The objective of this study was to evaluate a commercial feed enzyme product (Natugrain 33-L; BASF Corporation, Ludwigshafen, Germany) used mainly in poultry diets for use in ruminant diets. The product contained mainly beta-glucanase, xylanase, and endocellulase activities. The study was conducted as a double 3 x 3 Latin square design with six lactating dairy cows (84 +/- 12 DIM) to measure intake, chewing activities, total tract digestion, and milk production. An additional three cows fitted with ruminal cannulae were used to measure dietary effects on ruminal fermentation and in sacco digestion characteristics. Cows received a diet consisting of 45% forage containing 0, 1.22, or 3.67 L of enzyme product/tonne of total mixed ration (DM basis). Using a low or high concentration of enzyme supplementation increased feed intake, but total tract digestibility only increased with the low concentration of enzyme. As a result, intake of digestible nutrients was increased to a greater extent for cows fed the low concentration than for cows fed the high concentration. Because the cows used in this experiment were in positive energy balance, increased intake of digestible energy due to enzyme supplementation did not increase milk yield or milk component yield. Further research is necessary to determine the mechanism by which adding a fibrolytic enzyme mixture enhanced intake, but only increased feed digestion when used at a low level.

An experiment employing a factorial arrangement of two levels of Ca, two levels of available P (AP), and three levels of phytase enzyme was carried out with 360 ISA White layers from 18 to 67 wk of age. The Ca levels were maintained at 3.7 and 4.0% throughout the experiment. The AP levels were 0.2 and 0.4% for the high and low treatments until 55 wk of age and were reduced to 0.11 and 0.22% thereafter. Phytase enzyme levels were 0, 250, and 500 phytase units (FTU)/kg of feed. In the period before Week 55, either level of AP was likely adequate for maximum production. However, when lower levels of AP were fed after this time, low AP was associated with reduced BW and egg production, and enzyme supplementation was able to compensate for low AP. In this period, high AP and the highest level of phytase produced negative effects on BW, egg weight, and the feed conversion ratio. The ratio of Ca to AP was important; shell quality was best with high or low levels of both. With high levels of Ca, enzyme supplementation compensated for low levels of AP and overcompensated with a high level of AP. These effects were reduced or absent with low levels of Ca. It is clear from this study that phytase enzyme can compensate for low levels of AP in diets based on corn and soybean meal, but that the optimum level of supplementation depends as well on the Ca level.

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...

Scott, T. A., Kampen, R. and Silversides, F. G. 2000. The effect of phosphorus, phytase enzyme, and calcium on the performance of layers fed wheat-based diets. Can. J. Anim. Sci. 80: [183][184][185][186][187][188][189][190]. A trial was performed to test the effects of two levels of Ca (3.7 and 4.0%), two levels of available P (0.2 and 0.4% until 55 wk, 0.11 and 0.22% from 55 to 67 wk), and three levels of phytase enzyme (0, 250 and 500 FTU kg -1 ) on the performance of laying hens fed diets based on wheat and soybean meal. Phytase supplementation had only small effects, likely because the endogenous phytase in the wheat liberated sufficient phytate-bound P to compensate for only marginally deficient levels. In contrast to what has been found with corn-based rations, there were no negative effects of high levels of AP or of enzyme, suggesting that the effect of exogenous phytase was more complex than a simple liberation of phytate P. Endogenous phytase should be considered when formulating rations based on wheat.Key words: Phytase, layers, wheat, phosphorus, calcium Scott, T. A., Kampen, R. et Silversides, F. G. 2000. L'effet du phosphore, de l'enzyme phytase et du calcium sur les performances des pondeuses alimentées avec des rations à base de blé. Can. J. Anim. Sci. 80: [183][184][185][186][187][188][189][190]. Un essai a examiné les effets de deux niveaux de Ca, (3.7 et 4.0%), deux niveaux de P disponible (0.2 et 0.4% jusqu'au 55 semaines, 0.11 et 0.22% par la suite) et trois niveaux d'enzyme phytase (0, 250 and 500 FTU kg -1 ) sur les performances des poules pondeuses alimentées avec des rations à base de blé et de tourteau de soya. La supplémentation avec le phytase a eu peu d'effet, probablement en raison d'une libération suffisante de P des phytates par des phytases endogènes dans une situation où les concentrations de P alimentaires étaient déjà presque adéquates. Il n'y a pas eu d'effet négatif des concentrations élevés de P disponible ou d'enzyme, ce qui suggère que l'effet de phytase exogène est plus complexe que la simple libération du P lié aux phytates. La contribution des phytases endogènes devrait être considérée lors de la formulation de rations à base de blé. Mots clés:Phytase, pondeuses, blé, phosphore, calcium Phytates, the salts of phytic acid, are the main storage form of P in plants Pallauf and Rimbach 1997), and render the P relatively unavailable to monogastric animals. Even with adequate total P in the feedstuffs, inorganic P is usually added to poultry diets, and undigested P is excreted in the manure. In some countries, legislation restricting the application of P and N to the land limits animal production.Phytates are hydrolyzed by the enzyme phytase to inositol and phosphoric acid, making the P available to the animal (Liu et al. 1998). Some cereals contain endogenous phytase activity, with wheat having moderate amounts , and there may be phytase activity in the small intestine of chickens (Maenz and Classen 1998). Phytase can also be isolated from microorganisms such as Aspergillus...