Rapeseed meal and enzyme supplementation on growth performance and nutrient digestibility in pigs

The EU animal production relies on protein imports to satisfy the demand of the animal feed industry. However, these imports are subject of increasing concerns and the use of alternative EU protein sources is recommended. Rapeseed meal (RSM), a by-product of oil industry, contains large amounts of protein but also contains antinutritional factors (ANF) such as glucosinolates or a high fiber content that limit its use. Processing of RSM to eliminate ANF might increase its protein content resulting more attractive for animal feeding. The aim of this study is to evaluate the influence of a high-protein RSM in combination with enzyme supplementation of diets for growing pigs. A 2x3 factorial arrangement of diets containing conventional (35 % CP) or high-protein (40 % CP) RSM in combination with supplementation of protease or NSPase and protease enzymes was used. One hundred forty-four pigs were allocated into 12 blocks of body weight and sex, and housed by 2 in 72 pens. The trial lasted 6 weeks and faeces samples were collected during the 5th week and oven-dried for 72 h at 60° C before lab analysis. Productive performance and major nutrient digestibility parameters were used as response criteria. Data were analyzed using the GLM procedure of SAS. Body weight gain was not affected by the dietary treatments (NS). However, feed conversion ratio was improved (P<0.01) on pigs fed the high-protein RSM diets due to a reduction of feed intake (P<0.01). On the contrary, enzymes inclusion into diets did not affect productive performances (P˃0.05). Digestibility of dry matter, nitrogen or energy were not affected by the diet. Only fat digestibility was improved (P<0.01) due to high-protein RSM utilization. In conclusion, high-protein RSM improves feed efficiency of growing pigs and can positively contributes to reduce EU protein imports for animal feeding.