RESEARCH CONCERNING SOME FACTORS INFLUENCING THE GROWTH PHYSIOLOGY IN A RAINBOW TROUT POPULATION (Oncorhynchus mykiss), REARED WITHIN CONTROLLED ENVIRONMENT

D. Cocan, Vioara Miresan, R. Constantinescu, I. Bud, Viorica Cosier, Camelia Raducu, Aurelia Pece

Abstract
In this research the authors aim to emphasize the way in which the environmental factors act on the growing rhythm in a rainbow trout (Oncorhynchus mykiss) population, reared within controlled environmental conditions. After the experimental period, the results were compared to those recorded within salmonidae classical rearing system - Trout Fiad Fishery, county of Bistrita - Nasaud. In experimental development, 100 individuals were randomly selected from the experimental system and 100 from Fiad trout fishery, and measured monthly. According to the presented data, for the described experimental system, superior results of the growing rhythm of the body weight and total length were recorded compared to the results recorded within classical system of salmonidae rearing - Fiad trout fishery. This can be explained by the influence of the temperature factor, because pH and dissolved oxygen frame within normal values in both rearing systems.

Key words: rainbow trout, growth physiology, environmental factors, rearing systems