“To get an animal finished on grass, forage must have energy levels similar to a feedlot diet. At the finishing stage, animals have to be able to eat all they want of a high-quality pasture."
"A fast-growing short, green pasture will be very high in protein but very low in energy. You need to use something like ryegrass mixed with clover in a pasture 6 to 8 inches tall. At this height the animal can reach with the tongue and take a full mouthful with every bite. It has to be easy; they can’t be working hard to get full,” says Panner.
“They have to be gaining at least 2 pounds a day during that last 120 days. Look at your climate and determine which 120 days of the year can provide pasture of this quality. Irrigation can extend this period of time."
"Certain forage species have high energy levels, such as sorghum/sudangrasses or Italian ryegrass, brassicas, etc. If you want them to gain 2.5 pounds a day for 120 days, do the math and arrive at the start of that period with an animal large enough to finish in that length of time,” she explains. 
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