The use of silage made from fish and abalone viscera as an ingredient in abalone feed

Silage prepared from fish and abalone viscera are effective dietary protein sources for the juvenile abalone, Haliotis fulgens. Significantly higher growth rates occurred when abalone were fed artificial diets containing heated fish silage (53 mu m day(-1)) and unheated fish silage (61 mu m day(-1)) as a protein source compared with the kelp, Macrocystis pyrifera (1.5 mu m day(-1)). However, no differences were found between diets containing heated and unheated fish silage at 30% protein inclusion, suggesting that the degree of hydrolysis did not affect protein utilization by abalone. Similar results were obtained when abalone viscera silage was used (50 mu m day(-1)), producing faster growth rates than kelp (18 mu m day(-1)) or kelp meal (12 mu m day(-1)). In the same experiment a significant increase in growth rate was observed when at,alone with low growth rates, resulting from feeding on kelp and kelp meal, were switched to a diet containing abalone viscera silage. These animals exhibited higher growth rates (135 and 167 mu m day(-1)) than animals fed this diet throughout the trial (122 mu m day(-1)), suggesting the presence of compensatory growth of organisms.