Welcome to my presentation on the rabbit grammar grey scale, I'm using it to more accurately assess pain in rabbits. So how do we assess pain in rabbits or any other small animal that we routinely see in clinical practise? Well, the assessment of pain is quite difficult because pain is a subjective experience, meaning that direct assessment of that experience is very difficult, not impossible but difficult.

Because animals, unlike humans, we do not have a gold standard means of assessing their pain. The reason for this is that they cannot self report. They cannot tell us very in a meaningful way, how much pain they are in.

Therefore, what we are left with doing is using proxy indices of pain based upon the principles of inferential reasoning. I.e., making generalisations from human responses to pain, so if something, causes a cha, if pain causes a change in our behaviour, we associate that change in behaviour with pain.

If animals show a similar change in response to a similar pain stimulus, then we can assume that behaviour also indicates pain in that species. So what makes an effective method of assessing pain? Well actually what makes an effective method of assessing anything.

So for humans and animals, effective indices of pain should be valid. They should measure what they claim to measure. They should be able to accurately differentiate a painful animal from a non-painful animal.

They should be highly reliable, both in with both high internal consistency and high integrated reliability. So all that means is that they are reliably consistent when the same person uses them to look at different animals or when different people are looking at the same animals. In both cases, but the same score is always given.

They should be sensitive. They, so changes in the indices that we use to assess pain should relate to the changes in pain severity expressed by an animal, or experienced by an animal. And finally, and probably one of the most important criteria is that they should be easily implemented clinically, i.e., they should have clinical utility.

There is no point in using a measure that cannot be applied within clinical practise. So how do we identify effective pain in disease? Well, it's quite simple, there is an underlying principle to any being able to determine whether any behaviour or physiological change is sensitive to pain.

If pain causes an index to change in its intensity with which it's expressed, then we can assume that it's pain related. And then if we try different methods of ameliating pain and those methods cause a reduction in the change intensity in response to pain, for example, giving analgesia, we can assume that that index is sensitive to pain. So therefore what we have there is a pain specific index.

So coming back to our underlying problem of assessing pain in nonverbal species, and I should point out at this point that also includes nonverbal humans. So back in 1987, Granu and Craig suggested that we should use the same approaches that we use with nonverbal humans as a framework for assessing pain in animals. And unfortunately, we seem to have forgotten about that for about the last 20 years before coming back round to this idea, and asking the question, how do we assess pain in, in humans that cannot meaningfully communicate their pain to the people who care for them.

And the answer to that question is using facial expressions. So in the very young and the very old, we use facial expressions. In both of these photographs, I hope you see pain.

These are two classic pain faces in a baby and an older adult. Why do we consider facial expressions to be such a good means of assessing pain in the nonverbal? Well, they offer us a very effective method using a limited number of indicators, in this case, facial expressions.

It's very rapid and easy to carry out with minimal training. With a manual, you can pretty much learn to be about 95% specific within a very short period of time. Facial expressions are considered to represent a much more generic response to pain than many other indices we use to assess pain in the nonverbal.

They have very high accuracy of over 95% and they utilise the human intensity to fixate on faces. And a good example of this is this photograph. You will see a face.

It's actually a rock structure on the surface of the moon, but because it had what appears to be two eyes, a nose and a mouth, your brain sees a face. And we fix 8 on faces, so when we are talking to people, when we are looking around, we are all subconsciously scanning facial expressions to try and understand how people are feeling. And as a result, facial expressions are considered to be a gold standard means of assessment in the nonverbal.

Just to demonstrate that in relation to animals, a few years ago we did a study here in Newcastle looking at where people looked on the body of a rabbit when they were trying to assess pain. And what we found is that they naturally focus on the face. And you can clearly see that from this figure in terms of the frequency with which the face was observed in a very short video sequence clip of a rabbit.

If we look at the amount of time in that clip that they look at the different areas of the body, you can clearly see again we get the same pattern that we fixate on faces. So we, so we should use this natural fixation on the faces and exploit this in terms of assessing pain. So how do we assess or how do we measure facial expressions?

We assess facial expressions by measuring the changes in different components that comprise an individual facial expression. These individual components are called action units or AUs, and a facial expression comprises one or more action units. So what you can see here is a nice passport photo of me and that passport facial expression is comprised of the action units to the right.

So what you have is my eyebrows, you have my eyes, you have the top of my nose. You also have my ears, my cheeks, my nostrils. My upper lip, you have my mouth, my lower lip, and my jawline, all of those different components make that facial expression.

