Abstract
Two total mixed rations (TMR) of rice whole crop silage (RWCS-TMR) and Sudangrass hay (SGH-TMR) were investigated on dry and lactating cows to determine the feed property and animal performance, respectively. The RWCS was lower in contents of crude fiber and neutral detergent fiber than the SGH, in accordance with its higher contents of nitrogen-free extracts and non-fiberous carbohydrates (NFC). On a constant feeding trials of RWCS-TMR and SGH-TMR, the RWCS-TMR showed a significantly (P<0.05) lower TDN content as compared to that of SGH-TMR, although their TDN and CP contents were designed to be the same by being composed of 21% SGH or 21% WRCS on DM basis. The RWCS-TMR also had lower digestibilities of starch and NFC (starch: P<0.01, NFC: P<0.05) than the SGH-TMR, as shown by over 60% excretion of indigested rice grains in feces. As a lactation trial was conducted with dry matter composition of 21% SGH and 26% WRCS in the corresponding of the two TMRs, respectively, the DM intake by lactating cow was not different between the two TMRs, while the fat-corrected milk and solids not-fat contents were lower with the feeding of RWCS-TMR.
