We've been on quite a journey through this discussion of normal equine health and optimal care, safety, and welfare. In this final lesson, we'll highlight a few conditions that will reinforce the idea that knowing a bit about horse anatomy, physiology, vital signs, husbandry, and preventative care can help you address a problem in a timely manner before it turns into a life threatening crisis. By the end of the lesson, you'll be able to communicate with your veterinarian to act effectively on behalf of your horse, and list the signs of several conditions. Let's start with a common infectious disease like equine influenza. When we see a case of equine influenza, also known as flu, we'll likely hear a history that the horse was recently exposed at a horse show or a group equine gathering to a group of unfamiliar horses. The horse can be lethargic, often with a poor or no appetite, head hanging low, and there's often a cough and clear nasal discharge. Respiratory rate and pulse rate may be elevated. The horse may have a fever as high as 106. He may have increased capillary refill time and be dehydrated, with decreased manure and urine production. Some cases are mild and the horse recovers in a few days with minimal supportive care. However, with a persistent high fever and lack of appetite, the horse may get a secondary bacterial infection in the lungs or suffer a digestive upset or constipation due to the lack of food and water intake. Treatment by the veterinarian will likely include fluid support, either intravenous or oral fluids, to keep the horse hydrated, as well as antiinflammatories to control fever, plus or minus antibiotics to treat a secondary bacterial infection. Any time a horse is off feed or running a temperature greater than 102, it is recommended that you consult with a veterinarian. Despite our best efforts to keep the barn yard clean from debris and safe for our horses, horses always seem to find the one nail in their environment to step on. Believe it or not, a nail puncture to the horse's foot can be a life threatening event as their coffin joint is just centimeters away from the ground. Often, the nail will puncture the sole of the hoof and carry bacteria into the inner sensitive tissues of the hoof and inoculate them with that bacteria. You may notice your horse is standing oddly, perhaps only putting weight on the tip of the toe, or not bearing any weight at all. When you inspect the hoof, as you would if you were picking it out, you may see the nail still embedded. And sometimes, it is actually flush with the frog. So for example, you might only see the nail head or meet some resistance on your hoof pick when you go to pick. In most cases, when the horse steps on the nail, they may be mildly sore for a few days and get better. However, because the nail introduces bacteria into the sensitive tissue, it is not uncommon for a horse with a sole puncture to progress to a foot abscess a few days later, when the bacteria and pus are trapped inside the hoof capsule that does not expand. The horse will show very significant pain, often limping to non-weight bearing, and it can look like a broken leg. A foot abscess is the most common reason for a horse to show severe lames at the walk, without any other swelling on the limb. Any time a horse steps on a nail, it is wise to take a picture of that area and forward it to your veterinarian and check in. Depending on where the nail enters the foot, the level of concern will go up. If possible, try not to remove the nail until the veterinarian gets there. It is important that your horse is up-to-date on their tetanus vaccination for instances where they do sustain puncture wounds to the foot or other parts of the body. If your veterinarian comes out to inspect a nail puncture, the veterinarian will clean the puncture area and work to drain the abscess and give you details, after care instructions that involve keeping the foot clean. Remember, a common injury such as this can be life threatening if the nail enters a part of the foot that is a synovial structure, such as the coffin joint or the deep digital flexor tendon sheath. No hoof, no horse, as we discovered in lesson seven during week one. A nail puncture to the foot is always a reason to consult with your veterinarian. Eye injuries are quite common because of the position of the eyeball protruding from the side of the head and because of the various blind spots in the horses line of vision and their reactive nature. One of the other reasons we commonly see eye injuries is due to the inquisitive nature of horses and how much they love to graze and look for food. They will slip their necks through fence railings or poke around over their stall doors, putting their heads in places they don't really belong to snatch that last bit of food. Any time a horse displays clamping of the eye, excessive tearing, ocular swelling, or a bluish haze to the cornea, a veterinarian should be contacted. The veterinarian will often apply a non irritating dye to the eye to assess whether or not the cornea has been scratched, and they will use a lens and light system called an ophthalmoscope to evaluate the different chambers of the eye and assess the depth of the abrasion and whether or not there's inflammation in the eye. The veterinarian will inquire how the injury happened and prescribe topical treatments and pain control. This is often an opportunity for the vet to identify existing problems with your horse's eyesight, diet, or