Egy. J. aquac., Vol. 4, No. (2):1-12 (2014) ISSN: 2090-7877 Causes of mortality in Discus fish (Symphysodon) and trials for treatment Nadia A. Abd El-Ghany, Nahla R. El-khatib, and Soad S. A. Salama Fish Diseases Department- Animal Health Research Institute, Dokki, Giza. Abstract Discus (Symphysodon) from the family cihildae is one of the most popular and expensive aquarium fish. In the past few years, farming of this fish has been well developed in Egypt. In this study, a total number of 30 Symphysodon spp collected randomly from private freshwater ornamental fish farm in Kalubia Governorate at December 2013. Discus fish suffered from mortality after the onset of anorexia, eye cloudiness, ascites, excessive body mucus, frayed dorsal fin and tail rot. They were subjected to clinical, postmortem, parasitic, bacterial and mycotic examinations to clarify the causative agents of mortality. The recovered fungi were Fusarium solani, F. oxysporum and F. moniliform with the prevalence of 50, 33.34 and 16.66% respectively. Bacteriological examination revealed that isolation of Aeromonas hydrophila with prevalence 60% and it was sensitive to Ciprofloxacin. The parasitic examination revealed that fish were infested with Spironucleus spp with prevalence of 80%. The Symphysodon spp which were concomitantly mixed infected by bacterial (A. hydrophila), fungal (Fusarium) and parasite (Spironucleus) were subjected to trials for treatment either by chemical or physical. Key words: Discus fish, Fusarium spp, Aeromonas hydrophila, Symphysodon spp, Spironucleus spp, treatment. Introduction Ornamental fish keeping has become an ever more common hobby global. Several species of ornamental fishes are imported from Southeast Asian countries into other countries (Iqbal et al., 2012). Discus is one of the most popular and expensive aquarium fish and considered as a difficult-to-culture species due to its complex reproductive behavior, involving parental care of eggs and newly hatched larvae (Chelappa et al., 2005 and Manochehr et al., 2014) Infectious diseases pose a constant and serious threat to ornamental fish that are farmed intensively under conditions of high stocking density, poor water quality and poor management. At present, various diseases have been reported in ornamental fish including bacterial diseases (Pate et al., 2005), viral diseases (Hedrick and McDowell, 1995) and parasitic diseases (Leibowitz and Zilberg, 2009 and Smith and Roberts, 2010). Discus fish require higher water temperatures than most other tropical aquarium fish, so they should be maintained between 28ºC – 31ºC Giovanetti and Lucanus (2001). Temperature lower than 27ºC caused Discus became significantly more susceptible to diseases. In Egypt, There are few studies on diseases of discus and causes mortality. 1 Causes of mortality in Discus fish (Symphysodon) and trials for treatment The objective of this study was to survey the causes of loss of such fish in propagation farm, trails for treatment and management control. Materials and Methods Naturally infected Fish A total number of 30 Symphysodon spp of range body weight (0.5 - 3 g) suffered from skin lesions and anorexia. They were randomly collected from private freshwater ornamental fish farm in Kalubia Governorate (complained from Discus mortality) at December 2013 and transported alive to Fish Diseases research department Lab Animal Health Research Institute. Fish hold in fully prepared aquaria for observation and examination as soon as possible in same farm water. Clinical and postmortem examinations All of the collected fish were subjected to clinical signs and postmortem findings according to (Plumb and Bowser, 1983). Mycological examination The mycological methods used in this investigation were described by Chinain and Vey (1988). Tissue specimens measuring approximately 5-10 mm were taken under aseptic precautions from liver, spleen, kidney, gills and skin and inoculated into plates containing Sabouraud's dextrose agar medium with 500 units' penicillin and 2 mg streptomycin per ml-1 to prevent bacterial growth according to (Benk and