Comparison of Natuphos and Phyzyme as Phytase Sources for Commercial Layers Fed Corn-Soy Diet

Abstract

The objective of this experiment was to compare the effects of 2 sources of phytase on performance of commercial Leghorns fed corn-soy diets. Seven diets were fed to Hy-line W-36 hens (n = 840; 8 replicates of 15 hens per treatment) from 21 to 33 wk of age. The treatments consisted of a control diet containing 0.38% nonphytate P (NPP) and a 2 x 3 factorial arrangement of 2 dietary NPP concentrations (0.11 and 0.26%) with 2 phytase sources [Natuphos (BASF, Mt. Olive, NJ) and Phyzyme (Danisco Animal Nutrition, Carol Stream, IL)] and without phytase. Dietary NPP had significant effects on feed intake, NPP intake, total P intake, egg production, egg weight, egg mass, egg specific gravity, and excreta P. The addition of Phyzyme or Natuphos significantly increased egg production and egg mass of hens fed the P-deficient diet (0.11% NPP) to levels that were similar to hens fed the control diet containing 0.38% NPP. Feed intake of hens fed the diets supplemented with Phyzyme or Natuphos was significantly less than that of hens fed the control diet containing 0.38% NPP. Phyzyme or Natuphos supplementation in the diets containing 0.11% NPP had significantly reduced excreta P of the control diet (approximately 58 and 54%, respectively) with no adverse effect on egg production and egg mass. There were no significant differences in feed intake, NPP intake, total P intake, egg production, egg weight, egg mass, feed conversion, egg specific gravity, mortality, BW, and excreta P between the diets supplemented with Natuphos and the diets supplemented with Phyzyme. In conclusion, Phyzyme had the same positive effects on performance of commercial Leghorns fed corn-soy diets as Natuphos.

Reduction of the nutritional values of diets for hens through supplementation with phytase

“…The results of production and egg mass in relation to the level of available phosphorus were improved with the addition of phytase at 600 FTU, which agrees with the results already reported by Wu et al (2006) when they found an increase in production and egg mass of hens fed deficient-in-P diets (0.11% available P) supplemented with 300 UF/kg, reaching values similar to those birds fed control diet (0.38% available P).…”

“…In contrast, Wu et al (2006) comments on his findings that the reduction of available phosphorus in the diet caused a reduction in feed intake, but when phytase was added to the experimental diets, consumption was improved, although it had been placed below the control diet.…”

Relação cálcio:fósforo disponível e níveis de fitase para poedeiras semipesadas no primeiro e segundo ciclos de postura

“…Keshavarz (2003), no entanto, observaram que houve redução no consumo de ração quando as aves receberam dieta com baixos teores de fósforo disponível (0,2 e 0,1%) e que o consumo foi restabelecido com a suplementação de fitase na ração (150 ou 300 UF). Similarmente, Wu et al (2006) observaram que a redução do fósforo disponível da dieta (de 0,38% para 0,26 e 0,11%) provocou redução no consumo de ração, mas que, quando a fitase foi adicionada às rações, o consumo melhorou, embora ainda tenha ficado abaixo dos valores obtidos com a dieta controle.…”

“…Entretanto, a suplementação das dietas com fósforo inorgânico, além do alto custo, pode ocasionar problemas ambientais (Wu et al, 2006). Em áreas com alta densidade de criação de aves comerciais, o fósforo presente nas excretas apresenta elevado potencial de poluição (Smith et al, 2001) e pode prejudicar a qualidade do solo e da água.…”

“…Com a suplementação das dietas com fitase exógena, os níveis de fósforo total das dietas podem ser reduzidos, a eficiência como o fósforo é retido é melhorada e sua excreção no meio ambiente é reduzida (Wu et al, 2006;Plumstead et al, 2007). Borrmann et al (2001), em pesquisa com poedeiras Hy Line durante o segundo ciclo de postura, recomendaram 0,36 de fósforo disponível para a dieta suplementada e 0,40% para a não suplementada com fitase (300 UF).…”