Investigating water quality and disease in white leg shrimp (Penaeus vannamei) culture applying Nanobubble technology

Abstract

This study evaluates the variation of water quality, microbiology, gill morphology and shrimp growth of the intensive white leg shrimp (Penaeus vannamei) applying Nanobubble technology. The experiment consisted of 9 commercial concrete tanks with a volume of 25-35 m³ divided into 3 treatments of oxygen Nanobubble (O₂-NB), ozone Nanobubble (O₃-NB), and control (CTRL), 3 tanks for each treatment. O₂-NB and O₃-NB were provided to the tanks for 1 hour/day during the culture period from stocking to harvest. Shrimps were stocked at a density of 300 shrimp/m³ and applied with the same care and environmental management protocol such as feeding, water change, aeration, siphon, and microbiological treatment. The results showed that the pH, DO, and ORP parameters are affected by the O₂-NB and O₃-NB treatments. The average concentration of total Vibrio in the water of the O₂-NB group was 1.41 times higher than that of the control group, and 1.51 times higher than that of the O₃-NB group. The gill tissue of the shrimp was affected and changed to different degrees but did not reduce the survival rate of the shrimp in the experimental treatments. The harvest weight of shrimp of the control, O₂-NB, and O₃-NB treatments were 11.50±2.29, 11.48±2.66, and 13.87±1.65 g/shrimp, respectively. Research results exhibited that O₃-NB treatment increased DO, reduced total Vibrio in water and increased growth rate compare to the control and O₂-NB treatments. Reducing Nanobubble generator running time should be considered to minimise the impact on shrimp gills.