Listeriosis is a disease that affects several animal species, including humans, and has three different forms of presentation: encephalic, reproductive, or septicemic. The nervous form is caused mainly by the bacterium Listeria monocytogenes. In Brazil, this disease has already been described in sheep, goats, and cattle. There are no reports of the disease in buffaloes in Brazil and worldwide. The objective of this study was to describe an outbreak of listeric meningoencephalitis in buffaloes in the state of Pará, Brazil. The outbreak occurred in a property located in the municipality of Bujaru, in the eastern Amazon, from May to July 2016. In a herd of 47 buffaloes, three animals (Cases 1, 2 and 3), aged <40 days, presented a neurological condition with locomotion difficulty characterized by paralysis of the four limbs, hypoesthesia, lateral recumbency, and death. Morbidity was 6.38% and lethality was 100%. At necropsy, no significant macroscopic lesions were found. Samples of the central nervous system were collected, fixed in 10% buffered formalin, and routinely processed for histopathological analysis. The main microscopic changes observed were unilateral microabscesses in the brainstem composed predominantly of mononuclear cells, with fewer polymorphonuclear cells, and perivascular cuffs composed mostly of mononuclear cells and few neutrophils. Samples of Cases 1 and 2 revealed Gram-positive bacteria in the areas of necrosis by the Gram’s stain technique. Samples of Case 1 were positive in immunohistochemistry for L. monocytogenes. Diagnosis of the nervous form of listeriosis was based on epidemiological data, clinical profile, and immunostaining for Listeria monocytogenes. Results showed that listeriosis should be considered in the differential diagnosis in buffaloes with nervous signs.

Two outbreaks of trypanosomiasis by

Background: Transmissible venereal tumor (TVT) is a highly contagious round cell neoplasm that affects dogs, and it is usually transmitted through coitus. The tumor is mainly located in the genital area; however, the neoplasm can also be extragenital, affecting the nose, mouth, and eyes, as well as the skin and superficial lymph nodes. Cytological examination is the most commonly used method for definitive diagnosis due to its low cost and fast execution. Chemotherapy, radiotherapy, surgical resection, and other procedures such as cryosurgery are the possible treatment options. The objective of this report was to describe a case of extragenital TVT with nasal primary site and metastasis in the bone tissue in a dog treated at a private veterinary hospital in the city of Belém, Pará, Brazil.Case: A 6-year-old male domiciliary Labrador Retriever dog, weighing 24.2 kg, received oncologic treatment in a private veterinary hospital in the city of Belém, Pará, Brazil. The animal had a history of neoplastic disease, and he had undergone TVT resection associated with chemotherapy treatment more than 3 years ago. The clinical examination revealed a volume increase in the periorbital region, left lateral ocular displacement, left nostril excessive epistaxis, recurrent sneezing, cough, and pain signs, and tumor metastasis was suspected. Complementary exams of oncological cytology, computed tomography (CT), hemogram, and serum biochemistry were requested for diagnosis and staging of the condition, and supportive therapy was prescribed. The cytological report showed a dense population of neoplastic round cells with characteristics of TVT. CT indicated the presence of a heterogeneous hypodense mass with irregular contours and partially defined limits, with slight uptake of the intravenously injected contrast medium that obliterated the nasal cavity, maxillary recess, nasopharyngeal meatus, frontal sinus, and sphenoid sinus on the left side. The hematological analysis revealed mild anemia, neutrophilia, and lymphopenia, while the biochemical analysis only showed hypocalcemia. The prescribed therapy was amoxicillin + potassium clavulanate, omega-3, firocoxib, tranexamic acid, and finally chemotherapy with lomustine. Since the patient did not return for follow-up, the outcome could not be determined.Discussion: The patient described in this report was a domiciliary dog who did not live with other pets, but had access to the community environment and contact with other animals. The animal’s history, clinical signs, and cytological and imaging findings were consistent with those of TVT. In extragenital presentations of TVT, the inguinal and sublumbar lymph nodes, lungs, and abdominal organs are most commonly affected. Furthermore, bone involvement is rare, as this has not been commonly described in the literature as compared to the other sites of metastases. An abrasive brush was used for the cytological sample collection, because it provides slides with richer cells as compared to the imprint samples. CT is an important tool for the diagnosis of neoformations in the skeleton, and this method demonstrated high efficiency in identifying the bone involvement and the degree of the invasion and lesion in this case. The therapeutic agents used in this case were different from the usual, since the patient was given lomustine (40 mg/capsule, orally) in the metronomic chemotherapy. This drug has been previously used as an alternative in a canine TVT case resistant to vincristine.Keywords: neoplasm, extragenital, computed tomography, TVT.Título: Tumor Venéreo Transmissível (TVT) nasal com metástase óssea em um cãoDescritores: neoplasia, extragenital, tomografia computadorizada, TVT.

