Thanks, in all likelihood, to a tuberculosis-infected badger, a zoo in England has had to put 60 mammal species on birth control via injections, implants, tablets, and IUDs, the BBC reports. And, yes, that includes lions and tigers, according to the Times. The large cats must be knocked out with a dart gun before receiving their contraception injection. The Telegraph reports 11 antelopes at Paignton Zoo had to be killed last summer after one was found to be infected with TB. The disease is believed to have originated with a badger. Government rules say no animals can be transferred from the zoo until the end of the year at earliest to prevent the spread of TB. That's left the zoo concerned about overcrowding.
As part of its breeding program, Paignton usually sends animals to hundreds of zoos around the world. Now if it doesn't stop its mammals from breeding, it could run out of space. "We must prevent overcrowding, but we must still be in a position to take part in breeding programs when the restrictions are lifted," says Ghislaine Sayers, the zoo's head vet. "So we need temporary solutions." There are risks involved with giving animals contraception: It can wear off too quickly and allow them to become pregnant; it can cause young animals to become sterile; and it can cause male animals to lose muscle. "And animals are individuals, so—like humans—some contraceptives suit some better than others," Sayers says. The zoo is consulting with experts around Europe and will test its animals for TB again in six months. It also plans on improving fencing to keep badgers out. (The diet of captive gorillas could be killing them.)