Rj. Sandler et al., SEASONAL PREVALENCE OF CLOSTRIDIUM-BOTULINUM TYPE-C IN SEDIMENTS OF ANORTHERN CALIFORNIA WETLAND, Journal of wildlife diseases, 29(4), 1993, pp. 533-539
The prevalence of Clostridium botulinum type C (% of positive sediment
samples) was determined in 10 marshes at Sacramento National Wildlife
Refuge (SNWR), located in the Central Valley of California (USA), whe
re avian botulism epizootics occur regularly. Fifty-two percent of 2,2
00 sediment samples collected over an 18-mo period contained C. botuli
num type C (both neurotoxic and aneurotoxic) which was present through
out the year in all 10 marshes. The prevalence of C. botulinum type C
was similar in marshes with either high or low botulism losses in the
previous 5 yr. Marshes with avian botulism mortality during the study
had similar prevalences as marshes with no mortality. However, the pre
valence of C. botulinum type C was higher in marshes that remained flo
oded all year (permanent) compared with marshes that were drained in t
he spring and reflooded in the fall (seasonal). The prevalence of C. b
otulinum type C declined in seasonal marshes during the dry period. Si
milar declines did not occur in the permanently flooded marshes.