Animal Rights activists staged a protest outside the premises of MSD Animal Health yesterday morning.
The protesters were alerting motorists by Walton Manor to their cause with the support of a banner, emblazoned with the words 'Stop Torturing Animals.'
The group said they believe that MSD Animal Health still test on animals at the premises.
Last month, a spokesman for MSD Animal Health told Total MK: "MSD Animal Health no longer has research facilities in Milton Keynes.
"Laboratory animal research is indispensable to the discovery, development, manufacture and marketing of innovative medicines that protect the health of pets and animals, and help control the spread of disease."
They added: "MSD Animal Health makes decisions regarding animal use and welfare by balancing scientific and regulatory requirements with strong consideration of ethical, welfare and societal values.
"We are dedicated to the ethical and responsible treatment of all animals involved in the development of medicines and vaccines, and further, we place significant emphasis on the development, validation and acceptance of alternative approaches to animal testing."
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