Veterinary Medicine and Science最新文献

Background: The PAPPA2 gene encodes a metalloproteinase critical for regulating insulin-like growth factor (IGF) bioavailability through cleavage of insulin-like growth factor-binding protein 5 (IGFBP5). While its role in human and murine reproduction is documented, its function in sheep reproductive traits remains underexplored.

Objective: This study aimed to investigate the differential expression patterns and polymorphisms in PAPPA2 gene across diverse sheep breeds and their association with litter size.

Methods: Genotyping of two single nucleotide polymorphisms (SNPs; g.55757202C>A and g.55924884C>G) was performed in 760 ewes from six breeds. Three high-fertility Small Tail Han ewes and three low-fertility Tibetan ewes were selected for tissue-specific expression analysis. Associations between SNPs and litter size were statistically analysed, and bioinformatics tools were employed to assess structural impacts of mutations.

Results: The g.55924884C>G SNP exhibited a significant association with litter size in Small Tail Han sheep across parities (p < 0.05). qPCR revealed markedly higher PAPPA2 expression in low-fertility Tibetan sheep ovaries compared to high-fertility Small Tail Han sheep (p < 0.05). Bioinformatics analysis indicated that the g.55924884C>G mutation induced substantial alterations in the secondary and tertiary structures of PAPPA2 protein, while g.55757202C>A had minimal structural impact, which may be the reason for the change in litter size caused by the g.55924884C>G mutation.

Conclusions: The g.55924884C>G polymorphism in PAPPA2 gene significantly influences ovine litter size and may serve a genetic marker for selective breeding.

Sustainable poultry production is essential for small-scale farmers in resource-limited regions such as central and southern Ethiopia, where feed costs account for 60%-70% of production expenses. This study evaluates fruit and vegetable peels including potato, banana, avocado, mango, cassava, papaya, beetroot and pumpkin as alternative feed ingredients for sustainable poultry nutrition by analysing their nutritional profiles and anti-nutritional factors (ANFs). Data from 360 households across Hadiya, Wolaita and Gamo zones revealed potato peel as the most utilized (27.5%, p < 0.05), exhibiting the highest metabolizable energy (3.17 Mcal/kg DM) and crude protein (7.33%, p < 0.001). Banana peel ranked second (18.89%) with moderate protein (5.5%) and high potassium (482 mg/100 g, p < 0.001), while cassava peel showed exceptional calcium (178.7 mg/100 g) and phosphorus (97 mg/100 g) content (p < 0.001) but required detoxification due to elevated oxalates (283.3 mg/100 g) and tannins (0.7 mg/100 g, p < 0.001). Nutritional analyses revealed significant variations in ash content (4.26%-7.83%), crude fibre content (5.7%-18.3%) and mineral composition across peels (p < 0.001). Despite regional adoption differences (p < 0.05), all peels showed potential as sustainable, cost-effective feed alternatives that align with circular economy principles. In conclusion, pumpkin peel exhibited the highest overall nutritional value among the evaluated fruit and vegetable peels. The study further underscores the importance of applying appropriate processing methods to reduce ANFs, while also highlighting the environmental and economic benefits of utilizing locally available agro-wastes as sustainable poultry feed resources. Further research should optimize detoxification techniques and inclusion levels to maximize poultry productivity and safety.

Peptides alone often exhibit limited immunogenicity, necessitating the development of effective antigen delivery systems to facilitate recognition and presentation, ultimately eliciting robust immune responses and activating T and B lymphocytes. Filamentous bacteriophages, such as M13, are recognized as efficient platforms for peptide expression and presentation via their capsid surfaces. The conserved amino acid sequence HA2 1-9 (GLFGAIAGF) from the haemagglutinin (HA) transmembrane protein of Influenza A virus (IAV) has been identified as a promising immunogen for eliciting broad-spectrum immune responses against diverse IAV strains. In this study, the N-terminal fragment of Protein VIII from M13 phage was genetically engineered to express the conserved HA2 1-9 sequence. High-level expression of the HA2 peptide on the phage surface was confirmed via immunoblotting analysis. Birds were intramuscularly vaccinated with the recombinant M13 phage displaying the HA2 peptide and subsequently challenged intranasally with the H9N2 IAV subtype. The results demonstrated that the GLFGAIAGF peptide elicited specific immunoglobulin Y (IgY) antibody responses against the HA2 peptide in birds. However, vaccination did not lead to a significant reduction in the shedding of H9N2 virus in the trachea and cloaca. This study highlights the potential of phage display platforms for antigen expression and immune activation. While the conserved GLFGAIAGF epitope successfully induced specific IgY responses, the limited efficacy in reducing viral shedding underscores the need for further optimization of the vaccination regimen, as well as investigation of alternative delivery routes, such as intranasal or oral administration, to enhance protective efficacy.

