Unlike a fussy child sifting through a meal to prevent accidental ingestion of vegetables, a cow when presented with a suitable food source will forgo this analysis of the contents of the food in favour of rapid ingestion.
This can result in the occasional and accidental uptake of foreign material. Accidental ingestion of sharp pieces of metal can result in perforation of the stomach wall and can lead to hardware disease.
The reticulum is the first stomach of a cow. This stomach sits right up against the diaphragm. It is in here that any heavy metallic objects ingested will accumulate. Anything sharp like a nail or a fencing wire has the possibility to be squeezed through the stomach wall. The escape of stomach contents and bacteria through the stomach wall will result in a severe infection in the abdomen. There is a possibility that the sharp piece of metal can penetrate forward from the reticulum, through the diaphragm and into the pericardial sac surrounding the heart. An infection in the pericardial sac can prevent effective function of the heart and lead to heart failure. This pericarditis and its associated clinical signs make up the condition known as Hardware Disease.
Cows suffering from Hardware Disease can have signs ranging in severity depending on the location, extent and duration of the infection. Consistently animals will show signs of abdominal pain, standing with a wide based stance, reluctance to move, head extended and occasionally grunting when breathing. Signs including anorexia, weight loss and depression will be noticed with more chronic infections. Once the disease progresses to full blown heart failure there will be signs of peripheral oedema, distension of the jugular veins and an increased respiratory rate.
Likely sources of the metallic foreign bodies include discarded pieces of wire from fencing as well as contamination of brought-in supplementary feed.
This heifer presented with a three week history of being off her milk. She had received a course of Bivatop (oxytetracycline) treatment which had failed to provide any noticeable improvement. A few days before we arrived on farm she had started to become very slow and depressed and had developed a large soft swelling under her jaw.
Her temperature was markedly raised indicating she was suffering from a very severe infection. Her heart sounds were very difficult to hear and her jugular veins were heavily distended. All these signs help to point towards Hardware Disease.
The heifer was secured in a head bail and prepared for surgery. A rumenotomy was performed involving surgical entry into her abdomen from the right side then stabilisation and entry into the rumen. The hole in the rumen had to be large enough to perform a thorough exploration.
After a lot of searching and scrounging around at shoulder’s length in the vast space of the heifer’s stomach a small piece of wire measuring approximately 3.5cm was located and heroically wrenched from the wall of the reticulum. The source of this wire has yet to be determined.
She was then stitched back up, given a decent amount of pain relief and started on a course of penicillin antibiotic. Though she has a long road ahead of her, now that the source of the infection has been removed she has a much better chance for recovery.