Analisis Kariogram Kromosom Ikan Neon Tetra (Paracheirodon innesi 1936, Myers) dari Famili Characidae

Abstract

Studies on the chromosomes of Neon Tetra fish (Paracheirodon innesi) are still limited. This study was conducted to obtain the chromosome karyogram, number, shape, and size of Neon Tetra fish. Fish samples were obtained from ornamental fish distributors in Medan and analyzed using a descriptive method. The samples were acclimated for four days in the laboratory and then immersed in 0.005% colchicine solution for 7–8 hours. Tissue preparation and slide making were performed using the solid tissue technique with gill organs, followed by staining with 2.5% Giemsa. Microscope slide observations were carried out using AmScope, and karyogram data analysis was performed using IdeoKar 1.3 software and Adobe Photoshop CS6. This study found that the diploid chromosome number of Neon Tetra fish was 22 pairs (2n=44), consisting of 19 metacentric chromosomes, 2 submetacentric chromosomes, and 1 telocentric chromosome. The largest chromosome measured 5.7 µm; while the smallest chromosome measured 2,6 µm; with an arm ratio value of 1,764; a relative length percentage of 5,592 and the highest chromosome type percentage 2,850; the r-value was 0,937 and the centromeric index was 0,478. Asymmetry index value included HCL at 912 µm, TF 42,76%; Ask 57,23%; and Xci 0,42%.