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A vet visits a Delhi slum: day one – an introduction to street dogs and rabies

[caption id="attachment_3735" align="aligncenter" width="768"]street_dog_2 Street dogs are part of the urban ecosystem in India[/caption] I'm just a vet in small animal practice in Ireland, but for the next week, I'm going right out of my comfort zone: I am travelling to Delhi, to visit a slum, where I'll be taking a look at the issue of street dogs and rabies. Rabies is one of those diseases that just flits across the consciousness of most of us: we know it's a terrible disease, and we feel blessed that it doesn't exist in the UK and Ireland, but that's about as far as it goes. The truth is that for many people and animals, it's a daily curse.  Minor dog bites are common all over the world, especially in children. Most often minor first aid is all that's needed: rarely, a visit to the doctor may be called for. Yet in most countries of the world, the threat of rabies in an additional worry. If a child happens to live in India, that minor dog bite could have had desperately serious consequences. If he was lucky, he might be taken to a doctor to be given post-exposure anti-rabies vaccination. However, it'd be far more likely that this level of medical intervention would be unavailable to him. Nothing would be done other than basic cleaning of the wound. If the dog was carrying rabies, he would be infected, and in the following weeks, he would develop symptoms of rabies. He might have a fever or a headache at first, with an itching sensation at the site of bite. A few days later, he would develop anxiety, confusion and agitation. As the disease progressed, he would develop abnormal behaviour (such as fear of water), hallucinations, and insomnia. He would go on to suffer a terrifying death. The most shocking aspect of rabies is that it is completely preventable. Vaccination of dogs in bulk programmes is inexpensive and highly effective: it can cost as little as 50c per dog. In comparison,the cost of a human being treated for rabies after a dog bite is around €40, which is over a month's salary in the regions where rabies is common. The World Health Organisation believes that mass canine vaccination programmes are the most effective measure for controlling rabies, and that vaccinating 70% of the dogs in an area where rabies is prevalent is necessary to control the disease in both humans and dogs. Targets are in place to have rabies eliminated from the planet by 2030 but this won't happen unless we all start paying more attention to achieving this goal In the recent past, mass dog vaccination programmes have allowed some countries to become rabies-free: there are many examples in South America. In Sri Lanka, this type of programme has reduced rabies deaths from more than 350 in 1973 to just 50 in 2010. Yet in over 150 countries around the world, death by rabies continues to be a threat to humans and dogs. Over 60 000 people die of rabies every year, with over 95% of them in Asia and Africa. India is the country with the biggest rabies problem, with over 20000 people dying every year. So-called "street dogs" are part of the urban culture. They play an important role in the ecosystem by helping to deal with garbage: in areas where dogs have been forcibly removed, the local rat population has boomed, with bubonic plague then becoming a major public health problem. But street dogs also carry rabies. The size and scale of India makes this problem seem impossible to solve: it's the second most populous country in the world, with over 1.2 billion people (nearly 300 times the population of Ireland, or 20 times the UK). Despite the magnitude of the challenge, the answer is still simple: vaccination of 70% of street dogs against rabies, combined where possible, with sterilisation of dogs to prevent breeding. If you think of another comparison: 20000 people dying of rabies every year is the equivalent of  67 people dying in Ireland, or 1000 people dying in the UK. Can you imagine the public outcry if that was to happen? Why should we be any less outraged because the people dying happen to live in India? I'm being hosted in Delhi by a charity called ASHA, which is primarily focussed on human health and education in the slums.  I have persuaded them to help me to investigate the severity of the rabies and street dog issue in one of their slums, and they are providing me with an interpreter to carry out a questionnaire. And the kind and passionate people at Mission Rabies have drafted a questionnaire for me to use.  In the space of ten days, I am not going to make much of a difference to anything, except perhaps to my own understanding of the issue, and my own desire to do something about it. If you read this blog for the next while, perhaps you'll learn a bit too. Rabies isn't going to go away by itself: it will take the joint effort of many people with a wide range of skills from a variety of backgrounds. Could you be one of them? street_dog_6
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So You Want To Be A Vet? – Getting into vet school and beyond

