Date of Graduation
Davis College of Agriculture, Natural Resources and Design
Animal and Nutritional Sciences
Joseph S Moritz
Kelley GS Wamsley
Grains commonly used in poultry diets contain phytic acid, a known anti-nutrient that binds dietary phosphorus rendering it unavailable for absorption also decreasing the digestibility of other nutrients. Phytic acid also increases mucin production and endogenous amino acid secretions causing a gut irritant effect which may decrease performance. An abundance of phytase literatures suggests that phytase enzymes can liberate bound phosphorus enhancing phytate phosphorus utilization and bone mineralization. Recently, the use of super-doses of phytase has been suggested to, not only liberate bound phosphorus, but to alleviate the gut irritant effect associated with phytate phosphorus. Therefore, an experiment was conducted at West Virginia University utilizing varying inclusions of a commercially available phytase product in broiler diets that varied in corn Distillers dried grains with solubles (DDGS) inclusion to assess feed manufacture and performance variables. 1,740 straight-run Hubbard x Cobb 500 broilers were placed on study for 38 days to evaluate live performance. Broilers (6/pen for starter, 2/pen for grower and finisher) were randomly selected following the conclusion of each growth phase and were euthanized for tibia excision to examine bone mineralization efficiency among broilers consuming differing experimental diets. The results revealed a phytase x formulation interaction demonstrating a 5 point feed conversion ratio (FCR) benefit when broilers consumed a diet devoid of DDGS and containing a super-dose of phytase when compared to broilers fed diets with no phytase or DDGS. Differences in bone mineralization were only apparent in the starter phase, which may have been marginal in non-phytate phosphorus, suggesting that a super-dose of phytase may alleviate the gut irritant effect of phytate phosphorus.;Additionally, improved pellet quality has been shown to improve live performance in broilers. Pellet binders may be utilized to improve pellet quality although there is a lack of nutritive pellet binders available. Spirulina algae has been suggested to contain pellet binding qualities, along with its remarkable amino acid profile and protein content. Therefore, a study was conducted at the West Virginia University pilot feed mill to explain the effects of varying inclusions of Spirulina algae when manufactured at varying conditioning temperatures. Two broiler diets were formulated to be similar in nutrient content. A diet containing 0% algae and a diet containing 10% algae were batched and blended to create 5 experimental diets with varying algae inclusions. Each diet was pelleted at 3 conditioning temperatures as a randomized complete block design. The results revealed algae x temperature interactions demonstrating that as algae inclusion and conditioning temperature increased pellet durability increased, but algae inclusion was more beneficial to pellet quality at lower conditioning temperatures. Algae inclusions in diets conditioned at low temperatures may maximize pellet durability and nutrient digestibility.
Boney, John W., "Evaluating the Inclusion of Phytase Super-dose in Various Broiler Diet Formulations and Novel Pellet Binders" (2014). Graduate Theses, Dissertations, and Problem Reports. 5233.