Veterinary Research Communications最新文献

This study aimed to determine whether urinary pH can be used to predict metabolic acidosis in sheep with acute rumen lactic acidosis (ALRA). ALRA was induced by administering sucrose intraruminally to 40 apparently healthy sheep. Venous blood and urine samples were collected before induction (‒18 h) and prior to treatment (0 h) to measure blood pH, base excess (BE), and urinary pH. Associations between urinary and blood pH, and between urinary pH and BE, were examined using Pearson correlation and linear regression. Blood and urinary pH were positively correlated (r = 0.633; P < 0.001), as were BE and urinary pH (r = 0.602; P < 0.001). The regression coefficients were r² = 0.401 and r² = 0.362, respectively, and the relationships were described by the following equations: pH = (urinary pH × 0.063) + 6.909; BE = (urinary pH × 3.66) ‒ 30.512. Calculated values of blood pH and BE did not differ from measured values ​​(7.346 ± 0.072 vs. 7.346 ± 0.114; P = 0.979; and ‒5.11 ± 4.21 mmol/L vs. ‒5.11 ± 6.99 mmol/L; P = 0.998, respectively). When used as a diagnostic criterion for metabolic acidosis, the BE calculated from urinary pH demonstrated a sensitivity of 81.8%, specificity of 82.5%, negative predictive value of 84.6%, positive predictive value of 79.4%, and accuracy of 82.2%. These findings indicate that urinary pH can be used as a practical predictor of metabolic acidosis in sheep with ALRA.

In an era of antimicrobial resistance (AMR), identifying alternatives to conventional antibiotics in livestock farming is vital for veterinary medicine and public health. Due to the constant exposure to pathogens and the need for optimal productivity, maintaining gut homeostasis is essential in poultry. Therefore, investigating antimicrobial alternatives that can support gut health is of key importance. Host defense peptides (HDPs) have been identified as promising candidates due to their beneficial effects on the gut; however, there is still much to clarify regarding the individual peptides' mechanism of action. In the present study, the HDP cecropin A (CecA) was applied to chicken-derived ex vivo ileal explant cultures to examine its impact on immune response and tight junction (TJ) protein expression. CecA was applied at 3.125 and 6.25 µg/mL concentrations, either alone (Cec-low and Cec-high) or in polyinosinic-polycytidylic acid (Poly I:C, 50 µg/mL)-induced inflammatory conditions (PI:C + Cec-low and PI:C + Cec-high). The experiment revealed that CecA had no impact on cell viability, as reflected by unchanged metabolic activity and extracellular lactate dehydrogenase activity. Regarding the immune state, Cec-high and PI:C + Cec-high increased the production of interleukin (IL)-2, whereas IL-6 concentration was decreased by PI:C + Cec-low treatment. Furthermore, Cec-high elevated the intracellular expression of the TJ protein claudin-3. In conclusion, CecA displayed immunomodulatory activity in chicken intestinal cells and supported epithelial integrity without exerting cytotoxic effects.

Viral infections can cause increased mortality of honey bee colonies. Because of an asymptomatic course of infections their detection in honey bees is only possible by the use of sensitive and specific diagnostic methods. Nowadays, the conventional RT-PCR assays are routinely employed for detection of honey bee viruses, but none of them have had their diagnostic usefulness confirmed through documented optimization and validation process. The aim of this study was to develop of the two in-house multiplex RT-PCR (mRT-PCR) assays for the detection of CBPV, iflaviruses (DWV-A, SBV) and dicistroviruses (ABPV, IAPV, BQCV) of bees. The sequences of the primers used in the developed Ifla-CBPV and Dicistro mRT-PCRs were refined to include point mutations observed in the respective genome fragments of honey bee viruses detected worldwide so far, including newly characterised virus strains from Poland. The optimization of the PCR mixtures composition and temperature-time profiles of the assays was performed. To avoid false negative results, an internal amplification control (IAC) was prepared and incorporated into the Ifla-CBPV and Dicistro mRT-PCR assays. The developed IAC-controlled mRT-PCR assays allow for simultaneous detection of mixed viral infections caused by six virus species commonly occurring in worldwide population of bees. The use of IAC during molecular detection enables monitoring of the assays correct performance.

Domesticated dogs used for hunting come into close contact with humans, domestic animals and wildlife, exposing them to ticks and tick-borne pathogens. It is crucial to include them in surveillance activities to monitor the spread of zoonotic pathogens and formulate effective preventive and control measures. This study sought to examine the diversity of tick species infesting hunting dogs and to detect the DNA of tick-borne pathogens they carry. Ticks were collected from 28 hunting dogs, morphologically identified using available taxonomic keys, and their identifications confirmed by molecular methods. Total nucleic acid was extracted from individual tick species and screened for pathogens using PCR and Sanger sequencing. A total of 142 ticks were identified, with Rhipicephalus sanguineus (85.94%) as the predominant species. This study reports the first molecular confirmation and report of Amblyomma sparsum, Haemaphysalis parva, Rhipicephalus leporis and Rhipicephalus linnaei in Ghana. Pathogen DNA was detected in 31 (21.83%) of the ticks, with the occurring pathogens as Hepatozoon canis (13.28%), Uncultured Anaplasma sp. (7.75%), Ehrlichia canis (7.04%), Rickettsia africae (1.41%) and Uncultured Rickettsia sp. (0.7%). The findings of this study indicate that hunting dogs can be useful sentinels in monitoring tick populations and the spillover of zoonotic tick-borne pathogens from wildlife to humans and domestic animals. This study highlights the need for education, surveillance, and tick control strategies in Ghanaian dog populations to reduce the threat of zoonotic disease establishment and transmission.

This study aimed to investigate the prevalence, antimicrobial resistance, biofilm-forming ability, virulence gene profiles, and associated risk levels of Enterococcus faecalis and E. faecium isolated along the farm-to-fork meat production continuum in Kayseri, Türkiye. Out of 348 samples analyzed, Enterococcus spp. were detected in 209 (60%) of the samples, of which 41 (20%) were E. faecalis and 48 (23%) were E. faecium. Both strains were resistant to at least one antimicrobial agent, and 35 isolates (39%) exhibited multidrug resistance (MDR). Among the tested antibiotics, resistance rates were particularly high for tetracycline (66% in E. faecalis, 69% in E. faecium) and erythromycin (56% and 58%, respectively); resistance to vancomycin (10% in each species) and ciprofloxacin (12% in E. faecalis and 13% in E. faecium) was low but consistently occurred in combination with resistance to other antibiotics and exclusively within multidrug resistance patterns. All isolates formed biofilms, with 55% being strong producers, of which 88% carried the gelE and/or efa gene. Strong biofilm formation was correlated with higher MDR rates (51% in strong biofilm producers and 25% in weak producers), peaking at 58% in E. faecalis strong producers. Risk scoring classified up to 40% of isolates as high risk. These findings suggest that enterococci may contribute to food contamination and serve as potential reservoirs of resistance and virulence, underscoring the relevance of farm-level hygiene, rational antibiotic use, and targeted surveillance within a One Health framework.

Echinococcus granulosus sensu stricto (G1 genotype), the predominant causative agent of zoonotic cystic echinococcosis, continues to jeopardize public health across the pastoral ecosystems of the Qinghai-Tibetan Plateau. Here, we provide a novel molecular genetic evidence from the Qinghai Lake by investigating hydatid cysts in two key livestock species sheep and yaks. Through an innovative dual-marker strategy targeting mitochondrial Cytochrome c oxidase subunit 1 (cox1) and NADH dehydrogenase subunit 1 (nad1) genes, we conducted PCR amplification and haplotype analysis, combined with maximum likelihood (ML)-based phylogenetic reconstruction and divergence time estimation. The results demonstrated that all 13 positive samples belonged to the Echinococcus granulosus genotype 1 of E. granulosus s. s. and reveal a pivotal Miocene-Pliocene divergence event (5.8 ± 0.5 million years ago) within Echinococcus spp., establishing critical evolutionary benchmarks. This study not only provides updated epidemiological data on echinococcosis in the Qinghai Lake, but more importantly, deliver critical molecular evidence for precision control of zoonotic diseases in high-altitude pastoral ecosystems.

Background: Burkholderia pseudomallei, the causative agent of melioidosis in humans and animals, has been implicated in acute infections with high mortality rates in animal hosts and in mastitis in dairy cattle. It has intrinsic resistance to a wide range of antibiotics and is also known to possess a multitude of virulence determinants. This study provides baseline data on the occurrence of this pathogen in bovine milk samples in Osogbo, Southwestern Nigeria.

