In recent years, broiler producers have found it increasingly difficult and expensive to find consistent litter materials. According to Dr. Jeremiah Davis of Mississippi State University (MSU), speaking March 19 at the Midwest Poultry Federation Convention (MPF) in St. Paul, Minn., there is great potential in the Southeastern United States to grow large volumes of grass materials from which to source alternative bedding materials.
In the past, studies have been conducted on alternatives to pine bedding, such as rice hulls, peanut hulls, corn stover and bagasse. Other alternatives have included chopped cereal straws such as barley and wheat; paper products, such as newspaper; and sand and gypsum. But, Davis said, there are caking problems with barley and wheat straws and gypsum. Supplies of newspapers are dwindling as more newspapers abandon their print products, and sand litter makes it more difficult to heat the poultry house.
"Our gold standard has been pine shavings over the years," Davis said. But other options may be viable alternatives, studies have found.
In exploring other alternative litter materials, the focus has been on Bermuda grass, switchgrass and giant miscanthus. The latter has offered great promise, Davis said, and MSU has collaborated with Repreve Renewables LLC to grow and study Repreve's Freedom giant miscanthus feedstock for use as poultry litter.
For the Repreve project, growers contract with the company to custom plant the crop - which at full production can yield 14 tons per acre - and manage it based on the company's recommendations. The crop is evaluated by the United States Department of Agriculture (USDA) and several universities. Davis said invasiveness is not a risk because the crop is sterile, there is not live plant in the bedding material, and all the chopped material is dead. Davis said the potential for large volume production of Freedom is higher than the other materials tested.
Freedom giant miscanthus is being grown and tested in Alabama, and Davis believes the plant is almost ready for commercial sale and use.
"This stuff is really at the state of full commercial utilization here," Davis said during the Poultry Litter Management Workshop at MPF.
The floor pen trials compared live production and processing characteristics of large broilers using chopped switchgrass, chopped Bermuda grass and pine shavings. The chopped grasses worked the best when they were kept to one inch in length. Litter was spread in floor pens 3.5 inches deep. Day-old chicks were placed on the litter and were processed at 49 days.
The studies measured the birds' body weight, feed conversion, carcass weight and foot pad condition scores. Birds in each trial performed similarly in each measurement, however, ammonia levels were noticeably lower in houses that used Freedom giant miscanthus, Davis said. He also noted there were fewer footpad downgrades with birds raised on chopped grass litter.
Another benefit of the chopped grass litter includes cost savings associated with transport and drying of litter materials because the chopped grasses have a lower moisture content than green pine shavings.