Veterinary Sciences最新文献

Recently, low pathogenic avian influenza virus (LPAIV), including H9N2 subtype, has been common clinical epidemic strains, and is widely distributed globally. The PB1 protein is a key component of the viral RNA polymerase complex (vRNP), and is vital to viral transcription and translation. In this study, to investigate the antigenic determinants in the PB1 protein, the truncated PB1 sequence (1bp-735bp) from H9N2 subtype AIV was amplified with PCR, and expressed in plasmid pET-28a (+). After purification, the recombinant PB1 protein was used to immunize BALB/c mice. Following immunization, hybridoma cells producing PB1-specific monoclonal antibodies were generated through the fusion of splenic lymphocytes with SP2/0 cells. Then, four stable hybridoma cell lines (5F12, 5B3, 2H9, and 3E6) were screened using indirect ELISA and Western blotting. Furthermore, two antigenic sites, 67NPIDGPLPED76 and 97ESHPGIFENS106, were identified through the construction of truncated overlapping fragments of the PB1 protein. These sites were conserved among 28 AIV strains, and were located on the PB1 protein surface. The findings offer a theoretical reference for the development and improvement of H9N2 vaccines and offer biological materials for virus detection during AIV infection mechanisms.

Background: The role of neuroinflammation in epileptogenesis has been previously explored, and several biomarkers have been identified as being relevant in assessing the intensity of the inflammatory process. In human medicine, an increased C reactive protein (CRP) blood concentration and/or neutrophil-to-lymphocyte ratio (NLR) is considered a constant finding of epileptic activity. In veterinary medicine, only a few studies have been published regarding both of these topics.

Hypothesis/objectives: Our aim was to assess the C reactive protein blood concentration and the neutrophil-to-lymphocyte ratio in epileptic dogs, regardless of etiology.

Method: This retrospective study was based on changes in routine blood parameters in 59 dogs with epileptic activity.

Results: An increased C reactive protein concentration was observed mostly in the dogs affected by structural epilepsy, and all epileptic dogs displayed abnormal neutrophil-to-lymphocyte values.

Conclusions: Based on the authors' knowledge, this is the first report regarding the NLR in epileptic dogs. Both the CRP concentration and the NLR might be considered feasible non-specific markers of the neuroinflamation involved in epileptogenesis and might be used in the diagnosis of and therapeutic approach to cluster seizures in dogs with idiopathic epilepsy and in patients with structural epilepsy. Dogs diagnosed with IEis and high CRP concentrations and NLRs may be subject to non-documented cluster seizures. Both CRP and the NLR have limited diagnostic value in dogs with reactive seizures.

Cancer is a complex pathological condition associated with substantial rates of mortality and morbidity in both humans and animals. Mammary gland tumors in intact female dogs are the most prevalent neoplasms. Surgical intervention remains the primary treatment choice. Alternative therapeutic options have emerged, with histopathological examination being fundamental to confirm the diagnosis and to decide the best therapy. This research focused on the clinicopathological, immunohistochemical, and cytogenetic aspects of canine mammary tumors (CMTs). Most of the animals were mixed-breed, with the majority being older than seven years, and only 16.7% had been spayed before surgery. Caudal abdominal and inguinal mammary glands were the most affected, with regional mastectomy being the predominant treatment (75.0%). Of all the tumors, 29.1% were benign, while 70.9% were malignant. Complex adenoma was the most common benign tumor, whereas tubulopapillary carcinoma was the most common malignant type. Grade III tumors (17.6%) were the least encountered, while grades I and II exhibited a similar prevalence (41.2%). All the carcinomas were classified as luminal, and cytogenetics analysis demonstrated a high chromosomal instability with significant aneuploidy observed in all cases and polyploidy detected in 62.5%. This study holds significance as canine and human breast cancers share similar characteristics, suggesting that dogs could be a valuable model for human breast cancer research. Further studies with larger sample sizes are needed to enhance our understanding of CMTs.

