Judul: Uji Mikroskopik Kristal Urin pada Sapi Pejantan Bibit dengan Body Condition Score 4–5
Abstrak: Bull, which have role as sperm producer, needs a routine health maintenance for optimal production. Microscopic examination of urine crystals could be used for estimating obstructive urolithiasis in urinary tract. The objectives of this study was to observe urine crystal in 4–5-scored body condition score (BCS) bull. The 30 urine samples of 3 bull breeds (Brahman n=10, Simmental n=10, and Friesian Holstein n=10) were collected, urine pH measure with striptest urinalysis, and urine crystal microscopically examined. Result of this study indicated that all samples were totally positive for crystal. Observed crystals were dominated by struvite (73.3%), while the others were calcium carbonate (23.3%) and phosphate amorph (3.3%). The three form of struvite could be seen octahedral, twin, and penetrated struvite. The different form of struvite indicated level of urine pH and incubation period. Crystalluria phenomenon suggested a low ratio of Ca:P in mineral nutrient and it should be cautious for existing obstructive urolithiasis.
Keyword: Bogor Agricultural University (IPB), urine crystal, struvite, crystalluria, calcium carbonate, bull

Judul: Total dan Diferensiasi Leukosit Sapi Pejantan Unggul dengan Body Condition Scoring (BCS) Tinggi
Abstrak: Bull were sperm producer for artificial insemination. Physiological data such as leukocytes differentiation were important for supporting routine health monitoring. The objective of this study is to get the profile of leukocytes from high-level body condition scoring (BCS) of bull. The 30 blood samples of 3 breed bull (Simmental, Brahman, Friesian Holstein) were collected through coxygeal vein and calculated using microscope eye-piece camera instrument. The results showed that bull in A group (age <5 years) had higher total leukocytes than bull in B group (age >5 years). Average value of total leukocytes, eosinophil, neutrophil, basophil, lymphocyte, and monocyte of bull in A group were 7764 cell/μL, 411 cell/μL, 4150 cell/μL, 109 cell/μL, 2892 cell/μL, and 204 cell/μL consecutively. While the average value of total leukocytes, eosinophil, neutrophil, basophil, lymphocyte, and monocyte of bull in B group were 6832 cell/μL, 437 cell/μL, 3771 cell/μL, 71 cell/μL, 2363 cell/μL, and 192 cell/μL consecutively. Leukocytes morphology between breed and ages also shown the similar shape.
Keyword: Bogor Agricultural University (IPB), high-level bcs, leukocyte differentiation, bull

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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