Effect of starvation on morphometric changes in Rhynchocypris oxycephalus (Sauvage and Dabry)

A 75-day study was conducted to determine the effect of starvation on classical and truss parameters in Rhynchocypris oxycephalus (Sauvage and Dabry). Truss dimensions of almost the entire head and trunk region as well as the abdomen were increased significantly through feeding or starvation (P < 0.05). Truss dimensions of the caudal region generally decreased through feeding or starvation. particularly, those dimensions at the hind part of the trunk. There were some significant decreases in classical dimensions of the head region during feeding, in relation to body depth characteristics in the trunk and caudal region during starvation, whereas there was only one decreasing classical dimension in the caudal region during feeding. The results of this study indicate that application of the truss network as a character set enforces classical coverage across the body form, discrimination among experimental groups thus being enhanced. Considering that the dimension of the lower part of the head and some truss and classical dimensions were least affected by feeding and starvation, these dimensions may then be useful as a taxonomical indicator to discriminate the species of Rhynchocypris sp. The value of trunk region dimensions with a large component of body depth in R. oxycephalus is most likely to be compromised by variability related to differences in feeding regimes of fish in different habitats.