Biofilm vaccine of Aeromonas hydrophila– standardization of dose and duration for oral vaccination of carps

Humoral and protective responses to different doses and duration of oral administration of anAeromonas hydrophila biofilm vaccine in three species of carp, catla (Catla catla Ham.), rohu (Labeo rohita Ham.) and common carp (Cyprinus carpio Lin.) were studied. Among the three doses (107, 1010and 1013 cfu g−1fish d−1administered for 15 days, 1013 cfu g−1fish d−1, elicited the highest serum antibody titre and protective response in all the three carp species. Of the three vaccination durations studied (10, 15 and 20 d at 1010 cfu g−1fish d−1), 15 and 20 d induced higher responses than 10 d. Among the three carp species, catla produced the highest antibody and protective response followed by rohu and common carp. Independent of dose and duration, the antibody titre and protective response increased with time following vaccination up to 60 d.