author(s)
Pawan Kumar Sharma, J Stephan Sampath Kumar, GK Shiv Raman, V Senthil Kumar, S Anand, Chandana BL and Gayatri Pandey

abstract
The commercialization and intensification of aquaculture demand use of drugs. This study was carried out in two districts of Kerala (Ernakulum and Kottayam) and Tamil Nadu (Thanjavur and Trichy) from October 2018 to March 2019 through interaction with the farmers. Structured questionnaire was prepared and used. The calculations were done in MS excel and the data processed. Farmers of Kottayam District of Kerala were found to consult the fisheries officials but only 56.25% farmer’s analysed water and soil quality regularly. The use of medicines and chemicals was 6.25% higher in Ernakulum than Kottayam District. Only 20% farmers of Ernakulum and 12.50% of farmers in Kottayam invested less than Rs 1, 000 towards chemical or medicines. Compared to Kottayam, 01 to 04% more farmers had a 1-ha fish farm in Ernakulum district. In these districts, the farmers stock their ponds with Indian and exotic carps, tilapia, pearl spot besides shrimps. In Ernakulum district, the use of KMnO4, bleaching powder and salt is common as a medicine or chemical for fish diseases while in Kottayam district the use of NUAN, KMnO4, CuSO4, FeSO4 and bleaching powder is common. The frequency of regular monitoring the water quality was 16.25% higher with the farmers of Kottayam district than those of Ernakulum district. The farm ponds of Thanjavur district were managed under the Irrigated Agriculture Modernization Project while those in Trichy were managed under the Multi-purpose Farm Pond Scheme (2017-18) where occurrence of diseased fish was negligible as these farmers are getting quality seed from the Fisheries Department that is healthy and fingerling size (>5cm). Finally It is thus obvious that better management practices (BMP) under monitoring of aquaculture units by fisheries departments and research and academic institutions may minimize disease occurrence and thereby improve the production also.