title: Supplementing corn-soybean meal diets with microbial phytase linearly improves phytate phosphorus utilization by weanling pigs.
abstract: Two experiments were conducted with weanling pigs to determine the effectiveness of a dietary supplement of Aspergillus niger phytase in improving the availability of phytate-P in corn-soybean meal diets without supplemental inorganic P. Experiment 1 consisted of two P and Ca balance trials and two feeding trials. Twelve pigs (8.18 +/- .44 kg BW) were housed individually in stainless steel metabolism cages. Six pigs received 750 phytase units (PU)/g of basal diet and the other six pigs received the basal diet without supplemental phytase as control. In Exp. 2, 96 pigs (8.81 +/- .75 kg BW) were allotted to 16 partially slotted floor pens and their basal diets were supplemented with either 0, 250, 500, or 750 PU/g for 4 wk. Individual pig weights and pen feed consumption were measured weekly. Blood samples were taken from all pigs at the end of each trial in Exp. 1 and from three pigs per pen weekly in Exp. 2 to measure serum (plasma) inorganic P (P) and Ca concentrations and alkaline phosphatase (AP) activities. The results of Exp. 1 indicated that dietary phytase increased P retention by 50% (P < .0001) and decreased fecal P excretion by 42% (P < .0001). Pigs that received dietary phytase had serum P and Ca concentrations and serum AP activities that were nearly normal, whereas control pigs had values indicative of a moderate P deficiency. Favorable effects of phytase disappeared when the phytase was removed from the diet.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Department of Animal Science, Michigan State University, East Lansing 48824.
authors.forename: X G
authors.initials: XG
authors.lastname: Lei
authors.forename: P K
authors.initials: PK
authors.lastname: Ku
authors.forename: E R
authors.initials: ER
authors.lastname: Miller
authors.forename: M T
authors.initials: MT
authors.lastname: Yokoyama
mesh_terms: D010832:6-Phytase / Q000008:administration & dosage / Q000378:metabolism*; D000042:Absorption; D000469:Alkaline Phosphatase / Q000097:blood; D000821:Animal Feed; D000818:Animals; D001234:Aspergillus niger / Q000201:enzymology; D002118:Calcium / Q000097:blood; D002136:Calcium, Dietary / Q000008:administration & dosage / Q000493:pharmacokinetics; D004063:Digestion; D004435:Eating; D005260:Female; D008297:Male; D010758:Phosphorus / Q000097:blood; D016226:Phosphorus, Dietary / Q000008:administration & dosage / Q000493:pharmacokinetics*; D010833:Phytic Acid / Q000493:pharmacokinetics*; D011897:Random Allocation; D013025:Glycine max; D013552:Swine / Q000254:growth & development / Q000378:metabolism*; D014886:Weaning; D015430:Weight Gain; D003313:Zea mays
chemical_list: D002136:Calcium, Dietary; D016226:Phosphorus, Dietary; D010758:Phosphorus; D010833:Phytic Acid; D000469:Alkaline Phosphatase; D010832:6-Phytase; D002118:Calcium