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Sainfoin in alfalfa | New sainfoin varieties tolerate cutting and control bloat caused by alfalfa

LETHBRIDGE — The pink flowered sainfoin is a good addition to a forage stand because it prevents bloat in cattle that have indulged in too much alfalfa.

Yet few people use it in their grazing programs, say forage specialists.

It may need more promotion be-cause economic studies and performance trials on grazing cattle show it is a good addition to a grazing program.

A field day devoted to sainfoin at Agriculture Canada’s Lethbridge Research Centre talked about its pros and cons.

The forage is not used often be-cause it does not survive well in mixed alfalfa stands and it does not regrow well after grazing or mowing, said forage plant breeder Surya Acharya.

That could be changing.

“We have developed several new sainfoin populations with the ability to survive in mixed alfalfa stands, tolerating frequent cutting and producing high biomass yield,” he told the July 30 field day.

Its main attribute is its ability to control bloat, which is a serious problem with straight alfalfa.

Cattle like the taste of alfalfa and it is nutritious. It is digested rapidly, and the rapid fermentation in the rumen can cause a buildup of more than 200 litres of gas per hour.

The gas mixes with the rumen fluid to create bubbles that turn into foam. The animal is unable to burp up the foam and could suffocate and die.

Researchers at Lethbridge and Swift Current have found that a 15 percent addition of sainfoin in an alfalfa mix should help control bloat. The problem is the sainfoin is not always spread evenly throughout a field so bloat could still happen.

Observations also show cattle can be picky eaters and don’t mix the forages together. They may leave the alfalfa for last and end up bloating, said researcher Alan Iwaasa from Swift Current.

Research has also shown animals have differing rumen microbe populations, which means some suffer from bloat while others appear immune.

Genetic information is probably required to test the rumen microbes to see which animals are more susceptible.

Bjorn Berg, an Alberta rancher and forage consultant, said sainfoin does not perform as well agronomically as alfalfa.

Alfalfa grows well everywhere in North America, while sainfoin does not seem to do well in black soil zones or wet areas.

Sainfoin was originally from Eastern Europe and grows well in well drained, dry areas. It can handle the chemozemic or solonetzic soils commonly found in Alberta.

It does not seem to establish well if seeded into existing stands of grass, but graziers who included it in their pasture mixes know it reseeds itself and persists.

Sainfoin will outcompete weeds once it is established. Chemical weed controls for alfalfa will work for crops such as sainfoin and cicer milk vetch, but they are not listed on the label.

Growing tame forages of any variety presents other challenges. They do not produce much feed in the first year during the establishment period but become prolific in the next couple years.

The peak yields in many tame forage stands are in years two and three. There may be a severe de-crease in the following years.

As a result, the best time to add inputs would be in the early year.

“If you are going to do this with any of the legumes and sainfoin is in-cluded, pile in the inputs in the first year because your yields in year two and three will be the ones that pay,” said Berg.

That surge of growth may be connected to the soil’s nutrient depth. Nutrients infiltrate the soil over the years and go down deeper through the soil profile.

Legume roots go down almost two metres in the first year, and by the third year the root systems are so extensive they could hit bedrock searching for nutrients and water.