Study on some growth characteristics of trout barb (Capoeta trutta) in Bushehr and Tigris basins

Studying growth characteristics of fishes is one of the most important factors in evaluating fish conditions and trout barb is one of the important native fishes in Bushehr and Tigris basin. For this purpose, 223 specimens of trout barb (Capoeta trutta) from four rivers of Bushehr Basin and eigth rivers of Tigris Basin were caught by seine net. The specimens, after collection and anesthetizing in 1% clove oil, were fixed in 10% bufferd formalin and transferred to the Ichthyology Museum of Isfahan University of Technology for further studies. Length and weigth of the specimens were measured by a digital caliper and a digital sclae to the nearest 0.01 mm and 0.01 g, respectively, and length-weight relationship and condition factor were calculated. Based on the parameter b and Pauly test, in general, the growth for this fish was a positive allometric pattern, however, in some populations such as Ahram, Doirej, Eivan Abasi, Sirvan and Zimakan rivers, the growth pattern was negative allometric, indicating unsuitable feeding conditions in these rivers.