Influence of dietary protein and lipid levels on growth, body composition and utilization efficiencies of Arctic charr, Salvelinus alpinus L.

• Published in: Journal of Fish Biology
• Main Author: Tabachek, J. L.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 1986
• Subjects: Arctic; Arctic charr; Salvelinus alpinus
• Online Access: http://dx.doi.org/10.1111/j.1095-8649.1986.tb04933.x; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fj.1095-8649.1986.tb04933.x; https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1095-8649.1986.tb04933.x

Growth, body composition and feed utilization were evaluated for Arctic charr fed a control diet and nine practical diets formulated to contain three protein levels (34, 44 or 54%) at each of three lipid levels (10, 15 or 20%). Fish were raised for 24 weeks at 12° C. Increasing either dietary protein and/or lipid resulted in improved weight gain, feed efficiency and energy retained. Protein efficiency ratio and protein retained were directly related to dietary lipid and inversely related to dietary protein. A sparing effect of lipid on protein was evident where, at each protein level, Arctic charr utilized protein more efficiently with each increase in dietary lipid. Levels of 34% protein and/or 10% lipid were well below the requirements for Arctic charr (initial weight, 4.6 g). Within the range tested, the dietary combination of 54% protein with 20% lipid maximized weight gain and feed efficiency and resulted in fish with low liver and body lipid contents. However, if lowest feed cost per kg gain is an important factor, the 44% protein—20% lipid diet would be less expensive to use, although it results in a minor reduction in growth potential.