| Sumario: | A strain of rainbow trout (CX strain) at the Hagerman Fish Culture Experiment Station has been selected for growth on a plant-based diet for ten generations. We Compared fish from the CX strain that were age (CXA) and size (CXS) matched to three commonly available commercial strains selected for growth (RBT1, RBT2, RBT3). We compared differences in overall growth, oxidative stress and intestinal inflammation between fish fed a fishmeal (FM) or soybean-meal (SBM) diet for 12 weeks. Fish of each strain were randomly assigned to FM or SBM diet groups and fed daily to satiation. Tissues from each experimental group were sampled every four weeks to assess gene expression and growth parameters. Both CX strains had higher growth rates compared with similar feed consumption among all groups. Expression of intestinal and hepatic biomarkers for oxidative stress varied between liver and intestine. Expression varied between CXA and CXS fish despite being from the same strain indicating size at age affects gene expression and care should be taken when comparing different strains with different growth rates. Expression of calcium binding protein S100I2 in the intestine was elevated initially at 4 weeks, diminished at 8 weeks, then elevated again by 12 weeks. This pattern was also observed in intestinal SOD expression and GPx expression in the liver. Overall, these results provide further information on current commercial strains of rainbow trout to help improve the utilization on plant protein sources in their diets.
|
|---|