Rogers, 1970). Cultures were kept at 25oC for 1-4 days. Pure cultures were established using single spore isolation method a small part of fungal mycelium from the 1-4 days culture was transferred using sterile medical needle and inoculated on PDA 2 (Potato Dextrose Agar, (Booth, 1971)). Cultures were incubated at 25oC for 3-7 days. Post inoculation, the spores were stained with lactophenol cotton blue and examined microscopically. A morphometric identification of the fungal isolates was carried out based on culture characteristics, namely colony colour, type of mycelium, shape and septation of micro and macroconidia (Burgess, 1981). Bacteriological examination Samples from liver, spleen, kidney, gills, ascetic fluid and gas bladder of examined Symphysodon spp were streaked onto nutrient agar, trypticase soy agar, Rimler- Shotts medium (RS) and thiosulphate citrate bile salt agar (TCBS) plates then incubated at 25ºC for 24-48 hrs. The growing colonies were picked up in pure form and reinoculated into trypticase soy agar for further identification. Isolates were identified by cultural, morphological and biochemical characterization according to Austin and Austin (2007) and through using commercial miniaturized API®20E system (Biomerieux, France) according to manufacturer’s instructions. Antibiogram It was carried out using various chemotherapeutic agents against the isolated A. hydrophila and judgment of the obtained results in comparison to interpretive standards was applied as described by (Quinn et al., 2002). Parasitological examination Fish were examined externally and internally for gross signs of parasitism and any abnormalities. Smears made from skin lesions and from various sites along the gastrointestinal tract and of the blood, and imprints made of internal Nadia et al., organs (liver, kidney, spleen, and gall bladder). Microscopic examination of wet mounts under bright field and phase contrast X40. Stained smears with Giemsa stain were used in detailed examination and identification according to (Kent et al., 1992 and Buchmann and Uldal, 1996). Treatment experiment A total number of 60 natural infected Symphysodon spp. with mixed bacterial, mycotic and parasitic infection were divided into 6 groups, ten fish each. The fish were holding in six full glass aquaria 40×40×50 cm with Chlorine free tap water. Fish starved two days before treatment according to (Innes, 1966). All fish were observed over two weeks period for morbidity and mortalities and examined 24 hours after the end of the treatment. A treatment was considered effective when it caused a complete removal of infection of all fish used in the assay (Tojo and Santamarina, 1998). Chemical treatment The natural mixed infected Symphysodon spp. in group one were treated by exposed long bath treatment of Metronidazole 5ppm for 12 hour for three times day after day and 50% water changes before drug administration. The fish in group two were exposed to commercial antibiotics ciprofloxacin (5ppm for 5 days and 50% water changes before drug administration). The choice of these drugs was according to sensitivity test result and the doses according to (Noga, 2010). All chemical treatments were applied at water temperature of 20°C and dissolved oxygen was censured by regular aeration. Physical treatment In this type of treatment, there were two aquaria ( group three and group four) contain natural mixed infected Discus fish held at 25°C and 30°C using thermostatically control water heaters. Control infected Discus fish groups were subjected to similar circumstances, but without use of any chemicals. Results Clinical signs Naturally infected Symphysodon spp showed ulceration on the skin especially on the head and dorsal fins. Fish suffered from exophthalmia, eye cloudiness, congested gills abdominal distention, excessive body mucus, frayed dorsal fin and tail rot Fig .1 (A, B & C). Post- mortem findings Postmortem findings of naturally infected fish revealed congestion of visceral organs, in some cases paleness and focal liver with yellowish nodules, enlargement of spleen, yellowish fluid in