A comparison of the effect of diet extrusion or screw-press pelleting on the digestibility of grain protein products when fed to rainbow trout (Oncorhynchus mykiss)

This study examined the effect of the extrusion process on the digestibilities of whole diets and also the component test ingredients when fed to rainbow trout. Six diets were prepared using either a screw-press or an extruder based on the same batches of raw materials in each case.