| dc.description.abstract | The objective of this research was to determine the effects of a novel xylanase and algal β-glucan (ABG) when included in broiler diets on broiler performance, ileal digestibility of energy (IDE), and immune status. Three experiments were conducted to evaluate the effectiveness of ABG during a challenge and non-challenge setting. In Eexperiment 1, inclusion of ABG at 750 g/MT increased (p<0.05) d 14 average broiler body weights (BW) as compared to the control diet; ABG had no impact on mortality corrected feed conversion ratio (FCR) or relative organ weights. In Experiment 2, inclusion of ABG at 250 g/MT increased (p<0.05) d 10 BW of as compared to the control group prior to Eimeria challenge; inclusion of ABG at 250 and 750 g/MT also increased (p<0.05) BW 7 and 10 d post-challenge as compared to the non-challenged control group. The inclusion of ABG at 250 and 750 g/MT reduced (p<0.05) d 10 FCR as compared to the control group prior to Eimeria challenge. No improvements to performance, intestinal lesion score, or oocyst output were observed with ABG inclusion as compared to the control diet. In experiment 3, inclusion of ABG had no benefit to performance during a Newcastle Disease Virus vaccination program; however, inclusion of ABG at 250 g/MT increased (p<0.05) Newcastle Disease specific antibody titers.
Two experiments were conducted to evaluate the effectiveness of xylanase in diets containing wheat and DDGS at 30 and 15%, respectively, when pelleted at 82 and 92°C, on performance and IDE. In Experiment 1, the inclusion of xylanase at 1000 and 2000 U/kg in diets manufactured at 82°C increased (p<0.05) d 28 BW as compared to the control diet; inclusion of xylanase at all dosage levels reduced (p<0.05) d 38 cumulative FCR as compared to the control diet. Inclusion of xylanase at 250, 500, and 2000 U/kg increased (p<0.05) d 38 IDE as compared to the control diet. In Experiment 2, the inclusion of xylanase in diets pelleted at 92°C had no impact on broiler BW throughout the experiment; however, inclusion of xylanase at all dosage levels reduced (p<0.05) d 21 cumulative FCR. Inclusion of xylanase at doses of 500 U/kg and higher increased (p<0.05) IDE as compared to the control diet.
A final experiment was conducted to evaluate the effectiveness of xylanase in an energy reduced, corn-SBM diet on performance, IDE, digestive tract parameters, and processing parameters. Inclusion of xylanase had no impact on BW throughout the experiment; however, inclusion of xylanase at 250 U/kg in the energy reduced diet reduced (p<0.05) cumulative FCR to levels comparable to the positive control. Inclusion of xylanase at 1000 U/kg reduced (p<0.05) ceca DM content and jejunum viscosity levels as compared to the energy reduced diet; inclusion of xylanase at 2000 U/kg reduced (p<0.05) pancreas weights as compared to other doses of xylanase inclusion. Inclusion of xylanase at 250 U/kg increased (p<0.05) breast meat yield as compared to the negative control at the conclusion of the experiment.
These data confirm the benefits of novel feed additives to improve growth performance and feed efficiency. Inclusion of an algal derived β-glucan improved early broiler performance and immune response as evidenced with improved performance during an Eimeria challenge and increasing Newcastle Disease Virus specific antibody titers. Inclusion of exogenous xylanase increases IDE, resulting in reductions in FCR. | en |
