Performa Pertumbuhan dan Daya Tahan Ikan Nila Oreochromis niloticus F1 Hasil Seleksi Berbasis Marka MHC I terhadap Penyakit Streptococcosis

Abstract

Streptococcosis, caused by the bacteria Streptococcus agalactiae, is a type of diseases that is often found in Nile tilapia farming. MHC I molecules are involved in immune system of vertebrate. This study was performed to evaluate the inheritance of the MHC I marker, the growth response and disease resistance of the first generation of Nile tilapia selected using marker assisted selection method and infected by S. agalactiae bacteria. First generation (F1) were produced by performing crossbreeds, namely: female and male having MHC I, female without MHC I x male having MHC I, female having MHC I x male having MHC I, and female and male without MHC I. MHC I marker inheritance in the progenies were identified, and challenged test was conducted by interperitoneally injecting of 0.1 mL S. agalactiae (107 CFU/mL) for 14 days. The inheritance of MHC I marker in F1 fish was relatively high level, ranging from 78.3-93.0%. Crossbreed of female and male without MHC I has 85.0% survival, highest than other treatments.