ÉVALUATION DE DIVERS TRAITEMENTS TECHNOLOGIQUES DES CÉRÉALES VII. — UTILISATION DE MAÏS PRESSÉ, FLOCONNÉ, EXPANSÉ ET EXTRUDÉ DANS L'ALIMENTATION DE LA TRUITE ARC-EN-CIEL

Abstract

Rainbow-trout were fed for 20 wk, diets of .apprx. 40% whole maize previously subjected to the following treatments: pelleting, flaking, popping or extrusion. Growth and feed conversion ratios of the corresponding groups were compared with those obtained in trouts receiving untreated maize. Weight gain improved after popping and extrusion of the maize (14 and 8%, respectively); pelleting did not lead to any improvement as compared to the controls, feed conversion and protein efficiency ratios, only varied from 1.04 to 1.07 and from 2.33 to 2.41%, respectively. The amounts of perivisceral depot fats increased following flaking, popping and extrusion of the maize. The favorable action of these treatments seems to be due to an improvement of starch digestibility, but the eventual effect on the other constituents of this cereal is uncertain.