Effect of different diets on digestive enzyme activities, in vitro digestibility, and midgut gland structure in juvenile crayfish, Cherax quadricarinatus

Abstract

Sacrist an, H.J., Fern andez-Gimenez, A.V., Chaulet, A., Franco Tadic, L.M., Fenucci, J. and L opez Greco, L.S. 2015. Effect of different diets on digestive enzyme activities, in vitro digestibility, and midgut gland structure in juvenile crayfish, Cherax quadricarinatus. -Acta Zoologica (Stockholm) 00: 000-000.This study investigated the effects of food quality on digestive enzyme activities, in vitro protein digestibility and histological traits of the midgut gland in juvenile crayfish Cherax quadricarinatus. Animals of a wide weight range were fed different diets: two commercial diets with high or low lipid content (high lipid and low lipid, respectively) and were compared with a reference diet (RF) previously formulated for this species. Proteinase, lipase and amylase activities were significantly influenced by diet and weight. Specific trypsin activity was significantly higher for crayfish fed with the HL diet. Trypsin activity depended on diet and weight. Protein digestibility showed that HL was the most digestible diet and RF the least. The weight of the animals did not affect protein digestibility. Structural disorganization, hypertrophy of B-cells and presence of large vacuoles in R-cells were mainly observed in juveniles fed with HL, indicative of malnutrition. Thus, our data suggest that the HL diet would not be the most appropriate for C. quadricarinatus, while RF diet would be more convenient for culture of this species.

From fish‐processing waste to feed additives for crayfish

“…However, a formulated feed for redclaw crayfish is not available in South America, so producers usually produce their own diet or use one that is formulated for trout (Fundus®). Sacristán et al () evaluated this diet and demonstrated that it is not suitable for C. quadricarinatus juveniles as they observed malnutrition signs in the midgut gland structure. In addition to this drawback, the cost of the commercial fish meal used as the main component of feed formulations is continuously increasing, while its market supply displays a considerable variation in quality.…”

“…So far, a 100% efficient protein digestion has never been described, and such digestion effectiveness varies according to the protein source supplied (Sacristán et al, ; Smith, Lee, Lawrence, & Strawn, ). Thus, the expected future growth of the aquaculture sector increases the pressure to maximize feed utilization.…”

The redclaw crayfish: A prominent aquaculture species with invasive potential in tropical and subtropical biodiversity hotspots

“…2016). Despite the delay in mortality (as shown, e.g., for yabby; Unestam, 1975), redclaw appears to be susceptible (Unestam 1975b; Roy 1993; Stephens et al . 2005) and can exhibit high mortality rates in aquaculture (Marino et al .…”

Growth and health status of the red claw crayfish, cherax quadricarinatus , fed diets with four typical plant protein sources as a replacement for fish meal

“…Diets currently used for red claw crayfish rely mostly on diets from shrimps, primarily Litopenaeus vannamei , Penaeus monodon and Macrobrachium rosenbergii , and even on fish diets (Saoud et al, 2013). Progress in the development of commercial feed for red claw crayfish has been made over the past decade, but many knowledge gaps still exist in nutrient requirements, which need to be researched extensively and deeply (Cortés‐Jacinto et al, 2003; Sacristán et al, 2016; Thompson et al, 2005).…”