Analisis Kariotipe Kromosom Ikan Hias Ekor Pedang (Xiphophorus hellerii Heckel, 1848)

Abstract

The genetic aspect of the swordtail fish (Xiphophorus hellerii), a member of the Poeciliidae family, rarely to known. The fish has a very high market value and can be produced as an attractive fish farming product. Therefore the study of Karyotipe of the swordtailfish had been conducted by using description method.10 pairs of fish samples were gathered from vendors of ornamental fish in the city of Medan. Samples were brought to the lab and acclimated for 7 days. Colchicine was administered using a concentration of 0,007% and soaking time of 12 hours. The tissue preparation was carried out by the solid tissue technique, and stained by using Giemsa staining 5%. The number, size, and shape of the chromosomes were the three variables that were evaluated. IdeoKar ver. 1.3 software and Adobe Photoshop CS3 were used to collect the data. The outcomesof the research demonstrated that the swordtail fish contained 24 pairs of diploid chromosomes (2n=48), the most of which were metacentric chromosomal types. The biggest figure for the swordtail chromosome's size was found on chromosome 1, which had a total arm size (CL) of 8,33 µ. The highest chromosome r-value was 0,97µ, the longest chromosome relative length (RL%) was 7,18 µ, the greatest chromosomal shape percentage (F%) was 39,601 µ, the largest chromosome arm ratio (AR) was 1,08 µ, and the largest index value was centromere (CI) 0,49 µ. A low average centromere index (XCI) was 0,385µ and a large total haploid complement length (HCL) was 115,900 µ characterize the chromosomal makeup of swordtail fish, respectively