Veterinary Research Communications最新文献

Mastitis in cows is one of the most important diseases that give rise to economic losses in dairy farms. Increasing antimicrobial resistance in Staphylococcus aureus, one of the most common causes of mastitis, is a significant health problem. Due to the problems encountered in treating infections caused by resistant strains, developing alternative treatment methods, such as Nanomaterial systems and natural agents, are important. The essential oil of Melaleuca alternifolia is used as an antibacterial and the primary active component is terpinen-4-ol. This study aimed to investigate the antibacterial and anti-biofilm activity of terpinen-4-ol and terpinen-4-ol loaded polydopamine (T-PDA) nanoparticles against S. aureus isolates, which were resistant to at least one group of antibiotics isolated from milk samples of subclinical mastitis cows. The S. aureus strains were identified by biochemical tests and verified with the API Staph kit. The antibiotic susceptibility of the isolates was determined by the disc diffusion method. The broth microdilution method determined the antimicrobial activities of the terpinen-4-ol and T-PDA nanoparticles, and anti-biofilm activities were assessed using the modified crystal violet method. All of the isolates were resistant to benzylpenicillin and susceptible to trimethoprim/sulfamethoxazole. Multi-antibiotic resistance was detected in the 11 S. aureus isolates used in this study. For the terpinen-4-ol and T-PDA nanoparticles, MIC values were determined in the range of 0.125-0.5% (µL/mL) and 0.125-0.25% (µL/mL), respectively. None of the isolates formed biofilms. As a result, it was found that the antibacterial efficacy of the T- PDA nanoparticles was higher against nine of the S. aureus isolates than against the terpinen-4-ol.

The water can be a significant risk factor for the occurrence of cattle eimeriosis on farms located in tropical climate regions. This study aimed to assess the viability period of sporulated oocysts of bovine Eimeria spp. in water containing organic matter and to evaluate the efficacy of disinfectants against sporulated oocysts of this protozoa. Two experiments were conducted, each comprising in vitro and in vivo evaluations. In Experiment 1, the viability period of oocysts sporulated in buckets containing a solution composed of a mixture of feces with oocysts, water, and potassium dichromate was assessed. Quantifications and identification of Eimeria spp. oocysts were performed on days + 30, + 60, + 90, and every 30 days thereafter until no more oocysts were detected. Naïve calves were inoculated with this solution kept in the bucket for 6 and 12 months. In Experiment 2, the efficacy of various disinfectants (acetic acid, sodium hypochlorite, ethanol + acetic acid, and ammonia quaternary) against a new solution of sporulated oocysts and pH changes over time (10', 30', and 24 h) were evaluated in the laboratory. The most effective disinfectant was used to treat the water solution and inoculate the calves, and its efficacy was calculated. In Experiment 1, Eimeria spp. oocysts remained viable in the solution for up to 12 months. E. zuernii persisted until the end of the study period. Calves inoculated with the solution kept in the buckets for 6 and 12 months excreted at least four Eimeria species (E. zuernii, E. bovis, E. ellipsoidalis, and E. cylindrica). In Experiment 2, among the tested disinfectants, 3% acetic acid demonstrated the highest efficacy (10' = 80.9%; 30' = 87.9%; 24 h = 91.7%). The pH values of the solutions containing acetic acid ranged from 2.4 to 3.5. Calves that received the inoculum treated with 3% acetic acid did not excrete Eimeria spp. oocysts in feces during the study period (efficacy = 100%). In contrast, all animals in the control group excreted Eimeria spp. oocysts in feces. Future studies should be carried out to better understand the possible effects of cattle drinking water with 3% acetic acid.

