The partial and total replacement of fishmeal with selected plant protein sources in diets for the south African abalone, Haliotis midae L.

摘要

As protein is the most expensive nutrient to supply in abalone feeds, it is necessary to evaluate the relative performance of different protein sources in formulated diets. Fourteen diets were formulated to contain 34 percent crude protein and 6 percent lipid. These were fed to juvenile abalone, Haliotis midae (initial shell length: 10.6 +- 0.1 mm). Dietary fishmeal was substituted at 30, 50, 75, or 100 percent with plant protein concentrates, and the growth and nutritional parameters were recordedover a 180-day growth period. No significant differences were found in the growth rates between the control diet (100 percent fishmeal) and diets in which 30 percent of the fishmeal component had been replaced by either soy or sunflower meals, or torulayeast (P > 0.05). Substitution of 50 percent fishmeal with either soya meal or spirulina did not affect growth rates (P > 0.05). Replacement of either 75 or 100 percent of the fishmeal with plant protein sources had a significant affect on growth (P < 0.05). Pearson product moment correlations between dietary lysine levels and either growth rates or protein efficiency ratios revealed positive correlations (r = 0.75, P < 0.002; r = 0.88, P < 0.0001, respectively), suggesting that lysine may have been the first limiting amino acid in these diets. Carcass analysis revealed that dietary protein source had no significant affect on body composition (P > 0.05).