An essential oil extracted from the Australian tea tree has been shown in a new experiment to have a parasiticidal effect.
A group of experts from the School of Biological Sciences at the University of Bristol have just reported the results of a study which examined the effects of tea tree oil (TTA) upon Sticklebacks infected with the skin fluke Gyrodactylus.
Their findings, which are reported in the journal Diseases of Aquatic Organisms, suggest that tea tree oil can reduce the level of Gyrodactylus and reduce parasite burden on naturally infected fish.
The tea tree oil was mixed with an emulsifier called Tween 80 (0.01%) and dosed at concentrations ranging from 3 to 30 ppmv (parts per million by volume).
"Tea tree oil can reduce the level of Gyrodactylus and reduce parasite burden..."
All doses had some effect, and Tween 80 on its own had the ability to kill some Gyrodactylus parasites. The effect was greatest when the tea tree oil and Tween 80 were used together.
An extract from the Australian tea tree, Melaleuca alternifolia, is already present in some aquarium medications aimed at tackling fungal or bacterial infections, such as API's Melafix.
For further information on the new research see: Steverding D, Morgan E, Tkaczynski P, Walder F, Tinsley R. (2005) - Effect of Australian tea tree oil on Gyrodactylus spp. infection of the three-spined stickleback Gasterosteus aculeatus. Dis Aquat Organ. 2005 Aug 9;66(1):29-32.