Animal Research and One Health最新文献

Enterococcus faecalis is known for its ability to form strong biofilms and its role as an opportunistic pathogen. In this study, we screened and characterized a multidrug-resistant (MDR) and strong biofilm-forming E. faecalis isolate obtained from a shrimp sample to determine its genetic diversity, molecular epidemiology, and underlying factors associated with antimicrobial resistance genes (ARGs) and virulence factor genes (VFGs). The E. faecalis MTR_EFS01 strain was isolated using culturing, staining, and biochemical tests and MALDI-TOF methods. The MDR profile of the strain was determined through the disk diffusion test. The complete genomic sequence of E. faecalis MTR_EFS01 was obtained using the Illumina NextSeq2000 platform. The de novo assembly of the E. faecalis MTR_EFS01 genome revealed a total length of 2,862,301 bp with 80.0 × coverage. This genome comprised 38 contigs, a G + C content of 37.4%, and identified two CRISPR arrays, seven prophages, and 55 RNA genes. The E. faecalis MTR_EFS01 strain was classified as ST862 with a high pathogenicity index of 0.896. The strain harbored eight ARGs conferring resistance to tetracycline, erythromycin, trimethoprim, and MDR efflux pumps. Furthermore, 27 VFGs were identified in this strain, linked to antiphagocytosis, adherence, biofilm formation, enzymes, and immune invasion. Metabolic functional analysis revealed that our strain had 243 subsystems, with the most abundant genes associated with carbohydrate metabolism, amino acids and derivatives, and protein metabolism. The findings in this study underscore the importance of continuous monitoring, research, and collaborative efforts to address the growing threat of MDR and biofilm-forming pathogens in diverse settings.

Aeromonas hydrophila infection is one of the key factors limiting tilapia production, and antibiotics play important roles in the control of diseases. This study evaluated the effectiveness of florfenicol (FFC) when administered orally at the therapeutic dose of 15 mg/kg fish biomass/day for 10 days against A. hydrophila infection in Oreochromis niloticus in terms of survival, changes in haemato-biochemistry, erythrocyte morphology, and histoarchitecture of the vital organs. A. hydrophila was moderately virulent to tilapia with an LD₅₀ of 1.15 × 10⁷ cells/fish. When challenged, it caused systemic infection in fish. The challenged fish were lethargic, wandered around the corners, rested at the bottom, swam vertically, and darkly pigmented. The FFC therapy effectively reduced bacteria-induced mortalities and physiological stress as the measured haemato-biochemical parameters indicated. The histopathological findings suggested alterations in tissue architecture of the kidney and liver tissues, which improved in the treated fish. Erythrocytes of the challenged fish showed elongated, irregular-shaped, tear-drop-shaped, crenated, and hypochromic erythrocytes, ragged cytoplasmic membranes, vacuolation, hypertrophied nucleus, and eccentric nucleus. These morphological alterations were reduced with FFC therapy. Compared to the untreated group, the FFC treatment normalized the haemato-biochemical parameters, improved wound healing, and promoted fish recovery against bacterial infections. The results hinted at the effectiveness of FFC against A. hydrophila infection in O. niloticus juveniles at the therapeutic dose. However, care must be taken for its judicious aquacultural application to avoid its negative impacts on fish, the environment, and consumers.

Understanding differences in chromatin state and changes in gene regulatory landscape of placode (Pc) and dermal condensate are crucial for decoding hair follicle (HF) morphogenesis programs. To identify cell-type-specific chromatin accessibility patterns in the developing HF, we integrated chromatin accessibility and transcriptome profiles at single-cell resolution during the murine HF induction stage. We applied unbiased analyses to identify seven major HF cell types and reclustered dermal (Der) and epithelium (Epi) subtypes to trace their cell fate specification. Our analysis showed that gene regulation in Der and Epi lineages is largely determined by cis-regulatory elements that direct gene expression in response to specific developmental cues. The chromatin accessibility of Twist2, Enpp2, Dkk1, and Sox2 varied from fibroblasts (Fb) to pre-DC lineage, while that of Edar, Lhx2, and Wnt10b varied from Epi to Pc lineage. Cell-type-specific enrichment of transcription factor binding motifs implicated Twist2 and Nfatc4 as key regulators in Fb to pre-DC fate specification, and Fos, Bach1, and Klf1 in Epi to Pc niche fate specification. Additionally, alignment of cell-type-specific peaks to super-enhancer databases identified key regulatory elements in both lineages. We identified and validated the critical cis-regulatory elements in pre-DC and Pc fate specifications through embryonic dorsal skin culture in vitro, suggesting that these elements may regulate critical genes essential for HF induction. Overall, our results provide a foundation for a comprehensive analysis of gene regulatory programs that initiate HF development, offering insights into the molecular mechanism of HF morphogenesis and clinical treatments of alopecia by skin grafts.

