A Retrospective Survey of Equine Acute Abdomen in a Breeding Region of Japan based on Agricultural Mutual Relief Insurance Data

Abstract

We summarized the data from a mutual relief livestock insurance program, an insurance system applied under the Law of Compensation for Agricultural Damage, to determine the incidence of equine acute abdomen in the Hidaka district, a major horse-breeding region of Japan. A retrospective survey was conducted over a three year period, from January 2001 to December 2003. During this time, the number of cases of acute abdomen was 8,481 out of a total of 53,756 cases of diagnosed diseases (15.8%). During the same period, the number of cases of death due to acute abdomen was 306 out of a total of 1,106 deaths (27.7%). When a provisional population was calculated from the number of horses insured in November 2002 (45,624), the annual rates of "disease or injury" and "death or disuse" due to acute abdomen were 18.6% and 0.7%, respectively for the three year period. The most common forms of acute abdomen were intestinal tympany and constipational colic (5,455 cases, 64.3% of all acute abdomen cases); and volvulus was the most frequent cause of death (108 cases, 35.3% of the number of deaths due to acute abdomen). The incidence of intestinal obstruction, intestinal narrowing, intussusception and volvulus was highest from May to August (79 cases, 53.4% of a total of 179 cases). The mortality rate of acute abdomen was highest in those horses older than 21, followed by the range in age from 16 to 20. The removal of the factors associated with acute abdomen which are indicated in this report may be useful for prevention of acute abdomen.