Silvia de Araújo França

Infection of sparrows (Passer domesticus) and different mice strains with Lawsonia intracellularis

The susceptibility of sparrows (Passer domesticus) and strains of mice (Swiss, BALB/c, C-57 and DB-A) to Lawsonia intracellularis infection was studied. Thirty-two sparrows were inoculated with pure culture of L. intracellularis and eleven received sham inoculum. Feces were collected on -1, 7, 14 and 21 days post infection (dpi) for detection of L. intracellularis by PCR. After 21 days, all sparrows were euthanized and the tissues processed for histology and immunohistochemistry (IHC). One hundred sixty mice of four different strains (n=40, per strain) were used. For each mouse strain, 16 animals received mucosa homogenate from a pig infected with L. intracellularis, 16 received pure culture of L. intracellularis and eight animals received sham inoculum. Two control and four inoculated mice from each group were euthanized on 7, 14, 21 and 28 dpi. Sections of intestine were collected for histologic analysis and IHC and pooled feces were collected for L. intracellularis PCR. None of the sparrows had any histologic lesions characteristic of proliferative enteropathy or antigen labeling by IHC. All sparrow fecal samples were negative by PCR. All mice strains studied had histopathological lesions typical of PE and IHC labeling consistent with L. intracellularis infection, especially those animals inoculated with pure culture. The most severe lesions were observed in DB-A and Swiss mice. Fecal shedding was detected in all mice strains, with peak at 14 dpi. We conclude that sparrows do not seem to be relevant in the epidemiology of L. intracellularis. The results showed variations in the lesions among the four mice strains used.

Equine coital exanthema in a stallion

Em agosto de 2008, um garanhao da raca Mangalarga Marchador, de quatro anos de idade, com historico clinico de apatia, inapetencia e edema de prepucio e escroto, apresentou, ao exame clinico, exsudato purulento fluindo pelo ostio prepucial, prepucio e mucosa peniana com inumeras lesoes circulares de bordos elevados e hiperemicos, centro ulcerado recoberto por material amarelado de aspecto fibrinoso, com distribuicao multifocal. Histologicamente, a mucosa peniana apresentou areas de ulceracao associadas a infiltrado inflamatorio misto, com necrose multifocal e moderado acumulo de fibrina, que se estendiam para o tecido conjuntivo adjacente. O diagnostico morfologico foi de balanopostite ulcerativa fibrino-necrotica multifocal intensa, similar ao encontrado em casos de exantema coital equino (ECE), causado pelo herpesvirus equino 3 (EHV-3). Amostra de pele do prepucio e sangue, colhido em EDTA, foram submetidos a ensaios de PCR especificos para EHV-3, observando-se a amplificacao de um produto de tamanho esperado de 518pb. A deteccao do EHV-3 foi confirmada por meio de seu sequenciamento, sendo a sequencia de nucleotideos depositada no GenBank sob o numero GQ336877. As sequencias de nucleotideos e as de aminoacidos deduzidos apresentaram identidade de 99% e 100%, respectivamente, com a sequencia de EHV-3 disponivel no GenBank, numero AF081188. Apos 15 dias de tratamento, houve completa cicatrizacao das lesoes, com despigmentacao da pele, principalmente, no prepucio e na bolsa escrotal. Com base nos achados clinicos, histopatologicos, PCR e sequenciamento, concluiu-se tratar de um caso de exantema coital equino, sendo o primeiro com confirmacao definitiva do agente etiologico no Brasil.

Indirect ELISA for diagnosis of Brucella ovis infection in rams

Brucella ovis is a major cause of epididymitis in sexually mature rams, resulting in subfertility, infertility, and economic losses for the sheep industry worldwide. The aim of this study was to develop an indirect ELISA (iELISA) using recombinant proteins, namely rBoP59 and rBP26, as antigens for serological diagnosis of B. ovis infection. The BoP59 and BP26 recombinant proteins were expressed in E. coli and purified by affinity chromatography. Antigenicity was tested by Western blot and iELISA. Standardization of iELISA was performed with 500ng and 1µg BoP59 and rBP26 per well, testing serum from uninfected and experimentally infected rams. rBP26 was effective in distinguishing positive from negative rams. The rBP26 iELISA developed in this study is the first to use a completely purified rBP26 as antigen resulting in high sensitivity (100%) and specificity (90.2%), and an overall accuracy equal to 1.0.