The subset of all the facial expressions an animal or a human expresses that are sensitive to pain. So there's, there's always a subset that is going to be sensitive to pain and that subset is referred to, at least with animals, as a grim scape. So these are the action units associated with pain in humans.

Action unit 4, brow lowering, action unit 43, eye closing, action unit 6, cheek raising, action unit 12, lip corner pulling, action unit 25, parted lips, action unit 10, upper lip raising, action unit 9, nose wrinkling, and action unit 7, I needs tightening. So of all of the different action units or components of my facial expression that humans can. Can express, these are the ones that are sensitive to pain.

Well, interestingly, these action units are also the ones that animals seem to exhibit when in pain. So facial expressions, this should be no great surprise to us because facial expressions have evolved. You are not born with them.

As a consequence, animals share many of the changes in many of the components of facial expressions that are responsive to pain. Therefore they are species generic. So we see changes in the eyes, the cheeks, the ears, the whiskers, the mouth and the jawline, in mice, in horses, in adults and baby humans, as well as in rabbits.

Now the exact changes in these areas might differ between species, but what we see generally is changes in those areas. So coming on to moving on to how we use facial expressions to assess pain in humans, what we have here is the what we call the Grimma scales, and there are various grimma scales available. How were they developed?

Well, they were developed in the same way that human facial coding experts developed coding systems for humans. We simply compared images of the same individual in a pain state and non-pain state and identified what changes between the non-pa state and the pain state. From that list we identify our potential action units.

Those action units are scored based upon the intensity or presence of those action units on a 3 point scale. If an action unit is not present, you give it a score of 0, if an action unit is moderately present, you give it a score of 1, and if an action unit is obviously present, you give it a score of 2. The scoring system will become much clearer and much more apparent when I actually show you the rabbit grim scale in a moment.

From the, now we can, as a general rule, when scoring animals using grimmer scales, we actually use the overall grimmer score as our determinant of whether the animal is in pain or not. And there are two kind of grimmer scores that we can use. We can either take an average of the individual action units in scale.

Or we can add them all together to give us a total composite of all of the individual actions in the scale. Now these two methods are interchangeable. The where, the one that I, I always think that the total composite score is easier to do clinically because you simply add them together.

But the advantage to the averaging the individual action units, just to have an average of all of the action units, is that this is a lot less sensitive to what we think of as missing values. So if you can't get a score for a particular action unit, this using the average is much more sensitive and can be better in those scenarios. So there are lots of grimmer scales available at the moment and more being developed all the time.

This is some examples of the ones that I've been involved in developing or testing and validating. So we have mouse and rat groomer scales, we have a rabbit groomer scale, which I'm going to detail in in much more detail later. We have two horse grimmer scales, we have a cat scale, we have sheep scale, and we have a cow scale, to name but a few.

And you can see the references for these individual scales should you be interested in those. So moving on to the topic of this presentation, the Rabbit Grimma Scale. Now the rabbit Grimace Scale was developed here at Newcastle, in collaboration with my colleagues Steph Keating and Professor Paul Flecknell.

And the rabeck groomer scale has 5 action units associated with it orbital tightening, cheek flattening, nose or nostril shape, ear shape the position, and whisk position and whisky shape. I'm now going to go through each of those individual actions in detail to explain what each action it looks like at each scoring level. So the first action unit is orbital tightening.

This interestingly, this action unit is seen in all the species that we have from the scales for. So under normal non-painful situation, this actually the eyes of these rabbits are generally nice and bright and open, and you can see this on the left of the left picture and we give that a score of 0. As we move across from left to right, you can see this rabbit's eyes are closing, so we're at a score of 1 or moderate, the the eye is just short of half closed.

At on the right hand side, we would score the I which is almost completely closed or completely closed as a score of 2 or obvious. So this action unit refers to closing of the eyelid or narrowing the orbital area. Over a score of sorry, with the eye being over half closed, we give it a score of 2.

A score of 2 is often, often also includes an eye squeeze, which is the contraction of the muscles around the eye and the eye is tightly closed. Just to give you an alternative view of orbital tight, so this is when the animal is in portrait, so facing you, you again can see each of the levels at 0, not present, 1 or moderate, and 2 for obviously present. The next action unit in the rabbit grim scale is cheek flattening.

This refers to the the cheeks just below the eye in front of the whisker pads back to the back of the jaw. And under normal circumstances, a rabbit's cheeks are nice and rounded and bulging. When in pain, these cheeks seem to lose that rounded bulging shape, bulging shape and become much flatter.

