Milene Schmitz

Use of lectin histochemistry to diagnose Sida carpinifolia (Malvaceae) poisoning in sheep

by standard histological methods and stained with haematoxylin and eosin. Microscopically, there was distension and vacuolation of Purkinje cells in the cerebellum (Fig 1) and of neurons in the cerebral cortex, thalamus, mesencephalon and spinal cord. Cytoplasmic vacuolation was also present in the epithelium of the pancreatic acinus and renal tubules, follicular epithelium of the thyroid, in hepatocytes, and in macrophages of the lymphoid tissues. Axonal spheroids were observed in the brain and spinal cord, particularly in the granular layer of the cerebellum. Lectin histochemistry was conducted on formalin-fixed, paraffin-embedded sections of the cerebellum and pancreas. The lectins used were obtained commercially (E-Y Labs) and are listed in Table 1. After deparaffinisation, the sections were incubated in 0·3 per cent hydrogen peroxide (H2O2) in methanol for 30 minutes at room temperature, rinsed several times in 0·01M phosphate-buffered saline (PBS), pH 7·2, and treated with 0·1 per cent bovine serum albumin in PBS for 15 minutes. Subsequently, they were incubated with biotinylated lectins for one hour, followed by incubation with avidinbiotin-peroxidase complex (Vector Labs) for 45 minutes. The peroxidase was marked by incubation for four to 10 minutes with buffered Tris-HCl, 0·05M, pH 7·6 solution containing 0·02 per cent diaminobenzidine and 0·05 per cent H2O2.All the sections were counterstained with Mayer’s haematoxylin. Each lectin was used at a dilution of 30 μg/ml in PBS, except for Arachis hypogaea (Table 1), which was applied at 10 μg/ml. As controls for the lectin histochemical procedure, the lectins were omitted or blocked by incubating them with their blocking sugars (0·1 to 0·2 per cent in PBS) for one hour at room temperature before application to the sections (Leathem 1986). The results of the lectin-binding patterns of affected and control sheep are summarised in Table 2. The cytoplasm of

Aspectos clínico-patológicos associados à circovirose suína no Rio Grande do Sul

No periodo de janeiro a julho de 2004, foram realizadas 97 necropsias de suinos que apresentaram subdesenvolvimento, aumento generalizado de linfonodos, palidez ou ictericia de mucosas e, ocasionalmente, problemas respiratorios. As principais lesoes macroscopicas encontradas incluiram aumento generalizado de linfonodos, pulmoes nao colapsados com bordos arredondados e areas de consolidacao, especialmente crânio-ventrais, alem de edema de septos interlobulares. Os rins estavam palidos, aumentados de volume e com pontos brancos que, difusamente distribuidos na superficie, infiltravam em forma de estrias ate a zona cortical. Alguns apresentavam pequenos pontos vermelhos, semelhantes a petequias, difusamente distribuidos no cortex renal. O achado histologico comum foi a presenca, em graus variaveis, de infiltrados linfo-histiocitarios em linfonodos, pulmoes e rins. O teste imuno-histoquimico utilizando anticorpo policlonal anti-circovirus suino tipo 2 foi positivo em amostras provenientes de 50 (89,2%) entre 56 suinos examinados.

Sida carpinifolia (Malvaceae) poisoning in fallow deer (Dama dama).

Abstract A captive fallow deer (Dama dama) in a zoo was spontaneously poisoned after consumption of Sida carpinifolia. The paddock where cervids were kept was severely infested by S. carpinifolia. The deer developed a neurological syndrome characterized by muscular weakness, intention tremors, visual and standing-up deficits, falls, and abnormal behavior and posture. Because a severe mandibular fracture and the consequent deteriorating condition, it was euthanized. Main microscopic findings were swelling and multifocal cytoplasmic vacuolation in the Purkinje cells. The cytoplasm of multiple cells of the cerebellum, especially the Purkinje cells, stained with the lectins Concanavalia ensiformis, Triticum vulgaris, and succinylated Triticum vulgaris. Diagnostic possibilities such as bovine diarrhea virus, rabies, and transmissible spongiform encephalopathy were excluded. The report focuses on the risk of maintaining S. carpinifolia populations in zoo enclosures of wild herbivores.

Enterotoxemia em caprinos no Rio Grande do Sul

Five outbreaks of caprine enterotoxaemia in Rio Grande do Sul, Brazil, were studied. The animals were found dead or had a clinical course that usually lasted 2-3 hours. From two farms a clinical manifestation period of 12 hours was reported. Clinical signs were characterized by depression, marked abdominal discomfort, profuse watery diarrhea with fibrin clots, and death. Thirteen necropsies were performed and hydropericardium, hydrothorax and hydroperitoneum were commonly found. The mucosa and serosa of the colon were congested, and its contents was watery with multiple fibrin clots. Serosal hemorrhages and fibrin clots in the gallbladder were also seen. Fibrinous colitis and thyphilitis were the most frequent histological changes. Cerebral microangiopathy was observed in one case, which was characterized by acute perivascular proteinaceous edema around arterioles of the nucleus caudatus and thalamus. Large numbers of Gram-positive rods, often in clumps and with morphology consistent with Clostridium perfringens, were seen in intestinal smears. The intestinal contents of six goats were positive for epsilon toxin by mouse neutralization test. These findings suggest that enterotoxaemia is an important disease of goat flocks in southern Brazil.

Intoxicação por Erythroxylum deciduum (Erythroxylaceae) em ovinos

The epidemiological, clinical and pathological aspects of natural poisoning caused by Erythroxylum deciduum fruits in sheep are reported. The outbreak occurred from January to March of 2004, in Lagoa Vermelha county, state of Rio Grande do Sul, Brazil. The poisoning was experimentally reproduced by oral administration of E. deciduum fruits to 5 sheep.Three of them developed neurological signs and died. Poisoning was caused with a single dose of 60g/kg or when the dosage was fractioned into at least 4 doses of 17 g/kg given every 12 hours. The main clinical signs in natural and experimentally poisoned sheep were ataxia, hyperexcitability and muscular tremors which where more pronounced when the animals were moved. At the final stage, dyspnea with abdominal breathing and cyanosis was observed. The most significant alterations found at necropsy were pronounced edema, lung congestion and presence of the fruits or seeds of E. deciduum in the ruminal content of all animals. Histologically, except edema and pulmonary congestion, there were no other significant changes observed.