behavior, and perhaps point out barn hazards. The cornea is the thin, durable, clear covering of the eyeball. When it gets even a minor scratch, it is very painful. A horse with a corneal abrasion will often show excessive tearing, squinting, they'll clamp the eyes shut, sometimes they'll tilt their head and rub their face. You may not see anything obviously wrong with the cornea, and you may not see any swelling or cuts near the eye. The horse may refuse to eat from the pain because it can be so significant. Corneal abrasions can turn into severe ulcers that can possibly rupture the eye if not addressed in a timely manner. Ulcers can result in permanent scarring of the cornea which can create blind spots in the line of the vision of the horse or they can cause complete blindness if the interior component of the eye becomes infected or scarred. Some cases may progress to the stage that the entire eyeball must be surgically removed, and that is why we always consider a tearing, swollen eye a veterinary emergency. Do you remember how many feet long the equine digestive track is, and the varied functions of each section? As you can imagine, this means there's ample opportunity for things to go wrong along those hundred feet. Horsemen commonly use the term colic for the variety of signs they will see when a horse is experiencing abdominal pain. The reasons for colic can include primary gastrointestinal problems such as mild indigestion, gas, ulcers, parasite infestation, some sort of blockage of the intestine, sand accumulation, overeating, ingestion of a toxic material, infection, an allergic reaction, diarrhea, constipation which is also known as an impaction, dehydration, heat exhaustion, hypothermia, and circulatory collapse, and many others. Other causes of abdominal pain can include the reproductive tract in the mare or stallion, the urinary tract, and other organs that rest within the abdominal cavity. The point is, a horse is very susceptible to colic and there are a multitude of reasons why it might occur. Sometimes, we don't know the cause but we can still provide effective treatment, and approximately 95 percent of colics do respond to medical treatment versus surgical treatment. The symptoms of colic will also vary in type and intensity. Here's where it's really helpful to have a good understanding of your horse and their tolerance to pain. Remember the discussion on whether or not your horse is stoic or expressive? Knowing your horse will help you identify when your horse is in trouble, so you can intercede swiftly and effectively. The multitude of symptoms of colic may occur altogether or they may appear individually and be quite subtle. They can appear suddenly and be very intense or they can come on slowly and build to more intensity over time as they smolder or as the horse becomes dehydrated. Symptoms may vary from one colic episode to the next, and they may happen without any apparent reason. There is a wide variety of symptoms that the horses can show when they're experiencing abdominal pain or colic. Here are few that you can look for. Horses that are experiencing colic will often have a poor appetite, diminished manure production, they will toss their head and paw at the ground with the front limbs, they can kick at the belly with their hind limbs, or turn repeatedly to look at their abdomen. Some will bite at their flank or lay flat out and get up and down repeatedly. In severe cases of colic where the pain is unrelenting, horses will sweat and that sweating is a more serious sign of something going on. They can flare their nostrils and raise their upper lip repeatedly in what is called the flaming response. Repeated yawning can also be a sign of pain in the horse. Often, their vital signs will start to change as they experience this abdominal pain. You may notice an increased respiratory rate or heart rate, and in some cases, you may see a fever associated with colic. Capillary refill time will often slow and the gum color can change, from pale to a severe red or lavender colored gum, and capillary refill time and gum color can be a good indication of what's going on with the horse. If you notice any of these signs, it is generally advisable to call the veterinarian at the onset. You and your veterinarian can determine whether or not immediate medical intervention is needed or whether the horse may benefit from a brisk walk and you pulling the food away and observing it. Some horses will respond well to intermittent walking and grooming which will encourage them to relax and take their mind off of their abdominal pain. Remember not to take them out of sight of their herd, as now is not the time to test their attachment to their buddies and stress them out. Consult with your veterinarian and determine what the best course of action is for your horse when they start to display signs of colic. It is very helpful for you to obtain the vitals of your horse, to look at gum color, and assess hydration as well as look for evidence of manure output before you call your veterinarian so that you can answer those questions on the phone. In many cases, your veterinarian will recommend a colic examination to better assess what's going on with the horse. The veterinarian will take a thorough history, they'll observe the horse in its current state and pain, and then check vital signs and perform a thorough examination which may include a rectal exam. This means the vet will put on a thin, long, plastic glove over his or her arm