I’ve seen a great deal of misinformation on bloat prevention over the years. You would think, as common a problem as bloat is in cattle and sheep, we would all be on the same page with the information.

Years ago, we were told that research had been done to show that frost did not increase the incidence of bloat in livestock. Farmers would tell me that was just plain wrong. Universities all pretty much agree now that frost, and even dew, on legumes increase the incidence of bloat.

Bloat is caused by an accumulation of gas in the first two stomachs of a ruminant animal. Production of carbon dioxide occurs as a natural part of digestion and is usually discharged by belching. If the animal can’t get rid of the gas, it builds up putting pressure on the diaphragm. This can be caused by a froth that layers on top of the rumen content preventing the gas bubbles from rising to the top and bursting. Since the animal can’t belch, the gas is trapped in the bubbles and the condition gets worse.

Pasture bloat occurs when the forage is high in protein and low in fiber. It is most common in pastures that have substantial amounts of alfalfa or clovers in the sward. Immature legumes, which are low in fiber, are most likely to cause the problem. In areas where trefoil can be used as a pasture legume, it is a good choice since it does not cause bloat, by most accounts. Bloat seldom occurs in pastures that are predominantly grass.

Most experts agree that bloat occurs more often when animals go into the pasture hungry and when the animals are first turned into the pasture. Greedy feeders are most likely to get into problems. A rapid intake of lush green legume is often the cause. Frost, dew or even rain can increase the incidence.

To prevent bloat, in the spring, graze pastures, which are 50 percent or more grass. When you first turn animals into a new pasture, try to be sure that they are not hungry. You may even need to feed long stem hay. This reduces the excessive intake. Do not turn into a new pasture when dew or frost is on the legumes. Try to stick to a routine of moving animals from paddock to paddock.

One of the best practices for prevention of bloat in cattle or sheep is feeding poloxalene. It is a surfactant that helps prevent the formation of foam in the rumen.

This farm news was published in the May 24, 2006 issue of Farm World.