It takes quite a long journey to reach the dead cow.

It was a cold November morning, and I was very happy that Glen had a heater side by side. Glenn only noticed the cow late the previous morning, and the first thing in the morning was to call me out. I'm happy to help; when you can't see the cow, it's frustrating to be asked why a cow will die, let alone a good autopsy.

Glenn’s other cows chewed on corn stalks and knew nothing about losing a compatriot, watching us work along the edge of the field. In front of us lies a huge cow, which looks more spherical than rectangular. She lay in the deep ditch at the edge of the field, and she turned sideways, with her legs aiming at the gentle slope where the cornfield merged with the grassy hills.

"Glen, I think I know what happened, but I will open her heart and make sure I haven't missed anything," I told the rancher while pulling out the autopsy knife from my bag.

My inspection showed that a healthy cow about four months pregnant had no obvious problems elsewhere. Swelling is the direct cause of death. When gas accumulates mercilessly in the front stomach of a ruminant that has no outlet, it squeezes the lungs and blood vessels, suffocating the animal.

"Glen, I'm afraid she is unlucky."

The place where the cow decided to lie down was her unfortunate fall. In the furrow with her back downhill was a position where she could not get up easily. Struggling may make her fall into a worse situation, and her fate is doomed. The cow hasn't figured out how to turn over on its back like a horse.

What we are encountering here is a disruption in rumen physiology. To get rid of the 10 gallons of carbon dioxide and methane that cows produce per hour requires cows to hiccup. Usually this is not a big deal: the gas floats to the top of the rumen "vat", and the opening of the esophagus is ready to be used as an outlet. This particular cow positioned herself (and her rumen) so that the opening of the esophagus was blocked by liquid. The gas cannot find an outlet.

If you find an obviously bloated cow in the deep water (severe breathing difficulty), the risk of death is high enough, and you should consider taking extreme measures to relieve the pressure on the rumen. A section of hose extends into the mouth and throat, and it is likely to reach the air cap and let it flow out of the hose. Place a speculum (a small piece of metal or heavy PVC pipe) in the mouth to insert the hose into the mouth to prevent the cow from chewing on the hose.

But hoses and pipes are rarely available when you need them. This brings us to the "surgical" method for emergency relief of abdominal distension: pierce the body wall and rumen with a sharp knife to allow gas to escape from the side of the cow. This needs to be done on the left side of the cow (standing behind her and looking at it), about one hand wide behind the edge of the rib cage. It was scary to implement, but it might save her life.

Fortunately, the vast majority of cows will not put themselves in these situations. But I have been conducting on-site investigations and answering calls from producers who have experienced this situation many times, asking the question whether there is a potential factor that causes cows to succumb to "location inflation".

The proportion of pregnant cows in cases of postural bloating is too high: their increased abdominal filling makes it more difficult to move up and down and exacerbates the effects of bloating. Cattle grazing on hilly pastures or dry land with many ruts and depressions eat grass more easily than flatlanders.

When multiple positional bloating occurs, it is necessary to carefully check the nutrition and physical condition of the cow. Most dairy cows have enough energy and strength to get rid of the most difficult situations, but pregnant dairy cows in poor physical condition consume their energy in extreme winter weather, usually not.

Hope all your cows have no such problem when they hiccup in winter. But if it is not, then understanding what to look for, what to do in an emergency, and how it might be possible to prevent these problems may be the difference between life and death.

Russ Daly, DVM, is an extension veterinarian at South Dakota State University.