Effect of Carbohydrate Source and Addition Canola Seed on Growth Performance and Nutrient Digestibility of Lambs

The objective of this study was to investigate effects of partial replacement of starch with neutral detergent soluble fiber with or without roasted canola seed as a fat source, and possible interactions on apparent digestibility and growth performance of growing lambs. For this purpose, 24 male lambs were used in a completely randomized design with a 2×2 factorial arrangement of treatments. Dietary treatments were 1- starch from barley, 2- starch from barley with roasted canola seed, 3- soluble fiber from beet pulp, and 4- soluble fiber from beet pulp with roasted canola seed. The experimental period was 84 days and forage:concentrate ratio was 10:90 for all diets. Treatments had no significant effect on the dry matter intake, feed conversion ratio, apparent digestibility of protein and organic matter (p>0.05). High starch diets compared with high soluble fiber diets caused a significant decrease in the digestibility of dry matter, organic matter, ADF and NDF (p<0.01). Canola seed addition to the diets significantly decreased ADF and NDF digestibility (p<0.01). The carbohydrate source by canola seed interaction was significant for weight gain and rumen pH (p<0.01) indicating that addition of canola seed to high starch diet increased weight gain and rumen pH more dramatically in comparison with soluble fiber diet (p