Efficacy of Phytases on Egg Production and Nutrient Digestibility in Layers Fed Reduced Phosphorus Diets

Abstract

The effects of phytases on the performance of layers and the ileal nutrient digestibility of corn-, soybean-, and by-product meal-based diets were assessed with 320 Hy-Line brown layers from 23 to 28 wk of age. Layers were grouped randomly into 5 treatments, with 8 replicates per treatment and 8 layers per replicate. The 5 diets consisted of a positive control diet with adequate Ca (3.30%), total P (0.50%), and nonphytate P (NPP; 0.28%), and a negative control diet with Ca reduced by 0.12%, total P reduced by 0.14%, NPP reduced by 0.13%, and 3 phytases (phytase A derived from Aspergillus niger, and phytases B and C derived from Escherichia coli) supplemented at 300 phytase units/kg of feed, respectively. Egg production and feed intake were recorded daily, and eggshell quality and ileal nutrient digestibility were measured at the end of a 6-wk feeding period. The results revealed that the reduction of Ca and P from the positive control diet significantly depressed feed intake, egg mass, eggshell hardness, and the digestibility of N, Ca, P, and amino acids (P < 0.05). Phytase supplementation in the negative control diet improved the digestibility of P and Ca by 11.08 and 9.81% (P < 0.05), respectively, whereas it improved the digestibility of amino acids by 2 to 8% (P < 0.05). However, the digestibility of most amino acids was not restored to the levels of the positive control diet by the application of phytases. Supplementing phytases in the negative control diet improved the rate of lay, egg mass, and egshell quality to the levels of birds fed the positive control diet. These results suggest that supplementing phytases can improve the digestibility not only of Ca and P, but also of amino acids in layers fed a corn-, soybean-, and by-product-based diet.

Efficacy of different levels of <i>Escherichia coli</i> phytase in hens fed maize-soyabean meal based diets with a decreased non-phytate phosphorus content

“…The phytase was effective even at the lowest concentration, which shows that the effect was not dose-dependent. It is in agreement with other researchers, who also obtained significantly lower egg production in P deficient treatments (Boling et al, 2000;Augspurger et al, 2007;Liu et al, 2007).…”

“…Phosphorus deficiency in laying hens is known to reduce feed consumption. In experiments of some authors (Jeroch and Peter, 1994;Augspurger et al, 2007;Liu et al, 2007) a significant decrease in feed intake in hens fed diets based on maize as a grain source that were not supplemented with dietary phytase was obtained, in case the NPP content ranged from 1.0 to 1.5 g/kg and it was substantially lower than recommended by the NRC (1994). Different results were reported by Vogt (1992) who demonstrated that a maize-soyabean diet containing only 1.2 g NPP/kg had no negative influence on feed intake in layers.…”

“…the new 6-phytase derived from Escherichia coli. The utilization of phosphorus contained in maize may be increased if diets are supplemented with microbial E. coli phytase (Wu et al, 2006;Augspurger et al, 2007;Liu et al, 2007;Hughes et al, 2008). In Poland, the effect of Escherichia coli phytase (ECP) supplementation on performance parameters has been studied in broilers and young turkeys (Kozłowski et al, 2009(Kozłowski et al, , 2010a, but not in laying hens.…”

Sunflower Meal and Supplementation of an Enzyme Complex in Layer Diets

“…Sunflower meal is rich in fiber and phytic acid, and therefore, a positive effect with the addition of the enzyme complex in the diets was expected; however, no such effect was verified in the present experiment. Liu et al (2007) and Viana et al (2009) also verified that the addition of phytase to diets with reduced nutrient levels did not improve egg production, egg weight, or feed conversion per dozen eggs of layers. The results of these authors were very similar to those found in the present study, where no influence of enzyme complex on those parameters were detected.…”

<b>Intestinal carbohydrase activity and sodium-glucose transporter expression in layers fed diets containing wheat and rice brans supplemented with phytase

“…The confirmation that stated dietary phytate inhibits sugar digestion and blood glucose in rats (Dilworth et al, 2004) and mice (Lee et al, 2006) resulted in this assumption that anti-nutritional factors capable of altering nutrient utilization might regulate associated gene expression (Liu et al, 2008b). Many studies have shown the effectiveness of phytase supplementation to improve the digestibility of phytate-bound P in poultry diets as well as reducing P excretion (Tangendjaja, Chung, & Broz, 2002) Several experiments have reported the efficacy of microbial phytase in laying hens and broilers diet (Mathlouthi, Larbier, Mohamed, & Lessire, 2002;Panda, Rao, Raju, & Bhanja, 2005;Cowieson & Ravindran, 2007;Liu et al, 2007;Liu et al, 2008a).…”