Rice bran is a by-product of the rice milling process and has been well used as livestock feed. Rice bran is often adulterated with rice husk. The objective of this study was to evaluate the in vitro ruminal fermentation characteristics of rice bran with various compositions of rice husk and assess the relationship between rice husk addition and rice bran quality. The experiment was arranged in a completely randomized design with rice husk addition as a factor and three replications. Data of proximate value, gas production, ruminal degradability, and volatile fatty acid production were analyzed by analysis of variance. Moreover, significant effects of each treatment in the in vitro fermentation were further analyzed by Duncan's multiple range test (P<0.05). It was shown that the addition of rice husk to rice bran could increase acetic acid level, but it reduced potential gas production, gas production rate, organic matter and dry matter digestibility, and propionic acid level. Interestingly, the linear regression of dry matter digestibility, organic matter digestibility, and potential gas production showed the high adjusted R2 values. Moreover, this study also revealed that 10% of rice husk substitution on rice bran could significantly reduce the dry matter digestibility.

Solid waste generated by parboiled rice industry are rice bran, rice husk and broken rice. Broken rice can be used for cattle feed as energy source. The aim of this study was to evaluate the effects of parboiling process on the in vitro rumen fermentation. The experiment was arranged in a completely randomized block design with 2 rice varieties (LIPI Go 1 and Sintanur) as blocks, 2 different soaking periods (30 and 60 minutes) as treatments and 3 replications. Parboiling treatment was significantly (P<0.05) increased crude protein, organic matter, and crude fiber, but decreased ether extract and solubility. LIPI Go 1 produced higher (P<0.05) gas (11.18%), but lower (P<0.05) gas production rate (52.38%) and methane (10.27%). Soaking rice grain for 30 and 60 minutes decreased rumen dry matter digestibility by 6.13% and 8.90% and increased post rumen dry matter digestibility by 10.41% and 10.43%, respectively. Moreover, 3.55% and 6.84% from total samples of parboiled rice treated by 30 minutes and 60 minutes soaking periods were digested in the ileum. As ruminant feed, parboiled rice decreased methane and digestibility in rumen, and increased the digestibility in post rumen and ileum.

<abstract> <p>The objective of this study was to determine the characteristics of fresh rice straw silage quality prepared with addition of <italic>Lactiplantibacillus plantarum</italic> 1A-2 and crude cellulase alone or in combination. Quality of the silage was observed through the chemical composition, chemical structure and <italic>in vitro</italic> digestibility. Six treatments were used in this study, i.e., 1) rice straw without any treatment as control, 2) rice straw with addition of 0.1% <italic>L. plantarum</italic> 1A-2 (LAB1), 3) rice straw with addition of 1% crude cellulase (E1), 4) rice straw with addition of 0.1% <italic>L. plantarum</italic> 1A-2 and 1% cellulase enzyme. (LAB1 E1), 5) rice straw with addition of 2% crude cellulase (E2), 6) rice straw with addition of 0.2% <italic>L. plantarum</italic> 1A-2 and 2% crude cellulase (LAB2E2). Each treatment was replicated by four times (n = 24). Ensilage was carried out for 60 days. Data obtained were analyzed by using one-way analysis of variance (ANOVA) according to complete randomized design. The result indicated that the treatments increased dry matter (DM) (p = 0.001), crude protein (p &lt; 0.001) and lactic acid (p &lt; 0.001). Meanwhile, reduced pH (p &lt; 0.001) and organic acids (acetic, propionic and butyric (p &lt; 0.001)). Total crystallinity index (TCI) of rice straw silage varied among treatments and decreased in crystallinity (%) except for LAB2E2, which showed the lowest crystalline size. The treatment increased DM digestibility (p = 0.397) with the highest in LAB2E2. There is significant effect (p &lt; 0.001) on increasing the main SCFA products from <italic>in vitro</italic> rumen fermentation. This study suggests that addition of <italic>L. plantarum</italic> 1A-2 inoculant alone or with crude cellulase improved fresh rice straw silage quality.</p> </abstract>