Effects of algae incorporation into broiler starter diet formulations on nutrient digestibility and 3 to 21 d bird performance

Algae, a human supplement and alternative fuel source, has potential as a feed ingredient for poultry. Three studies were conducted with the following objectives: determine digestible nutrient values for a commercially availableSpirulina algae (Study 1), formulate and pellet a practical broiler starter diet using these data (Study 2), and assess feeding diet formulations with varying levels of algae on Hubbard X Cobb 500 broiler performance and apparent ileal amino acid digestibility (AIAAD; Study 3).Spirulina algae TMEn (2,839 kcal/kg) and true amino acid digestibility (TAAD) values (2.10, 1.07, 0.42, and 1.97% lysine, methionine, cysteine, and threonine, respectively) from Study 1 were used to formulate a practical broiler starter diet containing 21% algae. A diet containing 0% algae was also formulated. Both diets were pelleted, ground, and mixed at different ratios to create diets containing 6, 11, and 16% algae. The 21% algae diet resulted in a nominally lower production rate and an increase in hot pellet temperature and pellet durability compared to the 0% algae diet. Diets containing up to 16% algae resulted in statistically similar ending parameter compared birds fed the 0% algae diet: ending bird weight (EBW), live weight gain, and feed intake (P > 0.05). The 16% algae diet resulted in the highest level of digestible cysteine and lysine (P < 0.0001). All diets containing algae resulted in higher digestible methionine values compared to the 0% algae diet (P < 0.0001). Descriptive feed manufacture, performance, and AIAAD data demonstrated value in algae incorporation into practical diet formulations.