Epidemiology, clinical signs, laboratorial and pathological findings in eight outbreaks of botulism in cattle in Rio Grande Do Norte state, Northeastern Brazil [Epidemiologia, sinais clínicos, achados laboratoriais e patológicos em oito surtos de botulismo em bovinos no Rio Grande do Norte]
Camara A.C.L.,Rural University |
De Miranda Oliveira C.M.,Rural University |
Do Vale A.M.,Rural University |
Batista J.S.,Laboratorio Of Patologia Veterinaria |
Soto-Blanco B.,Federal University of Minas Gerais
Acta Scientiae Veterinariae | Year: 2014
Background: Botulism is caused by a neurotoxin produced by Clostridium botulinum, a gram-positive bacterium, sporeforming anaerobe. In Brazil, this disease has relevant importance causing economic disturbance in livestock production. The present study aimed to report the epidemiology, clinical-pathological and laboratorial findings of eight outbreaks of botulism in cattle from Rio Grande do Norte, Northeastern Brazil. Material, Methods & Results: Clinical and epidemiological data of eight outbreaks of botulism were obtained during visits to farms from Mossoró, Serra do Mel, Governador Dix-Sept Rosado and Olho D'água dos Borges municipalities, located at the semiarid region of Rio Grande do Norte state, Northeastern Brazil. The outbreaks occurred in July 2009, August and September 2010, and April, May and October 2013. Blood and cerebrospinal fluid samples were collected from eleven and six animals, respectively, for laboratorial analysis. Ten cattle that recently died were necropsied, and fragments of several tissues (central nervous system, liver, kidney, heart and small intestine) were collected for histopathological examination. The observed clinical signs varied according to the clinical evolution of the disease, and included progressive paralysis of hindlimbs and sternal decubitus. The common clinical findings in all cattle was decreased muscular tonus of tongue and tail, difficulty swallowing and perianal hypoalgesia. However, one outbreak was characterized by the onset of symptoms in forelimb motor incoordination. All animals showed varying degrees of dehydration. The clinical course varied from hyperacute (within 24 h) to subacute (within 7 days). All affected cattle died, totalizing 70 deaths. The morbidity and mortality of the disease was 12.3%, and the lethality reached 100%. Hematology revealed the occurrence of leukocytosis with neutrophilia and hemoconcentration in three and two animals, respectively. Six animals showed hyperproteinemia. The cerebrospinal fluid analysis showed density in the upper limit (1.010) or increased density (1.015 and 1.020) in five of six cases (83.3%), while the leucocytes remained within the physiological limits, reaching the maximum of four leukocytes/μL. Gross pathological findings consisted of pulmonary hypostasis and petechial and ecchymotic hemorrhages in the pericardium, and associated to the long period of recumbency or death agony, respectively. The analyzed tissue fragments showed no significant microscopic change. Discussion: The outbreaks of botulism in cattle from Rio Grande do Norte state were linked to the lack or inadequate mineral supplementation and the absence or improper immunization against botulinic toxin. The nutritional deficiency of phosphorus is well known in the farms of the region and the carcasses of dead animals are usually not removed from the grasslands, which are factors that favor the osteophagia by cattle. Another relevant aspect is still the existence of farmers releasing their cattle into areas of dumps or allowing the access to inappropriate foods. Although forbidden by law, the use of poultry litter for animal feeding was the probable cause of the one outbreak, since no other risk factor was identified at the property. Thus, the findings of this study show the need for the establishment of an efficient control and prophylaxis program against the botulism.
Pierezan F.,Federal University of Santa Maria |
Oliveira Filho J.C.,Federal University of Santa Maria |
Carmo P.M.,Federal University of Santa Maria |
Lucena R.B.,Federal University of Santa Maria |
And 3 more authors.
