This protein is poorer in lysine than soybean (5.5% vs. 6.3% of the crude protein) but is richer in sulphur-containing amino acids (sum of methionine + cysteine: 4.3% vs. 3% of the crude protein). Rapeseeds are small and contain about 18-21% hulls, and the oil meal contains about 30% hulls. Thus rapeseed meal has a relatively high fibre content, crude fibre being between 10-18% of DM, which is higher than the crude fibre content of all types of soybean meals, but lower than that of other oil meals such as sunflower meal. Its lignin content is also high (about 10% of DM), whereas the lignin content of soybean meal is usually lower than 1%. The low lysine and high fibre content tends to limit the use of rapeseed meal in monogastric and fish species. Feeding pigs and poultry with rapeseed meal as their only source of supplementary protein often results in lower animal performance.