Intestinal disaccharidase activity in a monotreme and eight species of marsupials (with an added note on the disaccharidases of five species of sea birds)

Abstract

1. 1. The monotreme ( Tachyglossus aculeatus) had levels of activity of maltase, isomaltase and trehalase which were similar to those found in man and other placental mammals. By contrast, trace levels only of lactase and cellobiase were found. Sucrase was completely absent., 2. 2. Most marsupials had all the above disaccharidase activities and at similar levels to those found in the placental mammals. Notable exceptions were the absence of sucrase in the kangroo ( Macropus giganteus) and in the short-nosed bandicoot ( Isoodon obeselus) and the extremely low trehalase activity in the koala ( Phascolarctos). 3. 3. Similarities in presence and development of disaccharidases in the kangaroo, which has a ruminant-like digestive system, and the placental ruminants were noted. 4. 4. Maltase, sucrase and lactase activities in five species of sea bird were found to be very low by comparison with most mammals.