Valíria Duarte Cerqueira

Meningoencefalite e polioencefalomalacia causadas por Herpesvírus bovino-5 no estado do Pará

Four outbreaks of meningoencephalitis in 1 to 2 years old cattle caused by Bovine herpesvirus-5 are reported in four municipalities in the state of Para, northern Brazil. In three outbreaks only one animal was affected, in another 3 cattle were affected. Main clinical signs were incoordination, dullness, blindness, recumbence, and opisthotonus. Death occurred after a clinical manifestation period of 3-4 days. Softening and yellowish areas were observed grossly in the cerebral cortex. The histology revealed poliencephalomalacia in the cerebral cortex, thalamus and basal nuclei, and non suppurative encephalitis and meningitis, and eosinophilic intranuclear inclusion bodies in astrocytes. The diagnosis was based on the typical microscopic lesions.

Intoxicação por Ipomoea carnea subsp. fistulosa (Convolvulaceae) em caprinos na Ilha do Marajó, Pará

Ipomoea carnea subsp. fistulosa is a swainsonine-containing plant causing a glycoprotein storage diseases in ruminants, mainly in goats in northeastern Brazil. Seven farms were visited on the Marajo Island, state of Para, northern Brazil, six in the municipality of Cachoeira do Arari and one in the municipality of Soure. In all farms native pastures had shortage of forage and were largely invaded by I. carnea subsp. fistulosa. On the three farms goats presented difficulties in standing, ataxia, hypermetria, wide-based stance, lateral gait, intention tremors, spastic paresis or weakness, abnormal postural reactions, nystagmus, loss of equilibrium and falling to the side or backward. On two farms the prevalence was of 32% (23/71) and 100% (32/32). On another farm one goat out of 19 had severe clinical signs, but the others of the flock were not examined clinically. Cattle, sheep and buffaloes were not affected. Six goats were euthanized and necropsied. No gross lesions were observed. Upon histological examination the main lesion was the vacuolization of the perikaryon of neurons and cytoplasm of epithelial cells of thyroid, liver, kidney, pancreas and macrophages of different organs. In the central nervous system the vacuolization of the perikaria was more severe in Purkinje cells of the cerebellum and in nuclei of the brain stem, mainly the cerebellar nuclei. Wallerian degeneration of axons and gliosis was also observed. The high frequency of the disease on the three farms suggests that poisoning by I. carnea subsp. fistulosa is very important for goats on Marajo Island where there are large amounts of the plant in the pastures.

Detection of Mycobacterium bovis in bovine and bubaline tissues using nested-PCR for TbD1.

In the present study, a nested-PCR system, targeting the TbD1 region, involving the performance of conventional PCR followed by real-time PCR, was developed to detect Mycobacterium bovis in bovine/bubaline tissue homogenates. The sensitivity and specificity of the reactions were assessed with DNA samples extracted from tuberculous and non-tuberculous mycobacteria, as well as other actinomycetales species and DNA samples extracted directly from bovine and bubaline tissue homogenates. In terms of analytical sensitivity, the DNA of M. bovis AN5 was detected up to 1.56 ng with conventional PCR, 97.6 pg with real-time PCR, and 1.53 pg with nested-PCR in the reaction mixture. The nested-PCR exhibited 100% analytical specificity for M. bovis when tested with the DNA of reference strains of environmental mycobacteria and closely-related Actinomycetales. A clinical sensitivity value of 76.0% was detected with tissue samples from animals that exhibited positive results in the comparative intradermal tuberculin test (CITT), as well as from those with lesions compatible with tuberculosis (LCT) that rendered positive cultures. A clinical specificity value of 100% was detected with tissue samples from animals with CITT- results, with no visible lesions (NVL) and negative cultures. No significant differences were found between the nested-PCR and culture in terms of detecting CITT+ animals with LCT or with NVL. No significant differences were recorded in the detection of CITT- animals with NVL. However, nested-PCR detected a significantly higher number of positive animals than the culture in the group of animals exhibiting LCT with no previous records of CITT. The use of the nested-PCR assay to detect M. bovis in tissue homogenates provided a rapid diagnosis of bovine and bubaline tuberculosis.

