Haemophilus parasuis is the causative agent of the Glässer’s disease (GD), one of the most important bacterial diseases that affect young pigs worldwide. GD prevention based on vaccination is a major concern due to the limited cross-protection conferred by the inactivated whole cell vaccines used currently. In this study, vaccines based on two mutant recombinant proteins derived from transferrin binding protein B of H. parasuis (Y167A-TbpB and W176A-TbpB) were formulated and evaluated in terms of protection against lethal challenge using a serovar 7 (SV7) H. parasuis in a high susceptibility pig model. Our results showed that H. parasuis strain 174 (SV7) is highly virulent in conventional and colostrum-deprived pigs. The Y167A-TbpB and W176A-TbpB antigens were immunogenic in pigs, however, differences in terms of antigenicity and functional immune response were observed. In regard to protection, animals immunized with Y167A-TbpB antigen displayed 80% survival whereas the W176A-TbpB protein was not protective. In conjunction with previous studies, our results demonstrate, (a) the importance of testing engineered antigens in an in vivo pig challenge model, and, (b) that the Y167A-TbpB antigen is a promising antigen for developing a broad-spectrum vaccine against H. parasuis infection.

Parasitic myelopathy caused by Gurltia paralysans in domestic cats is a disease commonly reported in several South American countries. The adult parasite is lodged in the meningeal veins and spinal cord, often causing clinical manifestations of vascular proliferation, thrombophlebitis, and medullary compression. Wild felines are believed to be the definitive hosts of this parasite. The infection occurs through the ingestion of paratenic hosts, but the life cycle of G. paralysans is not yet clearly understood. In this paper, we discuss a case of parasitic myelopathy in a margay (Leopardus wiedii) that died during post-surgical care. Necropsy revealed focal hemorrhages in the thoracolumbar spinal cord. A microscopic examination revealed adult nematodes and eggs inside the veins of subarachnoid space in spinal cord, suggesting G. paralysans infection. This is first description of parasitic myelopathy in a margay in Brazil.

Glaesserella parasuis is a Gram-negative bacterium that causes Glässer's disease, a common pathology found in young pigs characterized by polyarthritis, polyserositis, and meningitis. The bacterium has 15 known serovars that have been classified by virulence. Serovars 1, 4, 5, and 12 are considered highly virulent and used in most studies. Serovars 3, 6, 7, 9, and 11 are considered avirulent. Recent reports that serovar 7 is an emerging problem in the pig industry indicate that the association of virulence and serovar may not always be reliable. This led us to infect colostrum-deprived piglets with the reference serovar 7 strain (SV7 strain 174) that had been passaged through pigs and characterize the clinical and pathological signs. We observed that SV7 strain 174 caused clinical signs consistent with Glässer's disease in all infected piglets that succumbed to infection for up to day 5 post-infection. Macroscopic and microscopic lesions were consistent with those found in piglets infected with conventional virulent serovars. In addition, we describe novel microscopic lesions associated with Glässer's disease such as endophthalmitis and thymic depletion. Thus, our findings indicate that SV7 strain 174 causes classical signs of Glässer's disease in colostrum-deprived piglets and some caution should be used in employing vaccine strategies based on association between capsular serovar and virulence.

