An anti-hunting activist told ITV News Correspondent Rupert Evelyn the dogs are killed and "thrown away like garbage" when they are no longer "fit for purpose"
Secret cameras have recorded huntsmen shooting and killing hounds that had been used for hunting.
The pictures, filmed by anti-hunting groups the Hunt Investigation Team and Keep the Ban and shared exclusively with ITV News, is the first time footage of a hunt shooting its hounds has been shown publicly.
Hounds can be killed for several reasons including being too old to hunt, or if they get ill or injured. The practice is not illegal.
The pictures were taken at the kennels of the Duke of Beaufort's Hunt in Badminton, Gloucestershire. The Duke of Beaufort's Hunt told ITV News that its hounds are "humanely euthanised" if they cannot be rehomed. It added that the majority of hounds are "unsuitable for rehoming" because "they are not house-trained and have only ever been used to living in a pack environment".
The secret footage, recorded over several periods between April and September, shows four separate examples of hounds being shot:
In two cases, a huntsman is seen putting a gun to the head of the hound and killing it.
In another, the hound appears to be unwell and is carried onto the grass by the hunt staff before being shot.
Another shows the hound being shot twice, three minutes apart.
Watch the secret footage at a hunt's kennels where hounds were filmed being shot dead
Rob Pownall, Keep The Ban founder, said: "It's some pretty upsetting footage but this is commonplace for hunts across the country. This is not an acceptable way to end an animal's life. These hounds suffered immense pain. "The activities shown in the video aren't actually illegal, but there's no moral defence for what's shown."
The footage comes ahead of a vote later this month by National Trust members to decide whether trail hunts on its land should be banned during the next hunting season.
The National Trust suspended all trail hunting licences last year, alongside a host of other large landowners including Forestry England, following a report by ITV News about the content of webinars hosted by the Hunting Office.
Conservative MP Tracey Crouch, who is co-chair of the All-Party Parliamentary Group for Animal Welfare, said the footage of the hounds being shot dead is "absolutely heartbreaking" and "distressing".
"I don't understand why a dog...needs to be euthanised in this way and I am sure there are much more compassionate ways of putting a dog to sleep", Ms Crouch told ITV News.
"We have many working dogs across this country in different sectors, such as, for example, the police or army, and I doubt very much that those kinds of dogs are put to sleep with a bolt to the head, so I don't quite understand why it is appropriate for hunting hounds to be euthanised this way."
After watching the secret filming, Mike Jessop, a fellow of the Royal College of Veterinary Surgeons, said that from what he saw, he did not believe the huntsmen were professionally trained in putting animals down. "There was no evidence of [the huntsperson] being veterinary trained or veterinary surgeons. The lack of use of any veterinary equipment that one would expect such as stethoscopes to ascertain the dogs were dead was just lacking", he said. "The evidence from the video doesn't show any illegal activity. My concern is whether there is any suffering after the shot, because nobody is being careful enough in checking the dogs are truly dead. "In one of the videos, the [hound's] tail was still waggling very vigorously for quite some time, even when the dog was being loaded in the wheelbarrow.
"I would question, and be concerned, that that dog was still sentient, and therefore had the ability to feel pain." "I would hope that the procedure was being done by a veterinary surgeon in a more humane way, by use of lethal injection, rather than bullet."
Kennelmen and women have to make 'terrible decisions' when hounds reach the end of their working lives, says Charlie Jacoby of the Fieldsports Channel
Charlie Jacoby of the Fieldsports Channel, which covers hunting, shooting and fishing, said that while the kennelmen and women who look after hounds are devoted to them, they also have to be 'unsentimental' and make 'terrible decisions' at the end of their working lives.
"If you're dealing with...hounds at scale, you're going to have to deal with the end of their working life and that will probably mean, sadly - and it is a terrible job - putting them down", Mr Jacoby said. Asked by ITV News Correspondent Rupert Evelyn about whether there was a more humane way of killing hounds, Mr Jacoby said: "If you have got hounds that are born in a kennel and brought up in a kennel, taking them to a vet is an option, [but] the vet smells of death, of chemicals. It is far better to do it in a kennel, I would say."
Responding to the footage, comedian and supporter of animal rights Ricky Gervais told ITV News: "It is so deeply upsetting that foxhounds are trained against their natural instinct to hunt foxes and when they catch them, rip them to pieces!"
"Then they are killed, usually by a shot to the head, by...someone who loves to chase and kill innocent animals. Both the hound and the fox become the victim of this cruelty. It's insane, don't you think?"
In a statement about the secret filming of the hounds being killed at its kennels, the Duke of Beaufort's Hunt told ITV News: "A number of options are considered for every hound before any decision is made regarding their future, whether that is retirement or rehoming, either to a domestic environment or to another kennels where their country may be deemed more suitable for that individual hound.
"Occasionally hounds are successfully retired as domestic pets, but they are not house-trained and have only ever been used to living in a pack environment so the majority are unfortunately unsuitable for rehoming.
"Where other options are not available, hounds are humanely euthanised. This is done by trained professionals using lawful and approved methods."