In the current international milk payment system, where the quality is the main factor; two fundamental aspects have acquired great importance: the somatic cells count and the amount of total solids. The first one depends on the health of the mammary gland and the second factor, which has more economic impact for the dairy industry, is directly related to feeding management and the cattle breed. The environment of the rumen can modify the composition of the milk, specially the fat percentage. The main source of protein in the ruminants depends on the synthesis of protein in the rumen. The current feeding systems used in high-yielding dairy cows, predispose them to the outcome of metabolic syndromes that directly or indirectly affect the milk production. The purpose of this study was to establish a relation between the index of the rumen environment (Methylene blue reduction time and pH) and urinary pH with the composition of the milk and the somatic cells count. None statistical relation was found among the parameters evaluated. The average values of non fat solids in this study were below the official values approved in Brazil.
rumen; ruminal pH; total solids; milk composition