The Growth Rate of Brown Trout (Salmo trutta L.) Fed on Maximum Rations

TLDR

Prior reviews have examined factors influencing fish growth and feeding, particularly in salmonids, and this study is part of a series on brown trout feeding and growth. The study aims to determine growth rates of brown trout when fed maximum rations. Experiments were conducted and a mathematical model was developed to estimate maximum growth rates for trout of varying sizes at different temperatures. The model produced estimates of gastric evacuation time, satiation amount, meal duration, daily food intake, and maximum feeding rate for trout weighing 10–350 g across a range of temperatures.

Abstract

The many factors affecting the growth and feeding of fishes have been reviewed by Brown (1957), Ivlev (1961), Paloheimo & Dickie (1965, 1966a, b) and Phillips (1969). These reviews include the relevant work on salmonids and the only important addition is the work on sockeye salmon (Oncorhynchus nerka Walbaum) by Brett, Shelbourn & Shoop (1969) and Brett (1971). The present paper is one of a series dealing with feeding and growth in brown trout (Salmo trutta L.). From the results of previous work, it is now possible to estimate the rate and time for the gastric evacuation of different meals (Elliott 1972), the maximum weight of food consumed in a meal (satiation amount) and the time taken to eat this meal (Elliott 1975a), the maximum weight of food consumed in a day and the maximum rate of feeding (Elliott 1975b). These estimates are applicable to trout of different weights (approximate range 10-350 g live weight) at different water temperatures (range 3-821-6? C). The next stage was to examine the growth rates of trout fed on maximum rations. These experiments are described in the present paper and a mathematical model is developed to estimate maximum growth rates of different sized trout at different temperatures.