Compara??o da toxicidade de Vicia villosa e Vicia sativa na alimenta??o de bovinos

• Autor(a) principal: Veronezi, Luciane Orbem
• Data de Publicação: 2016
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UFRRJ
• Texto Completo: https://tede.ufrrj.br/jspui/handle/jspui/2178
• topic: Experimental poisoning; Cows; Heifers; Vicia villosa; Vicia sativa; Intoxica??o experimental; Vacas; Novilhas; Medicina Veterin?ria

In this study the epidemiology, clinical signs, macroscopic and microscopic lesions related to spontaneous and experimental intoxication by Vicia villosa and the evaluation of the possible toxicity of Vicia villosa in cattle were characterized. The systematic granulomatous disease (SGD associated with vetch) was verified in 7 localities distributed in Paran?, Santa Catarina and Rio Grande do Sul States, with main feed that includes oats and/or ryegrass in association and V. villosa and/or ryegrass associated with Vicia sativa, and in lower quantity. All cattle that developed the disease were cows, lactating and Dutch. The SGD associated with vetch was reproduced in six lactating Dutch cows, by supplying green V. villosa in the trough and V. villosa and ryegrass pasture. In the other experimental groups (group 3, V. villosa / V. sativa/cows, grazing; group 4, V. sativa/cows, grazing; group 5, V. villosa/V. sativa/heifers and group 6, V. villosa/heifers, grazing) do not verified clinical and pathological alterations related to the SGD associated with vetch. Six cows developed the SGD, one cow presented a leigh clinical condition (group 2/cow 6/V. villosa, pasture), four cows developed a moderated clinical condition (group 1, cows 1 and 2/V. villosa/trough and group 2, cows 4 and 5/V. villosa, grazing), and just one cow presented a severe clinical condition (group 2, cow 3/V. villosa/pasture. V. villosa was toxic to cattle and produced a chronic granulomatous disease when ingested in amounts greater than 38.2 g/kg/day for 71 days, or in direct grazing for a period of more than 28 days The main clinical signs consisted of alopecia and cutaneous crusts, pruritus, fever, conjunctivitis, diarrhea, reduction of milk production and weight loss. Macroscopically, multiple white-grayish nodules were observed, specifically in the lymph nodes, kidneys and heart, and histology revealed a granulomatous infiltrate composed of macrophages, lymphocytes, giant cells, epithelioid cells, plasma cells and eosinophils. When ingested by young cattle, the V. villosa pasture, for a period of 68 days, do not produce clinical modifications. When ingested by cows with high milk yield, the V. sativa pasture, for a period of 78 days, does not produce chronic granulomatous disease. Ingestion of V. villosa for a long time led to low production rates, such as low milk production, low reproduction rates and predisposition to infection diseases. In the bromatological analysis, the presence of phytate, in low levels, in the samples of Vicia used in experimental works, in different phases of the culture was determined. The biochemical blood and feces results showing lower amounts of serum sinc and loss of Ca and Zn feces in animals poisoned by V. villosa, that developed granulomatous disease in severe and moderate conditions, possibly indicated the presence of a metabolic disorder in the pathogen of the disease.