abdominal cavity. The intestine showed yellowish mucus and haemorrhages of gas bladder. In some cases gas bladder filled with yellowish fluid Fig .1 (D). Fungal study The recovered fungi isolated on Sabouraud's dextrose agar medium and preliminarily identified on PDA were identified morphometrically as members of the genus Fusarium, namely Fusarium solani (50%), F. oxysporum (33.34%) and F. moniliform (16.66%). The prevalence of recovery of such Fusarium species in infected ornamental fish Symphysodon spp reached (100%) (Table, 1). Morphological criteria of Fusarium species were summarized Fusarium solani: colony grow rapidly on PDA with dense aerial white to 3 Causes of mortality in Discus fish (Symphysodon) and trials for treatment cream mycelium in concentric rings, abundant, floccose, somewhat powdery in aged cultures which reverse to brownish colour, showing average growth rate per day at 25oC Fig. 2 (B). Microconidia usually abundant, ellipsoidal, fusiform or kidney shaped after 2-3 days in fresh isolates. Macroconidia were abundantly developed after 4-7 days with thick walled having 3 to 4 septa, straight, parallel sided for most of length. The apical cell blunt had rounded end Fig. 2 (C & D). Fusarium oxysporum: colonies are dense and floccose, white mauve mycelium, which reverse dark brown. Microconidia were long produced in false heads, carried by short conidiophores and consisted of one or two cells, chlamydospores with a thick wall, produced singly or in pairs. Macroconidia only slightly curved, usually with 3 septa, occasionally more, thin walled with a notched or foot-shaped basal cell and short. Fusarium moniliform: colonies are dark violet with dense aerial mycelium which is delicately floccose to felt. Microconidia were formed in chain, fusiform to clavate with a slightly flattened base, they occasionally become one septate. Macroconidia are inequilaterally fusoid, delicate, thin walled, often sharply curved apical cell and pedicel at basal cell, they are 3-7 septate. Bacteriological study Bacteriological examination of liver, spleen, kidney, gills, ascetic fluid and gas bladder of examined fish revealed that 72 bacterial isolates were recovered and characterized from 18 infected fish and the total prevalence of bacterial Infection was 60% (Table, 1). Phenotypic 4 characteristic of bacterial isolates are summarized in (Table 2) and showed that the isolates were identified as A. hydrophila. In-vitro sensitivity tests of isolated bacterial strain A. hydrophila to different chemotherapeutic agents revealed that the isolates were sensitive to Ciprofloxacin. Parasitological study There were no ectoparasites detected and only diplomonad flagellates Spironucleus spp in intestine, liver, gall bladder, spleen, heart, skin and fins was observed under a light microscope and phase contrast X40. The intensity revealed that higher occurrence in the hind part of the intestine than internal organs. The prevalence of parasitic infestation in Symphysodon spp was 80% (Table, 1). The morphological characteristics of diplomonad flagellates under light microscopes indicated that the parasite was Spironucleus Spp. The morphology of the (n= 20 ) trophozoite stages have transparent elongated pyriform body and consider smallest diplomonad flagellates, with a body range of 13- 20 mm long and 5.510.4 mm wide. The parasite is anterior tapering and intertwined elongate compact nuclei S-shaped and wrap around each other at their narrow anterior ends. The body is emerging three anterior flagella, and one posterior flagellum (Fig. 2 (A)). Treatment trials In the present investigation, the trials to treat natural mixed infected Symphysodon spp. either chemical or physical. Table (3) shows that all mixed infected fish in group one which were treated with chemical and physical management (Metronidazole 5ppm for 12 Nadia et al., hour for three times, day after day and 50% water changes before drug administration) have recovered from infection within 2 weeks post treatment with complete disappearance of clinical signs meanwhile all mixed infected fish in group two which