What should the rumen pH be on a rumenocentesis sample?
The normal rumen pH is usually above 5.8. The range of 5.6 to 5.8 might be considered marginal. Readings at or below 5.5 are considered to be abnormal. It is suggested that 10-12 cows should be tested. With a TMR ration, testing should be done 5-8 hours after feeding. If greater than 30% of the readings taken are below 5.5, it should be considered abnormal on a herd basis.
