Modulatory effects of dietary jackfruit peel waste on haematology, immune, genes responses during ammonia toxicity in Nile tilapia

Abstract The current study examined how dietary supplementation with jackfruit peel waste (JPW) protects Nile tilapia ( Oreochromis niloticus ) fingerlings from waterborne NH 3 toxicity by regulating genes linked to inflammation, apoptosis, immunological activities, and tight junctions. After 56 days of feeding fish (22–23 g) on grade levels of JPW diets (0.0, 1.0, 5.0, and 10.0 g/kg diets), the fish were exposed to NH 3 (0.5 mg/L) for 3 h. The NH 3 exposure led to significant declines in all haematological indices, while the WBC, Hb, and Hct levels were progressively elevated in fish fed with increasing levels of JPW diets. Meanwhile JPW-fed fish groups displayed significant elevations in all immune parameters, whereas fish exposed to NH 3 without JPW exhibited significant declines in all immune parameters. Fish fed with 5.0 and 10.0 g JPW/kg diet found that all immune indices were affected by dietary JPW, NH 3 toxicity, and their interaction where their values were increased with increasing JPW levels but declined after NH 3 exposure. The expression of all immune-related genes was evidently higher in fish fed on dietary JPW and declined after NH 3 toxicity. IL-1β, IL-8, TNF-α, and IFN-γ genes expressions were affected by dietary JPW, NH 3 toxicity, and their interaction. The IL-10 gene expression among different levels of JPW diets was not greatly altered. The p53, Bax, Bcl, Caspase3 , and Caspase9 genes expression was significantly higher in NH 3 -exposed fish, whereas feeding the fish on different levels of JPW diets exhibited slight modification. The tight junction (TJ) proteins expression was upregulated in fish exposed to NH 3 toxicity, while slight regulation was noticed in fish fed on JPW diets. The current investigation depicted that dietary JPW enrichment, especially at 5.0 g JPW /kg feed has a beneficial role on health, enhances immune response and immune-related genes, and safeguards inflammatory, apoptosis, and TJ-related gene transcription in Nile tilapia during NH 3 toxicity.