Characterization of the Molt Stages inPenaeus vannamei: Setogenesis and Hemolymph Levels of Total Protein, Ecdysteroids, and Glucose

Abstract

The molting cycle of Penaeus vannamei juveniles was characterized by distinct and predictable changes in the setae of pleopods. The molt pattern was diecdysic with a relatively short intermolt period (40%) and a long proecdysial period (>53%). The levels of both total protein and ecdysteroids increased in the hemolymph during proecdysis, whereas the level of hemolymph glucose was low at metecdysis and proecdysis and maximal during anecdysis. As revealed by SDS-PAGE, the relative concentrations of two polypeptides (32 kD;

Cloning of a shrimp (Metapenaeus ensis) cDNA encoding a nuclear receptor superfamily member: an insect homologue of E75 gene1

“…The molt stages of these shrimp were identi¢ed by pleopod setogenesis [8]. Brie£y, a small piece of pleopod (swimming leg) was cut and setal development was observed under the microscope.…”

Determination of moult stage in the South African West Coast rock lobster Jasus lalandii (h. Milne Edwards) (Crustacea: Decapoda)

“…Based on integumental changes, Drach (1939 as cited by Chan et al 1988) first divided the crustacean moult cycle into four phases: metecdysis (subdivided into Stages A and B), the period immediately following ecdysis; anecdysis (Stage C), a period of tissue growth and accumulation of food reserves; proecdysis (Stage D), a period of active morphological and physiological change in preparation for the next moult; and ecdysis (Stage E), the shedding of the old cuticle.…”

Effect of dietary chitin on digestive enzyme activity, growth and survival of Macrobrachium tenellum juvenile prawns

“…As Lemos et al (2000) find, different growth stages engenders different feeding behavior and different digestion tract functional structures, thus, different digestion capabilities. This contributes to differences in enzyme activity, as observed in shrimp by Chang et al (1988). Casillas-Hernández et al (2002) observe that enzymatic, hormonal, and environmental issues are involved with molting, causing an indirect effect on growth rate.…”

“…Most of the works on the effect of chitin in the diet of crustaceans have been developed with penaeid species (Chang et al, 1988;Shiau & Yu, 1998;Terwilliger, 1999;Chang et al, 2001;CasillasHernández et al, 2006;Chih-Hui & Chen-Chun, 2012). For Macrobrachium prawns, Kumár et al (2006) compared the effect of natural chitin and purified chitin on the growth of Macrobrachium rosenbergii (De Man, 1879).…”