Apparent digestibility of protein and amino acids in broiler chickens fed a corn-soybean diet supplemented with microbial phytase

• Published in: Poultry science Vol. 76; no. 12; pp. 1760 - 1769
• Main Authors: Sebastian, S, Touchburn, S.P, Chavez, E.R, Lague, P.C
• Format: Journal Article
• Language: English
• Published: England 01-12-1997
• Subjects: 6-Phytase - administration & dosage; 6-Phytase - metabolism; ACIDE AMINE; Aging - metabolism; Aging - physiology; AMINO ACIDS; Amino Acids - analysis; Amino Acids - metabolism; Amino Acids, Essential - analysis; Amino Acids, Essential - metabolism; AMINOACIDOS; Animals; BIOLOGICAL DIFFERENCES; Body Weight - drug effects; Body Weight - physiology; BROILER CHICKENS; CALCIO; CALCIUM; Calcium, Dietary - analysis; Calcium, Dietary - metabolism; Chickens - growth & development; Chickens - physiology; DIET; Diet - veterinary; DIETA; Dietary Proteins - metabolism; Dietary Supplements; DIFERENCIAS BIOLOGICAS; DIFFERENCE BIOLOGIQUE; DIGESTIBILIDAD; DIGESTIBILITE; DIGESTIBILITY; Digestion - drug effects; Digestion - physiology; Eating - drug effects; Eating - physiology; EFFICACITE ALIMENTAIRE; EFICIENCIA DE CONVERSION DEL PIENSO; FAECES; FECES; FECES COMPOSITION; FEED CONVERSION EFFICIENCY; FEED INTAKE; Female; FITASA; FOSFORO; GAIN DE POIDS; GANANCIA DE PESO; Glycine max - chemistry; Glycine max - metabolism; HECES; ILEUM; Ileum - metabolism; Ileum - physiology; INGESTION DE PIENSOS; INTESTIN; INTESTINES; INTESTINOS; LIVEWEIGHT GAIN; MAIS; MAIZ; MAIZE; Male; MINERAL NUTRIENTS; NUTRIENTES MINERALES; PHOSPHORE; PHOSPHORUS; Phosphorus, Dietary - analysis; Phosphorus, Dietary - metabolism; PHYTASE; POLLO DE ENGORDE; POULET DE CHAIR; PRISE ALIMENTAIRE (ANIMAUX); PROTEINAS; PROTEINE; PROTEINS; Random Allocation; REGIME ALIMENTAIRE; SEX; SEXE; SEXO; SOYBEAN MEAL; SOYBEAN OILMEAL; SUBSTANCE NUTRITIVE MINERALE; TORTAS DE SOJA; TOURTEAU DE SOJA; WEIGHT GAIN; Weight Gain - drug effects; Weight Gain - physiology; Zea mays - chemistry; Zea mays - metabolism
• ISSN: 0032-5791; 1525-3171
• DOI: 10.1093/ps/76.12.1760

The effect of microbial phytase supplementation on CP and amino acid (AA) digestibility was investigated in a 28-d trial using 360 sexed, day-old broiler chickens fed corn-soybean meal diets. The experimental design was a completely randomized one with a 3 X 2 factorial arrangement of treatments. The variables included P and Ca levels and phytase: P and Ca levels were: normal P-normal Ca [0.45% available P (Pa), 1.0% Ca], low P-normal Ca (0.35% Pa, 1.0% Ca), and low P-low Ca (0.35 Pa and 0.6% Ca); and phytase at 0 and 600 U/kg diet. Phytase supplementation increased body weight gain (P 0.014) and feed intake (P 0.004) at 19 d in male chickens; in females, phytase increased (P 0.012) only body weight gain at 19 d. The low P-normal Ca diet reduced (P 0.05) feed intake and body weight gain in both sexes at 7, 14, and 19 d, compared to the normal P-normal Ca diet; the reduction of Ca in the low P diet prevented the above depression, resulting in body weight gain and feed intake to a level comparable to that of the normal P-normal Ca diet. Microbial phytase supplementation had no effect (P 0.065) on the apparent ileal digestibility (AID) of CP or any AA except Met and Phe in male broiler chickens. In females, adding phytase increased the AID of all AA except Lys, Met, Phe, and Pro. The low P-normal Ca diet reduced (P 0.05) the AID of Phe, Asp, and Ser in male chickens and reduced the AID of all the AA except Met and Pro in females compared to the normal P-normal Ca diet. The reduction of Ca in the low P diet prevented the depression of the AID of the AA caused by the low P-normal Ca diet, resulting in AID of AA having a level comparable to that of the normal P-normal Ca diet in both sexes. Phytase supplementation did not have any effect (P 0.05) on apparent "fecal" digestibility (AFD) of CP or any of the AA in male chickens; however, in female chickens it increased the AFD of Thr, Asp, Glu, and Ser