were treated with ciprofloxacin (5ppm for 5 days and 50% water changes before drug administration) have not completely recovered from infection, and two weeks post treatment morbidity rate was 50% of fish . management in the form of increase of water temperature to 30°C were recovered from infection within two week post exposure but 25°C not completely eradicated infection, however there was some fish loss in compared with chemical treatment by Metronidazole include physical management in the form of partial (50%) water changes. On the other hand, all of control mixed infected fish in group three and six were dead. Table (4) shows that all mixed infected fish that exposed to physical Fig. (1): show naturally infected Symphysodon spp suffering from ulceration on the skin especially on the head, dorsal fins, tail rot and ascites. Arrow (A, B & C) show severe congestion of internal organs. Arrow (D). 5 Causes of mortality in Discus fish (Symphysodon) and trials for treatment Fig.2. show Giemsa stained Spironucleus isolated from Symphysodon spp. X100, arrow(A). Colonies of Fusarium solani on PDA showing aerial, white to cream mycelium in concentric rings (B). Microconidia of Fusarium solani after 2-3 days stained with lactophenol cotton blue showing fusiform shape. (X40) arrow(C). Macroconidia of Fusarium solani showing slightly curved, more and thin walled (X 40) arrow (D). Table (1): The Prevalence of natural mixed infection of examined Symhysodon spp. Types of infections Fungal infection Fusarium sp. Parasitic infection Spironucleus Bacterial infection A. hydrophila 6 No. of examined Fish 30 No. of naturally infected Symhysodon spp % 30 100 24 80 18 60 Nadia et al., Table (2): Morphochemical characteristics of bacterial isolates from Symhysodon spp. Morpho-chemical tests Motility Growth on R.S Growth on MacConkey`s + + Morpho-chemical tests Indole Gelatin liquefaction - Gas from glucose - + Ferementation of glucose – + - Esculin hydrolyze Gram stain Swarming - - H2S - - Nitrate reduction - + Urease - Assimilation of : Mannitol Maltose Rhmnose - A. hydrophila Cytochrome Oxidase Citrate Growth at: 4°C Growth at: 41°C Fluorescent Pigments Arginine Dihydrolase Catalase Assimilation of : Sucrose Sorbitol Glucose Arabinose + - A. hydrophila. + + -: mean negative results, +: mean positive results Table (3). The cumulative mortality rate and the morbidity rate of treated Symhysodon spp by chemicals treatment. Time in weeks 0 1 2 Control Cumulative Mortality % 0 50 100 Morbidity % 100 50 0 Metronidazole Cumulative Morbidity Mortality % % 0 100 10 20 10 0 Ciprofloxacin Cumulative Morbidity Mortality % % 0 100 20 60 30 50 7 Causes of mortality in Discus fish (Symphysodon) and trials for treatment Table (4). Cumulative mortality and morbidity rates of treated Symhysodon spp by physical treatment (heat) Control Water temperature Water temperature 20ºC 25ºC 30ºC Time in Cumulative Cumulative Cumulative Morbidity Morbidity Morbidity Mortality Mortality weeks Mortality % % % % % % 0 100 0 100 0 100 0 50 50 10 80 0 20 1 100 0 30 50 0 0 2 N.B.: The number of fish in each group is 10 fish Discussion Ornamental fish keeping has become an ever more common hobby global. Discus is one of the most popular and expensive aquarium fish and considered as a difficult-to-culture species. Studies on diseases of ornamental fishes especially Discus in Egypt is few. Studies on external parasites of ornamental fishes were done more frequently than the ones on internal parasites. In the present study, causes of mortality among Discus (Symphysodon spp) fish were investigated at late winter of 2013. Naturally infected Symphysodon spp showed ulceration on the skin especially on the head and dorsal fins. Fish suffered from exophthalmia, eye cloudiness, ascites, excessive body mucus, frayed dorsal fin and tail rot. These results were in agreement with Paull and Matthews (2001) who showed that the infected cichlids with Spironucleus vortens, showed varied clinical signs from external to severe systemic symptoms and disagreed with Kulda and Lom, (1964) showed that infected angelfish had no