Veterinary Quarterly最新文献

Marek's disease virus (MDV) has become an increasingly virulent pathogen in the poultry industry despite vaccination efforts to control it. Brazil has experienced a significant rise of Marek's disease (MD) outbreaks in recent years. Our study aimed to analyze the complete meq gene sequences to understand the molecular epidemiological basis of MD outbreaks in Brazilian vaccinated layer farms. We detected a high incidence rate of visceral MD (67.74%) and multiple circulating MDV strains. The most prevalent and geographically widespread genotype presented several clinical and molecular characteristics of a highly virulent strain and evolving under positive selective pressure. Phylogenetic and phylogeographic analysis revealed a closer relationship with strains from the USA and Japan. This study sheds light on the circulation of MDV strains capable of infecting vaccinated birds. We emphasize the urgency of adopting preventive measures to manage MDV outbreaks threatening the poultry farming industry.

Zinc (Zn) and iron (Fe) are necessary for structural and metabolic functions of the body like, immune competence, physical growth, reproductive function, and neurobehavioral development. The deficiency of micronutrients is a severe public health distress in nearly all developing countries which leads to the syndrome of malnutrition mostly in children and women. The present study was conducted to compare the effect of different levels of Fe and Zn on feed intake (FI), feed conversion ratio (FCR), daily egg production, and Fe and Zn depositions in the egg yolk of laying hens. For this purpose, 80 commercial laying birds were allocated into four groups consisting of four replicates each (n = 5). The basal ration was provided to the control group (C) while three different levels (100, 200, and 300 mg/kg diet/element) of Fe and Zn (1:1) were provided to the FZ100, FZ200, and FZ300 groups, respectively. Overall FI, hen day egg production, and FCR were not affected (p > 0.05). The Fe and Zn content in egg yolk were significantly increased in the FZ300 group after 4 weeks of supplementation. The cost per egg produced in response to different levels of Fe and Zn supplementation was not affected however a numerical increase in cost/egg was found in the FZ300 group. In conclusion, Fe and Zn supplementation (300 mg/kg diet/element) significantly enhanced the egg Fe and Zn contents without adversely affecting production parameters including FI, egg production, and FCR of laying hens.

The aim of the present study was to assess the effects of different levels of hempseed (HS) on growth performance, immunity and gut health in broiler chickens. A total of 192 Hubbard broiler chicks were divided into four groups and fed HS as follow: control (HS0), HS 10% (HS-10), HS 15% (HS-15) and HS 20% (HS-20). The study on HS supplementation in broilers revealed no significant impacts on feed intake during the starter (p = .2294) and finisher phases (p = .2294), or overall (p = .0944), though numerical increases were noted with higher HS levels. Body weight gain showed no significant influence in the starter and finisher phases, with overall weight gain also not significantly different (p = .0944), but numerically higher with increased HS. Feed conversion ratio was unaffected in the starter (p = .6986) and finisher phases (p = .6425), and overall (p = .2218). Dressing percentage (p = .1062) and mortality (p = .1631) were not significantly altered, but HS-20 had the highest dressing percentage and lowest mortality numerically. White blood cell counts increased significantly (p = .0377), especially in HS-15 and HS-20 groups. IgM and IgG production was higher in HS-20 on day 28 (p = .021). Gut pH (p > .05) and intestinal histomorphology (p > .05) were not significantly affected, although villus height increased numerically with higher HS levels. These results suggest potential benefits of HS, especially at higher inclusion levels. In conclusion, the obtained results indicated that HS incorporation into the diet of broilers did not affect the growth performance and gut health; however, the immune responses were significantly higher at 15 and 20% levels.

Lumpy skin disease (LSD) is an economically significant, emerging viral disease of Cattle and Buffaloes. This study aimed to investigate the causes of high mortality in a recent LSD epidemic in India. We examined 1618 animals across seventy outbreaks and conducted post-mortem on 48 cattle out of 513 clinically suspected LSD cases. The morbidity, mortality and case fatality rates recorded were 31.70%, 2.97 and 9.37% respectively. Disease stages were categorized as early (20.81%), mid (42.02%), and late (37.17%) and the distribution of skin lesions was classified as mild (34.14%), moderate (39.39%), and severe (26.47%). Post-mortem findings revealed systemic infection with necrotic and ulcerative nodules on multiple internal organs. Histologically, necrotizing vasculitis and mononuclear cell infiltration with intracytoplasmic inclusions were observed in various organs. The highest viral load was found in skin nodules/scabs, trachea, tongue, and lymph nodes. The viral load was significantly higher in mid- and late-stages of skin nodules and internal organs; whereas, blood from early-stage showed high viral load. The expression of Th1-type and Th2-type cytokines varied significantly across different stages of the disease. The downregulation of the apoptotic intrinsic and upregulation of the extrinsic pathway genes, suggesting that the latter plays a role in LSDV infection. Genetic analysis revealed that the LSD virus (LSDV) isolates were derived from a Kenyan ancestral strain with unique nucleotide changes in RPO30 and P32 gene. In conclusion, the high mortality in the recent Indian LSD epidemic can be attributed to a newly identified, highly virulent strain of LSDV causing systemic infection.

