Growth Particularities of Rainbow Trout (Oncorhynchus mykiss) in Fishery Bistrişorii Valley, Alba County, Romania Andrada IHUT, Vioara MIREŞAN, Camelia RĂDUCU, Daniel COCAN, Radu CONSTANTINESCU University of Agricultural Sciences and Veterinary Medicine, Faculty of Animal Science and Biotechnologies, 3-5 Mănăştur Street, 400372 Cluj-Napoca, Romania; vmiresan@yahoo.com Bulletin UASVM Animal Science and Biotechnologies 71(1) / 2014, 9-13 Print ISSN 1843-5262; Electronic ISSN 1843-536X Abstract In this paper the authors showing the way in which the environmental factors act on the growing rhythm at in a population of rainbow trout (Oncorhynchus mykiss), reared within classical rearing system. The biological material was represented by embryonated roes taken from Brade Trandafir fishery Remeti, Bihor County, Romania, which have been studied since larva stage (0.07±0.001g) till the delivery weight (266.70±0.544g), for 480 days, in which there were monitored medial parameters of water and growth indices. Hydrological characteristics of the Bistrişorii Valley had been framed with the water temperature between a minimum of 4.6 o C in December and a maximum of 17.5 o C in July of the year 2011, but in the next year (2012) were obtained a minimum of 3.9 o C in January and a maximum of 21.7 o C in July. Growth indices (TG and DWG) presented the following values: TG=266.63g; DWG=0.573g. To obtain a high quality meat and economic efficiency it is necessary to establish a proper strategy for planning fish production, taking into account the influence of environmental, nutritional and genetic factors. Keywords rainbow trout, market demand INTRODUCTION Fish meat production capacity depends on the species considered its own, by the quantity and quality of feed given, by the environmental conditions and the rearing technology. The productive capacity and the economic efficiency, also depend on the anatomical and morphological characteristics of the species and some physiological features and meat microstructure. Rainbow trout (Oncorhynchus mykiss) is found in the most trout farms from Romania, due to its adaptability at intensive farming conditions. The literature deals extensively aspects about meat quality of rainbow trout and the slaughter yields, depending on several factors such as feeding structure (Karabulut et al., 2010), season, body size (Bugeon et al., 2008; Bureau et al., 2000; Mihalca, 2011) or fish age (Bud et al., 2008). MATERIALS AND METHODS The study lasted 480 days, from March 2011 until July 2012 in the fishery Bistrişorii Valley, from Alba County, Romania. This has an area of 250 m 2 and is situated at an altitude of 630 m and the need for water is provided from the Bistrişorii Valley with flow rate of 40 liters/sec. The biological studied material was represented by embryonated roes of rainbow trout (Oncorhynchus mykiss), taken from Brade Trandafir fishery Remeti, Bihor County, Romania. Eggs were put in Wacek Universal Hatchery type and providing an average water temperature of 9 o C the larvae have hatched over an incubation period of 30±2 days. Somatic measurements were performed monthly and in every step of this study were weighed 100 fishes, randomized retained from growth pools and after that they were released. During the study we brought to you by CORE View metadata, citation and similar papers at core.ac.uk