I did and I still do! Being a vet is a brilliant job; every day is different. I get to work with great people and use the skills I worked hard to gain to help animals and solve their problems. However, it is also involves long hours, regular challenges, with both pets and people, and it can be very stressful. The first hurdle to being a vet is actually getting into vet school and with an average of nine applicants for every place, it is one of the most competitive university courses there is. The standard of students is always extremely high and I know the selectors face a very difficult task in picking out those best suited for a career in veterinary medicine. First and foremost, you must get the right grades at both GCSE and A Level. Without these you won’t even be considered and rightly so; academically the vet course is tough. However, as well as being a geek (!), you also need to have excellent people skills, good practical skills and, I believe, bags of common sense. You can help to show you have these by ensuring your extracurricular activities are relevant and varied; music, sports, volunteering and Duke of Edinburgh all regularly appear on successful candidates applications. The other vital piece of the puzzle is completing a diverse range of work experience to demonstrate you really understand the veterinary industry. Trust me, it’s not all cuddling cute animals! The most obvious place to start is in a vet clinic but this can be difficult. Most practices receive a large number of requests but do persevere. You should also spend some time on farms getting your hands dirty. Helping out at milking time and lambing is not glamorous but will be rewarding & very useful. To stand out from the crowd you could also consider seeing other aspects of veterinary work such as zoos and exotic pets, abattoirs (all of which need a vet on the premises while they are operating) and scientific laboratories. Many vets are involved in research and during the course you will spend quite a bit of time in the lab! Wanting to be a vet for most people is a passion and very few probably give much thought to what working as a vet is actually like. It is a cliche to say it is more a way of life than a job but veterinary is certainly not 9-5! Many positions will include on call, meaning you will be working in the night and often the next day as well. A great deal of veterinary medicine, particularly for the farm and horse vets, is done alone, which can be stressful and even the small animal vets in a clinic will be expected to make their own decisions from day one and perform surgery single handedly. This is difficult when you first start and although it gets easier, it is always a challenge! It is also important to consider the salary you are likely to earn. This is often something students don’t consider important but it soon becomes so when you have a mortgage to pay and a family to support! As a vet you will always be paid a good wage but it is very much less than similarly qualified professionals. Trust me, you soon get tired of clients thinking you earn as much as a doctor when it is more likely to be a third of that! Being a vet is wonderful and I feel very fortunate to be in my dream job. However, I confess when I set my heart on it I gave very little thought to the practicalities of life with long hours, on-call, demanding owners and difficult cases. Although, to be honest, even if I had it wouldn’t have changed my mind! If you are sure you want to be a vet; have the drive, intelligence and I haven’t put you off (!), then my advice is work hard, go for it and maybe one day, I’ll see you in theatre! Cat Henstridge BVSc MRCVS - Read more of her blogs at catthevet.com
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High graduate debt, falling demand for pet health care & corporatisation. The veterinary profession is changing: is it for better or worse?

There's a lot of debate going on right now about the future of the veterinary profession. Many vets are worried about the current trend which basically follows this path:

1) Huge demand to study veterinary, especially among young females (80% vet students are female)

2) Not enough places at vet schools: traditionally, the number of student places has been capped in order to avoid flooding the market with far more vets than jobs

3) The realisation by universities that there's money to be made in teaching vet students, and that there's a strong demand from students who don't make it into the established vet schools. The first new vet school in over 50 years opened recently in the UK, and at least one more is planned. Meanwhile, in Eastern Europe, veterinary courses are taught in English, offering entry to the vet profession with a lower academic barrier if students are prepared to pay the fees

4) This is linked to the rising cost of veterinary education, with students in England paying £9000 per year x 5 years plus living costs

