Journal of Veterinary Diagnostic Investigation最新文献

A subcutaneous tumor was identified in the lateral neck of a wild adult serotine bat (Eptesicus serotinus). Histologic examination revealed a non-encapsulated, poorly demarcated, densely cellular and infiltrative round-cell neoplasm, with cytonuclear atypia and a high mitotic count. Neoplastic cells had numerous Giemsa-positive metachromatic intracytoplasmic granules leading to a diagnosis of subcutaneous mast cell tumor (MCT). Immunohistochemical analysis demonstrated positive staining for KIT with a diffuse cytoplasmic pattern, confirming the mastocytic origin. The tumor had histologic features suggestive of malignant behavior, which was confirmed by the metastatic mast cells in the regional lymph node adjacent to the tumor. MCT has not been reported previously in a chiropteran species, to our knowledge. Based on this case, MCTs in this species have malignant potential, and their diagnosis may require additional stains and immunohistochemistry (IHC). Our results support further investigation regarding the utility and prognostic value of KIT IHC in bats in this context.

Fibrolipoma is a well-recognized benign neoplasm composed of adipocytes transected by fibrous connective tissue, but large population studies on these neoplasms are lacking in veterinary medicine. We retrospectively searched for canine cutaneous and subcutaneous fibrolipomas submitted to the surgical diagnostic pathology service of the Athens Veterinary Diagnostic Laboratory (Athens, GA, USA) between 2017 and 2024. We retrieved 236 neoplasms from 64,560 biopsies. The median age of affected patients was 8 y (±2.8 y), with an average tumor size of 2.9 cm (±2.3 cm). The head was the location affected most commonly (31.9% of cases), followed by the carpal area (10.3%), elbow (9.9%), thorax (6.9%), and abdominal wall (5.6%). Most cases were classified as cutaneous (90%). Compared with the total number of biopsy submissions, castrated male (46.2%; p = 0.013) and Labrador Retriever (23%; p = 0.047) dogs were affected most often.

Domestic cat hepadnavirus (DCHBV; Hepadnaviridae, Orthohepadnavirus felisdomestici) is a hepadnavirus identified in domestic cats that is associated with liver conditions that resemble hepatitis B virus (HBV) infections in humans. Despite its significance for feline health, research on DCHBV has been hindered due to the absence of suitable in vitro models, particularly the lack of feline hepatocyte cell lines. We found that cells of the human-derived hepatoma cell line, HepG2, were susceptible to DCHBV infection. DCHBV DNA and RNA were detected from the infected HepG2 cells at 48 h postinfection; DCHBV core protein and viral particles were detected within the infected cells. No significant enhancement of viral infection was observed by the addition of dimethyl sulfoxide or dexamethasone to the culture medium. However, higher levels of viral uptake were noted at 4 d postinfection when using a concentrated viral inoculum. Although HepG2 cells supported initial DCHBV infection, viral load declined over time during serial infection experiments. The DCHBV infection of HepG2 cells is limited and declines over successive passages, potentially due to insufficient cellular factors for sustained viral replication. Our findings establish a foundation for further investigations of DCHBV biology and highlight the necessity for identifying alternative cell lines to improve long-term infection models.

A 17-wk-old male Rottweiler puppy was found dead 2 d after being presented with coughing and lethargy. Gross and histopathologic findings were consistent with fibrinosuppurative bronchopneumonia, and Pasteurella canis was isolated on culture of the lung. Mycoplasma cynos was identified by PCR testing of the lung in this case and may have contributed to the development of the pneumonia. P. canis is not a commonly recognized cause of canine bronchopneumonia but likely has a role in the canine respiratory disease complex. P canis is a known cause of pneumonia in other species with similar histologic findings, including humans.

Congenital neoplasms are rare and sporadic in cattle and can cause losses due to abortions and perinatal or neonatal deaths. The etiopathogenesis of congenital tumors in bovine fetuses and neonates is largely unknown, and their diagnosis is often challenging. Here we review the literature on congenital tumors in cattle and report 11 additional cases diagnosed at veterinary diagnostic laboratories in Argentina, Uruguay, the United States, and the United Kingdom, namely 4 congenital lymphomas, 3 mesotheliomas, 2 adenomatoid tumors, 1 lymphangioma, and 1 ovarian sex cord-stromal tumor in bovine fetuses and/or neonatal calves. Lymphomas, mesotheliomas, melanomas, and mast cell tumors were reported most commonly in the literature.

