Frontiers in Veterinary Science最新文献

Early detection of bovine mastitis-causing pathogens is necessary for treatment. As culturing methods are time-consuming, a more rapid detection technique is required. This study investigated the sensitivity, specificity, and detection limit of Gram staining of milk precipitates (milk Gram stain, MGS) to detect bovine mastitis-causing pathogens in milk, as well as the potential of MGS to diagnose inflammation by counting polymorphonuclear leukocytes (PMN). MGS was performed on spontaneous mastitis cases. Culture methods were also used as reference standards to calculate the sensitivity, specificity, and bacterial load in milk to determine the detection limit of MGS. PMN in the mastitic milk were counted using Gram staining. Further, somatic cell counts (SCC), interleukin (IL)-6, IL-8, tumor necrosis factor (TNF)-α, IL-10 and serum amyloid A (SAA) concentrations in mastitic milk were measured using cell counting and enzyme-linked immunosorbent assay. The sensitivity and specificity for all pathogens were 0.62 and 0.90, for Gram-positive were 0.67 and 0.90, and for Gram-negative were 0.50 and 1.00, respectively. The detection limits for Gram-positive and Gram-negative bacteria were 1,560 and 4,680 cfu/mL, respectively. SCC were significantly positively correlated with PMN, milk IL-6, TNF-α, and SAA concentrations, whereas PMN were significantly negatively correlated with milk IL-10 concentration. Our results suggest that MGS may be applied as a rapid method to identify causal pathogens of mastitis before culture results are determined and may also estimate inflammatory status which cannot be detected with SCC. Further clinical trials are required to elucidate whether MGS is useful in clinical veterinary settings.

Hemangiosarcoma is a highly malignant tumor commonly affecting canines, originating from endothelial cells that line blood vessels, underscoring the importance of early detection. This canine cancer is analogous to human angiosarcoma, and the development of liquid biopsies leveraging cell-free DNA (cfDNA) represents a promising step forward in early cancer diagnosis. In this study, we utilized Whole Genome Sequencing (WGS) to analyze fragment sizes and copy number alterations (CNAs) in cfDNA from 21 hemangiosarcoma-affected and 36 healthy dogs, aiming to enhance early cancer detection accuracy through machine learning models. Our findings reveal that similar to trends in human oncology, hemangiosarcoma samples exhibited shorter DNA fragment sizes compared to healthy controls, with a notable leftward shift in the primary peak. Interestingly, canine hemangiosarcoma DNA fragment sizes demonstrated eight distinct periodic patterns diverging from those typically observed in human angiosarcoma. Additionally, we identified seven novel genomic gains and nine losses in the hemangiosarcoma samples. Applying machine learning to the cfDNA fragment size distribution, we achieved an impressive average Area Under the Curve (AUC) of 0.93 in 10-fold cross-validation, underscoring the potential of this approach for precise early-stage cancer classification. This study confirms distinctive cfDNA fragment size and CNA patterns in hemangiosarcoma-affected vs. healthy dogs and demonstrates the promise of these biomarkers in canine cancer screening, early detection, and monitoring via liquid biopsies. These findings establish a foundation for broader research on cfDNA analysis in various canine cancers, integrating methodologies from human oncology to enhance early detection and diagnostic precision in veterinary medicine.

[This corrects the article DOI: 10.3389/fvets.2024.1483990.].

Introduction: Chinese herbal medicines are relatively inexpensive and have fewer side effects, making them an effective option for improving health and treating diseases. As a result, they have gained more attention in recent years. The weaning period is a critical stage in the life of yaks, often inducing stress in calves. Weaning stress, along with dietary changes, can lead to a decline in physical fitness and immune function, making yaks more susceptible to diarrhea and resulting in high mortality rates during this period. Therefore, our study aimed to address this issue by incorporating traditional Chinese medicine (TCM) formulas into the diet of yaks during the weaning period.

Methods: Following a dialectical analysis, three TCM formulas, mainly composed of Paeonia lactiflora, Coptis chinensis, and Dandelion, were identified for their anti-inflammatory, antioxidant, and immune enhancing potentials. We explored the possible molecular mechanisms of these TCM formulas using network pharmacology analysis and investigated their effects on the physiology of yaks through metabolomics.

