Stimulatory effect of dietary chasteberry (Vitex agnus-castus) extract on immunity, some immune-related gene expression, and resistance against Aeromonas hydrophila infection in goldfish (Carassius auratus)

• Published in: Fish & shellfish immunology Vol. 107; no. Pt A; pp. 129 - 136
• Main Authors: Rashmeei, Maedeh, Hosseini Shekarabi, Seyed Pezhman, Shamsaie Mehrgan, Mehdi, Paknejad, Hamed
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.12.2020
• Subjects: Aeromonas hydrophila - physiology; Animal Feed - analysis; Animals; Diet - veterinary; Dietary Supplements - analysis; Disease Resistance - drug effects; Disease Resistance - genetics; Dose-Response Relationship, Drug; Fish Diseases - immunology; Gene Expression - immunology; Goldfish - immunology; Gram-Negative Bacterial Infections - immunology; Gram-Negative Bacterial Infections - veterinary; Humoral immunity; Immunity, Cellular - drug effects; Immunity, Innate - drug effects; Immunostimulant; Inflammatory cytokines; Plant Extracts - administration & dosage; Plant Extracts - metabolism; Random Allocation; Skin mucosal immunity; Vitex - chemistry; Immunostimulant; Skin mucosal immunity; Inflammatory cytokines; Humoral immunity
• ISSN: 1050-4648; 1095-9947
• DOI: 10.1016/j.fsi.2020.09.037

Chasteberry is highly recommended as an herbal medicine across the globe for treating of many gynaecological disorders. In this study, chasteberry extract (CBE) was supplemented in goldfish diet to evaluate the immunity responses at the cellular and molecular levels. Moreover, after the feeding trial, the fish were challenged with Aeromonas hydrophila. The fish (300 individuals, 2.4 ± 0.12 g initial weight) were randomly distributed in 12 tanks and were fed with 0 (control), 5, 10, and 15 g CBE per kg of feed for 8 weeks. Based on the results, lysozyme activity, alkaline phosphatase, and total immunoglobulin (Ig) in the skin mucus samples were significantly enhanced in the fish fed with 15 g/kg CBE (P < 0.05). Moreover, dietary CBE positively affected lysozyme activity, complement components, and IgM content of the serum samples compared to the control group. Also, the number of monocytes and lymphocytes were increased significantly with increasing CBE in the diet (P < 0.05). The highest mRNA levels of tumor necrosis factors (TNF-α, TNF-2α) and Lysozyme were observed in 15 g/kg CBE treatment. After the challenge test, the highest relative percentage survival value (60%) was observed in the fish fed with 15 g/kg CBE. We concluded that dietary CBE especially at 15 g/kg has an immunomodulatory effect in goldfish by stimulating the innate immunity and some inflammatory cytokines as well as disease resistance against A. hydrophila. •No previous study has investigated the effects of dietary chasteberry extract (CBE) on the immunity of goldfish.•Feeding the fish with 15 g/kg CBE was more effective than other doses to improve mucosal and serum immunological parameters.•The oral administration of CBE could act as a natural immunostimulant in goldfish diet.•Supplementation of the fish diet with CBE can upregulate some immune-related gene expression.