Pasteurella haemolytica infections in sheep

Area of Science:

• Veterinary Microbiology
• Animal Pathology

Background:

• Pasteurella haemolytica is a significant pathogen in sheep.
• This bacterium causes two primary disease syndromes with differing clinical presentations.

Purpose of the Study:

• To differentiate and describe the two disease syndromes caused by Pasteurella haemolytica biotypes A and T in sheep.
• To review current knowledge on the bacteriology, epidemiology, clinical findings, and immunology of these diseases.

Main Methods:

• Descriptive analysis of disease syndromes.
• Review of existing literature on bacteriology, epidemiology, clinical and necropsy findings.
• Assessment of experimental reproduction and immunology data.

Main Results:

• Biotype A of P. haemolytica causes septicaemia in lambs and pneumonia in sheep of all ages.
• Biotype T of P. haemolytica induces acute systemic disease, primarily affecting the upper alimentary tract and lungs in young sheep.

Conclusions:

• P. haemolytica presents distinct pathogenic profiles based on biotype.
• Understanding these differences is crucial for diagnosis, treatment, and control of sheep diseases.