Determination of gastrointestinal transit time in Podocnemis expansa Schweigger, 1812 (Amazon turtle) (Testudines: Podocnemididae)

Abstract

The Amazon turtle is herbivorous but can feed on a small amount of food of animal origin. The speed of digestion of these animals is influenced by temperature and diet. Studies on the transit in the gastrointestinal tract are necessary in order to understand the food digestion process in the animal’s organism. We therefore sought to establish the gastrointestinal transit time of this reptile, which is information widely used in the clinical care of wild animals. The study involved 10 animals from the Nova Crixás – GO breeding farm, weighing an average of 2.595 ± 3.22 Kg. The animals were fed orally with a barium sulfate suspension (10ml/Kg of Bariogel^® mixed with mineral oil (Nujol^®), in a proportion of 70% barium sulfate to 30% oil. The animals were then radiographed in the dorsiventral position, with the X-ray machine set at 80 kV, 250 mA and 0.74” of exposure, at preestablished intervals of time the contrast remained in the organism. Five minutes after administration of the contrast fluid, the stomach was filled, while the jejunum and ilium were filled between 6 and 24 hours, the cecum between 24 and 96 hours, and the colon and rectum between 24 hours and the 5^th day. Complete emptying of the stomach occurred between the 5^th and 24^th day. Elimination of the contrast material from the duodenum occurred from the 7^th to the 15^th day, and from the jejunum-ilium between the 7^th and 17^th day. The cecum expelled the contrast fluid from the 12^th to the 29^th day, with complete discharge occurring between the 15^th and 29^th day, Therefore, the total gastrointestinal transit time in P. expansa was, on average, 22.5 days, with a minimum of 15 days and maximum of 29 days.