Judul: Effect of Lactobacillus plantarum Probiotic Supplementation on Cattle Rumen Fermentability and Methanogenesis: Quantitative Studi
Abstrak: Penelitian ini bertujuan mengetahui efek suplementasi Lactobacillus plantarum terhadap fermentabilitas dan metanogenesis rumen pada ternak ruminansia dengan mengintegrasikan data dari berbagai studi terkait dan menggunakan model matematis analisis regresi. Peubah yang diamati dalam penelitian ini antara lain total gas, emisi metana, pH, NH3, populasi bakteri dan total VFA. Data diolah secara analisis deskriptif dan analisis regresi linier sederhana. Suplementasi probiotik Lactobacillus plantarum mampu meningkatkan jumlah produksi gas, total VFA dan beberapa produk VFA parsial meliputi propionate dan butirat, sehingga hal ini dapat menunjukkan bahwa penggunaan Lactobacillus plantarum mampu mengefisienkan proses fermentasi pakan di dalam rumen. Suplementasi probiotik Lactobacillus plantarum berpengaruh menurunkan jumlah produksi gas metan (CH4) dan proporsi asetat dalam rumen yang berasosiasi terhadap penurunan rasio asetat:propionat dalam rumen. Kata kunci : bakteri asam laktat, fermentabilitas, Lactobacillus plantarum, metanogenesis, rumen., This study aimed to determine the effect of Lactobacillus plantarum supplementation on rumen fermentability and methanogenesis in ruminants by integrating data from various related studies and using a mathematical model of regression analysis. The observed variables were total gas, CH4, pH, NH3, number of bacterial microbes and total VFA. The data was processed by descriptive statistics and simple linear regression test. The probiotic supplementation of Lactobacillus plantarum was able to increase the amount of gas production, total VFA and some partial VFA products including propionate and butyrate, so this could indicate that Lactobacillus plantarum utilization were able to streamline the feed fermentation process in the rumen. Supplementation of probiotic Lactobacillus plantarum had an effect on reducing the amount of methane gas production (CH4) and the proportion of acetate in the rumen which was associated with a decrease in the ratio of acetate:propionate in the rumen. Keywords : fermentability, methanogenesis, lactic acid bacteria, Lactobacillus plantarum, rumen
Keyword: Bakteri Asam Laktat, Fermentabilitas, Lactobacillus plantarum, Metanogenesis, Rumen

Judul: Effects of Megasphaera elsdenii Probiotic Supplementation on the Fermentability and Concentration of Rumen Lactic Acid in Preventing Acidosis
Abstrak: Megasphaera elsdenii adalah spesies pengguna laktat yang menonjol dalam rumen. Penggunan M. elsdenii sebagai probiotik karena kemampuannya dalam memanfaatkan laktat, sehingga menurunkan akumulasi laktat dalam rumen dan menstabilkan pH. Penelitian ini dilakukan untuk mengevaluasi penggunaan M. elsdenii secara in vivo terhadap fermentasi rumen dan konsentrasi asam laktat dalam mencegah asidosis pada ternak, dengan mengintegrasikan data dari berbagai studi terkait menggunakan model matematis analisis regresi. Sebanyak 15 studi diperoleh 66 data. Parameter meliputi konsentrasi asam laktat, produk fermentasi, dan populasi mikroba rumen. Data dianalisis menggunakan analisis regresi dengan software IBM SPSS versi 20. Hasil analisis menunjukkan bahwa suplementasi probiotik M. elsdenii memberikan efek penurunan signifikan (P<0.05) terhadap konsentrasi asam laktat, proporsi asetat, rasio asetat:propionat, dan cenderung signifikan terhadap penurunan metan (P<0.1). Selain itu, suplementasi M. elsdenii juga berpengaruh sangat signifikan (P<0.01) terhadap peningkatan total VFA dan proporsi butirat, serta berpengaruh secara signifikan (P<0.05) terhadap peningkatan proporsi propionat, proporsi isobutirat, dan cenderung signifikan (P<0.1) terhadap peningatan proporsi valerat. Namun pemberian probiotik M. elsdenii ini tidak berpengaruh signifikan (P>0.10) terhadap pH, NH3, proporsi isovalerat, dan populasi protozoa di dalam rumen. Dapat disimpulkan bahwa suplementasi probiotik M. elsdenii secara in vivo terbukti mampu menurunkan konsentrasi asam laktat dan meningkatkan beberapa produk hasil fermentasi rumen., Megasphaera elsdenii is a lactate utilizing species that predominates in the rumen. The use of M. elsdenii as a probiotic is due to its ability to utilize lactate, thereby reducing the accumulation of lactate in the rumen and stabilizing pH. This study was conducted to evaluate the use of M. elsdenii in vivo to rumen fermentation and lactic acid concentration in preventing acidosis in livestock, by