Changes with Age in Glutamic Oxalacetic Transaminase Activity of Sonically Oscillated Rumen Juice Compared to Total Steam Volatile Fatty Acids in Calves Fed Different Roughages
A preliminary experiment showed that the concentration of GOT activity was highest in the sonically oscillated protozoal fraction, next highest in the oscillated bacterial fraction and lowest in the cell free fraction of fresh rumen juice from a steer fed a ration of alfalfa hay. In this experiment the changes in GOT activity of sonically oscillated fresh rumen juice was measured bi-weekly in calves fed different roughages (alfalfa, soybran flakes and beet pulp) 16 wk of age and compared with steam volatile fatty acids in the same rumen juice samples. Since most of the GOT activity in the rumen juice was released from within the cells of microorganisms by the sonic oscillation, it was reasoned that the observed differences due to ration and to age were largely reflections of gross differences in numbers and kinds of rumen microorganisms. Changes in GOT may reflect more closely than SVFA the over-all changes in rumen microbial development.