Apparent dry matter and protein digestibility of vegetal and animal ingredients and diets for pre-adult Australian redclaw crayfish Cherax quadricarinatus (von Martens 1858)

Abstract

Apparent dry matter and protein digestibility of four animal and three vegetal ingredients and diets with them included, were evaluated for pre-adult Cherax quadricarinatus. The ingredients were: two sardine meals (67% and 58% crude protein), squid meal, red crab meal, soy paste, textured wheat, and sorghum meal. A reference and seven experimental diets were formulated including 14.5% of each ingredient in the reference diet, and 0.5% of chromic oxide as a marker. Vegetal ingredients and the corresponding diets, had higher digestibility than animal ingredients. Textured wheat, soy paste, and sorghum meals showed an excellent dry matter/digestibility (> 86%). The digestibility of protein was better in textured wheat, and soy paste meals (> 87%). Some animal ingredients such as, squid meal, and sardine meal 67% CP, had acceptable dry matter digestibility (over 65%). It is concluded that pre-adult redclaw is omnivorous and able to efficiently consume vegetal and animal ingredients, but they can digest better the vegetal ingredients.