5) The result is that new vet graduates are qualifying with large debts, in higher numbers than ever before

6) Meanwhile the veterinary market is contracting, with people spending less money on pets, and so there are fewer jobs for vets available

7) Result: increasing numbers of underemployed young female vets with large debts

8.) Next part of jigsaw: there are fewer young vets to buy into established vet partnerships, and an increasing trend for chains of vet clinics to go "corporate", owned by shareholders whose main aim may be profit rather than the traditional broader professional view of a vet fulfilling a calling to earn a living

9) Result: vets become pawns in the animal care field, with young female vets desperate to pay back loans by working for corporations. As employees rather than part owners, they become subject to pressures common in other walks of life ("For your bonus, you need to sell so much food, book in so many dentals, see so many people every hour")

10) The long term potential result: erosion of trust in vets as pet owners question whether something is recommended because it is really needed, or because the vet needs to reach a target. This erosion of trust has already begun in recent years, with consumers questioning everything that professionals do: the sequence that I've outlined above will exacerbate this trend.

This trend in the veterinary professions seems to be a global one, and as ever, the USA seems to be further down the path than the rest of us. An excellent article has just been published on this in the New York Times - read it here: http://www.nytimes.com/2013/02/24/business/high-debt-and-falling-demand-trap-new-veterinarians.html?pagewanted=all&_r=2&

Vets are worried about these changes: our profession is heading down a new path with unpredictable consequences. It's hard to know what can be done to change the path: it feels like we're being nudged this way by unstoppable market forces.

What do you think? Should anything be done? Or do we just need to accept that this is the way it's going?

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The Kinder Cut – Castration of horses

