| Production agriculture is faced with the prospect of having to produce enough food to keep pace with the needs of the world's population, while meeting waste treatment and disposal standards for public health and aesthetic quality (Goldman and Ryther, 1976). With increased level of scrutiny on production practices, animal agriculture particularly began paying attention to its by-products of production, particularly its waste products.; Aquatic plants have been recognized as having potential for animal feed and other uses. Aquatic plants have the ability to utilize the effluent generated by municipalities and the often nutrient-rich wastes from agricultural operations. Aquatic plants that have been utilized in research include water hyacinths (Eichhornia crassipes), cattail (Typha latifolia), algae, seaweed, and duckweed (Lemnacaea). Duckweed is a tiny, free-floating, vascular aquatic plant. It is among the smallest and simplest of flowering plants, a worldwide family (Lemnaceae) of floating monocotyledons. Duckweed has the ability to utilize ammonia, nitrates and mineral from natural and wastewater and convert them to feedstuffs with useable proteins and minerals. Duckweed has a crude protein potential as high as 40 percent depending upon the type of media in which it is grown.; Cattle and sheep were fed duckweed as a portion of the crude protein supplement. In sheep, dry matter digestibilities ranged from 67-71% and crude protein digestibility was similar to soybean meal (77.5 vs. 69.3%, respectively). Acceptance as a feed source was excellent in both sheep and cattle. Average daily gain and gain efficiency was similar in cattle on duckweed treatments when compared to cattle on soybean meal treatments. Plasma urea-nitrogen concentrations were lower (P {dollar}>{dollar} 0.03) for cattle on a diet where duckweed was the crude protein supplement than concentrations for cattle where soybean meal was the crude protein supplement (4.66 vs. 7.15 mg/dl, respectively). No differences were noted for yield grade, hot carcass weight, rib eye area and liver abscesses in cattle on duckweed treatments and those on soybean meal treatments. Duckweed has the potential to be utilized as a crude protein source in the diets of ruminant animals. |
