Trials of Niclosamide on Fresh Water Snails and Its Impact on Water Quality
K. P. Singh
School of Wildlife Forensic and Health, Nanaji Deshmukh Veterinary Science University, Jabalpur 482001, India.
Devendra Podhade *
School of Wildlife Forensic and Health, Nanaji Deshmukh Veterinary Science University, Jabalpur 482001, India.
Nidhi Rajput
School of Wildlife Forensic and Health, Nanaji Deshmukh Veterinary Science University, Jabalpur 482001, India.
Amol Rokde
School of Wildlife Forensic and Health, Nanaji Deshmukh Veterinary Science University, Jabalpur 482001, India.
*Author to whom correspondence should be addressed.
Abstract
Background: The study aimed to evaluate the molluscicidal efficacy of niclosamide against freshwater snails and assess its residual effects on water quality, aquatic flora, and fauna under field conditions.
Study Design: Field-based experimental study involving treated and untreated water bodies.
Place and Duration of Study: The study was conducted over two years within the 2022-2025 period in rainy-season ditches, marshy areas, stagnant water pockets, and artificial water holes within a protected chain-link-fenced area at Central Jail Road, Jabalpur 482001.
Methodology: Field trials were conducted in rainy-season ditches and marshy lands, with cement tanks kept for control measures. Niclosamide was used at a concentration of 4 mg/L by spray and bag-tagging methods against Indoplanorbis exustus and Lymnaea luteola water snails that naturally breed in the rainy season water pockets. Snail mortality was recorded at different intervals following treatment. Water quality parameters, including pH, dissolved oxygen, conductivity, salinity, orthophosphates, and total dissolved solids, were assessed before and after treatment. The residual effects on aquatic weeds and other aquatic fauna were also evaluated.
Results: Niclosamide treatment produced substantial mortality among freshwater snails. The spray method resulted in 95–98% mortality, whereas the bag-tagging method produced approximately 40–50% mortality. Mortality was particularly pronounced during the first 1–7 days after treatment. No significant adverse changes were observed in major water-quality parameters, although minor variations in pH, dissolved oxygen, conductivity, salinity, orthophosphates, and total dissolved solids were recorded. No apparent residual effects were observed on aquatic weeds and tadpoles.
Conclusion: Niclosamide at 4 mg/L demonstrated high molluscicidal efficacy against I. exustus and L. luteola under field conditions, particularly when applied by the spray method. Its limited residual impact on water quality and non-target aquatic organisms indicates its potential for managing freshwater snail populations in stagnant water bodies and reducing the risk of fluke-borne diseases in wild and domestic herbivores.
Keywords: Field trial, niclosamide, molluscicide, water holes, water snails