The objective of this study was to determine the transit time of two diets in the digestive tract of the Amazonian manatee in captivity. We tested separately two different diets: one composed exclusively of grass of the genus Brachiaria (experimental diet - ED- A 1) and the other composed of grass Brachiaria added with small portions of extruded pellets for horses (experimental diet ED- A 2). Two healthy adult manatees were selected and isolated from the rest and underwent a period of food acclimation with the experimental diets for 15 days. After this period, the experimental diet was marked with a plastic colored tape of 10-cm length and given to the animals. The manatees were monitored at intervals of 1 hour and all fecal material was collected until recovery of the markers. The mean transit time of ED - A1 was 123h57min , about 5.16 days and ED - A 2 was 125h04min or 5.21 days. There was no statistical difference (P <0.05) between the transit time of the two diets provided. The transit time observed (approximately 5 days) has also been reported by other authors for this species and is considered a strategy to increase the absorption time of food nutrients. Despite the small sample size, the results suggest that the use of pellets in the diet of the Amazonian manatee did not affect the transit time of the grass. Therefore, it is reasonable to believe that the introduction of concentrated food (pellets) does not affect the efficiency of the animal to digest and absorb food properly.
nutrition; monogastric; aquatic mammal