This study aims to investigate the impact of carvacrol and thymol on the quality of Beni Arouss buck semen stored in skim milk at 4 °C. Ejaculates were collected from eight Beni Arouss bucks weekly for 11 weeks, pooled, and then divided into three equal parts. Samples were diluted to 400 × 10⁶ sperm/mL in skim milk (control) and skim milk supplemented with a single dose of 200 µM carvacrol and thymol each. Evaluations of sperm motility, viability, abnormalities, membrane integrity, lipid peroxidation, and bacterial growth were conducted at 0, 6, 24, and 48 h of liquid storage at 4 °C. After 48 h of storage, the results indicate that the addition of carvacrol positively influences total and progressive motility and viability. However, it also leads to a decrease in lipid peroxidation and bacterial growth compared to the control group (p < 0.05). Thymol showed similar results to carvacrol, except for progressive motility (p > 0.05). Bacterial growth was negatively correlated with total and progressive motility and viability (p < 0.05), while no correlation between lipid peroxidation and these parameters was observed (p > 0.05). In conclusion, the addition of carvacrol and thymol to skim milk extender moderately improves the quality of Beni Arouss buck semen after 48 h storage at 4 °C due to its antimicrobial activity.

During dental scaling in dogs under general anaesthesia, contamination of the peripheral intravenous catheter (PIVC) is unavoidable due to splatter and the generated aerosol. Bacterial contamination was compared between two commonly used PIVC placement sites. Thirty-nine client-owned dogs with a minimum length from their nose to their tail base of 50 cm were randomly assigned to receive a PIVC in either their cephalic or saphenous vein. Irrespective of the PIVC placement site, brain heart infusion agar dishes were placed in the cephalic and saphenous vein areas. Their lids were closed 0, 5, and 10 min into the procedure. Contamination was measured by counting the colony-forming units after incubation on different substrates. The data were analysed with descriptive statistics, ANOVA, and ANCOVA (p < 0.05). The cephalic vein area showed a significantly higher bacterial load than the saphenous vein area (p ≈ 0.0) regardless of the length of the dog. Furthermore, the dorsal PIVC injection ports were sampled before and after scaling, and the colonies isolated were counted and subjected to MALDI-TOF-MS for identification. The bacteria mainly belonged to the genera Staphylococcus, Neisseria, and Bacillus. Our results suggest that for dental scaling in dogs, the PIVC should be placed in the pelvic limb whenever possible to reduce the potential risk of contamination.

Background: This study aimed to evaluate the suppressive effects of β-hydroxybutyrate (BHB) administration on lipopolysaccharide (LPS)-induced inflammation in broiler chickens.

Methods: Twenty-day-old male broiler chickens were randomly allocated to three groups, each of which was treated with saline (control), intraperitoneal administration of LPS [1.5 mg/kg body weight (BW), Escherichia coli O127:B8], or LPS plus BHB (3 mmol/kg BW).

Results: Plasma albumin and total protein concentration were significantly reduced by LPS administration, while BHB co-treatment partially attenuated the effects. The LPS treatment significantly induced plasma aspartate and alanine aminotransferase activities, and interleukin (IL)-6 concentration, with the increases suppressed by BHB co-treatment (p < 0.05). The LPS treatment significantly increased the gene expression levels of IL-1β, IL-6, and IL-18 in the spleen and peripheral blood monocytes (PBMC), while the increases were partially attenuated by BHB in the spleen. Relatively higher levels of BHB dehydrogenase 1 and succinyl-CoA:3-ketoacid CoA transferase were observed in the spleen and skeletal muscle, while these gene levels were lower in PBMC and the liver.

Conclusions: The present results suggest that BHB can suppress LPS-induced inflammation, in which ketolytic enzyme expression levels may be involved in broiler chickens.

Body condition score (BCS) is a common tool used to assess the welfare of dairy cows and is based on scoring animals according to their external appearance. If the BCS of dairy cows deviates from the required value, it can lead to diseases caused by metabolic problems in the animal, increased medication costs, low productivity, and even the loss of dairy cows. BCS scores for dairy cows on farms are mostly determined by observation based on expert knowledge and experience. This study proposes an automatic classification system for BCS determination in dairy cows using the YOLOv8x deep learning architecture. In this study, firstly, an original dataset was prepared by dividing the BCS scale into five different classes of Emaciated, Poor, Good, Fat, and Obese for images of Holstein and Simmental cow breeds collected from different farms. In the experimental analyses performed on the dataset prepared in this study, the BCS values of 102 out of a total of 126 cow images in the test set were correctly classified using the proposed YOLOv8x deep learning architecture. Furthermore, an average accuracy of 0.81 was achieved for all BCS classes in Holstein and Simmental cows. In addition, the average area under the precision-recall curve was 0.87. In conclusion, the BCS classification system for dairy cows proposed in this study may allow for the accurate observation of animals with rapid declines in body condition. In addition, the BCS classification system can be used as a tool for production decision-makers in early lactation to reduce the negative energy balance.

