Our vets have seen several cases of suspect hardware disease recently. Hardware disease is one of the oldest diseases described in cattle, and while it is common, it can be relatively hard to confidently diagnose. Off-feed cows with vague signs can often be examined and found with very few abnormalities on clinical examination - often these cows are diagnosed with suspect hardware. It is almost impossible to truly rule out hardware in these vaguely off-feed cows, so it is usually on our list of differentials. We also see a few cases where the cow is showing all the signs of a “textbook case” of hardware. Here’s a rundown of the typical signs of textbook hardware, as well as some of the myths about this disease.
Signs of “Textbook” Hardware Disease:
Sudden, dramatic drop in milk production
Arched back or hunched posture
Reduced response to withers pinch
Grunting or respiratory effort
Mild to moderate rumen bloat
Scant dry or loose manure
Cows with Hardware always have a fever
This is false! One case study reviewed 200 cases of hardware disease (which was confirmed by post mortem examination) and found that over half of the cases had normal body temperature, despite having widespread peritonitis (infection of the abdomen). This may be due to the chronic nature of the disease and the ability that cows have to “wall off” infection within their abdomen. So fever is not a diagnostic factor when deciding whether a cow has Hardware, although it can help direct treatment decisions.
Vague signs of Hardware Disease:
● Partially reduced appetite
● Decreased milk production
● Changes in manure consistency
● Spending more time laying or standing
● Mild rumen bloat that comes and goes
● Cool extremities
Keep these signs in mind when dealing with off-feed cattle. Often these are described as “ADR cows” (Ain’t Doin’ Right). It is never a bad idea to give a cow a magnet while waiting for a vet to examine her. Treatment for Hardware can range from a magnet, to supportive treatment like calcium, anti-inflammatories, small volume oral fluids, to antibiotics (often multiple). Your vet will help decide what is best on a case-by-case basis.
Putting a second magnet in a cow that already has one will do more harm than good.
This is also false! Many farms routinely put magnets in their cows as heifers, so sometimes when examining an older cow it is possible that she already has a magnet, and farmers are often wary of giving her another one in case it “cancels out” the one she might already have. This simply does not happen. The magnets will just stick together if they find their way to each other. It is possible that the first magnet is already covered in metallic debris anyway, or rendered ineffective for some other reason. Certainly you can always check for a magnet, but if you don’t find one with a compass, giving another one will not cause issues if she does already have one.
Lastly, remember that magnets will only work for metallic or magnetic debris. Other sharp objects can also cause hardware if ingested, and so a magnet is not a perfect solution in every case.