At a score of 2, the cheeks often look really quite sunken, and you can obviously see that in the example on the right hand side of a score of 2, and obvious score of 2 for cheek flattening. You can see that this rabbit's face is quite cheeks are quite sunken. Also, the cheek when in pain, the cheek muscles lose their definition or their visibility, and at a score of 2, the edges of the cheek, particularly the rear edges, close to the back of the jaw, become almost invisible.

And we also see generally that the rabbit's face shape goes from being quite randed and bulging to increasingly angular as the, as pain develops. So if you look across this panel of pictures from left to right, 0 to 2, you can clearly see that this rabbit's cheeks are flattening, its face is becoming much more angular and profile. This is just an alternative, portrait view of cheek flattening just to give you another view.

Again, you can see as you go across the panel of pictures from the left to right, this rabbit's cheeks are clearly flattening, and you can clearly see the sunken appearance at a score of 2. The 3rd action unit is nostril or nose shape, and this refers to the lairs or the nostrils of the rabbit. Under normal circumstances, rabbits' nostrils have a gentle U shape.

When in pain, that U shape becomes much more B in profile. So you can clearly see in the panel of pictures from left to right that the upper edge of the nostrils loses that gentle U shape profile and becomes much more V shaped. For the lower edge of the nostrils, again, it loses that curved profile and becomes increasingly straighter and drawn more vertically.

Please note that the openness of the nostrils is not related to the nostril shape in terms of scoring. That rates to the rabbit breathing, and it doesn't seem to bear any relation to the amount of pain experienced. So again, as you go across this panel of pictures from left to right, you can clearly see that this rabbit's nostrils are going from a gentle U shape to a much tighter V shape.

This is the alternative view, so you can clearly see here again, just to give you another view of what you're trying to score. And again across this panel of pictures from left to right, you can clearly see this rabbit's nostrils are increasingly going from a U shape to a V shape. The predominant sorry the pre pre-ultimate action unit is ear position and ear shape.

So under normal circumstances, a rabbit's ears are open, quite dish-shaped and facing any income any incoming sound. When the rabbit's in pain, the ear apertures, lose their open dishshaped appearance and become increasingly folded or curled inwards, i.e., they become much more cylindrical in profile.

One way to notice this change is to look at the distance between the inside edges at the base of the ears. And as the, the ears close or become much more cylindrical, that distance decreases. At a score of 2, the base of the inside of the ears is almost touching.

The other thing to note is that at a score of 0 under normal circumstances in a non-painful rabbit, the ears tend to stand up vertically, either facing the incoming sound. At a score of 1, the ears tend to be back at about a 45 degree angle relative to the back of the sides, and at a score of 2, we tend to see the ears that are held very close to the back or sides. And again if you look across this panel of pictures from left to right, you can clearly see this rabbit's ears are closing off, they're losing that dish shape appearance, and they're getting closer to the back of all sides of the rabbit.

This is just an alternative view, again to give you a little bit more experience when looking from different angles, and again you can clearly see if you go across the panel pictures from left to right, that this rabbit's ears are closing and getting closer to to the back and sides of the body. The final action unit is whisker position and whisker shape. This can be quite difficult to observe in an animal because often the whiskers are the same colour as the coat, which means that they can just disappear.

Particularly it's very hard to see in photographs. It is actually much easier to see with the naked eye. So under normal circumstances, a non-painful rabbit, most of its whiskers have got a relaxed, curved profile, and they're kind of facing all kinds of directions.

When in pain, most of the whiskers lose this relaxed, curved profile and become increasingly straight. The tension in the whisker pads increases, pushing those whiskers away from the face to stand on end, and the whiskers tend to clump together. And most of the whiskers no longer point in different directions, but now are increasingly pointing in the same direction.

At a score of 2, most of the whiskers tend to to point straight downwards. So again, if you look at this panel of pictures from left to right, you can. Clearly see the whiskers are changing from being facing all kinds of directions, being having gentle downward curve, to moving to becoming much straighter, losing that curved profile to standing away from the face with tension in those cheek in the whisker pads, and ultimately, at a score of 2, facing straight down in the same direction.

This is an alternative view of whisker position and shape just to give you some additional information. And again, if you look across the panel of pictures from left to right, you can clearly see this rabbit's whiskers are moving from being, having a curved profile and facing all kinds of directions to increasingly facing in the one direction, in this case straight down at a score of 2, being stiff and there being tension in those whisk components. So what general advice would I give you about using the rabbit grimmer scale, because this scale is still under development, so we're still refining it and we're still trying to make it a much more valid, efficient and effective, reliable method of assessing painting rabbits.

