Oregano (Origanum vulgare) Extract Enhances Zebrafish (Danio rerio) Growth Performance, Serum and Mucus Innate Immune Responses and Resistance against Aeromonas hydrophila Challenge

Abstract

This study evaluated the dietary effects of an ultrasound-assisted extract of Origanum vulgare on the growth, antioxidant and immune responses (serum and mucosal) and resistance of zebrafish (Danio rerio) against Aeromonas hydrophila. Four hundred and forty adult zebrafish were distributed into 12 tanks and fed 4 experimental diets including 0% (control), 0.5% (M1), 1% (M2) and 2% (M3) of the extract per kg−1 diet for eight weeks. Fish were then challenged with A. hydrophila and mortality was recorded for 10 days. Results revealed that the extract exerted potent effects on growth parameters of weight gain and specific growth rate. The feed conversion ratio was significantly lower in fish fed extract-incorporated diets. O. vulgare extract improved antioxidant and immune responses, resulting in less sensitivity to oxidative stress and a higher survival rate when challenged with A. hydrophila. Overall, the greatest effects were observed in individuals with 1% dietary inclusion of the extract. These results suggest that the extract from the plant Origanum vulgare possesses a great potential to be used in the aquaculture industry and that zebrafish is an appropriate model for nutrition studies.

Zebrafish as a Screening Model to Study the Single and Joint Effects of Antibiotics

“…The limitations of traditional mammalian models motivated the researchers to search for alternative vertebrate model systems. In this context, the use of zebrafish ( Danio rerio ) to study the toxic effects of molecules or therapeutic efficacy has grown markedly in recent decades [ 6 , 7 , 8 , 9 , 10 , 11 ]. Their rapid life cycle, small size, external development, prolific spawning and genetic and physiological similarities with mammals are some of the main attractions of zebrafish as an alternative to traditional organism models for toxicology studies.…”

Phytogenic Bioactive Compounds Shape Fish Mucosal Immunity

“…The repeatedly evaluated markers were lysozyme, alkaline phosphatase, complement and protease activities, total immunoglobulin and protein content in fish skin mucus, as well as its in vitro bactericidal potential against bacterial pathogens. Several of these studies also described an improvement in key performance indicators, such growth, feed efficiency and survival against pathogenic bacterial challenges (56,58,65,71,(73)(74)(75)(76)(77)(78)(79). Besides the assessment of key performance indicators and general immune markers in skin mucus, few studies have tried to explain and characterize the immunomodulatory mechanisms underlying such responses neither which specific compounds might be exerting such effects.…”

Spices and herbs as immune enhancers and anti-inflammatory agents: a review

“…The bioactive compounds present in African potato are terpenoids, saponins, tannin, reducing sugars, phytoglycosides, and sterols Increased lysozyme, protease, and bactericidal activity Fish Zhang et al, 2020;Beltrán et al, 2020;Espirito Espirito Santo et al, 2018;Mabrok and Wahdan, 2018;Shourbela et al, 2021;Rashidian et al, 2021 Increased specific Ig Broiler chicken Galal et al, 2016;Franciosini et al, 2016 -Moreno et al, 2017;Wang-sheng et al, 2017;Ren and Liang, 2018;Pei et al, 2020;Mao et al, 2017;Viswanadha et al, 2020 Inhibited macrophage inflammation in pancreatic islets Mouse Yuan et al, 2021 Treated allergic inflammatory through major T helper cell groups Mouse Bui et al, 2017;Bui et al, 2019 Chili powders (Capsicum species)…”

“…Moreover, Nile tilapia supplemented with oregano essential oil at 1 or 2 mL/kg of diet had increased lysosomal and phagocytic activities as well as rendering improvements in erythrocytes and leukocytes levels (Shourbela et al, 2021). Oregano extract supplementation of zebrafish (Danio rerio) resulted in increased lysozyme and protease activity (Rashidian et al, 2021). However, increases were most significant with fish supplemented 1% extract per kg of diet, with less significant increases with 0.5 and 2% supplementation (Rashidian et al, 2021).…”

“…Oregano extract supplementation of zebrafish (Danio rerio) resulted in increased lysozyme and protease activity (Rashidian et al, 2021). However, increases were most significant with fish supplemented 1% extract per kg of diet, with less significant increases with 0.5 and 2% supplementation (Rashidian et al, 2021).…”