Rumen's microbial population of dairy cows under different rations

Abstract

Three fistulated Holstein cows were used in "change-over" design comparing three different treatments made with orchad grass pasture plus: A) no/concentrate mixture; B) 3,0 kg/concentrate mixture/cow/day; C) 6,0 kg/concentrate mixture/cow/day. Two separated collections of rumen contents were made in each subperiod of 28 days, to collect the following data, for treatments A, B, or C: liquid rumen volume: turn-overs by 24 hours; total bacterial counts/ml of rumen content; amilolytic bacterial counts/ml of rumen content; total numbers of rumen bacteria; dry matter of rumen content; pH values; and results concerning protozoa, on a relative percentual basis, for: Entodinium sp; Diplodinium sp and Dasytricha sp. For all data there were no statistical differences among the treatments.