ABSTRACT
Descreve-se um surto de distrofia muscular nutricional em ovinos no semi-árido Nordestino. Foram afetados animais de 3-4 meses de idade, da raça Dorper, pesando 30-40 kg. Os animais eram alimentados, à vontade, com leite, ração balanceada, capim Tifton e sal mineral. Dos 70 animais Dorper, 6 adoeceram e morreram em um período de 48 horas. Apresentaram temperatura, entre 40 e 41ºC, incoordenação com posterior paralisia e decúbito, depressão, prostração e diminuição dos reflexos pupilar e de ameaça, flacidez da língua e mandíbula, salivação, edema submandibular, dispnéia e aumento da freqüência cardíaca. A morte ocorreu após curso clínico de 6- 12 horas. Na necropsia de 3 animais, os músculos esqueléticos estavam de coloração pálida, o fígado estava aumentado de volume e de coloração amarelada, os gânglios parotídeos, submandibulares, retrofaríngeos, prescapulares e mediastínicos estavam aumentados de volume e avermelhados e os pulmões apresentavam áreas vermelhas. Na histologia havia necrose segmentar de todos os músculos examinados e congestão dos gânglios linfáticos e pulmão. Posteriormente mais três animais adoeceram, sendo tratado com oxitetraciclina e complexo vitamínico A,D e E. Desses 3 animais, 2 morreram e um sobreviveu. Na mesma fazenda havia e não adoeceram 20 ovinos da raça Santa Inês, da mesma idade que os animais afetados, que recebiam a mesma alimentação exceto o leite, e 900 ovinos de outras idades. A superalimentação em animais com rápido crescimento e o estresse causado pela restrição de água durantes 2 dias, para aumentar o consumo de leite, parecem ter sido fatores predisponentes para a ocorrência da doença. É possível, também, que algum dos minerais suplementados tenha antagonizado o Se presente na alimentação.
Subject(s)
Muscular Dystrophy, Animal/epidemiology , White Muscle Disease/epidemiology , White Muscle Disease/physiopathology , Sheep/anatomy & histologySubject(s)
Cytoskeletal Proteins/analysis , Laminin/analysis , Membrane Glycoproteins/analysis , Muscle, Skeletal/chemistry , Muscular Dystrophy, Animal/metabolism , Sheep Diseases/metabolism , Animals , Cytoskeletal Proteins/genetics , Cytoskeletal Proteins/metabolism , Disease Models, Animal , Female , Gene Expression Regulation , Humans , Laminin/genetics , Laminin/metabolism , Membrane Glycoproteins/genetics , Membrane Glycoproteins/metabolism , Muscle, Skeletal/metabolism , Muscular Dystrophy, Animal/congenital , Muscular Dystrophy, Animal/epidemiology , Sarcoglycans , Sarcolemma/chemistry , Sarcolemma/metabolism , Sheep , Sheep Diseases/congenital , Sheep Diseases/epidemiology , Western Australia/epidemiologyABSTRACT
White muscle disease appeared in lambs born of ewes in the zero grazing group during the course of a comparative fertility trial on ewes on various systems of husbandry. Analysis of the feed showed barely adequate selenium in the maize silage and a deficiency in the soil on which the high lysine maize was grown. Treatment of the lambs with a selenium/vitamin E injection rapidly controlled the condition. This deficiency may be more widespread than is presently realised.
Subject(s)
Disease Outbreaks/veterinary , Muscular Dystrophy, Animal/epidemiology , Sheep Diseases/epidemiology , White Muscle Disease/epidemiology , Animal Feed , Animals , Disease Outbreaks/epidemiology , Sheep , Sheep Diseases/etiology , South Africa , White Muscle Disease/etiology , White Muscle Disease/pathologyABSTRACT
Two experiments to study nutritional muscular dystrophy (N.M.D.) in calves were conducted in northern Ontario, where the disease is prevalent. In the first experiment, ninety Shorthorn cows were used. They were divided into three groups and fed the following forages during the winter of 1972-1973. Group I - Silage. Group II. - Heated-air-dried hay. Group III. - Field-dried hay. Chemical analysis of the forage during storage showed that the silage had a higher tocopherol content than the other two forages. This higher content had a direct effect on plasma tocopherol concentrations in the cows, since tocopherol levels were found to be higher in the group fed silage than in the other two groups. The highest mortality rate-eight dead calves-was in the group fed heated-air-dried hay; one calf died in each of the other two groups. Hence, it is evident that the severity of N.M.D. symptoms in calves is directly linked with the quantity of selenium or vitamin E ingested. The substances act synergistically to protect against the disease. In a second experiment, a herd of forty-seven Shorthorn cows, some of which had calves with N.N.D. and some of which had healthy offspring, were studied to measure the activity of serum creatine phosphokinase. The dams were found to have the same C.P.K., whether or not their calves suffered from N.M.D.
