Enhancement of immune responses to Newcastle disease vaccine by a supplement of extract of Momordica cochinchinensis (Lour.) Spreng. seeds.

Abstract

The study evaluated the immunological effect of extract of Momordica cochinchinensis (Lour.) Spreng. seeds (ECMS) on the immune response against Newcastle disease (ND) in chickens. Forty-eight chickens were divided into 4 groups (n = 12). Each chicken was immunized with ND vaccine mixed with 0, 20, 40, or 80 microg of ECMS on d 35. Blood samples were collected on d 0, 7, 14, 21, 28, and 35 postimmunization. Humoral and cellular immune responses were evaluated by indirect ELISA assay and the 3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyl tetrazolium bromide method. Results indicated that humoral immune response was enhanced by ECMS 14 d postimmunization. Eighty micrograms of ECMS was the best dose with the ND vaccine and was significantly different from the other groups 21 d after immunization. No significant differences were found in the cellular immune response, whereas the 80 microg of ECMS group had higher values than the other groups 35 d after immunization. No side effect was found on the growth performance during the experiment.