Effect of expander-extruder processing on nutritive value of maize cobs based complete diet of buffaloes

Expander-extruder processed maize cobs (40%) based complete diet, correspon ding mash diet and a conventional diet (containing concentrate mixture and ground-maize cobs in 60: 40 ratio as in complete diets i e as such basis) w ere fed to 3 permanently fistulated male buffaloes using 3x3 latin square d esign to assess the effect of these diets on rumen fermentation pattern and nutrient utilization. The DMI and water intake/kg DMI were comparable on a ll the diets. Total N, TCA-precipitable N and residual N were increased (P< 0.01) from conventional diet to mash and expander-extruder processed diet w here the trend in NH3-N concentration was reverse. All the N fractions exce pt NH3-N and TVFA concentrations peaked at 4- hr post feeding. The digestib ilities of DM, OM and CP were significantly (P<0.05) higher on expander-ext ruder processed diet compared to other 2 diets. All the animals were on pos itive N, Ca and P balances under 3 treatments. Expander-extruder processing increased the DCP and TDN contents of diet and the intakes on all the diet s were much higher than the recommended level for maintenance of adult buff aloes. The results indicated that the rumen fermentation pattern in buffalo es was normal on maize-cobs based diets and that expander-extruder processi ng stimulated to some extent the rumen fermentation pattern and enhanced th e nutrient utilization of complete diet.