Dairy Feeding of Rice Hay, 2013


Project Leader

Glenn Nader,
farm advisor, UC Cooperative Extension for Butte, Sutter, and Yuba counties

This project continues studies of rice straw used as a feed supplement in dairy rations.  In 2013 research focused exclusively on improving the digestibility of rice straw.

The major goal of this research has been to identify approaches for management of harvested rice straw that improves its digestibility for dairy cattle.

Rice straw does not “wet” easily, a factor that may inhibit enzyme activity in the rumen of cattle. Another factor at play may be the interaction between certain rice straw sugars and cellulose in the rice cell wall.

Research focused on ways to increase rice straw wettability with a commercially available enzyme product containing cutinase. The rice plant’s water-repelling cutin layer could be affecting digestibility. In tests, rice straw became visibly wetter. Samples are being analyzed for changes in digestibility in a biological assessment. Results will be reported in 2014.

Another part of this research tested rice straw samples harvested in different years for rehydration or water absorbance. Results showed that water absorption or rehydration does not appear to be related to the age of rice straw. Thus, field reports of increased intakes of older straw by cattle are not likely to be from faster rumen hydration.