MOHAMMAD MAMUN CHOWDHURY*, MD. RAKNUZZAMAN AND KAZI FARHED IQUBAL 1 Department of Fisheries, University of Dhaka, Dhaka-1000, Bangladesh

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1 Bangladesh J. Zool. 34(1): , 2006 CONTROL OF ARGULUS SP. INFESTATION IN GOLDFISH (CARASSIUS AURATUS) WITH SUMITHION MOHAMMAD MAMUN CHOWDHURY*, MD. RAKNUZZAMAN AND KAZI FARHED IQUBAL 1 Department of Fisheries, University of Dhaka, Dhaka-1000, Bangladesh Abstract: An effective dose of organophosphate pesticide, Sumithion was determined in controlling Argulus sp. infection in Goldfish (Carassius auratus) bought from market. The fishes were reared in laboratory condition maintaining the following physico-chemical variables: water temperatures varied from ± 0.55 to ± C, DO ranged from 6.32 ± 0.15 to 6.80 ± 50 mg/l, free CO 2 ranged from ± 0.12 to ± 0.50 mg/l and ph varied from 7.60 ± 0.30 to 7.70 ± Four dosages were used, such as 0.01, 0.05, 0.1 and 0.2 ppm with three replicates for each. After 48 hours of treatment, 0.01 and 0.05 ppm failed to control Argulus sp. infection as the fishes were reared for 14 days after the treatment. 100% mortality of Argulus sp. was achieved with 0.1 ppm with a minimum deleterious effect on the fishes. Treatment with 0.2 ppm showed abnormal behavior resulting in death. Key words: Goldfish, Argulus sp., treatment, sumithion. INTRODUCTION Recently, Argulosis is observed in ornamental fishes, mainly in goldfishes, which are devaluating them as Argulus sp. causing hemorrhages, lesions and erosions on the skin making them unappealing and ultimately causing loss to the aquarium fish traders. The parasites feed by piercing the skin of their host, injecting a toxin and drawing off blood (Shimura and Inoue 1984). It is believed that the toxic substances released by the parasite during feeding are responsible for severe reaction surrounding the area of attachment and subsequent penetration. Describing the pathogenecity of Argulus sp., Hoffman and Meyer (1974) reported that it could kill a larval eel by a single sting by injecting a cytotoxic toxin. Treatments to combat freshwater fish lice include an array of chemicals (Lahav and Sarig 1962, Kabata 1985). Argulus spp. are reported to be controlled by dip treatments with chemicals, such as potassium permanganate, common salt, glacial acetic acid, gammaxene, organophosphates, etc. The works of Khan (1944), Gopalkrishnan (1964), Shoskov and Kolarova (1977), Inoue et al. (1980), Das et al. (1980), Puffer and Beal (1981), Singhal et al. (1986) and Benz et al. (1995) may be mentioned in this regard. In Bangladesh, there is no specific measure tested to control Argulus spp. but some aquarium fish traders are frequently using potassium permanganate on trial and error basis which often *Corresponding author. 1 Department of Environmental Science, State University of Bangladesh, Dhaka.

2 112 Chowdhury et al. leave the fish in critical condition after treatment and long time exposure to KMnO 4 can form manganese protein compound on the skin of the fishes causing brown staining (Kabata 1985), which ultimately devalued the ornamental fishes. The present study attempts to find out an effective and economically feasible treatment with an organophosphate pesticide for the control of argulosis in goldfish. MATERIALS AND METHODS Sumithion 50 EC: Fenitrothion (O,O-dimethyl-O (3-methyl-nitrophenyl) phosphorothioate) was used as the test pesticide. It is an organophosphate contact insecticide and selective acaricide of low ovicidal properties, which act as cholinesterase inhibitor. Sumithion was used because it is an organophosphate, easily available in market, and low cost chemotherapeutants. Besides, its resideual period is 45 days and needs very low dose for treatment purpose, which is very effective against exoparasite. In the present study Sumithion 50 EC was collected from the Shetu Corporation, Dhaka. The experiments were conducted during a period between February and April, Twenty-five goldfishes (Carassius auratus) of 5±0.2 cm length were collected from a local market without any visible infection of Argulus sp. for artificial induced breeding purpose. They were reared in five glass aquaria (each cm) dividing in five groups with dechlorinated water. Aeration was provided with a commercial grade aerator. Water was changed daily before the test. The fishes were fed three times in a day with commercially packed pelleted feed and tubificid worms at the rate of five per cent of their body weight. After six days of rearing in the aquarium, the fishes were found infected with Argulus sp. The reason behind the development of infection of Argulus sp. in goldfish was that the fishes might be infected with larval Argulus sp. or eggs of Argulus sp. were present in the original source of water in which the fishes were reared in shops. Then the fishes infected with matured male and gravid female Argulus sp. were treated with different concentrations of Sumithion, such as 0.01, 0.05, 0.1 and 0.2 ppm. All the experiments were conducted in the laboratory of the Department of Fisheries, University of Dhaka, at room temperature of 30 ± 2 C. The required amount of the liquid pesticide was measured with the help of a micropipette and diluted with distilled water in a glass jar to obtain the desired dose concentration. The test chemical was poured directly into the water of the test aquarium. A pre-test was conducted on trial and error basis to get an idea about the mortality caused by the pesticide. Four concentrations, viz. 0.01, 0.05, 0.1 and 0.2 ppm were made with the pesticide in order to get 100% mortality and to

