Conservation of rice (Oryza sativa L.) forage and its utilization by ruminants

The chemical composition of a long maturing variety B4259 rice forage cut at different days after transplanting (DAT) 15 cm above the ground showed that crude protein content decreased from 25.2% at 30 DAT to 7.7% at 80 DAT. On the other hand, crude fiber and nitrogen-free extract increased as the plant matured. The changes were similar to those reported for tropical pasture grasses. The result of the study on conservation of rice forage as silage pre-treated with molasses (5 and 10%) and corn grit (10 and 20%) showed that rice forage cut at 50 to 80 DAT can be ensiled successfully without pre-treatment. Ensiling at earlier stage of 40 DAT is acceptable either with addition of molasses (5 and 10%) or corn grit (10 and 20%) as reflected by low pH and good levels of crude protein. Results of the feeding trial using growing goat fed rice forage hay (RFH) and rice forage silage (RFS) in combination with stargrass tended to show that those diets could barely provide enough nutrients for maintenance even with concentrate supplementation. Palatability of RFS appeared to be one of the problems associated with the feeding experiment. The RFS used in the goat experiment was of low quality as reflected by the high pH at level 5.8. Supplementation of RFH at 20% of the estimated dry matter intake to grazing-lactating cows did not induce any observable and significant changes in total milk production, peak milk production in terms of actual and fat-corrected milk yield. This maybe due to the high levels of dry matter available in the pasture (17.4 to 34.0% DM) which could satisfy the requirements of grazing lactating cows including the concentrate offered. The intake of RFH supplementation was very low (450 to 160 g/head/day). Likewise, no significant effect of RFH supplementation on milk fat content and occurrence of post-partum estrus was detected.