Persistence of Clostridium botulinum neurotoxin type E in tissues from selected freshwater fish species: implications to public health.
Rainbow trout (Oncorhynchus mykiss), round gobies (Neogobius melanostomas), yellow walleye (Stizostedion vitreum), and yellow perch (Perca flavescens) were given Clostridium botulinum neurotoxin type E (BoNT/E) at four doses (0, 800, 1500, and 4000 mouse lethal doses). BoNT/E was sought in the fish tissues at death or at the conclusion of the experiment (10 days after treatment). Fish were divided into a "fillet" (axial musculature) and a "nonfillet" sample before testing for BoNT/E toxicity with a mouse bioassay. BoNT/E was detected in all species. The percentage of positive BoNT samples ranged across the species and doses from 0 (trout, perch, and walleye) to 17% (round goby) in fillet tissues and from 0 (perch) to 92% (round goby) in nonfillet tissues. The lack of positive fillet samples in three key commercial fish species suggests that the public health implications of eating these fish are minimal. However, the presence of toxin in the nonfillet compartment of a high proportion of fish supports the hypothesis that live intoxicated fish are a vehicle for the transfer of BoNT/E to fish-eating birds, which are then in turn, intoxicated.
Yule
Adam M
AM
Aquaculture Centre, Department of Animal and Poultry Science, Ontario Veterinary College, University of Guelph, Guelph, Ontario, Canada.
Austin
John W
JW
Barker
Ian K
IK
Cadieux
Brigitte
B
Moccia
Richard D
RD
D000818:Animals; D001681:Biological Assay; D001905:Botulinum Toxins / Q000633:toxicity*; D047970:Clostridium botulinum type E / Q000254:growth & development / Q000378:metabolism; D003257:Consumer Product Safety; D004305:Dose-Response Relationship, Drug; D005399:Fishes / Q000382:microbiology*; D020387:Food Chain; D005506:Food Contamination / Q000032:analysis*; D005618:Fresh Water; D006801:Humans; D051379:Mice; D011634:Public Health; D013045:Species Specificity
D001905:Botulinum Toxins; C096326:botulinum toxin type E