In vivo efficacy of lasalocid and pyrimethamine treatments against Anophryoides haemophila, a ciliate pathogen of American lobster Homarus americanus

Published: Dec 19, 2017
Anophryoides haemophila American lobster Homarus americanus Scuticociliatida lasalocid pyrimethamine chemotherapeutants in vivo experiments.

Lasalocid and pyrimethamine was administered to American lobsters infected with A. haemophila. Lasalocid was found to be toxic and acute mortality was observed, when administered in vivo in both infected and uninfected lobsters. Pyrimethamine was found very efficient to treat these ciliates at repeated doses. The mortality was very low and the mean haemocyte counts remained higher than the uninfected control group. The drug seems to delay the appearance of the ciliates in the haemolymph and to lower the spread of these parasites in the epipodite and the hepatopancreas. In uninfected animals treated with this drug, haemocyte counts were similar to uninfected control group. Furthermore, no pathology was observed, when the drug was administered to uninfected lobsters. Since there is no effective treatment for the control of bumper car disease, on the basis of the results of the present study, we suggest that pyrimethamine is a good drug for the treatment of A. haemoplila infection in lobsters.

Article Details
  • Section
  • Research Articles
Download data is not yet available.
Bower, SM, McGladdery SE & Price IM (1994). Synopsis of infectious diseases and parasites of commercially exploited shellfish. Ann. Rev. Fish Dis. 4:1-199.
Cawthorn RJ (1997). Overview of the "bumper car" disease- impact on the North American lobster industry. Int. J. Parasitol. 27:167-172.
Cornick JW & Stewart JE (1968). Interaction of the pathogen Gaffkya homari with natural defense mechanisms oîHomarus americanus. J.Fish. Res.Brd.Can. 25: 695-709.
Cribb AE, Despres Β & Cawthorn RJ (1999). Tetrazolium- based cytotoxicity assay to determine anti-protozoal activity against the scuticociliateA haemophila. Dis. Aquat. Org. 35:213-219.
McDowell EM & Trump BF (1976). Histologic fixatives suitable for diagnostic light and electron microscopy. Arch. Pathol. Lab. Med. 1QQ; 405-414.
Messick GA & Small EB (1996). Mesanophrys chesapeakensis sp.,an histophagous ciliate in the blue crab, Callinectes sapidus, and associated histopathology. Invertebrate Biology 115:1-12.
Morado JF & Small EB (1995). Ciliate parasites and related diseases of Crustacea: A review. Rev. Fisheries Sci. 3: 275-354.
Nothorny MJ, Cawthorn RJ & Despres Β (1996). In vitro effects of chemotherapeutants on the lobster parasite A haemophila. Dis. Aquat. Org. 24:233-237.
Ragan MA, Cawthorn RJ., Despres B, Murphy CA, Singh R, Loughlin B, Bayer RB (1996). The lobster parasite Anophryoides haemophila (Scuticociliata: Orchitophtyidae): nuclear 18S Rdna sequence, phylogeny and detection using oligonucleotide primers. J. Euk. Microbiol 43(4), 341-346.
Speare DJ, Daley J, Markham RJF, Sheppard J, Beaman HJ, Sanchez GJ (1998). Lorna salmonae- associated growth rate suppression in rainbow trout (Onchorynchus truttae) occurs during early- onset xenoma dissolution as determined by in situ hybridization and immunohistochemistry. J. Fish Pis. 21: 345-354.
Speare DJ, Cawthorn RJ, Horney BS, Mac Millan R & MacKenzie AL (1996). Effects of formalin, chloramine Τ and low salinity dip on the behaviour and haemolymplh biochemistry of the American lobster. Can. Vet. J. 37:729-734.
Most read articles by the same author(s)