Date Full Report Received


Date Abstract Report Received



Primary Investigator:

The objective of this research was to measure the effects on energy and P digestibility of adding 4 levels of exogenous enzyme to corn, DDGS, HP DDG, and corn germ when fed to growing pigs. The 4 levels of phytase were 0, 500, 1000, and 1500 FTU per kg of diet. It was a further objective to develop regression equations for the inclusion of phytase in each ingredient, which will allow users to calculate the digestibility of P in the 4 ingredients regardless of the level of phytase in the diet. A broken line analysis was also conducted to identify the level of phytase in each ingredient that maximizes P digestibility.
Results of this research have considerable value to US swine producers because it allows producers to optimize the use of distillers co-products and take advantage of the high digestibility of P in some of the co-products from the ethanol industry. Our previous research has demonstrated that the digestibility of P in co-products that have been fermented is much greater than in non-fermented co-products and in corn. It is also established that the addition of exogenous phytase to diets improve P digestibility. We have also demonstrated that the combination of phytase and DDGS in diets fed to pigs results in a very high digestibility of P. However, there is no information on the optimum levels of phytase in diets containing fermented or non-fermented corn co-products and it is not known how much the inclusion of phytase and corn co-products can reduce the excretion of P in the manure from pigs. There is also no information on the effects of phytase on the digestibility of P in corn co-products other than DDGS.

The present research addressed these questions and for the first time provided data to the US swine industry that allow feed companies and producers to optimize the use of phytase in diets containing corn and corn co-products. By optimizing the utilization of P, diet costs will be reduced, which will lower production costs of pigs, and thus, improve the competitiveness of US pork. Results of this research also showed reduction in the excretion of P from the animals, which will allow producers to apply more manure per acre and thus reduce the costs associated with manure applications.

Results of this research can be implemented immediately so the savings to pork producers can be obtained without delay and without requiring producers to invest in additional technology on their operations.