| Summary: | Made available in DSpace on 2016-04-28T20:16:24Z (GMT). No. of bitstreams: 1
2007- Flavio Augusto Soares Graca01.pdf: 782491 bytes, checksum: aca3b139eb03d06af06c5dd1c95ec3d7 (MD5)
Previous issue date: 2007-04-26 === Crotalus poisoning was experimentally reproduced by inoculation of Crotalus durissus
terrificus (South American Rattlesnake) venom by subcutaneous via in ten clinically healthy
mixed breed bovine, weighing between 125 and 449 kg and aged 12 to 36 months. Two
bovine of the same age range and breed standard were used as controls. The bovine that
received a 0.03 mg/kg p.v. dose died 7h40min after inoculation. A 0.015 mg/kg p.v. dose
provoked death in four out of seven inoculated bovine, while two bovine experimentally
poisoned with 0.0075 mg/kg p.v. became mildly sick and recovered. Onset of symptoms
occurred between 1h30min and 13h45min after inoculation. Evolution oscillated between
5h25min and 44h59min for bovine deaths and between 33h15min and 17 days for bovine that
recovered. The principal nervous signs observed were diminished response to external stimuli,
hypotonic reflexes, dragging of hooves along the ground, apparent lethargy, difficulties in
moving around obstacles, ocular globe paralysis, lateral and sternal decubitus and tongue
paralysis. Constant adypsia and petechiae in the conjunctival and vaginal mucosa was also
verified. A discrete to moderate increase in bleeding time was verified in six bovine and a
moderate increase in partial thromboplastin time was activated in seven bovine. Moderate
leukocytosis with neutrophilia, relative lymphopenia, eosinopenia and monocytosis occurred
and a discrete increase in the number of rods. A significant increase in creatine kinase serum
levels was observed, of a ten-fold order. No significant alterations were observed at
urinalysis. At necropsy there were minimal edema at the inoculation site, discrete petechiae
and suffusions in the epicardium, omentum, biliary vesicle and bladder mucosa.
Histopathological examination revealed necrosis (hyalinization) of groups or isolated
myocytes in ten different muscles examined, both close and distant from the inoculation site.
Faced with the clinic-pathological picture, observations were made regarding the diagnosis of
crotalus envenomation and its differentiation from deseases which course with paralysis and
muscular necrosis in cattle in Brazil. === Reproduziu-se experimentalmente o envenenamento crot?lico, atrav?s da inocula??o, por via
subcut?nea, do veneno de Crotalus durissus terrificus (Cascavel sul-americana) em dez
bovinos mesti?os, com peso variando entre os 125 e 449 quilogramas e idade entre 12 e 36
meses. Dois animais na mesma faixa et?ria e padr?o racial foram utilizados como controle. O
animal que recebeu dose de 0,03 mg/kg p.v. foi a ?bito 7h40min ap?s a inocula??o. A dose de
0,015 mg/kg p.v. induziu o ?bito em quatro de sete bovinos inoculados, enquanto os dois
animais que receberam 0,0075 mg/Kg, adoeceram discretamente e se recuperaram. Os
sintomas tiveram in?cio entre 1h30min e 13h45min ap?s a inocula??o. A evolu??o oscilou
entre 5h25min e 44h59min para os animais que morreram e entre 33h15min e 17 dias entre os
animais que se recuperaram. Os principais sinais nervosos observados foram diminui??o da
resposta aos est?mulos externos, reflexos hipot?nicos, arrastar dos cascos no solo, aparente
letargia, paralisia do globo ocular e da l?ngua, dec?bito esternal e lateral. Verificou-se tamb?m
adipsia constante e pet?quias nas mucosas vaginal e conjuntival. Observaram-se discreto a
moderado aumento do tempo de sangramento em seis animais e moderado aumento do tempo
de tromboplastina parcial ativada em sete bovinos. Houve moderada leucocitose com
neutrofilia, linfopenia relativa, eosinopenia, monocitose e discreto aumento do n?mero de
bast?es. Foi evidenciado significativo aumento dos n?veis s?ricos de creatinaquinase, da
ordem de dez vezes. N?o foram observadas altera??es significativas atrav?s da urin?lise. ?
necropsia constataram-se edema quase impercept?vel no local da inocula??o, discretas
pet?quias e sufus?es no epic?rdio, omento, ves?cula biliar e mucosa da bexiga. Os exames
histopatol?gicos revelaram necrose (hialiniza??o) de grupos de mi?citos ou em mi?citos
isolados em dez diferentes m?sculos esquel?ticos examinados, pr?ximos ou distantes do local
de inocula??o. Diante do quadro cl?nico-patol?gico foram feitas observa??es sobre o
diagn?stico do envenenamento crot?lico e sua diferencia??o com enfermidades que cursam
com paralisia e necrose muscular em bovinos do Brasil.
|
|---|