This is the time of year when people start to look at their cute little foals, and suddenly realise they're starting to grow up fast... As a result, it’s also when we start to get phone calls from people to talk about gelding them. If you are considering getting a colt gelded ("cut"), my advice would be to contact your vet, who will be able to advise you on the best approach in your particlar circumstances. However, I'm going to try and go through some of the commoner questions below, so you've got some basic information on the decisions to be made, the procedure, and what you'll need to consider. The first question, of course, is whether or not to get him cut. It’s an important decision, so these are my thoughts... The majority of male horses are castrated, and for very good reason - very few people have the facilities, the time, or the inclination to manage an entire stallion. The old adage had it absolutely right - "You can tell a gelding, you can ask a mare, but you discuss the matter with a stallion". Although there are some superbly well mannered stallions out there, it takes years of expert training - and in my experience they're almost always more "bolshie" than a gelding, and much less forgiving of any mistakes. They are also much more easily distracted (e.g. by a passing mare), and prone to fighting. Does this mean you can't train them well and keep them happily and healthily? No, of course not - but it’s a lot harder. The majority of stallions can't be kept in groups because of the husbandry regimes on most yards, so have to live on their own. That's not good for their mental health, or their owners and riders! If someone has the knowledge and facilities to bring up a stallion, I don't have a problem with that, and I wish them luck, but I've seen too many bored, frustrated and borderline dangerous stallions who haven't been brought up correctly, and remain a liability. Geldings, however, can be kept in groups, can mix with other horses, and are less likely to lose the plot or throw a temper tantrum. They also don't present you with unexpected foals in your competing mares... If you decide not to have him done, you need to be sure that you're doing it for the right reasons. The majority of horses are not necessarily good breeding material - you need to take an objective look at him and decide if breeding from him is actually going to benefit the breed. If you're avoiding doing it just because you don't like the thought of the procedure, you'll need to think long and hard about whether thats in his best interest - or yours. If you are getting your colt cut, the next decision is when to do it. There are two major concerns - the time of year, and the maturity of the colt. In terms of time of year, it’s best to do it when the weather is cold enough to prevent flies from infecting surgical wounds. Ideally, then, this would be in late autumn or early spring, but gelding him in winter is perfectly acceptable if the facilities are suitable. Regarding the colt's maturity, there is an upper and a lower limit. The lower limit is the most rigid - except in an emergency (e.g. a strangulating hernia), I would never geld a colt until both testes had descended into the scrotum - because it’s really important to make sure you've got both! This usually happens between 6 and 12 months old, but it is a bit variable. In addition, the colt has to be strong and mature enough to survive the surgery, although with modern anaesthetics this isn't as much of an issue as it used to be. The upper limit is much more flexible. Stallions into their twenties are castrated fairly commonly, but once they've passed through puberty, a lot of the stallionish behaviour is learnt, and won't be reversed by castration, including some forms of aggression, and mounting behaviour. Sometimes, people like to wait until a colt is 3 or 4 years old before gelding, but I think that often even that is too late - although it does allow the colt to develop more muscle, he'll also be developing stallion traits. In addition, the younger the colt, the smaller the testicles, and the smaller the testicles, the lower the risk of bleeding during the op. During puberty, the testicles increase dramatically in size, and as a result, their blood supply increases accordingly; the bigger spermatic artery in a post-pubescent colt is much harder to control bleeding from. As a general rule (and it’s a VERY rough rule of thumb!) I'd normally look to geld between a year and eighteen months old. That said, there are a lot of exceptions - I once had to sort out the castration of a four month old colt because he'd started mounting his mother... There are also a number of opinions about weaning - before, after or at the same time? In this case, I think it depends entirely on the colt in question, and it’s an area (one of many) where I'll usually defer to the owner's judgement. Before you go any further, its a good idea to get the colt thoroughly checked out - both testicles need to be present and easily palpable; if one is "shy" and difficult to find, I usually recommend checking again in a month or so. If it’s still inaccessible, the colt may be a cryptorchid (i.e. a rig, with one undescended testis). These colts should ALWAYS be castrated, and have to be done under general anaesthetic, if possible in a clinic. This is because the retained testicle, being kept at an abnormally high