魚粉の飼料効果に関する研究-II

Abstract

In this paper, the authors examined the digestibility of fish meal by a physiological method (with rainbow trout) and an artificial method (the pepsin method). Samples of white fish meal (flatfish) and brown fish meal (saury) were treated with or without several kinds of solvents (ether, petrolum ether, acetone, and benzene) separately, and stored in an oven thermostatically controlled at 30±1°C. before the test. The results obtained are as follows: 1) The digestibility of white fish meal for feeding on rainbow trout, as estimated physiologically is so high as about 80 to 85%, while the same of brown meal is about 50%, So, this may be one of reasons for low feed efficiency of the latter meal. Hence this type of meal contains some indigestible state of protein. 2) The digestibility estimated both by the pepsin method and the physiological method differs a little for white meal, having high digestibility, whereas, the corresponding difference is large in case of a brown meal, having low digestibility. 3) Whether in the pepsin method or in the physiological method, digestibility of white fish meal is hardly affected by subjecting it to the solvent extraction, while that of brown meal is somewhat increased by the same treatment.