Results: Network pharmacology analysis revealed several key target proteins in the protein-protein interaction (PPI) network between three formulas and immune-related genes, including PIK3R1, PIK3CA, JAK2, PTK2, and PYPN11. The key target proteins in the PPI network associated with metabolism-related genes included ENPP1, CYP1A1, PTGS1, members of the CYP1 family, and EPHX2. GO analysis of co-targets revealed highly enriched pathways such as protein phosphorylation, plasma membrane, and one-carbon metabolic processes. Metabolomics revealed significant changes in the abundance of metabolites including dimethyl sulfoxide, tyrphostin A25, and thromboxane A2 in the intestines of weaned yaks supplemented with these Chinese herbal compounds. Significant changes were also observed in pathways such as vitamin A metabolism, chloroalkane, and chloroalkene degradation.

Discussion: Based on these findings, it can be inferred that TCM formulas improve the physical fitness of weaned yaks by enhancing antioxidant capacity, boosting immunity, and reducing intestinal inflammation. This study preliminarily elucidates the pharmacological mechanisms by which TCM formulas prevent diarrhea and improve physical fitness in weaned yaks through metabolomics and network pharmacology, paving the way for further evaluation of the effectiveness of these three formulas.

Interactions between humans and livestock could increase the risk of zoonotic disease transmission. In addition, limited knowledge of zoonoses and foodborne diseases among livestock farmers could heighten the risks of foodborne illness and outbreaks of zoonotic diseases. This study evaluated the awareness of zoonotic diseases and preventive practices for zoonotic and foodborne diseases among livestock farmers of the Chitwan, Rupandehi, and Tanahun districts of Nepal by conducting a cross-sectional survey of 280 livestock farmers. They were recruited using the purposive sampling method from October to December 2022. Descriptive statistics revealed that most (72.1%; n = 202/280) livestock farmers were aware of zoonosis. None of the farmers knew about the zoonotic nature of leptospirosis. Two-thirds of pig farmers (67%; n = 12/18) were aware of zoonotic transmission of swine flu, and more than half of the poultry (58%; 50/86) farmers knew about zoonotic avian influenza. The majority of the farmers who had dogs (83%) and cats (89.4%) in their homes or farms knew that rabies can be transmitted to humans from dogs or cats. The multivariable logistic regression analysis revealed that farmers from the Rupandehi district (aOR: 5.56; 95% CI: 2.18-14.22) and Chitwan (aOR: 6.52; 95% CI: 2.46-17.25) had a higher odds of having good preventive practices than those from Tanahun. Also, farmers who had no sickness in the past 6 months after consumption of animal products were three times (aOR: 2.98; 95% CI: 1.48-6.01) more likely to have better practices. Furthermore, secondary education (aOR: 3.64; 95% CI: 1.41-9.44) was a significant positive predictor of good zoonotic diseases and food safety preventive practices. Our study underscores the necessity to enhance Nepalese livestock farmers' awareness and practices regarding zoonotic and foodborne diseases. It emphasizes the importance of understanding risks, effective behavioral change strategies, and engaging farmers in developing zoonotic disease and foodborne illness prevention programs.

[This corrects the article DOI: 10.3389/fvets.2017.00076.].

Sustainability concerns have increased consumer demand for non-animal-derived proteins and the search for novel, alternative protein sources. The nutritional sustainability of the food system without compromising the nutrient quality, composition, digestibility and consumption is pivotal. As with farmed livestock, it is imperative to ensure the well-being and food security of companion animals and to develop sustainable and affordable pet foods. The current pilot study was conducted to determine the effect of greenhouse gas-derived novel, fermented protein ingredient in beagle dogs. The greenhouse gas-derived fermented protein is an alternative protein ingredient with optimal nutritional factors and provides traceability, significantly optimizes the use of land and water, and provides sustainability to the feed value chain of canine diets. Three experimental groups including control, 5 and 10% inclusion of high protein ingredients were included in the study and the results suggest that the fermented protein is palatable and acceptable at 5 and 10% inclusions in the diets of dogs. The present study shows no significant difference in general alertness, clinical symptoms, water consumption and social behavior of dogs between 5 and 10% fermented protein inclusion in canine diets. The diversity of the bacterial community did not change after supplementation with the tested protein source in dogs. Only a few bacterial genera differed significantly in relative abundance between the experimental groups. Feed consumption, faecal scoring and the microbiome data results of this pilot study on the use of novel, methane gas derived, bacterial SCP as a protein ingredient in the canine diets, would pave way for more and more inclusion of such novel alternative protein sources in the pet food industry.

