International Journal of Pure & Applied Bioscience (IJPAB)
Year : 2016, Volume : 4, Issue : 4
First page : (293) Last page : (308)
Article doi: http://dx.doi.org/10.18782/2320-7051.2334
Physico-Chemical Parameters of the Raceways for the Cultivation of Rainbow Trout, Oncorhynchus mykiss (Walbaum), in Kathmandu, Nepal
Rakesh Prasad Bhagat1,2* and Sudip Barat2
1Department of Zoology, Tri-Chandra Multiple Campus, Tribhuvan University, Kathmandu-44600, Nepal
2Aquaculture and Limnology Research Unit, Department of Zoology, University of North Bengal, Siliguri-734 013, District-Darjeeling, West Bengal, India
*Corresponding Author E-mail: rakesh.bhagat2009@gmail.com
Received: 10.07.2016 | Revised: 18.07.2016 | Accepted: 20.07.2016
Abstract
Altogether 18 physico-chemical parameters (5 physical, 9 chemical, 2 climatic, and 2 geographical) of the running water carried from spring-fed torrential stream and flowing in the raceways of Kathmandu, Nepal situated at an altitude of 1550msl were studied to know their suitability for the cultivation of rainbow trout, Oncorhynchus mykiss (Walbaum). Air temperature, in the vicinity of the raceways, ranged from 11.7-26.9 (20.4±1.6oC). Raceway water, throughout the year, was found to be colourless, odourless, and transparent. Water temperature ranged from 8.6-21.5 (16.0±1.4oC), water velocity 1.5-3.0 (2.3±0.14m sec-1), water discharge 37-84 (54.17±3.91L sec-1), turbidity 3-18 (10.1±1.5NTU), pH 6.5-8.1 (7.4±0.17mg L-1), electrical conductivity 35-200 (107.83±16.05µS cm-1), dissolved oxygen 5.9-10.3 (8.3±0.44mg L-1), free carbon dioxide 1.4-4.9 (3.41±0.33mg L-1), total alkalinity 17-96 (55.58±7.39mg L-1), total hardness 11-88 (47.08±7.03mg L-1), phosphate-P 0.01-0.26 (0.13±0.02mg L-1), ammonium-N 0.09-0.91 (0.27 ±0.06mg L-1), nitrate-N 0.01-0.83 (0.2±0.07mg L-1), relative humidity 63.2-88.7 (75.35±2.39%), and rainfall 0.0-402.6 (116.28±41.36mm) in above mentioned altitude and water resource. All the parameters were positively correlated except pH, electrical conductivity, dissolved oxygen, total alkalinity, and total hardness which were negatively correlated with the rest. There was strongest correlation (P>0.01) in between air temperature, water temperature, turbidity, pH, electrical conductivity, dissolved oxygen, free carbon dioxide, total alkalinity, total hardness, and phosphate. Therefore, all the parameters were fluctuated due to the fluctuation in air temperature, water temperature, turbidity, pH, electrical conductivity, dissolved oxygen, free carbon dioxide, total alkalinity, total hardness, and phosphate, thus affecting each other and rest of the parameters. However, water velocity and water discharge, although higher than requirement, were maintained as per need of the cultivation. All the parameters were within permissible limits hence, suitable for rainbow trout cultivation.
Key words: Physico-chemical parameters, raceways, cultivation of rainbow trout.
Full Text : PDF; Journal doi : http://dx.doi.org/10.18782
Cite this article: Bhagat, R.P. and Barat, S., Physico-Chemical Parameters of the Raceways for the Cultivation of Rainbow Trout, Oncorhynchus Mykiss (Walbaum), in Kathmandu, Nepal, Int. J. Pure App. Biosci.4(4): 293-308 (2016). doi: http://dx.doi.org/10.18782/2320-7051.2334
