Judul: Identifikasi Produktivitas Induk Domba yang Digembalakan sebagai Dasar Kriteria Seleksi di Unit Pendidikan Penelitian dan Peternakan Jonggol Institut Pertanian Bogor (UP3J-IPB).
Abstrak: Local sheep is one of the animal genetic resources which is potential to be developed in supporting national meat supply. Local sheep has some superiorities such as twinning birth, early mature age and non seasonally breeding. Nevertheless, instead of these superiority, some problem still occurred as lacking of lamb survivability rate, low carcass percentage and high variances both genotype and phenotype parameters. The objectives of this study were to find the relationship between ewe age and its productivity, and ewe body measurements and its milk yield on grazing system. This study was conducted in the Jonggol Animal Science Teaching and Research Unit (JASTRU), Singasari Village, Bogor District, from June up to November 2007. As many 100 lactating ewes, on 1 to 4 years of age, were used in this study. Sheep were reared on grazing system from 9 a.m. to 4 p.m. and housed at night. The results showed that ewe age highly significant affected the body weight after lambing (p<0,01), milk yield (p<0,01), total birth weight (p<0,01) and total weaning weight (P<0,01) but did not significant for litter size. Breast circle, udder base circle, and udder height showed strong relationship in predicting 3 to 5 year ewe milk yield (p<0,01). The most productive ewes was 3 to 4 year ewes group.
Keyword: Sheep, udder size, milk yield, Weaning weight

Judul: Studi Morfometrik Domba Lokal Jantan Di Unit Pendidikan Dan Penelitian Peternakan Jonggol Sebagai Kriteria Seleksi
Abstrak: Jonggol local sheep is very potential to be developed at Jonggol Animal Science Teaching and Research Unit (JASTRU). The sheep have been well adapted to marginal environments including hot and dry weather, ectoparasites, and limited feed supply. However their growth rate performances still vary among the sheep. It is therefore selection needs to be conducted to get fast growing sheep. Daily gain was used as a standard of differing fast growing sheep and slow growing sheep. Sheep with daily gain above 100gr/head/day was categorized as fast growing sheep and daily gain under 80gr/head/day as the slowing group. The results show that shoulder height, body length, chest circumference, upper neck circumference, lower neck circumference, head length, and mouth circumference were significantly higher at fast growing sheep than slow growing group. Similar results were found that circumference of right foreleg and left upper hind leg, and circumference of hind pastern either at left or right sides were significantly higher at fast growing sheep than slow growing group. This may indicate that the parameters can be used as selection criteria for fast growing sheep. and the parameters can be used as selection criteria to obtain fast growing sheep. On the contrary, chest depth, neck length, tail length, circumference of left foreleg and right upper hind leg, and circumference of neck to thoracic limb and hind pastern either at left or right sides were similar between the two groups of sheep, indicating the three parameters might not be used as the selection criteria. Almost all parameters had positive correlation between one and the other parameters especially daily gain.
Keyword: 

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.
Keyword: