Judul: Synchrony index of releasing N-protein and energy in the rumen as a basis of ruminant diet formulation with local feedstuffs
Abstrak: The experiments were conducted to prove the diet formulation technique which was based on the synchronization of releasing N-protein and energy in addition to energy and protein requrement in diet for efficiency of rumen microbial N synthesis and animal production. Exp. 1. Nylon bag technique was adopted to determine ruminal characteristic of protein and organic matter (OM) degradation of feedstuffs (forage and concentrate diet) for which the synchrony index of N-protein and OM fermented in the rumen might be determined based on synchronization ratio of 20 (I20), 25 (I25), and 30 g N/kg OM (I30) fermented in the rumen. Exp. 2. By using randomized block design, twelve local cattle were arranged into four groups according to average body weight of the animals. Each group was fed three types of diet that was different in synchronization ratio of supplying N-protein and fermented OM in rumen, namely 20 g N/kg OM (R20); 25 g N /kg OM (R25); and 30 g N /kg MO (R30). The diets had iso-energy and iso-protein contents and had the same synchrony index. Exp 3. By using randomized block design with a factorial of 3 x 2. The first factor was three diferent protein levels i.e. 10, 12, and 14 %; the second factor was two deferent levels of TDN (total digestible nutrients) (65 and 70 %). Eighteen local cattles were arranged into three groups according to average body weight of the animals. Each group was fed six types of diet that was different in level of CP or TDN. The diets had the same synchrony index, namely 0,560.
Keyword: N retention, intake of nutrients, digestibility of nutrients, blood urea nitrogen (BUN), rumen microbes

Judul: Reformulation of Dairy Cattle Concentrated Based on  RDP:RUP Balance at Different Energy Level: An In Vitro Study
Abstrak: Produktivitas ternak ruminansia yang efisien membutuhkan protein, tingkat energi dan rasio RDP:RUP dalam pakan yang seimbang. Pakan harus menyediakan nitrogen yang cukup (RDP) untuk pertumbuhan mikroba rumen, serta sebagai sumber protein langsung untuk hewan inang (RUP). Penelitian ini bertujuan untuk mengetahui tingkat optimal rasio RDP:RUP dan tingkat energi ransum sapi perah dengan metode in vitro. Sumber inokulum rumen diperoleh dari rumen fistulasi sapi Friesian Holstein. Perlakuan terdiri dari 4 level rasio RDP: RUP, yaitu 45:55, 50:50, 55:45 dan 60:40, sedangkan level energi terdiri dari level TDN 65%, 70% dan 75%. Rancangan percobaan adalah rancangan acak kelompok pola faktorial. Analisis data menggunakan uji ANOVA dan Duncan multiple range test. Hasil penelitian menunjukkan rasio RDP: RUP dan variasi TDN berpengaruh terhadap KCBK, KCBO, NH3. Kandungan TDN yang lebih tinggi meningkatkan KCBK, KCBO, dan VFA total secara signifikan. Peningkatan imbangan RDP (dari 45% hingga 60%) dan level TDN (low to high) meningkatkan kecernaan nutrisi, kadar VFA total, populasi bakteri dan protozoa. Peningkatan ini menunjukkan bahwa manfaat dari pakan yang berbasis imbangan RDP:RUP dapat meningkatkan produktivitas ternak ruminansia., Efficiency of ruminant productivity requires optimal protein, energy levels, and RDP:RUP ratios in feed. Dairy feed must provide adequate of nitrogen (RDP) for the rumen microbe, as well as a direct protein source for host animals (RUP). This study aimed to determine the optimal RDP:RUP ratio at different energy level of dairy cattle rations using in vitro method. The source of rumen inoculum was obtained from rumen fistulated Friesian Holstein cattle. The treatments consisted of two factors. The factors were 4 RDP:RUP ratios (60:40; 55:45; 50:50; 45:55) and 3 TDN levels (65%; 70%; 75%). The experimental design was a factorial randomized block design. Data were analysed using ANOVA and Duncan’s multiple range test. The result showed that the ratio of RDP:RUP and level TDN had effects on DMD, OMD, NH3. Increased RDP balance (from 45% to 60%) and TDN level (low to high) improve nutrient digestibility, total VFA, bacterial population and protozoa. This increase indicates that the benefits of based feed RDP:RUP balance can increase the productivity of ruminants.
Keyword: n vitro, rumen degradable protein, rumen fermentation, total digestible nutrient

Judul: Cycle Hamilton pada Graf Lengkap, Graf Regular, dan Graf 2-Connected 4-Regular Berorder Kurang dari Sepuluh.
Abstrak: Suatu graf disebut graf Hamilton apabila graf tersebut memuat cycle Hamilton, yaitu cycle yang melewati setiap vertex tepat satu kali. Menentukan keberadaan cycle Hamilton pada suatu graf dapat menggunakan syarat cukup yang berupa teorema-teorema yang telah diperkenalkan sejak tahun 1950-an. Beberapa syarat cukup yang dibahas dalam karya ilmiah ini adalah syarat cukup yang berhubungan dengan graf lengkap dan graf regular. ,,,
Keyword: graf Hamilton, graf regular, graf lengkap, graf 2-connected 4-regular.