ArizonaRealCountry.com 5 September 2018 Q: My horse seems to drink and pee a lot, is this abnormal? A: Excessive drinking and urination are technically called polydipsia/polyuria, or more conveniently, PU/PD. Some horses are naturally big drinkers with the resultant soggy stall that requires a monumental mucking out every day, while others are very fastidious. If you think that your horse is suddenly drinking too much, try putting a water bucket in her stall to monitor exactly how much she is drinking. Depending on environmental conditions the average horse will consume about 6 to 8 gallons of water and produce about 5 to 6 gallons of urine each day. Horses in heavy exercise will drink more to compensate for sweat losses. So the first question should be what has changed lately in this horse’s routine? A change in exercise levels, daily activities, turnout, weather, pregnancy/lactation, and diet can all contribute to altered water intake. If you determine that she is actually drinking more than she needs, blood and urine testing should be performed to determine where the problem lies. For some horses, excessive drinking is a behavioral problem like cribbing. These ones will have very dilute urine but are able to concentrate it easily if their water supply is reduced. Beyond that, there is a myriad of other causes of PU/PD, including endocrine problems such as Cushing's disease, kidney, and bladder infections, metabolic disturbances, plant and drug toxins, and cancer. You may wish to discuss your concerns with your veterinarian in order to develop a plan for determining if this mare indeed has a medical condition that is causing her apparent thirst. Q: My horse has a bladder stone. Is there a way to prevent this from reoccurring? A: I am sorry to hear that your horse has developed a bladder stone. Little is known about equine bladder urolithiasis because it is quite rare when compared to the occurrence in dogs and cats. No breed, age, or gender predispositions have been identified, although they tend to cause more problems in male horses due to the long narrow urethra. In order for a stone to form, a nidus of calcium sloughed epithelial cells, and other debris must combine with concentrated urine and low urination frequency. Under these conditions, the tiny nidus can start to accumulate layers of mineral until it becomes too large to pass out easily in the urine stream. Chronic dehydration, high calcium diets, alkaline urine, bladder wall trauma, and urinary tract infection are all thought to play a role in this process. Unfortunately, a recent study found that 12 of 29 horses treated for bladder stones had a reoccurrence of the condition. There are no guaranteed methods for prevention of this condition, but promoting diuresis (drinking lots of water and passing large volumes of dilute urine) can help by preventing the pooling of concentrated urine in the bladder. Increasing the salt level in the diet and offering flavored water are simple ways to encourage drinking. Horses excrete a lot of calcium in their urine, and the majority of bladder stones are composed of calcium carbonate crystals, so reducing the calcium load in the diet makes sense. Be sure the diet stays towards the lower end of the recommended calcium/phosphorus ratio, around 2:1, and avoid high calcium forages such as alfalfa. Urine must have a relatively high pH in order for a nidus to form, so supplements can be given to acidify the urine (lower the pH). The problem is that huge amounts of these substances must be given to have any effect on pH and it is usually way beyond what any horse would willingly consume. Some clinicians have reported using dietary ammonium sulfate and ascorbic acid (vitamin C) successfully, although there are no published clinical trials confirming the effectiveness of these supplements. In general, it seems that a horse can safely consume about 4000mg of vitamin C twice daily. Infection and inflammation of the bladder also play an important role so monitoring carefully for any problems and treating them promptly can prevent the formation of another nidus, particularly in the immediate post-operative period when the bladder will naturally be quite irritated. My information sources are primarily medical journals and I am sorry to say I have yet to see a helpful source of information to recommend to you beyond these. Q: Are bladder stones common in horses? A: Bladder stones in horses are not common but they do occur. We normally diagnose a few cases each year. Horses naturally secrete a lot of mucus and mineral crystals in their urine, which is why it often looks cloudy. The first sign of trouble is often a little blood at the end of the urine stream when the bottom of the bladder is voided. This is from local irritation of the bladder wall by the rough edges of the stones. Occasionally we will have an emergency situation where a horse is trying to urinate, but can only dribble small amounts because the bladder outlet (called the urethra) is blocked. They are very uncomfortable and this is an emergency because the bladder can rupture and kidney damage can occur from the extreme pressure. Anybody who has been to the vet with a “blocked” cat knows just how miserable they feel! Sometimes we can relieve the obstruction by passing a catheter through the urethra into the bladder; otherwise, the horse will need surgery to bypass the blockage. Fortunately, the surgical procedure can often be performed in a standing horse with epidural anesthesia. A small incision into the urethra just below the anus can provide adequate bladder access in most cases. The prognosis then depends on the amount of bladder and kidney damage that has occurred. The occurrence of stones in any particular horse is difficult to predict and prevent. In conclusion, there is little to be done to prevent stones, so take comfort in knowing that they are relatively rare and stay alert for the subtle signs before an emergency develops. Arizona REAL COUNTRY the magazine Mike Barna Publisher mbarna@963realcountry.com (602) 622-3695 Erika Smith Royal Editor erika963realcountry@gmail.com Misty Voitovski Creative Director Contributing Writers Lee Anderson, Bethany Braley, Desiree’Byrne, Kimmie Dillon, Charlie LeSueur, Jim Olson, Robert Piekow, Liz Potof, Alan Rockman, Bob Roloff, Buddy Uldrikson, JolynYoung Arizona Real Country is owned and published by Barna Broadcasting LLC. No person, organization or party can copy or reproduce the content on our website and/or magazine or any part of this publication without a written consent from the editor’s panel and the author of the content, as applicable. The publisher, authors and contributors reserve their rights with regards to copyright of their work. Follow Arizona Real Country for news, events, giveaways and more! 801 W. Wickenburg Way Wickenburg, AZ 85390 (602) 622-3695 ArizonaRealCountry.com Ask the Vet TO PEE OR NOT TO PEE Unfortunately, a recent study found that 12 of 29 horses treated for bladder stones had a reoccurrence of the condition. Increasing the salt level in the diet and offering flavored water are simple ways to encourage drinking.