Production and use of immunoglobulin Y in the diagnosis of haemorrhagic septicemia caused by Aeromonas hydrophila in Piaractus mesopotamicus

Aeromonas hydrophila is an opportunistic pathogen frequently isolated from outbreaks with higher mortality rates in tropical farms, causing disease in pacus Piaractus mesopotamicus. The objective of this study was to obtain a purified polyclonal immunoglobulin Y (IgY) by immunizing laying White Leghorn hens with A. hydrophila. Antibodies anti-A. hydrophila derived from the yolks and serum of hens showed antibody titres increased at 60 days and remained detectable until 90 days after immunization. Pacus were challenged intraperitoneally with A. hydrophila and the capacity of antibodies to detect A. hydrophila was tested by immunohistochemistry using tissues from pacus. The results observed in this study demonstrated the utility of IgY for the diagnosis of A. hydrophila within the phagosomes of phagocytes and extracellular bacteria colonizing host tissues in pacus.