An imported alpaca infected with tuberculosis must be killed, a judge has ruled following a four-year quarantine saga.

       Geronimo, a stud from Gloucestershire, is set to be slaughtered after an appeal to have the animal re-tested for the deadly disease was refused by the High Court on Thursday.

       It tested positive for bovine tuberculosis (bTB) twice after being imported from New Zealand in 2017. But Geronimo's owner, Helen Macdonald, said there was a high risk that those results were false.

       She claimed that the Department for Environment, Food and Rural Affairs (Defra) relied on "flawed science" to support the cull, as Geronimo had not exhibited any sign of illness in the UK and lived longer than an infected alpaca would have done. The alpaca also tested negative in New Zealand before arriving.

       However, her legal appeal for a re-test has now been refused and Defra can legally kill Geronimo. A warrant for its cull will be in effect from Aug 5.

       It is the first case of its kind to ever pass through the High Court in London.

       Ms Macdonald, 50, said outside court: "I believe I can have him put to sleep or a contractor will come and shoot him. But I will do right by him and I will have him put to sleep. It will be on his terms, on my terms.

       "He's had a good life, but he should have had another 10 years."

       Geronimo has been in quarantine with five other alpacas on Ms Macdonald's farm in Wickwar, near Bristol, since arriving in the UK in August 2017.

       It had tested negative for bTB in New Zealand, but when Ms Macdonald agreed to a voluntary test as part of national surveillance of the disease, the result came back positive.

       Defra decided to conduct a second test in November 2017, which also came back positive, and Geronimo was earmarked for slaughter.

       bTB is caused by a bacterium called Mycobacterium bovis (M. bovis), which is closely related to the bacterium that causes human and avian tuberculosis. All mammalian species, including humans, can catch it.

       Methods of transmission include through consuming unpasteurised milk or dairy products from an infected animal, or inhaling bacteria exhaled by an infected animal.

       Legally, Defra only needs to suspect the disease is present to order the slaughter of animals and limit its spread.

       It is illegal to test an animal without permission. Ms Macdonald called for Geronimo to be re-tested, but Defra refused. She challenged the refusal in the High Court in 2019, but the original decision was upheld.

       Her second appeal reversal marks the end of a painful and costly journey for Ms Macdonald, who has been unable to trade livestock at her farm due to the restrictions in place while Geronimo was quarantining.

       There is a legal requirement to report bTB if it is present or suspected to be present in a herd, but there is no requirement for alpacas to be regularly tested.

       The British Alpaca Society is calling for more research into bTB testing. Duncan Pullar, chief executive of the body, said: "The system was put in place to test TB in cattle. There will be some false positives and some false negatives.

       "It's frustrating that there are no learning opportunities as to why he is fit and healthy but has a failed test against his name."

       A Defra spokesperson said: “We are sympathetic to Ms Macdonald’s situation – just as we are with everyone with animals affected by this terrible disease.

       "It is for this reason that the testing results and options for Geronimo have been very carefully considered by Defra, the Animal and Plant Health Agency, and its veterinary experts, as well as passing several stages of thorough legal scrutiny.

       “Bovine TB causes devastation and distress for farmers and rural communities and that is why we need to do everything we can to reduce the risk of the disease spreading.”