temperature inside the body, is more likely to become cancerous. Also, the defect may be genetic - and if so, he'll risk passing it on to his offspring. Once you've decided when, there's another important decision you and your vet will have to make, and that's the details of the procedure. Basically, there are two factors to decide - firstly, do you want him done "at home or away"? Secondly (a related point), do you do him under standing sedation or down under a general anaesthetic? Regarding the location, it depends on your practice's policy and facilities. Many practices now offer castration at the clinic, but the majority of people still choose to have the op done at home. The advantage of having it done at a clinic is that the procedure can be cleaner, and all the equipment and apparatus is there; in addition, many practices charge a callout fee for coming to the yard. However, that's offset by the fact that you'll have to transport the colt to the clinic; in addition, I think it’s usually less stressful for the procedure to be done at home, assuming the appropriate facilities are available. Exactly what facilities you need depend on the technique that's going to be used. There's a lot of debate as to this decision, and some frankly ridiculous comments from some badly-informed people out there. I'm going to talk through the options and the pros and cons. The two main options that you'll need to think about for the procedure itself are whether to have the op done under standing sedation or general anaesthetic. In some cases, the decision is easy - miniature horses and small shetlands should almost never be done standing, because they're too small for the surgeon to get good access and control the site, for example. Draft breeds are at a higher risk of eventration (see below, when abdominal contents escape through the castration wound), and so need a different surgical technique, which may be easier under a general; and fully adult stallions bleed more so may need better surgical access - again, a general anaesthetic makes this easier. However, most colts can be done either way, so you and the vet need to decide which you prefer. Under standing sedation, the colt is given intravenous sedatives (see my blog on sedatives) so he becomes very dopey. He will continue standing up, but his head will drop, and he is likely to adopt a wide-based stance (which makes surgical access easier!). However, its important to remember that he is still to some extent aware of what's going on, so local anaesthetic is injected into the testicles (perhaps 20ml into each one, plus some under the skin of the scrotum) or into the spermatic cord (although I find that that's easier said than done, with most colts pulling the testicles up tight to the body wall so the cord is difficult to access from outside) to numb the area. The castration is then performed with the vet working from standing beside the horse. This approach avoids the risk of a general anaesthetic, and means the horse will recover from the sedative faster. However, the degree of sedation achieved is variable, and some colts appear to be more aware of the procedure than one would like, no matter how much sedative you pour into them. There's also a MUCH higher risk of the vet or their assistants being injured - unsurprisingly, some colts object violently if they realise what you're doing... In addition, the surgical access is poorer (the vet is having to work upside down, and largely by feel) so if there is a complication, it is harder to control it. Under a general anaesthetic approach, the colt is sedated and then given an injection of a general anaesthetic. He'll become very sleepy, and then lie down. Once he's out, an assistant lifts up the top leg, giving the surgeon access. The disadvantage is that most vets will only do a GA on a horse if there's another vet along to monitor the anaesthetic, which may affect the cost. In addition, a GA is a risk in its own right - one study suggested that the average mortality rate from GA in a horse is 1% (although this includes colics and emergency operations - the risk for a young, healthy colt is much lower). On the other hand, the risk of injury to the vet or assistants is much lower, and the risk of surgical complications is also much reduced, as the surgeon can see exactly what they're doing. Is either one definitively better than the other? No. However, it is a decision to take WITH your vet, as they may have a preference that will affect their efficiency. For what its worth, I've done geldings both ways, and personally I prefer to do them under general, because its safer for me and everyone else around - and if there was to be a complication, I've got a better chance of finding and fixing it at the time. The procedure itself is pretty much the same whichever way up the horse is. Along with sedation, I give an injection of an anti-inflammatory and painkiller, and antibiotic cover (no procedure done on a yard or in a field can ever be truly sterile, so I'd prefer to make sure there are antibiotics on board when we start). In the past, vets didn't routinely give painkillers as well as the sedation (which contains a painkilling component), but personally I don't think its fair not to. There has historically been quite a mystique about the procedure itself - probably because people are a bit shy to discuss it. As a result, there is sometimes