The digestible energy value of canola oil for growing pigs as measured by level of inclusion

Abstract

Four levels (20, 40, 60, and 80 g kg −1) of canola oil were included in a cereal-based diet to determine the digestible energy of each diet. The diets were formulated to a constant protein to energy ratio. A metabolism experiment (Experiment 1) based on a repeated 4 × 4 Latin square using eight (Yorkshire × Landrace) pigs of initial weight 18 kg, and a growth trial (Experiment 2) in which 40 (Yorkshire × Landrace) 7 kg pigs, weaned at approximately 28 days, assigned to one of the four dietary treatments, with equal numbers of the two sexes per treatment were conducted. With increasing dietary fat the apparent digestible energy of the diets increased linearly ( P < 0.05 and P < 0.0001 for Experiments 1 and 2, respectively). Linear equations derived from regression analysis were used to calculate the apparent digestible energy value of canola oil (7.95 and 8.52 Mcal kg −1 for Experiments 1 and 2, respectively). The level of inclusion from 20 to 80 g kg −1 did not influence the digestible energy value. In Experiment 2, the average daily gain, feed intake, feed to gain and energy to gain did not differ with diet. Therefore, it can be concluded that the apparent digestible energy for canola oil for growing pigs of 20–30 kg, when given at an inclusion rate of between 20 and 80 g kg −1, is between 8.0 and 8.5 Mcal kg −1. This is higher than published digestible energy values for vegetable oils. Thus, canola oil is a good source of digestible energy for use in growing pig diets.