The effects of supplementation of a novel bacterial 6-phytase on mineral digestibility and plasma minerals in lactating sows.
Pigs digest P in plant feedstuffs poorly because pigs do not produce sufficient endogenous phytase to hydrolyze P from phytate (inositol hexaphosphate). Supplementation of phytase to diets of piglets and grower-finisher pigs increased digestibility of minerals including P and Ca; however, data on phytase efficacy in lactating sows are scarce. Therefore, effects of adding a bacterial 6-phytase expressed in a strain of Aspergillus oryzae (Ronozyme HiPhos; DSM Nutritional Products, Basel, Switzerland) on apparent total tract digestibility (ATTD) of P and Ca was assessed in 45 lactating sows. Three diets were prepared: (i) positive control (PC; 0.52% available P), a regular sow diet containing inorganic P, (ii) negative control (NC; 0.20% available P) without inorganic P, and (iii) NC + 500 units of phytase/kg diet. Each diet was fed randomly to 15 sows for 21 d (from 5 d prior to farrowing to 15 d after farrowing). At day 15 after farrowing, ATTD of P did not differ between PC and NC. Phytase supplementation to NC increased (P < 0.05) ATTD of P from 34 to 46% compared to NC but did not affect (P > 0.05) ATTD of CP and Ca. On day 1 after farrowing, plasma P was 0.66 mmol/L lower (P < 0.05) in sows fed NC than PC. Phytase supplementation to NC increased (P < 0.05) plasma P by 0.40 mmol/L on day 1 but not on day 15 after farrowing. In conclusion, phytase supplementation increased P bioavailability in lactating sows.
University of Alberta, Edmonton, AB, Canada.
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Z
Nasir
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Broz
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RT
Zijlstra
D010832:6-Phytase / Q000235:genetics / Q000378:metabolism*; D000821:Animal Feed / Q000032:analysis; D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D004032:Diet / Q000662:veterinary; D019587:Dietary Supplements; D004063:Digestion / Q000187:drug effects*; D005260:Female; D007774:Lactation / Q000502:physiology*; D008903:Minerals / Q000097:blood; D013552:Swine / Q000097:blood* / Q000502:physiology*
D008903:Minerals; D010832:6-Phytase