Some of the growing demand for grass-fed beef could be met by grazing calves on a legume called birdsfoot trefoil.
A study at Utah State University showed that birdsfoot trefoil pastures do not cause bloat when grazed since the tannins bind with the protein and don’t cause the stable foam in the rumen that causes bloat.
Jennifer MacAdam, with the Department of Plants, Soils and Climate at Utah State University reported that ongoing studies at Utah State University are demonstrating that spring-born cattle can be finished on legume pastures on a time frame similar to feedlot-finished cattle.
The secret to higher gain, and higher consumer acceptability relative to grass-finished beef, is the high quality of the forage, which has low fiber and high energy and is similar in nutritive value to a feedlot finishing ration, MacAdam said.
All cattle are grass fed until they reach the finishing phase of their growth, the study said. At that point, calves usually are sent to a feedlot for finishing where they consume a high-concentrate died to ad marbling (intramuscular fat) that makes grain-fed beef tender and juicy.
Grass-fed calves grow more slowly and develop less marbling, producing different flavor notes with a less-tender beef product, a market analyst said. This is desirable to some consumers. Other consumers like the idea of consuming beef from cattle that grazed their entire lives.
THE SCIENCE
Most US pastures are seeded to grasses or grass/legume mixtures, MadAdam said. Well-managed pastures have all the protein needed for finishing, but are low in energy, or readily digestible carbohydrates.
Grasses are, however, high in fiber, which is reported as Neutral Detergent Fiber on forage quality analyses, she said. Most NDF is cellulose, which is digested by microbes in the rumen and releases plenty of energy to keep a growing steer healthy.
However, NDF digestion takes far longer than the conversion of (corn, wheat or sorghum) starch into energy, and cattle require a high level of energy to marble well during a 90- to 120-day finishing period.
The concentrated diets of feedlots are low in fiber and high in nonfibrous carbohydrates, so intake and gains are higher in the feedlot than on grass-based diets, MacAdam said.
BIRDSFOOT TREFOIL PERFORMS WELL
The university study of beef gain on irrigated birdsfoot trefoil pastures near Logan, Utah, showed that steers could gain more rapidly on this forage than on high-quality irrigated grasses. The spring-born Angus steers used in the study were weaned at about seven months of age and were fed a ration of alfalfa and corn silage for another seven months up until their respective finishing diets.
Birdsfoot trefoil-finished beef had tenderness and juiciness comparable with grain-finished beef, but the omega-6 to omega-3 fatty acids balance was similar to grass-fed and lower than grain-fed beef.
CATTLE, BEEF RECAP
Eleven hundred head of Nebraska cattle sold last Wednesday on the Livestock Exchange Video Auction at $110 per cwt, steady with the last sales three weeks earlier.
Cash trade was reported last week at $172 to $173 per cwt on a dressed basis, down $6 to $7 from the previous week. Live-basis cash action was seen at $108 to mostly $109 to $110, down $1 to $3.
The USDA choice cutout Tuesday was down $0.86 per cwt at $216.83, while select was off $0.32 at $201.57. The choice/select spread narrowed to $15.26 from $15.80 with 101 loads of fabricated product sold into the spot market.
The CME Feeder Cattle index for the seven days ended Monday, was $1421.75 per cwt, down $0.53. This compares with Tuesday’s Aug settlement of $146.10, up $0.32.