January 5, 1999 | By: Ellen Brightwell

Producing high quality forages is vital to improved animal performance, whether your goal is more pounds of milk, a higher rate of gain, increased wood production, or an improved conception rate.

"The ultimate test of forage quality is better animal performance. Forages provide a major percentage of the nutrients for beef and dairy cattle, sheep and goats, horses and ruminant wildlife. If the quality isn't right, you can't feed animals enough forage to achieve your production goals," said Garry Lacefield, Extension forage specialist with the University of Kentucky College of Agriculture.

Lacefield defined forage quality as "the extent to which a forage, whether pasture, hay or silage, has the ability to produce the desired animal response."

While many factors affect forage quality, the stage of maturity at harvest is the single most important consideration and the one over which producers can make the most progress, he said. Protein content, digestibility and acceptability to livestock drops as legumes and grasses move from the vegetative, or leafy, stage to the reproductive, or seed, stage. For instance, grasses may contain more than 30 percent protein at the immature, leafy stage, but drop to less than eight percent protein when they mature.

"In addition, plant species is another important factor because we have considerable deviation in quality among the various forage species," he said. "Generally, legumes are higher quality than grasses. Cool season grasses usually are more digestible than warm season grasses. Plant breeders continue to improve forage quality within species, so variation also exists within species among varieties."

In addition to forage quality, Lacefield said producers also need to consider animals' feed utilization needs and match the quality to these needs. For example, a high-producing dairy cow needs a more superior quality feed than a dry, pregnant beef cow. Palatability, intake, digestibility and nutrient content are among these considerations.

"When considering palatability, look at whether animals will eat the forage. In general, high-quality forages are more palatable. A forage must be palatable for animals to consume enough to meet their daily needs. Research has shown that animals tend to eat more of the better quality forages," Lacefield said.

Digestibility also improves with forage quality. Animals may digest 80-90 percent of immature, leafy grasses but only 50 percent or less of mature material with lots of stems. High-quality forages have significant amounts of protein, energy, vitamins and minerals, but are low in undesirable contents such as fiber and lignin.


Writer: Ellen Brightwell
(606) 257-1376

Source: Garry Lacefield
(502) 354-7541, Ext. 202