Low fishmeal diets for Atlantic Salmon, Salmo salar L.,using soy protein concentrate treated with graded levels of phytase

• Published in: Aquaculture International
• Main Authors: Carter, CG, Sajjadi, M
• Format: Article in Journal/Newspaper
• Language: English
• Published: Kluwer Academic Publ 2011
• Subjects: Agricultural; Veterinary and Food Sciences; Fisheries sciences; Aquaculture; Atlantic salmon; Salmo salar
• Online Access: https://doi.org/10.1007/s10499-010-9358-z; http://ecite.utas.edu.au/71709

The experiment aimed at determining the efficient use of phytase (Phy) inAtlantic salmon diets that had low (4.5%) fishmeal and contained 60% soy protein concentrate(SPC). Phytase was either included at 250, 500, 1,000 or 4,000 U Phy kg-1 diet orthe SPC was pre-treated prior to making diets using 250, 500 or 1,000 U Phy kg-1 SPC. Fishwere fed the experimental diets for 12 weeks, and there were no differences in survivalamong treatments nor were there differences in growth performance between the phytasepre-treated SPC diets. Feed intake and weight gain were significantly lower for diets supplementedbelow 1,000 U Phy kg-1 compared to all other diets. Apparent digestibility (AD)of phosphorus was significantly lower without the use of phytase (45.43 +- 2.06%) than forall other treatments. AD phosphorus increased from 55.70 +- 1.81% at the lowest phytasesupplementation (250 U Phy kg-1) to 80.87 +- 2.12% at the highest (4,000 U Phy kg-1).There was no difference in AD phosphorus between the diet with the highest supplementation(4,000 UPhy kg-1) and the pre-treated diets. There were no differences in whole-bodydry material, crude protein or total lipid, whereas bone ash was significantly lower for dietssupplemented below 1,000 U Phy kg-1. Ash and phosphorus in the whole body and boneincreased with increasing added phytase. At and above an inclusion of 1,000 U Phy kg-1,bone ash (51.26 +- 0.12% bone weight) and bone phosphorus (11.21 +- 0.04% bone weight)reached concentrations that were no different to the pre-treated diets. In conclusion, phytaseimproved Atlantic salmon's growth performance fed low fishmeal diets containing SPC, andat least 1,000 U Phy kg-1 diet was required to have the same effect as pre-treatment of SPCwith 250 U Phy kg-1 SPC.