Research Article

Algal and Vegetable Oils as Sustainable Fish Oil Substitutes in Rainbow Trout Diets: An Approach to Reduce Contaminant Exposure

Table 1

Feed components and chemical composition of experimental diets (g/kg dry matter).

18 FO18 SO18 CO18 COS25 FO25 SO25 CO25 COS

Ingredient composition
Fish oil, herring21.32.72.72.813.50.00.00.0
Soybean oil0.018.60.00.00.013.50.00.0
Canola oil0.00.018.615.00.00.013.510.5
Schizochytrium sp.0.00.00.09.00.00.00.06.5
Herring meal22.022.022.022.032.532.532.532.5
Blood cell meal
AP3017.07.07.07.010.010.010.010.0
Corn gluten meal21.021.021.020.034.034.034.033.0
Wheat middlings13.013.013.010.54.04.04.02.3
Whey11.411.411.49.52.82.82.82.0
Sipernat™1.01.01.01.01.01.01.01.0
CaHPO40.50.50.50.50.50.50.50.5
Lysine0.20.20.20.20.20.20.20.2
Vitamin/mineral premix10.60.60.60.60.60.60.60.6
Carophyll pink premix0.30.30.30.30.30.30.30.3
Chemical composition
Dry matter (g/kg)92.092.091.292.892.593.192.692.0
Crude protein45.244.645.446.461.661.762.161.7
Total lipid21.621.421.222.515.315.415.916.2
Ash7.57.57.78.18.58.48.48.9
Gross energy (MJ/kg DM)24.424.324.424.524.123.924.124.0
Calculated P/E ratio (g DM/MJ)218.518.318.618.925.525.825.825.7

18 FO, 18 DP/DE diet with 100% fish oil; 18 SO, 18 DP/DE diet with 75% soybean oil; 18 CO, 18 DP/DE diet with 75% canola oil; 18 COS, 18 DP/DE diet with 75% blend of canola oil and Schizochytrium sp.; 25 FO, 25 DP/DE diet with 100% fish oil; 25 SO, 24 DP/DE diet with 75% soybean oil; 25 CO, 25 DP/DE diet with 75% canola oil; 25 COS, 25 DP/DE diet with 75% blend of canola oil and Schizochytrium sp.; DM, dry matter; DP/DE, digestible protein/digestible energy (lipids). Canola oil, soybean oil, and Schizochytrium sp algae were devoid of PCBs, pesticides, toxaphenes, and flame retardants. Herring meal was found to contain the following: PCBs: 6.5 ppb; pesticides: 2.45 ppb; toxaphenes: 0.41 ppb; flame retardants: 0 ppb. Herring oil was found to contain the following: PCBs: 386 ppb; pesticides: 147 ppb; toxaphenes: 46.8 ppb; flame retardants: 49.9 ppb. 1Salmonid vitamin/trace mineral premix from Corey (Fredericton, NB). 2P/E ratio = protein/energy ratio; calculation based on crude protein and gross energy values determined for the experimental diets.