investigation on the incidence, diagnostic, possibilities and design of prophylactic treatment in an outbreak of bacterial haemorrhagic septicemia of carp

Abstract

The investigations carried out on a sample of 53 breeders (31 females and 22 males), in a fishing farm of Suatu village, County of Cluj, concerning the incidence of hemorrhagic bacterial septicaemia, diagnosis and profilactico-therapeutic possibilities. Results highlights a incidence of bacteriosis differentiated according to the category of breeders, 54.8% in females and 36.3% in males. Necropsy examination carried out on 3 specimen of suspected bacteriosis, highlights the presence of hemorrhagic skin lesions, which are dotted or diffuse, respectively musculo-cutaneous necrosis and ulcers. Regarding the internal injuries, opening of the body cavity, revealed consistency changes and septicemy form in major internal organs, as well as the presence of a liquid hollow looking sanguinolent. The bacterioscopic examination of smears from the pathologic material (skin surface end internal samples) and colored with the Gram method, reveled bacterial microflora, represented by coccobacillus and straight bacilli or slightly curved, both Gram negative. Furthermore, the bacteriological (culture) exam performed on usual and selective culture mediae, distinguishes the isolation of pure culture bacteriae belonging to the genus Aeromonas. The exam of biochemical traits, with the aid of API 20 E multitest determines that the isolated strains of Aeromonas spp. belong to the species Aeromonas hydrophila, indicted in the emergence and evolution of the bacterial of haemorrhagic septicaemia. Testing strains sensitivity to antibiotics and chemotherapy (through antibiograma level), reflects the isolated bacteria’s values of sensitivity in decreasing order: amoxicillin, oxytetracycline, florfenicol and enrofloxacilin. However, reduced sensitivity was recorded to tetracycline and ampicillin and resistance to erythromycin. Â