serious confusion - remember, gelding is NOT the same as a vasectomy, and it can't be reversed... Not even (as apparently happened to a colleague of mine) if the client stops you as you're about to drive off and, holding up a neatly severed pair of testicles, asks the vet to reattach them because she's changed her mind... So, here's a quick run through the procedure: The area of the groin is scrubbed with a skin disinfectant, and a final check is made that both testes are accessible. Whichever one is held closer to the body is the one I'll start with, just in case it is retracted later. I'll then scrub up so my hands are sterile. Some vets wear gloves, others don't - I don't think it really matters as long as they've scrubbed thoroughly. Gloves add an additional sterile barrier; but on the other hand they can reduce your feel and grip, so it depends on what the vet is happiest with. Once the scrotal area is scrubbed, the vet will use a scalpel blade to cut through the skin of the scrotum. There are a couple of different options from here on, but the principle is the same; to cut down through the tissue to the vaginal tunic (the membranes that surround the testis itself) and then gently pull the testicle down and out. In an "open" castration, the tunic will be opened, in a "closed" technique, it gets left intact and the testicle pulled down still inside. Once there's enough slack in the spermatic cord (containing the blood vessels, nerves etc that supply the testicle), the emasculators are applied across the cord, with or without the tunic, depending on the technique. These are a clever bit of kit that crush the cord, preventing it from bleeding, while at the same time cutting off the testicle itself. (Quick aside here - I was doing a gelding once and, as is customary, I showed the removed testicle to the owner to show it had been done; he was a teenage lad and he fainted dead away. Interesting ethical problem there - do I try and help the unconscious boy, or do I just keep working on the anaesthatised horse who'll soon wake up? Fortunately, he recovered on his own before I had to scrub out, but he was pretty green around the gills for the rest of the morning...) In an older stallion, most vets will put a suture through the cord to ligate the artery, but this increases the risk of infection, so we don't always put one in if doing an Open procedure. After removing the emasculators, the vet will check closely for bleeding from the stump. If there isn't any, they'll repeat the procedure on the other side. If the surgery is taking place in the field, the vet will usually leave the incision open for drainage; closing it seriously increases the risk of post op swelling and infection. As a note, there is always a bit of bleeding after the operation. The rule of thumb is, if you can count the drops, its fine! There's also invariably some swelling of the sheath, but again, it isn't usually anything to worry about. If in any doubt though, you should contact your vet. Your vet will give you instructions for post op care, but the most important thing is to keep the new gelding moving, to reduce the swelling and encourage drainage. The complications to be aware of are bleeding, eventration, and infection. bleeding is pretty obvious - some oozing from around the incision is normal, but there shouldn't be any significant haemorrhage from the stump of the spermatic cord. If there is, or if there's a lot of blood - call your vet! Uncontrolled bleeding is an emergency that may require a repeat surgery to control it. eventration, is when abdominal contents prolapse through the inguinal canal, and it’s more common in draft breeds. This is the main reason we'd do a Closed castration, as it ties off the tunic; but it does increase the risk of infection. Eventration usually involves some fatty tissue (the omentum) and although it needs urgent surgical repair, it isn't usually life threatening. Very occasionally, however, it progresses to evisceration, where loops of intestine come through. This is very serious, but (touch wood) it’s also very rare. infection is uncommon, and usually responds to antibiotics. In a few unlucky cases, though, a schirrous cord forms, where abscesses form in the canal. These take months of management, and in the end, treatment is usually surgical removal of the infected tissue. These complications are very rare, and even if they occur, they're usually fixable, so don't get scared of the possibility! I only mention them so you've got an idea of what to look out for. The last thing to bear in mind is that the gelding may still show sexual interest for some weeks after castration (at least, if he was before), and may even be fertile for a time: although he can't make more sperm without testicular tissue, there will still be some "in storage" in the spermatic ducts. I always advise that a newly gelded colt or stallion should be isolated from mares for at least 6 weeks, after which any remaining sperm will have died or been flushed out, and his testosterone levels will have declined to the point where he won't have any hormonal urges. The bottom line is this: although it doesn't seem a nice thing to do, for most colts in most situations, gelding leaves them happier and more content than they would otherwise be as entire stallions.
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Sedatives and Sedation in Horses