Objective: This study was designed to determine the virulence factors and antimicrobial resistance profiles of Escherichia coli pathotypes isolated from neonatal calf diarrhoea in Western Iran.

Methods: A total of 350 diarrhoeic faecal samples were collected. The samples were assessed for the presence of E. coli phenotypically. The molecularly confirmed isolates were further classified as different pathotypes on the basis of the genotypic traits. Additionally, the distribution of diverse serotypes and the antimicrobial resistance profile of the isolates were determined.

Results: Among the 307 E. coli isolates, 235 isolates could be categorized as the following pathotypes: enterohaemorrhagic E. coli (EHEC), 36.59%; enteropathogenic E. coli (EPEC), 20.42%; enterotoxigenic E. coli (ETEC), 14.46%; Shiga-toxigenic E. coli (STEC), 12.34% and necrotoxigenic E. coli (NTEC), 11.48%. STEC O157:H7 was detected in four isolates. O103 and O15 serotypes were the most prevalent. Totally, high rates of antibiotic resistance were observed, with the most common resistance for penicillin (99.14%) and tetracycline (94.46%), and the least common for nitrofurantoin (62.16%) and neomycin (65.10%).

Conclusion: The results substantiated the potential reservoirs of calves for various E. coli pathotypes in the region. With an emphasis on the identification of important O-serogroups and the high rates of antimicrobial resistance among the isolates, the need for continuous monitoring, strict biosecurity measures in cattle farms and proper antibiotic stewardship are underscored to prevent the transmission of pathogenic and resistant strains to humans.

Background: Equine lameness diagnosis largely relies on subjective visual assessments, which can be biased. Although marker-based methods, force plates and inertial measurement units (IMUs) provide objective measurements, they require specialized setups. Vision-based algorithms offer a portable, markerless alternative, but their accuracy needs thorough testing.

Objectives: To evaluate a custom vision-based algorithm for estimating the groundline across multiple camera angles, including handheld use in horses trotting on a treadmill.

Study design: Experimental comparative study.

Methods: Eight Standardbred trotter mares were recorded trotting on a high-speed treadmill using seven iPhones positioned at various heights and angles, including a handheld device. A trained deep neural network algorithm placed 2D keypoints on each video frame. Vertical Displacement Signals (VDS) for the eye, withers and croup (tuber sacrale) were computed relative to either an algorithm-estimated or a fixed treadmill groundline. Maximum (Maxdiff) and minimum (Mindiff) stride values were compared using Bland-Altman analysis, scatter plots and histograms. The effect of handheld use on variability and accuracy was assessed by comparing results from a handheld camera to those from a static camera.

Results: Groundline estimation closely matched the fixed reference, exhibiting near-zero mean angle error and low mean average error (MAE = 0.45°; n = 242.192). Maxdiff and Mindiff stride-level (n = 36.981) MAE were 0.5 mm, with clinically acceptable additional variability introduced by handheld use at the trial level (Maxdiff and Mindiff MAE < 1.8 mm; n = 357).

Main limitations: Treadmill-based data and a single breed/coat colour may limit generalizability to other settings.

Conclusions: The vision-based algorithm accurately estimates the groundline and stride VDS parameters from various camera setups, including handheld. Further validation in diverse environments and against other objective gait analysis systems is recommended.

The aim of this study was to evaluate the effects of Nigella sativa supplementation on the immune response, disease incidence, mortality rate and growth performance of suckling Zaraibi goat kids. Sixty suckling Zaraibi goat kids (33 males and 27 females) with an average body weight of 3.03 ± 0.02 kg were divided into three groups: a control group (G1), which was fed a basal diet and two treatment groups (G2 and G3), which were fed the same diet supplemented with 0.5 g and 1.0 g of N. sativa per kid per day, respectively, for 84 days. The data were analysed with a general linear model to assess the differences among dietary treatments, and Duncan's multiple range test was applied for post hoc comparisons. Compared with G1, the body weight of the kids in the treatment groups was significantly higher (p < 0.05). Consequently, total weight gain and average daily gain were significantly raised in the G2 and G3 groups compared to the control group (p < 0.05). In addition, the feed intake was significantly higher, whereas the feed conversion ratio was significantly lower in G3 compared to G1 (p < 0.05). The outputs of weaning weight and the adjusted mortality rate increased significantly (p < 0.05), in line with the increasing levels of N. sativa in G2 and G3. G3 fed the highest level of N. sativa and registered the lowest occurrence of diseases, followed by G2, whereas the control, G1, showed the highest incidence (p < 0.05). In particular, the mortality rate decreased significantly (p < 0.05) with the inclusion of N. sativa, showing a clear dose-dependent effect. The highest mortality rate was observed in G1 (15%), followed by G2 (10%), while G3 exhibited the lowest mortality rate (5%) (p < 0.05). The plasma IgG levels were significantly higher in the G2 and G3 groups compared to the control group (p < 0.05), with G3 exhibiting increased IgG levels than G2 (p < 0.05). These findings suggest that N. sativa supplementation can enhance the health and growth performance of suckling Zaraibi goat kids, contributing to sustainable farming practices and potentially reducing antibiotic use in livestock.

