Inducing Molting by Eyestalk Ablation in the Red Swamp Crayfish, Procambarus clarkii from the Egyptian Freshwaters

Abstract

See, stats, and : https : / / www . researchgate . net / publication / 305913419 Inducing Red , Procambarus the Article DOI : 10 . 11648 / j . ajls . s . 2015030601 . 20 READS 3 4 , including : Mohamed Al - Azhar 5 SEE All - text , letting . Available : Mohamed Retrieved : 09 American Journal of Life Sciences 2015 ; 3 (6 - 1) : 69 - 75 Abstract : Eyestalk ablation was used for inducing molting in the freshwater crayfish , Procambarus clarkii at the laboratory conditions . The results exhibited that , both of unilateral and bilateral eyestalk removal accelerated molting rate than in non - ablated or intact individuals of this species . The use of unilateral eyestalk removal has low effect , induced molting at the 6 th week and reached 100% at the end of the 16 th week , compared with starting molting at the 8 th week for control , which did not exceed than 40 % for molted individuals at the end of experiment , with 20% mortality for each . On contrast , the bilateral ablation has high effects and induced molting rapidly at the first and second weeks for the two experiments . It was associated with high mortality rates , averaged 28 . 33%for ablated individuals of the two experiments , increased gradually to 51 . 67%and 80 . 0% for individuals of the premolt stages , which showed signs of molting but were unable to complete molting cycle and died at the end of the last week of each experiment . Repeating molting was recorded for only one bilateral ablated animal after 11 days , but no molting was noticed for control group , with mortality of 20 % . The percentages of increments in body dimensions included body length , carapace length , chelae length and total body weight were calculated . Most ratios of increments , except only total body weight , were high in ablated males than ablated females , as well as clearly higher in normal molted males and females than ablated ones , but declined sharply to 3 . 30±2 . 91% in total body weight for bilateral ablated males .