Individual study: Skin bacteria that inhibit the chytrid fungus can be added to skins of red-backed salamanders resulting in reduced severity of the disease
Harris R.N., Lauer A., Simon M.A., Banning J.L. & Alford R.A. (2009) Addition of antifungal skin bacteria to salamanders ameliorates the effects of chytridiomycosis. Diseases of Aquatic Organisms, 83, 11–16
This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.
Use antifungal skin bacteria or peptides to reduce chytridiomycosis infection
A randomized, replicated, controlled study in a laboratory in Virginia, USA (Harris et al. 2009) found that the severity, but not the infection rate, of chytridiomycosis was reduced by adding chytrid-inhibiting skin bacteria to the skin of red-backed salamanders Plethodon cinereus. Infection rate did not differ significantly between those with added bacteria (Pseudomonas reactans; 80%) and those with chytrid alone (60%). Numbers of zoospore equivalents on infected individuals were also similar (with bacteria: 6; chytrid alone: 10). However, by day 46, salamanders with the bacteria had lost significantly less body mass (15%) than those with chytrid alone (30%) and a similar amount to controls (bacteria or medium alone: 8%). Following inoculation with skin bacteria, 89% of 18 individuals tested positive for the bacteria. Individuals were randomly assigned to one of four exposure treatments: anti-chytrid skin bacteria, chytrid zoospores, bacteria followed by chytrid zoospores three days later or solution alone. Sample sizes were 5, 20, 20 and 5 respectively. Individuals were tested for chytrid on day 1 and 14 and for skin bacteria on day 1 and 10. Salamanders were bathed with 5 ml of solution containing bacteria (3 x 109 cells/ml) for two hours and/or a solution with chytrid (3 x 106 zoospores/5 ml) for 24 hours.