Judul: Uji kualitas silase singkong utuh (Manihot esculenta) dengan beda umur panen secara in vitro sebagai upaya peningkatan pemanfaatan pakan lokal
Abstrak: A study to evaluate whole cassava crop silage quality at several age of harvesting compared to total mixed ration have been done. Two kg of well mixed sample of whole crop cassava at 7 month (SSU7), 8 month (SSU8), 9 month (SSU9) of harvesting and sample of total mixed ration (SRK) were ensiled for 5 weeks anaerobically in 35 cm x 50 cm polyvinyl bags silo. Comparison of the silages qualities were based on physical (color, smell, humidity, texture and presence of moulds), fermentative (pH, DM, VFA, DM losses, CP, N-NH3, degradation of CP, WSC, HCN, and fleigh number) and utilities (in vitro rumen fermentability and digestibilities) characteristics. The treatments were completely randomized and each treatment was repeated thrice. Physical, fermentative and utilities characteristics of whole cassava crop silage made from cassava crops harvested at 7, 8, and 9 months of age were comparable to the total mixed ration silage or even better. The best whole crop cassava silage quality was produced from SSU8 (better physical characteristics, higher fleigh number, and digestibilities). However, because of nutritional contents of whole cassava crop were changed with age, therefore the silage utilization should consider animal requirement and its level of inclusion.
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Judul: Kualitas Silase Tanaman Jagung Pada Berbagai Umur Pemanenan
Abstrak: The objective of this 5 months research was to determine the optimum harvest time of corn, through the physical, fermentative, and utility characteristics of its whole-plant corn silage. Corns (Zea mays L) with different age (60 d,70 d,80 d, and 90 d) were respectively harvested and separated by each part (Leave, stalk, cob, kernel, and husk). Those parts were chopped (± 2cm) and mixed afterwards. The amount of 2 kg of total mixed corn-plants were placed in plastic silo then ensiled for 5 weeks. Whole plant corn silage would be compared with total mixed ration silage. Descriptive analysis of physical characteristics resulted indifferent for each silage. Completely randomized design was used to analyze the fermentative data, showed DM content increase but CP and WSC concentrations decrease as age advanced. After ensiling, silages produced less DM losses and ammonia nitrogen, indicated fermentation run well. Lower concentration of VFA can be explained by lower soluble fermentation of lactate acid bacteria during ensilage. In vitro technique were used to evaluate silage as diets in rumen by measure the VFA & NH3 rumen, DM & OM digestibility. Ammonia in rumen were greater at early age than advanced age whereas VFA concentrations showed insignificant. DM and OM digestibility at 90d silage resulted the highest digestibility. The results showed that 80d corn silage was the optimum age of harvest.
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Judul: Metrik Einstein (Anti-) Self-Dual Berdimensi Empat dengan Metode Cartan
Abstrak: Gravitational field equation can be formulated in differential forms (differential geometry), which describes gravity as a manifestation of the curvature of space-time. Curvature of space-time is characterized by a metric that satisfies the gravitational field equation. With differential forms it can be formulated the (anti-) self-dual Einstein equation, which is a modification of the Cartan structure in (anti-) self-dual basis. Calculation of (anti-) self-dual metric with (anti-) self-dual Einstein equation is simpler than the calculation using Christoffel symbols.
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