Immunological and pathological effects of vitamin E with Fetomune Plus® on chickens experimentally infected with avian influenza virus H9N2

• Published in: Veterinary microbiology 2019-04, Vol.231, p.24-32
• Main Authors: Awadin, Walaa F., Eladl, Abdelfattah H., El-Shafei, Reham A., El-Adl, Mohamed A., Ali, Hanaa S.
• Format: Article
• Language: English
• Subjects: AIV H9N2; Autopsy; Avian flu; Birds; Chickens; Chicks; Dietary supplements; Drinking water; Duodenum; Farms; Fetomune Plus; Gene expression; Hemagglutination inhibition; Histopathology; Immunohistochemistry; Immunology; Immunostimulants; Infections; Influenza; Interferon; Interleukin 2; Interleukin 6; Juveniles; Lesions; Organs; Pathological effects; Poultry; Poultry farming; Spleen; Viruses; Vitamin E; Vitamins; γ-Interferon
• ISSN: 0378-1135; 1873-2542
• DOI: 10.1016/j.vetmic.2019.02.028

•Effects of Vitamin E with Fetomune Plus® infected chickens with AIV H9N2 were performed.•Low virus shedding titers and improved gene expressions and HI titers were recorded in the treated group.•The supplements for four weeks had protective role, improved body weight and low mortalities.•Mild lesions in examined organs by histopathological examination were detected in the treated group.•Lower staining intensity of H9N2 antigen examined organs by IHC was observed in the treated group. Avian influenza virus (AIV) H9N2 infection causes economic losses on poultry farms, and immunostimulants are essential for improving chicken immunity. This study evaluated the immunological and pathological effects of vitamin E with Fetomune Plus® (a commercial product based on a yeast extract and vitamins) on chickens experimentally infected with AIV H9N2. Three groups of white Hy-Line chicks were included. The G1 group was kept as an uninfected untreated control, the G2 group was intranasally infected with the AIV H9N2 strain (0.5 ml of 106 50% egg infectious dose (EID50)), and the G3 group was infected and treated with vitamin E (200 mg/kg of diet) and Fetomune Plus® (1 ml/liter of drinking water) for four weeks. The gene expression of interferon-gamma (IFN-γ), interleukin (IL)-6, and IL-2 was determined at 3, 5 and 7 days post-infection (PI). Virus shedding titers and rates and haemagglutination inhibition (HI) antibody titers were detected. Clinical signs, mortalities and post-mortem lesions were recorded. The birds were weighed, and relative organ weights were calculated. Tissue specimens were taken for histopathological examination and immunohistochemistry (IHC). The expression of IFN-γ in the duodenum revealed a significant increase in G2 compared to G3 at 3 days PI, while the duodenal and splenic expression of IL-6 was significantly increased in G2 compared to G3 at 5 days PI. IL-2 was overexpressed in the duodenum in G3 compared to G2 at 3 and 5 days PI. A significant decrease (P ≤ 0.05) in the virus shedding titer and an increase in the HI titers were detected in G3 compared to G2. The clinical signs and the mortality rate were clearly appeared in G2 than in G3. By IHC, lower H9N2 staining intensity was observed in the examined organs from G3 than in those from G2. In conclusion, as a first report, vitamin E with Fetomune Plus® supplementation for four weeks could improve the immunological and pathological effects of H9N2 infection on chickens.