"On the 8th of August, cat lovers around the world will celebrate a day dedicated to all things fantastic and fascinating about felines.
"There will be homes around the world where cats and kittens are lucky enough to spend their lives protected by the security of a loving family.
"Sadly, behind other closed doors – not of homes but of laboratories – there will also be many other cats and kittens suffering in silence.
"This time last year, one of our investigators, Suzie, was undercover at a MSD Animal Health laboratory and reflects on the time she spent with the kittens used in research. Please read her words and take action to stop this suffering by signing up to our Thunderclap for World Cat Day to raise vital awareness about the investigation and to end these cruel and unnecessary practices."