The effect of adding exogenous phytase to nutrient-reduced corn- and wheat-based diets on performance and egg quality of two strains of laying hens

Abstract

Scott, T. A., Kampen, R. and Silversides F. G. 2001. The effect of adding exogenous phytase to nutrient-reduced corn-and wheat-based diets on performance and egg quality of two strains of laying hens. Can. J. Anim. Sci. 81: 393-401. A laying trial was conducted in which ISA-Brown and ISA-White hens were fed diets based on corn or wheat that had been pelleted to eliminate endogenous phytase. Control diets were formulated to contain adequate levels of all nutrients. Nutrient-reduced diets were formulated to account for nutrients released by the phytase. To formulate these diets, phytase was entered into the matrix with a value, on a weight basis, of 1,173% for CP (60.5% for lys, 29.4% for met plus cys, 40.0% for thr), 39 900 kcal kg -1 for AME, 666% for Ca, and 333% for available P. A negative control diet was based on the modified formulation but did not include phytase. Differences between diets were observed for tibia ash, and Ca and P in the ash, as well as for BW and measures of egg quality. Egg production likely provided the best measure of the adequacy of P nutrition. In the final period of production, feed intake and egg production of hens fed the nutrient-reduced corn-based diet without enzyme was lower (P < 0.05) than that of hens on the control diet. Egg production of hens fed the nutrient-reduced diet with phytase was similar to that of hens fed the control diet, showing that inclusion of phytase permits formulation of corn-based diets with reduced levels of energy, CP, Ca, and P. No major effect of diet was seen for the hens fed wheat-based diets indicating that the formulation changes used may not have been appropriate for evaluating a response to exogenous phytase in wheat-based diets. Dans un essai, des poules pondeuses ISA-Brown et ISA White ont été nourries avec des rations à base de maïs ou de blé traitées pour éliminer le phytase endogène. Des rations de contrôl ont été formulées pour contenir des niveaux adéquats de tous les nutriments et la formulation des autres rations était modifiée pour inclure des valeurs pour l'azote brute, l'énergie metabolizable, le Ca et le P qui sont libérées des ingrédients de l'aliment par l'action de l'enzyme phytase. Dans cette formulation, l'enzyme avait une valeur, sur le base de poids, de 1,173% pour l'azote brute (60.5% pour lys, 29.4% pour met plus cys, 40.0% pour thr), 39 900 kcal kg -1 pour l'energie metabolizable apparent, 666% pour Ca et 333% pour P disponible. Un contrôle négatif utilisait la modification de formulation mais n'incluais pas l'enzyme. Il y avait des différences entre les rations pour les cendres de tibia, pour les niveaux de Ca et P dans les cendres, pour le poids corporel et pour les mesures de qualité des oeufs. La production des oeufs était peut-être la meillure mesure si les niveaux de P étaient adéquats. Dans la période finale de production, la consommation de moulée et la production des oeufs des poules alimentées avec les rations modifiées à base de maïs étaient réduites (P < 0.05), mais l'enzyme a éliminé ces effets, ce qui a dém...

Intestinal and total tract phytate digestibility and phytase activity in the digestive tract of hens fed a wheat-maize-soyabean diet

“…In ISA Brown hens fed a maize-based diet with P and Ca at 6.4 and 40.2 g-kg 1 (without exogenous phytase), the retention of P and Ca was 43.8 and 66.7%, respectively. The corresponding P and Ca retention values in hens fed a wheat-based diet were 39.2 and 62.8% (Scott et al, 2001). In both of the digestibility trials performed in the current study, the intestinal retention of P was significantly higher than the total tract retention.…”

Effects of supplementation of multi-enzyme and multi-species probiotic on production performance, egg quality, cholesterol level and immune system in laying hens

“…The effect of enzymes supplementation on egg weight was due to a difference in Haugh unit rather than shell or yolk weight. Scott et al (2001) also found that phytase increased albumen height (one parameter for determination of Haugh unit) in corn-based diet; the factors contributing to albumen height are not well understood.…”

“…The use of phytase may release these essential nutrients thereby improving nutritional value of poultry diet, which resulted positively on productive performance of laying hens (Panda et al 2005). The response to the enzyme is not straightforward since it is relatively variable, depending upon factors such as bird age and type (Scott et al 2001), cereal grains, level and geographical locations (Chesson 2001), enzyme inclusion level (Karimi et al 2000) and feed processing (Svihus et al 2000).…”

PERFORMANCE OF LAYER HEN FED FERMENTED Jatropha Curcas L. MEAL SUPPLEMENTED WITH CELLULASE AND PHYTASE ENZYME

“…Phytate binds nutrients in addition to P, and the addition of phytase to feed caused the release of these nutrients and allows their absorption by the bird. Nutrients affected by phytates include minerals and protein (Ravindran et al, 1995;Selle et al, 2000), and phytase had been shown to affect the release of energy (Scott et al, 2001).…”