Domestic buffalo production plays an economically important role in the Brazilian Amazon, but they are susceptible to many diseases favored by the tropical climate and annually flooded habitats, including ocular diseases. In this context, it is important to select genotypes that maximize innate ocular immunity in Amazonian herds. We aimed to characterise, for the first time, gene expression profiles of the innate immune system in the conjunctival membrane of buffalo. Ocular conjunctival tissue samples were collected from 60 clinically healthy slaughtered animals in the northern Brazilian state of Amapá. The samples were histologically processed for classification into three groups according to the quantitative degree of lymphoid tissue associated with the conjunctiva (discrete, G1; slight, G2; and moderate, G3 presence of lymphoid tissue). RT-PCR was used to quantify gene expression of inflammatory cytokine (IL6, IL10, TNFA, IFNG), Toll-like receptor 4 (TLR4), and Defensin beta 110 (DEFB110), relative to the endogenous GAPDH gene. G1 animals presented low expression for IL6, IL10, TNFA, and DEFB110, while G2 exhibited high expression for IL6, IL10, IFNG, and TLR4. All G3 animals showed high expression for all tested genes. These results suggest a greater resistance to pathogenic microorganisms of buffalos in the G3 group, and the proportion of lymphoid tissue associated with the conjunctiva may be related to the immune resistance of individuals.

Background:Intestinal neoplasms are uncommon in dogs and adenocarcinoma is the main histological type found. This neoplasm presents slow growth and high capacity of causing metastasis. Histologically speaking, neoplasm cells can present solid, tubular, papillary arrangement and note amorphous extra-cellular material. Clinically observed tenesmus, diarrhea, dyskinesia, hematochezia, mane, protrusion of the anus, weight loss, anorexia. The occurrence and clinicopathological aspects of tumors in dogs' gastrointestinal tract, the rectal segment, remains poorly understood. Accordingly, the aim of the present study is to report a case on infiltrative rectal adenocarcinoma diagnosed in a dog. Case: A 7-year-old male dog representative of the Fila Brasileiro breed was presented to the Veterinary Hospital of University Federal Rural of Amazonia, with history of hyperthermia, anorexia, apathy and tenesmus. Imaging examinations depicted prostatomegaly. Exploratory laparotomy was performed and showed the thickening and hardening of the rectum segment. The animal was subjected to euthanasia. Necroscopy showed increased rectal perimeter; the mucosa in its opening presented atypical cerebroid aspect and irregular surface, and areas dark red. The rectal segment depicted a thick wall of white color, irregular limits covering the muscular and adjacent sub-mucosa. The peri-rectal adipose tissue presented poor delimitation with the rectum, multiple greyish and reddish areas. Increased prostate and iliac lymph, and multi node of regular limits in the lungs. The histology of the rectal tissue depicted epithelium with differentiated neoformation, composed of atypical cells; nuclear anisocytosis, anisocariasis and hyperchromasia placed in small islands, cords or tubular formation. Neoplasm growth was unorganized and of infiltrative character. Some areas presented mucosal pattern cells with Signal Ring morphologic. Multiple rectal blood vessels, regional lymph nodes and lungs had neoplasm growth similar to that observed in the intestine. Mucosa also presented ulceration areas and lymphoplasmacytic infiltrate. There was fibroplasia, lymphoplasmacytic points and bleeding in the serous, as well as in the peri-rectal fat tissue. The immunohistochemical technique showed immunostaining in cytokeratin and vimentin antibodies, and in marked epithelial cells and tumor stroma markings, respectively. Discussion: The intestinal tumor diagnosis in dogs is found by associating history, clinical signs, radiographic, ultrasound findings and necropsty. Only one data about the occurrence of rectal adenocarcinoma in Fila Brasileiro specimens. With regards to sex, results were similar to those record, whose males presented higher prevalence of primary rectal tumors. The macroscopic characteristic is consistent with infiltrative neoplasms; thickening was related to the presence of the tumor. The histopathological findings evidenced growing infiltrative neoplasm formed by atypical cells of tubular arrangement. Microscopy featured a chronic ulcerative colitis ...