Veterinary and Animal Science最新文献

{"title":"Prediction of body weight in indigenous sheep using random forest regression, support vector regression, and classification and regression trees algorithms","authors":"Ashenafi Getachew Megersa ,&nbsp;Fikrineh Negash ,&nbsp;Abebe Hailu ,&nbsp;Awoke Melak ,&nbsp;Abraham Assefa ,&nbsp;Tesfalem Aseged ,&nbsp;Seble Sinkie","doi":"10.1016/j.vas.2025.100517","DOIUrl":"10.1016/j.vas.2025.100517","url":null,"abstract":"<div><div>This study aimed to develop predictive models for estimating the body weight (BW) of indigenous sheep in Ethiopia using morphometric traits, comparing the performance of random forest regression (RFR), support vector regression (SVR), and classification and regression trees (CART) algorithms. Data were collected from 306 mature sheep (249 ewes and 57 rams) in Tahtay Maichew district of Tigray region, including BW and 16 linear body measurements (LBMs). Descriptive statistics indicated low to moderate variability in BW and key LBMs, with heart girth (HG) and body length (BL) showing the strongest correlations with BW (<em>r</em> = 0.61 and 0.46, respectively). Among the models evaluated, RFR demonstrated superior predictive accuracy, achieving the highest <em>R²</em> values (0.809 training, 0.477 validation) and the lowest root mean square error (RMSE: 1.650 training, 2.825 validation). SVR performed well in training but had lower generalizability in validation, while CART showed the weakest performance overall. Variable importance analysis identified HG as the most influential predictor across all models, contributing 40.90 % in RFR, 16.30 % in SVR, and 68.76 % in CART, often followed by BL and height at withers (HAW). The findings highlight the potential of RFR as a robust tool for BW prediction in resource-limited settings where weighing scales are unavailable. The study provides practical insights for smallholder farmers and breeding programs, enabling improved genetic selection and management practices based on easily measurable morphometric traits, particularly HG. Future research should validate these models with larger, more diverse datasets to enhance their applicability across different agroecological zones and sheep populations.</div></div>","PeriodicalId":37152,"journal":{"name":"Veterinary and Animal Science","volume":"30 ","pages":"Article 100517"},"PeriodicalIF":1.9,"publicationDate":"2025-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145220832","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impacts of dietary sodium alginate as a prebiotic on the oriental river prawn (Macrobrachium nipponense): A comprehensive analysis of growth, physiology, immunity, antioxidant, and metabolism","authors":"Mohammad Ettefaghdoost,&nbsp;Hossein Haghighi","doi":"10.1016/j.vas.2025.100516","DOIUrl":"10.1016/j.vas.2025.100516","url":null,"abstract":"<div><div>The effects of dietary sodium alginate supplementation on <em>Macrobrachium nipponense</em> were evaluated over a 60-day feeding trial, with emphasis on growth, hematological, immune-physiological responses, and metabolic characteristics. Juvenile prawns with an initial average weight of 1.47 ± 0.05 g were assigned to diets containing 0.0 (control), 0.5, 1.0, 2.0, or 4.0 g/kg sodium alginate. Among all the examined water quality indicators, dissolved oxygen (DO) was the only parameter that showed a statistically significant rise with increasing levels of sodium alginate supplementation, with the 4.0 g/kg group showing the maximum value of DO concentration (<em>P</em> &lt; 0.05). Furthermore, growth metrics and survival rates (SR) were significantly enhanced in prawns receiving 2.0 and 4.0 g/kg sodium alginate compared to other treatments (<em>P</em> &lt; 0.05). Hemato-biochemical indices generally decreased following sodium alginate supplementation, whereas levels of high-density lipoprotein (HDL) and low-density lipoprotein (LDL) were elevated (<em>P</em> &lt; 0.05). Most immune parameters and antioxidant enzyme activities demonstrated positive modulation in response to the dietary intervention (<em>P</em> &lt; 0.05), although glutathione peroxidase (GPx), acid phosphatase (ACP), and alkaline phosphatase (AKP) activities did not differ significantly among groups (<em>P</em> &gt; 0.05). Diets supplemented with 4.0 g/kg sodium alginate notably enhanced digestive enzyme activities, promoted beneficial intestinal microbiota, and improved body composition (<em>P</em> &lt; 0.05). Additionally, sodium alginate intake influenced the expression of genes associated with growth, immune function, and metabolism (<em>P</em> &lt; 0.05). Overall, these findings support the dietary inclusion of 4.0 g/kg sodium alginate to optimize growth, physiological condition, and metabolic health in <em>M. nipponense</em>.