title: Phosphorus digestibility response of growing pigs to phytase supplementation of triticale distillers' dried grains with solubles.
abstract: An experiment was conducted in growing pigs to determine the true total-tract digestibility (TTTD) of P in triticale distillers' dried grains with solubles (DDGS) with or without phytase using the regression method. Six diets were formulated in a 3 × 2 factorial arrangement, including 3 levels of triticale DDGS (300, 400, or 500 g/kg) and phytase (0 or 500 phytase units [FTU]/kg of diet). A total of 48 barrows (initial BW 22.2 ± 1.3 kg) were assigned to the 6 diets in a randomized complete block design. There was a 5-d adjustment period followed by a 5-d total collection of feces. The results show that P intake, fecal P output, and digested P increased linearly ( < 0.01) with increasing level of DDGS in diets. There was a main effect ( < 0.001) of phytase on apparent total-tract digestibility (ATTD) of P. In diets without added phytase, the ATTD of P in triticale DDGS was 65.0, 67.7, and 63.2% for the diets with 300, 400, and 500 g/kg triticale DDGS, respectively; the corresponding values for diets with added phytase were 77.3, 76.3, and 75.7%. By regressing daily digested P against daily P intake, the TTTD of P was estimated at 75.4% for triticale DDGS or 81.1% with added phytase, respectively. In conclusion, the TTTD of P in triticale DDGS without supplemental phytase was 75.4%, and it was 81.1% in the presence of phytase at 500 FTU/kg of the diet, but the difference was not statistically significant. For triticale DDGS, the supplementation of 500 FTU/kg phytase in diet could increase the ATTD of P ( < 0.001) but not the TTTD of P.
authors.forename: P C
authors.initials: PC
authors.lastname: Xue
authors.forename: O
authors.initials: O
authors.lastname: Adeola
mesh_terms: D010832:6-Phytase / Q000008:administration & dosage / Q000494:pharmacology*; D000821:Animal Feed / Q000032:analysis; D000818:Animals; D004032:Diet / Q000662:veterinary; D019587:Dietary Supplements; D004063:Digestion / Q000187:drug effects*; D002523:Edible Grain; D005243:Feces / Q000737:chemistry; D008297:Male; D010758:Phosphorus / Q000032:analysis; D016226:Phosphorus, Dietary / Q000378:metabolism*; D012044:Regression Analysis; D013552:Swine / Q000254:growth & development* / Q000378:metabolism*; D000066889:Triticale / Q000737:chemistry / Q000378:metabolism*
chemical_list: D016226:Phosphorus, Dietary; D010758:Phosphorus; D010832:6-Phytase