Parasite survey of fathead minnows, golden shiners, and white suckers used as bait in Wisconsin

Abstract

The purpose of this study was to identify and describe parasites species in three Wisconsin baitfish species from five different baitfish sources. Baitfish examined were fathead minnow (Pimephales pramelas), golden shiner (Notemigonus crysoleucas), and white sucker (Catostomus commersoni) from either wild, hatchery, wholesale, import, or retail sources throughout Wisconsin and the North Central Region (NCR). A total of 350 baitfish were sampled from five sources within two states (WI and MN) and at least 20 fish of each baitfish species were necropsied. There was no statistical difference in mean prevalence among baitfish sources for all host species combined and for each of the baitfish species. AN OVA results demonstrated that mean abundance and mean intensities differed significantly among sources for both fathead minnow and white sucker. Two parasite species occurred, Neascus spp. and Ornithodiplostomum ptychocheilus, across all five baitfish sources. Five parasite species were observed within all three baitfish species (Hysteromorpha tri/oba, Myxobolus spp., Neascus spp., Neoechinorhynchus spp. and Spiroxys spp.). From results a list of baitfish parasite species was generated and potential transfer pathways between sources were identified. Natural resource management within the NCR can use the baseline knowledge to possibly generate management strategies (e.g., pathogen screening, baitfish health certificates) aimed at recognizing baitfish/parasite transfer risks or pathogen screening protocol used prior to baitfish transfer.