Identification of Causative Agent for Fungal Infection and Effect of Disinfectants on Hatching and Survival Rate of Bata (Labeo. Bata) Larvae
2017; MedCrave Group; Volume: 7; Issue: 4 Linguagem: Inglês
10.15406/apar.2017.07.00264
ISSN2373-6402
Autores Tópico(s)Leech Biology and Applications
ResumoLabeo.bata is one of the most important cultured fish.Intensive incubation leads to microbial overgrowth in L. bata eggs that hamper egg development hatchability and larval survivability.The aim of this study is to find out causes of mass mortality in L. bata eggs during peak breeding season from 10 March to May 2015 at Mafatema Fish Hatchery Jessore Bangladesh.Three concentrations of four chemical-formalin (10 20 30 mg/L) malachite green (135 mg/L) NaCl (123 g/l) and methylene blue (135 mg/L) treatment regimes and a control were compared for efficacy in treating L. bata eggs to prevent fungus and bacterial infection and improve hatch and survival rate of fry.Physicochemical and microbial characteristics of culture water were examined during the induced breeding of L. bata besides mycological examination of egg samples with trial of treatment of different types of disinfectant.The total bacterial count fluctuated between 3.6×10 8 cfu/ml at initial time of incubation and 31.7×10 8 cfu/ml after 3 days of hatching.The infected fertilized egg by Saprolegnia sp. were appeared as tuft hairy like balls with a white cottony envelope that surround it which focally invaded the cytoplasm resulted in loss of the cytoplasm content and destructed envelops.Hatching rate (92.33±3.51%) of methylene blue at 1mg/L was significantly different with formalin at 10mg/L (78.0±5.29%) and control (72.33±5.51%)at.05 level of significance.Survival rate of malachite green at 5mg/L (87.33±6.51%)NaCl at 2g/L (91.00±3.00%)and methylene blue at 1mg/L (94.33±4.73%)had significant difference with control (71.00±8.89%)at.05 level of significance.
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