Judul: Performa ayam broiler yang diberi hormon testosteron dengan dosis bertingkat
Abstrak: Testosterone is a hormone that has an important role in secondary sex characteristics. Testosterone was known as androgenic and anabolic hormone. This research used testosterone to observe the performance of broiler chickens. Fourty four broiler chickens 15 days old were divided into 4 groups: K (control), T1 (dose 1 mg), T2 (dose 2 mg), and T3 (dose 4 mg). Parameters measured were body weight, feed and water consumption, feed conversion ratio (FCR), and mortality. The results showed that testosterone dose 1 and 4 mg could increase the daily body weight gain significantly (p<0.05) in broiler chickens aged between 15 and 18 days old. Testosterone dose 2 mg could increase the daily body weight gain significantly (p<0.05) in broiler chickens aged between 21 and 24 days old. Final weight, the amount of feed and water consumption, feed conversion ratio (FCR), and mortality of chickens given testosterone did not show any difference compare with control.
Keyword: broiler, daily body weight gain, FCR, final weight, testosterone

Judul: Gambaran Kecernaan Pakan Ayam Broiler yang diberi Testosteron dengan Dosis Bertingkat
Abstrak: Testosterone is one of the anabolic hormone that can trigger the growth of muscle mass as well as develop and maintain bone. Testosterone hormone can stimulate secretion of other hormones such as growth hormone. This research was conducted to describe the administration of testosterone hormone with multilevel concentration on broiler chicken’s feed digestibility through feces analysis. Fourteen days of twenty broiler chickens were used in this experiment, with 4 groups (K, T1, T2, and T3). K was control groups, T1, T2, and T3 were broiler chicken which given 1, 2, and 4 mg testosteron respectively. Feces is waste of metabolism which can be used for proximate analysis. Feed digestibility values was obtained from the difference percentage between the value of proximate analysis of feed and feces which divided by the value of the proximate analysis of feed. The highest digestibility values of fat (79.20%), protein (65.37%), and carbohydrates (69.79%) was in T3 groups. Therefore administration of 4 mg testosterone could increase the body weight.
Keyword: digestibility, feces, hormones, proximate, testosterone.

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.
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