January 12, 2005 | By: Ellen Brightwell

Producing high-quality forages is one of the best ways to improve animal performance, whether the goal is a higher rate of gain, more pounds of milk or wool production or an enhanced conception rate.

"The ultimate test of forage quality is better animal performance," said Garry Lacefield, Extension forage specialist with the University of Kentucky College of Agriculture. "Forages provide most of the nutrients for beef and dairy cattle, sheep and goats, horses and ruminant wildlife. If the quality is not adequate, you cannot feed animals enough forage to achieve production goals."

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."

Although many factors affect forage quality, plant species and harvest maturity probably are the most important considerations and the ones over which producers have the most control, according to Lacefield.

Because there is much deviation in quality among different forages, plant species is an important factor in improved animal performance. Legumes generally are higher quality than grasses. Cool-season grasses usually are more digestible than warm-season grasses. Since plant breeders continue to improve quality within forage species, variation also exists among varieties within species.

Protein content, digestibility and acceptability to livestock drop as legumes and grasses advance from the leafy, or vegetative stage, to the seed, or reproductive stage. For instance, grasses may contain more than 30 percent protein when immature, but drop to less than eight percent protein at maturity.

Livestock producers also should consider animals' nutritional requirements and match forage quality to these needs, according to Lacefield. 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 the factors producers need to consider.

"When considering palatability, look at whether animals will eat enough of the forage to meet their daily nutritional needs," he said. "In general, high-quality forages are more palatable. Research shows that animals tend to eat more of the better-quality forages."

Lacefield said digestibility also improves with forage quality.

"Animals may digest 80 to 90 percent of immature, leafy grasses but just 50 percent or less of mature materials with lots of stems," he said. "High-quality forages contain significant protein, energy, vitamins and minerals; but they are low in undesirable content such as fiber and lignin."

The county Extension office has more information on ways livestock producers can improve animal performance.


Writer: Ellen Brightwell 859-257-4736, ext. 257
Source: Garry Lacefield 270-365-7541, ext. 102