Dietary selenium (Se) deficiency is recognized as a global problem, and exogenous Se supplementation can effectively enrich its levels in animal bodies. Offal tissues are equally important as meat in Se enrichment. Varying properties among Se species require information beyond total Se concentration to fully evaluate health risk/benefits. In the present study, the reliable inductively coupled plasma mass spectrometry (ICP-MS) and HPLC-ICP-MS methods were optimized to analyze total Se content and Se speciation in the muscle and kidney of sheep, kidney and liver of pig, and liver of chicken after different Se supplementation treatments. The total Se contents in the liver and kidney were higher than in muscle. Five Se species were detected in the muscle, and selenourea was additionally detected in the liver and kidney. Sheep muscle and chicken liver mainly contained selenomethionine, and other tissues mainly contained selenocysteine. As the levels of selenomethionine or selenium-enriched yeast increased in the feed, the proportion of selenomethionine in the sample increased, as well as the proportion of selenocysteine decreased, and almost no inorganic selenium was detected in all tissues. This study has provided insights for analyzing the Se enrichment patterns in tissues, which is significant for understanding the Se metabolism, animal health, and enriching the dietary Se supplementation for humans.

Tribbles pseudokinase 3 (TRIB3) interacts with a variety of proteins and plays a key role in the regulation of glucose metabolism and glycolysis in nonruminants, but whether it has a specific role in goat mammary lipid metabolism has still been kept unknown. In this study, we observed that TRIB3 is highly expressed in the mammary tissues of lactating dairy goats. Overexpressing TRIB3 in goat mammary epithelial cells (GMECs) suppressed the mRNA expression of GPAM, DGAT1, and PLIN1, which are associated with the formation of triacylglycerol and lipid droplets (p < 0.05). The fatty acid-sensitive transcription regulator PPARG was also downregulated. Interfering TRIB3 had the opposite effect and decreased Akt phosphorylation. The TRIB3 gene influenced fatty acid composition in GMECs, and its overexpression reduced the total concentration of intracellular triacylglycerol (p < 0.01), this response was verified using BODIPY staining. Overall, these data indicated that TRIB3 suppresses milk fatty acids metabolism through inhibiting p-AKT/PPARG signaling in GMECs.

The intestinal tract is the main place for animals to digest food and absorb nutrients, which also serves as the first line of defense against pathogens that invade the internal environment. Therefore, normal intestinal structure and function are essential for animal health. Poultry coccidiosis is an intestinal disease primarily caused by the parasitization of intestinal epithelial cells by protozoa of the genus Eimeria. The occurrence of coccidiosis not only compromises the intestinal integrity of poultry but also increases their disease susceptibility, thus posing a serious threat to the overall health and productivity of poultry. Nowadays, the primary methods for controlling and preventing coccidiosis in poultry are anticoccidial drugs or live oocyst vaccines. However, the use of the former may be associated with problems of resistance and drug residues, while the use of the latter may cause intestinal damage and significantly increase farming costs. For these reasons, it is critical to investigate green, safe, and cost-effective natural alternative strategies such as phytochemicals and probiotics for controlling coccidiosis as well as mitigating the deleterious effects of coccidial infections in production. In this review, we aim to summarize the role, mechanisms, and therapeutic potential of natural products in the treatment of coccidiosis to lay a theoretical foundation for effective coccidiosis control.