Pesquisa Veterinaria Brasileira | Year: 2010
An outbreak of chronic aflatoxicosis is reported in dairy calves. Forty 4-month-old male Holstein calves of approximately 100kg were kept in individual cages of 1.5 x 1.5m and were fed a ration constituted by alfalfa hay, broken corn and milk substitute. Six calves (15%) died after presenting a disease characterized by general unthriftiness, diarrhea, rough hair coats, abdominal pain, prolapsed rectum, grinding of teeth, and lying down and rolling. The clinical course, as observed by the owners, was 2-3 days; however many calves in this lot that did not die, remained underdeveloped. Three calves were necropsied. Necropsy findings included firm, light tan livers and marked hydrothorax, ascites and edema of the mesentery, mesocolon and of the mucosal folds of the abomasum. Main histopathological changes were restricted to the liver and consisted of fibrosis, moderate megalocytosis, biliary duct hyperplasia and venoocclusive disease. The search for Senecio spp. contamination in the alfalfa hay resulted negative. The analysis by thin layer chromatography of the corn fed to calves revealed 5,136 ppb of aflatoxin B1. A diagnosis of aflatoxicosis was made based on the characteristic clinical signs and pathology, on the absence of Senecio spp. in the food and on the presence of high levels of aflatoxin in the corn fed to the calves.
MacEdo J.S.,Federal Rural University of Pernambuco |
Rocha B.P.,Federal Rural University of Pernambuco |
Colodel E.M.,Laboratorio Of Patologia Veterinaria |
Freitas S.H.,Hospital Veterinario |
And 4 more authors.
Toxicon | Year: 2015
The aim of this study was to evaluate the toxicity of Stryphnodendron fissuratum pods in Guinea pigs (Cavia porcellus) and test the hypothesis that this plant has teratogenic effects. Thus, sixteen Guinea pigs were randomly divided into four groups of four animals each. Groups 10, 20 and 40 consisted of Guinea pigs that received commercial food that contained crushed pods of S. fissuratum at concentrations of 10, 20 and 40 g/kg, respectively, during the period of organogenesis. Control group consisted of Guinea pigs under the same management conditions that did not receive crushed pods of S. fissuratum in their food. In all experimental groups, the main clinical signs of poisoning consisted of anorexia, prostration, absence of vocalizations, alopecia, diarrhea, and abortions within the adult Guinea pigs. Those that did not abort gave birth to weak, malnourished pups, some of which had fetal malformations. The main teratogenic changes consisted of eventration, arthrogryposis, amelia of the forelimbs, anophthalmia, microphthalmia, anotia and agnathia. The reductions in the number of offspring and the malformations observed in the experimental groups suggest that S. fissuratum affects fetal development and is teratogenic. © 2015 Elsevier Ltd.A all rights reserved.
Aguiar D.M.,University of Texas Medical Branch |
Aguiar D.M.,Federal University of Mato Grosso |
Ziliani T.F.,Federal University of Mato Grosso |
Zhang X.,University of Texas Medical Branch |
And 17 more authors.
Ticks and Tick-borne Diseases | Year: 2014
A novel Ehrlichia genotype most closely related to E. canis was reported in North American cattle in 2010, and a similar agent was subsequently identified in the hemolymph of Brazilian Rhipicephalus (Boophilus) microplus ticks and isolated in 2012. The purpose of this study was to determine whether this or other novel ehrlichial agents naturally infect Brazilian cattle. Using PCR targeting the genus-conserved dsb gene, DNA from this novel ehrlichial agent in Brazilian cattle was detected. Attempts to isolate the organism in vitro were performed using DH82 cells, but morulae and ehrlichial DNA could only be detected for approximately one month. In order to further molecularly characterize the organism, PCR was performed using primers specific for multiple E. canis genes (dsb, rrs, and trp36). Sequence obtained from the conserved rrs and dsb genes demonstrated that the organism was 99-100% identical to the novel Ehrlichia genotypes previously reported in North American cattle (rrs gene) and Brazilian ticks (rrs and dsb genes). However, analysis of the trp36 gene revealed substantial strain diversity between these Ehrlichia genotypes strains, including divergent tandem repeat sequences. In order to obtain preliminary information on the potential pathogenicity of this ehrlichial agent and clinical course of infection, a calf was experimentally infected. The calf showed clinical signs of ehrlichiosis, including fever, depression, lethargy, thrombocytopenia, and morulae were observed in peripheral blood monocytes. This study reports a previously unrecognized disease-causing Ehrlichia sp. in Brazilian cattle that is consistent with the genotype previously described in North America cattle and ticks from Brazil. Hence, it is likely that this is the organism previously identified as Ehrlichia bovis in Brazil in 1982. Furthermore, we have concluded that strains of these Ehrlichia genotypes can be molecularly distinguished by the trp36 gene, which has been widely utilized to define E. canis strain diversity. © 2014 Elsevier GmbH.