Aktivitas kolinesterase dan laju konsumsi oksigen ikan nila merah (Oreochromis sp.) yang terdedah Curacron

ADHARINI, Ratih Ida, Drs. Suharno, SU

2006 | Tesis | S2 Biologi

Pencemaran insektisida dari limbah pertanian ke area budidaya ikan nila merah (Oreochromis sp.) mampu menurunkan produksi panen dan volume ekspor internasional. Penelitian ini bertujuan untuk mengetahui aktivitas kolinesterase, laju konsumsi oksigen, kadar hemoglobin dan hematokrit ikan nila merah yang terdedah insektisida organofosfat curacron. Hewan uji adalah ikan nila merah seleksi ukuran ±30 gram dari stasiun II unit kolam percobaan Jurusan Perikanan UGM. Penentuan LC 50-96 curacron menggunakan cara Tandjung (1982). Aktivitas kolinesterase plasma darah dan jaringan otak diperiksa menggunakan kolinesterase kit (DiaSys) secara spektrofotometri. Laju konsumsi oksigen (LKO2) diukur menggunakan respirometer modifikasi Johnson (1973). Kadar hemoglobin diperiksa dengan metode oksihemoglobin, hematokrit diukur dengan metode mikro-hematokrit. Penelitian menggunakan Rancangan Acak Lengkap, dianalisis statistik dengan Anova, uji LSD (Least Significant Difference) dan persamaan regresinya. Gejala kematian ikan dan kualitas fisikokimia air uji diperiksa setiap hari dan dianalisa secara deskriptif. Toksisitas curacron pada LC 50-96 sebesar 2,105 ppm. Semakin besar dosis menurunkan aktivitas kolinesterase secara nyata (P>0,05) pada plasma darah dan jaringan otak. LKO2 setelah 1 jam pendedahan mengalami peningkatan, namun setelah 24 jam hingga 96 jam mengalami penurunan (P>0,01; R2=0,9832). Semakin besar dosis selama 96 jam secara nyata meningkatkan kadar Hb (P>0,05; R2=0,9486) namun tidak beda nyata pada hematokrit (R2=0,6604). Curacron dapat menurunkan oksigen terlarut, dan pada konsentrasi tertentu berbahaya bagi organisme akuatik lainnya.

Insecticide from agricultural waste in aquaculture areas of red nila tilapia (Oreochromis sp.) may reduce harvest production and international export volume. This research aimed to study activity of cholinesterase, rate of oxygen consumption, hemoglobin level and hematocrit of red nila tilapia exposed to organophosphate insecticide of curacron. Tested animals were selected red nila tilapia with ± 30 g size from station II of experimental pond unit of UGM’s Fishery Department. Determination of curacron LC 50-96 used Tandjung (1982)’s way. Activity of cholinesterase of blood plasma and brain tissue was examined using spectrophotometer cholinesterase kit (DiaSys). Rate of oxygen consumption was measured using Johnson’s modified respirometer (1973). Hemoglobin level was measured with oxyhemoglobin, and hematocrit with micro-hematocrit methode. This research used complete random design. Data was analyzed statistically using ANOVA, LSD (Least Significant Difference) test and regression. Symp tomps of fish death and physicochemical quality of water was examined every day and analyzed descriptively. Toxicity of curacron in LC 50-96 was 2.105 ppm. The greater dosage reduced activity of cholinesterase significantly (P>0.05) in blood plasma and brain tissue. Rate of oxygen consumption increased after 1-hour exposure but after 24 to 96 hours decreased (P>0.01; R2=0.9832). The greater dosage for 96 hours increased Hb level significantly (P>0.05; R2=0.9486) but it was not significantly different in hematocrit (R2=0.6604). Curacron may reduced level of dissolved oxygen, and at certain concentration would be toxic for other aquatic organisms.

Kata Kunci : Insektisida Organofosfat Curacron,Pencemaran,Ikan Nila, cholinesterase activity, O2 consumption, organophosphate, hemoglobin, Oreochromis sp.