|New Concepts of Rice
Residue for Use as Cattle
Feed - 98
Project Leader and Principal UC Investigators
Glenn Nader, farm advisor, UC Cooperative Extension, Yuba/Sutter/Placer counties
John F. "Jack" Williams, farm advisor, UC Cooperative Extension, Yuba/Sutter/Placer counties
Roger Ingram, livestock and natural resources advisor, UC Cooperative Extension, Placer/Nevada counties
|Several methods of improving the
forage quality of rice straw for cattle were investigated by UC researchers. The Rice
Research Board funded this project to determine whether rice straw could be used as viable
haylage or silage products and, if so, what management factors affect quality.
To determine the nutritional changes in forage quality following harvest, researchers sampled 150-foot windrows at four locations during a 30-day period. Based on preliminary data, it appears that the time of baling rice straw does impact the protein content and digestibility of straw for a feed.
Four small rice plots were treated with different amounts of late season nitrogen to determine whether the protein quality of rice hay could be increased. The applications slightly delayed maturity and significantly increased brown and white rice protein content. The 100-pound rate significantly improved the digestibility and protein content of rice straw for feed. However, the treatment's increase in feed quality did not pay for the cost of the nitrogen. Varietal selection or improved handling could be a more cost-effective method of enhancing forage value. Late season nitrogen applications of nitrogen are not recommended for Japanese varieties such as Akitakomachi and Koshihikari because excessive nitrogen could adversely affects taste.
Another part of this study examined whether, given its relatively low amount of soluble sugars, rice straw could be successfully be fermented into palatable rice silage. Silage is chopped and packed in pits and differs from haylage that is fermented as round bales placed in large plastic bags.
A silage chopper was contracted to follow harvest on a field of sweet rice in late October 1998. The chopped product was taken to a Marysville dairy, packed with a front-end loader, covered with a tarp and left to ferment for 45 days. A sub-sample was treated with a bacteria silage inoculate, sugar and wheat bran. The treated silage had a greener color compared to the brown, untreated silage. Both were fed, along with corn silage as a control, to cattle. The treated sweet rice silage was preferred over corn silage. Furthermore, protein and fiber content were superior in the treated silage. These findings merit further study.
Finally, researchers also successfully created haylage from Akitakomachi and aborio rice types. Samples were field collected, treated with a haylage inoculate and placed in airtight bags for 60 days. Sub-samples were taken for chemical analysis and the products were provided to the same group of beef cattle as the silage for feeding preference evaluation. The cattle preferred the treated aborio haylage, followed by treated Akitakomachi and untreated Akitakomachi.