Ossifying fibroma (OF) is a rare, benign fibro-osseous neoplasm that primarily originates from membranous bones. While most frequently documented in equines, OF has also been reported in other species, including dogs, though it remains uncommon. The condition poses significant diagnostic challenges due to its ambiguous presentation, often requiring differentiation from other benign and malignant intraosseous lesions. This case report describes an ossifying fibroma localized to the zygomatic bone in a 9-year-old Hungarian Vizsla. A zygomatic arch ostectomy was successfully performed, and long-term follow-up was excellent. This is only the second documented case of zygomatic localization of OF in a dog, highlighting the rarity of this presentation. The discussion emphasizes the importance of distinguishing OF from other proliferative fibro-osseous lesions, such as fibrous dysplasia (FD) and cemento-osseous dysplasia (COD), and considering the potential for malignancies, such as low-grade osteosarcoma (LG-OSA), to mimic these benign growths. This case contributes valuable insights to the limited veterinary literature on ossifying fibroma, particularly regarding its atypical presentations in canine patients.

Atractylodes lancea, is a herbaceous plant of the Asteraceae family which is a traditional Chinese herbal medicine. It is often used for dehumidification, antiemetics, spleen strengthening and antipyretic effects. Atractylodes lancea is rich in various bio-active substances and has many biological functions, for instance anti-inflammatory, antioxidant and antiviral effects. Therefore, it is widely used in animal production, such as relieving heat stress, protecting intestinal health and regulating immunity. In recent years, it has received widespread attention in green cultivation. This article reviews the biological functions of Atractylodes lancea and looks forward to its application prospects in animal husbandry, in order to provide a theoretical basis for Atractylodes lancea to become a new feed additive in animal production.

Introduction: Antimicrobial resistance (AMR) is a growing threat to the efficacy of antimicrobials in humans and animals, including those used to control bovine respiratory disease (BRD) in high-risk calves entering western Canadian feedlots. Successful mitigation strategies require an improved understanding of the epidemiology of AMR. Specifically, the relative contributions of antimicrobial use (AMU) and contagious transmission to AMR emergence in animal populations are unknown.

Materials and methods: A stochastic, continuous-time agent-based model (ABM) was developed to explore the dynamics of population-level AMR in Mannheimia haemolytica in pens of high-risk cattle on a typical western Canadian feedlot. The model was directly informed and parameterized with proprietary data from partner veterinary practices and AMU/AMR surveillance data where possible. Hypotheses about how AMR emerges in the feedlot environment were represented by model configurations in which detectable AMR was impacted by (1) only selection arising from AMU; (2) only transmission between animals in the same pen; and (3) both AMU-linked selection and transmission. Automated calibration experiments were used to estimate unknown parameters of interest for select antimicrobial classes. Calibrated parameter values were used in a series of Monte Carlo experiments to generate simulated outputs at both the pen and feedlot levels. Key model outputs included the prevalence of AMR by class at multiple time points across the feeding period. This study compared the relative performances of these model configurations with respect to reproducing empirical AMR data.

Results: Across all antimicrobial classes of interest, model configurations which included the potential for contagious acquisition of AMR offered stronger fits to the empirical data. Notably, sensitivity analyses demonstrated that model outputs were more robust to changes in the assumptions underscoring AMU than to those affecting the likelihood of transmission.

Discussion: This study establishes a feedlot simulation tool that can be used to explore questions related to antimicrobial stewardship in the context of BRD management. The ABM stands out for its unique hierarchical depiction of AMR in a commercial feedlot and its grounding in robust epidemiological data. Future experiments will allow for both AMU-linked selection and transmission of AMR and can accommodate parameter modifications as required.