Rice Straw Utilization
by Feedlot Cattle-03
Project Leader and Principal UC Investigators
Richard A. Zinn,professor, Dept. of Animal Science, UC Davis
Studies continued for a third year on the potential for using processed or
"macerated" rice straw as a feed ration for feedlot cattle. An additional
objective was added last year to assess the influence of processed rice
straw on the milk production and quality of lactating cattle.
Scientists at the University of California's Desert Research and Extension Center previously developed a large-scale macerator to process rice straw to make it more palatable to cattle. In one trial 90 Holstein steers, segregated by weight were placed into 18 pens and fed a corn-based finishing diet with mixes of sundangrass, rice straw or macerated rice straw supplemented with an enzyme.
Research results support earlier findings that maceration greatly
enhances the feeding value of rice straw by creating greater surface area
and enhancing microbial activity. Furthermore, the combination of an
enzyme-supplemented ration and macerated rice straw improved energy intake
and thus daily weight gain, a fact attributed to increased activity in the
In other trials, the influence of pelletized rice straw was examined on crossbred steers. Experimental diets contained sudangrass hay, rice straw and varying amounts of pelletized rice straw. These studies demonstrated the great potential for incorporation of higher levels of rice straw pellets in growing-finishing diets without adversely affecting cattle digestive function.
A lactation trial in progress is evaluating the influence of enzyme supplementation and maceration on dry matter intake, milk yield and milk composition in response to partial substitution of alfalfa hay with rice straw.