</div></div>","PeriodicalId":37152,"journal":{"name":"Veterinary and Animal Science","volume":"30 ","pages":"Article 100516"},"PeriodicalIF":1.9,"publicationDate":"2025-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145220833","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Feline lymphoma associated with feline leukemia virus (FeLV) and feline immunodeficiency virus (FIV) infections in Brazil- Systematic review","authors":"Pedro Antônio Bronhara Pimentel ,&nbsp;Antonio Giuliano ,&nbsp;Fernanda Vieira Amorim da Costa ,&nbsp;Paweł Marek Bęczkowski ,&nbsp;Letícia Neves Ribeiro ,&nbsp;Breno Neves Manzalli Oliveira ,&nbsp;Raquel Fernandes Pereira ,&nbsp;Rodrigo dos Santos Horta","doi":"10.1016/j.vas.2025.100514","DOIUrl":"10.1016/j.vas.2025.100514","url":null,"abstract":"<div><div>Lymphoma is the most common neoplasia in cats and is frequently linked with concurrent retroviral infections. Despite preventive strategies, feline leukemia virus (FeLV) and feline immunodeficiency virus (FIV) remain endemic in many parts of the world, with FeLV significantly shortening the lifespan of infected cats. In Brazil and other low-income countries, the incidence of FeLV and FIV remains high. However, the distribution of these retroviruses across South America is still unclear, and their correlation with the anatomical and clinical features of feline lymphoma remains poorly understood. Gaining a deeper understanding of these associations could lead to more effective disease control strategies and better-defined chemotherapy protocols. In this study, we examined the geographical distribution and clinical presentations of feline lymphoma in retrovirus-positive cats in Brazil. A modified bias risk analysis assessed the quality of published studies, and a map was created to highlight areas in need of further research. Initial screening of 703 studies identified 29 relevant ones, encompassing 607 cats with feline lymphoma. After bias analysis, 273 cases were included in this review: 190 were FeLV-positive and FIV-negative, 98 were FeLV-negative and FIV-negative, and 15 were FeLV-negative and FIV-positive. Cases were reported from six Brazilian states and the Federal District of Brazil (2000–2023). The anatomical location of lymphoma varied depending on the cats' viral status, with notable differences in intestinal and mediastinal manifestations. FeLV-negative cats showed an 11.1-fold increased risk (95 % CI=6.0–20.0) for intestinal lymphoma, while FeLV-positive cases had a 7.5-fold increased risk (95 % CI=3.7–15.6) for mediastinal lymphoma. Due to the scarcity of FIV-related cases, analyzing associations was not feasible. Given the apparent association between FeLV-positive status and lymphoma location, further research into this neoplasm is strongly encouraged. We also recommend widespread retrovirus testing and expanded FeLV vaccination efforts in Brazil.</div></div>","PeriodicalId":37152,"journal":{"name":"Veterinary and Animal Science","volume":"30 ","pages":"Article 100514"},"PeriodicalIF":1.9,"publicationDate":"2025-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145220831","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Phenotypic characterization of indigenous Xhosa goat ecotype in three agro-ecological zones in the eastern cape province, South Africa","authors":"Sibulele Praise Ntonga ,&nbsp;Oluwakamisi Festus Akinmoladun ,&nbsp;Ziyanda Mpetile","doi":"10.1016/j.vas.2025.100512","DOIUrl":"10.1016/j.vas.2025.100512","url":null,"abstract":"<div><div>This study characterized the phenotypic attributes of indigenous Xhosa goats across three agro-ecological zones and developed predictive models for estimating body weight. A total of 450 Xhosa goats were sampled using a stratified random approach based on sex, age, and agro-ecological region. Morphometric traits, including body weight (BW), heart girth (HG), body length (BL), wither height (WH), and body depth (RD), were recorded. Data were analysed using the General Linear Model (GLM) of SPSS (v.20) to assess the effects of zones, sex, and age on body traits, while Pearson’s correlation and stepwise regression identified the best predictors of body weight. Results showed significant (p &lt; 0.05) variations in body measurements across zones, with Savanna goats exhibiting superior traits. Males had significantly (p &lt; 0.05) higher BW and body dimensions than females and castrates. Correlation analysis revealed HG (r=0.80), BL (r=0.84), and RD (r=0.82) as the strongest predictors of BW in males, while BL (r=0.66), HG (r=0.65), WH (r=0.62), and RD (r=0.61) were best for females. Stepwise regression identified HG and BL as the best predictors for males, and HG, BL, and SH for females. The predictive models (R² = 0.74–0.85) provide a practical tool for estimating body weight in field conditions. These findings provide practical tools for field-based weight estimation and highlight the importance of conserving the phenotypic diversity of Xhosa goats for sustainable breeding and genetic improvement programs in South Africa.