ABSTRAKMengingat peranan zooplankton dalam ekosistem perairan sangat penting, maka dilakukan penelitian dengan tujuan untuk menganalisis struktur komunitas zooplankton yang meliputi jenis, kelimpahan, dan indek ekologi, dan  kaitan  distribusi zooplankton dan kualitas perairan di Perairan Kabupaten Lombok Utara. Pengumpulan data dirancang dengan sistem informasi geografis (SIG) pada 23 stasiun pengamatan yang ditentukan dengan teknik acak sederhana.  Hasil penelitian menunjukkan bahwa jenis dan kelimpahan zooplankton yang ditemukan di Perairan Kabupaten Lombok Utara cukup bervariasi dengan jumlah genus  sebanyak 9 yang terbagi  dari  5 kelas.  Berdasarkan perhitungan indeks ekologi menunjukkan bahwa struktur  komunitas zooplankton dalam kategori perairan yang kurang stabil. Kelimpahan dan indeks ekologi zooplankton  dipengaruhi oleh kondisi lingkungan (fisik-kimia) perairan antara lain  kecerahan, pH dan oksigen terlarut. Kata kunci : zooplankton,  struktur komunitas, kualitas perairan, kelimpahanABSTRACTConsidering that the role of zooplankton in aquatic ecosystems is very  important, research is carried out with the aim of analyzing zooplankton community structure which includes the type, abundance, and ecological index, and the relation of zooplankton distribution and water quality in North Lombok Regency Waters. Data collection was designed with a geographical information system (GIS) on 23 observation stations that were determined by simple random techniques. he results of this study indicate that the type and abundance of zooplankton found in the waters of North Lombok Regency are quite varied with the number of genus as many as 9 which are divided into 5 classes. Based on the calculation of the ecological index shows that the zooplankton community structure is in the category of less stable waters. The abundance and ecological index of zooplankton is influenced by the environmental (physical-chemical) conditions of the waters including brightness, pH and dissolved oxygen. Keywords: zooplankton, community structure, water quality, abundance

Kendala yang sering dihadapi oleh para pembudidaya adalah masalah hama dan penyakit yang dapat menurunkan kualitas udang dan kegagalan produksi. Penyakit yang sering menyerang udang adalah penyakit bakterial seperti vibriosis. Penyakit bakterial biasanya ditangani menggunkan antibiotik. Pada penelitian ini antibiotik yang digunakan berasal dari ekstrak daun mangrove Rhizophora apiculata yang memiliki kandungan senyawa aktif sebagai antibakteri. Penggunaan ekstrak daun mangrove R. apiculata diharapkan mampu meningkatkan performa pertumbuhan udang vaname melalui peningkatan sistem imun. Penelitian ini bertujuan untuk mengetahui pengaruh ekstrak daun mangrove R. apiculata terhadap performa pertumbuhan udang vaname (Litopenaeus vannamei). Penelitian ini dilakukan selama 40 hari. Perlakuan yang diberikan yaitu penambahan ekstrak daun mangrove R. apiculata ke dalam pakan udang yaitu P1 kontrol tanpa penambahan ekstrak, P2 diberikan ekstrak mangrove 0,5%, P3 diberikan ekstrak mangrove 1% dan P4 diberikan ekstrak mangrove 2%. Hasil yang diperoleh untuk performa pertumbuhan udang vaname perlakuan terbaik pada P4 (pakan + ekstrak mangrove 2%) dengan hasil pertumbuhan bobot mutlak sebesar 17,41 g, pertumbuhan spesifik sebesar 21,37%, kelangsungan hidup sebesar 93% dan konversi pakan sebesar 1,1. Daun mangrove R. apiculata dapat meningkatkan performa pertumbuhan udang vaname melalui pertumbuhan bobot mutlak, laju pertumbuhan spesifik, kelangsungan hidup dan nilai rasio konversi pakan, nilai terbaik diperoleh pada dosis ekstrak 2%  dengan masing-masing nilai 17,31  g, 21,37%, 93% dan 1,1%.

This study aims to determine tilapia's growth and immune system (Oreochromis niloticus) through feeding with added turmeric flour. This study used a completely randomized design with five treatments, namely K- (feed without adding turmeric flour and injected with physiological solution), K+ (feed without adding turmeric flour and injected with A. hydrophila bacteria), P1 (addition of turmeric flour 1 % / kg of feed + bacterial infection of A. hydrophilla), P2 (Addition of 2% turmeric flour/kg of feed + bacterial infection of A. hydrophilla), and P3 (Addition of 3% turmeric flour/kg of feed + bacterial infection of A. hydrophilla) each treatment had three replicates for a total of 15 trials. The results showed that there was a significant effect (p > 0.05) on growth but no significant effect (p < 0.05) on the survival of tilapia, so further tests were carried out to determine the best treatment in producing tilapia growth, it is known that P2 (Addition of 2% turmeric flour/kg of feed + bacterial infection of A. hydrophilla) is the best treatment in this study.

Chaetoceros sp. is a natural food that is widely used in fish and shrimp hatchery units because it has a fairly high protein content. One of the problems that often occurs lately is the difficulty of producing Chaetoceros sp. in large quantities due to production instability caused by the quality and quantity of Chaetoceros sp. which is not the same for each culture period. This study aims to determine the best color of light on the growth rate of Chaetoceros sp. The study was conducted with four white light, green, red, blue and yellow light treatments, each of which was repeated three times. The results showed that white light treatment produced the highest population density of 9,17 × cells / ml. then the yellow light treatment is 8,5 × cells / ml, then the blue light treatment is 5,33 × cells / ml, the red light treatment is 5 × cell / ml, and finally the light treatment of green is 4,67 × cells / ml. Based on the results of this study, it is recommended for the cultivation of Chaetoceros sp. to increase the optimum growth rate is white light.

Vannamei is an introduced shrimp that has economic value in both local and international market. One of the diseases that often attack vannamei shrimp is Vibrio parahaemolyticus. This study aims to determine the probiotic bacteria Lactobacillus sp. against vannamei shrimp immune response infected with V. parahaemolyticus, Survival rate, and bacterial V. parahaemolyticus density of the shrimp intestine. Shrimp used are shrimp that is 62 days which is kept in aquarium size 30x30x25 cm as many as 10 shrimp. The study was conducted with 5 controls: Control (-) (without Lactobacillus sp. and not infected), Control (+) (without Lactobacillus sp. and infected), P1 (Lactobacillus sp. 10 6 CFU / ml), P2 (Lactobacillus sp. 10 8 CFU / ml), P3 (Lactobacillus sp. 10 10 CFU / ml). The results showed that the administration of Lactobacillus sp. with a dose of 10 8 CFU / ml was able to increase THC vannamei shrimp by 5.58 x 10 6 cells / ml, hyaline cells and granular cells required in the shrimp immune system, increasing shrimp SR value by 86.67% and core growth of V. parahaemolyticus. Based on the results of this study is the use of probiotic Lactobacillus sp. which is recommended in the cultivation of vaname shrimp to improve the immune system, the level of shrimp survival and suppress the growth of bacteria V. parahaemolyticus is 10 8 CFU / ml.