Washington, Jul 4 (IANS): The Oakland Zoo in California has inoculated some of its animals against Covid-19 this week using an experimental vaccine, according to a media report.

So far, the zoo has vaccinated tigers, grizzly and black bears, mountain lions and ferrets, Xinhua news agency quoted the San Francisco Chronicle report as saying.

The list of animals to receive a shot was selected because of their unique vulnerability for contracting Covid-19, according to Alex Herman, vice president of veterinary services at the Oakland Zoo.

"Those are real cases where animals have become mildly sick, gravely ill or even died, and that's why we're being so proactive," she was quoted as saying.

None of the animals at Oakland Zoo have gotten the virus, she added.

The vaccine was developed by the animal health company Zoetis.

It has been authorised for experimental use on a case by case basis by the US Department of Agriculture and the appropriate state veterinarians.

Oakland Zoo received its first shipment of 100 vaccine doses on June 29.

The company is donating more than 11,000 doses of its new vaccine to nearly 70 zoos, as well as more than a dozen conservatories, sanctuaries, academic institutions and government organisations in 27 states, according to Zoetis.