So at the moment, I would say if you were score of your rabbit, if you were scoring a rabbit. And your, your, your scores are for an action unit fall between two points, for example, between 1 and 2. So you're thinking, well, actually it's about a 1.5.

I would always, choose, I would always use a note of caution and go for the highest score. So if you've got a, if you're undecided between a score of 1 and 2, I would always go for the score of 2, the highest score. Again, when you're looking at these animals, if you think there's a difference between the left and right hand side of the face, again, go with the note of caution and choose the side of the face that has the higher of the two scores.

So for example here, if the left eye's got an orbital tightening score of 1 and the right eye has an orbital tightening score of 2, then I would choose to score the rabbit has an orbital tightening score of 2. Thirdly, if you cannot see the action unit, don't score it. Use the other action units instead.

I always argue that after being trained, it's, you either can see the action unit or you can't. If you're thinking, no, I can't see it, then simply don't score it. That's where the average action unit score for the total score comes in.

Other general advice, make sure you you're familiar with this scale as you should be for any pain assessment scale before using it. So study the posters that are available, the manuals that are available, have them on hand when you're doing the scoring so you can refer back to them. Practise, and make, make until you feel competent and confident in using these systems.

As we are using overall scores, so really what we're doing when we assess these animals is the total grimmer scores, either the cumulative adds together score or the average score. Small differences between people for individual action units are not that important. So if one person scores a rabbit.

Units as 0 and 1 scores it at 1, or somebody scores it at 1 and somebody has scores it of 2, I'm less worried about those individual subtle nuances in the in the individual scores action units because often the total score, it all comes out equal. However, we do need to worry about gross differences. These are an issue and really mean more training is needed.

So if somebody's scoring an action unit of 0 and somebody else is scoring an action unit of 2, we need to go back, we need to understand why they're differing, and we need to train them so that we get consistency. At the moment, what we don't have and what's most commonly asked for is an analgesic intervention score. So what score means that I have to give analgesia.

I am currently working on that at the moment and I'm hoping to have an answer to that in the next 6 months. In the meantime, the general rule of thumb is the higher the score, the more likely the animal is, is, is to be in pain. So at the moment, if you're seeing scores of 3 or more, then I think we can be fairly confident that the animal's likely to be in pain.

OK, so moving forward now, what I thought would be a good idea to do is to take you through a few photographs and for me to show you what I score them so that you get an idea, a practical idea of what we're scoring and how we would score it. So we're gonna show you, I'm gonna show you 3 photos of rabbits, and I'm gonna score each of the individual action units for those photos so that you can see what I. Score.

So this is our first rabbit. So what I would score here for orbital tightening, I would give this rabbit an orbital tightening score of 1. OK?

You can see that it's eyes, it's somewhere between 0 and 1, I would argue. It's not quite closed, but it's certainly not bright and open. So I would er err on the side of caution here and give this a score of 1.

I would also give the cheek flattening a score of one. Yes, you can see some definition to the cheek muscles, but I would argue that that face is not a zero, it's certainly not puffy and bulging. It's certainly there is some cheek flattening going on there.

In terms of nostril shape, I cannot clearly see the rabbit's nostrils, so as I said, I wouldn't score that at all. OK, I can't see it, therefore I'm not going to score it. In terms of ear position and ear shape, I'd give that a score of 2.

OK, the ears are back against the body and they are very tightly curled into a tight cylinder with the ear tip with the inside of the ears at the face almost touching. So I would definitely be giving that a score of 2. And the whiskers, I can clearly see here that I would give these a score of 2.

I can clearly see that these whiskers are all facing in the same direction. They are sticking away from the face and they're all facing straight down and stiff. Therefore, I would give that a score of 2.

I hope that's clear. Rabbit #2 OK, I would give its orbital tight and score a score of 0 because the eyes are wide open, they're nice and bright, therefore it's nothing more than a score of 0. In terms of cheek flattening, again, I would argue this rabbit has nice bulgy cheeks.

You can clearly see the delineated cheek, but you can see the muscles. I would be giving that a score of 02. I can't see the nostrils on this, black-nose rabbit, it's quite difficult.

I mean if I really pushed myself, I would probably give that a score of zero, but it's not clear as far as I can see. Ear position, again, I would give this a score of probably 0 because it's ears are nice and open. They're kind of up, they're not quite back at a 45 degree angle, and they're nice and open, though you could argue that the ear, the inside of the base of the ears is coming together, I still think they're fairly open and I would call that a zero.

