Strategies to deal with bloat in cattle grazing alfalfa

Source: Saskatchewan Agriculture and Food

Grazing cattle on alfalfa has proven advantages. The crop grows well without the need for nitrogen fertilizer, keeping operating costs low. It also provides the kind of high-quality feed that reduces production costs per animal. Additionally, it has environmental benefits in terms of soil protection and lessening the generation of methane in a cow’s digestion process.

Alfalfa is often combined with grass when it is incorporated into a pasture stand. However, a concern that can make producers think twice about including it in their forage mix is the risk of bloat.

But Lorne Klein, a Forage Development Specialist with Saskatchewan Agriculture and Food (SAF), says there are some general guidelines that can help cattle farmers deal with that risk.

“One strategy to reduce the threat of bloat is to include non-bloating legumes in the seed mix, such as sainfoin or cicer milkvetch, along with the alfalfa and grass,” he said.

Other seeding techniques that will mitigate bloat risk include using the bloat-reduced alfalfa variety (AC Grazeland), selecting grass species that re-grow quickly after grazing, using an alfalfa species that re-grows slowly after grazing, and seeding the mix together in the same seed row rather than separate rows.

“You can also manage bloat risk by monitoring the state of plant growth and moving the herd accordingly,” Klein noted. “The greatest risk of bloat occurs during the alfalfa’s rapid vegetative growth before flowering occurs.”

Other risk factors to watch for include frost damage in spring and fall, and the presence of morning dew, both of which tend to increase the likelihood of bloat occurring. Klein says it is also important that livestock grazing alfalfa have a good water supply, as well as salt and mineral ration.

There are bloat control products available on the market that will similarly reduce its occurrence. They include Rumensin CRC, a controlled release capsule administered orally before turning the cattle onto pasture, and Bloat Guard, which is very effective when fed daily.

There are other products under development or in use outside of Canada, but they have yet to be approved for use here.

Klein notes that livestock selection may be an additional factor in decreasing bloat on an alfalfa/grass forage mix.

“Cattle’s tendency to bloat is believed by some to be inherited,” he said. “That suggests keeping replacements from known low-bloat cows. There is also some belief that livestock can learn how to graze alfalfa more slowly.”

Klein stresses that every strategy has its limitations, and there is no absolute guarantee that producers grazing on alfalfa will not witness some bloat in their herds. However, these practices have shown results in reducing that risk.

More information on forage and grazing, including suggested approaches to prevent bloat in cattle, can be obtained on the SAF website at www.agr.gov.sk.ca or by calling the Agriculture Knowledge Centre at 1-866-457-2377.

For more information, contact:
Lorne Klein, Forage Development Specialist
Saskatchewan Agriculture and Food
Phone: (306) 848-2382