Proliferation and anatoxin production of benthic cyanobacteria associated with canine mortalities along a stream-lake continuum

Lindsay H Johnston; Yannan Huang; Tessa D Bermarija; Cheryl Rafuse; Lydia Zamlynny; Meghann R Bruce; Catherine Graham; André M Comeau; Cecilio Valadez-Cano; Janice E Lawrence; Daniel G Beach; Rob C Jamieson

doi:10.1016/j.scitotenv.2024.170476

Proliferation and anatoxin production of benthic cyanobacteria associated with canine mortalities along a stream-lake continuum

Sci Total Environ. 2024 Mar 20:917:170476. doi: 10.1016/j.scitotenv.2024.170476. Epub 2024 Jan 28.

Affiliations

¹ Centre for Water Resources Studies, Department of Civil & Resource Engineering, Dalhousie University, 1360 Barrington Street, Halifax, NS, Canada.
² Biotoxin Metrology, National Research Council Canada, 1411 Oxford St, Halifax, NS, Canada.
³ Canadian Rivers Institute, Department of Biology, University of New Brunswick, P.O. Box 4400, Fredericton, NB, Canada.
⁴ Nova Scotia Department of Agriculture, Animal Health Laboratory, 65 River Rd, Bible Hill, NS, Canada.
⁵ Integrated Microbiome Resource (IMR), Dalhousie University, Halifax, Canada.
⁶ Biology Department, University of New Brunswick, Fredericton, New Brunswick, Canada.
⁷ Centre for Water Resources Studies, Department of Civil & Resource Engineering, Dalhousie University, 1360 Barrington Street, Halifax, NS, Canada; Biotoxin Metrology, National Research Council Canada, 1411 Oxford St, Halifax, NS, Canada.
⁸ Centre for Water Resources Studies, Department of Civil & Resource Engineering, Dalhousie University, 1360 Barrington Street, Halifax, NS, Canada. Electronic address: jamiesrc@dal.ca.

PMID: 38290679
DOI: 10.1016/j.scitotenv.2024.170476

Abstract

Proliferations of benthic cyanobacteria are increasingly in the public eye, with rising animal deaths associated with benthic rather than planktonic blooms. In early June 2021, two dogs died after consuming material on the shore of Shubenacadie Grand Lake, Nova Scotia. Preliminary investigations indicated anatoxins produced by benthic cyanobacterial mats were responsible for the deaths. In this study, we monitored the growth of a toxic benthic cyanobacterial species (Microcoleus sp.) along a stream-lake continuum where the canine poisonings occurred. We found that the species was able to proliferate in both lentic and lotic environments, but temporal growth dynamics and the predominant sub-species were influenced by habitat type, and differed with hydrodynamic setting, nutrient and sunlight availability. Toxin concentration was greatest in cyanobacterial mats growing in the oligotrophic lakeshore environment (maximum measured total anatoxins (ATXs) >20 mg·kg^-1 wet weight). This corresponded with a shift in the profile of ATX analogues, which also indicated changing sub-species dominance along the stream-lake transition.

Keywords: Anatoxins; Benthic; Lentic; Lotic; cyanobacteria.

MeSH terms

Animals
Bacterial Toxins* / toxicity
Cell Proliferation
Cyanobacteria Toxins*
Cyanobacteria*
Dogs
Lakes / microbiology
Rivers / microbiology
Tropanes*

Substances

Bacterial Toxins
anatoxin a
Cyanobacteria Toxins
Tropanes