Immune response in rams experimentally infected with Brucella ovis

Area of Science:

• Veterinary Immunology
• Bacteriology

Background:

• Brucella ovis causes significant reproductive losses in rams.
• Understanding the immune response to B. ovis is crucial for developing effective control strategies.

Purpose of the Study:

• To characterize the cellular and humoral immune responses in rams experimentally infected with Brucella ovis.
• To investigate the potential role of cell-mediated immunity in protection against B. ovis.

Main Methods:

• Experimental infection of rams with Brucella ovis.
• Detection of specific antibodies using enzyme-linked immunosorbent assay (ELISA).
• Assessment of lymphocyte blastogenic responses to B. ovis antigen, phytohaemagglutinin, and concanavalin A.
• Evaluation of delayed-type skin hypersensitivity.

Main Results:

• Specific antibodies (IgM and total) were detectable by day 11 and peaked by days 33-41 post-infection.
• Antigen-induced lymphocyte blastogenesis was observed early (day 5) but decreased by day 63.
• Delayed-type skin hypersensitivity developed by day 63 post-infection.
• One ram with pre-existing cell-mediated immunity showed resistance to infection.

Conclusions:

• Both humoral and cellular immune responses are mounted against Brucella ovis infection in rams.
• Early development of cell-mediated immunity might be important for protection against B. ovis.