Direct detection of Mycobacterium tuberculosis complex in bovine and bubaline tissues through nested-PCR

Post-mortem bacterial culture and specific biochemical tests are currently performed to characterize the etiologic agent of bovine tuberculosis. Cultures take up to 90 days to develop. A diagnosis by molecular tests such as PCR can provide fast and reliable results while significantly decreasing the time of confirmation. In the present study, a nested-PCR system, targeting rv2807, with conventional PCR followed by real-time PCR, was developed to detect Mycobacterium tuberculosis complex (MTC) organisms directly from bovine and bubaline tissue homogenates. The sensitivity and specificity of the reactions were assessed with DNA samples extracted from tuberculous and non-tuberculous mycobacteria, as well as other Actinomycetales species and DNA samples extracted directly from bovine and bubaline tissue homogenates. Regarding the analytical sensitivity, DNA of the M. bovis AN5 strain was detected up to 1.5 pg by nested-PCR, whereas DNA of M. tuberculosis H37Rv strain was detected up to 6.1 pg. The nested-PCR system showed 100% analytical specificity for MTC when tested with DNA of reference strains of non-tuberculous mycobacteria and closely-related Actinomycetales. A clinical sensitivity level of 76.7% was detected with tissues samples positive for MTC by means of the culture and conventional PCR. A clinical specificity of 100% was detected with DNA from tissue samples of cattle with negative results in the comparative intradermal tuberculin test. These cattle exhibited no visible lesions and were negative in the culture for MTC. The use of the nested-PCR assay to detect M. tuberculosis complex in tissue homogenates provided a rapid diagnosis of bovine and bubaline tuberculosis.

Intoxicação por Ipomoea asarifolia em ovinos e bovinos na Ilha de Marajó

To determine plant poisonings occurring on Marajo Island, state of Para, northern Brazil, 7 farms were visited. All farms had native pastures with low forage availability severely infected by Ipomoea asarifolia. In 5 farms poisoning in sheep by the plant was reported. The disease occurs mainly during the dry period and lambs are more frequently affected than adult sheep. Sheep with clinical signs were observed in 2 farms. In 4 establishments farmers reported the occurrence of I. asarifolia poisoning in cattle. In one farm affected cattle were observed during two visits, one during the dry season and another at the start of the raining season. Deaths are observed mainly in calves. In both species the poisoning occurs every year with variable morbidity and low mortality. One bovine and one sheep with severe clinical signs were euthanized and post-mortem examination was performed. No gross or histologic significant lesions were observed. In all farms buffaloes were raised together with cattle and sheep, and in 3 farms goats were also raised. None of the farmers reported the intoxication in these species.

Colic Caused by Panicum Maximum Toxicosis in Equidae in Northern Brazil

In the Amazon region of northern Brazil, Panicum maximum cultivars Mombaça, Tanzânia, and Massai cause severe colic and death in horses and mules. The disease occurs in the rainy season, when sprouting pastures are grazed by equidae. In the 8 separate disease outbreaks studied, a total of 52 out of 153 equidae were affected, including 19 that died (10 mules and 9 horses). Clinical signs were colic and abdominal dilatation, with a clinical manifestation period of 12 hr to 4 days. Serum activities of gamma-glutamyl transferase and aspartate aminotransferase were within reference intervals; however, serum urea nitrogen and creatinine concentrations were occasionally elevated. The primary gross and histologic lesions were observed in the digestive system. The stomach, small intestine, and large intestine had severe hemorrhages and occasional mucosal erosions and ulcerations. Ulceration and hemorrhage of the urinary bladder were rarely observed. Histologic examination revealed diffuse lymphoplasmacytic gastritis and enteritis with severe congestion, hemorrhage, and occasional epithelial necrosis and ulceration. Lymphocellular necrosis was occasionally observed within gut-associated lymphoid tissue. Tubular nephrosis occurred in some animals. Degeneration and occasional necrosis of bile duct epithelial cells and degeneration of hepatocytes were observed in the liver. Toxic pastures were negative for diosgenin- and yamogenin-based saponins, and oxalate concentrations were within reference intervals for the species. The toxin or toxins causing disease and the reason for the toxicity of the plant in the northern region are unknown.

Sinais clínicos, lesões e alterações produtivas e reprodutivas em caprinos intoxicados por Ipomoea carnea subsp. fistulosa (Convolvulaceae) que deixaram de ingerir a planta

