Nuts and bolts of hardware disease

For many years Agriculture Victoria has conducted disease surveillance projects at Victoria’s major knackeries.

A knackery is an accumulation point for diseased livestock, making it a valuable place to look for new and emerging diseases and to monitor disease trends.

From a veterinarian’s point of view, it’s also a place where you might see an interesting disease condition.

During one visit, when looking through the internal contents of a cow, I saw that a piece of wire had pierced the cow’s reticulum (second stomach) and gone through its diaphragm into the sack surrounding the cow’s heart filling it with pus, leading it to die.

My initial thought was ‘how unlucky was that’. But what I saw was actually not that uncommon, and a recognised condition in cattle known as hardware disease.

Cattle are not talented at selectively grazing and what they eat they tend to swallow.

This may include offcuts of fencing wire, fencing staples, nails, and any other pieces of rubbish left lying in a paddock.

This is especially the case if something like an old tyre goes through a feed mixer.

From there, any heavy objects will settle in the bottom of the reticulum of the cow.

The inner surface of the reticulum has a honeycomb pattern which points any sharp objects toward its wall, increasing the likelihood of the wall being pierced.

The reticulum is full of bacteria.

Therefore, if its wall is pierced an infection will follow, either in the cow’s abdomen, its thorax, or as I saw, around its heart.

To prevent hardware disease, it’s vital to not leave small, sharp metal objects lying about in paddocks or stockyards and be extra mindful of what goes into a feed mixer.

One of the treatments for hardware disease is to make the cow swallow a specially designed magnet, which will also sit in the reticulum, capturing any pieces of metal. Occasionally, a veterinarian will operate to try and find and remove the offending piece of metal.

For further advice, contact your local veterinarian.