The present study was carried out on 15 growing local bull calves of about 150-200 kg. live body weight and 10-12 months old to investigate the effect of substituting soyabean meal as concentrate feed mixture protein by Nigella sativa meal (NSM) at 0 . 60 and 100%. Animals were divided into 3 groups of 5 calves each. https://canadabrass.shop/product-category/collections/