The aim of the study was to describe location, sonographic characteristics and measures of the stomach and small intestine of equines at different ages. Abdominal ultrasonography was performed on 88 healthy equines of either sex, aged 1, 7 and 15 days, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 and 11 months and 1, 3 and 5 years, with 20 animals per group. Location, characteristics and measurements of stomach, duodenum and jejunum were evaluated. Descriptive statistics were performed for each measurement and the percentile for each age was analyzed. The work showed the growth and characteristics of the organs evaluated over time. Adult animals showed a minimum of 4 duodenal movements per minute. It was possible to locate the organs evaluated in all animals. The detailed ultrasound examination of these organs allowed gathering information that could be used to assist in the care of future patients.