Animal Research and One Health最新文献

The aim was to evaluate the ingestive behavior and body development of backgrounded heifers from three genotypes in the Brazilian Pantanal. Twenty-two heifers with an average body weight of 180 kg and 15 months of age were used, distributed into three genotype groups: eight Nelore (N), seven Nelore × Angus (½ Angus, NA), and seven Nelore × Pantaneiro (½ Pantaneiro, NP). Nelore and NP heifers exhibited similar grazing times, which were higher compared with NA heifers. It was observed that chest depth, heart girth, rump width between ischia, and hook width between ilia values were higher in NA heifers and similar among the other genotypes. The total and average daily gain of NA heifers was higher than N and NP heifers. It is concluded that there are significant differences in ingestive behavior and body development among genotypes, suggesting variations in the capacity of genotypes to adapt to the Pantanal environment. These results suggest that the crossbreeding between Nelore and Angus maximizes the benefits derived from heterosis, as individuals from this cross are more efficient in weight gain and have body development with desirable characteristics. The crossbreeding of the Pantaneiro breed with Nelore resulted in low body development in the NP heifers, indicating limited heterosis gains from this cross, even in the breed's native environment.

Fruit and vegetable peels are often regarded as waste, leading to their disposal in landfills. As a result, methane gas emissions during the decomposition of waste lead to the loss of potentially valuable resources. Nonetheless, these peels are an abundant source of nutrients, minerals, and vitamins such as dietary fiber, anthocyanins, ascorbic acid, and phenolic compounds, which can enhance animal health and productivity and, as a result, increase the milk and meat production of livestock as well as the drawing power of draught animals. From an environmental perspective, the utilization of peels for animal feed can significantly reduce organic waste accumulation, decrease greenhouse gas emissions associated with waste decomposition, and lower the dependency on conventional feed ingredients such as grains, which are often produced through resource-intensive agricultural practices. To date, no comprehensive review has been found on the nutritional and environmental impact of fruit and vegetable peels as animal feed. This paper aims to explore the nutritional and environmental impact of various kinds of fruit and vegetable peels.

Brucellosis is a zoonotic disease caused by Brucella spp. which seriously jeopardizes the health and safety of animals and human beings. Therefore, developing a live attenuated vaccine is a priority. In this study, a genetically stable Brucella rough RA343 strain was obtained by cross-induction. The virulence and protective efficacy of RA343 were subsequently assessed, and RA343 showed reduction of survival ability in RAW264.7 cells and low pathogenicity in the murine model in vivo. Immunization with RA343 elevated expression levels of IFN-γ and TNF-α and a robust T-cell immune response in mice. Guinea pigs were inoculated with RA343 at 1 × 10⁹ CFU for single and booster immunization. After the single immunization of RA343, about 60% of guinea pigs could resist the attack of M28 or 2308 strain. The secondary immunization in guinea pigs confer 80% and 70% protection against M28 or 2308 challenges, respectively. Then, the gene expression profile of RAW264.7 cells infected with Brucella abortus A19 or RA343 was analyzed by RNA-seq to investigate the cellular responses immediately after Brucella entry. The RNA-seq analysis revealed that a total of 14,549 genes were significantly regulated by Brucella 1 h postinfection. The differential gene expression was predominantly associated with innate immune responses and many inflammatory pathways, such as MAPK, JAK-STAT, and NF-κB signaling ones. Our findings suggest that the RA343 strain is a promising novel vaccine candidate to protect animals from B. abortus and Brucella melitensis infection. Meanwhile, this study serves as a new reference for investigating the immune regulatory mechanisms of rough Brucella.

RNA-based biopesticides, heralding the third revolution in agricultural pest and disease control, emerge as pivotal for sustainable aquaculture in China. This review delves into the background, evolution, and applications of RNA biopesticides, emphasizing their transformative impact on aquaculture disease management. RNA-based biopesticides offer myriad advantages. Utilizing dsRNA formulations ensures species-specific targeting, thereby minimizing effects on nontarget organisms. Swift environmental degradation of dsRNA addresses concerns about residual effects and pollution. Crucially, the host’s genetic structure remains unchanged, averting heritable variations. Additionally, resistance challenges are easily mitigated through targeted gene replacement. Nevertheless, challenges impede the technology’s full potential. Factors such as target gene selection, varying effectiveness across pests, and susceptibility of dsRNA to pathogen degradation can influence overall efficacy. The widespread use of RNA pesticides prompts scrutiny of their impact on nontarget organisms’ immune systems, necessitating meticulous consideration of exogenous dsRNA biosafety. Furthermore, assessing the toxicity of viruses and microorganisms as dsRNA carriers is crucial. High production costs and lower efficiency in large-scale production compared to conventional pesticides demand urgent attention. Future research should prioritize the optimization of dsRNA delivery systems to improve stability and targeting precision. Investigating the integration of RNA-based pesticides with other sustainable agricultural practices may further mitigate environmental impacts. Moreover, advancements in cost-effective production techniques and regulatory frameworks will be critical for enabling the widespread adoption of RNA biopesticides, thereby securing their role in the future management of global aquaculture diseases.

Meiotic recombination is key for genetic diversity, but its dynamics are underexplored in small inbred beef cattle populations. This study examines recombination in closed beef cattle populations and identifies related genomic regions. Using genotypic data from 1020 Line 1 Hereford and 3420 Composite Gene Combination (CGC) cattle, recombination rates were estimated through offspring and progenitor haplotypes. The CGC composite displayed a higher recombination rate (27.24 events) than the Line 1 population (26.38 events), with reduced rates in Line 1 potentially due to extended homozygous segments. Recombination varied by autosome length, increasing with longer autosomes. A genome-wide association study revealed novel genomic regions associated with recombination: significantly associated SNP markers were found on Bos taurus autosome (BTA) 1, 7, 13, 15, and 19 in the Line 1 population, and numerous others in the CGC population, indicating complex polygenic influences.

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.

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.