Allzyme® Spectrum supplementation improves apparent ileal phosphorus digestibility and retention in older laying hens

Phosphorus (P) is required by laying hens for various biological functions, and it is usually provided in excess, in a readily digestible inorganic form in diet formulations. By adding enzymes to diets, the availability of phytate-bound P can be increased, allowing for the reduced inclusion of inorganic P in the diet formulation. The following study was conducted to examine the effect of a natural enzyme complex that contains phytase and xylanase on P digestibility in laying hens. Novogen Brown Classic layers (n=314, 95 weeks of age, approximately 14 weeks into second lay) were fed one of two diets; either a basal control diet or a the basal control diet plus a natural mixed-enzyme product (Allzyme® Spectrum; ASC, Alltech Inc, KY, USA) containing phytase (1000 SPU/g) and xylanase (7,500 EPU/g). The experimental diets were provided for 15 days, and excreta was collected from each pen at day 13–15 of the trial to determine total tract retention and apparent ileal digestibility of P and gross energy. At the end of the trial, birds were euthanised and ileal contents were collected. Productivity parameters, including egg production and feed conversion ratio, were recorded over the course of the study. The amount of P in the excreta from birds in the control group was significantly higher than the ASC enzyme-supplemented group. Both P retention, its ileal digestibility and gross energy digestion (ileum and total tract) were significantly higher in the ASC enzyme-supplemented birds. This study showed that the ASC enzyme supplement can improve the total retention and ileal digestibility of P and gross energy in older layers.