Dogs that had splenectomy are predisposed to fatal thrombotic conditions, and thrombocytosis is a risk factor for post-splenectomy hypercoagulability. However, in veterinary medicine, there are no specific therapeutic approaches for managing this hypercoagulability. This study aimed to determine the preventive effect of clopidogrel on post-operative hypercoagulability during the first 2 weeks post-splenectomy in dogs with splenic masses. This study included 12 dogs that had splenectomy. Seven dogs received no treatment (group A), and five were treated with clopidogrel (group B). Clopidogrel was loaded at 10 mg/kg on day 2 and continued at 2 mg/kg until day 14. Blood samples were collected on the day of surgery and 2, 7, and 14 days after splenectomy in both groups. In group B, thromboelastography (TEG) was performed on the same days. In group A, there was significant elevation of platelet counts on days 7 (p = 0.007) and 14 (p = 0.001) compared to day 0. In group B, the platelet counts were significantly elevated on day 7 (p = 0.032) but no significant difference was found on day 14 compared to day 0. Platelet counts on day 14 were significantly higher in group A than in group B (p = 0.03). The lower platelet counts were correlated with alterations in TEG parameters, and no significant differences were found in the K and α-angle values at all postoperative assessment points compared to day 0. Our study suggests that clopidogrel may reduce post-operative thrombocytosis and hypercoagulability in dogs that undergo splenectomy for splenic masses.

Polyomaviruses (PyVs) are small double-stranded DNA viruses able to infect species across all vertebrate taxa. In cetaceans, PyVs have been reported only in short-beaked common dolphin (Delphinus delphis), common bottlenose dolphin (Tursiops truncatus) and killer whale (Orcinus orca). Herein, we surveyed PyV in 119 cetaceans (29 mysticetes and 90 odontocetes) stranded along the Brazilian coast, from 2002 to 2022, comprising 18 species. DNA extracted from the lungs was tested using a nested PCR targeting the major capsid protein gene of PyV. Polyomavirus was detected in lung samples of 1.7% (2/119) cetaceans: two juvenile female Guiana dolphins (Sotalia guianensis) stranded in Rio de Janeiro (Rio de Janeiro state) and Guriri (Espírito Santo state), in 2018. Both retrieved sequences were identical and presented 93.3% amino acid identity with Zetapolyomavirus delphini, suggesting a novel species. On histopathology, one of the PyV-positive individuals presented basophilic intranuclear inclusion bodies morphologically consistent with polyomavirus in the lungs. Other available tissues from both cases were PyV-PCR-negative; however, both individuals tested positive for Guiana dolphin morbillivirus. To our knowledge, this is the first report of PyV infection in cetaceans of the Southern Hemisphere and the first description of a co-infection with morbillivirus.

Multi-targeted tyrosine kinase inhibitor QLNC-3A6 Di-maleate, a structurally novel small molecule compound, has therapeutic efficacy for the treatment of canine cutaneous mast cell tumor (CMCT) caused by mutations in the c-Kit gene. Since pharmacokinetic (PK) information plays an important role in the development and application of new drugs, etc., a rapid, highly sensitive and selective UHPLC-MS/MS analytical method was developed and validated for the first time in this study for the quantitative detection of QLNC-3A6 in canine plasma. 100 µL of plasma was precipitated using 350 µL of acetonitrile, and Chromatographic separation was performed on a Phenomenex Kinetex C18 column (50 × 2.1 mm, 2.6 µm) at a flow rate of 0.4 mL/min, the mobile phases were set to 0.1% formic acid aqueous solution (A) and 0.1% formic acid acetonitrile (B). The calibration curve linear range was 0.5-100 ng/mL (R²>0.99). The intraday and interday precision values (relative standard deviation, RSD) were 2.06-13.57% and 6.90-9.14%. Intraday and interday accuracies were -10.73 to 9.54% and -3.86 to 0.70% respectively. The dilution integrity RSD value and stability RSD value were less than 3.77 and 7.45%, respectively. Subsequently, the pharmacokinetics were investigated in canine after oral administration of QLNC-3A6 Di-maleate tablets at a dose of 3 mg/kg BW using this method. The results showed that QLNC-3A6 showed fast absorption rate, rapid distribution and slow metabolic elimination in canine plasma. The results of the main PK parameters including λz, T_1/2λz, C_max, T_max and AUC_last were 0.07 ± 0.01/h, 11.00 ± 2.57 h, 50.88 ± 31.94 ng/mL, 9.08 ± 11.57 h and 836.48 ± 230.53 ng h/mL, respectively.

