Declawing larger cat species like lions and tigers negatively affects their muscular capabilities, a new study shows.
Declawing house cats to keep them from scratching people and furniture is controversial—and even banned in some countries and areas in the US—but the practice is not limited to house cats.
While it is illegal in the US to surgically modify an exotic animal, declawing is still done on large cats, often in an effort to allow cubs to more safely be handled in photo opportunities or for entertainment purposes.
“What people might not realize is that declawing a cat is not like trimming our fingernails; rather, it is removing part or all of the last bone of each digit,” says Adam Hartstone-Rose, professor of biological sciences at North Carolina State University and corresponding author of the research. “Like us, each cat finger has three bones, and declawing is literally cutting that third bone off at the joint.”
For the study, published in the journal Animals, the researchers looked at the muscular anatomy of over a dozen exotic cats—from smaller species including bobcats, servals, and ocelots, to lions and tigers—to determine the effect of declawing on their forelimb musculature.
They measured muscle density and mass, and also examined muscle fibers from both clawed and declawed exotic cats. They found that for the larger species declawing resulted in 73% lighter musculature in the forearm’s digital flexors.
These muscles are involved in unsheathing the claws. They also found that overall, forelimb strength decreased by 46% to 66%, depending on the size of the animal, and that other muscles in the forelimb did not compensate for these reductions.
“When you think about what declawing does functionally to a housecat, you hear about changes in scratching, walking, or using the litter box,” says lead author Lara Martens, an undergraduate student at NC State.
“But with big cats, there’s more force being put through the paws. So if you alter them, it is likely that the effects will be more extreme.”
This is because paw size and body mass don’t scale up at a 1:1 ratio. Paw area increases at a slower rate than does body mass (which is proportional to volume), so larger cats have smaller feet relative to their body size, and their paws must withstand more pressure.
“Additionally, big cats are more reliant on their forelimbs—they bear most of the weight, and these bigger cats use their forelimbs to grapple because they hunt much larger prey,” Martens says. “So biomechanically speaking, declawing has a more anatomically devastating effect in larger species.”
“As scientists, it is our job to objectively document the effects of this surgery on the animals,” Hartstone-Rose says, “but it is hard to ignore the cruelty of this practice. These are amazing animals, and we should not be allowed to cripple them, or any animals, in this way.”
The work was done in partnership with colleagues from Carolina Tiger Rescue, a sanctuary that rescues exotic carnivores, especially big cats, who have often been neglected or mistreated.
Source: NC State
