Influence of Probiotics and Spirulina on Growth Performance and the Expression of gh, igf 1, and igf 2 Genes in Nile Tilapia (Oreochromis niloticus) Under Sumithion Induced Toxicity

Abstract

Sumithion, a commonly used pesticide in aquaculture, poses potential toxicity risks to fish. This study aimed to evaluate the protective effects of probiotics and Spirulina against sumithion toxicity on growth performance including weight gain (WG), specific growth rate (SGR), and feed conversion ratio (FCR), along with the mRNA levels of growth hormone (gh) genes in the pituitary and insulin like growth factors (igf 1 and igf 2) genes in the liver were assessed in Nile tilapia (Oreochromis niloticus). Fish were assigned to four treatment groups: Control (no sumithion, probiotics, or spirulina), Sumithion exposed (0.3 mg/L), Sumithion + Probiotics (1.0 ml/L in water), and Sumithion + Spirulina (50 g/kg feed), with three replicates per group over a 42 day trial. Fish in the sumithion + probiotics group exhibited the highest WG (40.86 ± 7.38 g) and SGR (1.30 ± 0.22 %/day) while achieving the lowest FCR (0.94 ± 0.24). The intestine somatic index (ISI) was highest in the sumithion + probiotics group (2.58 ± 0.49), whereas the hepatosomatic index (HSI) was significantly increased in the sumithion + spirulina group (2.32 ± 0.28). Relative expression of gh mRNA in the pituitary was significantly upregulated in fish treated with sumithion + probiotics compared to the other groups. Similarly, a 3 fold and 1.92 fold expression of igf 1 and igf 2 respectively were found markedly higher in the sumithion + probiotics group compared to the control in the liver. These findings indicate that probiotics and spirulina can mitigate sumithion induced toxicity, enhance growth performance, and activate the GH/IGF axis highlighting the potential dietary supplements for improving fish health in aquaculture.