</div></div>","PeriodicalId":37152,"journal":{"name":"Veterinary and Animal Science","volume":"30 ","pages":"Article 100512"},"PeriodicalIF":1.9,"publicationDate":"2025-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145158655","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Differential effects of flunixin meglumine and meloxicam on TNF- α production in LPS-stimulated equine neutrophils in vitro","authors":"Shuntaro Urayama ,&nbsp;Ryo Muko ,&nbsp;Masanori Muranaka ,&nbsp;Hiroshi Mita ,&nbsp;Minoru Ohta ,&nbsp;Hiroshi Matsuda ,&nbsp;Akane Tanaka","doi":"10.1016/j.vas.2025.100513","DOIUrl":"10.1016/j.vas.2025.100513","url":null,"abstract":"<div><div>Systemic inflammatory response syndrome (SIRS) induced by endotoxemia is usually secondary to colitis and is a major cause of high morbidity and mortality in horses. Non-steroidal anti-inflammatory drugs (NSAIDs), such as flunixin meglumine (FM) and meloxicam (MX), are used to improve clinical outcomes in SIRS/endotoxemia. These NSAIDs suppress tumor necrosis factor-alpha (TNF-α) levels; however, the underlying mechanisms remain unclear. The aim of this study was to investigate the inhibitory effects of FM and MX on TNF-α in lipopolysaccharide (LPS)-stimulated peripheral blood mononuclear cells (PBMCs) and neutrophils <em>in vitro</em>. Blood samples were collected from three healthy thoroughbred horses, and PBMCs and neutrophils were isolated using density gradient centrifugation. Cells were cultured with LPS (0.3 ng/mL) and FM or MX (5, 10, or 50 μM). TNF-α gene expression was analyzed using quantitative real-time PCR, and protein levels were measured using ELISA. No significant inhibitory effects of FM or MX on TNF-α gene or protein expression were observed in LPS-stimulated PBMCs. However, FM significantly inhibited the increase in TNF-α protein levels in LPS-stimulated neutrophils in a concentration-dependent manner (<em>p</em> &lt; 0.05). MX showed a similar tendency in LPS-stimulated neutrophils, but the differences were not significant. The regulation of neutrophil-derived TNF-α by FM administration could be a promising therapeutic strategy for equine SIRS/endotoxemia, providing mechanistic insight for optimizing anti-inflammatory therapy.</div></div>","PeriodicalId":37152,"journal":{"name":"Veterinary and Animal Science","volume":"30 ","pages":"Article 100513"},"PeriodicalIF":1.9,"publicationDate":"2025-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145219602","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nutrients utilization and enteric methane emission in zebu cattle fed low quality forages","authors":"Gérard Xavier Gbenou ,&nbsp;Luc Hippolyte Dossa ,&nbsp;Denis Bastianelli ,&nbsp;Ollo Sib ,&nbsp;Laurent Bonnal ,&nbsp;Cécile Martin ,&nbsp;Mohamed Habibou Assouma","doi":"10.1016/j.vas.2025.100511","DOIUrl":"10.1016/j.vas.2025.100511","url":null,"abstract":"<div><div>During the dry season in sub-Saharan Africa, ruminants are commonly fed low-quality forages, such as rangeland fodder and harvested grasses. This study evaluated the effects of four such forages - rangeland fodder (RF), <em>Brachiaria ruziziensis</em> (Bruzi), <em>Andropogon gayanus</em> (Agaya), and <em>Panicum maximum</em> (Pmaxi), all harvested at maturity (24 months) on feed intake, diet digestibility, and enteric methane (eCH₄) emissions. Ten Sudanese Fulani zebu steers (27.7 ± 4.6 months of age, 143.7 ± 15.7 kg of initial body weight - BW) were fed each forage at 2.3 % and 3.2 % of body weight (dry matter – DM basis) over three-week periods, two weeks of adaptation and one week of data collection. The forages differed significantly in chemical composition, affecting feed intake, diet digestibility, and eCH₄ emissions. The Pmaxi, with superior nutritional quality, was the most consumed and had the highest apparent digestibility (0.49; <em>P</em> &lt; 0.001). At low-quality stage, all the forages had similar eCH₄ yield potential (28.5 - 31.6 g/kg DM intake; <em>P</em> = 0.486). Methane conversion rate (Ym) ranged from 8.6 % in Pmaxi to 9.6 % of gross energy intake in Agaya; however, the variation was not statistically significant. Feeding ruminants over ad libitum low-quality forages did not affect their feed intake, diet apparent digestibility and eCH₄ emissions. Measuring eCH₄ emissions induced by these forages at different growth stages can help identify their optimal use for promoting both feed and environmental sustainability.