Study on the total proteins and main protein fractions in rabbits experimentally infected with Staphylococcus aureus

Abstract

Infections with Staphylococcus aureus are a common cause which can induce severe skin infections in rabbits leading to important economic losses. The present study was conducted to evaluate the changes in the concentrations of total protein, albumin, globulin, fibrinogen, and albumin/globulin ratio during S. aureus infection using a model for experimental infection of rabbits. The experiment was carried out on 13 rabbits at the age of 3 months. Infection was induced by inoculation of 7 rabbits by100 μL of bacterial suspension of a field S. aureus strain (density: 8х108 cfu/mL) and 6 other rabbits were not treated (controls). Blood samples for principal protein analysis were collected before (0 h) and at 24, 48 and72 h on day 7, 14, and 21 after infection. Total protein level showed little changes in the experimental group. The concentration of albumin decreased in the experimental group since 32.2±2.30 g/L to 27.3±1.9g/L. The serum level of globulins rose significantly (P<0.05) in the experimental group and slightly in the control group. Albumin/globulin ratio was lowered and significantly different on day 4 (P<0.01) and on day 7 (P<0.001). The concentration of fibrinogen was used as an acute phase protein with aim to confirm the incidence of infection. In parallel, rectal temperature and skin lesions (abscesses) were recorded. In all infected animals, formation of abscess due to the proliferation of the inoculated strain was observed within 48-96 h following the bacterial inoculation and these lesions have gradually extended leading to purulent exudates several days after and sometimes to secondary abscesses in surrounding muscles.

Keywords

• Rabbits
• blood
• protein fractions
• infection
• Staphylococcus aureus