Effects on chick growth of adding various non‐protein nitrogen sources or dried autoclaved poultry manure to diets containing crystalline essential amino acids

Synopsis Female broiler chicks were offered semi‐purified diets containing crystalline essential amino acids, including proline, supplemented with various nitrogen sources. Individual final body weights, food consumption and food conversion efficiencies (FCE) were measured. In the first experiment 70 1‐d‐old chicks were given one of seven diets for 21 d; basal (1A) or basal plus: 12% l‐glutamic acid (1B), 17.05% monoammonium citrate (1C), 9.23% diammonium citrate (1D), 6.61% triammonium citrate (TAC) (1E), 2.45% urea (1F) or 4.05% triammonium phosphate and 12.56% calcium lactate (1G). Using body weight at 21 d and FGE as measures of the effectiveness of the various nitrogen sources the orders were 1E (171 g), 1B (154 g) > 1D (131 g), 1G (123 g), 1F (118 g) >basal (89 g) >1C (66 g), (P < 0.05) and 1B (0.456), 1E (0.420) >1G (0.346), 1F (0.329), 1D (0.319) > basal (0.269) > 1C (0.192), (P < 0.05), respectively. In the second experiment 70 7‐d‐old chicks were offered one of seven diets for 14 d; basal (2A) or basal plus 12% l‐glutamic acid (2B), 8.0% l‐glutamic acid and 2.21% TAC (2C), 4.0% L‐glutamic acid and 4.42% TAC (2D), 6.61% TAC (2E), 3.43% uric acid (2F) or 20.09% dried autoclaved poultry manure (2G). When the final body weights at 21 d and FCE were placed into a rank order, the degrees of effectiveness were: 2C (250 g), 2B (245 g), 2D (244 g), 2G (240 g) > 2E (206 g) > basal (165 g), 2F (150 g) (P < 0.045) and 2B (0.471), 2G (0.451), 2C (0.445), 2D (0.436) >2E (0.399) > basal (0.314) >2F (0.243) (P < 0.05), respectively. The results for diets 2B, 2C, 2D and 2E appear to indicate that 4% glutamic acid is required for maximal chick growth with these crystalline amino acid diets.