We routinely sedate horses in practice - after vaccination, it’s probably the most common "routine" job that we do. So, what are we doing? How do the drugs work - and why doesn't it always happen the same way? "Sedation - a state of rest or sleep... produced by a sedative drug." That's the dictionary definition, and it makes it sound lovely and simple - give a drug, and the patient goes to sleep. Of course, in reality (as usual with anything equine!) life isn't that easy... For those who haven't seen it before, a sedated horse doesn't lie down, but their head gets lower and lower, and they may require something to lean on to help them balance. It’s also important to remember that a sedated horse CAN still kick - they're just much less likely to do so! It often seems that the horse is still more or less aware of what's going on around them, but they're too sleepy to care about it. As a result, we'd almost invariably use pain relief and local anaesthetic as well if we're carrying out a surgical procedure. There are a wide range of situations in which we like to use sedation. Generally, it’s to make the horse more amenable when something nasty or scary is being done to them. Of course, this varies from horse to horse. There are quite a lot of horses out there that need a sedative before the farrier can trim their feet; and there are others that will allow you to suture up a wound without sedation or even local anaesthetic (not recommended, but occasionally necessary). Probably the most common reasons we sedate horses for are... 1) Stitching up wounds, to stop the horse wriggling! 2) Tooth rasping, especially when using power rasps and dremels 3) Some surgical operations - for example, many vets prefer to castrate colts under standing sedation, rather than a general anaesthetic. This is because sedation is much safer than a general anaesthetic... On the other hand, the surgery is easier and safer (for the vet, as well as the horse) if the patient is completely "out", so it comes down to the type of horse and the preference of the vet doing the op. It’s important to remember that all sedatives temporarily alter the way the horse's brain and body works, and have a serious impact on the heart and circulatory system. As a result, they're all prescription-only medicines, and your vet will want to satisfy themselves that the patient doesn't have any underlying heart problems etc before using them. Overdose of a sedative is rarely fatal in a healthy horse, but it can still be dangerous, especially if there is any underlying illness that makes them less good at maintaining their blood pressure. Its also vitally important to tell your vet the horse's whole medical history if you're asking them to give a sedative - there have been cases of horses who were being treated with a (very safe) antibiotic (TMPS); the owner forgot to tell a vet this, and the combination of sedative and this antibiotic has resulted in a heart attack (technically, a fatal arrhythmia). There are three routes by which we normally give sedation: 1) By syringe or in feed. This is the slowest, least powerful and least reliable way to sedate a horse, but it has two advantages - you don't need a vet to come and do it, and you don't need to get so close to the horse to give it. The drug most commonly used is ACP, sold as Sedalin or Relaquin paste. Occasionally ACP tablets are used, although there are strict restrictions on when a vet is allowed to prescribe tablets instead of paste. There is a newer drug now available as a syringe, detomidine (sold as Domosedan gel), which is absorbed across the membranes in the mouth so shouldn't usually be given with food, but does work faster and give better sedation than ACP. 2) By injection into the muscle. Many injectable sedatives can be given into the muscle - this injection is more reliable than by mouth, but requires much higher doses than if given into the vein (in my experience, you need 4-5 times as much, and it takes about twice as long to work). It’s only usually needed if the horse is too wild or dangerous to get a vein, but it’s quite useful to "take the edge off", and then I can top up with intravenous sedatives if needed. The other situation where I've occasionally used it is when a severely colicing horse has to take a long ride in a box to get to a surgical centre. In these cases, I have sometimes given the driver a preloaded syringe so that if he horse freaks out or goes crazy in transit, they can give it something to calm it down and relieve the pain until they arrive. 3) By intravenous injection. Intravenous sedation is by far the best option if possible - it works fast (usually 5-10 minutes), you need lower doses, and you get much better sedation than by any other route. This is what I'll be concentrating on below. There are three "families" of drugs used to sedate horses: Acepromazine (ACP). This is a very "dirty" drug, in that it affects a wide range of body systems. It can only produce mild to moderate sedation on its own, and the effects are very variable between horses. It’s important to remember that once sedation has been achieved; increasing the dose WON'T result in deeper sedation, just more side effects. It also has no painkilling properties. There are two side effects in particular that we as vets watch out for with ACP. Firstly, it can lead to significant drop in blood pressure, because it makes peripheral blood vessels dilate (this is why it’s sometimes used in laminitis). The second effect is much more interesting - ACP is a mild muscle relacant of some muscle types, so it can be useful in azoturia and choke. There's one exception though (male readers of a senstive disposition, look away now...): ACP is a very