Effects of optimal carbohydrases cocktails screened using an in vitro method on nutrient and energy digestibility of different fiber source diets fed to growing pigs

This study aimed to determine the effects of optimal carbohydrases cocktails (OCC) screened using an in vitro method on nutrient and energy digestibility of corn-soybean meal-based diet (CSM), corn-soybean meal-corn distillers dried grains with soluble-based diet (CSMD), and corn-soybean meal-miscellaneous meal-based diet (CSMM) in growing pigs. One of 6 test diets (3 basal diets and 3 basal diets with corresponding OCC) was allotted to 3 of 18 ileal-cannulated barrows according to a triplicate 6 × 3 incomplete Latin Square design with 6 treatments and 3 periods. Ileal digesta and feces were collected to measure the coefficient of apparent digestibility of nutrients at distal ileum (CAID) and total tract (CATTD) of pigs. The OCC addition increased the CAID of dry matter (DM) and ash in CSM diet (P < 0.05). The CAID of neutral detergent fiber (NDF) and acid detergent fiber (ADF) in CSMD diet were improved by the inclusion of OCC (P < 0.05), whereas the CAID of DM, crude protein (CP), ash, and gross energy (GE) were decreased by the OCC addition (P < 0.05). The OCC addition increased the CAID of macronutrients and energy and the CATTD of DM, CP, ether extract, ash, carbohydrate (CHO), and GE in CSMM diet (P < 0.05). The OCC inclusion improved the CAID and the coefficient of standardized ileal digestibility (CSID) of Asp and Cys (P < 0.01) in CSM diet but decreased the CAID and CSID of Ala (P < 0.05). The CAID and CSID of Ile, Leu, and Cys in CSMD diet were decreased by the OCC addition (P < 0.05). All most all amino acid (AA) digestibility in CSMM diet were improved by the OCC addition (P < 0.05) except the CAID and CSID of Cys, Glu, and Tyr. In conclusion, the effects of OCC on the nutrient and energy digestibility for pigs fed different fiber source diets are inconsistent, and the OCC addition could improve the ileal and total tract nutrient and energy digestion in CSMM diet.