RESUMO
In a fattening experiment with rapeseed meals produced by different techniques (cf. Part I) on broiler chickens, each experimental ration contained 10% of a variant rapeseed meal. The thyroid glands of the broiler chickens (allotted to 8 groups according to their diets) were examined for mass gain and submitted to various histopathological, biochemical and morphometric procedures. The variants of rapeseed meal applied to the animals in the groups IV, III and I have been found to be toxic. In contrast, the effects of the other variants of rapeseed meal on the morphology of the thyroid gland have been negligible.
Assuntos
Brassica , Galinhas/metabolismo , Bócio/etiologia , Intoxicação por Plantas/complicações , Animais , Brassica/genética , Manipulação de Alimentos , Variação Genética , Fígado/patologia , Tamanho do Órgão , Glândula Tireoide/patologiaRESUMO
With regard to studies on production process variants designed to improve the nutritive value of rapeseed meal, the authors describe the principles underlying the modified diffusion extraction procedures used (with and without rapeseed husking). Furthermore, they briefly outline the chemical methods applied to the determination of the nutrient composition and glucosinolate content of rapeseed meal variants as well as the methodology of their feeding and nitrogen balance experiments on growing albino rats and broilers. The results obtained with 13 analytical variants and 8 biological variants confirm once more the beneficial nutritive effects obtained with the reduction of the glucosinolate content of rapeseed meal in monogastric animal species. However, these results do not permit to appraise unequivocally the repercussion of rapeseed husking on the diminution of the content of paraplastic substances in rapeseed meal. The diffusion techniques used for reducing the glucosinolate content in rapeseed meal have been found to be effective.