You have all probably heard of a cow being diagnosed with Hardware Disease and may be fairly comfortable with what that disease syndrome is. I often find, however, that there are a lot of misunderstandings about Hardware Disease and so I’m going to attempt to clear up some of those here.
Let’s start by defining Hardware Disease. Hardware Disease is a syndrome that occurs after an animal has ingested a metallic object that then perforates the wall of the reticulum. This perforation results in infection in the area which can be mild or severe. In the ruminant animal, the reticulum is the first chamber of the forestomachs that lies below the bottom of the esophagus. The weight of metallic objects causes them to fall to the bottom of the reticulum, where they remain. Unlike in other animal types, where foreign objects typically move through the gastrointestinal tract until they either cause a blockage or are passed out, the anatomy of the reticulum and the weight of the object nearly guarantee that the piece of hardware will remain there forever.
The reticulum is about the size of a volleyball and its lining looks like a honeycomb. It functions to mix feed and help the ruminant eructate gas by having rhythmic contractions. This honeycomb interior can trap the ends of the wire and the contractions can force the ends through the wall, resulting in a few different possible scenarios. These include local infection around the reticulum from leakage of fluid from the reticulum up to the most severe outcome, which is puncture of the sac around the heart. Local infection around the reticulum interferes with normal gastrointestinal flow and motility, causing mild to severe disease. How does the heart get involved? It has the curse of being in the wrong neighborhood. Anatomically, the reticulum and the heart sit right next to each other, on either side of the diaphragm. If the contraction of the reticulum pushes the wire forward toward the heart, it can pass through the diaphragm and into the sac surrounding the heart, with a catastrophic outcome.
There are some symptoms that may be shown by affected cattle that very strongly suggest a diagnosis of Hardware Disease. These include standing with the head and neck extended, grunting, and standing with the elbows pointed out. All of these point to pain in the area of the junction of the thorax and abdomen. More commonly, however, the symptoms associated with Hardware Disease are more generic, with many animals simply showing weight loss over time.
Hardware Disease can be tough to definitively diagnose. For this reason, when cattle are losing weight and the cause is not readily apparent, Hardware Disease is often blamed. Several tests can be performed to help confirm a diagnosis of Hardware Disease, including xrays to look for the presence of a wire or other metal object in the reticulum, ultrasound, and analysis of certain blood proteins.
It is critically important to confirm a diagnosis of Hardware Disease (or other syndrome) in an individual animal in order to benefit the herd. Many diseases of significance in cattle have some impact on their herdmates, either because the disease is directly contagious between animals or because all of those animals live with the same risk factors. For Hardware Disease, it’s about risk factors. Metallic foreign objects are obtained from the environment, so all animals in the herd are potentially at risk. What is it about cattle that puts them at higher risk than other species for Hardware? Their tongue. You’ve noticed that as a cow eats, she sweeps up grass using the length of her tongue. By contrast, sheep, goats and horses use their lips and teeth to grasp grass. Cattle, therefore, are likely to sweep up objects present in the pasture while other livestock are more likely to sort it out. Attention to debris in pastures is of paramount in prevention of Hardware Disease. If you mix your own feed and particularly if you’re chopping hay, it’s easy for wires or other metal pieces to be chopped up and mixed into the feed where it becomes nearly impossible for a cow to sort and drop it out of what she consumes. Spend the extra time it takes to remove all wires from bales and dispose of them out of the pasture.
Remember that your veterinarian is the best source of information for all aspects of cattle health. Be sure to ask any questions that you have and have any unexplained illnesses or deaths investigated in order to have the information necessary to protect the health of your herd and improve their productivity.
This is an Xray image of the lower portion of a bovine abdomen. In it, you can see a metallic wire that is contained in the reticulum, placing this animal at risk of Hardware Disease.