Asian Journal of Fisheries and Aquatic Research

This research aims to determine the optimum potassium diformate (KDF) dosage which was added to feed to increase the immune status of goldfish (Carassius auratus L). This study was conducted from September 31 - November 15, 2019 at the Laboratory of Aquaculture and Molecular Biotechnology Laboratory of the Faculty of Fisheries and Marine Sciences, University of Padjadjaran. The research method used is the experimental Complete Random Design (CRD) with 4 treatments and 3 replications. The treatments are A (without KDF/control), B (0.1% KDF), C (0.3% KDF) and D (0.5% KDF). The observed parameters are survival rate, total leukocyte count (white blood cells), total erythrocyte count (red blood cells) and gross clinical sign. Observations were made after 30 days of KDF and post-test challenge by Aeromonas hydrophila for 14 days. Data on the number of total leukocyte count and total erythrocyte count were analyzed using F test and Duncan's advanced test at a 95% confidence level, while the gross clinical sign data were analyzed descriptively. The results showed that the KDF 0.3% was the optimum dose and was very effective in optimizing the performance of the goldfish immune system optimally, seen from the number of white blood cells and red blood cells which experienced the highest increase of 23.48% and 9.30%. After the challenge test, fish that were given KDF 0.3% had the highest survival rate of 46.67%. In addition, the process of recovering the number of white blood cells and red blood cells can be faster than other treatments, with a value of 12.85×10⁴ cells mm^3-1 and 0.96×10⁶ cells mm^3-1, marked also by the healing of clinical symptoms in the morphology of goldfish.