Lymphoma is the most common tumor of hematopoietic origin in horses. The course of the disease and clinical signs vary greatly, depending on tumor location and extent. The aim of this report is to describe the occurrence of T-cell-rich oral large B-cell lymphoma with marked local infiltration in a 25-year-old Crioula mare. The mare showed an increase in volume on the right side of its face, dyspnea, anorexia, and progressive weight loss. The clinical assessment showed that the lesion was located in the rostral and caudal sinuses and was markedly invasive to adjacent structures. The autopsy revealed a yellow mass with a soft to firm consistency, infiltrating multiple bones in the skull, and extensively invading the hard palate and masseter muscle. Histologically the mass comprised an undifferentiated malignant neoplasm characterized by a densely cellular neoplasm composed of large CD20 + neoplastic B-lymphocytes admixed with sheets of small, CD3 + reactive T-lymphocytes supported by delicate fibrovascular stroma leading to the diagnosis of oral T-cell-rich large B-cell lymphoma.

BPV-2 infection can cause bladder infections in cattle that, when associated with bracken fern consumption, can progress to cancerous bladder tumors and also present as bovine enzootic hematuria (BEH). This study aimed to evaluate the prolonged natural BPV-2 infection in the blood and urine of cattle, excluding bracken fern consumption. Thirteen Girolando papillomatosis-affected cattle with no bracken fern contact history were monitored for 20 months. Blood, urine, and wart samples were collected for BPV-2 detection and clinical laboratory analyses. All animals showed the presence of BPV-2 in papillomas and blood, and 92.85% showed BPV-2 in urine, suggesting viral dissemination in the urinary tract. Despite all animals being infected with BPV-2, none showed BEH signs during the study. Thus, it was observed that BPV-2 infection alone didn't induce BEH over 20 months, implying a complex interaction with environmental factors or genetic predisposition. This underlines bracken fern consumption's critical role in urinary bladder carcinogenesis. The study underscores BEH's pathogenesis complexity, advocating longitudinal studies to comprehend BPV-2's role fully.

This investigation attempts to evaluate the effect of diet additives via aqueous or ethanolic herbal extracts from Azadirachta indica leaves on Nile tilapia, Oreochromis niloticus. Five dietary categories were assigned to the fish: the first category (N1, with no extract) was kept under control conditions; two categories contained aqueous extract (N2 (1.0 g/kg) and N3 (2.0 g/kg); and two categories contained ethanolic extract, N4 (1.0 g/kg) and N5 (2.0 g/kg), with each group being fed for 60 days. After the feeding trial, Aeromonas hydrophila was injected intraperitoneally into fish for 14 days; fish mortality was recorded during this period. The results showed that the fish-fed dietary A. indica significantly improved growth performance and intestinal health (digestive enzymes and intestinal morphology), especially in the N4 and N5 categories. However, N4 and N5 categories demonstrated a significant decrease in AST and ALT activities and an increase in total protein, serum albumin, globulin, growth hormone (GH), leptin hormone (LEP), hemoglobin, white blood cells, and hematocrit (P  < 0.05) in comparison with the control category (N1). Compared to the control category, the N4 and N5 categories have revealed a significant reduction in MDA activity and improvements in immunological activities (lysozyme, complement C3, and nitric oxide) and antioxidant enzymes (CAT, SOD, and GPX). Moreover, in tilapia-fed A. indica, the expression of IL-8, IL-1β, and Nf-κb genes was downregulated partially in the N4 and N5 categories than the control category. In contrast, the lysozyme, C3, GPX, and CAT genes were upregulated partially at N4 and N5 compared to the control category. Following the bacterial challenge, fish in the N4 and N5 categories also displayed the lowest fish mortality compared to the control category. The ethanolic extract displayed a more potent resistance against the parasite Cichlidogyrus tilapia in vitro than the aqueous and control categories, partially at 2 g/L. According to these findings, an ethanolic neem extract (2.0 g/kg feed) activates the immune system and antioxidant response in Nile tilapia fingerlings, improving growth and fish resistance to parasitic and bacterial infections.