</div></div>","PeriodicalId":37152,"journal":{"name":"Veterinary and Animal Science","volume":"30 ","pages":"Article 100511"},"PeriodicalIF":1.9,"publicationDate":"2025-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145118547","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pilot study on the effects of dapagliflozin on echocardiographic parameters in dogs with symptomatic myxomatous mitral valve disease","authors":"Nakkawee Saengklub ,&nbsp;Anusak Kijtawornrat ,&nbsp;Robert L. Hamlin","doi":"10.1016/j.vas.2025.100510","DOIUrl":"10.1016/j.vas.2025.100510","url":null,"abstract":"<div><div>Myxomatous mitral valve disease (MMVD) is the most common valvular heart disease in geriatric small-to medium-sized dogs. Dapagliflozin, a sodium-glucose cotransporter-2 inhibitor (SGLT-2i), has shown promise in managing heart failure in human patients. This pilot study aimed to explore the short-term effects of dapagliflozin, when added to conventional therapy in symptomatic MMVD dogs. In a prospective, randomized, single-blind study, five dogs with stage C MMVD received dapagliflozin (0.31 mg/kg, PO, q24h) alongside pimobendan, furosemide, and ramipril. A control group (<em>n</em> = 7) received conventional therapy without dapagliflozin. Echocardiographic, electrocardiographic, blood pressure, blood glucose, NT-proBNP, and urinary glucose data were collected at baseline (D0) and follow-up (D28, D84, and D140). Compared to the control group, dogs receiving dapagliflozin showed significant reductions in the percent change from baseline for left atrial to aortic root ratio, left ventricular internal diameter in diastole normalized to body weight, end-diastolic volume, end-diastolic volume index, end-systolic volume, and end-systolic volume index (<em>P</em> &lt; 0.05). Additionally, ejection fraction significantly increased in the dapagliflozin group (<em>P</em> &lt; 0.05). Glucosuria was consistently present only in the dapagliflozin group. These findings suggest that dapagliflozin, when added to conventional therapy, may promote reverse remodeling and improve cardiac function in dogs with stage C MMVD. Further studies with larger sample sizes and longer follow-up are warranted to validate the cardioprotective effects of dapagliflozin in veterinary patients.</div></div>","PeriodicalId":37152,"journal":{"name":"Veterinary and Animal Science","volume":"30 ","pages":"Article 100510"},"PeriodicalIF":1.9,"publicationDate":"2025-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145118394","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of dietary wine lees on oxidative stress, egg quality and yolk lipid stability in laying hens fed with a diet rich in n-3 polyunsaturated fats","authors":"Daniel Mierlita ,&nbsp;Stelian Dărăban ,&nbsp;Adrian Macri ,&nbsp;Ioan Mircea Pop","doi":"10.1016/j.vas.2025.100509","DOIUrl":"10.1016/j.vas.2025.100509","url":null,"abstract":"<div><div>Wine lees (WLs) are a by-product of the winemaking process, but the valorization of WLs as poultry feed has not yet been achieved. Accordingly, the aim of the present study was to evaluate the potential benefits of using WLs as a feed ingredient. To this end, we investigated their effects on serum and hepatic markers of oxidative stress and egg quality in laying hens susceptible to lipid peroxidation by feeding them diets enriched in n-3 PUFA. In addition, lipid profile and oxidative stability of the yolk during storage were evaluated. A total of 128 30-week-old Tetra SL laying hens were divided into four groups (n = 32): the negative control (C–) received a standard diet, while the three other groups (positive control, C+; WL2.5; and WL5) received the standard diet supplemented with 5 % linseed oil rich in n-3 PUFA. In the WL2.5 and WL5 groups, WLs were introduced into the diet at levels of 2.5 % and 5 %, respectively. The increased intake of n-3 PUFA induced oxidative stress, which was evidenced by increased malondialdehyde (MDA) and reduced serum and liver antioxidant enzyme activity. However, these parameters were significantly improved in hens supplemented with WLs. The reduction in n-3 PUFA content in stored eggs was &lt; 19 % in hens fed with WLs, while the reduction exceeded 33 % in the C+ group. In conclusion, WLs can improve egg production and egg quality (yolk color and cholesterol content), the antioxidant status of hens and the oxidative stability of eggs, with the possibility of extending their shelf life.