signs of the disease although they were infected by Spironucleus elegans. Also, Roberts et al. (2009) found that the most common clinical signs of motile aeromonads that 8 affect fish are ulcerative skin lesion, lethargy, abdominal distension, ascites and anorexia. Regarding the causative agents of mortalities among Symphysodon was the mixed infection with A. hydrophila in prevailing of 60%, Spironucleus spp 80% and Fusarium spp 100%. These results are consistent with those obtained by (Pate et al., 2005 and Smith and Roberts, 2010). Several cases of infection related to Fusarium spp. have been reported in ornamental fishes farm (Manochehr et al., 2014). Species of Fusarium responsible for the disease in ornamental fishes have been identified F. solani and F. moniliform (Iqbal and Ramsha, 2013). F. oxysporum causes several plant diseases Burgess (1981) and a gill disease in the crayfish (Maestracci, 1987). The fungus species is thus found in plants and in different species of freshwater and marine crustaceans. Fungal identification was based on the presence of fungal hyphae and conidia by using light microscopy. Hyphae of F. solani appear septated and the characteristic canoe-shaped macroconidia. These results agreed with previously described (Lightner, 1996). Nadia et al., Also, the morphological culture and biochemical character of isolated A. hydrophila was similar to recorded by (Awad, 2011). Control of fish disease is currently based almost entirely on chemotherapy and it will entirely retain a role in the management of fish culture systems (Roberts, 1995). Regarding to the sensitivity of A. hydrophila to different antimicrobials, the present study showed that Ciprofloxacin was the drug of choice. Similar results were recorded by Musa et al. (2008) and Awad (2011) who mentioned that Ciprofloxacin has proved a world-wide efficacy to control or treat bacterial infections in fish. Successful control of bacterial diseases of cultured fish is a major management and economic problems for the aquaculture industry (Plumb, 1999). The results of the treatment indicated that chemical treatment with Metronidazole included physical management of partial water changes was effective to overcome parasitic and bacterial infection and absence of morbidity and mortalities after two weeks. These results agreed with Gratzek, (1983) and Woo (2006) who mentioned that Metronidazole is an antiprotozoal medication used in fish, although Sangmaneedet and Smith (1999) found that combination of metronidazole and Magnesium sulfate have been the most effective chemotherapeutic agents in inhibiting the growth of S. vortens in angelfish but the physical management of change water may help for removing such parasite before infecting another fish. In the present study, physical management in the form of increase of water temperature to 30°C showed no mortality and overcome all infections but at 25ºC not completely disappeared of morbidity and mortality rate. These results are consistent with those obtained by Sung and Cook (1981) for increasing temperatures in the range of 15-35°C decrease the potential for growth Fusarium spp. and Kersters et al. (1995) who investigated the incidence of Aeromonas hydrophila is found in high numbers when the temperature was around 20–25 ºC and were rarely detected during cold seasons. Also obtained results supported those reported by Bassleer (1983) and Buchmann and Uldal (1996) who found the completion of Hexamitid growth was at temperature15ºC-20ºC and the optimal performance at 10ºC . Gratzek (1983) and Sangrnaneedet and Smith (1999) who reported that the rise in water temperature up to 28ºC-29ºC enhance the fish’s immune response to overcome diseases occurrence. In conclusion, the causative agents of Discus mortalities were concurrent parasitic / bacterial and fungal infections. This circumstance was the real scenarios for infections in the fish environments where water is naturally inhabited by the ubiquitous bacteria, fungal and parasites and any stress factors causing fish diseases. In case of rearing tropical fish (Discus) we need to take