Wheat pasture grazing: The bloat stops here 

Warm temperatures in February and March paired with much needed rainfall are often the signal of spring being right around the corner, but it can also be prime conditions for wheat pasture bloat. Also known as frothy bloat, this condition can happen suddenly and is an emergency often resulting in cattle deaths. 

Paul Beck, Oklahoma State University animal science professor and Extension specialist for beef nutrition, said frothy bloat is essentially a build-up of gas in the rumen due to a blockage of the esophagus.  

“When it starts re-growing rapidly in the spring, high-quality wheat pasture has lots of soluble sugars and carbohydrates and also has a lot of soluble protein,” Beck said. “The soluble proteins form a fairly viscous layer at the top of the rumen, and then the gas coming from the fermentation of the soluble sugars bubbles up through that, and it causes this really stable foam. The build-up of stable foam blocks off that passageway and won’t let gas escape. Usually that happens through eructation in the rumen.”  

Beck said bloat is especially dangerous this time of year because the wheat is coming out of a period of slow growth, and the extreme highs and lows in temperature lead to rapid forage growth in the afternoons with highs in the 60s or 70s. This new growth is high in protein, sugars, and water content, but low in dry matter and fiber. Then the low temperatures overnight can create the perfect storm for a deadly upset stomach. 

“When we have a frost in the morning, it disrupts those cell walls, and all those soluble contents of the plant cells are even more rapidly available,” Beck explained. “The cattle will get up, start their morning grazing event with this very extreme mixture of nutrients, and that’s why bloat can be provocative at this time of year.” 

Bloat risk decreases as spring converges into summer and forage develop higher fiber content, which slows the rate of digestion for soluble nutrients. Beck said he has not received reports of bloated cattle as of mid-February, but expects to hear of cases soon. 

Prevention 

It’s no secret bloat can happen in a hurry and without warning. The time for interval between the symptoms and death can be short, which is why cattle often perish to this emergency condition. 

“I talked to a producer last year that had gone through and fed cattle at one of his farms and was still on the road going to the next farm when he got a call from the neighbor at the previous farm that said he had cattle down bloating,” he explained. “The cattle were fine just 15 minutes before. So, it can happen quickly. They can go from severely bloated to dead extremely rapidly, and they can go from non-bloated to bloated very quickly as well.” 

The first line of prevention is to provide a mineral that contains an ionophore such as monensin to cattle on wheat pasture in the spring.   

“A monensin-containing mineral or supplement decreases the amount of bloat and the severity,” Beck said. “If you’re checking cattle, you might see some that are slightly bloated, but they aren’t dead. This gives you time when you see those breakthrough bloats to start putting out a bloat guard product with poloxalene blocks, mineral, poloxalene-carrying feed to correct those bloats that you do have this time of year.”  

Beck said he does not recommend feeding poloxalene products throughout the year because of the expense and low probability of bloat during other seasons. However, in late winter and early spring, these products pay for themselves. Beck said many cattle producers supply cattle with low-quality hay, such as straw to provide extra roughage while cattle are in one wheat pasture, but the research does not support this strategy. 

 “In past research at Oklahoma State, professor Gerald Horn had tested that and did not see that it decreased bloat adequately,” he explained. “The intake of low-quality straws is not sufficient to change that bloat profile.”  

However, Beck said feeding moderate quality hay, such as prairie or Bermuda grass hay, can be helpful in reducing bloat. These types of hay are moderate in protein and palatability.  

“The theory is that they have enough intake of this hay to provide the scratch factor that keeps the rumen turnover going and increases the eructation and also slows down the digestibility of the entire diet. If we can get 3 or 4 pounds of supplemental hay consumption by these cattle, that can be adequate to decrease the amount of bloat. However, it’s not going to solve the problem every time because not all cattle will consume the hay products.”  

Treatment 

Beck said it is crucial to offer multiple bloat reduction options to cattle and be observant of cattle showing symptoms this time of year. Cattle continue to command record-high prices at the sale barn, and losing any animals to bloat is a heartbreaker. Beck said there are several options for treatment of bloat. The first line of defense is to administer a poloxalene product, either via feed, in a block or in water.  

Beck said in cases where the animal is close to death, the best treatment is to insert a tube down its throat and administer a bloat ease product to and getting a bloat ease product into their rumen to disrupt the foam. A trocar, a sharp device used to puncture the skin and expel gas immediately, is considered the last resort because it can cause secondary medical conditions. 

“When we use a trocar, we have to puncture the skin, and in many cases, we will wind up seeing peritonitis form because of rumen fluid getting into the gut cavity of those calves,” Beck explained. “The best-case scenario is always that we can catch bloat in time, and before they die. Retained ownership pencils out to work really well this year, but if you start losing a bunch to bloat, it gets expensive in a hurry.” 

Lacey Vilhauer can be reached at 620-227-1871 or [email protected].