The aim of this research was to study the clinical signs, productive and reproductive performance, and lesions of goats poisoned by Ipomoea carnea subsp. fistulosa after removal from the paddocks where the plant occurred. Thirty seven goats were divided into four groups: Group 1 consisted of 14 goats with poor body conditions and mild to severe nervous signs, acquired from a farm where the plant occurred; Group 2 (control) consisted of 10 goats which had also poor body conditions, but were acquired from a farm where the plant did not occur; Group 3 consisted of two goats with clinical signs of intoxication and which were slaughtered on the farm where they became poisoned; Group 4 consisted of 11 goats slaughtered as controls for the study of gross and histological lesions. The animals from Group 1 and 2 were evaluated for a period of 12 months on a farm located in the municipality of Castanhal/Para, in a paddock where the plant did not occur. Six months later, the animals of Group 1 continued with poor body condition, rough hair coat, and nervous signs, especially intention tremors, what became with time less noticeable. In the same period, the goats of Group 2 gained an average of 13 kg body weight. Goats from Group 1 showed to be more susceptible to gastrointestinal parasites than those from Group 2. From the eight goats of Group 1 remaining on the farm only 4 became pregnant and delivered three kids which died shortly after birth, while all goats from Group 2 got pregnant and delivered healthy kids. At necropsy, two goats from Group 1 showed cerebellar atrophy. The main histological change observed in animals of Groups 1 and 3 was a decreased number of Purkinje cells in the cerebellum. It is concluded that goats chronically intoxicated by I. carnea and which discontinued to ingest the plant but showed still clinical signs, even though diminished in intensity, had poor productive and reproductive performance and were highly susceptible to gastrointestinal parasites. For economical reasons, it is suggested that farmers cull affected animals which show still nervous signs 15 days after the end of I. carnea consumption. The most common permanent clinical signs are intention tremors, probably due to the loss of Purkinje cells, what could be primarily responsible for the malnutrition of the goats, the resulting reproductive failure and increased susceptibility to gastrointestinal parasites.

Aspectos toxicológico, clínico-patológico e ultraestrutural das intoxicações iatrogênica e experimental por vitamina D em coelhos

Toxicological, clinic-pathological and ultrastructural aspects of iatrogenic and experimental subcutaneous poisoning in rabbits by vitamin D are described. Clinically the animals showed signs of cardiovascular insufficiency, as ascite and lung edema, hyporexia, anorexia, mucous diarrhoea, loss of weight and apathy. The classical alterations of minera-lization and, occasionally, ossification of the cardiovascular system, as well the lesions of kidneys, lungs, stomach, among other organs, were reproduced by the subcutaneous administration of an oily solution of cholecalciferol (non-activated vitamin D3).

Queilite angular traumática em eqüinos associada à ingestão de Panicum maximum

Uma condicao com aumento da fenda bucal de equinos por lesao na comissura labial foi estudada. Este aumento tinha extensao variavel e era uni ou bilateral. Na mucosa da bochecha da comissura labial exposta havia pequenas erosoes. Durante a mastigacao havia perda de pequena quantidade de capim e saliva pela fenda bucal aumentada. Os animais apresentavam bom estado nutricional. O exame histopatologico de tecido retirado da comissura labial revelou epidermite superficial. Nas quatro propriedades onde se verificou o problema, constatou-se que os equinos eram mantidos em sistema extensivo de criacao em pastagem de Panicum maximum (variedades Tanzânia, Mombaca, Tobiata e Coloniao), com folhas maduras, altas, lignificadas e de bordos cortantes. De acordo com os dados epidemiologicos, com os achados clinicos e histopatologicos, conclui-se que essas lesoes foram causadas pela acao cortante das folhas de Panicum maximum, associada a forma de apreensao da pastagem alta e mastigacao pelos equinos.

Surto de tétano em búfalos (Buballus bubalis) no Estado do Pará

Descreve-se um surto de tetano em bufalos da raca Murrah em uma propriedade situada no municipio de Sao Caetano de Odivelas, localizado na regiao metropolitana de Belem, estado do Para. Do rebanho de 250 bubalinos, 80 animais foram vacinados contra raiva por via intramuscular na regiao da garupa. Em um periodo de 15 a 19 dias apos a vacinacao quatro animais adoeceram, um morreu com dois dias de evolucao, um foi eutanasiado in extremis no setimo dia apos o inicio dos sinais clinicos e os demais se recuperaram apos tratamento. Nos bubalinos, o primeiro sinal clinico observado foi o prolapso da terceira palpebra, em especial quando o animal era estimulado, seguido por andar rigido, manifestado por dificuldade de flexao dos membros e permanencia em decubito lateral com os membros estendidos, palpebras muito abertas, sialorreia, hiperexcitabilidade, orelhas eretas, leve trismo e acumulo de alimento na cavidade oral. A necropsia foi evidenciada uma area de coloracao amarelada com presenca de exsudacao purulenta na musculatura da regiao da garupa, local de aplicacao da vacina. Ao exame histopatologico nao foram evidenciadas alteracoes significativas. Em dois animais foi realizado tratamento com penicilina por via intramuscular e soro antitetânico por via intramuscular e sub-aracnoide; apos duas semanas esses animais se recuperaram. Diante do quadro clinico, dos dados epidemiologicos e da ausencia de lesoes histologicas foi feito o diagnostico de tetano. Concluiu-se que o tetano e uma doenca a ser considerada na bubalinocultura no Brasil. A infeccao, provavelmente ocorreu durante o procedimento de vacinacao, atraves injecoes intramusculares utilizando agulhas contaminadas.