Some animals at the zoos in Madison and Milwaukee will receive an experimental Covid-19 vaccine, AP reports.

Animals susceptible to the respiratory disease are expected to be inoculated with the vaccine authorised by the US Department of Agriculture by late July.

No Covid-19 infections have been found in animals at the Milwaukee County Zoo or the Henry Vilas Zoo in Madison, but some of the big cats at the Bronx Zoo became sick when the pandemic was peaking in New York City.

At the Henry Vilas Zoo, deputy director Joseph Darcangelo said the vaccine will be given to great apes, tigers and lions, and members of the mustelid family, including otters, skunks and badgers, Wisconsin Public Radio News reported.