Abstract Mature Single Comb White Leghorn roosters were used in two trials to measure the TMEn and true amino acid availability (TAAA) in canola seed, flax seed, canola meal, flax meal, soybean meal, barley, three mixtures of barley and canola seed, and three mixtures of barley and flax seed. The mixtures contained 80, 70, or 60% barley with the rest either canola or flax seed, respectively. The precision feeding method was used and each treatment was replicated three times. Excrement was collected 24 and 48 h after a weighed amount of the test ingredients was fed. It was observed that the TMEn of canola seed was .53 kcal/g higher than that of flax seed. Mixing barley with either canola or flax seed resulted in a product that was significantly (P .05). However, the availability of glutamate, valine, and isoleucine in the barley mixtures with canola seed was higher (P