In the gastrointestinal mucosa, there is a close cooperation between secretory immunoglobulin A (SIgA) and the composition of the microbiota, which aims to maintain homeostasis as well as act as a protective barrier. The purpose of this study was to determine the composition of microbiota and SIgA production in different parts of the digestive tract (small intestine, cecum, colon and rectum) of nine healthy horses and its reflection in the feces. For this purpose, we determined: the composition of the microbiome (by next-generation Sequencing of Hypervariable Regions V3-V4 and V7-V9 of the 16 S rRNA gene analysis), the amount of SIgA in the intestinal content samples (by ELISA), as well as the number of IgA-producing cells (IgA+) in the tissue samples (by immohistochemical analysis). Significant differences were observed between the small intestine and the large colon in the composition and diversity of the microbiome, as well as the number of IgA + cells in the mucosal lamina propria and the abundance of SIgA in the intestinal lumen. The small intestine in relation to the large colon is characterised by fewer IgA + cells, more SIgA in the intestinal contents and a less diverse microbiome. However, the cecum appears to be the third separate ecosystem, with a high number of IgA + cells and a diverse microbiome. The fecal sample reflects the current state of the large colon, both in terms of the microbiome and SIgA content; however, it is not known to what extent it may be influenced by dysbiosis in other parts of the digestive tract.

Among pets, cats are the most popular in Europe. Despite the fact, the interest in the safety and quality of their food is much lower compared to the interest of caregivers in the nutrition of dogs. In this research, 27 commercial cat foods were analyzed for mislabeled component composition. Cat foods were divided into a control group, a group of fish foods and a group of other foods with alternative sources of animal protein. Chicken and pig DNA detection was performed using real-time PCR. In this research, 100% of the cat foods contained chicken DNA and 96% of the foods - pig DNA, despite the lack of declaration of these ingredients on the product label. The results indicate that cat food appear to be mislabeled to an even greater extent than dog food. Moreover, manufacturers' declarations in terms of ingredient composition do not reflect the actual composition of commercial products available on the market and intended for everyday feeding of animals. Mislabeling of these products also poses a risk for animals suffering from food allergies.

Porcine circovirus type 3 (PCV3) infection is clinically related to various diseases, including porcine dermatitis and nephrotic syndrome (PDNS)-like disease, respiratory disease, reproductive disorders, and gastrointestinal and neurological diseases. Since PCV3 infection was discovered in 2016, it has developed rapidly and has attracted much attention worldwide. However, specific preventive and therapeutic interventions are currently lacking. In this study, four-dimensional (4D) data-independent acquisition (DIA)-based quantitative proteomics detection combined with bioinformatics analysis were employed to quantitatively identify the differentially expressed proteins in PK-15 cells from the PCV3-infected group compared with those from the uninfected control group. A total of 194 cellular proteins were significantly altered in response to PCV3 infection, including 58 upregulated proteins and 136 downregulated proteins. In our Gene Ontology (GO) enrichment analysis, these differentially expressed proteins were mostly associated with cellular anatomical entities, binding, cellular processes, biological regulation, catalytic activity, metabolic processes, developmental processes, protein-containing complexes and responses to stimuli. Our Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis revealed that the DEPs were predominantly involved in metabolic pathways, the cAMP signaling pathway, protein processing in the endoplasmic reticulum, the PI3K-Akt signaling pathway, and the calcium signaling pathway. For the experiments, Western blotting (WB) was used to confirm the changes in important molecules. The differentially expressed proteins identified should contribute to a greater understanding of the mechanism of PCV3 replication and pathogenesis, as well as the host response.

Evidence of exposure to the pandemic SARS-CoV-2 has been described in numerous animal species, including pets, which are predisposed to coming into contact with this virus due to their close relationship with owners. It has been accepted that dogs are poorly susceptible to this virus and that seroconversion, rather than shedding, occurs following infection, which can occur directly through contact with infected owners or indirectly through environmental contamination. In this study, the seroprevalence of SARS-CoV-2 was evaluated in apparently health hunting and stray dogs of Campania region, southern Italy (sampled in September 2023). A total of 5/112 (4.5%) animals tested seropositive using two different commercial ELISAs. Stray animals had greater exposure than hunting dogs. The feces and blood of each animal were tested with a real-time PCR targeting the nucleocapsid and ORF1ab coding sequences. No animal tested positive in molecular investigations, indicating a past exposure without active infection at the time of sampling.