Rumen fermentation pattern and digestion of structural carbohydrates in buffalo (Bubalus bubalis) calves as affected by ciliate protozoa

Four male murrah buffalo calves (average weight 188 kg), each fitted with a rumen and abomasal cannula were subjected to treatments in which they were defaunated (Period I) or refaunated (Period II). The animals were given same wheat straw and concentrate ration in both periods. The pH and concentrations of ammonia nitrogen and total volatile fatty acids were lower concomitant with higher rumen volume and bacterial counts in rumen liquor of defaunated vs. refaunated animals. The molar proportion of propionate increased, and butyrate decreased, with defaunation. Intake of organic matter, neutral detergent fibre, acid detergent fibre, cellulose and hemicellulose did not differ between treatments although their forestomach and whole tract digestibilities were reduced with defaunations. It was concluded that defaunation reduces digestibility of structural carbohydrates in buffalo calves.