Livestock Internal Medicine Resident UC Davis Large Animal Hospital - VMTH Davis, California
Literature describing rumen juice (RJ) analysis as a diagnostic tool is based on analysis of a 10mL sample directly after sampling. However, it may be challenging to obtain 10mL of RJ from some patients, and clinical circumstances may delay the RJ analysis.
This study quantified the effect of sample volumes, 2, 5, 10, 50 and 100mL; and time-to-analysis on RJ analysis after 30 and 60 minutes (min).
Two liters of RJ were obtained from a cannulated donor cow 21 times. The samples were subdivided into 1 set per time point. A set was composed of 2 duplicates of each sample volume. Samples were analyzed at 0, 30, and 60 min after sampling. Analysis of RJ consisted of pH, methylene blue reduction time (MBRT), and protozoal motility scoring.
At 30 and 60min, pH of the 2mL and 5mL samples were significantly (p < 0.05) higher than pH of the 10mL, 50mL, 100mL samples. The MBRT was significantly prolonged for 2mL samples compared to 10, 50 and 100mL samples at all time points. The pH and MBRT at 60min were significantly higher than at 0min for all sample volumes. There was no significant difference in protozoal motility for all sample volumes at all times.
This study indicates that the interpretation of RJ analysis may be altered by sample volumes less than 10mL or 30 to 60min delays in analysis.