Veterinary Research Communications最新文献

Piroplasmosis caused by tick-borne piroplasm is a vital zoonotic disease that poses significant concerns for human and animal health. However, the information on the molecular prevalence of the piroplasm transmitted by ticks is limited in Qinghai, China. Here, we investigated the geographic distribution of 544 collected ticks and the genetic diversity of tick-borne piroplasm in four areas of Qinghai. The results of the tick species identification revealed that the obtained ticks were Haemaphysalis qinghaiensis, Dermacentor everestianus, D. silvarum and D. nuttalli. Nested PCR revealed that the overall prevalence of piroplasm was 25% and included Theileria luwenshuni, T. equi, T. uilenbergi, Theileria sp. OT3 and T. ovis. Furthermore, the phylogenetic trees revealed that the piroplasm carried by ticks was individually clustered with piroplasm carried by various ticks in different regions, and the genotype of T. equi was found to be type B. The present study revealed that the distributions of tick species and the piroplasm carried by ticks in some areas of Qinghai Province are high diverse and distinct spatial heterogeneity. Moreover, Theileria sp. OT3 and T. equi were first discovered in ticks distributed in Qinghai Province, indicating that the epidemic risk of piroplasm transmitted by ticks is increasing, providing a theoretical foundation for the prevention and control of tick-borne piroplasmosis in this region.

The present study aimed to assess the effects of chitosan nanocapsules loaded with synthetic carvacrol and thymol (structurally analogous to those in oregano oil) on the antioxidant and molecular response of Litopenaeus vannamei subjected to acute thermal stress. Chitosan nanocapsules (of 246 nm) were prepared and incorporated into shrimp feed at eight concentrations in triplicate: 0.0 (0ChNP), 0.033mg g^- 1 (0.03ChNP), 0.1mg g^- 1 (0.1ChNP), 0.2mg g^- 1 (0.2ChNP), 0.3mg g^- 1 (0.3ChNP), 0.467mg g^- 1 (0.5ChNP), 0.633mg g^- 1 (0.6ChNP), and 0.8mg g^- 1 (0.8ChNP). Twenty-four aquariums, each containing three shrimp (10.25 ± 1.14 g), were fed for two weeks. The first 8 days at 27 ± 0.5 °C, followed by a gradual temperature increase to 39 °C. Thereafter, shrimps were sampled, and the hepatopancreas dissected and divided into two, and individually stored in RNAlater for transcriptomic and qPCR analysis. The groups 0ChNP, 0.03ChNP, and 0.3ChNP were selected for transcriptomic analysis based on their physical appearance, and mortality rate. At 0.03ChNP, significant upregulation of genes associated with innate immunity, vesicular trafficking, and autophagy was detected, suggesting an activated protective response. On the other hand, the qPCR on anti-oxidative enzymes, catalase and glutathione peroxidase, showed lower levels than in the control experiments suggesting reduced oxidative stress when chitosan nanocapsules were supplied, especially with 0.3ChNP. In conclusion, chitosan nanocapsules delivering carvacrol and thymol at 0.3 mg g^- 1 of feed modulate distinct molecular pathways that contribute to thermal stress resilience in shrimp. Doses below or above this threshold were ineffective or detrimental under the conditions tested.

The hybrid groupers (Epinephelus fuscoguttatus female × Epinephelus lanceolatus male) have been seriously harmed by Vibrio harveyi, but the acute damage and the underlying immune defense mechanisms during infection are still unknown. In this study, fish in the treatment group were challenged with 200 µL of V. harveyi suspension (1.01 × 10⁸ CFU/mL) to investigate the mechanisms underlying V. harveyi infection in hybrid grouper by integrating histopathology, biochemistry, and high-resolution transcriptomics. Histopathological analyses revealed that V. harveyi infection induced severe liver apoptosis, as evidenced by TdT-mediated dUTP nick-end labeling assays. Biochemical assays indicated a significant increase in glutamic-pyruvic transaminase (GPT; P < 0.05), while malondialdehyde (MDA) was significantly decreased (P < 0.05). Moreover, transcriptomic profiling revealed significant enrichment in the p53 signaling pathway, alanine, aspartate and glutamate metabolism, and cholesterol metabolism. Quantitative real-time polymerase chain reaction further confirmed the significant upregulation of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and Toll-like receptor 3 (TLR-3). In addition, redundancy analysis revealed the correlations between enzyme activities and differentially expressed genes. Overall, these results demonstrate that V. harveyi infection compromises hepatic health in hybrid grouper by inducing structural damage to the liver, perturbing oxidative stress, and impairing both immune function and metabolic processes.

Antimicrobial resistance (AMR) is a monolithic issue, particularly the global emergence of Methicillin-resistant Staphylococcus aureus (MRSA). This study investigated the prevalence of MRSA, its association with resistant genes and virulence factors. Furthermore, phylogenetic analysis, antibiogram, and In-silico analysis were performed. For this, 1,132 subclinical mastitis-positive milk samples from livestock (cattle, buffalo, sheep, goat, camel) were collected using convenient sampling. Out of the total, 558 (49.29%) and 441 (38.96%) isolates were found to be positive for S. aureus based on phenotypic and genotypic information, respectively. Moreover, the highest MRSA prevalence was found in cattle 56 (53.33%), while the lowest was in buffalo 21 (18.75%), using the PCR tool. Also, the prevalence of enterotoxin and biofilm-producing icaA and icaD genes was evaluated. Antibiogram of MRSA isolates revealed that dairy animals exhibited high resistance to penicillin G, cefoxitin, and gentamicin, but remained susceptible to ciprofloxacin and moxifloxacin. MRSA of sheep origin showed distinct resistance patterns, showing more sensitivity towards gentamicin and amoxicillin. Also, out of 159 MRSA isolates, 111 were declared as MDR S. aureus. Phylogenetic analysis revealed that Pakistan MRSA isolates were closely related to each other, with goat and buffalo MRSA isolates showing a close evolutionary relationship. In-silico analysis showed that all dairy animals in Pakistan shared conserved nucleotide and amino acid motifs. This study concludes that MRSA represents a serious threat to livestock health due to its multidrug-resistant properties, and antibiogram profiling can provide a valuable tool for guiding effective therapeutic interventions against MRSA infections.