Judul: Profil organ dalam Ayam Broiler yang diberi ransum berbasis karbohidrat atau lemak sebagai sumber energi disuplementasi vitamin E dan C melalui air minum
Abstrak: Indonesia sebagai salah satu negara tropis memiliki suhu rata-rata siang hari diatas 30 °C dan kelembaban berkisar diantara 60-90% (BMKG 2010). Hal ini berpeluang menyebabkan kondisi yang kurang nyaman untuk produksi ayam broiler. Kondisi yang cukup panas dan lembab ini menyebabkan penurunan performa dan produksi ayam broiler. Salah satu alternatif pencegah cekaman panas ini adalah penggunaan sumber energi dalam pakan yang lebih efisien dan suplementasi vitamin E dan C. Pakan berbasis karbohidrat sebagai sumber energi akan menghasilkan panas di dalam tubuh yang lebih tinggi dibanding dengan pakan berbasis lemak sebagai sumber energi. Pemberian pakan yang berbeda ini dan suplementasi vitamin E dan C dikhawatirkan dapat menimbulkan kelainan pada organ dalam ayam broiler. Untuk itu pada penelitian ini dievaluasi pengaruh sumber energi yang berbeda pada ayam broiler yang diberi suplementasi vitamin E dan vitamin C melalui air minum terhadap profil organ dalam ayam broiler yang diberi ransum berbasis lemak dan karbohidrat. Penelitian ini dilaksanakan pada bulan Oktober-Desember 2011. Ternak yang digunakan dalam penelitian ini adalah 160 ekor ayam broiler strain Ross dengan rataan bobot badan 42 g/ekor. Vitamin E dan C yang digunakan dicampur dalam bentuk bubuk dengan dosis 1 g/L air minum. Perlakuan pada penelitian ini terdiri atas R1 (pakan berbasis karbohidrat tanpa suplementasi vitamin), R2 (pakan berbasis lemak tanpa suplementasi vitamin), R3 (pakan berbasis karbohidrat dengan suplementasi vitamin), R4 (pakan berbasis lemak dengan suplementasi vitamin). Penelitian ini menggunakan Rancangan Acak Lengkap (RAL). Hasil yang diperoleh kemudian dianalisis dengan sidik ragam ANOVA. Peubah yang diamati adalah presentase bobot organ dalam (jantung, hati, pankreas, ginjal, thymus, dan bursa fabricius) dan bobot dan panjang relatif organ pencernaan (proventrikulus, ventrikulus, usus halus (duodenum, jejenum, ileum), sekum, colon).
Keyword: Giblets, Broiler, Carbohydrate, Lipid, Vitamin E and C

Judul: Metabolisme lemak ayam broiler yang diberi pakan berbasis karbohidrat atau lemak yang disuplementasi vitamin E dan vitamin C melalui air minum.
Abstrak: Indonesia as a tropical country potentially lead to a less comfortable conditions for the production of broiler chickens. Stress conditions can stimulate cell membrane and tissue damage, so it can give a negative impact on the chickens, for example the liver. It is necessary to neutralize (antioxidants) lipid peroxidation and detoxification of toxic metabolic products in an effort to maintain or increase fat metabolism in the liver. Objectives of thus research were to evaluate the vitamin E and C supplementation through drinking water to overcome the existence of free radicals and lipid metabolism in the body. Research used the 160 male Ross broiler strain with weight of 38 ± 2 g with a brand CP 707 (Ross strain). For the first week, the broiler chickens were fed a commercial starter of PT Charoen Pokphand Indonesia, then followed by two types feed namely carbohydrate-based (PC) and fat-based (PL) rations, depend of fat level content in the feed. Vitamin C was given at 60 mg/l of drinking water and vitamin E at 8 mg/l of drinking water of PT Trouw Nutrition Indonesia. Data collection were done for 21 days after the age of 8-28 days with 4 combination treatments, 4 replicates and 10 chickens per replicate. Research using factorial completely randomized design (CRD factorial). The data were analyzed using ANOVA followed by orthogonal contrast test. The data obtained were tested using the General Linear Model procedure using SAS software version 9.1. Some aspects analyzed are the malonaldehid (MDA), blood profile, blood chemistry, apparent metabolize energy, nitrogen retention, fat retention and broiler performance. The results showed that blood profile, blood chemistry, malonaldehid (MDA), relative liver weights and body weight gain were not affected (P > 0.05) due to the treatments. On the other hand total cholesterol (P < 0.01) and HDL cholesterol (P < 0.05) were significantly affected by the treatments. Feed intake and feed conversion ratio significantly different (P < 0.01) caused by interaction of vitamin supplementation through drinking water with fat based rations. In conclusion , fat based rations is more profitable (IOFC) and improve feed conversion ratio of broiler chickens during heat stress when supplemented with vitamin E and vitamin C through drinking
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Judul: Bifurkasi Hopf pada Model Siklus Bisnis Kaldor Kalecki tanpa dan dengan Waktu Tunda
Abstrak: Business cycle model is one of dynamical system models in economic. One of the business cycles model is Kaldor-Kalecki model. Kaldor-Kalecki business cycle model that is written in delayed defferential equations, is a business cycle model that involves gross product and capital stock of a company. In this paper Kaldor-Kalecki business cycle model is analyzed using both nondelay and delay in time of capital stock. By Taylor expansion for the time delayed model, an analysis of stability around the fixed points has been done. Furthermore, by using Hopf bifurcation theorem, it can be shown that there exists periodic orbits and limit cycle. In the nondelayed model, changing the parameter of goods market could lead to the occurrence of Hopf bifurcation and the existence of limit cycle. Similarly, for the delayed model, it has been shown that changing the time delay parameter may result in the occurrence of Hopf bifurcation and limit cycle.
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