Methods: A total of 371 milk samples collected from dairy cows with clinical and subclinical mastitis were assessed for the presence of B. pseudomallei using phenotypic microbiological techniques, confirmed by molecular methods. Selected resistance (folA, folP, Omp38, bpeE and bpeF) and virulence (bsaU, pili/fimbriae, bimA, tssA and wbiE) genes were screened for using self-designed specific primers, while antibiotic susceptibility testing against clinically relevant antibiotics was via the Kirby-Bauer disc diffusion technique.

Results: Molecular identification confirmed 16 isolates (4.31%) as B. pseudomallei. Resistance to amoxicillin-clavulanic acid, imipenem, tetracycline and ceftazidime was absolute (100.0%), trailed by trimethoprim-sulfamethoxazole (SXT) at 93.8%. Meropenem exhibited the highest activity in vitro, as 93.8% of isolates were susceptible to it. All isolates (100.0%) were classified as extremely drug-resistant (XDR), with multiple antibiotic resistance indices ≥ 0.2. All isolates (100.0%) also harboured both resistance and virulence determinants, with 68.8% having ≥ 6 genes - 93.75% had the folP gene. The predominant virulence gene was BsaU, detected in 87.5% of isolates. No isolates had the wbiE gene.

Conclusion: The presence of XDR strains and carriage of multiple resistance and virulence genes in B. pseudomallei strains portend serious implications in affected dairy cattle. This study recommends prudent antibiotic use in dairy cattle and the proper processing of milk before consumption to limit the risk of zoonotic transmission.

Over the years, Staphylococcus nepalensis has been reported in some species of wild and domestic animals, indicating a broad ecological distribution and has a significant impact on a variety of other species, from mammals to reptiles, which can serve as its environmental reservoir. In addition, concerns around human health endows a nosocomial importance. The aim was to report the isolation and identification of S. nepalensis in the oral cavity of Lampropeltis triangulum under human management in a zoological park. The single isolate was identified by MALDI-TOF and underwent Antimicrobial Susceptibility Testing (AST). The antimicrobial resistance profile tested for eleven different classes of drugs revealed a high rate of sensitivity. It is necessary to reinforce the importance of monitoring and controlling the use of antimicrobials in veterinary settings and wildlife management practices, thus preventing the spread of multidrug-resistant strains that could render therapeutic protocols ineffective and pose a risk to public health. This study expands the known host range of S. nepalensis and underscores the need for surveillance in reptile species.

To compare surgical time, incision length, intraoperative bleeding, and post-operative pain in cats undergoing three different ovariectomy techniques: open surgery with pedicle ligation using sutures, open surgery using a bipolar vessel-sealing device, and a two-port laparoscopic approach. A prospective randomized clinical trial was conducted on 27 healthy female cats assigned to three treatment groups (n = 9 per group). Surgical variables were recorded intraoperatively, and post-operative pain was assessed using a validated feline pain scale at hourly intervals over four hours. The laparoscopic group had the shortest incision length (mean 10.0 mm, SD 0.0) compared to the suture (mean 33.3 mm, SD 5.6) and bipolar device groups (mean 28.7 mm, SD 6.4). Surgical time was significantly shorter in the BVSD (27.0 ± 9.6 min) and LOVE groups (30.2 ± 5.2 min) compared with the Suture group (43.9 ± 14.4 min; one-way ANOVA, p = 0.005; Tukey post-hoc p < 0.05 vs. Suture for both comparisons). Post-operative pain scores at one hour (T1) were lower in the LOVE group (median 4 [IQR 3-5]) than in both open groups (Suture: 9 [IQR 8-9]; BVSD: 7 [IQR 6-8]; Kruskal-Wallis, p = 0.014; Dunn's post-hoc p < 0.05 vs. BVSD and trend towards lower scores vs. Suture). Only 1 of 9 cats requiring rescue analgesia versus 7 of 9 in each open group. The laparoscopic approach was associated with lower post-operative pain scores and a reduced need for rescue analgesia compared to open ovariectomy techniques, suggesting improved perioperative comfort. Although the laparoscopic group showed a significantly shorter surgical time compared with the suture group, this observation should be interpreted cautiously due to potential operator- and case-dependent variability. Nevertheless, laparoscopic ovariectomy in cats should be considered a promising and welfare-oriented technique that warrants further investigation.