Egg surface decontamination with bronopol increases larval survival of Nile tilapia, Oreochromis niloticus

Intensive tilapia egg incubation techniques create favourable conditions for microbial proliferation which often leads to massive mortalities of fish larvae. The effects of Nile tilapia (Oreochromis niloticus) eggs exposure to bronopol on decontamination of their bacterial surface and survival of la...

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Main Authors: S. Jantrakajorn, J. Wongtavatchai
Format: Article
Language:English
Published: Czech Academy of Agricultural Sciences 2015-10-01
Series:Czech Journal of Animal Science
Subjects:
Online Access:https://cjas.agriculturejournals.cz/artkey/cjs-201510-0002_egg-surface-decontamination-with-bronopol-increases-larval-survival-of-nile-tilapia-oreochromis-niloticus.php
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author S. Jantrakajorn
J. Wongtavatchai
author_facet S. Jantrakajorn
J. Wongtavatchai
author_sort S. Jantrakajorn
collection DOAJ
description Intensive tilapia egg incubation techniques create favourable conditions for microbial proliferation which often leads to massive mortalities of fish larvae. The effects of Nile tilapia (Oreochromis niloticus) eggs exposure to bronopol on decontamination of their bacterial surface and survival of larvae were observed. Immersion treatments of fertilized eggs were applied at 10, 25, 50, 100, and 250 mg/l of bronopol for 10, 20, and 30 min. This treatment substantially reduced the number of bacteria on Nile tilapia eggs. The greatest reduction in bacterial numbers (1.58 × 103 colony forming units/g of egg) was observed at the maximum treatment dosage, i.e. 250 mg/l for 30 min, but this was not significant when compared with treatments of 100-250 mg/l bronopol for 10-30 min. Treatments of 50-250 mg/l bronopol provided better larval survival (89.33-94.67%) than those of < 50 mg/l (P < 0.05). The larval survival obtained from the Nile tilapia eggs disinfected with 10 and 25 mg/l bronopol for 10-30 min was similar to that of negative controls (79.33-80.97%). Additional in vitro test was performed to determine the inhibitory potency of bronopol against bacteria cultured from fertilized Nile tilapia eggs. Twenty-two bacterial isolates (Aeromonas hydrophila (n = 12), Staphylococcus aureus (n = 6), Escherichia coli (n = 2), and Micrococcus spp. (n = 2)) responded to minimum inhibitory concentrations of bronopol ranging from 64 to 128 µg/ml. The study demonstrates that the immersion treatment of Nile tilapia fertilized eggs with 250 mg/l for 10-30 min, the concentration proven effective against bacteria cultured from fertilized eggs, significantly reduced bacterial load and improved larval survival.
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spelling doaj.art-769c63ded94c4581b1b930ddece5c43b2023-02-23T03:33:19ZengCzech Academy of Agricultural SciencesCzech Journal of Animal Science1212-18191805-93092015-10-01601043644210.17221/8523-CJAScjs-201510-0002Egg surface decontamination with bronopol increases larval survival of Nile tilapia, Oreochromis niloticusS. Jantrakajorn0J. Wongtavatchai1Faculty of Veterinary Science, Prince of Songkla University, Songkhla, ThailandDepartment of Veterinary Medicine, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, ThailandIntensive tilapia egg incubation techniques create favourable conditions for microbial proliferation which often leads to massive mortalities of fish larvae. The effects of Nile tilapia (Oreochromis niloticus) eggs exposure to bronopol on decontamination of their bacterial surface and survival of larvae were observed. Immersion treatments of fertilized eggs were applied at 10, 25, 50, 100, and 250 mg/l of bronopol for 10, 20, and 30 min. This treatment substantially reduced the number of bacteria on Nile tilapia eggs. The greatest reduction in bacterial numbers (1.58 × 103 colony forming units/g of egg) was observed at the maximum treatment dosage, i.e. 250 mg/l for 30 min, but this was not significant when compared with treatments of 100-250 mg/l bronopol for 10-30 min. Treatments of 50-250 mg/l bronopol provided better larval survival (89.33-94.67%) than those of < 50 mg/l (P < 0.05). The larval survival obtained from the Nile tilapia eggs disinfected with 10 and 25 mg/l bronopol for 10-30 min was similar to that of negative controls (79.33-80.97%). Additional in vitro test was performed to determine the inhibitory potency of bronopol against bacteria cultured from fertilized Nile tilapia eggs. Twenty-two bacterial isolates (Aeromonas hydrophila (n = 12), Staphylococcus aureus (n = 6), Escherichia coli (n = 2), and Micrococcus spp. (n = 2)) responded to minimum inhibitory concentrations of bronopol ranging from 64 to 128 µg/ml. The study demonstrates that the immersion treatment of Nile tilapia fertilized eggs with 250 mg/l for 10-30 min, the concentration proven effective against bacteria cultured from fertilized eggs, significantly reduced bacterial load and improved larval survival.https://cjas.agriculturejournals.cz/artkey/cjs-201510-0002_egg-surface-decontamination-with-bronopol-increases-larval-survival-of-nile-tilapia-oreochromis-niloticus.phpbacteriadesinfectantegg disinfectiontilapia egg
spellingShingle S. Jantrakajorn
J. Wongtavatchai
Egg surface decontamination with bronopol increases larval survival of Nile tilapia, Oreochromis niloticus
Czech Journal of Animal Science
bacteria
desinfectant
egg disinfection
tilapia egg
title Egg surface decontamination with bronopol increases larval survival of Nile tilapia, Oreochromis niloticus
title_full Egg surface decontamination with bronopol increases larval survival of Nile tilapia, Oreochromis niloticus
title_fullStr Egg surface decontamination with bronopol increases larval survival of Nile tilapia, Oreochromis niloticus
title_full_unstemmed Egg surface decontamination with bronopol increases larval survival of Nile tilapia, Oreochromis niloticus
title_short Egg surface decontamination with bronopol increases larval survival of Nile tilapia, Oreochromis niloticus
title_sort egg surface decontamination with bronopol increases larval survival of nile tilapia oreochromis niloticus
topic bacteria
desinfectant
egg disinfection
tilapia egg
url https://cjas.agriculturejournals.cz/artkey/cjs-201510-0002_egg-surface-decontamination-with-bronopol-increases-larval-survival-of-nile-tilapia-oreochromis-niloticus.php
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AT jwongtavatchai eggsurfacedecontaminationwithbronopolincreaseslarvalsurvivalofniletilapiaoreochromisniloticus