Scientists Put Dead Zebras in Cages to Study Anthrax Spread
Posted on April 23, 2013
Scientists put dead zebras in electrified cages to learn more abut how anthrax can spread. Anthrax is a disease caused by the bacteria Bacillus anthracis. Some scavengers, such as hyenas and vultures, have evolved to be able to digest infected carrion (decaying flesh) without contracting the infection. It was thought that scavengers played a key role in spreading anthrax through wildlife populations, but it turns out anthrax can spread just fine without scavengers. The international consortium of researchers were led by Steven Bellan, an ecologist at The University of Texas at Austin.
The researchers found seven zebra and one wildebeest that had just died in the wild from anthrax infection. All of the carcasses were left exactly where they fell, but four were protected from scavengers by electrified cages. The other four carcasses were left completely open to the elements. Samples were taken at regular intervals to see whether there was greater anthrax spore production in the scavenged carcasses and in the nearby soil. The researchers found that anthrax sporulation and contamination happened to a similar degree at both the scavenged and unscavenged carcasses.
Bellan said in a statement, "It appears that the anthrax bacteria can survive for some time in the carcass even though it may be competing with other bacteria. It also appears that fluids can escape from the carcass into the soil via mechanisms other than scavenging or through hemorrhages occurring at the time of death. It looks like bloating caused by gases produced during putrefaction and maggot feeding activity are capable of independently rupturing carcass skin."
The research was published here in the journal, Applied and Environmental Microbiology.