Judul: Karakteristik Fermentasi Rumen In vitro dengan Penambahan Sabun Kalsium Minyak Nabati pada Buffer yang Berbeda.
Abstrak: Supplementation of unsaturated fatty acid source from plant in ruminant feed is needed to improve the production and quality of beef meat. Canola oil and flaxseed oil are vegetable oils as potential sources of unsaturated fatty acid. However, to use vegetable oils as sources of unsaturated fatty acids, need to be protected to avoid biohydrogenation by rumen bacteria. The experiment was conducted in a factorial randomized block design with 2 factors and 3 blocks based on rumen sampling time. The first factor was sources of vegetable oils (canola and falxseed) and the second factor was kind of buffer ( Kajikawa and Mc.Dougall). Variables observed were pH value, N-NH3 concentration, total volatile fatty acid (VFA), dry matter and organic matter digestibility. The result showed that there was no interaction between sources of diet and buffer. Supplementation of canola and flaxseed oils protected by calcium soap at level 6% did not affect pH value, dry matter digestibility, rumen protozoa and total bacteria. The use of different buffers affected pH value, dry matter digestibility, rumen protozoa and total bacteria.
Keyword: canola oil, fermentation, flaxseed oil, NH3, VFA

Judul: Supplementation on Digestibility and In Vitro Fermentability of Dairy Cattle Rations
Abstrak: Penelitian ini bertujuan untuk menguji minyak kanola, kedelai dan sawit terproteksi sabun kalsium (Ca Soap) secara in vitro. Penelitian ini menggunakan Rancangan Acak Kelompok (RAK) dengan 4 perlakuan dan 3 ulangan: P1 (kontrol tanpa perlakuan), P2 (P1+1% Ca Soap), P3 (P1+2% Ca Soap), dan P4 (P1+3% Ca Soap). Variabel yang diamati meliputi karakteristik fermentasi rumen (pH, konsentrasi volatile fatty acid (VFA) total, konsentrasi ammonia), kecernaan bahan kering dan bahan organik, dan aktivitas mikroba rumen. Data dianalisis dengan menggunakan Analysis of Varian (ANOVA) dan perlakuan yang berbeda nyata akan dilakukan uji lanjut dengan Uji Tukey menggunakan program Minitab 18. Hasil penelitian menunjukkan bahwa perlakuan tidak berpengaruh nyata (P>0,05) terhadap pH, konsentrasi ammonia (NH3), Kecernaan Bahan Organik (KCBO). Jenis minyak juga berpengaruh terhadap Kecernaan Bahan Kering (KCBK). Terdapat interaksi pada perhitungan populasi bakteri dan VFA. Penggunaan minyak nabati terproteksi yaitu minyak kanola, kedelai dan sawit 3% menunjukkan hasil optimal pada fermentabilitas dan kecernaan serta masih berkisar normal., This research aims to test canola, soybean and palm oils protected by calcium soap (Ca Soap) in vitro. This study used a randomized block design with 4 treatments and 3 replications: P1 (control without treatment), P2 (P1+1% Ca Soap), P3 (P1+2% Ca Soap), and P4 (P1+3% Ca Soap). The variables observed included rumen fermentation characteristics (pH, total volatile fatty acid (VFA) concentration, ammonia concentration), dry matter and organic matter digestibility, and rumen microbial activity. Data were analyzed using the Analysis of Variance (ANOVA) and significantly different treatments would be further tested with the Tukey test using the Minitab 18 program. The results showed that the treatment had no significant effect (P>0,05) on pH, concentration of ammonia (NH3), digestibility of organic matter. The type of oil also affects the digestibility of the dry matter. There is an interaction in the calculation of the bacterial population and VFA. The use of protected vegetable oils, namely canola, soybean and palm oil at a level of 3% showed optimal results in rumen fermentability and digestibility and were still in the normal range.
Keyword: Ca soap, canola oil, fermentability, in vitro, palm oil, soybean oil

Judul: Closed Knight’s Tour pada Papan Catur Berbentuk Persegi Panjang dengan Ukuran Maksimal 8 × 8
Abstrak: Closed Knight’s Tour merupakan langkah kuda yang mengunjungi setiap kotak pada papan catur tepat satu kali dengan langkah kuda berawal dan berakhir pada kotak yang sama. Graf yang terbentuk dari closed knight’s tour dinotasikan sebagai graf G(m,n), dengan m adalah banyaknya baris dan n adalah banyaknya kolom. Graf tersebut memuat Hamiltonian cycle. Sebuah graf terhubung G adalah graf bipartite jika dan hanya jika graf tersebut tidak memiliki cycle dengan panjang ganjil. Papan catur yang memenuhi syarat cukup untuk memiliki closed knight’s tour adalah papan catur berukuran 5 × 6, 5 × 8, 6 × 6, 6 × 7, 6 × 8, 7 × 8, dan 8 × 8.
Keyword: bipartite, closed knight’s tour, hamiltonian cycle, knight’s tour, teori graf