Effects of starvation on glycogen, lipids and protein content in juveniles of the red claw crayfish Cherax quadricarinatus.

NATALIA S. CALVO; FERNANDO CASTILLO DÍAZ; EDILMAR CORTÉS-JACINTO; LAURA S. LOPEZ GRECO.

San José

Congreso; TCS-ALCARCINUS Summer Meeting, Costa Rica 2013; 2013

The Crustacean Society

ver CD DEL CONGRESO PAGINA 165The ability to withstand and recover from periods of nutritional stress is an important adaptation forsurvival of any organism,mainly in freshwater. The point-of-no-return (PNR) is a threshold time atwhich initially starved animals have lost their capability to recover from nutritional stress, even if they are later fed ad libitum. The aim of this study is to describe the patterns of use of nutrient reserves nearby the PNR in Cherax quadricarinatus juveniles. In the two experiments juveniles were assigned to one of two groups: continuously fed (C) and continuously starved (S). Juvenile samples from each group were taken at days that correspond to PNR25 and PNR50. Samples were weighted, lyophilized and then, glycogen, total lipids and protein concentrations were estimated. In the first experiment, 800 early juveniles (14.8±0.18mg) were located on 16 aquaria and the samples were taken on days 8 and 9. In the second experiment, 80 advanced-juveniles (0.87±0.11g) were located on 16 aquaria and the samples were taken on days 40 and 50. In both experiments, dry weight, total lipids and glycogen from starved juveniles were lower than C. The protein content on early juveniles was similar between S and C along the experiments. However, in the advanced juveniles, protein level of S was similar to C on day 40 but lower on day 50. The results suggest that during starvation, juveniles of Cherax quadricarinatus use lipids and carbohydrate as their main energy source. Only nearby the PNR50, protein becomes a metabolic substrate on advanced juveniles.MINCYT-CONACYT MX/09/07. BID PICT 01187. UBACYT 2011-2014 (20020100100003)