Judul: Performance and Nutrient Digestibility of Sheep and Goat Fed Gamal Leaves with Various Processing Methods (Quantitative Study)
Abstrak: Pengaruh penambahan daun gamal dalam ransum domba dan kambing terhadap peforma dan kecernaan memiliki hasil beragam. Studi kuantitatif dilakukan untuk mengkaji hubungan level pemberian daun gamal dalam ransum domba dan kambing terhadap peforma dan kecernaan ternak dengan model regresi non-linear sederhana. Sebanyak 28 artikel jurnal nasional dan internasional terkait penggunaan daun gamal pada ternak domba dan kambing digunakan sebagai sumber data pada kajian ini. Analisis data dilakukan dengan menggunakan Microsoft Excel 2010 dan IBM SPSS 25. Hasil studi kuantitatif menunjukkan penambahan daun gamal dalam bentuk tepung pada ransum domba nyata (P<0,05) meningkatkan konsumsi bahan kering (KBK) ransum dan pertambahan bobot badan (PBB). Penambahan daun gamal dalam bentuk silase pada ransum domba tidak nyata (P>0,10) meningkatkan PBB, KBK ransum, efisiensi pakan, kecernaan bahan kering (KcBK), dan kecernaan bahan organik (KcBO). Pada kambing penambahan daun gamal dalam bentuk tepung ransum kambing tidak nyata (P>0,10) PBB, efisiensi pakan, KcBK, dan KcBO. Penambahan daun gamal dalam bentuk silase ransum pada kambing nyata (P<0,05) meningkatkan KcBO ransum, tidak nyata (P>0,10) mempengaruhi PBB, KBK, efisiensi pakan, dan KcBK. Dapat disimpulkan bahwa level optimum penggunaan daun gamal dalam bentuk tepung untuk ransum domba adalah sebesar 77,76%., The effect of utilizing gliricidia leaves on sheep and goats’ performance and digestibility has various results. This review aimed to quantitatively study the relationship among performance, digestibility, and level of gliricidia leaves used in small ruminant feed with a simple non-linear regression model. A total of 28 national and international journal articles related to the use of Gamal leaves in sheep and goats were used as data sources in this study Data were analyzed using Microsoft Excel 2010 and IBM SPSS ver.25. The result showed feeding gliricidia leaves meal to sheep increased (P<0,05) dry matter (DM) intake and body weight gain (BWG). Feeding gliricidia leaves silage to sheep did not have a significant effect (P>0,10) on BWG, DM intake, efficiency, DM digestibility, and organic matter (OM) digestibility. Feeding gliricidia leaves meals to goats did not have a significant effect (P>0,10) on BWG, efficiency, DM and OM digestibility. Feeding gliricidia leaves silage to goat increased (P<0,05) on OM digestibility, but not a significant effect (P>0,10) on BWG, DM intake, efficiency, and DM digestibility. The optimum level of gliricidia leaves meal on sheep is 77.76%.
Keyword: goats, gliricidia leaves, performance, sheep

Judul: Performa Ruminansia Kecil yang Diberi Daun Singkong (Manihot  esculenta) dengan Pengolahan Berbeda : Kajian Pustaka
Abstrak: Daun singkong tersedia secara melimpah dan mempunyai kandungan protein kasar yang cukup tinggi yaitu berkisar 20%. Pemanfaatan daun singkong terkendala dengan zat anti nutrien yang terkandung di dalamnya yaitu asam sianida sehingga perlu adanya teknologi dan upaya pengolahan seperti pembuatan silase atau pengeringan. Penelitian ini bertujuan menganalisis performa ruminansia kecil yang diberi pakan daun singkong dengan pengolahan berbeda dengan pendekatan review kuantitatif, sebanyak 32 literatur dari tahun 2010-2020 diperoleh 72 data perlakuan yang ditabulasi pada microsoft excel 2019. Parameter pada penelitian dilakukan dengan uji deskriptif dan menggunakan uji regresi linier serta kuadratik. Parameter tersebut meliputi pertambahan bobot badan, konsumsi bahan kering, kecernaan bahan pakan, dan efisiensi pakan. Hasil analisis regresi menunjukan bahwapemberian pakan daun singkong dengan olahan kering pada taraf 50% meningkatkan pertambahan bobot badan (P≤0,05, R2 = 0,195) dan kecernaan bahan organik pada taraf daun singkong 60% (P≤0,01, R2 = 0,528). Pemberian pakan daun singkong dengan olahan silase pada ternak ruminansia kecil pada taraf 60% menurunkan konsumsi bahan kering (P≤0,01, R2 = 0,807). Efisiensi pakan relatif sama dengan pemberian daun singkong kering maupun dalam bentuk silase. Daun singkong olahan kering dapat digunakan sebagai campuran pakan ruminansia kecil dengan taraf pemberian optimal sebesar 60%, sedangkan olahan silase dapat diberikan dengan taraf optimal 20%., Cassava leaves are available in abundance amount and contain of 20% crude protein. Utilization of cassava leaves is constrained by the anti-nutritional content, cyanide acid. This toxic compound needs to be reduced using processing such as silage or drying. This study aims to analyze the performance of small ruminants fed cassava leaves with different processing with a quantitative review approach. The study using 32 national or international journal articles from 2010-2020. The data was tabulated in Microsoft Excel 2019. The body weight gain, dry matter intake, feed digestibility, and feed efficiency were measured in this study. Those variable measured were analyze using by descriptive analysis and regression tests with linear and quadratic approach. The results of the regression analysis showed that feeding dry-processed cassava leaves at a level of 50% increased body weight gain (P≤0.05, R2 = 0.195) and organic matter digestibility at a level of 60% cassava leaves (P≤0.01, R2 = 0.528). Feeding cassava leaves silage to small ruminants at a level of 60% decreased dry matter consumption (P≤0.01, R2 = 0.807). The feed efficiency was similar among treatments. The dry-processed cassava leaves can be used as a mixture of feed for small ruminants with an optimal feeding rate of 60%, while the processed silage can be used at optimal level of 20%.
Keyword: cassava leaves, drying, ruminants, silage

Judul: Hamiltonian formulation for linear waves motion in two layers fluid
Abstrak: The surface wave could be considered as a wave that separates two fluids, namely water and air. Based on this assumption, it is introduced the interfacial wave, a wave between two layers of fluid with different density. The formulation of interfacial waves motion begins with deriving the base equation of irrotational ideal fluid. Furthermore, according to irrotational fluid assumption, the base equation can be stated in velocity potential. In this derivation, the fluids domain is assumed to be restricted by rigid lid boundary conditions, both at the upper and lower limit. Therefore, the interfacial waves motion can be explained in a hamiltonian formulation. In the hamiltonian formulation, total energy is defined as the sum of kinetic and potential energy. The hamiltonian system is obtained from reduction of kinetic energy by using the Dirichlet Neumann Operator. The resulted kinetic energy equation is nonlinear. Therefore, this form is linearized by first part of the Taylor expansion. This linearization gives a dispersion relation of linear wave. Based on this dispersion relation, the phase speed of the linear wave depends on the density ratio of the two layers fluid.
Keyword: