves.

This study aimed to investigate the effects of the oat hay feeding method and compound probiotics (CMP) on the growth, health, serum antioxidant and immune indicators, rumen fermentation, and bacteria community of dairy calves from 3 to 5 months of age. Forty-eight female Holstein calves (80 ± 7 days of age, 93.71 ± 5.33 kg BW) were selected and randomly divided into four groups. A 2 × 2 factorial design was adopted for the experiment, with the factors of the oat hay feeding method (fed as free-choice or 16.7% in the diet) and compound probiotics (CMP) inclusion (0.15% or 0%) in the pelleted starter. The results showed that, compared with giving oat hay as free-choice, feeding a diet of 16.7% oat hay increased the pelleted starter intake at 1-84 d (p < 0.05), with an average daily gain (ADG) at 61-84 d (p = 0.02); adding CMP to the pelleted starter did not significantly affect body weight, and reduced the fecal index (p < 0.05). Feeding 16.7% oat hay increased the concentration of IgA, IgG, and IgM (p < 0.01), while adding CMP increased the catalase (p < 0.01) and decreased the concentration of malondialdehyde (p < 0.01) in serum. Feeding 16.7% oat hay increased the ruminal concentration of propionic acid (p < 0.05) and isobutyric acid (p = 0.08), and decreased the ruminal pH (p = 0.08), the concentration of acetic acid (p < 0.05), and the ratio of acetic acid to propionic acid (p < 0.01). Feeding 16.7% oat hay reduced the relative abundance of ruminal Firmicutes, Unidentified-Bacteria, Actinobacteria, Prevotella, NK4A214-group, Olsenella, and Actinobacteriota (p < 0.05); adding CMP increased the relative abundance of ruminal Prevotella, Rikenellaceae-RC9-gut-group, Ruminococcus, NK4A214-group, and Ruminococcus (p < 0.05), and decreased the abundance of Desulfobacterora, Prevotella-7, and Erysipelotricaceae-UCG-002 (p < 0.05). In conclusion, feeding a diet of 16.7% oat hay increased the pelleted starter intake and average daily gain, while slightly reducing the ruminal pH values; adding CMP to the pelleted starter resulted in reduced diarrhea incidence, increased serum antioxidant capacity and immunity, as well as ruminal richness and diversity of microorganisms in dairy calves from 3 to 5 months of age.

Dealing With Stress in Cats: What Is New About the Olfactory Strategy?

Domestic cats are descended from solitary wild species and rely heavily on the olfaction system and chemical signals for daily activities. Cats kept as companion animals may experience stress due to a lack of predictability in their physical or social environment. The olfactory system is intimately connected to the brain regions controlling stress response, thus providing unique opportunities for olfactory strategies to modify stress and related behavioral problems in cats. However, the olfactory intervention of stress in cats has been mainly focused on several analog chemical signals and studies often provide inconsistent and non-replicable results. Supportive evidence in the literature for the potentially effective olfactory stimuli (e.g., cheek and mammary gland secretions, and plant attractants) in treating stress in cats was reviewed. Limitations with some of the work and critical considerations from studies with natural or negative results were discussed as well. Current findings sometimes constitute weak evidence of a reproducible effect of cat odor therapy for stress. The welfare application of an olfactory stimulus in stress alleviation requires a better understanding of its biological function in cats and the mechanisms at play, which may be achieved in future studies through methodological improvement (e.g., experiment pre-registration and appropriate control setting) and in-depth investigation with modern techniques that integrate multisource data. Contributions from individual and environmental differences should be considered for the stress response of a single cat and its sensitivity to olfactory manipulation. Olfactory strategies customized for specific contexts and individual cats can be more effective in improving the welfare of cats in various stressful conditions.

Gallnut Tannic Acid Exerts Anti-stress Effects on Stress-Induced Inflammatory Response, Dysbiotic Gut Microbiota, and Alterations of Serum Metabolic Profile in Beagle Dogs.

