Fatal Neurotoxicosis in Dogs Associated with Tychoplanktic, Anatoxin-a Producing Tychonema sp. in Mesotrophic Lake Tegel, Berlin

Abstract

In May 2017, at least 12 dogs showed signs of acute neurotoxicosis after swimming in or drinking from Lake Tegel, a mesotrophic lake in Berlin, Germany, and several of the affected dogs died shortly afterwards despite intensive veterinary treatment. Cyanobacterial blooms were not visible at the water surface or the shorelines. However, detached and floating water moss (Fontinalis antipyretica) with high amounts of Tychonema sp., a potential anatoxin-a (ATX) producing cyanobacterium, was found near the beaches where the dogs had been swimming and playing. Necropsies of two of the dogs revealed no specific lesions beside the anamnestic neurotoxicosis. ATX was detected in concentrations up to 8700 µg L−1 in the stomach contents, while other (neuro)toxic substances were not found. In the aqueous fraction of Fontinalis/Tychonema clumps sampled after the casualties, ATX was found in concentrations up to 1870 µg L−1. This is the first report of a dense population of Tychonema sp. in stands of Fontinalis resulting in high ATX contents. This case emphasizes the need for further investigation of potentially toxic, non-bloom forming cyanobacteria in less eutrophic water bodies and underlines the novel challenge of developing appropriate surveillance schemes for respective bathing sites.

Temperature Effects Explain Continental Scale Distribution of Cyanobacterial Toxins

“…Identification of CYN and ATX was performed in the positive MRM mode with the following transitions: CYN m / z 416.1 [M + H] + to 194 (quantifier) and 416.1/176, and ATX m / z 166.1 [M + H] + to 149, 166.1/131, 166.1/91, 166.1/43 (quantifier). Mass spectrometric parameters are given in [ 71 ]. Certified reference standards were purchased from National Research Council (Ottawa, ON, Canada).…”

A European Multi Lake Survey dataset of environmental variables, phytoplankton pigments and cyanotoxins

“…Identification of CYN and ATX was performed in the positive MRM mode with the following transitions: CYN m/z 416.1 [M + H] + to 194 (quantifier) and 416.1/176, and ATX m/z 166.1 [M + H] + to 149, 166.1/131, 166.1/91, 166.1/43 (quantifier). Mass spectrometric settings are given in 36 . Certified reference standards were purchased from National Research Council (Ottawa, ON, Canada).…”

Multi-Toxin Occurrences in Ten French Water Resource Reservoirs

“…The injection volume was 10 μL. Identification and quantification of the MCs ([Asp3]-MC-RR, MC-RR, MC-YR, [Asp3]-MC-LR, MC-LR, MC-LW, MC-LF, MC-LA, standards purchased at Enzo Life Sciences, Lörrach, Germany) was performed in the MRM (Multiple Reaction Monitoring) mode with the transitions given by Fastner et al [ 63 ].…”

“…The mass spectrometer was operated in the multiple reaction-monitoring mode (MRM). For the determination of CYN deoxyCYN, and ATX the transitions given in [ 63 ] were used. Quantitation of CYN, deoxyCYN and ATX was performed with the most intensive transition.…”