Judul: Case Study of Nematode Parasite Infection in Dairy Cattle at PT Nusantara  Agri Sejati, Sukaraja District, Sukabumi Regency, Case Study of Nematode Parasite Infection in Dairy Cattle at PT Nusantara Agri Sejati Sukaraja District Sukabumi Regency
Abstrak: Produksi susu di Indonesia masih tergolong rendah. Indonesia hanya mampu memasok 21% kebutuhan susu, sebanyak 79% dipenuhi dari impor. Salah satu perusahaan susu sapi di Indonesia adalah PT Nusantara Agri Sejati. Permasalahan penurunan produksi susu sering diakibatkan oleh gangguan infeksi endoparasit salah satunya cacing nematoda. Manajemen kesehatan yang penting dilakukan yakni pemeriksaan infeksi cacing pada ternak. Data ini sangat penting sebagai acuan untuk melakukan pengobatan atau pengendalian parasit. Penelitian ini bertujuan mengidentifikasi jenis, menghitung prevalensi dan derajat infeksi parasit nematoda, serta mengidentifikasi faktor risiko intrinsik dan ekstrinsik yang berpengaruh terhadap kejadian infeksi nematoda di PT Nusantara Agri Sejati. Data diperoleh dari 34 sampel feses sapi yang diidentifikasi menggunakan metode flotasi dan Mc Master. Hasil pemeriksaan menunjukkan adanya infeksi Nematoda, jenis telur yang teridentifikasi adalah strongylid dan trichurid. Angka prevalensi infeksi mencapai 53% dengan nilai TTGT 108,87. Faktor yang berpengaruh terhadap kejadian infeksi Nematoda di PT NAS adalah faktor risiko ekstrinsik yakni sistem pemeliharaan, pengelolaan limbah feses, sumber dan penyimpanan pakan, program pemberian obat cacing yang tidak berkala, dan kondisi lingkungan., Milk production in Indonesia is still relatively low. Indonesia is only able to supply 21% of its milk needs, 79% of which is met by imports. One of the dairy companies in Indonesia is PT Nusantara Agri Sejati. The problem of decreased milk production is often caused by interference with endoparasite infections, one of which is nematode worms. Health management that is important to do is examination of helminthic infections in livestock. This data is very important as a reference for treating or controlling parasites. This study aims to identify the species, calculate the prevalence and degree of nematode parasite infection, and identify the intrinsic and extrinsic risk factors that influence the incidence of nematode infection at PT Nusantara Agri Sejati. Data were obtained from 34 cow faeces samples identified using the flotation and Mc Master methods. The examination results showed a nematode infection, the egg types identified were strongylid and trichurid. The infection prevalence rate reached 53% with the TTGT value of 108.87. Factors that influence the incidence of nematode infection at PT NAS were extrinsic risk factors, namely rearing systems, faecal waste management, feed sources and storage, occasional deworming programs, and environmental conditions.
Keyword: faktor risiko, manajemen pemeliharaan, nematoda, sapi perah

Judul: Case Study of Cestode Infection in Friesian Holstein Dairy Cattle at PT Nusantara Agri Sejati Sukabumi Regency West Java Province
Abstrak: Sapi Friesian Holstein (FH) merupakan ras sapi dengan sumber susu yang potensial untuk dikembangkan di Indonesia, oleh karena itu diperlukan manajemen pemeliharaan yang baik untuk menghindari penyakit yang bersifat non-genetik seperti infeksi cestoda saluran pencernaan yang dapat mengurangi produktivitas sapi perah. Penelitian ini bertujuan untuk mengukur tingkat kejadian infeksi cestoda dan mengidentifikasi faktor risiko yang berpengaruh terhadap kejadian infeksi cestoda di PT Nusantara Agri Sejati (NAS) Kabupaten Sukabumi Provinsi Jawa Barat. Penelitian ini menggunakan 34 ekor sapi bunting dan muda (dara). Sampel yang dikoleksi berupa feses serta pengambilan sampel rumput dan tanah di empat titik sekitar lahan PT NAS yang digunakan untuk sumber pakan. Analisis data menggunakan uji chi- square untuk mengukur keberadaan hubungan antara variabel dan perhitungan odds ratio untuk mengukur kuat hubungan paparan dengan kejadian penyakit. Hasil penelitian ini menunjukkan infeksi Moniezia sp. dari kelas cestoda di PT NAS rendah dengan prevalensi sebesar 20,5% dan jumlah telur kurang dari 50 TTGT. Faktor risiko BCS memiliki hubungan nyata terhadap infeksi cestoda di PT NAS (p-value 0,029). Infeksi cestoda di PT NAS dipengaruhi oleh faktor Body Condition Score (BCS). Hal ini berhubungan dengan status gizi BCS 2 lebih rentan terkena infeksi cestoda daripada BCS 3. Perbaikan pakan dan program deworming perlu dilakukan untuk menghindari kenaikan kejadian infeksi cestoda di PT NAS., Friesian Holstein (FH) are a breed of cattle with a potential source of milk to be developed in Indonesia, therefore good management is needed to avoid non-genetic diseases such as digestive tract cestode infections which can reduce the productivity of dairy cows. This study aims to determine and measure the incidence of cestode infection and determine factors that can affect the incidence of cestode infection in PT Nusantara Agri Sejati (NAS) Sukabumi Regency, West Java Province. This study used 34 pregnant and young cows (heifers). Samples were collected in the form of feces as well as grass and soil sampling at four points around the PT NAS land used for feed sources. Data analysis used the chi-square test to measure the relationship between exposure and disease and to calculate the odds ratio to measure the magnitude between variables. The results showed that there are infection with Moniezia sp. of the cestode class at PT NAS is very low with a prevalence (20,5%) and the number of eggs is less than 50 TTGT. BCS risk factors have a significant relationship to cestode infection at PT NAS (p-value 0,029). Cestode infections in PT NAS are influenced by Body Condition Score (BCS) factors. This is related to the nutritional status of BCS 2 which is more susceptible to cestode infection than BCS 3. Improvement in feed management and deworming program need to be carried out due to avoid increases incidence of cestode infections in PT NAS.
Keyword: cestoda, faktor risiko, feses, Moniezia sp., sapi perah

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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