Study of reproduction and survival of guppies (Poecilia reticulata) brood stocks fed a compound food containing Spirulina sp.

The country's ornamental fish farming industry has been growing progressively and live spawning guppy is one of the top-selling ornamental fish in Iran and the world. Spirulina algae is rich in nutrients such as protein, amino acids, essential fatty acids and natural pigments and has many uses as a supplement for livestock, poultry and aquatic animals, especially ornamental fish. This research was conducted with the aim of comparing the effect of diets spirulina algae-supplemented and concentrate diets without spirulina algae on the reproductive and survival indices of guppy broodstock for 90 days. The rearing environment included glass aquaria under controlled conditions with an exposure time of 12 hours light and 12 hours of dark and a water temperature of 28 ± 1 °C. The four test groups included Treatment 1 (concentrate feed), Treatment 2 (concentrate feed with 5% spirulina algae), Treatment 3 (concentrate feed with 10% spirulina algae) and Treatment 4 (concentrate feed with 15% spirulina algae). Each treatment consisted of three replicates and five female and three male breeding specimens of Big Air Dumbo guppies imported from Thailand were kept in each replicate. The results showed the highest rate of relative fecundity (39.3±1.62) and productive larvae (150.0±2.65) and the lowest survival rate in the diet containing 15% spirulina algae supplement. During the breeding season, a significant difference in the survival rate of fish was observed with different treatments (p<0.05), such that the highest and lowest survival rates in female breeders were 93.33 ± 6.67 and 33.67 ± 6.67, respectively male breeders were observed 33.33 ± 0.0% and 88.88 ± 11.11 in treatments one and four, respectively. As a result, spirulina algae can be used as a suitable supplementary food in an environmentally friendly way in the diet in order to achieve optimal reproduction and survival in guppy ornamental fish.