Judul: Effect of Injection of Karamunting Melastoma malabathricum Leaf Extract on Sperm Quality of Male Vannamei Shrimp Litopenaeus vannamei Broodstock
Abstrak: Induk udang vaname jantan dengan kualitas sperma yang optimal sangat diperlukan untuk menunjang produktivitas pasokan benih unggul. Salah satu tanaman yang berpotensi untuk meningkatkan kualitas sperma pada udang adalah karamunting (Melastoma malabathricum L.). Penelitian ini bertujuan menguji pengaruh injeksi ekstrak daun karamunting terhadap kualitas sperma induk udang vaname jantan. Induk udang vaname jantan diberi perlakuan dengan diinjeksi akuades sebagai kontrol, serta injeksi ekstrak daun karamunting dengan dosis 7,5 mg/kg bobot tubuh (DK7,5), 10 mg/kg bobot tubuh (DK10,0), dan 12,5 mg/kg bobot tubuh (DK12,5). Injeksi dilakukan setiap lima hari sekali selama 20 hari pemeliharaan. Perlakuan injeksi ekstrak daun karamunting mengalami peningkatan jumlah sel sperma relatif dibandingkan kontrol. Abnormalitas sel sperma terendah diperoleh pada perlakuan DK7,5 hari ke-20 sebesar 2,04 ± 0,93%. Persentase melaninasi pada spermatofor induk udang vaname jantan terendah diperoleh pada perlakuan DK7,5 dan DK10,0 yaitu sebesar 27% dan 20%. Injeksi ekstrak daun karamunting yang dilakukan lima hari sekali berpengaruh terhadap kualitas sperma induk udang vaname jantan. Hasil terbaik diperoleh pada dosis 7,5 mg/kg bobot tubuh setelah empat kali injeksi., Male vaname shrimp broodstock with optimal sperm quality is needed to support the productivity of superior seed supply. One of the plants that has potential to improve sperm quality in shrimp is karamunting (Melastoma malabathricum L.). This study aims to examine the effect of karamunting leaf extract injection on sperm quality of male vaname shrimp broodstock. Male vaname shrimp broodstock were treated by injecting distilled water as a control, as well as injections of karamunting leaf extract at following doses: 7,5 mg/kg body weight (DK7,5), 10 mg/kg body weight (DK10,0), and 12,5 mg/kg body weight (DK12,5). The extract was injected every five days for 20 days. Treatments injected with karamunting leaf extract increased the number of relative sperm counts compared to control. The lowest sperm cell abnormality was observed in DK7,5 treatment on day 20 at 2,04 ± 0,93%. The lowest percentage of melanized spermatophore was obtained in DK7,5 and DK10,0 treatments, at 27% and 20%, respectively. The injection of karamunting leaf extract which is done every five days affects the sperm quality of male vaname shrimp. The best results were obtained at a dose of 7,5 mg/kg body weight after four injections.
Keyword: udang vaname, karamunting, kualitas sperma

Judul: THE HEALTH STATUS OF SHRIMP (Litopenaeus vannamei) REARING WITHIN AND WITHOUT NURSERY METHODS
Abstrak: Udang vaname merupakan salah satu komoditas budidaya ekspor unggulan Indonesia. Rendahnya Survival Rate (SR) adalah salah satu kendala yang masih sering dijumpai sampai sekarang. Metode pendederan mengkondisikan udang supaya lebih sehat karena minim kontak langsung dengan suspensi limbah yang berada di dasar wadah budidaya, akumulasi limbah, dan pengadukan air lebih sedikit. Tujuan penelitian ini menganalisis dan membandingkan kinerja produksi dan status kesehatan udang vaname (Litopenaeus vannamei) pada pembesaran dengan metode pendederan dan tebar langsung. Penelitian ini dilakukan selama 84 hari. Penggunaan pendederan terbukti memiliki hasil produksi dan parameter respon imun yang lebih baik dengan rata-rata SR sebesar 92,70 % dan parameter respon imun yakni Aktivitas Fagositik (AF) dan Total Haemocyte Count (THC) yang lebih tinggi dan berbeda nyata yang secara berturut-turut nominalnya adalah 57,67 ± 2,51 % dan 11,53 x 106 ± 0,80 sel/ml. Nilai Respiratory Burst (RB) dan Phenoloxidase (PO) juga lebih tinggi meskipun tidak berbeda nyata. Selain itu, pada akhir penelitian, perlakuan pendederan mendapatkan hasil parameter kualitas air yang lebih baik, khususnya nitrit serta memiliki warna air yang lebih kehijauan. Penggunaan metode pendederan sebelum dilakukan penebaran dalam petak budidaya pada segmen pembesaran, dapat meningkatkan status kesehatan udang dan menekan kematian., Vaname shrimp is one of Indonesia's leading export cultivation commodities. Low Survival Rate (SR) is one of the obstacles that are still often encountered today. The nursery method conditions the shrimp to be healthier because there is minimal direct contact with the waste suspension at the bottom of the cultivation container, waste accumulation, and less water stirring. The purpose of this study was to observe, analyze, and compare the production performance and health status of vaname shrimp (Litopenaeus vannamei) on enlargement with nursery and direct stocking methods. The study was conducted for 84 days. The use of nursery proved to have better production results and immune response parameters with an average Survival Rate of 92.70 % and immune response parameters, like Fagositic Activity (FA) and Total Haemocyte Count (THC), which were higher and significantly different, respectively, the nominal was 57,67 ± 2,51 % and 11,53 x 106 ± 0,80 cells/ml. Value of Respiratory Burst (RB) and Phenoloxidase (PO) also higher but not significantly different. In addition, at the end of the research, the nursery method treatment obtained better water quality parameters, especially nitrites and had a greener water color. The use of nursery methode before stocking on enlargement rearing pond can improve health status and reduce mortality.
Keyword: Enlargement, health, imune, nursery, vannamei

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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