Background: Hilar hepatocellular tumours in dogs pose a significant surgical challenge due to their proximity to major hepatic vessels. Preoperative reduction of tumour volume and vascular involvement may enhance surgical feasibility and improve outcomes.

Objectives: To describe the use of transarterial chemoembolization (TACE) as a neoadjuvant strategy for downsizing hilar hepatocellular masses in dogs, thereby enabling safe and effective surgical resection.

Methods: A 12-year-old spayed female Beagle presented with a 5.1 cm × 8.1 cm × 8.9 cm hepatic mass in the left medial lobe, with suspected invasion into the left lateral lobe at the hilus. Conventional TACE was performed using idarubicin-loaded ethiodized oil emulsions and gelatin sponge particles. Four weeks after TACE, computed tomography was performed to assess the tumour response, followed by surgical resection 2 weeks later.

Results: The dog experienced mild abdominal discomfort and transient liver enzyme elevation following TACE, consistent with post-embolization syndrome. Tumour volume decreased by 38%, providing adequate space for vascular dissection and enabling successful resection with clear surgical margins. The dog recovered without major complications, remained recurrence-free 22 months postoperatively, and was still alive at the time of manuscript submission. Cytology confirmed a hepatocellular origin, although histopathology was non-diagnostic due to diffuse necrosis.

Conclusions: Preoperative TACE may be an effective neoadjuvant therapy for reducing tumour size and facilitating surgical access in dogs with large liver tumours. This approach may present a viable option for dogs with hepatocellular tumours initially considered difficult to resect due to vascular involvement.

Background: A healthy gut microbiota enhances immune function and reduces infection susceptibility in neonatal calves.

Objectives: This study evaluated the probiotic efficacy of Lactobacillus amylovorus, Lactobacillus reuteri and Lactobacillus johnsonii isolated from Korean indigenous calves in improving gut microbiota, inhibiting pathogen colonization and enhancing immunity in newborn calves.

Methods: These strains were fed orally at 10⁹ colony-forming unit (CFU)/g in a mixture, five times every 2 days. Experiment 1 targeted calves under 10 days old, and Experiment 2 targeted calves less than 1 day old. Faecal and blood samples were collected for microbial, pathogen and blood analyses.

Results: Probiotic-fed calves (LA group) showed significantly increased gut microbial diversity on Day 10 compared to Day 0 and control group (C group), as indicated by higher Shannon and Simpson indices. Beneficial bacteria such as Faecalibacterium prausnitzii showed higher abundance, whereas potentially harmful bacteria like Bacteroides fragilis showed lower abundance. On Day 20, pathogens were detected in 25% of calves in the LA group, compared to 100% in the C group, which was significantly lower. Blood parameters in the LA group remained stable, whereas the C group showed fluctuations. Mild metabolic acidosis was observed in the C group in Experiment 2. In Experiment 2, the LA group had significantly higher total protein and γ-globulin than the C group on Day 5.

Conclusions: The LA group showed beneficial bacteria proliferation, harmful bacteria suppression, pathogenic infection inhibition and improved serum protein status, suggesting that these strains may contribute to the health management of calves under 10 days old.

A 3-year-old Connemara X filly was referred to a UK equine hospital for further investigation of unilateral nasal discharge and facial swelling. Diagnostic imaging documented the presence of a heterogenous, soft tissue opacity with areas of focal mineralisation within the right paranasal sinuses, completely obliterating the nasal cavity, in addition to endodontic disease and significant periapical pathology associated with the right permanent fourth premolar (Triadan 108). Subsequent histopathologic examination confirmed the mass as a fibro-inflammatory polyp.