Isolasi dan Identifikasi Bakteri Patogen Serta Deteksi ISKNV Pada Pembesaran Ikan Nila (Oreochromis niloticus)

Abstract

Kegiatan akuakultur berkontribusi dalam memenuhi kebutuhan protein hewani di dunia. Salah satu komoditas akuakultur yang menunjukkan peningkatan jumlah produksi setiap tahun yaitu ikan nila (Oreochromis niloticus). Namun, ditemukan koinfeksi antara bakteri patogen Aeromonas hydrophila (AH) dan Infectious Spleen and Kidney Necrosis Virus (ISKNV) pada benih ikan nila yang menyebabkan kematian tinggi. Penelitian ini bertujuan untuk mengisolasi dan mengidentifikasi bakteri patogen, serta mendeteksi ISKNV pada pembesaran ikan nila. Penelitian ini dilakukan dengan beberapa tahap, diantaranya isolasi dan identifikasi bakteri dari sampel air pemeliharaan dan ikan sakit, deteksi ISKNV pada ikan yang sakit, uji patogenisitas bakteri melalui uji hemolitik eritrosit dan uji Postulat Koch. Parameter penelitian ini yaitu pengelompokan bakteri hasil isolasi, persentase prevalensi isolat bakteri patogen, tingkat kelangsungan hidup ikan, dan analisis kualitas air yang terdiri atas DO, pH, suhu, dan amonia. Hasil penelitian ini menunjukkan terdapat lima isolat bakteri patogen diantaranya isolat 27O-2 Aeromonas hydrophila O, 27I-1 Aeromonas hydrophila I, NM12 Enterobacter cloacae, NW12 Acinetobacter schindleri, dan NW13 Stenotrophomonas maltophilia. Uji Postulat Koch menunjukkan bahwa persentase prevalensi isolat bakteri patogen berbeda-beda yaitu isolat 27O-2 Aeromonas hydrophila O sebesar 80%, 27I-1 Aeromonas hydrophila I 70%, NM12 Enterobacter cloacae 30%, NW12 Acinetobacter schindleri 30%, dan NW13 Stenotrophomonas maltophilia 60%. Berdasarkan hasil deteksi ISKNV menunjukkan bahwa ikan sakit tidak disebabkan oleh koinfeksi antara bakteri patogen dan ISKNV.

Aquaculture activities contribute to meeting the world's need for animal protein. One of the aquaculture commodities that shows an increase in production every year is tilapia (Oreochromis niloticus). However, co-infection between pathogenic bacteria Aeromonas hydrophila (AH) and Infectious Spleen and Kidney Necrosis Virus (ISKNV) was found in tilapia seeds which caused high mortality. This study aims to isolate and identify pathogenic bacteria, as well as detect ISKNV in tilapia fish farming. This study was conducted in several stages, including isolation and identification of bacteria from maintenance water samples and sick fish, detection of ISKNV in sick fish, bacterial pathogenicity test through erythrocyte hemolytic test and Koch's Postulate test. The parameters of this study were grouping of isolated bacteria, percentage prevalence of pathogenic bacterial isolates, fish survival rate, and water quality analysis consisting of DO, pH, temperature, and ammonia. The results of this study showed that there were five isolates of pathogenic bacteria including isolates 27O-2 Aeromonas hydrophila O, 27I-1 Aeromonas hydrophila I, NM12 Enterobacter cloacae, NW12 Acinetobacter schindleri, and NW13 Stenotrophomonas maltophilia. The Koch Postulate test showed that the percentage of prevalence of pathogenic bacterial isolates varied, namely isolate 27O-2 Aeromonas hydrophila O was 80%, 27I-1 Aeromonas hydrophila I 70%, NM12 Enterobacter cloacae 30%, NW12 Acinetobacter schindleri 30%, and NW13 Stenotrophomonas maltophilia 60%. Based on the results of ISKNV detection, it was shown that sick fish were not caused by coinfection between pathogenic bacteria and ISKNV.