The objective of this study was to investigate the effect of senna associated with intravenous fluid therapy (SEN), isotonic polionic enteral solution (PE) and intravenous fluid therapy (IV) alone in the treatment of experimental large colon impaction in horses. Fifteen horses with experimentally induced colon impaction were divided in three groups: Group PE received the isotonic polionic enteral solution (8 mL kg-1 h-1,during 48 h); Group SEN received senna (20 mg kg-1, two doses with 24 h interval) + Ringer lactate i.v. (10 mL kg-1 h-1 12 h-1, for two days); and Group IV received Ringer lactate i.v. (16 mL kg-1 h-1 12 h-1, for two days). The treatment protocol of group PE increased fecal hydration and helped remove impaction faster; however, prolonged intestinal hypomotility were observed. The treatment protocol SEN normalized the intestinal motility faster; however the time required to remove impaction was higher and caused higher increase in abdominal distention and pain, as well as less capacity to revert dehydration. The treatment used for group IV removed the impaction, similarly to PE, and stimulated intestinal motility faster; however, it was the treatment that promoted less fecal hydration. The results showed that the treatments used in groups PE and IV were more efficient for the treatment of induced colon impaction in horses. The group SEN was also efficient, but showed the most important adverse effects.
horse; colic; large colon; fluid therapy; laxatives