Antimicrobianos para o controle da enteropatia proliferativa suína

Porcine proliferative enteropathy (PPE), caused by the bacterium Lawsonia intracellularis, causes serious economic losses worldwide due to diarrhea and poor growth rate medication in young growing pigs (chronic disease form) and sudden death in finisher and replacement pigs (acute hemorrhagic form). Typical control programs have focused on antibiotics. Essentially, the effectiveness of an antimicrobial can be tested in vitro or in vivo. In vivo test can be developed with natural or experimentally infected pigs. In tests that the animals are experimentally challenged, the inoculation is done with pure culture of L. intracellularis or intestinal mucosal homogenate of pig with PPE. Antimicrobial use have been shown to be effective in reducing the clinical signs of PPE and to result in better performance in treated pigs than in untreated animals. In addition, it decreases fecal shedding and the severity of gross lesions. The most efficient antimicrobial groups of drugs discussed in this manuscript are macrolides, tetracyclines, lincosamides and pleuromutilins. All of them act by blocking bacterial protein synthesis.

Splendore-Hoeppli phenomenon in a cat with osteomyelitis caused by Streptococcus species

A 9-month-old male neutered mixed-breed cat had a history of chronic lameness of the right hind limb, which was non-responsive to antibiotic treatment. Hematologic analysis revealed marked neutrophilia and mild monocytosis. Radiography revealed extensive loss of cortical bone, and replacement with irregular and disorganized bone. There was loss of the normal cortico-medullary distinction, and the medullary cavity had an irregular radiodensity suggestive of osteomyelitis. Surgical curettage and antibiotics did not improve the clinical condition, and amputation was performed. Grossly, the skin over the right tibia was ulcerated with a viscous and granular exudate. At histopathology, there was marked diffuse pyogranulomatous dermatitis, myositis, periostitis and osteomyelitis associated with Splendore-Hoeppli phenomenon. In addition, there was marrow osteoproliferation and multifocal cortical loss, reabsorption, fibroplasia and endosteal bone formation. Gram staining revealed myriad slightly elongated Gram-positive bacteria, arranged in pairs or single chains, confirmed by polymerase chain reaction as Streptococcus species.

Multiple congenital defects in a newborn foal

A case of multiple congenital defects in a newborn foal is reported. The animal showed hypoplasia of the left pelvic limb bones, uterus unicornis, congenital diaphragmatic hernia, and unilateral renal and ureteral agenesis. This report includes the macroscopic and microscopic lesions observed in the case.

In-feed macrolide Leucomycin (Leucomag 30% PR) for prevention of proliferative enteropathy in experimentally infected pigs

The aim of this study was to evaluate the efficacy of orally administered leucomycin at 90 and 180ppm for the prevention of porcine proliferative enteropathy (PPE) in experimentally infected pigs. A total of 90 commercial five-week-old pigs were randomly assigned to receive leucomycin in feeding at 90 (T2), 180ppm (T3), or untreated (T1). All animals in the treated groups received medicated feed for 14 days starting one day before inoculation. Each pig was inoculated intragastrically with approximately 4.5x109 Lawsonia intracellularis in the form of porcine intestinal mucosal homogenate. Body weight, feed consumption and clinic signs were evaluated throughout the study. Necropsies and gross evaluation of intestines were performed in all animals on day 23 post-inoculation (pi) or at death, and ileum samples were collected for immunohistochemistry (IHC) for L. intracellularis. Clinical presentation of the disease was more evident in the non-medicated group (T1) than in the medicated ones (T2, T3) between days 16 and 21pi. Average daily gain, average daily feed consumption and feed conversion efficiency were better in groups treated with either dose of leucomycin. The total intestine lesion length per group (T1, T2 and T3) was 869, 473 and 331cm, respectively. The majority of the animals (84.4%) were positive for L. intracellularis antigen in ileum sections stained by IHC. Under the conditions of this study, leucomycin administered in feed at 90 and 180ppm for 14 days was effective in improving performance of pigs inoculated with intestinal homogenate containing L. intracellularis.

Mielolipoma adrenal bilateral em um cão

A case of bilateral adrenal myelolipoma in a 13-year-old female Poodle is reported. Acute septic peritonitis due to intestinal ulceration and perforation caused by a linear foreign body was the cause of death. The adrenal neoplasm was an incidental necropsy finding. The adrenal glands were grossly rounded, enlarged and friable, and had red-brownish parenchyma interwoven by slightly prominent white-yellowish foci. Histologically, the findings of differentiated adipocytes in large areas of the parenchyma, in association to hematopoietic cells and macrophages with hemosiderin were consistent with the diagnosis of adrenal myelolipoma.