Urolithiasis in livestock – what is it and what causes it?

Bladder stones form as a result of minerals in the urine forming crystals that grow on to become stones.

Bladder stones may either pass in the urine or remain in the bladder, in which case they are not an issue.

It is when they become stuck in the urethra and cause a blockage that they become a problem as the animal then cannot urinate. This is condition is known as urolithiasis.

Urolithiasis is mainly seen in wethers and feeder steers.

The first sign of urolithiasis is restlessness as the animal attempts to urinate. A swelling is then often seen around the pizzle.

Finally, the animal may die due to the toxic effects of not being able to urinate.

Urolithiasis is particularly seen in animals fed primarily grain rations.

Grain is relatively high in phosphate but low in calcium. This imbalance predisposes the production of phosphate rich stones.

When feeding grain, the most effective way of preventing urolithiasis is to add calcium in the form of ground limestone.

In addition, it is important to ensure that ample water is available to prevent dehydration. The provision of salt will help stimulate water intake.

For further information, contact your local veterinarian or Agriculture Victoria veterinary or animal health officer, or in NSW your Local Land Services.

– Dr Jeff Cave is an Agriculture Victoria senior veterinary officer.