This review provides an in-depth analysis of vitamin E's multifaceted role in swine nutrition, incorporating both traditional insights and contemporary research. It begins with an exploration of vitamin E from an evolutionary perspective, followed by a detailed examination of its absorption, metabolism, and excretion in swine. The review emphasizes the micronutrient's critical functions in swine physiology, particularly its antioxidant properties and its emerging links to epigenetics, which include deoxyribonucleic acid methylation, histone modification, and noncoding ribonucleic acid regulation. The interactions of vitamin E with other dietary components are discussed, along with established nutritional requirements and current recommendations for supplementation. Additionally, the health benefits and performance improvements associated with vitamin E are presented, emphasizing its importance in immune function, growth, and meat quality. Despite extensive research, the review identifies gaps in understanding the bioavailability and long-term impacts of different vitamin E isoforms and supra-nutritional supplementation levels. It concludes with a discussion of research gaps and future directions, particularly the need for studies on the long-term effects of high-dose vitamin E supplementation and the influence of environmental factors on its metabolism. Through this comprehensive synthesis, this study aims to provide a holistic understanding of vitamin E's essential contributions to swine health and nutrition, with the goal of informing better dietary practices and enhancing swine productivity.

This study aimed to evaluate the effects of a terracotta drinker and/or water supplementation with ASPRO-C Plus on the zootechnical performance of broiler chickens reared in a hot environment. A total of 160 Cobb 500 broiler chicks of 15 days old (240.2 ± 39.82 g) were divided into four treatment groups in a 2 x 2 factorial arrangement of drinker type (plastic or terracotta) and water with or without ASPRO-C Plus (1 g/L) supplementation, each consisting of 4 replicate pens. Respiratory rate, water intake, feed intake, and live body weight were recorded weekly. At 49 days old, 12 birds per group were randomly selected, fasted for 12 h, weighed, and slaughtered for carcass evaluation and blood collection. The respiration rate of broilers decreased significantly (p < 0.01) with the terracotta drinker as compared to the plastic drinker. The water intake, the feed intake and the body weight gain increased significantly (p < 0.01) with the terracotta drinker as compared to the plastic drinker. The water addition of ASPRO-C Plus significantly increased (p < 0.01) the relative weight of abdominal fat and spleen in broilers. The alpha-amylase activity was significantly decreased (p < 0.01) with the water addition of ASPRO-C Plus. The serum content of total cholesterol was significantly increased (p < 0.01) with the terracotta drinker. It can be concluded that ASPRO-C Plus can slightly improve liveability, but using the terracotta drinker can be more efficient in reducing the behavioral response to heat stress and can improve the growth performance.

The circadian clock significantly impacts animal health and productivity, with light playing a crucial role in regulating circadian rhythms. However, the mechanisms behind light-induced circadian transmission remain unclear, particularly in light-sensitive avian species. The pineal gland is a key component acting as the photosensitive master oscillator in the avian clock system. Using transcriptome sequencing and small RNA sequencing technologies, we identified circadian genes and miRNAs in the chick pineal gland under light–dark and sudden constant-light conditions. We observed rhythmic oscillations in up to 1299 genes during the light–dark cycle, with 400 genes maintaining rhythms under constant light. Our findings highlight the light-sensitive temporal organization in birds as the phase distribution of circadian genes in the pineal gland correlates with light exposure changes. A novel regulatory mechanism involving light, cyclic adenosine monophosphate, cyclic guanosine monophosphate, light-sensitive miRNAs, such as gga-miR-34b-5p, and light-sensitive circadian genes, such as CRY2, was discovered to participate in the light input system of the chick pineal clock, through which light regulates the oscillators and outputs of the circadian clock system. Additionally, transcriptomic analysis, liquid chromatography–mass spectrometry, and Oil Red O staining revealed cyclic changes in lipid synthesis and metabolism throughout the circadian day, which may be a key mechanism through which the circadian clock influences pineal physiology. Our results enhance the understanding of light-induced circadian transmission mechanisms and identify potential targets for optimizing the circadian clock through light.