Posts

Vol.2 No.6 -6 : Survey on the parasites infested crayfish Procambarus clarkii, Girard,1852 (Crustacea, Cambaridae) in Egypt.

/0 Comments/in , , /by

By : Shimaa M. Abd El-Moaty, Hesham M. Sharaf, Abd El-Monem M.Khalil and Shimaa S. Ahmed.

Abstract

A parasitological survey on 1474 fresh water crayfish Procambarus clarkii was carried out during the period from January 2013 till May 2014 from different canals at Sharkia, Dakahlia and Kafr El-Sheikh Provinces in Egypt. Out of the examined crayfish , 8 were found to be infected with ectoparasitic protozoan Epistylis cambari on the gill filaments with percentage of infection 0.54% . Infection rates were varied between investigated areas, the percentages of infection were 0.21%, 0.57% and 2.7% at Sharkia, Dakahlia and Kafr El- Sheikh provinces respectively. Regarding to the seasonal prevalence of Epistylis cambari in examined crayfishes the peak of infection at Sharkia Province was recorded in summer (3.5%) , while at Dakahlia and Kafr El- Sheikh Provinces was detected in spring (1.13%) and (5.12%) respectively. The present study revealed that 11 out of 1474 (0.88%) were infected by one or more parasitic nematode larvae Strongyloides stercoralis that were observed in hemoceol of crayfish .The percentages of infection were 0.31%, 2.3% and 1.3% at Sharkia, Dakahlia and Kafr El-Sheikh Provinces respectively. Concerning to the seasonal prevalence of nematode larvae in examined crayfish, the peak of infection at Sharkia Province was detected in spring (4.5 %) ,while at Dakahlia Province was in summer (3.2%) and at Kafr El-Sheikh Province was in spring (1.5%). No infection was detected in winter and autumn.

6. Survey on the parasites infested crayfish Procambarus clarkii, Girard,1852 (Crustacea, Cambaridae) in Egypt.
Download Issue

Vol.1 No.2 -2 : Effect of starvation and drought on the activity of the freshwater crayfish, Procambarus clarkii.

/0 Comments/in , , /by

By : Gamalat Y. Osman, Mansour A. Galal, Sherin K. Sheir* and Mona M. Soliman

Abstract

This study was designed to investigate the effect of starvation and drought on the adult Procumbarus clarkii. Samples were captured from the River Nile, Dakahleyia province, Egypt. Measurements were the animal weight and length and survival rate. The experiment was divided into four groups, control with food and water, starved with water only, drought with food only and starved – drought without any food or water groups. Crayfishes showed great tolerance for 14 weeks (P < 0.05). The body weight of the crayfish was more affected than the body and carapace lengths due to the loss of its chelae during starvation. In the starved groups, survival rate of the crayfish declined because its aggressive behavior such as killing each others (66.6%). Crayfishes could not tolerate drought for a long time (5 days). The body weight, length, and the carapace length were minimally influenced during drought, while the survival rate was dramatically affected within few days. The combined effect of both stressors affected the animal survival more drastically within four days (100, 50 and 0%). It can be concluded that starvation and drought caused serious changes in P. clarkii behavior, biometry and survival rate, which determine the ability of crayfish to adapt to one or more of the environmental changes.

2. Effect of starvation and drought on the activity of the freshwater crayfish, Procambarus clarkii.
Download Issue