64 Molluscicidal activity of Makabuhay (Tinospora rumphii Boerl) stem ethanolic extract against Radix (Lymnaea) spp. snails Marshal G. Esquilla 1 , Carlito B. Sanchez 1 , Jan Clyden B. Tenorio 2,* 1 Department of Veterinary Clinical Sciences, College of Veterinary Medicine, University of Southern Mindanao, Kabacan 9407, Cotabato, Philippines 2 Department of Veterinary Paraclinical Sciences, College of Veterinary Medicine, University of Southern Mindanao, Kabacan 9407, Cotabato, Philippines *Corresponding author: jcbtenorio@usm.edu.ph | Received: 18 June 2021 | Accepted: 23 August 2021 | Published Online: 27 August 2021 | How to cite Esquilla MG, Sanchez CB, Tenorio JCB. 2021. Molluscicidal activity of Makabuhay (Tinospora rumphii Boerl) stem ethanolic extract against Radix (Lymnaea) spp. snails. J New Biol Rep 10 (2): 64 – 71. ABSTRACT Lymnaeid snail infestation and snail-borne parasitic diseases, such as fasciolosis, remain a problem in the livestock industry in the Philippines. Effective molluscicides are thus needed. However, the routine application of commercially available molluscicides may cause unwanted environmental contamination. Natural alternatives to commercially available molluscicides are called for, thus, this study investigated the molluscicidal activity and efficacy of makabuhay (T. rumphii) ethanolic stem extract against lymnaeid snails. A total of 150 mature snails from Barangay Guiamalia, Esperanza, Sultan Kudarat were subjected to immersion bioassay with T. rumphii ethanolic extracts. There were five treatment groups: Treatment A or negative control (100% tap water), Treatment B (5 000 ppm), Treatment C (7 500 ppm), Treatment D (10 000 ppm) and Treatment E or positive control (10 000 ppm Surekill® 70WP). Snail death was measured 24-, 48- and 72- hours post-exposure. The results revealed a 100% treatment-specific mortality in all T. rumphii extract concentrations, and in the positive control at 24-hours post-treatment. Treatments B, C, D and E had an excellent efficacy of 96.67%. These results show that T. rumphii ethanolic extracts at 5 000 ppm, 7 500 ppm and 10 000 ppm concentrations are effective natural molluscicides against lymnaeid snails. The promising results suggest that T. rumphii stem ethanolic extract may be an excellent natural, inexpensive alternative to commercially available molluscicides. Key words: Makabuhay, Panyawan, Tinospora rumphii, Natural Molluscicide, Radix spp., Molluscicide efficacy. INTRODUCTION Lymnaeid snail (Radix spp.) infestation is a burden to farmers that are engaged with livestock production. The snail serves as an intermediate host of Fasciola hepatica and F. gigantica in the Philippines (Tenorio & Molina 2021). Fasciolosis is parasitic disease that may cause grave economic losses to cattle, water buffalo, sheep, and goat farmers in the country (Molina et al. 2005; Portugaliza et al. 2019). With the presence of such diseases, animal condition will be affected and production will decline (Molina et al. 2005; Mazeri et al. 2017). In the veterinary practice, taking out the lymnaeid snail is an effective form of disease prevention which lead to the economic benefit of more productive animals. There are several methods to eliminate snail population and one method of choice is application of commercially available molluscicides. However, according to Coelho & Caldeira (2016) these products have multiple lethal effects on other organisms and, aside from being expensive, they require frequent applications to reduce snail population. In the Philippines, control of lymnaeid snails using indigenous plants is an option that farmers can adapt. Thus, these native plants must be studied for their potential molluscicidal activity against snail vectors of economically important veterinary diseases. Published by www.researchtrend.net Journal on New Biological Reports JNBR 10 (2) 64 – 71 (2021) ISSN 2319 – 1104 (Online)