Effects of Spirulina platensis and Cladophora sp. on immunity stimulating capacity and color improvement of goldfish (Carassius Auratus)

Abstract

The aim of this study were to determine the growth, immunity stimulating capacity, and color improvement of goldfish, Carassius auratus, when feeding with two types of algae. The experiments were divided into 4 treatments with 3 replications each: treatment 1 the goldfish was fed with commercial diet, while treatments 2 and 3 were with commercial diets supplemented with 6 and 12% of Spirulina platensis powder, and treatment 4 with commercial diets supplemented with 6% of Cladophora sp. powder. Goldfish with the initial average weight of 13.9 ± 0.73 g were fed with these diets for 60 days. It was found that growth performance of fish in all treatment were not significantly different. The average haematocrit of fish in treatment 2 was highest (44.0 ± 0.6 percent). The average phagocytosis activity of fish in treatment 3 was highest (62.7 ± 1.4 percent). According to their coloration, the average brightness of the treatment 2 was least (47.4 ± 1.4). The average red color was highest in treatment 3 (33.7 ± 1.8), and the average yellow in treatment 4 (49.9 ± 0.9). In conclusion, both Spirulina platensis and Cladophora sp. supplementary diets had no effect on the fish growth rate but they can stimulate the immune system and improve the red and yellow color in goldfish.