THEORETICAL ESTIMATION OF RUMEN OUTFLOW RATE FROM TIME-COURSE RUMEN FERMENTATION OBSERVATIONS

The nylon bag technique for studying the rumen degradation of feeds is widely used. The time-course rumen fermentation observations are util ized for determining the degradation constant and the effective degrad ability (ED) at any rumen outflow rate. The ED values for the average rumen outflow rate of 0.05 h(-1) by two models, assuming complete degr adation of material or taking into consideration only the potentially degradable fraction, were found to differ by two percentage units only , inspite of wide variation. in the degradation constants. This small difference is explained on the difference between the assumed and the actual rumen outflow rate under the experimental conditions. The rumen outflow rate for the least difference in the ED values by the two mod els may be utilized for the theoretical estimation of the actual rumen outflow rate.