Understanding faba bean forage
by Kim Waalderbos
Faba bean forage is becoming an attractive consideration, spurred by the growth in acres of that crop, along with mycotoxin and pest pressures affecting the corn and cereal grain, and crops typically used for livestock concentrates and silages.
However, many questions remain about faba bean forage, including animal feeding values, best management practices for harvesting, and if frost damaged faba beans can be salvaged as a livestock forage source.
“Our intent is to provide pulse and cattle producers with this knowledge so they can make choices to get the highest value and nutrient availability,” says Peiqiang Yu, a Department of Animal and Poultry Science professor and Ministry of Agriculture Strategic Feed Research Chair with the University of Saskatchewan.
Yu is leading a three-phase study that evaluates many details at various steps, from the field to the forage, in the rumens of beef and dairy cattle.
In the first phase, the feed values of faba forages and faba beans are being studied. To start, the team has collected 24 samples (eight varieties per three locations in Saskatchewan). “We are studying each in more detail to determine the structural, physicochemical, and nutritional characteristics,” Yu says. From these analyses, the team hopes to identify if particular varieties are better suited for meeting ruminant nutritional needs.
The varieties are CDC Snowbird, CDC Snowdrop, 219-16, Fatima, Vertigo, FB9-4, 346-10, and SSNS-1. To represent different soil and environmental conditions, the three locations selected are Meath Park, Outlook, and Rosthern.
Next, the researchers are evaluating harvest options using plots at the Crop Development Centre (CDC). “We are doing three cuttings at different plant growth stages to evaluate which is best,” Yu says. Along with silage and beans, the team is evaluating if it is possible to make hay with
faba beans. Crop residues after harvest are also being recorded.
Both high-tannin and low-tannin faba bean varieties are being evaluated and the differences are being noted for future phases in this study, Yu says. “We want to determine if tannin levels matter to ruminant animals, and if so, what is an optimum feeding level.”
Yu says the protein and starch from faba beans have been found to degrade quickly when fed to ruminants. “This can lead to nutrient loss and cause digestive problems in ruminants,” he says. The team is looking at how processing methods can improve nutrient utilization and degradation.
Unexpected cold climate conditions can lead to frost damaged and frozen faba beans in Saskatchewan. With a baseline understanding of how normal faba forage and beans test for nutrient value from this study, the research team plans to measure and compare samples from frozen faba beans to see if they can be salvaged for livestock feeding.
In phases two and three of this study, Yu plans to develop guidelines for feeding faba forages and faba beans to dairy and beef cattle. “We will select the best varieties identified in phase one, and then grow them on a larger scale to study how we can feed it to beef and dairy cattle,” Yu says. “We will
compare to barley and corn grain and silage to determine if faba beans can replace them and at what rates.”