Experimental diets and excreta samples were analyzed in triplicate for dry matter (DM, method 930.15;
[16 ]), crude protein (CP, method 990.03;
[16 ]), ash (method 942.05;
[16 ]), calcium, and phosphorus (method 985.01;
[16 ]). Gross energy was measured by a bomb calorimeter (Model 1261, Parr Instrument Co., Moline, IL), and chromium concentrations of experimental diets and excreta samples were determined with an automated spectrophotometer (Jasco V-650, Jasco Corp., Tokyo, Japan) according to the procedure of Fenton and Fenton
[17 (link)]. The ATTD (%) of nutrients was calculated by the following formula:
Where
Nf = nutrient concentration in feces (%)
Nd = nutrient concentration in diet (%)
Cf = chromium concentration in feces (%)
Cd = chromium concentration in diet (%)
The microbiological assay of excreta was carried out by the procedure suggested by Choi et al.
[18 (link)]. The microbial groups enumerated were total anaerobic bacteria (TAB; plate count agar, Difco Laboratories, Detroit, MI, USA), Bifidobacterium spp. (MRS agar), coliforms (violet red bile agar, Difco Laboratories, Detroit, MI, USA), and Clostridium spp. (Tryptose sulphite cycloserine agar, Oxoid, Hampshire, UK). The anaerobic conditions during the TAB and Clostridium spp. assays were created by using the gas-pak anaerobic system (BBL, No. 260678, Difco, Detroit, MI, USA).
[16 ]), crude protein (CP, method 990.03;
[16 ]), ash (method 942.05;
[16 ]), calcium, and phosphorus (method 985.01;
[16 ]). Gross energy was measured by a bomb calorimeter (Model 1261, Parr Instrument Co., Moline, IL), and chromium concentrations of experimental diets and excreta samples were determined with an automated spectrophotometer (Jasco V-650, Jasco Corp., Tokyo, Japan) according to the procedure of Fenton and Fenton
[17 (link)]. The ATTD (%) of nutrients was calculated by the following formula:
Where
Nf = nutrient concentration in feces (%)
Nd = nutrient concentration in diet (%)
Cf = chromium concentration in feces (%)
Cd = chromium concentration in diet (%)
The microbiological assay of excreta was carried out by the procedure suggested by Choi et al.
[18 (link)]. The microbial groups enumerated were total anaerobic bacteria (TAB; plate count agar, Difco Laboratories, Detroit, MI, USA), Bifidobacterium spp. (MRS agar), coliforms (violet red bile agar, Difco Laboratories, Detroit, MI, USA), and Clostridium spp. (Tryptose sulphite cycloserine agar, Oxoid, Hampshire, UK). The anaerobic conditions during the TAB and Clostridium spp. assays were created by using the gas-pak anaerobic system (BBL, No. 260678, Difco, Detroit, MI, USA).