STRUKTUR HISTOLOGI INSANG IKAN MUJAIR (Oreochromis mossambicus L.) SEBAGAI INDIKATOR KUALITAS AIR LAGOON NUSA DUA, BALI

Abstract

Nusa Dua is a popular tourist resort in Bali, where many hotels and other tourist facilities were built. In this resort, the sewage is centralized processed in a Sewage Treatment Ponds called “Unit Pengolahan Air Limbah PT ITDC” which is also often called Lagoon Nusa Dua. Nusa Dua sewage treatment ponds have 5 units of ponds, namely Pond 1A, 1B, 2A, 2B, and Pond 3. In ponds 2B and 3, tilapia fish (Oreochromis mossambicus Linn.) was raised as a water quality bio-indicator. The aim of this research was to determine the histology condition of the gill of tilapia fish that raised in the Nusa Dua sewage tretment ponds which were then used as an indicator of water quality in these ponds. The research employed a complete randomized design in which 16 samples were taken from two sampling sites with eight replications. Results of this research showed that histologic changes of the gill that were observed including edemas, fusions, and hyperplasias of secondary lamellas as well as telangiectases. Keywords: Nusa Dua sewage, Oreochromis mossambicus L., gills, histology, bioindicator