integrating data from various related studies using a regression analysis mathematical model. A total of 15 studies were obtained that considered of 66 data points. The parameters integrated were lactic acid concentration, fermentation products, and rumen microbial populations. The data were subsequently analyzed by using a regression analysis and employed IBM SPSS version 20 statistical software. Results revealed that probiotic supplementation of M. elsdenii had a significant reduction effect (P <0.05) on the concentration of lactic acid, proportion of acetate, ratio of acetate: propionate and tended to be significant (P <0.1) on an decrease of methane production. In addition, M. elsdenii supplementation also had a very significant effect (P <0.01) on the increase in total VFA and butyrate proportion, and had a significant effect (P <0.05) on the increase in propionate proportion, isobutyrate proportion, and tended to be significant (P <0.1) on an increase in the proportion of valerate. However, giving probiotic M. elsdenii did not have a significant effect (P> 0.10) on pH, NH3, proportion of isovalerate, and protozoa population in the rumen. It can be concluded that the effect of probiotic M. elsdenii supplementation in vivo is proven to be able to reduce lactic acid concentrations and increase some rumen fermentation products.
Keyword: acidosis, lactic acid, Megasphaera elsdenii, regression analysis

Judul: Thermal Characteristics and Dynamics of Tropical Cyclone over Western North Pacific Ocean: A Case Study of Typhoon Songda (Chedeng) 2011
Abstrak: The frequent occasion of Tropical Cyclone (TC) over Western North Pacific (WNP) Ocean lies from 10˚N to 26˚N and 121˚E to 170˚E. Sources of TC development come from warm ocean temperature where latent heat is released during condensation processes and subsequently concentrated in the boundary layer. Relative humidity at 850-700 hPa is responsible to produce the most intense storm. Meanwhile, weak vertical wind shear between 850-200 hPa is one of the dynamical factors that lead to the development of TC. Pressure level of 850-200 hPa is chosen to minimize the thermodynamic effect in the lower troposphere. Typhoon Songda (Chedeng in the Philippines) or TSC lasted from May 18th to 30th, 2011 and strengthened into powerful Super Typhoon stage between May 24th and 27th. Long curving track and the exhibition of all sequences of TC life cycle, TSC is then considered as an ideal case of TC. The objective of the study with case of TSC is to investigate the role of thermal characteristics and dynamics on TC intensity. The research is carried out by using Advanced Research of Weather Research and Forecasting model (WRF ARW model) version 3.3. Two domains are employed in the model. The first domain situate from 02˚N to 40˚N and 118˚E to 149˚E and cover spatial resolution () of 33.1 km. The second domain situate from 09˚N to 27˚N and 119˚E to 132˚E with of 11 km. Timestep of the model () is 120 seconds. The model is supported by the following physical parameterization, i.e., Yonsei University Scheme (YSU) in the boundary layer, Kain-Fritsch scheme (KF) in the cumulus, and WRF Single-Moment 3-class scheme in the microphysics. Initial meteorological condition prior to the formation of the cyclone is generated using WRF ARW standard-release model. Sensitivity of the model output is obtained from a selected single-parameter change scenarios, namely, 10 % to 20 % decrease and increase of wind shear initial data at 850-200 hPa, and by 10 % to 20 % decrease of relative humidity initial data at 850-700 hPa. The result showed that the negative correlations between wind shear and intensity are found in wind shear scenarios. Wind shears of 10 ms-1 which lead to strengthening of the wind intensity in the early period of Typhoon development are found in wind shear scenarios. The effect of wind shear changes on wind intensity is statistically significant in the 20 % wind shear scenarios. During mature stage, weak wind intensity occurred when wind shear increase as given in the WRF standard-release and the 20 % decreasing scenario. Different situation is found in the 20 % increasing scenario where wind shear tend to weak and lead to strong wind intensity at this stage. Meanwhile, the reduction of moisture supply at 850-700 hPa resulting from 20 % decreasing relative humidity play a major role in the weakening of wind intensity and reduces mechanical energy of the cycle process as much as 300 J kg-1.
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