The researchers modelled the effect of removing sick animals on the disease's prevalence in a small population.
SeaWorld says it supports wildlife conservation, research and education and has rescued thousands of stranded and sick animals.
As part of the trial cull, researchers have trapped and euthanised sick animals two to five times a year from an isolated population in the south-east of Tasmania.
The study, in the Journal of Applied Ecology, seems to confirm findings in wild trials, that selective culling of sick animals is ineffectual at stopping the spread of the disease.
Sick animals often have higher white-cell counts as their bodies churn out more ammunition to fight the infection, but those in the Virginian study all came from zoos, and were believed to be hale and hearty.
Current methods for detecting disease in livestock are slow and open to abuse, because they rely upon farmers or vets reporting sick animals, says Marcus Doherr of the Institute of Animal Neurology at the University of Bern in Switzerland.
China's government has also advised people to maintain good personal hygiene, including frequent hand-washing and avoid direct contact with sick or dead animals.
The court heard how he failed to feed his entire herd adequately and did not treat, or seek veterinary treatment for, sick or injured animals.
In early 19th- century Pennsylvania, this goo was considered a depressor of property values because oil made it hard to grow crops and made farm animals sick.
The Chinese government has stepped up its disease surveillance, and has advised people to maintain good personal hygiene, including frequent hand-washing and avoiding direct contact with sick or dead animals.
While the source of the pigs is being sought, rumors have it that livestock upriver are dying of disease and authorities have cracked down on the sale of sick and dead animals to abattoirs.
Cloning creates abnormalities in the genetic read-out, which is the reason that cloned animals are so often sick.
CNN: Human stem cell cloning: 'Holy Grail' or techno-fantasy?
The sheep were put down last month when a lorry was stopped at the port and the animals were found to be sick and lame.
Forty four sheep were put down at Ramsgate in September when a lorry was stopped at the port and the animals were found to be sick and lame.
In some cases, we take animals who are healthy and we make them sick so we can study them, and that, obviously, is a lot more ethically complicated.
While some people may regard the use of animals as drug factories as unethical, however, the use of genetic engineering to treat the sick might be regarded as more acceptable than its use to increase yields and profits in agriculture.
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