Two captive 19-y-old green tree pythons (Morelia viridis), a male and a female, were diagnosed with lymphoma. At autopsy, the female was in poor body condition and had an extensive subcutaneous soft tissue mass along the ribs. The mass was composed of numerous neoplastic round cells that were also present in the liver and spleen and within blood vessels. Neoplastic cells had marked, diffuse membranous-to-cytoplasmic immunolabeling for CD3, consistent with disseminated leukemic T-cell lymphoma. The male had a history of chronic spinal deformities and was in poor body condition. All examined organs contained variable numbers of neoplastic round cells with moderate-to-marked nuclear-to-cytoplasmic immunolabeling for PAX5, consistent with B-cell lymphoma. Here we describe 2 distinct immunophenotypes of lymphomas, including a B-cell neoplasm that has not been reported previously in snakes, to our knowledge. Our 2 cases highlight the potential value of CD3 and PAX5 immunohistochemical markers in ophidians and expand the spectrum of neoplastic diseases documented in reptiles. Understanding the clinical significance of lymphoma in snakes, including its potential impact on prognosis and challenges in management, is critical to refining therapeutic approaches in captive reptile care.

A large renal mass was identified by ultrasound during a regular health check on an intact adult female chimpanzee (Pan troglodytes). Cytology revealed a neoplastic population of clusters of polygonal cells with distinctive pink, granular cytoplasm. The primary differentials were oncocytoma and renal chromophobe cell carcinoma. The mass was surgically resected and grossly it effaced >75% of the right kidney and had a central scar. Histology confirmed an oncocytoma based on characteristic morphology, diffuse expression of cKIT (CD117), and limited expression of CK7, both assessed via immunohistochemistry. Transmission electron microscopy identified the granular component of the cytoplasm as mitochondria. Renal oncocytoma has not been reported previously in a great ape, to our knowledge. Our case appears nearly identical to the frequently reported and well-characterized human counterpart.

Gill neoplasia in fish is rare but has been reported in multiple elasmobranch and teleost species. Although more commonly a site of metastatic disease, primary neoplasms of the gill may occur, and both spontaneous and chemically induced tumors have been reported. Here we describe a spontaneous branchioblastoma in a koi carp (Cyprinus rubrofuscus) with no known history of chemical exposure. A soft-tissue mass on the inner surface of the dorsal opercular chamber appeared to originate from either a gill arch or a pseudobranch. Histologically, the mass was comprised of 3 well-differentiated cell types: blastemal cells, epithelial cells arranged in a lamellar fashion, and islands of cartilage resembling those present in gill filaments. To our knowledge, this is only the fourth case of spontaneous branchioblastoma recorded in koi.

Bovine anaplasmosis, caused by the rickettsia Anaplasma marginale, is an economically important tick-borne disease of cattle that is found worldwide. Its clinical effects of severe anemia, decreased growth, weight loss, and death negatively impact cattle welfare and create a significant economic burden for cattle producers. Despite availability of highly sensitive and specific assays for anti-A. marginale antibodies (competitive ELISA) and A. marginale genetic material (real-time PCR), the interpretation of test results for the diagnosis of clinical anaplasmosis in cattle remains challenging. Treatment and control usually consist of administration of oral and/or injectable tetracyclines; however, this approach is unlikely to be sustainable in the face of increasing scrutiny of antimicrobial usage in livestock. Statistically robust prospective studies are needed to characterize the prevalence, distribution, and transmission of bovine anaplasmosis under field conditions, as the epidemiology of this disease remains incompletely understood. Apart from minimizing exposure of naïve cattle to carriers (e.g., testing new introductions and interpreting in the context of herd-level seropositivity, changing needles between cattle), veterinarians and producers have few tools for prevention of bovine anaplasmosis based on data-driven risk assessment. A vaccine that is consistently safe and effective has proved elusive, but ongoing research into A. marginale vaccine candidates offers hope for a more effective means of protecting cattle from this costly disease.

Toxoplasma gondii is a widespread intracellular protozoan that can infect humans and animals. We isolated T. gondii strains from sheep, goats, cattle, buffaloes, and camels to develop and evaluate a modified in-house dot-ELISA for the detection of Toxoplasma antibodies in farm animals, and compared the results with a commercial ELISA (IDvet; gold standard). Animal tissue samples (n = 430) were examined microscopically, and infected tissues were bioassayed in mice as a viability test. Egyptian Toxoplasma strains were isolated from sheep, cattle, and camels and identified via PCR using the B1 gene (GenBank OR837022.1, OR837021.1, OR837020.1 from sheep, cattle, and camels, respectively). A T. gondii tachyzoite antigen from a sheep strain had the highest potential for the detection of specific T. gondii antibodies. We characterized this antigen using SDS-PAGE and separated it into 10 polypeptides of 96-12 kDa. Our modified in-house dot-ELISA detected T. gondii seropositivity in 172 of 430 (40%) farm animals with a sensitivity of 96.6% and specificity of 100%. The results of our dot-ELISA were confirmed in comparison with those of our indirect ELISA and the commercial ELISA. In a western blot, a predominant immunogenic reactive antigen band of 65 kDa was detected in T. gondii-positive sera of sheep, cattle, buffaloes, and camels; no cross-reaction occurred with antibodies to other parasitic infections or samples from healthy controls. Our modified in-house dot-ELISA is a rapid and simple test that showed promise for the detection of Toxoplasma antibodies in farm animals.