Is your cat in pain?

Here's how the experts can tell

Social life among cats can be pretty brutal. Generally speaking, the toughest, strongest animal counts as the top cat, and weaker individuals will get marginalized and bullied. So it is not surprising that cats have evolved to become masters at concealing pain and weakness.

For example, there are numerous cases of a cat going almost completely blind before her humans have noticed anything is amiss. To a cat, weakness means vulnerability, so pain is something to be concealed at all costs.

Often humans bringing their pet to the vet are surprised to discover that the cat has advanced arthritis, dental decay, or another condition which would have been obvious in a human long before. So how do you know if your cat is hurting? Two scientists, Isabella Merola and Daniel Mills set about trying to discover what signs indicate a cat in pain. Readers will be pleased to hear that the study was conducted completely ethically. Rather than subject any cats to pain (the results would not have been conclusive anyway), the researchers contacted a number of experts who regularly treat cats and conducted a survey of these experts asking what signs they looked for to diagnose that a cat was suffering.

The results were published on 24 February 2016 in a study entitled Behavioural Signs of Pain in Cats: An Expert Consensus. (http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0150040)

With humans it is relatively easy to tell pain. Firstly, those suffering generally let others know, and secondly, there are certain symptoms such as groans or screams (called 'vocalization' in the jargon) which are clear indicators. One surprising discovery from the study of pain in cats is that not all cats show pain in the same way, and there are no universal signs that show a cat is hurting.

Because of this the researchers observed that humans, especially untrained humans, are bad at diagnosing pain in cats. They comment, 'Owners may not always recognise the clinical relevance of all the observations that they make. For example, they may view them as an inevitable part of the natural ageing of the animal and not report them to the vet as a concern or at least not until they become quite severe.'

Some conditions always cause pain. Therefore the researchers contacted specialists in feline medicine who dealt with cases of cats with issues such as arthritis, cancer, dental problems, burns and physical trauma (such as injuries from road accidents or cat fights). On average each expert saw around ten cats a month which were suffering moderate to severe pain.

The scientists discovered that there is no single sign to say that a cat is suffering. For example you can't say 'the cat is not yowling, therefore she is not hurting'. They also discovered that changes in behaviour were almost as important as those behaviours in the first place. For example many cats of an irritable disposition are inclined to growl – however cats in pain are likely to growl more often. Again, a shy cat may be given to withdrawal, and hiding itself away for much of the day. But if a cat which was previously lively and sociable starts behaving in this way, then the cat might be hiding in order to hide pain.

Overall, the scientists came up with a list of almost two dozen behaviours which are common to cats in pain. Many of these behaviours might also be seen in cats that are not in pain, so one thing the experts stress is whether the cat is acting differently. If any of these types of behaviour are new, then the cat may need help. The main categories in the list are summarized as follows:

Mobility
Difficulty jumping. Trouble walking, or walking strangely. Being reluctant to move.

Posture
Crouching. Head drooping. Shifting weight. Tension around the eyes and muzzle.

Behaviour
Not playing. Not grooming. Reluctant to be touched. Hiding. Loss of appetite. Increased irritability.

Vocalizing
Yowling. Growling. Groaning. Yelping.

Other
Excessive salivation. Trembling or shivering.

The experts also observed that cats in extreme pain often pant, or might have dilated pupils and very tightly closed eyes (blepharospasm).

As a result of the study the scientists observed 'None of the ... signs was considered necessary to denote pain (i.e. if this sign is absent we cannot consider the subject to be in pain), if this sign is present the subject is in pain, but its absence does not exclude the presence of pain.'

In other words, if a cat shows one of the signs listed here, that cat might or might not be in pain, but the more signs the cat exhibits the more likely that the cat is in pain and the more likely it is that the pain is severe. How an individual cat shows pain depends on her personality, her current mood, and her relationship with her humans.

It does not help, remark the researchers, that untrained humans are bad at analyzing their cats. They tend to give them complex human emotions and motives which the cat does not really have. As a result the humans often miss the basic message. 'This hurts. I need help.'

Note: This information is for guidance only. It is not intended to replace consultation with a licensed practitioner.