Hunting should be suspended while the Government investigates the scale of bovine tuberculosis among fox hounds, ministers have been told.
Labour former frontbencher Paul Flynn warned there is a "very substantial" danger of hounds spreading bovine TB given the amount of land they cover when active on trail hunting or chasing a fox.
MPs heard the Kimblewick Hunt, which operates within the south east, had to put down 25 fox hounds after they contracted the disease while a further 120 were tested.
Mr Flynn said the outbreak suggested there is a need for a new investigation into the prevalence of bovine TB among fox hounds, with hunting suspended until the level of risk has been assessed.
He made the remarks as MPs debated a petition calling for the end of the badger cull, amid fears tens of thousands of healthy badgers could be killed in a bid to control bovine TB.
The petitioners, who number more than 108,000, say they acknowledge the disease is a "serious problem" but believe any solution needs to involve measures such as a vaccine and increased cattle movement control measures.
The Government argues it is pursuing a "comprehensive bovine TB eradication strategy", labelling the disease as the "greatest animal health threat to the UK" with 28,000 cattle slaughtered in England in 2016.
Mr Flynn (Newport West) said the Government's badger cull policy is "evidence-free and prejudice rich", claiming ministers have a "long record" in trying to "appease farmers".
He added culling appears to be a simple solution by those who believe in "shooting first and thinking later", with the Government using a "very rusty tool out of a medieval box".
Speaking during a Westminster Hall debate, Mr Flynn said of the Kimblewick Hunt: "The fact that 25 fox hounds had to be put down because they were infected with bovine TB, with a further 120 undergoing testing, has been a cause for serious worry.
"I've asked the Government what they're going to do about this because this wasn't seen as a threat in the past.
"There are few animals that are free to cover and infect more territory than hounds when they're active on trail hunting or chasing the fox.
"This is a really serious new risk we have before us.
"The news has been kept quiet since December but the hunt suspended hunting themselves, however, it's carrying on apparently using visiting packs."
Mr Flynn went on: "The danger does seem to be a very substantial one.
"I believe there is evidence here for a new investigation into the prevalence of bovine TB among fox hounds, and a case for saying hunting should be suspended until that has been proved to be a risk or to not be a risk.
"Let's put that to the test."
Conservative Richard Drax (South Dorset) suggested those who oppose the cull should not view the badger as a "friendly, loveable animal" but as a "danger" to other animals and parts of the natural environment.
He said: "Like all wild animals they should be culled so the numbers should be maintained because it has no natural predator, just like deer or foxes."
Angela Smith, Labour MP for Penistone and Stocksbridge, accused the Government of showing a "cavalier attitude towards the science relating to this issue".
She said: "As time has gone on we have witnessed a blatant refusal by government to follow the science."
Ms Smith said badger culling has been "discredited".
"It has no basis in science because the science has been distorted then twisted and then in the end utterly abandoned," she said.
She called for the Government to carry out a full evaluation of the culling carried out so far to ascertain its effectiveness.
Tory Sir Roger Gale (North Thanet) called on ministers to stop going down a "blind alley" pursuing a "policy that doesn't work, hasn't worked, will not work" and instead put the same resources into finding a TB vaccination that works for cattle and badgers.
He said: "I believe that we are going down the wrong path and I don't say that with any pleasure whatsoever.
"If it worked, if it eliminated TB in badgers and TB in cattle, then I could probably live with the fact that it was necessary because in the long run it would be the kindest thing to do.
"But we don't know how many of these 15,000 slaughtered badgers have had TB even because they have not been tested.
"Where is the science in that? We don't know whether it's cattle giving TB to badgers or badgers giving TB to cattle or both because that hasn't been proven."