Gastrointestinal transit and digestive rhythm in Biomphalaria glabrata (Say)

Transit of X-ray opaque Micropaque(TM) particles in the digestive tract of Biomphalaria glabrata nta was investigated by X-radiography. Passage throug h the whole animal lasted up to 200 min depending on the experimental condi tions (starvation fed ad libitum etc.). For the first time, cyclic activity of the digestive gland could be visualised: the gland is emptied every 60- 110 min discharging undigested particles. In the afternoon transport of pro bably predigested material from more distally located parts of the digestiv e tract into the esophagus can be observed indicating resorption processes occurring in the esophagus.