Finally, at the whisker position in shape, the whiskers of this rabbit, if you look very closely, are facing in different directions. I can clearly see that some of them are curved, therefore again, I would give that a score of 0. And finally, rabbit number 3.

OK, I would give this guy an orbital tightening score of 2, its eyes are very clearly shut, they're over halfway closed and you can see that there's a, there's a subtle eye squeeze there, so that would definitely be a score of 2, as far as I can see. The cheek, the flattening score again would be a score of 2. This rabbit, you can clearly see that its cheeks are really flat, you can't really see any muscle definition, and it does have a sunken look to them.

So I would be scoring that as a score of 2. The nostril shape, we can see the nostril shape here because the black is actually on the top of the nostrils. You can clearly see here that there is that there is still a subtle U shape there, but I wouldn't argue it's a gentle U.

I think it's somewhere closer to its stiffening and going a bit more V shaped, and I'd be giving that scores 1. The ear position, the ears are laid, they're not laid straight on the back now, but they're laid closer to the side, and they're beginning to close off. And I'll be giving that score of 2.

Now this is a nice example where you would say the ear on the right hand side of the rabbit is probably a score of 1, but the ear on the left hand side of the rabbit is clearly a score of 2, yeah, that looks very cylindrical. Therefore, I would definitely be giving that score of 2 on that side. And finally, whisker position and whisker shape.

Again, if you look very carefully, the whiskers of this rabbit are stiffened and they are away from the face, and you can see a little bit of tension in the whisker pads, but they're not all facing in the same direction and they're not all facing straight down. Therefore, I'd be giving that a score one. I hope those examples will help you scoring roundbacks going forward.

If you have any questions, please do let me know. I'm always happy to help in terms of helping people become consistent and efficient with scoring. Right, so the finest final part of this presentation, I'm gonna focus very quickly on some evidence to show you that this scale is effective before moving on to the limitations of the scale which we need to be aware of, and things that we don't know about the scale quite yet and we're working on trying to understand.

So. The rabbit grimmer scale has been validated looking at post-surgical pain or post procedural pain in rabbits. This is an example of what we've studied we've done here at Newcastle, where we use the rabbit grimmer scale to score pain following routine castration and what.

You have in this figure on the Y axis, on the vertical axis, you've got the mean total score, and then you've got the different periods of which we scored the rabbits, from pre-surgery, pre-op, then 1 hour, 5 hours, 24, 48 hours post-surgery. We split these rabbits into two treatment groups. The first group got standard dose of routine non-steroid anti-inflammatory meloxicam, and the other group got a motor mogul.

Analgesia regime comprised of meloxicam and local anaesthetic, and you can see that from the figure. What you can clearly see here is that preoperatively are two preoperative time points that we get a mean score in either group of around 1. This illustrates to you that the scores are never zero at baseline or in a non-painful animal because you're always, you know, there may be subtle changes that you, you give scores of 14.

But generally only for one action unit. What we can also clearly see is that from pre-op to one hour post op, we get a very large over fourold increase in the total score, but that score is actually slightly lower in our multi-modal group. So what we've got here is our change from pre to post painful states, and that our analgesia regimes here are modulating that and reducing it in the case of the multimodal.

And then we can see here our scores reduce further 5, 24, 48 hours post op, which we would predict as the animal naturally heals. Now we can validate the rat or have validated the rabbit groomer scout against other means of assessing pain in rabbits that we use. So we use a behavioural based system as well, which is comprised of a variety of different behaviours including twitching, wincing, staggering, flinching, arching, quivering and shuffling.

And if you're interested in those behaviours, please do contact me. I'm quite happy to provide those as well, and I, I, my contact details at the end of this presentation. So what you can see here is now what you have on the vertical.

Y axis, we have the mean frequency of these behaviours which we consider to be pain related. And again, what you can clearly see here is that preoperatively, there are no behaviours seen in a 10 to 20 minute period. We get a significant increase, 76 to 7 fold increase in the rabbits.

1 hour post op again on multimodal analgesia is reducing that and then we see a reduction at 5, 24, and 48 hours. So what we're seeing here is the same pattern in our behavioural based and our grim scale based data. This suggests that both methods are measuring the same thing, i.e., pain.

Is the rabbit grimma scout accurate and reliable? Well, from our studies that we've done, it's accuracy is about 84%. We get a false positive at 6% and a false negative at 10%.

