Effect of algal incorporation on growth, survival and carcass composition of rainbow trout (Oncorhynchus mykiss) fry.
A nutritional assay has been conducted with rainbow trout fry (Oncorhynchus mykiss) using a biomass of photosynthetic micro-organisms. The algal biomass was incorporated in the feed at increasing levels (12.5%, 25% and 50%) in order to verify the effects on survival (%), growth (length and mass) and carcass quality of the fish (skin color, water, protein and lipid content). Two commercial feeds (CF, as sold, and 0% A, reprocessed without algae) have been used as controls. After eight weeks at 10 degrees C, the growth has been significantly reduced in fish fed the feeds containing 25% and 50% algae diets (P<0.01). Moreover, an incorporation of algae higher than 12.5% in the feed led to a increase of water content (CF versus other diets; P<0.01) and TL (CF versus 50% A; P<0.01) (wet basis) content of carcasses. Survival was 100% in all treatment groups. Under the experimental conditions used, the results obtained show that a maximum of 12.5% of algal biomass can be incorporated in the feed for rainbow trout fry (O. mykiss) without negative consequences on growth and body content in lipids and energy of fish.
Dallaire
V
V
Département des sciences animales, Pavillon Comtois, Université Laval, Québec, Canada G1K 7P4.
Lessard
P
P
Vandenberg
G
G
de la Noüe
J
J
D000704:Analysis of Variance; D000821:Animal Feed / Q000032:analysis / Q000382:microbiology*; D000818:Animals; D001823:Body Composition / Q000502:physiology; D001837:Body Weights and Measures; D004032:Diet; D056890:Eukaryota; D017686:Oncorhynchus mykiss / Q000254:growth & development*; D016019:Survival Analysis; D013696:Temperature; D013997:Time Factors