Rapeseed ( Brassica napus L.) and its prospective usage in poultry diet

A recent trend in the world's crop production is an intensified cultivation of oil-yielding crops, particularly rape ( Brassica napus ), as a source of vegetable oils and valuable protein for animal nutrition. Rape is especially promising crop for climatic and soil conditions of the Russian Federation as it can be grown almost all over the country. Energy content in rape is 1.7 to 2.0 times as much as in cereals, and 1.3 to 1.7 times as much as in legumes. Amino acid composition in rape proteins is well-balanced, and the lysine level is almost similar to that in soy, while the methionine, cystine, Ca and P levels are much higher. In animal farming and poultry the rape seeds, as well as rape oilcake, meal and oil are used. In rape seeds the fat content is 40 %, the protein level reaches 23 % and cellulose amounts to 4 %. However, their use in hen's feeding is limited due to poor digestibility of seed shells and specific composition. In rape oil the level of unsaturated fat acids is high, i.e. 60.0-70.0 % for oleic acid, 23.3 % for linoleic acid and 10.5 % for linolenic acid which can regulate biosynthesis of prostaglandins thus effecting positively the reproductive function. Biological, energy and protein value of rape seed meal is high and similar to that of high-protein feed-stuff of animal origin. The rape meal is rich in choline, biotin, folic acid, riboflavin, thiamin and minerals compared to soy though some of these elements are less available. The rape oilcake contains fats at 8.75 %, cellulose at 12.0 % and proteins at 32.0 % on the average. These proteins are enriched with irreplaceable amino acids, and the lysine and S-containing amino acids levels amount to 5.7 and 5.0 %, respectively. Anti-nutritive compounds including erucic acid and glucosinolates are the factors limiting use of rapeseed and related products in animal nutrition. In the article the methods for improving nutritive value of rapeseed products are discussed, including genetic selection of rape, thermal processing and supplementation of diets with enzyme preparations. Classification of rape cultivars is considered with regard to fatty acids and glucosinolates content in seeds («++», «0+», «+0», «00», «000»). Supplementation of broiler diets with rapeseed cake containing 0.41 % of isothiocyanates and 0.25 % of erucic acid together with a designed enzyme preparation MEC-CP-4 (Russia) is proposed as an effective feeding technology. In poultry this additive allows to use fodder containing 7.5; 10.0 and 15.0 % of rapeseed oilcake in case it is supplemented with 500, 750 and 1000 ppm MEC-CP-4, respectively.