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Poultry, particularly growing chickens, are sensitive to the beta-glucans in barley. Beta-glucans form gels in the digestive tract of birds that are not broken down because of the lack of appropriate enzymes and the rapid rate of passage in poultry. Without addition of beta-glucanases to the feed, barley-based diets have been associated with reduced levels of available energy and with wet droppings, pasty vents, and wet litter.
However, adding beta-glucanases to diets fed to poultry can effectively eliminate the problems with wet, gummy droppings while increasing the availability of dietary energy and reducing the effective variation in energy content.
The discussions that follow assume that enzymes have been added to the diet at levels recommended by the manufacturer of the appropriate product.