PERFORMA PEMBESARAN IKAN MAS RAJADANU (Cyprinus carpio) GENERASI KETIGA HASIL SELEKSI “WALKBACK”

Abstract

Timbulnya wabah penyakit KHV (Koi herpesvirus) pada budidaya ikan mas telah menurunkan produksi ikan mas nasional secara signifikan. Beberapa langkah dilakukan untuk mengatasi penyakit tersebut, salah satunya pembentukan ikan mas Rajadanu tahan KHV melalui seleksi. Dalam rangka memperoleh varietas unggul ikan mas tahan KHV pada tahun 2014 telah dilakukan pembentukan populasi F-3 melalui program selective breeding dengan metode walkback selection. Tujuan penelitian ini adalah menganalisis performa pertumbuhan ikan mas Rajadanu generasi ketiga hasil seleksi melalui uji skala lapang pada fase pembesaran, serta kegiatan uji tantang pada skala laboratorium. Benih F-3 merupakan hasil pemijahan F-1 betina dan F-2 jantan hasil seleksi positif MHC (Major Histocompatibility Complex), sedangkan kontrol berupa benih ikan mas Majalaya dari pembudidaya, masing-masing tiga ulangan. Uji tantang KHV dilakukan di akuarium berukuran 60 cm x 40 cm x 40 cm di hatchery ikan mas dengan suhu permissive 21°C melalui metode kohabitasi. Hasil penelitian menunjukkan bahwa populasi F-3 ikan mas Rajadanu hasil seleksi memiliki performa pertumbuhan relatif lebih baik 6,20% dibandingkan dengan kontrol pada karakter panjang total (18,14±4,90 cm), 5,80% lebih baik pada karakter panjang standar (14,76 ± 4,39 cm); 38,39% lebih baik pada karakter bobot rata-rata (393,98 ± 3,53 g); 16,83% pada karakter laju pertumbuhan spesifik (2,29 ± 0,04%); dan 3,80% pada karakter sintasan (49,13 ± 6,88%). Hasil uji tantang KHV menunjukkan sintasan populasi F-3 lebih tinggi (96,6 ± 3,3%) dibandingkan dengan kontrol (51,1 ± 8,3%).The outbreaks of KHV (Koi herpesvirus) disease in carp culture have significantly reduced Indonesia’s national carp production. Several strategies have been devised to combat the outbreaks including the development of KHV resistant carp varieties such as selective carp breeding program in 2014. The purpose of this study was to analyze the growth performance of the third generation (F-3) Rajadanu through field-scale test (grow out) and challenge test (laboratory-scale). The study was designed in a completely randomized design with two treatments (F-3 populations) and carp seed from the local small-scale fish farmers as control, each with three replicates. F-3 seed was produced from spawning between F-1 females and F-2 males which had a Major Histocompatibility Complex positive selection. The challenge test was carried out in the aquarium sized 60 cm x 40 cm x 40 cm at the hatchery with the permissive temperature of 21°C. The results showed that F-3 Rajadanu population had relatively higher total length (18.14 ± 4.90 cm) of 6.20%, standard length (14.76 ± 4.39 cm) of 5.80%, weight average (393.98 ± 3.53 g) of 38.39%, specific growth rate (2.29 ± 0.04%) of 16.83%, and survival rate (49.13 ± 6.88%) of 3.80% than that of control population. The result of the challenge test on KHV in the laboratory showed that F-3 population had higher survival rate (96.6 ± 3.3%) compared to that of control (51.1 ± 8.3%).