Morphological characterization of the alimentary tract of Antarctic fishes and its relation to feeding habits
Morphological and morphometric characteristics of the alimentary tract in 22 species of carnivorous antarctic fishes were studied. It is shown that all of these species have similar, well-developed Y-shaped stomachs with generally thick (0.5–1.0 mm) walls. The relative stomach lengths are also similar, ranging from 9.8 to 22.2% of body length. Relative intestine lengths, a characteristic frequently used as an indicator of the kind of food eaten by a species, are also remarkably similar among most species (31 to 67%). Notothenia gibberifrons, a conspicuous benthos feeder, has a significantly longer intestine (91%), probably as an adaptation to the quantity of undigestible material (mud) incorporated with its faunal prey. These values fit within or below the limits (60–150$) of relative intestine length described in the literature for carnivorous fishes. The number of pyloric caecae is in general relatively low and fairly constant in each species. It is concluded that the morphological features studied could represent similar adaptations of these antarctic fishes to a similar carnivorous diet.
- 1 - sciences appliquees, technologies et medecines
- 2 - sciences biologiques et medicales
- 3 - sciences biologiques fondamentales et appliquees. psychologie
- 4 - vertebres: systeme cardiovasculaire
- 1 - Life Sciences ; 2 - Agricultural and Biological Sciences ; 3 - General Agricultural and Biological Sciences