Effect of increasing dietary canola meal inclusion on lactation performance, milk composition, and nutrient digestibility of lactating sows1

The aim was to determine the effects of increasing dietary canola meal in substitution for soybean meal in lactation sow diets. Forty-five sows with an average parity of 1.8 (SD = 0.83) were randomly assigned to 1 of 3 dietary treatments (n = 15) consisting of a corn-based control diet and 2 diets with 15% and 30% canola meal formulated by replacing soybean meal with canola meal. Diets were formulated to be similar in standardized ileal digestible AA content and NE value and to meet or exceed NRC (2012) nutrient recommendations for lactating sows. Sows were moved to farrowing on d 111 of gestation and fed the experimental diets until weaning on d 21. Sows were fed 3.0 kg/d from d 111 of gestation until parturition. After farrowing, feed was gradually increased through d 6 after which the diets were offered on an ad libitum basis until weaning. Sows were weighed and backfat thickness measured on d 111 of gestation and also on d 0, 7, and 21 postfarrowing. Litters were weighed on d 0, 7, and 21. Weaning to estrus interval in sows was also recorded. Blood and milk samples were collected 2 h postfeeding from sows on d 0, 7, and 21 and analyzed for plasma urea nitrogen (PUN) and milk composition. Fecal samples were collected on d 10, 11, and 12 postfarrowing to determine energy and nutrient digestibility. There were no dietary effects on lactation feed intake, sow BW and backfat change, weaning to estrus interval, and milk fat, protein, lactose, and urea composition. Also, there were no dietary effects on piglet ADG (P > 0.10). Sows fed diets containing 15% and 30% canola meal had lower (linear, P < 0.05) PUN values compared with those fed the control diet on d 0, 7, and 21 postfarrowing. Apparent total tract digestibility of DM, GE, CP, and P were reduced linearly (P < 0.05) with increasing canola meal inclusion. In conclusion, up to 30% canola meal in lactation diet can support satisfactory sow and suckling piglet performance.