| dc.description.abstract | The objective of this research was to evaluate the effects of a corn expressed phytase and glucanase enzyme on performance, bone ash response, apparent metabolizable energy and apparent ileal digestibility at varying inclusion rates. Experiment one consisted of a standard energy, Ca, and available Phosphorus (aP) level diet positive control and a -0.15% Ca and aP reduced negative control. Dietary treatments consisted of either a high (PY1203) or a low (PY203) specific activity corn expressed phytase at various inclusion rates (0.175 kg/t, 0.5 kg/t, 1.0 kg/t, 2.0 kg/t, and 3.0 kg/t). Results from this study showed that FCR was maintained to the level of the PC at almost all inclusion rates. Additionally at 0.7 kg/t of PY1203, FCR was improved compared to all other treatments. Additionally, bone mineralization was maintained to that of the PC at almost all inclusion rates. This data indicates that the inclusion of high and low specific activity at varying inclusion rates can improve feed conversion and tibia bone mineralization. It can be concluded that birds were able to utilize the phytase enzyme effectively and gain nutritional benefits from it.
Experiment 2 consisted of corn-soybean diets that were supplemented with varying inclusion rates of AC1 (corn expressed glucanase) (0.175 kg/t, 0.35 kg/t, 0.5 kg/t, 0.75 kg/t, 1.00 kg/t, 1.5kg/t, or 2.00 kg/t.). The positive control was comprised of a standard ME diet while the negative control was reduced by 100 kcal/kg from the PC diet. Throughout the 42-day study, all dietary treatments performed similarly when evaluating growth performance (FCR, FC, and BW). When evaluating ileal digestibility, birds that were supplemented with 0.35 kg/t and 0.75 kg/t of AC1, outperformed all other dietary treatments. Additionally, all AC1 supplemented diets-maintained performance to that of the PC and outperformed the NC when AME was evaluated. These findings may suggest that AC1 can improve feed efficiency with a larger energy reduction in diets.
Experiment 3 consisted of a nutrient adequate control, a nutrient reduced negative control and diets supplemented with corn expressed phytase or glucanase. At all inclusions of AC1 and PY1203, FCR was maintained to that of the PC. No differences were seen in body weights however when apparent ileal digestibility was evaluated, birds that were fed a high specific activity corn expressed phytase had an improved AID. At almost all levels of AC1 and PY1203, AME was maintained to that of the PC. This data showed that corn expressed phytase and glucanase maintained broiler performance and compensated for a reduction in avP, Ca, and ME at most levels. | |
