STUDI KASUS INFEKSI TILAPIA LAKE VIRUS (TiLV) PADA IKAN NILA (Oreochromis niloticus)

Abstract

Ikan nila atau Oreochromis niloticus merupakan ikan konsumsi masyarakat di Indonesia. Kasus kematian massal ikan nila terjadi di beberapa lokasi budaya di Jawa, Lombok, dan Sumatera yang disebabkan oleh infeksi Orthomyxovirus, dan disebut sebagai Tilapia Lake Virus (TiLV). Tujuan penelitian ini adalah untuk mendeteksi adanya infeksi TiLV dengan metode semi-nested Reverse Transcriptase-Polymerase Chain Reaction (RT-PCR) pada kasus kematian massal ikan nila. Lokasi pengambilan sampel di Desa Sigerongan Kecamatan Lingsar, Lombok, Nusa Tenggara Barat. Analisis deteksi RT-PCR menggunakan sampel organ otak, ginjal, limpa, dan hati, selanjutnya dilakukan sekuensing. Hasil pengamatan terhadap gejala klinis terhadap ikan nila moribund terlihat kondisi mata yang buram/katarak, serta cekung, abrasi kulit, serta perubahan warna tubuh menjadi lebih gelap. Hasil analisis RT-PCR menunjukkan bahwa kejadian kematian massal pada ikan nila suspektif diakibatkan oleh infeksi RNA virus TiLV. Analisis sekuensing menunjukkan bahwa TiLV dari sampel ikan nila di Lombok mempunyai kesamaan identitas genetik 97% dengan TiLV asal Israel (Genebank Accession Number KU 751816.1).

Oreochromis niloticus is the main consumption fish commodity in Indonesia. The mortality cases of Nile tilapia have occurred in several culture sites in Java, Lombok, and Sumatra due to the infection of Orthomyxovirus, Tilapia Lake Virus (TiLV). The purpose of this study was to detect the presence of TiLV infection in mass mortality case of Nile tilapia culture using the semi-nested Reverse Transcriptase-Polymerase Chain Reaction (RT-PCR). Fish samples were sourced from Segerongan Village Lingsar District, Lombok, West Nusa Tenggara. For RT-PCR analysis, samples from fish brain, kidney, spleen, and liver were collected and treated for sequencing analysis. The visual observation on the moribund tilapia had found several specific clinical symptoms such as eye cataract with sunken eyes, skin abrasion, and darkened body coloration. The result of RT-PCR analysis showed that mass mortalities of tilapia fish had been suspective caused by the infection TiLV RNA virus. The sequencing analysis showed that TiLV samples from Lombok have a genetic similarity of 97% with TiLV from Israeli (Genebank Accession Number KU 751816.1).