The comparison was made between eighteen mutant and four non-mutant rice straw variety in Indonesia in terms of chemical composition, nutrient value and in vitro digestibility. The second objective was to determine the correlation between in vitro digestibility parameters and fibrous component in twenty-two Indonesian rice straw varieties. Rice straw samples were collected in triplicate from three replicate plots. The effect of variety on rice straw quality, nutrient values and in vitro digestibility was analyzed using one-way analysis of variance (ANOVA). Results demonstrated that the rice straw varieties differed (P<0.

This study investigated the effect of harvesting time on concentration and biological activity of tannin in Andrographis paniculata (A. paniculata) leaves and determined the in vitro rumen fermentation and digestibility of diet supplemented with A. paniculata leaves to evaluate its role as herbal supplement in ruminant's feed. A. paniculata leaves were harvested at two time points i.e., before and after flowering phase and the samples were dried to analyze concentration and biological activity of tannin. Rice straw was used as basal diet to carry out in vitro digestibility trial. Four treatments were used including B consisting basal diet only, BBF and BAF each consisting basal diet supplemented with 1% A. paniculata leaves before and after flowering phases, respectively, and BBAF supplemented with 0.5% A. paniculata leaves before and 0.5% after flowering phase. Each treatment was carried out in five replications. Results revealed that contents (mg/g) for total tannin (20.40±1.06 vs 19.33±1.19; P<0.05) and condensed tannin (8.44±0.17 vs 5.47±0.30; P<0.01) were greater in leaves harvested after flowering compared with before flowering phase, however, no significant difference (P > 0.05) on biological activity of tannins was observed between the two flowering phases. The in vitro gas production was not influenced (P > 0.05) by the supplementation of A. paniculata leaves before and after flowering phase. A. paniculata supplementation also did not influence (P > 0.05) in vitro organic matter digestibility (IVOMD) and total volatile fatty acids (TVFA) values. It was concluded that the supplementation of A. paniculata leaves before and after flowering phase in the diet does not affect the digestibility.

<p class="MDPI17abstract"><strong><span lang="EN-US">Tujuan:</span></strong><span lang="EN-US"> Penelitian ini bertujuan untuk mengevaluasi pengaruh iradiasi gamma terhadap kandungan nutrien, fenol dan aktivitas biologis tanin daun nangka (<em>Artocarpus heterophyllus</em>). Aktivitas biologis yang dimaksud adalah kemampuan tanin dalam mengikat protein yang terkandung dalam substrat pakan.</span></p><p class="MDPI17abstract"><strong><span lang="EN-US">Metode: </span></strong><span lang="EN-US">Perlakuan </span><span lang="EN-US">penelitian</span><span lang="EN-US"> adalah: </span><span lang="EN-US">DN (daun nangka tanpa iradiasi gamma); DN 5 (daun nangka yang diiradiasi gamma pada dosis 5 kGy); DN 7,5 (daun nangka yang diiradiasi gamma pada dosis 7,5 kGy) dan DN 10 (daun nangka yang diiradiasi gamma pada dosis 10 kGy). </span><span lang="IN">Variabel</span><span lang="EN-US"> yang diamati adalah profil nutrien, </span><span lang="IN">fraksi </span><span lang="EN-US">serat, anti nutrien dan aktivitas biologis tanin. Pada pengujian aktivitas biologis tanin, keempat perlakuan ditambahkan polietilen glikol (PEG) sebagai agen inaktivasi tanin. Rancangan Acak Lengkap (RAL) dengan lima ulangan digunakan dalam penelitian ini</span><span lang="EN-US">.</span></p><p class="MDPI17abstract"><strong><span lang="EN-US">Hasil: </span></strong><span lang="EN-US">Hasil</span><span lang="EN-US"> penelitian menunjukkan bahwa iradiasi gamma tidak memberikan pengaruh yang nyata terhadap kandungan bahan organik (BO), protein kasar (PK), <em>acid detergent fiber</em> (ADF), total phenol dan total tanin pada daun nangka. Iradiasi gamma justru menurunkan aktivitas biologis tanin yang direpresentasikan oleh produksi gas kumulatif <em>in vit</em>ro. Walaupun demikian, dosis iradiasi gamma 5; 7,5 dan 10 kGy mampu menurunkan kandungan lemak kasar (LK) daun </span><span lang="EN-US">nangka berturut-turut sebesar 57,82; 83,64 dan 97,09% dari kandungan awal.</span></p><strong><span lang="EN-US">Kesimpulan: </span></strong><span lang="EN-US">Kesimpulan penelitian ini adalah Aktivitas biologis tanin pada daun nangka menurun setelah diiradiasi gamma pada dosis &gt; 5 kGy. Dosis iradiasi gamma 7,5 kGy mampu meningkatkan produksi gas komulatif dan kecernaan bahan organik <em>in vitro</em> daun nangka.</span>

This study aimed to evaluate the in vitro digestibility of rice straw fermented with gamma-irradiated Aspergillus niger. This study was also determined to evaluate the in vitro digestibility of the combination fermented rice straw and rice bran as ruminant rations. A 500 Gy gamma-irradiated A. niger was used for the fermentation process in rice straw by 21 days. Completely randomized design with six treatments and four replications was applied in this study. The treatments were: JNF (rice straw), JF (fermented rice straw), JNF 85 (85% rice straw + 15% rice bran), JF 85 (85% fermented rice straw + 15% rice bran), JNF 70 (70% rice straw + 30% rice bran), JF 70 (70% fermented rice straw + 30% rice bran). The observed variables were the nutrient content, in vitro gas production and in vitro true digestibility (IVTD). The results showed that fermentation treatment by gamma-irradiated A. niger could reduce ADF content of rice straw (P<0.05). however, there was no significant difference in NDF content. JF 70 treatment produced the highest in vitro gas production (P<0.05). JF 70 also produced the highest IVTD (P<0.05). in conclusion, fermentation treatment by gamma-irradiated A. niger could reduce ADF content and increase IVTD. Adding rice bran in ruminant rations was also increase the availability of soluble nutrients for rumen microbes.

In vitro and in vivo testing for ruminant feed efficiency can be done by utilizing the stable isotope Nitrogen-15 (15N) as a tracer. Feed can be traced by labeling the forage using isotope 15N. Feed crops are labeled using an isotope 15N-enriched fertilizer. The critical thing to note is to know the content of isotopes 15N in the part of forage feed plants that have been labeled. This research aims to know the effect of urea fertilizer on the percent of atom excess 15N on corn. Corn are labeled using urea enriched with isotopes 15N in the form of urea fertilizer (10% excess atom 15N) with different doses (0-200% recommended urea dose). As a control used corn plants given urea fertilizer is not labeled 15N. The results showed that corn forage feed was successfully labeled and correlated with the dose of fertilizer. The range of atom excess 15N was 4.28 – 6.99% in corn forage. Biomass production showed no significant difference between the dose of fertilization and control, but neither protein content. Based on data, the corn forage can be used for further testing.