With just one cricket, your gecko will probably be able to tolerate any pesticides that may have been on the cricket. However the cricket could give your leo a case of something...parasites. Watch the stoools for signs of runniness, lack of appettite, etc. If symptoms develop, bring a fecal sample to the vet to have a fecal done, you the organism can be identified and hopefully treated.
Tell your son that wild crickets and other insects can carry diseases that can kill the leo or make him very sick, and not to feed him any "found" bugs.
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Sarah Stettler aka Starling
Sarah@stargecko.com
StarGecko.Com COMING SOON! Star Quality Leopard Geckos
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