</div></div>","PeriodicalId":37152,"journal":{"name":"Veterinary and Animal Science","volume":"30 ","pages":"Article 100509"},"PeriodicalIF":1.9,"publicationDate":"2025-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145105965","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Infrared thermographic imaging as a promising on-farm method to estimate parasite load in dairy goats","authors":"M. Bernau ,&nbsp;T. Schilling ,&nbsp;H. Eßlinger ,&nbsp;L.E. Hoelzle ,&nbsp;S.A. Goth","doi":"10.1016/j.vas.2025.100506","DOIUrl":"10.1016/j.vas.2025.100506","url":null,"abstract":"<div><div>Faecal egg count (FEC) evaluation is the method of choice to detect parasite load in individuals, but it cannot be used directly on farm. Clinical parameters like body condition scores (BCS), body weight (BW) and milk yield (MY) have been described in this context, but all fail due to a low correlation with FEC. The present study evaluated the utility of clinical parameters, linear body measurements, and infrared thermographic imaging (IRT) in eight dairy goat herds in Germany as potential methods for estimating FEC categories. A total of 893 dairy goats comprising German Fawn Goats (GFG) and German White Goats (GWG) were examined up to six times during three consecutive lactation periods. FEC was determined using individual faecal samples, analysed via the McMaster method. Based on eggs per gram of faeces (EPG), mean FEC across all examinations was categorized into three groups: low (Category 1: ≤500 EPG), medium (Category 2: &gt;500 to ≤1500 EPG), and high (Category 3: &gt;1500 EPG). Statistical analyses were conducted using SAS Studio to identify factors influencing FEC. Significant differences were observed between the two breeds.</div><div>In GFG, animals in Category 3 exhibited significantly lower BCS, BW, chest circumference, and MY compared to those in Category 1. IRT measurements also showed significant differences across FEC categories, with higher IRT values observed in goats with higher FEC. These findings suggest that IRT has potential as a non-invasive, on-farm method for assessing parasitic load. However, further studies are necessary to validate its practical application as a direct health monitoring method.</div></div>","PeriodicalId":37152,"journal":{"name":"Veterinary and Animal Science","volume":"30 ","pages":"Article 100506"},"PeriodicalIF":1.9,"publicationDate":"2025-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145158653","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Antimicrobial resistance and biofilm-forming ability in Staphylococcus aureus causing clinical bovine mastitis in Chitwan, Nepal","authors":"Sujan Adhikari ,&nbsp;Swagat Khanal ,&nbsp;Aakash Marasini ,&nbsp;Prakash Panthi ,&nbsp;Akash Adhikari ,&nbsp;Himal Luitel ,&nbsp;Yagya Raj Pandeya","doi":"10.1016/j.vas.2025.100508","DOIUrl":"10.1016/j.vas.2025.100508","url":null,"abstract":"<div><div>This cross-sectional study, conducted from August to December 2024, investigated the antimicrobial resistance and biofilm-forming abilities of <em>Staphylococcus aureus</em> from clinical bovine mastitis in Chitwan, Nepal. Out of 134 California Mastitis Test-positive milk samples, 32 (23.9%) were confirmed as <em>S. aureus</em> by biochemical tests and species-specific <em>nuc</em> gene PCR. Antimicrobial susceptibility testing of the 32 isolates against 12 antibiotics revealed high resistance rates, particularly to ampicillin (78.1%), nalidixic acid (75.0%), and enrofloxacin (62.5%). The prevalence of multidrug resistance (MDR), defined as resistance to ≥3 antibiotic classes, was alarmingly high, with 27 (84.4%) isolates classified as MDR. Presumptive methicillin-resistant <em>S. aureus</em> (MRSA), detected via cefoxitin resistance, was identified in 14 (43.8%) isolates, all of which were also MDR. Biofilm-forming abilities were assessed qualitatively and quantitatively, with 5 (15.6%) isolates classified as strong biofilm producers. Fisher’s exact test revealed no significant association between biofilm formation and overall MDR status (<em>p</em> &gt; 0.05). However, a statistically significant correlation was found between strong biofilm formation and high-level MDR (resistance to ≥ 4 classes) (<em>p</em> &lt; 0.05), as well as between strong biofilm formation and presumptive MRSA status (<em>p</em> &lt; 0.01). These findings highlight the co-existence of high-level resistance and strong virulence phenotypes in <em>S. aureus</em> from bovine mastitis in Nepal, underscoring the urgent need for robust antimicrobial stewardship, enhanced surveillance, and the development of strategies to mitigate biofilm-associated treatment failures.</div></div>","PeriodicalId":37152,"journal":{"name":"Veterinary and Animal Science","volume":"30 ","pages":"Article 100508"},"PeriodicalIF":1.9,"publicationDate":"2025-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145105967","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}