Effects of an enzyme cocktail on digestible and metabolizable energy concentrations in barley, corn, and wheat fed to growing pigs

The objective of this study was to determine the effects of an enzyme cocktail (EC), consisting of xylanase, mannanase, and protease, on digestible energy (DE) and metabolizable energy (ME) concentrations in barley, corn, and wheat fed to growing pigs. A pilot study was conducted to determine the effects of EC on the in vitro ileal dry matter digestibility (IVDMD) in 8 sources of feed ingredient including barley, corn, wheat, canola meal, copra meal, cottonseed meal, palm kernel meal, and soybean meal. The IVDMD was determined in each feed ingredients with or without the 0 or 10 g/kg of EC addition. The values for the IVDMD in barley and wheat increased (P<0.05) when the EC was added. However, the EC addition did not affect IVDMD of corn, canola meal, copra meal, cottonseed meal, palm kernel meal, and soybean meal. Based on the pilot study, an animal experiment was conducted to determine the effects of the EC on DE and ME concentrations in barley, corn, and wheat. A 3×2 factorial treatment arrangement with 3 ingredients and 0 or 2 g EC/kg was used. Six barrows with 35.8±3.3 kg body weight were assigned to 6 dietary treatments in a 6×6 Latin square design. There was no interaction between the ingredient and the EC addition, and the effect of the EC addition was not observed. The apparent total tract digestibility of gross energy in diets containing corn was greater (P<0.05) than diets containing barley, but was less (P<0.05) than diets containing wheat. The concentration of DE in barley, corn, and wheat were 3197, 3376, and 3503 kcal/kg (as-fed basis), respectively, and the respective values of ME were 3035, 3304, and 3407 kcal/kg (as-fed basis). In conclusion, the DE and ME concentrations in barley, corn, and wheat were not affected by the EC addition.