"We are very grateful that this has been brought to our attention," Crystal Walsh of the Aurora Chamber of Commerce told The Dodo.
Walsh says organizers "are not going to hire this company in the future or have an event of that nature."
Tiger Paw Exotics, a traveling zoo that bills itself as "family-oriented" on its website, responded by email several days after the story was published.
In a statement, zoo owner Tim Height called reports about the condition of the animals "false and outright lies."
Height noted when his staff was setting up the zoo, "the weather was overcast and cool."
"At the time when the photo of the kangaroo was taken the sun had just broken through."
In addition, he explained, "kangaroos in their native land relax and sleep during the day and are active in the morning and evening."
But it isn't the first time Height's company has been the subject of complaints about its animals. Tiger Paw Exotics came under fire in March for its treatment of a camel at another event, which seemed to be ailing in a small enclosure.