3 Control of Argulus sp. infestation in goldfish 113 observe any adverse effects on the fishes within minimum time. In each series of test, three replications were used for each dose and a control was maintained for each dose replication. The fishes were inspected with naked eyes for counting Argulus sp. on the body immediately before treatment. The mortalities of Argulus sp. were counted and the parasites lying on the floor of the aquarium having no movement after probing with a glass rod was counted as dead. The physicochemical variables of the aquarium water were monitored as a precautionary measure to maintain water quality suitable for goldfish and it was done by using HACH s Universal Aquaculture Testing Kit, Model No. FF-2, USA as per instructions directed in the manual. Data analyses were done by using Data Analysis Tools of Microsoft Excel in computer. Observations were made for two weeks after treatment to find out if there was any further infection of Argulus sp. RESULTS AND DISCUSSION The experiments showed that after 48 hours, the doses of 0.01ppm and 0.05 ppm resulted in 43.7 and 60% mortality, respectively, while 0.1 ppm resulted in 100% mortality. Sumithion dose concentration of 0.2 ppm resulted in 100% mortality after six hours, but the fishes showed abnormal behavior like erratic swimming, increased operculum activities, loss of equilibrium and jumping out of test media which arised from the toxic effects of the pesticide. Alam et al. (1995) also observed the same kind of behavioral change with Diazinon in the fry of Cirrhinus mrigala. The experiment with 0.2 ppm concentration was discontinued after eight hours, two out of five fishes were died. Sumithion is an organophosphate pesticide which is a neurotoxin (cholinesterase inhibitor) and for this property it impaired the neural coordination of the fishes resulting in abnormal behavior leading to paralysis and finally death (Prasad and Padmavathi 1998). In the control condition, no mortality was observed. The analysis of variance of the percentage of mortality after 48 hours exposure showed that there were significant differences among the treatments at 5 % level and it was insignificant between the two replications at 1% level. The test animals were reared for two weeks and found that the 0.01 and 0.05 ppm Sumithion treated fishes became infected within 10 days while in the 0.1 ppm Sumithion treated fishes no infection was observed. This phenomenon explained by Prasad and Padmavathi (1998) was due to the fact that Sumithion has low ovicidal action which might fail to destroy the eggs laid by the female Argulus sp. during the experimental period. Also, Sumithion has low chemical stability and hydrolysed at the water temperature of 25 to 35 0 C (Metelev et al.

4 114 Chowdhury et al. 1983). So, the low concentration of Sumithion might be hydrolysed in the aquarium water in the favourable water temperature during the Table 1. The mortality of Argulus sp. on exposure to various concentrations of Sumithion (n = 80). Sumithion conc. (ppm) Dose Time for mortality (h) Argulus sp. No. dead (n) % mortality Control experimental period. Therefore, 0.1 ppm of Sumithion was found effective in controlling Argulus sp. infection within minimum exposure time and without any harmful effects on the goldfish. LITERATURE CITED ALAM, M. G. M., AL-ARABI, S. A. M., HALDER, G. C. and MAZID, M.A Toxicity of Diazinon to the fry of Indian major carp Cirrina mrigala (Hamilton). Bangladesh J.Zool. 23(2): BENZ, W. G., OTTING, L. R. and CASE, A Redescription of Argulus melanostictus (Branchiura:Argulidae), A parasite of California Grunion (Leuresthes tenuis: Athernidae), with notes regarding chemical control of Argulus melanostictus in a captive population. J. Parasitol. 81(5): DAS, P., KUMAR, D., GHOSH, A. K., CHAKRABORTY, D. P. and BHAUMIK, U High yield of Indian major carps against encountered hazards in a demonstration pond. J. Inland. Fish. Soc. 12: GOPALKRISHNAN, V Recent developments in the prevention and control of parasites of fishes cultured in Indian waters. Proc. zool. Soc. Calcutta 17: HOFFMAN, G. L. and MEYER, F. P Parasites of freshwater fishes. T.F.H. Publications, Neptune City, New Jersey. pp INOUE, K., SHIMURA, S., SAITO, M. and NISHIMURA, K The use of trichlorofon in the control of Argulus coregoni. Fish Pathol. 15(1):

5 Control of Argulus sp. infestation in goldfish 115 KABATA, Z., 1985.Parasites and diseases of fish cultured in the tropics. Taylor and Francis, London and Philadelphia. xi+318pp. KHAN, H Study in diseases of fish infestation with leeches and fish lice. Proc. Indian Acad. Sci. 19: LAHAV, M. M. and SARIG, S Development of resistance to Lindane in Argulus populations of fishponds, Bamidesh. 14: METELEV, V. V., KANAEV, A. I. and DZASOKHOVA, N. G Water toxicology. Amerind Publishing Co. Pvt. Ltd., New Delhi., pp.216. PRASAD, D. M. K. and PADMAVATHI, P An effective and economically feasible treatment of organophosphate pesticide and common salt to eradicate the fish ectoparasite, Argulus japonicus Thiele in carp culture ponds. J. Environ. Biol. 19(3): PUFFER, W. H. and BEAL, L. M Control of parasitic infestation in Killifish (Fundulus parvipinnis), Lab. Ani. Sci. 31(2): SHIMURA, S. and INOUE, K Toxic effects of extract from the mouth- parts of Argulus coregoni Thorell (Crustacea: Branchiura). Bull. Jap. Soc. of Sci. Fish. 50(4): 729. SHOSKOV, D. and KOLAROVA, V Study on the action of neguvon and chlorophos against Argulus foliaceus and Dactylogyrus extensus in carps. Veter. Sci. 14(8): SINGAHL, R.N., SWARN, J. and DAVIES, W.R Chemotherapy of six ectoparasitic diseases of cultured fish, Aquaculture 54: