Clinical examination of 380 rearing sheep revealed that 30 animal were suffering from skin abscesses with an incidence of (7.89%). Bacteriological examination of 30 swabs from affected sheep revealed isolation of 30 isolates of C. pseudotuberculosis (48.39%) , 18 isolates of S. aureus (29.03%) and 14 isolates of S. aureus subsp. anaerobius (22.58).The isolated bacteria were identified morphologically and biochemically.The results of animal pathogenicity test showed that C. pseudotuberculosis isolates were 100% pathogenic to guinea pigs and 80% of S.aureus isolates were pathogenic to mice, while all isolates of S. aureus subsp. anaerobius were pathogenic to mice. The dead animals showed haemorrhage and symptoms of septicaemia, C. pseudotuberculosis, S.aureus and S. aureus subsp. anaerobius were reisolated from the dead animals. Antimicrobial sensitivity of C. pseudotuberculosis , S. aureus and S. aureus subsp. anaerobius isolates to some antimicrobial agents which usually used in farms showed that from 90% to 100% of C. pseudotuberculosis isolates were sensitive to erythromycin, amoxicillin, tetracycline ,streptomycin, ampicillin and rifampicin while S. aureus isolates (from 55% to 66%) were sensitive to rifampicin,tetracycline ,erythromycin and streptomycin, while S. aureus subsp. anaerobius isolates were moderately resistant to all used antimicrobial agents.