Evaluation and validation of a paralumbar fossa transabdominal rumen fluid sampling technique

Abstract

A simple method to obtain rumen fluid via the left paralumbar fossa was evaluated on 58 adult cattle. Using a 16-gauge 1.5 inch (3.8 cm) needle, rumen fluid was successfully collected and evaluated from 45 of 58 head (78%). The primary reason for failure was body wall thickness exceeding the 1.5 inch (3.8 cm) needle (P = 0.0002). Average rumen pH of the 45 cattle samples was 7.9; the test cattle were primarily fed guinea grass with occasional brewer's grain supplement. An average 3 protozoa per field under 40 x magnification were seen. No external hematomas or other swellings were seen during the 3-week follow-up observations, and no complications were noted. Eleven of the 58 cattle (19%) had increased body wall thickness, based on ultrasonographic follow-up. The average length of time required to obtain a rumen sample, measured by introduction of the needle to the withdrawal of the needle, was 3 seconds (range< 1 to 8 sec). We conclude that the left paralumbar fossa trans-abdominal rumen fluid sampling technique is a safe and efficient method to obtain rumen fluid in cattle with a moderately thin (~ 30 mm) body wall.