Studies on immune response to Newcastle disease virus in broiler chickens fed with Lactobacillus reuteri PIA16 isolated from the gut of indigenous chicken of Assam, India.

BACKGROUND AND AIM: The chicken gut harbors microflora which impacts the health, production performance and immune response against pathogens. Assam local chickens reared under natural conditions are known to possess high immunocompetence which may be attributable to its gut microbiota make-up. This study aimed to investigate the individual effect of two strains of Lactobacillus reuteri PIA16 isolated separately from cecum and jejunum of Assam indigenous chicken on the immunity of broiler chickens against Newcastle disease virus (NDV) when fed singly and in combination with a prebiotic.

MATERIALS AND METHODS: A total of 240 birds (48 per group) were vaccinated with Lasota strain of NDV on the 5th and 21st day of age. Blood samples were collected before and after immunization against ND for the detection of humoral antibody response by hemagglutination inhibition test. The cell-mediated immune (CMI) response was estimated through response to phytohemagglutinin-P (PHA-P) and expressed as web index.

RESULTS: A significant influence on the immune response to NDV was observed in all the L. reuteri PIA16 as well as mannan oligosaccharide (MOS) supplemented groups revealing higher antibody titer than the control counterpart. The CMI response revealed a better cutaneous basophilic hypersensitivity response to PHA-P in the treated groups than the control.

CONCLUSION: Enhancement in immunity was perceived in the broilers fed with L. reuteri PIA16 and in combination with MOS due to the stimulation of the host's humoral and CMI response by the probiotics and prebiotics used.