Journal of Veterinary Medical Science最新文献

Detection of microorganisms from bovine using real-time PCR (Dembo PCR) is a comprehensive detection technique that was developed to detect pathogens causing bovine diseases. In Japan, the definitive tests for monitored infectious diseases, which are defined by law, are carried out at government agencies. On the other hand, the existence of pathogens other than monitored infectious diseases are not well understood. From the perspective of livestock quarantine, it is important to make it possible to identify pathogens other than monitored infectious diseases, so we extended the existing Dembo PCR system in this study. In particular, the number of targets other than monitored infectious disease was increased. The new version of Dembo PCR may be useful in elucidating new pathologies associated with multiple pathogens.

This study aimed to prospectively investigate the hypothesis that myocardial energy metabolism changes in the early stages of feline hypertrophic cardiomyopathy (HCM) by evaluating the blood carnitine profiles. Fourteen client owned cats with HCM stage B1 and 22 clinically healthy cats were included in this study. Total-carnitine, free-carnitine, acylcarnitine, and acylcarnitine/free-carnitine ratio (AF ratio) in serum were measured in both groups. No significant differences were observed in total-carnitine, free-carnitine, and acylcarnitine concentrations between the groups. However, the AF ratio in the HCM group was significantly lower than that of the control group (P=0.02). The lower serum AF ratio in cats with early-stage HCM, may suggest an alteration in their myocardial energy metabolism.

Protozoan parasites such as Eimeria tenella and Toxoplasma gondii pose significant health challenges in livestock and humans. The limited treatment options and rising drug resistance underscore the urgent need for new therapies. This study investigates myrcene, a monoterpene hydrocarbon classified for its antiprotozoal potential against E. tenella and T. gondii infections. Initially, we examined its effect on the sporulation process of E. tenella oocysts in vitro and its anti-E. tenella activity in vivo. Myrcene significantly reduced the sporulation rate of E. tenella oocysts at 3 and 4 mg/kg. In vivo experiments demonstrated that treatment with 4 mg/kg myrcene significantly reduced E. tenella load and oocyst output, as well as cecal lesion and weight loss caused by E. tenella infection, showing moderate anti-E. tenella activity, with an Anticoccidial Index (ACI) of 161.4. Furthermore, we investigated the anti-T. gondii activity of myrcene both in vitro and in vivo. In vitro studies showed that treatment with myrcene effectively inhibited the invasion rate and intracellular proliferation ability of T. gondii tachyzoite in DF-1 cells in a dose-dependent manner. In vivo administration prolonged the survival time in T. gondii-infected mice, suggesting notable protective effects. Additionally, it mitigated T. gondii-induced hepatosplenic toxicity by reducing parasite load in the liver and spleen, and ameliorating liver function as evidenced by decreased serum transaminase levels. In conclusion, the findings demonstrate promising anti-E. tenella and anti-T. gondii activity exhibited by myrcene warranting further exploration into its mechanisms and potential therapeutic applications.

Poultry red mites (PRMs, Dermanyssus gallinae), tropical fowl mites (TFMs, Ornithonyssus bursa), and northern fowl mites (NFMs, Ornithonyssus sylviarum) are hematophagous mites that are distributed worldwide which pose a serious challenge to the poultry industry and negatively impact poultry production and welfare. Vaccines represent a promising approach for controlling avian mites, and the identification of antigens with broad efficacy against multiple avian mite species is advantageous for vaccine control. This study aimed to identify histamine release factor (HRF), which was previously reported as a candidate vaccine antigen against PRMs, from TFMs and NFMs and to analyze its cross-reactivity and acaricidal effects on different avian mite species. The deduced amino acid sequences of the HRFs identified in the TFMs and NFMs were highly homologous to those of the PRMs. We generated recombinant HRF (rHRF) of TFMs, NFMs, and PRMs, and immune plasma against each rHRF was produced by immunization with each antigen. The immune plasma contained antibodies specific to each antigen and showed cross-reactivity with rHRFs from different avian mites. Moreover, PRM nymphs (protonymphs) artificially fed each immune plasma showed higher mortality rates than those fed the control plasma. These results suggest that HRFs can be used as candidate antigens for a universal vaccine with broad efficacy across avian mites.

Congenital cystic eye (CCE) is a rare congenital ocular disease, which has been suggested to be caused by problems with optic vesicle invagination. This is characterized by the formation of intraorbital cystic lesions lined by undifferentiated neuroepithelium. However, cases involving ocular structures with varying degrees of differentiation have also been reported as CCE in humans and animals. In horses, CCE have only been reported as a case presenting as neuroepithelial-lined cysts without the formation of ocular structures. This paper describes large bilateral intraorbital cysts in a 1-day-old horse. The histopathological findings revealed that the cysts were covered by neuroepithelium with formation of the lens, ciliary body, and optic nerve, and it was diagnosed as CCE. This report provides further variations of CCE in horses.

