Study of mycoflora in the Persian sturgeon (Acipenser persicus) eggs and in incubation water

Objective: As information on the fungal flora during different stages of breeding and rearing sturgeons is very scarce, the present study was conducted to quantify and characterize the microflora associated with Acipenser persicus eggs and incubation water in the Shahid Beheshti Hatchery. Method & Materials: Egg samples (20-30 eggs) and water samples (25 cc) were collected in three phases (0, 48 and 96 h after fertilization). Three replicates were used for each sample in each phase. Egg samples were collected in sterile glass containers and water samples were collected in sterile test tubes and transferred to the laboratory where the fungal flora was isolated, identified and counted. A suspension was prepared of the egg and water samples that were diluted under sterile conditions and inoculated on SDA+C culture medium. Results & Conclusion: Fungal flora found on egg samples in order of their frequency were as follows: Penicillium (28%) Cladosporium (28%), Fusarium (10%), Yeast (5%), Mucor sp.(5%), Alternaria (10%) and Paecilomuces (14%). In water samples fungal flora were Penicillium (49%), Cladosporium (18%), Fusarium (11%), Alternaria (4%), Mucor sp. (7%), Paecilomyces (7%) and Yeast(4%). Saprolegnia sp. was isolated in the eggs as well as water samples studied. It is evident from the results obtained that the fungal flora observed in eggs is similar to that observed in incubation water samples. No significant differences (ANOVA) were detected in the total fungal flora in eggs (P>0.05) and incubation water (P>0.05) in the three phases studied. Also T-test conducted indicated no significant differences in total fungal flora in eggs (11.66 ± 9.57; 2-36 Colony forming unit; CFU) and in water (17 ± 10.23; 4-44 CFU) samples. However, positive correlation (P<0.01; r=0.476) was detected between the total fungal flora in egg and water samples.

کلیدواژه ها:

Mycoflora ، Acipencer percicus ، Egg ، Egg water ، CFU