Right-side torsion of the abomasum in dairy cows: classification of severity and evaluation of outcome.

A retrospective analysis was made of 100 cases of surgically corrected right-side torsion of the abomasum (RTA) in dairy cows. A classification for degrees of severity of RTA was developed, based on the amount of fluid sequestered in the abomasum. Serum concentrations of Na+, K+, AND Cl- decreased with increasing severity of RTA. Cows in the most severely affected classification were markedly hypochloremic and hypokalemic. The PCV, plasma protein concentration, and pulse rate increased with increasing severity of RTA. Statistically significant correlations were observed between postsurgical outcome and classifications of RTA, serum Cl- concentration, and pulse rate. The outcome was not statistically related to serum concentrations of Na+ or K+, PCV, or plasma protein concentration.