Hemato-biochemical and histopathological effects of blue-green algae, probiotic, and antibiotic in Cyprinus carpio L

Feed additives in fish rations improve feed efficiency, increase the growth rate of fisheries, and play a significant role in the immunoprophylactic control of infections in aquaculture. This study aims to evaluate the hematological and biochemical effects of Spirulina, PoultryStar®, and colistin on Cyprinus carpio, as well as the histopathological alteration caused in the liver and intestine of C. carpio fed with these additives. One hundred and eighty C. carpio fish were grouped into six groups of thirty fish each for the purpose of the experiment. Group A was fed a diet without any additives, and this served as the control group. Groups B and C were fed diets that contained 1% and 2% of Spirulina, respectively. PoultryStar® at 1% and 2% was added to the diet fed to fish in groups D and E, respectively, while group F was fed a diet that contained 3000 IU of colistin. Blood samples were collected and subjected to hematological and biochemical assays for the evaluation of hemato-biochemical indices. Liver and intestine samples from each experimental group were subjected to histopathological analysis. There were significant differences (p < 0.05) in the hematological and biochemical indices of the different groups of fish. The histopathologic examination of the liver and intestine samples of C. carpio treated with Spirulina, PoultryStar®, and colistin revealed variable pathological alterations. Findings from this study showed that Spirulina and PoultryStar® could be used in aquaculture, and studies should be conducted to further determine the prospects of colistin in pisciculture.