and coat it with a lubricant. The vet will gently insert their arm into the horse's rectum to palpate or feel some of the internal structures of the digestive track for specific clues for the reason the colic episode is occurring. Most horses are tolerant of this procedure especially with mild sedation or restraint. After a complete physical examination and rectal examination, the veterinarian may choose a variety of treatments based on the symptoms, degree of pain, history, and findings of the exam. If the horse's symptoms do not resolve with routine medical therapy which also can include passing a nasogastric tube and administering water, electrolytes, plus or minus mineral oil, the vet may advise transport to a veterinary hospital for further evaluation, supportive care, or monitoring for surgery if the horse does not respond initially to medical therapy. A rectal exam should only be performed by a veterinarian or someone who has been trained to do this procedure, as there are inherent risks to the person performing the rectal exam and to the horse should an adverse reaction occur. Treatment for colic will often involve supportive care such as oral or intravenous fluids and pain management. The veterinarian will likely insert a specially designed long, soft tube which looks similar to a hose into the horse's stomach by guiding it through the nostrils of the horse and through the long esophagus. This is called a nasogastric tube. This is used to relieve gas or fluid buildup in the stomach, and to administer oral fluids, electrolytes, and other laxatives that can promote the relief of impaction. Sometimes, the veterinarian will get a clue of what has caused the colic by evaluating the material that flows out of the tube. If the veterinarian detects a large quantity of fluid coming back out of the tube, which is known as reflux, that is a sign that a more serious obstruction is going on and that the fluid material cannot exit the stomach through its normal avenue and is backing up out the tube. In many cases, the tube is left in place for the duration of the colic exam to continue monitoring progress and administering treatment if necessary. Attending to a colicky horse can be very scary and exhausting. Colic can also be one of the more dangerous conditions you will attend to because a horse in severe pain will forget their training and manners, and then your safety can be put at risk. Remember the safe zones of the horse and that keeping your horse walking at a brisk pace can really take their mind off of the pain while you wait for the veterinarian to arrive. If possible, lineup caretakers for yourself to provide you with hydration and support while you care for your horse. Before we leave the topic of common diseases and injuries, I'd like to add a final note about the value of research and the benefits of research for both equine and human health. The study of equine veterinary medicine can inform human medicine and translate into advancements in medical options for both species. The horse is a great large animal model for joint health and much of what is practiced in humans today has been gleaned from many years of equine joint therapy. Nationally, approximately three million dollars is available through foundations and granting organizations to fund projects that explore new, preventative, diagnostic, and therapeutic options for horses. This is a very small budget when you consider funding for human diseases. As you think about what you can do for horses on a larger scale, realize that investing in knowledge and supporting research that advances veterinary medicine is a great way to give back to the horse. There are a number of welfare safeguards in place for conducting equine research. All research conducted in an academic setting in the United States must be approved by an Institutional Animal Care and Use Committee or IACUC committee. All protocols are reviewed by a board of scientists and community members to assure humane treatment of animals. The focus is on the three Rs: reduction, refinement, and replacement. All protocols are reviewed with the goal to minimize any pain or anxiety, to replace live animal study with models of possible, and to ensure the humane care of animals housed in a laboratory setting. As with human medicine, equine research advances options for care and positive outcomes. Progress in the area of colic management, fracture repair, imaging, neonatal care, infectious disease diagnosis and treatment, and musculoskeletal health have been tremendous in the past 40 years. The tools that veterinarians have in their hands today are far more advanced and accurate than what they had 40 years ago. Researchers continue to push the envelope to discover new ways to treat troubling diseases like laminitis. Here at UC Davis, for instance, there's groundbreaking research being conducted on injury prevention in race and sport horses. There is much work to be done and support of local schools of veterinary medicine with strong research components is a great way to make a difference for horses in general. That concludes our overview of the common illnesses and injuries we see as veterinarians. Always remember that whenever in doubt about an injury or an illness, contact your veterinarian. Next week, we'll delve into one of the most interesting areas of study: Equine Behavior. We'll look at normal and abnormal behaviors and how to deal with some of the more troublesome behaviors. Hope to see you again next week.
