Food passage time through the alimentary tract of a brazilian teleost fish, Prochilodus scrofa (Steindachner, 1881) using radiography

Abstract

Food passage time through the digestive tract of a detritivorous freshwater fish (Prochilodus scrofa) was determinate by radiographic techniques using barium sulfate as a contrast medium. The fish were kept in tanks at a constant temperature of 23.5ºC and received by an oral catheter a mixture of 2.5 parts of ground ration and 1 part of oral suspension of contrast medium (Celobar). Radiographs were taken at intervals of 3 hours. Immediately after the introduction of the mixture the stomach was outlined by the contrast. A sphincter was observed between the cardiac and the muscular stomachs. After 3 hours, 80 per cent of the proximal intestine was filled. After 6 hours the contrast reached the proximal, medial and distal portions of the intestine. After 9 hours 70 per cent of the distal intestine was filled and after 12 hours, the rectum segment was still marked (25 per cent of the distal portion of the intestine).