The impact of apple cider vinegar on nonalcoholic fatty liver disease in rainbow trout, Oncorhynchus mykiss: A study of therapeutic potential and health benefits

In this study, we aimed to experimentally induce fatty liver disease in rainbow trout, Oncorhynchus mykiss, and then assessed the illness recovery process, growth, and changes in the expression of FAAH and ACADL genes in both healthy (0 [C2] and 4% apple cider vinegar [T4]) and diseased fish (0 [C1], 1 [T1], 2 [T2], and 4% [T3]) apple cider vinegar. To conduct the study, 180 rainbow trout were randomly assigned to six different experimental treatments, each with three replications. The investigation lasted for 60 days. Growth indices, liver histology, blood biochemical parameters, and transcription of the ACADL and FAAH genes in the liver tissue were measured. The study found no significant differences in the final weights across all the treatments. Apple cider vinegar (ACV) administration resulted in a decrease in AST, ALT, and ALP; however, these values did not show a significant difference from C2. In T3, triglycerides significantly decreased (p < 0.05), whereas in T4, triglycerides significantly increased (p < 0.05). Hepatocytes from ACV-containing treatments showed reduced fat compared with T4 and the control group (C1). While there was a significant difference (p < 0.05) in the expression of the FAAH gene, there was no significant difference (p > 0.05) in the expression of the ACADL gene between experimental treatments. The findings of our study indicate that an inclusion of up to 2% ACV may have positive effects on trout aquaculture and NAFLD treatment.