The Stone-Cold Facts Of Uroliths In Livestock Animals

Water belly, urinary blockage, stones—uroliths have many names, but their presence in livestock animals is a serious condition.

Dr. Evelyn Mackay, a clinical assistant professor at the Texas A&M College of Veterinary Medicine & Biomedical Sciences, speaks of the dangers of uroliths and how livestock owners can recognize the causes and effects of these obstructions in their animals.

“A urolith is a stone that forms in the urinary tract of small and large animals,” Mackay said. “There are a few different types of stones that can form, and they’re usually dependent on the diet and the location of the animal. The most common types of stones we see in Texas are calcium carbonate and struvite stones.”

Made of accumulated minerals, these stones typically form in the bladder of the affected animal, but can also originate in the kidney and then move down into the bladder. If the stones remain in the bladder, they are largely unproblematic. However, they can become harmful if they migrate from the bladder into the urethra, where they cause a blockage.

“We see the biggest problems when the stones move into the urethra in male animals, which either completely or partially prevents them from being able to urinate,” Mackay said.

Male animals are more likely to suffer the harmful effects of uroliths because their urethras are smaller in diameter. Mackay says that uroliths are also more common in some livestock animals, such a sheep and goats, but she also treats cows and pigs for these stones.

“There are a variety of treatment options available, from the less invasive to the more invasive. Once the animal cannot urinate, it can be challenging to treat,” Mackay said. “Early treatment is really important because they can rupture their bladder.”

Symptoms of stones include difficulty urinating, a distended abdomen, and distressed behavior. Symptoms can vary widely depending on the circumstances of each case, so owners suspecting that their animal might be suffering from a urolith should seek veterinary care promptly.

“Dietary management is also important,” Mackay said. “Feed a forage-based diet, mostly grass and hay. Water intake is really important and doing whatever you can to ensure that your animals are drinking and not getting dehydrated. It is also best to feed them the minimum amount of grain, as high-grain diets increase the likelihood of stone formation.”

She also stresses the importance of waiting as long as possible before neutering males, as this allows more time for their urethra to widen. While prevention and understanding the risk factors for uroliths is important, Mackay says that the most impactful thing an owner can do is seek treatment quickly.

“If owners think that their animals have any signs of a urolith, they should definitely get a veterinarian to look at it immediately because early treatment is really important,” Mackay said. “The longer you wait, the harder it is to get a good outcome.”

Pet Talk is a service of the College of Veterinary Medicine & Biomedical Sciences, Texas A&M University.