Bovine respiratory disease (BRD) represents a significant challenge in cattle management due to its multifactorial nature and lack of a gold standard diagnostic method. Procalcitonin (PCT) has emerged as a potential biomarker for bacterial infections in various species, including cattle. This study aimed to investigate plasma PCT concentration variations in pre-weaned dairy calves categorized as BRD-positive using clinical scores (WRSC; BRD-positive ≥5), thoracic ultrasonography with two cut-off (TUS; BRD-positive ≥1 or ≥3), or a combination of both methods (WRSC/TUS1cm or WRSC/TUS3cm). Additionally, the accuracy of PCT in diagnosing BRD was evaluated. A cross-sectional study was conducted on a convenience sample of 226 pre-weaned Italian-Friesian female calves. Clinical scoring, TUS, and plasma PCT analysis were performed. Calves were categorized based on TUS findings, clinical scores, or a combination of both methods. Statistical analyses were conducted to assess the differences in PCT concentrations among different groups and to determine the diagnostic accuracy of PCT. Results showed a significant increase in PCT levels in calves with lung consolidation detected by TUS using a 1 cm cutoff. However, the diagnostic accuracy of PCT in discriminating BRD-positive cases was poor (area under the curve 0.62). The optimal cutoff value for PCT was determined to be 86.63 pg/mL, with sensitivity of 49.7%, specificity of 71.8%, positive predictive value of 79.4% and negative predictive value of 39.5%. In conclusion, while PCT showed potential as a biomarker for BRD, its diagnostic accuracy was limited in this study. Future research should focus on integrating PCT measurements with other diagnostic methods and conducting longitudinal cohort studies to better understand its role in BRD diagnosis and management.

Podolian cattle is an autochthonous breed well adapted to the harsh semi-arid environments of the Southern Italy regions; the extensive rearing system used for these indigenous animals is based on grazing on spontaneous pastures, such as grasslands or wood pastures These grazing systems respect animal welfare and enrich animal products with characteristics closely related to the feeding system and the farming environment. The aim of the present study was to characterize the nutritional value of a forage crop and a wood-pasture and to evaluate the effects of grazing by Podolian young bulls on the performances and meat quality in relation to the age at slaughter (14 or 18 months) and to the ageing time of meat (3, 9 or 14 days). The metabolizable energy and the gas production were greater in April and June for both pasture systems. Young bulls raised on the grassland showed greater slaughter weights (p < 0.05) as compared to those fed on the woodland system, at both the slaughtering ages. The Warner Bratzler Shear (WBS) force values for raw and cooked meat were not influenced by the pasture system but they significantly (p < 0.01) decreased in relation to the ageing time in all the groups. Ageing markedly (p < 0.05) increased the malondialdehyde (MDA) concentration from 3 to 14 days of storage, regardless of the pasture system and the slaughtering age. The n-6/n-3 polyunsaturated fatty acid ratio of meat was markedly lower in grassland animals, regardless of the age of slaughter. In conclusion, 18 months old grassland beef showed better performances and yield of meat cuts. Ageing for 9 days positively affected meat WBS without increasing MDA concentration.

Antibiotic-resistant pathogens are a growing global issue, leading to untreatable infectious diseases in both humans and animals. Personalized bacteriophage (phage) therapy, the use of specific anti-bacterial viruses, is currently a leading approach to combat antibiotic-resistant infections. The implementation of phage therapy has primarily been focused on humans, almost neglecting the impact of such infections on the health and welfare of companion animals. Pets also have the potential to spread resistant infections to their owners or the veterinary staff through zoonotic transmission. Here, we showcase personalized phage-antibiotic treatment of a cat with a multidrug-resistant Pseudomonas aeruginosa implant-associated infection post-arthrodesis surgery. The treatment encompassed a tailored combination of an anti-P. aeruginosa phage and ceftazidime, precisely matched to the pathogen. The phage was topically applied to the surgical wound while the antibiotic was administered intramuscularly. After two treatment courses spanning 7 and 3 weeks, the surgical wound, which had previously remained open for five months, fully closed. To the best of our knowledge, this is the first case of personalized phage therapy application in felines, which provides further evidence of the effectiveness of this approach. The successful outcome paves the way for personalized phage-antibiotic treatments against persistent infections therapy in veterinary practice.