Fig. 1.

Experimental schematic and timeline. Timeline begins at t_-3 when density of parasites in polychaete cultures (inset a) was estimated in replicate water samples to calculate dose administered on t₀ and t₆. Specific-pathogen-free (SPF) well water (“W”) was used as a negative control and a mock exposure t₀ and t₆ in treatments that received no parasites on those exposure dates “W”- denotes water, “I: denotes genotype-I and “II” denotes genotype-II (inset b). * denote treatments used for cytokine and immunoglobulin assays (b).