Abstract
Objective—To evaluate effects of IV administration of penicillin G potassium (KPEN) or potassium chloride (KCl) on defecation and myoelectric activity of the cecum and pelvic flexure of horses.
Animals—5 healthy horses.
Procedure—Horses with 12 bipolar electrodes on the cecum and pelvic flexure received KPEN or KCl solution by IV bolus 4 hours apart. Each horse received the following: 2 × 107 U of KPEN (high-dose KPEN) followed by 34 mEq of KCl (high-dose KCl), 1 × 107 U of KPEN (low-dose KPEN) followed by 17 mEq of KCl (low-dose KCl), high-dose KCl followed by high-dose KPEN, and low-dose KCl followed by low-dose KPEN. Number of defecations and myoelectric activity were recorded for 60 minutes. The first three 5-minute segments and first four 15-minute segments of myoelectric activity were analyzed.
Results—Number of defecations during the first 15- minute segment was greater after high-dose KPEN treatment than after high-dose or low-dose KCl treatment. Compared with reference indexes, myoelectric activity was greater in the pelvic flexure for the first 5- minute segment after high-dose KCl treatment, in the cecum and pelvic flexure for the first 5-minute segment and in the pelvic flexure for the first 15-minute segment after low-dose KPEN treatment, and in the pelvic flexure for the first and second 5-minute segments and the first three 15-minute segments after high-dose KPEN treatment.
Conclusions and Clinical Relevance—IV administration of KPEN stimulates defecation and myoelectric activity of the cecum and pelvic flexure in horses. Effects of KPEN may be beneficial during episodes of ileus. (Am J Vet Res 2003;64:1360–1363)