No abstract

Background: Osteosarcoma is a malignant mesenchymal tumor with a wide variety of histological patterns. It is the primary bone neoplasia diagnosed in most domestic animal clinic, but rare in farm animals. The tumor develops both the appendicular skeleton as the axial skeleton, the latter being less affected. Generally it has a fast, painful and infiltrative grow, being observed metastasis. This study aims to report a case of metastatic osteoblastic osteosarcoma in the nasal bone of a bovine, diagnosed at the Animal Pathology Laboratory at the University of Passo Fundo (UPF), featuring its pathological and immunohistochemical aspects.Case: A 5 year old Wagyu female beef cattle, was treated at the Veterinary Hospital of the University of Passo Fundo. The animal had swelling in the left nasal plan, dyspnoea and anorexia. It was held cytology and biopsy which revealed malignant mesenchymal neoplasm compatible with osteosarcoma. The clinical picture has worsened and the animal died. At necropsy, the left nasal plane, had ulcerated tumor mass measuring 15x12.5x7.5 cm, hard and firm consistency with whitish color that seeped up to the turbinates and sinuses. In the lung, there were numerous nodules of tumor appearance, adhered to the parietal pleura, similar to bone tissue. In the histopathological analysis, proliferation of neoplastic cells located in the deep dermis was observed, cell thick, well-defined and infiltrative, arranged in bundles, loosely grouped with rounded shape, sometimes oval, with distinct boundaries. There were areas with formation of osteoid matrix calcification and tumor necrosis. It was observed lung and regional lymph nodes metastasis. Tissue samples were subjected to immunohistochemistry (IHC), was performed using the polymer method with horseradish peroxidase (HRP), with positive control, using a panel of antibodies. Neoplastic cells were immunoreactive for vimentin and negative for other antibodies. Thus, confirmed the case of mesenchymal origin and bone tumor.Discussion: Osteosarcoma developing in the axial skeleton, more precisely in the nasal bone, in animals of this age group, is not found frequently in the literature. However, when they occur, they have unilateral injury, remarkable facial deformities, dyspnea and infiltration of adjacent tissues. During necropsy there was observed a mass of hard consistency suggesting bone tissue in the nasal plane, there was also observed whitish spots on the lung and lymph nodes. Through microscopic analysis was obtained the classification of osteoblastic osteosarcoma. Being a malignant tumor it has a fast and infiltrative growth, there was visualized metastasis in lung and mediastinal lymph nodes. The samples submitted to immunohistochemistry were positive for vimentin and negative for other antibodies. No treatment with chemotherapy, radiation therapy or surgical intervention to remove the tumor was possible to be performed. Due to the severity of the clinical condition, the mass location, which couldn’t be obtained a safe surgical margin and it was financially unviable. The presumptive diagnosis of osteosarcoma was based on clinical history, anamnesis and cytological examination. However, the histopathological examination was essential to confirm the diagnosis. Through immunohistochemical examination, it was found the histogenesis, allowing to exclude other neoplasias. This technic was essential to characterize osteosarcoma due to the shortage reports of this neoplasia in farm animals, therefore, very important in veterinary medicine diagnosis.Keywords: neoplasia, bone, axial skeleton, ruminant, immunohistochemical and anatomopathological aspects.

Lawsonia intracellularis is the etiologic agent of porcine proliferative enteropathy (PPE), an inflammatory bowel disease with a major economic impact on the pig industry. The serological diagnosis of PPE can be performed using Blocking or Indirect ELISA, Immunoperoxidase Monolayer Assay (IPMA) and Indirect Fluorescence Antibody Test (IFAT). Here, we designed a most sophisticated immunological method for the detection of porcine anti-L. intracellularis IgGs, named Flow Cytometry Antibody Test - FCAT. This assay uses whole, live-attenuated L. intracellularis bacteria derived from a commercial vaccine. For the assay, we set up the optimal antigen concentration (106 bacterium/assay), primary antibody dilution (1:100), time of incubation (20 min), antigen stability (15 days), precision (coefficient of variation - CV < 10%), reproducibility (CV ≤ 13%) and Receiver Operating Characteristic (ROC). When using a cut-off of >15.15% for FCAT, we determined that it showed a sensitivity of 98.8% and specificity of 100%. The rate of agreement with IPMA was 84.09% with a kappa index of 0.66. FCAT was used to screen 1,000 sera from non-vaccinated pigs housed in 22 different farms and we found that 730 pigs (73%) from 16 farms (72.7%) had L. intracellularis IgG. This high prevalence confirms that L. intracellularis is endemic on Brazilian pig farms. Finally, we determined that FCAT is an easy to perform diagnostic assay and we would highly recommend it for: i) seroepidemiological studies; ii) evaluation of infection dynamics; and iii) characterization of the humoral response profile induced by vaccines.