powerful relaxant for the retractor penis muscle. This is the muscle that holds the penis in the sheath, and even low doses of ACP usually lead to male horses "dropping" the penis. This can be useful, but unfortunately in some horses (especially stallions, with a larger and heavier penis than most geldings); the paralysis of the penis can be quite prolonged, which can result in penile trauma. In extreme cases, this can be permanent or lead to gangrene, requiring amputation. Bottom line - if at all possible, avoid using ACP in stallions and entire colts! ACP does, however, have a place in sedation - when mixed with other drugs, it often prolongs sedation and means that the doses of each part of the combination can be dropped, reducing the risk of side effects. A quick note on ACP tablets - under the current Veterinary Medicines Cascade laws, it is illegal to use ACP tablets instead of paste in horses unless the vet has a clinical reason (unfortunately, price isn't considered good enough) to think that they are more appropriate. As a result, if your vet refuses to give you the tablets, they're not trying to rip you off - they're just obeying the law. Opiates Although opiates on their own are only very weak sedatives in horses, when combined with other drugs they lead to much deeper and smoother sedation than any other drug on its own. The drug usually used is butorphanol, which is a synthetic opiate (it’s a mu/kappa agonist/antagonist related to buprenorphine, for anyone interested) that has a fairly good painkilling effect as well as potentiating sedation from other drugs. Fortunately, it also has very few side effects, although its worth bearing in mind that any other opiates (e.g. Pethidine or Fentanyl) that the horse is given up to about 8 hours later won't work quite like they're supposed to, as the butorphanol will partially block their activity. Alpha-2 Drugs These really are the mainstay of sedation in horses (and in dogs and cats, for that matter). Alpha-2 drugs act by tricking the body into thinking it's produced too much adrenaline, so it stops releasing it, resulting in reliable deep sedation. They're also pretty powerful painkillers. There are three drugs that are commonly used, with slightly different properties. Detomidine and Romifidine are both fairly long acting drugs (30-40 minutes after i/v use), and when mixed with butorphanol are the standard sedative preparation for intravenous use, or on their own into the muscle. Detomidine is also available in a syringe for oral use. The third drug is xylaxine; this is a bit different in that it gives milder sedation, and only lasts 20 minutes or so. It’s particularly useful for sedating horses for nerve blocks etc, where in half an hour they need to be completely recovered and able to trot up. Before I sedate a horse, I always have a good listen to the horse's heart, and check its pulse and colour to make sure its cardiovasclar system is healthy. I'll then double check it’s not on any medication, and then give i/v sedation. I like to use either detomidine or romifidine mixed with butorphanol for routine sedation - I personally prefer detomidine, but that’s probably just because it’s what I "grew up" as a vet using! For longer lasting procedures, or if I want muscle relaxation (especially for dentals where I want the tongue nice and floppy!), I add ACP into the mix. Dosage is incredibly variable between horses and experience and judgement is more important than all the book learning available. As a rule of thumb, the bigger the horse, the less sedative per kilo of body weight it needs (so Shetlands often need as much as a light hunter). In addition, it depends on temperament - the more highly strung or excited, the more sedatives are needed. The other thing to remember is that apparently identical horses, in the same circumstances, may react very differently - the dose that will have Alf so deep his head's on the floor will have Brutus untouched, while Charlie is in the "Goldilocks" zone where he's just right. Of course, it also depends how deep the sedation you want - although personally, I've found that if you aim for "light sedation" to start with, you usually end up having to top the horse up halfway through. Once the injection's been given, it is VITAL to give the horse time for it to work in a quiet, dim, calm place. If the horse gets excited while you're waiting for the sedative to kick in, it won't work well. This is doubly true for oral sedatives, but it applies to injections as well. During the procedure, its sometimes necessary to top up, which is fine - the great thing about the drugs we use is that they work fast enough i/v that you can monitor their effects more or less in real time. Recovery is usually rapid and uncomplicated, although it’s important not to let the horse eat anything until it’s completely woken up, or it may choke. Very occasionally, I've had a horse that refused to wake up, or went too deep. After my first one, I took to carrying the antidote (Atipamezole, aka Antisedan or Sedistop) with me when I sedated sick or old horses. It's very expensive, but it works within a minute or two to reverse the effect of alpha-2 drugs - and once they're reversed, the horse wakes up incredibly fast! In practice, sedating horses is as much an art as a science, and there's rarely one "right answer" - it depends on the horse, the circumstances, and what you're trying to achieve. The main purpose is to allow us to treat your horse effectively and humanely. If you are worried about any problems with your horse or pony, please talk to your vet or try our Interactive Equine Symptom Guide to help decide what to do next.
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