A cross-sectional study was carried out, between April 2021 and June 2022, to understand the role of dogs in the circulation of rickettsiosis in Tunisia. The presence of specific IgG antibodies against Rickettsia conorii was analyzed by indirect immunofluorescence test. By qPCR, blood and ticks were collected from 136 dogs examined at the Canine Department of National School for Veterinary Medicine of Tunisia. These dogs were also analyzed to detect Rickettsia DNA. The rate of Rickettsia seropositivity in 136 dogs was 55.14%. A total of 51 (53%) seropositive dogs showed clinical and biological signs such as fever and anorexia as well as thrombocytopenia and anemia. By qPCR, targeting the mitochondrial 16S rRNA gene, no Rickettsia DNA was detected in the blood. On the other hand, qPCR followed by sequencing revealed the presence of R. conorii subsp. raoultii in 7 tick pools of the 51 pools composed of the 227 ticks collected. A One Health approach to raise the awareness of dog owners to control tick infestations is imperative, given the dangers of canine zoonoses.

This study aimed to describe computed tomography (CT) characteristics of histologically confirmed cirrhosis and to compare these CT characteristics between compensated and decompensated cirrhosis. Sixteen dogs who underwent contrast CT and histopathological examinations were included; eleven dogs were assigned to the compensated group, and five dogs were assigned to the decompensated group. Irregular hepatic contours with a diffuse nodular distribution and hepatic lymph node enlargement are common concomitant features of cirrhotic livers on CT images. The enhancement patterns of the regenerative nodules and hepatic parenchyma were not significantly different from each other. Hypoattenuating areas with delayed contrast enhancement indicating fibrotic tissue were confirmed in 56.3% of cases. Hypoattenuating wedge-shaped area or nodule with minor or no contrast enhancement (histopathologically confirmed as focal necrosis) were confirmed in 37.5% of cases. Among CT variables, only normalized liver volume and portal vein-to-aorta ratio were significantly lower (p = 0.038 and 0.003, respectively) in the decompensated group. In conclusion, this study presented the CT features of cirrhosis and identified CT features that can discriminate between compensated and decompensated cirrhosis. Specifically, lower normalized liver volume and the portal vein-to-aorta ratio might be useful indicators for the progression of cirrhosis to the decompensated phase.

African swine fever is an extremely infectious viral disease that can cause nearly 100% mortality in domestic pigs. In this study, we isolated an ASFV strain HB31A and characterized it using hemadsorption assay, immunofluorescence assay, and electron microscopy. We then performed animal experiments on 20-day-old pigs through intramuscular and oronasal inoculations with HB31A. Pigs in the intramuscular group exhibited more consistent clinical disease, with an incubation period of 4.33 ± 0.47 days and a 100% mortality rate within 6.67 (±0.47) days post-inoculation (dpi). In contrast, the oronasal group experienced a longer course of disease, with an incubation period of 6.00 ± 0.82 days. Two out of three pigs in the oronasal group died at 8 and 10 dpi, while the surviving pig exhibited chronic disease and persistent infection, intermittently excreting ASFV through the oral, nasal, and rectal pathways. Virus DNA was found in oral, nasal, and rectal swabs at 1-3 dpi in the intramuscular group and at 3-5 dpi in the oronasal group. In summary, HB31A is highly lethal to domestic pigs, and field-infected pigs have the potential to develop non-lethal, chronic disease and persistent infection, with intermittent viral shedding, even when infected with a highly virulent strain. These findings offer a valuable understanding of the viral dynamics and pathogenicity of ASFV and highlight the difficulties in diagnosing, preventing, and controlling African swine fever.