Stress exposure is a potential threat to humans who live or work in extreme environments, often leading to oxidative stress, inflammatory response, intestinal dysbiosis, and metabolic disorders. Gallnut tannic acid (TA), a naturally occurring polyphenolic compound, has become a compelling source due to its favorable anti-diarrheal, anti-oxidative, anti-inflammatory, and anti-microbial activities. Thus, this study aimed to evaluate the anti-stress effects of gallnut TA on the stress-induced inflammatory response, dysbiotic gut microbiota, and alterations of serum metabolic profile using beagle models. A total of 13 beagle dogs were randomly divided into the stress (ST) and ST + TA groups. Dietary supplementation with TA at 2.5 g/kg was individually fed to each dog in the ST + TA group for 14 consecutive days. On day 7, all dogs were transported for 3 h from a stressful environment (days 1-7) to a livable site (days 8-14). In our results, TA relieved environmental stress-induced diarrheal symptoms in dogs and were shown to protect from myocardial injury and help improve immunity by serum biochemistry and hematology analysis. Also, TA inhibited the secretion of serum hormones [cortisol (COR), glucocorticoid (GC), and adrenocorticotropic hormone (ACTH)] and the expression of heat shock protein (HSP) 70 to protect dogs from stress-induced injury, thereby relieving oxidative stress and inflammatory response. Fecal 16S rRNA gene sequencing revealed that TA stimulated the growth of beneficial bacteria (Allobaculum, Dubosiella, Coriobacteriaceae_UCG-002, and Faecalibaculum) and suppressed the growth of pathogenic bacteria (Escherichia-Shigella and Streptococcus), thereby increasing fecal butyrate levels. Serum metabolomics further showed that phytosphingosine, indoleacetic acid, arachidonic acid, and biotin, related to the metabolism of sphingolipid, tryptophan, arachidonic acid, and biotin, respectively, could serve as potential biomarkers of stress exposure. Furthermore, Spearman's correlation analysis showed strong relationships between the four potential serum biomarkers and differential bacteria. Overall, gallnut TA may be a potential prebiotic for the prevention and treatment of stress-induced metabolic disorders by targeting intestinal microbiota.

Effects of a multi-strain probiotic on growth, health, and fecal bacterial flora of neonatal dairy calves.

OBJECTIVE: The aim of this study was to investigate the effects of dietary supplementation with a multi-strain probiotic (MSP) product containing of Bifidobacterium animalis, Lactobacillus casei, Streptococcus faecalis, and Bacillus cerevisiae on growth, health, and fecal bacterial composition of dairy calves during the first month of life. METHODS: Forty Holstein calves (24 female and 16 male) at 2 d of age were grouped by sex and date of birth then randomly assigned to 1 of 4 treatments: milk replacer supplementation with 0 g (0MSP), 2 g (2MSP), 4 g (4MSP), and 6 g (6MSP) MSP per calf per day. RESULTS: Supplementation of MSP did not result in any significant differences in parameters of body measurements of calves during the 30 d period. As the dosage of MSP increased, the average daily gain (p = 0.025) and total dry matter intake (p = 0.020) of calves showed a linear increase. The fecal consistency index of the 2MSP, 4MSP, and 6MSP group calves were lower than that of the 0MSP group calves (p = 0.003). As the dosage of MSP increased, the concentrations of lactate dehydrogenase (p = 0.068) and aspartate aminotransferase (p = 0.081) in serum tended to decrease, whereas the concentration of total cholesterol increased quadratically (p = 0.021). The relative abundance of Dorea in feces was lower (p = 0.011) in the 2MSP, 4MSP, and 6MSP group calves than that in the 0MSP group calves. The relative abundance of Dorea (p = 0.001), Faecalibacterium (p = 0.050), and Mitsuokella (p = 0.030) decreased linearly, whereas the relative abundance of Prevotella tended to increase linearly as the dosage of MSP increased (p = 0.058). CONCLUSION: The MSP product can be used to reduce the diarrhea, improve the performance, and alter the composition of the fecal bacteria in neonatal dairy calves under the commercial conditions.

Characterization of miRNA and their target gene during chicken embryo skeletal muscle development.

MicroRNAs (miRNAs) are non-coding RNAs that regulate mRNA expression by degradation or translational inhibition. We investigated the underlying molecular mechanisms of skeletal muscle development based on differentially expressed genes and miRNAs. We compared mRNA and miRNA from chicken skeletal muscle at embryonic day E11, E16 and one day post-hatch (P1). The interaction networks were constructed, according to target prediction results and integration analysis of up-regulated genes with down regulated miRNAs or down-regulated genes with up-regulated miRNAs with |log2fold change| ≥ 1.75, P < 0.005. The miRNA-mRNA integration analysis showed high number of mRNAs regulated by a few number of miRNAs. In the E11_VS_E16, comparison group we identified biological processes including muscle maintenance, myoblast proliferation and muscle thin filament formation. The E11_VS_P1 group comparison included negative regulation of axon extension, sarcomere organization, and cell redox homeostasis and kinase inhibitor activity. The E16_VS_P1 comparison group contained genes for the negative regulation of anti-apoptosis and axon extension as well as glomerular basement membrane development. Functional in vitro assays indicated that over expression of miR-222a and miR-126-5p in DF-1 cells significantly reduced the mRNA levels of the target genes CPEB3 and FGFR3, respectively. These integrated analyses provide several candidates for future studies concerning miRNAs-target function on regulation of embryonic muscle development and growth.

Low levels of TGF-ß1 enhance human umbilical cord-derived mesenchymal stem cell fibronectin production and extend survival time in a rat model of lipopolysaccharide-induced acute lung injury.

