Judul: Slow Release Urea Nitrate with Starch Polymer Coating Technique for Fermentation and Rumen Digestibility In Vitro, Slow Release Urea Nitrate with Starch Polymer Coating Technique for Fermentation and Rumen Digestibility In Vitro
Abstrak: Penelitian ini bertujuan untuk mengevaluasi pengaruh teknik penyalut polimer amilum yang dilakukan secara in vitro pada urea-nitrat sebagai bahan pakan aditif bagi ruminansia. Penelitian ini menggunakan rancangan acak kelompok (RAK) dengan 5 perlakuan dan 4 kelompok. Perlakuan terdiri dari P0 = ransum kontrol; P1 = P0 + urea tanpa penyalut; P2 = P0 + urea-nitrat tanpa penyalut; P3 = P0 + urea-nitrat dengan penyalut pati sagu; P4 = P0 + urea-nitrat dengan penyalut pati singkong. Parameter yang diamati yaitu kecernaan bahan kering (KCBK), kecernaan bahan organik (KCBO), pH, volatile fatty acid (VFA), konsentrasi amonia (NH3), sintesis protein mikroba, total gas produksi dan produksi gas metan. Hasil penelitian menunjukkan bahwa pemberian ransum perlakuan tidak berpengaruh nyata (P>0,05) terhadap KCBK, KCBO, pH, VFA, sintesis protein mikroba, total produksi gas dan produksi gas metan, tetapi berpengaruh nyata terhadap konsentrasi NH3. Penambahan urea-nitrat dengan penyalut pati singkong dapat menurunkan konsentrasi amonia dan tidak berdampak terhadap fermentasi, kecernaan rumen dan produksi gas metan., This research aimed to evaluate the effect of starch polymer coating techniques carried out in vitro on urea-nitrate as a feed additive for ruminants. This study used a randomized block design (RBD) with 5 treatments and 4 groups. The treatment consisted of P0 = control ration; P1 = P0 + uncoated urea; P2 = P0 + uncoated urea-nitrate; P3 = P0 + urea-nitrate with sago starch coating; P4 = P0 + urea-nitrate with cassava starch coating. Observed parameters were dry matter digestibility (DMD), organic matter digestibility (OMD), pH, volatile fatty acids (VFA), ammonia concentration (NH3), microbial protein synthesis, total gas production and methane production. The results showed that the treatment ration had no significant effect (P>0.05) on DMD, OMD, pH, VFA, protein synthesis microbes, total gas production and methane production, but had a significant effect on NH3 concentrations. The addition of urea-nitrate coating with cassava starch can reduce ammonia concentrations and has no impact on fermentation, rumen digestibility and methane gas production.
Keyword: ammonia, coating urea-nitrat, in vitro, methane, starch

Judul: Fermentability and Digestibility of Feed Added Slow Relase Urea-Nitrate In Vitro.
Abstrak: Penelitian ini bertujuan menguji pengaruh penambahan slow release urea-nitrat dalam ransum secara in vitro. Penelitian ini menggunakan rancangan acak kelompok 5 perlakuan dan 4 ulangan. Perlakuan terdiri dari P0 = ransum kontrol; P1 = P0 + urea; P2 = P0 + urea-nitrat; P3 = P0 + urea-nitrat dilapisi dengan molases; P4 = urea-nitrat dilapisi dengan limbah cair sari kurma. Peubah yang diamati adalah kecernaan bahan kering (KcBK), kecernaan bahan organik (KcBO), konsentrasi amonia (NH3), derajat keasaman (pH), volatile fatty acid (VFA) total, sintesis protein mikroba (SPM), total produksi gas, dan gas metan. Data dianalisis menggunakan analysis of variance (ANOVA) dan perlakuan yang berbeda nyata akan dilakukan uji lanjut dengan uji duncan menggunakan statistical product and service solutions (SPSS) 25. Hasil penelitian menunjukkan bahwa perlakuan tidak berpengaruh nyata (P>0,05) terhadap nilai KcBK, KcBO, VFA total, pH, SPM, total produksi gas, dan gas metan. Perlakuan yang berpengaruh nyata (P<0,05) adalah konsentrasi amonia (NH3). Simpulan penelitian ini adalah penambahan slow release urea-nitrat belum mampu menurunkan konsentasi amonia., This study aimed to examine the effect of the addition slow release urea-nitrate in rations in vitro. This study used a randomized block design with 5 treatments and 4 replications. The treatment consisted of P0 = control ration; P1 = P0 + Urea; P2 = P0 + urea-nitrate; P3 = P0 + urea-nitrate coated with molasses; P4 = urea-nitrate coated with palm juice liquid waste. The observed variables were dry matter digestibility (KcBK), organic matter digestibility (KcBO), ammonia concentration (NH3), degree of acidity (pH), total volatile fatty acid (VFA), microbial protein synthesis (SPM), total gas production, and methane gas. Data were analyzed using analysis of variance (ANOVA) and significantly different treatments would be further tested with Duncan's test using statistical product and service solutions (SPSS) 25. The results showed that the treatment had no significant effect (P>0.05) on the KcBK, KcBO, total VFA, pH, SPM, total gas production, and methane gas. The treatment that had a significant effect (P<0.05) was the concentration of ammonia (NH3). The conclusion of this study was the addition of slow release urea-nitrate has not been able to reduce the concentration of ammonia.
Keyword: ammonia concentration, in vitro, methane gas, slow release urea-nitrate

Judul: Penggunaan Teorema Homeomorphy 2-Manifold dan Teorema Euler Poincare pada Torus 𝑇�� dan Simplicial Complex 𝐾��
Abstrak: Two dimensional topological spaces are said to be homeomorphic if they have the same topological invariant, where one of topological invariant used is an Euler characteristic. Homeomorphy 2-Manifold’s Theorem and Euler Poincare’s Theorem are used to distinguish two topological spaces. Homeomorphy 2-Manifold’s Theorem uses Euler characteristic to identify two dimensional topological spaces. Euler Poincare’s Theorem is an alternative way to find Euler characteristic with Betti number, which is topological invariant as well. The objective of this paper is to investigate the homeomorphism of torus 𝑇����� and simplicial complex 𝐾�����. Topological space torus and simplicial complex 𝐾����� have the same Euler characteristic, which is two. Based on Homeomorphy 2-Manifold’s Theorem topological space torus 𝑇����� and simplicial complex 𝐾����� is homeomorphic.
Keyword: simplicial, torus, Euler, homeomorphism, topology