Questions and Answers Regarding Rumenocentesis and the Diagnosis of Herd-Based Subacute Rumen Acidosis

Abstract

Subacute rumen acidosis is a common and serious health and production problem in the dairy industry. The absence of a reliable diagnostic system is probably responsible in part for the current number of problem herds. Ration formulation guidelines for fiber and nonstructural carbohydrates (NSC) are helpful, but by themselves are not adequate for the diagnosis or prevention of subacute rumen acidosis. Measurement of rumen pH is a useful ancillary test in the diagnosis of subacute acidosis. Rumenocentesis is the most practical field method of collecting a rumen fluid sample free of saliva contamination.¹² An approach to problem herds has been developed where rumen pH is measured in two groups of cows: periparturient cows that have been exposed to the lactation rations for 1 to 20 days, and adapted lactating cows from 45 to 150 days in milk.¹³ The approach has attracted great interest and questions from veterinarians, nutritionists, and dairy herd managers throughout North America and Europe in the past year. In a question and answer format, this paper will present the most frequent concerns and issues that have been raised by these groups.