Cyanobacterial poisoning in livestock, wild mammals and birds – an overview

Abstract

Poisoning of livestock by toxic cyanobacteria was first reported in the 19th century, and throughout the 20th century cyanobacteria-related poisonings of livestock and wildlife in all continents have been described. Some mass mortality events involving unrelated fauna in prehistoric times have also been attributed to cyanotoxin poisoning; if correct, this serves as a reminder that toxic cyanobacteria blooms predate anthropogenic manipulation of the environment, though there is probably general agreement that human intervention has led to increases in the frequency and extent of cyanobacteria blooms. Many of the early reports of cyanobacteria poisoning were anecdotal and circumstantial, albeit with good descriptions of the appearance and behaviour of cyanobacteria blooms that preceded or coincided with illness and death in exposed animals. Early necropsy findings of hepatotoxicity were subsequently confirmed by experimental investigations. More recent reports supplement clinical and post-mortem findings with investigative chemistry techniques to identify cyanotoxins in stomach contents and tissue fluids.

Emerging health issues of cyanobacterial blooms

“…Several poisoning episodes of livestock, wild and domestic animals have been associated with the occurrence of cyanobacterial blooms in surface waters used for drinking [96]. Although anecdotal reports dated many years ago, the issue has been raised as relevant only more recently, when a specific causeeffect relationship could be established, due to appropriate sampling schedules of both water and body fluids and investigative chemistry techniques.…”

Tropical cyanobacterial blooms: a review of prevalence, problem taxa, toxins and influencing environmental factors

“…Currently there are two types of cyanotoxins that are particularly problematic to humans: hepatotoxins (cyclic peptides) and neurotoxins (alkaloids) (Sivonen, 1999;Stewart et al, 2008;Wiegand and Pflugmacher, 2005;Zurawell et al, 2005;Chen et al, 2009). Toxin-producing cyanobacteria have been responsible for serious cases of human and livestock poisoning and deaths in a number of countries worldwide (e.g., in Brazil, Australia and North America) (Francis, 1878;Beasley et al, 1989;Azevedo et al, 2002;Cox et al, 2005;Sotero-Santos et al, 2006).…”

Experimental immunology Assessment of the potential genotoxic and proapoptotic impact of selected cyanotoxins on fish leukocytes

“…Cyanotoxins, which are mostly secondary metabolites of cyanobacteria, are responsible for a wide range of negative health effects in the intoxicated aquatic and terrestrial organisms [1,2]. During decay of cyanobacterial water blooms, the content of the bloom-forming cells is released into the water and cyanobacterial-derived toxic compounds may reach high concentrations, posing a threat to the organisms using such contaminated water.…”