Piroplasmas (Babesia and Theileria) are protozoa transmitted from ticks to warm-blooded animals. Some species of them, such as Babesia microti, can cause zoonotic infections. Although B. microti infections in wild rodents and ticks in Japan have been frequently reported in Hokkaido, there are only older reports of zoonotic babesiosis in other areas of Japan. In this study, we investigated prevalence of piroplasma species in wild rodents and ticks collected in near Gifu City, a central region in Japan, between 2021 and 2023 using nested-PCR to detect the 18S rRNA gene sequences of various piroplasma species. Among 87 wild rodents, piroplasma gene sequences detected in four large Japanese field mice (Apodemus speciosus) were 100% identical to B. microti Otsu/Hobetsu type. Notably, the gene detected in one pool of nymphal Haemaphysalis ticks was closely related to Babesiamotasi-like isolates recently detected in human patients in South Korea. Additionally, the deer Theileria species, which has been widely detected throughout Asia, including Japan, was detected from Haemapyhsalis ticks. Our results indicate that a variety of piroplasmas, including piroplasmas that are potentially pathogenic to humans, such as B. microti Otsu/Hobetsu types and protozoa closely related to B. motasi, are distributed in the Gifu City area.

A homozygous calf with CACNA1S-related muscle weakness, a new autosomal recessive congenital disorder in Holstein cattle, was identified by genotyping 195 stored blood samples from Holstein calves aged less than 12 months. The patient was an 8-day-old male calf with congenital astasia which presented to a university hospital in 2019. The patient was unable to maintain an upright position with assistance to stand. Congenital abnormalities in the central nervous system were suspected, but necropsy revealed no specific lesion, with no clear diagnosis. CACNA1S-related muscle weakness should be considered a cause of congenital astasia or weakness in calves. Genotyping is required for a definitive diagnosis because clinical and laboratory findings are non-specific.

African swine fever (ASF) is a contagious hemorrhagic disease affecting both domestic and wild pigs with high mortality rate and severe socio-economic losses. Due to the virus' potential ability to remain infectious in suitable conditions and environments, it is imperative to identify risk factors that may contribute to its transmission. The Philippines' current ASF surveillance relies on pig blood samples. With this very limited epidemiological data, it is imperative to include raw meat and processed pork products due to high ASF transmission risks. In this study, a total of 384 raw pork and 384 processed pork products from selected wet markets were collected and detected the ASF virus (ASFv) VP72 gene using real-time polymerase chain reaction (rt-PCR), and the overall positivity rates were 10.16% and 10.68%, respectively. Moreover, an interview with wet market vendors was conducted, and the Least Absolute Shrinkage and Selection Operator (LASSO) regression was employed to identify possible factors associated with sample positivity. Results showed that ASFv-positive samples were linked to zoning status, rainy seasons, Longganisa preparation, selling different meat types, longer pork batches, and cleaning or disinfection in market stalls. Overall, ASFv contamination in pork and processed pork products can pose a threat to the swine industry, and market practices may further lead to ASFv persistence in these commodities which may contribute to ASF spread. Therefore, there's a need to address this risk by strict surveillance and proper handling procedures throughout the food supply chain.

In Egypt, camel trypanosomiasis is widespread. From October 2021 to March 2022, we collected 181 blood samples from apparently healthy one-humped camels (Camelus dromedarius) in Cairo and Giza Governates. The objective of this study was to assess infection rates of trypanosomes using blood smear examination and PCR-sequencing assays. Trypanosomes were detected in 8.3% (15/181) of camels by blood smear and in 23.8% (43/181) by PCR targeting the internal transcribed spacer (ITS). Based on blood smear and ITS-PCR results, and the absence of tsetse flies in the study area, we hypothesized that the Trypanosoma species was likely T. evansi. Validation using PCR based on the variant surface glycoprotein (VSG) of T. evansi Rode Trypanozoon antigen type (RoTat) 1.2 (RoTat 1.2 VSG gene) on ITS-PCR-positive samples (n=43) confirmed that 88.4% (38/43) were RoTat 1.2 T. evansi, while 11.6% (5/43) were non-RoTat 1.2 T. evansi. This marks the second report of non-RoTat 1.2 T. evansi in dromedary camels in Egypt. Considering the underestimated zoonotic risk of T. evansi in Egypt, there is a potential threat to humans, underscoring the need for a "One Health" approach to safeguard animal and human health.

Cerebrospinal fluid (CSF) circulation diseases, such as hydrocephalus and syringomyelia, are common in small-breed dogs. In human patients with CSF circulation diseases, time-spatial labeling inversion pulse (time-SLIP) sequence performed to evaluate CSF flow before and after treatment allows visualization of the restoration of CSF movement. However, studies evaluating CSF flow using the time-SLIP method in small-breed dogs are limited. Therefore, the present study aimed to evaluate intracranial CSF flow on time-SLIP images in small-breed dogs with idiopathic epilepsy, as an alternative model to healthy dogs. Time-SLIP images were obtained at two sites: 1) the mesencephalic aqueduct (MA) area (third ventricle, MA, and brain-base subarachnoid space [SAS]) and 2) the craniocervical junction area (fourth ventricle, brainstem, and cervical spinal cord SAS) to allow subsequent evaluation of the rostral and caudal CSF flow using subjective and objective methods. In total, six dogs were included. Caudal flow at the MA and brain-base SAS and rostral flow in the brainstem SAS were subjectively and objectively observed in all and 5/6 dogs, respectively. Objective evaluation revealed that a significantly smaller movement of the CSF, assessed as the absence of CSF flow by subjective evaluation, could be detected in some areas. In small-breed dogs, the MA, brain-base, and brainstem SAS would be appropriate areas for evaluating CSF movement, either in the rostral or caudal flows on time-SLIP images. In areas where CSF movement cannot detected by subjective methods, an objective evaluation should be conducted.