5-Year Impact Factor: 1.4
CiteScore: 3.1
Evaluation of Commercial Trout Feeds: Feed Consumption, Growth, Feed Conversion, Carcass Composition and Bio-economic Analysis
2 Kaşüstü Primary School, Yomra, Trabzon, Turkey Viewed : 4777 - Downloaded : 9041 Feed consumption (FC), growth, condition factor (CF), feed conversion (FCR), tissue composition and the bioeconomics of production were examined in juvenile rainbow trout (Oncorhynchus mykiss) fed three commercial steam pelleted feeds over 22 weeks. Fish were held in six 300 l fiberglass tanks with two replicates of 50 fish (initial weight ca.16.5 g and CF ca. 1.24) per treatment. The trial was run at ambient temperature (10.8-23.3ºC) under natural summer-autumn photoperiod (40º55'N 40º12'E) and the fish were fed to apparent satiation twice per day.
All feeds exhibited characteristics of a typical “standard” trout grower and among the main nutrient components only protein contents slightly differed from manufacturer’s declarations. Mean weights of the fish at the end of the trial were 383.6, 359.6 and 366.9 g, the final weight of the fish given feed A being significantly higher than those given feeds B and C (P<0.05). CF increased during the course of trial and was ca 1.6 at termination with small differences among groups. Mean daily feed consumption varied from 1.1 to 4.4% of body weight (bw), but overall means of the groups showed slight variations, 2.11-2.22% of bw. FCR and the protein efficiency ratios (PER) were within the ranges 1.04-1.12 and 2.03-2.08 and did not differ significantly among groups. Feed did not influence on dressing percentage, but it seemed to affect on lipid content of the tissue. Feed cost of kg weight gain was highest for feed C, while it was similar for other two feeds.
Keywords : Rainbow trout, Oncorhynchus mykiss, feeding, feed consumption, growth, feed conversion, tissue composition, bio-economic analysis