Question to the Ministry of Defence:

To ask the Secretary of State for Defence, how many marmosets at DSTL Porton Down were culled on the grounds they were deemed to be (a) surplus animals and (b) unsuccessful breeding animals in each of the last 3 years.

The Defence Science and Technology Laboratory (Dstl) at Porton Down, Wiltshire, is licensed by the Home Office to conduct the Ministry of Defence's (MOD) in-house research involving the use of animals.

There are occasions when it is necessary to euthanise an animal for its own welfare or for the welfare of the remaining breeding population. Veterinary surgeons provide extensive advice on the welfare of the animals and on the overall health of the breeding colony.

For 2016, 2017 and 2018, no surplus marmosets were euthanised. Due to unsuccessful breeding, no marmosets were euthanised in 2016; for 2017, one breeding marmoset was euthanised, and for 2018, three breeding marmosets were euthanised on veterinary advice that it would not be good for the animal's welfare and/or may risk the animal's health to carry on breeding.

Dstl always considers what will be in the best interests for every animal's welfare and follows the Home Office's Animal in Science Regulation Unit's advice on rehoming and setting free, which is available to view on gov.uk.