In February 2024, a regulation on animal welfare and safety* will come into force in Quebec: it will notably prohibit the declawing of cats or onyxectomy. Beyond the ethical questioning with regard to this practice, various studies have suggested or demonstrated its negative effects on the overall health of the animal.
This was argued by Professors Éric Troncy, Bertrand Lussier and Aude Castel, members of the Animal Pharmacology Research Group of Quebec (GREPAQ) of the Faculty of Veterinary Medicine of the University of Montreal, on the occasion from 90e Acfas Congress. They were accompanied by D.r Jordyn Hewer and Alexandra Yaksich, who contributed to the adoption of this new regulation by acting as spokesperson for the Collective of veterinarians, animal health technicians and the public against declawing.
An amputation with physical and psychological effects
Onyxectomy is a surgical procedure that involves amputating the third phalanx of each finger of cats, thus eliminating their claws. However, this operation has its share of negative effects on their overall health.
In fact, studies indicate that onyxectomy contributes to the appearance of problems of uncleanliness and aggressiveness. According to one of them, in a third of declawed cats, this intervention leads to at least one behavioral problem. Similarly, 18% of cats who have been declawed will bite more and 15% have problems with dirtiness.
“Cats can also suffer from chronic pain and therefore behavior problems after declawing,” said veterinary surgeon Bertrand Lussier.
“Nerve severing can cause tactile sensitivity and phantom pain,” said Aude Castel. If a declawed cat relieves itself outside of its litter box, it could be the consequence of an unpleasant feeling associated with a new hypersensitivity to gravel.
The veterinarian neurologist also explained that onyxectomy can have consequences on the aging of the nervous system of cats, favoring the appearance of conditions such as osteoarthritis, but also chronic pain, which accelerates cognitive decline.
And what about the operation performed using a laser that is supposed to reduce pain?
“Tendonectomy, which involves cutting a tendon to prevent retraction of the phalanx, is a solution to declawing. It attenuates the deleterious effects of onyxectomy according to a recent study, but it is no less painful and could also have long-term consequences,” said Bertrand Lussier.
Other solutions to declawing include claw guards (plastic caps), regular claw trimming and the use of a scratching post using positive reinforcement behavioral strategies.
“The ban on practicing onyxectomy and its variants will allow Quebec to join the ranks of many countries that have banned this practice for a long time, including France, observed veterinary algologist Éric Troncy. In Canada, only the provinces of Quebec and Ontario still allow it to this day.
Studying the pain felt by cats
Credit: Amélie Philibert | Montreal university
According to Éric Troncy, knowledge of pain in cats has greatly evolved over the past two decades “notably thanks to the creation – 12 years ago – of a study program on the modifications and sensory damage to cats that come with age, using a colony of cats, he reported. We are the only ones to have such a program”.
According to him and his colleagues, many cats hide their pain so well that even veterinarians have difficulty detecting it.
“The cat is a predator, but also a potential prey and it is to its advantage to mask the pain so as not to appear vulnerable, concluded Aude Castel. But he may be in pain even if he doesn’t express it by meowing or vocalizing.”
* This is the Regulation respecting the well-being and safety of domestic pets and equines, which notably provides for the prohibition of cosmetic surgeries such as declawing, tail docking, ear pruning and devocalization .
Objective data on the consequences of onyxectomy
The analysis of the long-term consequences of declawing poses a challenge to researchers because of their intertwining with the emergence of age-related diseases, in particular osteoarthritis, which is almost inevitable in aging cats.
As part of a meta-analysis he carried out at GREPAQ, Dr.r Mathieu Lachance wanted to decide between these consequences by collecting data on 24 healthy cats, 125 non-declawed cats with osteoarthritis and 39 declawed cats.
It shows that, if osteoarthritis alters the gait of older cats, this alteration is amplified by declawing – and the larger a cat, the less weight it will place, proportionally, on its osteoarthritic and declawed limbs. This podobarometric deficit is accompanied by increased tactile sensitivity in declawed and osteoarthritic cats, compared to osteoarthritic cats that have not undergone an onyxectomy and even more so compared to healthy cats.
These assessments were made possible thanks to the acquisition by GREPAQ of expertise relating to various complex methodologies which objectify for the first time in the world the deleterious consequences of declawing on animal well-being.
“Although previous studies had illustrated the behavioral disorders of declawed cats, none analyzed them with a comparable group to highlight the effect of declawing or they had been carried out very shortly after onyxectomy and did not bring any conclusion on this intervention,” said Éric Troncy.