Algal Composition Of Georgia Ponds Used For Drinking By Domestic Cattle
Abstract
Despite our best efforts to ensure the health of our livestock and pets, they may be exposed to various threats to their lives. Unknown to most people, a wide variety of naturally occurring cyanobacteria could be producing toxins in any pond or stream. Animals drink water and consume mats with potentially high content of cyanotoxins, but exposure is often underestimated. Evaluation of exposure to algal toxins by cattle is important for human health as well because toxins are naturally stable compounds which could undergo bioaccumulation, thus infecting one of our largest food sources. In this study, the presence of toxin-producing cyanobacterial populations in natural water supplies for domestic cattle were analyzed. For analysis, water samples were taken from five rural locations in west Georgia. Triplicate samples were gathered monthly from June to September following standard protocol. Each site served as a natural water source for domestic cattle. Algal community structure and composition were evaluated in each sample. 93% of sites showed Shannon Diversity Index values ranging from 1.7-2.3 and high group richness. In pond samples, green filamentous algae were dominant, accounting for about 70% of algal diversity, while diatoms dominated streams, usually accounting for 80% of diversity. Cyanobacteria capable of producing toxins were present in all sample sites and higher numbers of cyanobacterial genera typically occurred in areas where cattle were not present or reluctant to approach, as observed and reported by the owners of the cattle. This would suggest that the aquatic environment, which serves as suitable drinking water for cattle, is not a suitable habitat for cyanobacterial growth. Cattle disturb water column stratification, reduce light availability, and reduce algal growth. In addition, domestic cattle potentially sense a natural cue not to consume water which has a dense population of cyanobacteria.
Algal Composition Of Georgia Ponds Used For Drinking By Domestic Cattle
Despite our best efforts to ensure the health of our livestock and pets, they may be exposed to various threats to their lives. Unknown to most people, a wide variety of naturally occurring cyanobacteria could be producing toxins in any pond or stream. Animals drink water and consume mats with potentially high content of cyanotoxins, but exposure is often underestimated. Evaluation of exposure to algal toxins by cattle is important for human health as well because toxins are naturally stable compounds which could undergo bioaccumulation, thus infecting one of our largest food sources. In this study, the presence of toxin-producing cyanobacterial populations in natural water supplies for domestic cattle were analyzed. For analysis, water samples were taken from five rural locations in west Georgia. Triplicate samples were gathered monthly from June to September following standard protocol. Each site served as a natural water source for domestic cattle. Algal community structure and composition were evaluated in each sample. 93% of sites showed Shannon Diversity Index values ranging from 1.7-2.3 and high group richness. In pond samples, green filamentous algae were dominant, accounting for about 70% of algal diversity, while diatoms dominated streams, usually accounting for 80% of diversity. Cyanobacteria capable of producing toxins were present in all sample sites and higher numbers of cyanobacterial genera typically occurred in areas where cattle were not present or reluctant to approach, as observed and reported by the owners of the cattle. This would suggest that the aquatic environment, which serves as suitable drinking water for cattle, is not a suitable habitat for cyanobacterial growth. Cattle disturb water column stratification, reduce light availability, and reduce algal growth. In addition, domestic cattle potentially sense a natural cue not to consume water which has a dense population of cyanobacteria.