We have 2.5 million feral cats in New Zealand; on top of that, about 44 per cent of households have at least one moggie. Females can have up to 200 kittens in their lifespan. But US scientists have discovered what might prove a breakthrough: a single-dose contraceptive injection that suppresses ovulation, apparently with no adverse side effects.
In the two-year study, six adult cats—all named after former US First Ladies—were injected with an anti-Müllerian hormone transgene that prevents ovulation follicles maturing. Despite spending long days with a fertile tom, and some of them mating multiple times (meow, get it, Dolly and Barbara!), none of these females conceived. The control group—three cats who were not given the injection—had 21 kittens over the course of the study.