Nutritive value of rapeseed meals and rapeseed protein isolates

Defatted meals of two new varieties of rapeseed, Brassica napus, Erglu and Lesira, and protein isolates prepared therefrom, were fed to chicks that had been depleted of their embryonic protein reserve. First, the animals were fed at a 12% protein level, half of it from rapeseed meal, or a rapeseed protein isolate and, subsequently, at a 20% level, all of it from rapeseed products. Feed consumption, weight gain and protein efficiency ratio revealed better performance of the protein isolates as compared to the corresponding meals. This is attributed to the favorable amino acid patterns of these isolates and the absence of glucosinolates. Erglu meal, too, is eminently suitable as a supplement to chicken feed, whereas Lesira meal, although its amino acid pattern is adequate and similar to that of Erglu meal, showed detrimental effects, probably due to its high glucosinolate content.