CLINICOPATHOLOGICAL AND IMMUNOLOGICAL EFFECTS OF USING FORMALIZED KILLED VACCINE ALONE OR IN COMBINATION WITH PROPOLIS AGAINST Pasteurella multocida CHALLENGE IN RABBITS

Abstract

Pasteurellosis is a common and troublesome issue of rabbits causing serious disorders. The immunization procedures are constantly the greatest preventive measures. In the present study, 40 New Zealand rabbits were used to investigate the protective efficacy of formalized Pasteurella multocida vaccine alone or in combination with propolis. The animals were divided into four equal groups (I-IV); negative control group, challenged non-vaccinated group, vaccinated challenged group and vaccinated propolis administered challenged group respectively. At the end of the 2nd and 6th weeks of the experiment, blood samples were collected from ear vein of rabbits for hematological, plasma, and serum examinations. The rabbits were then anaesthetized and sacrificed to collect tissue specimens from liver, kidneys, spleen and lungs for histopathological study. The results showed that using of propolis in combination with killed vaccine of Pasteurella multocida improved the immune response by increasing the leukocyte phagocytic activity against Pasteurella multocida (from 23.80% to 60.80%). Moreover, the clinicopathological findings including hemogram (RBCs count, Hb content, PCV, RBCs indices, platelets, total and differential leukocytes count), and hepato-renal function tests (ALT, AST, ALP, bilirubin, urea and creatinine), as well as, histopathological findings were better in infected rabbits treated with propolis- killed vaccine than using killed vaccine alone.