O presente estudo objetivou relatar um caso de broncopneumonia abscedativa associada à hérnia diafragmática em ouriço-cacheiro (Sphiggurus villosus). Um ouriço-cacheiro (S. villosus) apresentava apatia e dispneia há meses e houve suspeita de pneumonia. O animal recebeu tratamento, porém foi a óbito e foi submetido a exame anatomopatológico. As alterações macroscópicas foram sugestivas de pneumonia envolvendo os brônquios principais, associada à hérnia diafragmática decorrente da presença de abscesso localizado no pulmão esquerdo. À histopatologia, observou-se severa broncopneumonia abscedativa multifocal crônica com compressão do parênquima pulmonar, atelectasia, enfisema e severa pleurite fibrinossupurativa crônica difusa.

Background: Gastric neoplasms are uncommon in dogs, especially those affecting smooth muscle layers. Leiomyoma is a smooth muscle benign neoplasm, which requires surgical resection. Pylorectomy and gastroduodenostomy (Billroth I procedure) is the most indicated technique in cases not affecting the biliary and pancreatic tracts. Thus, the purpose of this study was to report a successful case of Billroth I procedure in a bitch presenting antrum pyloric obstructive leiomyoma. Case: A 12-year-old, non-spayed, Cocker Spaniel bitch was admitted presenting depression, hyporexia, postprandial vomiting and sparse episodes of hematemesis, for 30 days. Clinical suspicion on obstructive gastric outflow disease was established. Bloodwork (complete blood count, BUN, albumin, ALP and ALT), abdominal ultrasound and thoracic radiographs were assessed. The patient undergone upper gastrointestinal endoscopy. On endoscopic evaluation, small hemorrhagic mucosa ulcers were visualized on the gastric body, antrum and pylorus. Moreover, a sessile, ulcerated, round-shape and infiltrated antral-pyloric mass was seen. The mass was 1.5-2.0 cm in diameter and apparently involved the smooth muscle layer, causing severe pyloric obstruction. However, endoscopic evaluation of the duodenum was possible. Several biopsy samples were taken from the neoplasm and sent for histopathologic assessment. The result was not conclusive due to low quality samples. The patient had progressive worsening of obstruction episodes and required surgery. A wide-margin pylorectomy and gastroduodenostomy (Billroth I procedure) was carried out. The retrieved specimen was sent to histopathological and immunohistochemistry (IHC) assessment. Positive staining for actin and desmin confirmed smooth muscle origin of the mass and histopathological assessment confirmed leiomyoma. The patient underwent regular periodic postoperative assessments, revealing progressive clinical improvement and normal weight gain. Control upper gastrointestinal endoscopy was performed. Gastric ulcers were completely healed and gastroduodenal anastomosis was functional. The anastomotic scar tissue was sampled and revealed chronic and normal healing process. Complete healing was confirmed and the patient was discharged. Discussion: Gastric neoplasms are not common in dogs. However, severe obstruction of gastric outflow is a potential risk for complications in those cases. Upper gastrointestinal endoscopic assessment is important not only for diagnosis, but also for surgery decision making. In the current study, gastroscopy provided accurate preoperative evaluation of severity of pyloric obstruction and diagnosis of secondary gastric ulcers. Direct visualization of lesions and multiple biopsy sampling were performed. The presence of neoplasms over 2-cm in diameter indicates need for complete laparoscopic or conventional surgical resection. In this case report, open resection was carried out due to prohibitive cost of laparoscopic approach, mass dimensions and probable involvement of deeper tissue layers. In conclusion, pylorectomy and gastroduodenostomy (Billroth I procedure) was curative and provided good prognosis following resection of an antrum pyloric obstructive leiomyoma. Endoscopy was critical for both diagnosis and decision-making towards surgery for gastric outflow obstruction due to an antrum pyloric neoplasm. Histopathological and immunohistochemistry assessment confirmed neoplasm type and assured oncological safety of resection with wide margins. Keywords: gastric neoplasms, smooth muscle tumor, endoscopy, dog.