Mesenchymal stem cells (MSCs) are an attractive cellular source for cell­based therapy, tissue engineering and regenerative medicine. However, the use of MSCs is limited by their low incorporation rate in the graft environment. The majority of cells are lost from the graft within 1 month, due to reduced microenvironment or local inflammation at the graft site. The extracellular matrix (ECM) may assist the survival and expansion of MSCs. The present study aimed to identify an effective approach to increase ECM expression levels by MSCs in order to enhance the therapeutic effect and survival rate of MSCs at the injury site. The concentration­dependent effect of transforming growth factor (TGF)­ß1 on human umbilical cord (hUC)­MSC proliferation and expression of ECM genes was investigated. MSCs were successfully isolated, cultured and expanded from hUC. A low concentration of TGF­ß1 (0.1 ng/ml) exhibited the optimal effect on hUC­MSC proliferation and markedly stimulated the expression of ECM genes, particularly fibronectin (FN). Furthermore, treatment with TGF­ß1 caused no alteration in the immunophenotype and differentiation capacity of MSCs. In vivo experiments in rats demonstrated that intravenous injection of control UC-MSCs or TGF-ß1-pre-treated UC-MSCs reduced the severity of lipopolysaccharide-induced lung injury, assessed using histology, measurements of the wet­dry lung weight ratio, and neutrophil count and protein concentration in bronchoalveolar lavage fluid. However, the short­term (48 h) therapeutic effects of untreated and TGF­ß1­pre­treated UC­MSCs were similar. The survival of MSCs in damaged lungs, determined by Sry gene expression levels, were significantly increased in MSCs pre­treated with TGF­ß1. In conclusion, pre­treatment of MSCs with a low concentration of TGF­ß1 enhanced the expression of ECM components, particularly FN, thus, improving the survival and potential therapeutic benefits of MSCs. Pre­treatment of MSCs with TGF­ß1 may prolong the effective therapy time and represent an efficient therapeutic approach for tissue repair.

Chemical composition and antibacterial activity of the essential oil from Pyrrosia tonkinensis (Giesenhagen) Ching.

The present study aimed to analyse the chemical components of the essential oil from Pyrrosia tonkinensis by GC-MS and evaluate the in vitro antibacterial activity. Twenty-eight compounds, representing 88.1% of the total essential oil, were identified and the major volatile components were trans-2-hexenal (22.1%), followed by nonanal (12.8%), limonene (9.6%), phytol (8.4%), 1-hexanol (3.8%), 2-furancarboxaldehyde (3.5%) and heptanal (3.1%). The antibacterial assays showed that the essential oil of P. tonkinensis had good antibacterial activities against all the tested microorganisms. This paper first reported the chemical composition and antimicrobial activity of the essential oil from P. tonkinensis.

Acute nicotine treatment attenuates lipopolysaccharide-induced cognitive dysfunction by increasing BDNF expression and inhibiting neuroinflammation in the rat hippocampus.

Although nicotine has been shown to improve cognitive function in various studies, the mechanisms underlying acute nicotine treatment-induced neuroprotection remain incompletely understood. In this study, we evaluated the effect of acute nicotine treatment on the cognitive impairment induced by lipopolysaccharide (LPS) and explored the underlying mechanism. We found that acute nicotine injection markedly attenuated LPS-elicited cognitive deficits and suppressed the strong LPS-induced release of IL-1ß, IL-6, and TNF-α into serum and the dorsal hippocampus at 4 and 24h after LPS injection. Western blot analysis indicated a clear increase in the levels of cleaved caspase-3 in LPS-treated animals but not in nicotine- or saline-treated animals. Furthermore, nicotine administration led to a significant increase in BDNF mRNA expression at 4 and 24h and in BDNF protein expression at 24h after LPS injection in the dorsal hippocampus. Taken together, acute nicotine administration attenuated LPS-induced cognitive dysfunction, and this neuroprotective effect may be related to the up-regulation of BDNF and the inhibition of neuroinflammation and apoptosis-related proteins in the dorsal hippocampus.

[Analysis on molecular evolution of MC1R gene in dog].

Melanocortin 1 receptor (MC1R) gene regulates pigment synthesis in mammals, and therefore is regarded as an important candidate gene for dog coat color. Based on MC1R amino acids and cDNA sequences of 10 vertebrate animals released by NCBI, molecular evolution of dog MC1R gene was analyzed with bioinformatic software and internet resource. Results showed that 10 vertebrate animals were divided into two major groups, a compact group A (7 mammals) and an incompact group B (chicken, zebrafish and fugu). This phylogenetic tree was consistent with putative evolutionary relationship within these 10 species. Positive selection was detected during the evolutionary process of dog (also cat and pig) from cattle by PAML branch model (omega = 90.8177), and five amino acids of 2V, 25E, 184N, 197V and 314L of dog MC1R were predicted under positive selection by site model. Comparative linkage analysis of chromosome showed that "ZFP276-MC1R-GAS8" linkage group was conservative in human, chimpanzee, chicken and dog.