Intra-oral food manipulation of carp and other cyprinids: adaptations and limitations.

The heterogeneity of the cyprinid fishes (about 2000 species) and their feeding requires a general model of aquatic feeding. In this model the timing of mouth and gill slit opening and the relative contribution of head expansion and swimming are determining factors. The following elements have been distinguished in the feeding process of cyprinid fishes: search/choice, intake (particulate intake and gulping), size-and taste selection, intra-oral transport (including repositioning), mastication and deglutition. The recognition of these processes is based on the combined use of X-ray, cine film, video and emg techniques. Structural specialisations, including the intra-oral density of sensory elements and their central connections with associated feed back loops, enable a wide variety of combinations and regulation of (stereotyped) motor patterns.