What is it? Urinary Calculi is a common metabolic disease in male sheep and goats. The disease is caused when calculi (stones), usually comprised of phosphate salts, become lodged in the urinary tract and prevent urination. Phosphorus is usually recycled through saliva and excreted via faeces in ruminants. However high grain, low roughage diets decrease the formation of saliva which increases the amount of phosphorus excreted in the urine. What Causes it? The primary cause of urinary calculi is feeding concentrate diets which contain significant amounts of phosphorus and magnesium or have an imbalance of calcium and phosphorus. Any feed which does not contain ammonium chloride which helps prevent Urinary calculi is not suitable to be fed to lambs. Which Animals are at Risk? Urinary Calculi can affect intact male lambs and kids, however castrated lambs and wethers are most at risk. Lambs castrated within the first month are most vulnerable. Producers are therefore recommended to carefully consider whether it is necessary to castrate ram lambs. Intact males grow faster and produce leaner carcasses. What are the Symptoms? The signs do vary, however they usually start with restlessness and anxiety. Affected animals may experience abdominal pain and urine dribbling which may be bloody. The lamb may have a humped up appearance and will isolate itself from others. If left untreated, affected animals will die when the bladder bursts and urine is past into the blood stream.