Performance of growing-finishing pigs fed barley-based diets containing toasted or non-toasted canola meal

Abstract

Eighty crossbred pigs (28.7 ± 3.9 kg BW) were assigned to one of five dietary treatments in a factorial design experiment (sex × treatment). The control diet was formulated using barley and soybean meal, while four experimental diets were formulated with either toasted or non-toasted canola meal replacing either half or all of the soybean meal in the test diets. The total glucosinolate content of the non-toasted meal was more than 15-fold higher than the to asted meal (1.01 vs. 15.58 µmol g-1). The principal glucosinolates in the non-toasted meal were 3-butenyl (3.05 µmol g-1), 2-OH-3-butenyl (5.47 µmol g-1) and 4-OH-3-methylindoyl (4.68 µmol g-1). Digestibility coefficients for dry matter, crude protein, and gross energy were significantly (P < 0.05) lower for the toasted and non-toasted canola meal diets compared with the soybean meal diet. There were no significant differences (P > 0.05) in digestibility coefficients between the two canola meals. Digestibility coefficients were higher (P < 0.05) for pigs fed the diets in which canola meal supplied only 50% of the supplementary protein compared with diets in which 100% of the supplementary protein was supplied by canola meal. Pigs fed toasted canola meal had similar weight gain, feed intake and feed conversion (P > 0.05) as pigs fed soybean meal while pigs fed non-toasted canola meal had lower weight gain and feed intake (P < 0.05) than pigs fed soybean meal. Feed conversion was unaffected by dietary treatment (P > 0.05). There were no significant effects (P < 0.05) due to diet on any carcass trait. The overall results of this experiment indicate that omitting the desolventization/toasting procedure from the process involved in the production of canola meal did not result in an improvement in the performance of pigs fed diets containing canola meal. Key words: Pigs, canola meal, performance, digestibility, carcass, toasting