into our consideration the special nature of such fish. So physical management and chemical treatment should be applied if disease establish. References Awad, S.M. (2011). Studies on prevailing bacterial diseases in carp. Ph.D.. Fish Diseases and Management Dept., Fac. Of Veterinary Medicine, Suez Canal University. Austin, B. and Austin, D.A. (2007). Bacterial Fish Pathogens: Diseases in 9 Causes of mortality in Discus fish (Symphysodon) and trials for treatment farmed and wild fish. 4th ed. Praxis Publishing Ltd, Chichester, UK, Printed in Germany. Bassleer, G. (1983). Disease prevention and control Spironucleus/Hexamita infection, holein the-head disease. Freshwater Marine Aquarium.6,38-60. Benk, E.S. and Rogers, L.L (1970). Medical mycology manual Burgess Publishing Company 3rd edition. Booth C. (1971). The Genus Fusarium ,pp.94-97.Common-wealth Mycological Institute, Kew, U K. Buchmann K and Uldal A (1996). Temperature, pH and bile dependent in vitro cultivation of Hexamita salmonis from rainbow trout Oncorhynchus mykiss intestine. Dis Aquat Org 24:169–172. Burgess, L.w. (1981). General ecology of the fusaria .In: Nelson, P. E., Toussoum, T. A., Cook, R. J. (Eds.), Fusarium: Diseases, Biology and Taxonomy. Pennsylvania State University Press, University Park, pp. 225-235. Chelappa, S., Camara, M.R. and Verani, J. (2005). Ovarian development in the Amazonian red discus, Symphysodon discus Heckel (Osteichthyes: Cichlidae). Brazilian Journal of Biology 65: 609- 616. Chinain, M. and Vey, A. (1988). Experimental study of Fusarium solani infection in Astacus leptodactylus and Pacifastacus leniusculus (Crustacea Decapoda). Dis. Aquat. Org., 5: 215-223. Giovanetti T.A. and Lucanus O. (2001). Discus Fish, A Complete Pet Owner’s Manual. Barron’s Educational Series, Barron’s Publ. Inc., Hauppauge, NY. Gratzek, JB. (1983). Control and therapy of fish diseases. Adv Vet Sci Comp Med. 27:297-324. 10 Hedrick, R.P. and McDowell, T.S. (1995). Properties of iridoviruses from ornamental fish. Veterinary Reseach. 26, 243-247. Innes, W. T. (1966). Exotic Aquarium fishes 19th Ed., Aquarium in Corporate New Jersy, 7 (12) (24-25): 29-30. Iqbal, Z and Ramsha, S. (2013). Some pathogenic fungi parasitizing two exotic tropical ornamental fishes. Int. J. Agric. Biol., 15: 595 – 598. Iqbal, Z, Sheikh, U and Mughal, R (2012). Fungal infections in some economically important freshwater fishes. Pak Vet J, 32 (3): 422-426. Kent, M.L., Ellis, J., Fournie, J.W., Dawe, S.C., Bagshaw, J.W. and Whitaker, D.J. (1992). Systemic hexamitid (protozoa: diplomonadida) infection in seawater pen-reared chinook salmon Oncorhynchus tshawytscha. Dis Aquat Org., 14:81-89. Kersters, I., Huys, G., Van Duffel, H., Vancanneyt, M., Kersters, K.and Verstraete, W. (1995). Survival potential of Aeromonas hydrophila in freshwaters and nutrient-poor waters in comparison with other bacteria. J Appl Bacteriol 80, 266–276. Kulda, J. and Lom, J. (1964). Remarks on the diplomastigine flagellates from the intestine of fishes. Parasitology. 54, 753-762. Leibowitz, M.P. and Zilberg, D. (2009). Tetrahymena sp. infection in guppies, Poecilia reticulata Peters: parasite characterization and pathology of infected fish. Journal of Fish Diseases., 32, 845-855. Lightner, D.V. (1996). A Handbook of Shrimp Pathology and Diagnostic Procedures for Diseases of Cultured Penaeid Shrimp. World Aquaculture Society, Baton Rouge, LA., USA. Nadia et al., Maestracci ,V. (1987). Reches sur les infection fongiques des branchies a Fusarium chez les Crustaces Astacus leptodactylus Esch. et Austropotamob ius pallipes Ler. These Doctorat, Academie de Montpellier, France, 238pp. Manochehr, M., Faham, K., Mehdi, R. and Mohammad, R. (2014). Prevalence of Argulus foliaceus and Fungal Infections in Some Ornamental Fishes Discus (Symphysodon discus), Dwarf Gourami (Trichogaster lalius) and Guppy (Poecilia reticulata)] in Isfahan City of Iran. Journal HomePage: http://vetdergi.kafkas.edu.tr online Submission : http :// vet dergikafkas .org DOI: 10.9775 / kvfd .2014.10844. Musa N. Lee Seong W., Shaharom F. and Wendy W. (2008). Surveillance of Bacteria Species in Diseased Freshwater Ornamental Fish from Aquarium Shop. World Applied Sciences Journal 3 (6): 903-905. Noga, E.J. (2010). Fish disease- diagnosis and treatment. 2nd edition. WileyBlackwell, Mosby-yearbook, Inc. watsworth publishing Co., USA. pp.366. Pate, M., Jenčič, V., Dovč, M.Ž. and Ocepek, M. (2005). Detection of mycobacteria in aquarium fish in Slovenia by culture and molecular methods. Diseases of Aquatic Organisms. 64, 29-35. Paull, G.C. and Matthews, R.A. (2001). Spironucleus vortens, a possible cause of hole-in-the-head disease in cichlids. Dis. Aquat Org., 45:197–202. Plumb, J. A. (1999). Health maintenance and principal microbial diseases of cultured fishes. Iowa state Press. U.S.A. Plumb J.A. and Bowser, P.R. (1983). Microbial fish diseases laboratory manual. Auburn University Alabama Agricultural Experiment station, Auburn, Alabama. Quinn, P. T.; Markey, B. K.; Carter, M. E.; Donnelly, W.J. and Leonard,F.C. (2002). Veterinary Microbiology and Microbial disease. First Published Blackwell Science Company, Lowa, State University Press. Roberts, R. J. (1995). Aquatic animal health towards. 2000 In: Diseases in Asian Aquaculture II. Shariff, M., T. R. Arthur, R. P. Subasinghe (eds.). Fish Health Section, Asian Fisheries Society, Manila., pp. 3-7. Roberts H.E, Palmeiro B., and Weber E.S. (2009) Bacterial and Parasitic Diseases of Pet Fish. Vet Clin North Am Exot Anim Pract 12(3):609638. http://www.elsevier.com/copyrig ht Sangrnaneedet S. and Smith S.A., (1999). Efficacy of various chemotherapeutic agents on the growth of Spironucleus vortens, an intestinal parasite of the freshwater angelfish .Dis Aquat Org. Vol. 38: 47-52. Smith, S. A. and Roberts, H. E. (2010). Parasites of fish. In: Fundamentals of Ornamental Fish Health. Roberts H. E. (ed). Hoboken (NJ): Wiley-Blackwell, pp. 102-112. Sung, J. and Cook, R.J. (1981). Effect of water potential on reproduction and spore germination of Fusarium roseum "Graminearum","Culmorum" and "Avenaceum". Phytopathology, 71(5):499-504 Tojo, J.L. and Santamarina, M.T. (1998). Oral pharmacological treatments for parasitic diseases of rainbow trout Oncorhynchus mykiss. I: Hexamita salmonis. Dis Aquat Org., 33:51-56. 11 ‫‪Causes of mortality in Discus fish (Symphysodon) and trials for treatment‬‬ ‫‪Infections,‬‬ ‫‪Metazoan‬‬ ‫‪2nd edition, CABI, U.K.‬‬ ‫‪Woo, P.T.K. (2006). Fish Diseases and‬‬ ‫‪Disorders, Volume 1: Protozoan and‬‬ ‫المل ص العربى‬ ‫أسب‬ ‫الن‬ ‫فى اأسم‬ ‫ال رصي‬ ‫مح ا للعاج‬ ‫ن ي احمد عبد الغنى ‪ -‬ن ل رمز ال طيب سع صبر عبد الحليم‬ ‫قو با أمرا اأسما ‪ -‬مع د با صاة الاي ا – الدق ‪ -‬الجيزم‬ ‫(سنيمى سن ن ) هن ادندم من أسنما الزي نة‬ ‫ا ت ننا‪ ,‬ع ن الو ن اق ال ليلننة الما ننية ت ن ت ن ير‬ ‫تعتبر أسما الدسكس (ال رصية) من ون‬ ‫الجميلننة اأك نر شننعبية لك ننا مكلىننة ع ن‬ ‫استز ا هذ ااسما بشكل جيد ع مصر‪.‬‬ ‫ع هذ الد اسة ت تجمين ندن‪ 03‬سنمكة شن اييا من أسنما الدسنكس (سنيمى سن ن )‬ ‫م مز ة أسما ي ة خاصة عن مااعةنة ال لي بينة عن نيونمبر ‪ 3300‬كاون اأسنما تعناو‬ ‫أمننرا اأسننما ‪ -‬مع نند بان صنناة‬ ‫من ووننبة وىن ة اليننة تن ا سننال ا الن معمننل بان‬ ‫مل عا صاق ميكر بيل جية ىيلية‪.‬‬ ‫الاي ا ت عاص ا عاص ظاهرى عاص تشريا‬ ‫كاو العاماق المر ية ل اأسما قبل ال ىن ة تبندأ بى ندا عن الشن ية‪ ,‬تامنة عن العني ‪,‬‬ ‫ي نانم ع ن كميننة الماننا المج ن للجو ن ‪ ,‬تعى ن ع ن الز ىننة الة ريننة الذيليننة ج ن ن س ن ايل‬ ‫ث ال ى ة‪.‬‬ ‫ا تشادية نم ية ع التج يف الب‬ ‫أ ننا الىا ن ط ال ىيليننة البكتيريننة الى ريننة أ اأسننما المصننابة قنند ت ن ننز م ننا‬ ‫موننبباق مر ننية ميكر بيل جيننة ىيليننة كاونن كنناأت ‪ :‬الى رينناق المعز لننة ت تمنن لى ننر‬ ‫عي ا يننن و سننن او (‪ , )٪ 3‬ع نننر الىي ا يننن و أ كويونننب ي (‪ )٪00.03‬الىي ا يننن و‬ ‫م ويلى ن و ‪ .٪0 .‬كشننف الىاننص البكتري ل ن ج ن ننز تننرم اير م ونناو هينند عيا‬ ‫(‪ )٪ 3‬جد او ا دواسة للويبر عل كواسي ‪ .‬كاو ااصابة ال ىيلية ب ىينل سنبير ويكلس عن‬ ‫اأمعاء اأ اء الداخلية ب وبة (‪.)٪03‬‬ ‫قننند أ نننا الد اسنننة أ ااصنننابة الميكر بينننة كاوننن ماتل نننة ببكتيرينننا (اير م وننناو‬ ‫هينند عيا)‪ ,‬الى رينناق (الىي ا ي ن و) ال ىيلينناق (سننبير ويكلس) قنند ت ن الننتاك ع ن اأصننابة‬ ‫المر ية ب رة العا الماتلىة إما الكيميايية أ استاداو الارا م ‪.‬‬ ‫‪12‬‬