And that 10% false negative is the one that is most important, because if we, that's how often we miss animals that are in pain. The false positives are simply animals we think are in pain but aren't. So 10% is not bad, but we're working all the time to make that more accurate.

And this accuracy somewhat depends upon the type of variability you have. So if you're using images or you're doing it live, that kind of varies the accuracy. So the better the quality of the images or video or live scoring that you do, the more and the more that you are trained and the more confident confident you are with using the scale, that accuracy will go up.

We also know that this method is very reliable, both within observers looking at animals, looking at different animals and between observers looking at the same animal. It has a very high interclass correlation of 0.91 out of 1, so an interclass correlation is simply a measure of the reliability.

So it's a very reliable method. We have a lot of consistency within us, within and between our scores. Finally, we should be aware of the current limitations of this technique.

So, the first and most important limitation is that it should only be used in awake animals, OK? If your animals are falling asleep, asleep or waking up, you're going to get false positives. You're going to think the animal's in pain when in reality it might not.

Therefore, animals that are under the effects of sedation and anaesthesia, shouldn't be assessed using this method because the sedation and anaesthesia are gonna have a confounding effect. They're gonna make you think the animal's in pain but it's not. So if you're going to use this scale for post procedural or post-surgical pain, you need to make sure that your animals are clear of the major effects of sedation and anaesthesia before you use this method.

This method has been developed for assessing acute pain or acute episodes of pain, not chronic pain in itself. It's still most effective when you have a non-painful score for that animal, so a baseline score. To compare your post procedure, post-surgical or an animal in pain score again.

We can do it without that baseline score, but if you can get that baseline score, that's always more accurate at the moment at least. As I said, we don't have an intervention score, an analgesic intervention score currently for this, but in the meantime, if you see scores of 3 or more, then I think it's likely that your rabbit is in pain. And finally the things that we don't know yet about the scale that we're investigating at the moment to try and get answers to.

We know from other grimmer scales in other species that the breed or strain of the animal and the sex of the animal can influence the score you get, so they can differ in magnitude between males and females in different breeds, and that comes from the mouse score. We know that as I said and as I alluded to in the previous slide, that anaesthesia and analgesia can have an effect on the animal if the animals are not clear of the major effects of the anaesthesia or sedation if your if your analgesia has a sedative asthma. We know that the presence and the sex of the observers might also influence the grimace scale.

So if you are stood there watching your animal and we know from rat and mouse grimer scales that if you are male, that can actually cause the grimmer scale to be attenuated, so the animals might be more likely to hide their pain. We also know that we also suspect that these scales aren't pain specific, that they may also be sensitive to other negative or negative states such as fear and anxiety as well as pain. This evidence currently comes from mice.

So I would argue at the moment. The actual units that most of our grimace scales, including the ramic grimer scale, are more likely to be pain related rather than pain specific. That doesn't actually matter in practise so much because it gives you an indication of something up with the animal.

And often pain does not come without fear and anxiety. One general thing that I want to point out to you when assessing pain in rabbits is rabbits are very likely to to mask their pain, particularly if they don't know you. So what we have here are two videos.

The left hand video is a video of a rabbit being observed with the observer present, me, and the right hand video is a rabbit being observed post-ovar hysterectomy, about 3 hours. Both videos of the same time point in these two rabbits, 3 hours post ovarary hysterectomy when I'm not present. And as you can clearly see, these rabbits are behaving very differently.

The presence of my, of me, the observer here is really making this animal hide many of its reactions. So to conclude, how do we maximise the assessment of pain in rabbits? Well, we use a combination of indices, OK, we don't just use the grimmer scale, we add the grimmer scale to the methods we're already using because all methods have their limitations.

But often what we find is that one index, the limitation in one index can be compensated by the, by the, the strength of another index. I suggest that you're familiar with lots of different methods of assessing pain, you're familiar with how the species or breed may affect that assessment. Always be, try to be familiar with what normal looks like, i.e.

The animal in a non-painful state. And finally, please be aware of the learning effect. When we use these scales and the more we use them, the better we get, OK?

So the better we get, so what I would suggest is that you practise using them and practise and practise and practise so you get to a point to where you're getting consistent scores all the time. And it's at that point that you go out and use the clinic. Well, I hope that this webinar has been useful and has given you some much deeper understanding of the rabbit Grimmer scale, what underlies it, and how you actually carry it out.

If you do have any questions or you want to discuss anything about assessing pain in rabbits, then please feel free to email me at Newcastle at this email address. Thank you very much for listening and I hope you found this interesting and valuable.