This is a very interesting study that explores the dynamics of genetic diversity in cultured aquarium Livebearer species.

ABSTRACT

Population study focusing on the genetic diversity had been widely exploited for wild species but unfortunately little attempt was being made to understand the dynamics of genetic diversity on cultured aquarium species. This study was carried out to understand the dynamics of genetic diversity of cultured livebearer fish in Malaysia.

Taxonomic groupings of both Xiphophorus and Poecilia spp was validated using molecular markers. 130 samples of locally cultured livebearer fishes which comprised of Xiphophorus maculatus, Xiphophorus helleri, Poecilia reticulata and Poecilia latipinna were sampled.

The livebearer fish samples were genotyped with 24 microsatellite (SSRs) primer pairs. Fifteen out of 24 SSRs primer pairs were able to amplify among the livebearer fishes and were polymorphic. The average number of alleles was low (1 to 8). Differences between mean observed (Ho) and expected (He) heterozygosity for the four species of livebearer fishes were small ranging from 0.02 to 0.06 suggesting no drastic reduction of heterozygosity in cultured fish. The pair-wise comparisons of Fst between these four species of livebearers in general was high (Fst>0.25).  Such observation was expected as the four tested species of livebearer belong to different taxonomic groups. A clear distinction between the species of Xiphophorus and Poecilia as revealed by SAHN-clustering tree plot seems to be in accordance with their taxonomy.

The data generated from this study provides useful information in understanding the genetic variation in cultured aquarium fish for resource management and conservation.

Genetic Relationships Between Poecilia latipinna & Selected Livebearer Fishes in Malaysia