Uncontrolled use of antibiotics in the treatment of calves suffering from gastroenteritis and dairy cows suffering from mastitis, created in pathogenic staphylococci enterotoxin producers some resistance to these drugs. These pathogens enterotoxin producers are often excreted with milk from cows with mastitis. That is why the specific and topical issue remains the isolation and identification of strains producing staphylococcal enterotoxin from cow milk and faeces of calves suffering from enteritis. Given all this, we have set a goal to get staphylococcal enterotoxin type D for use as mastitis diagnostic kit and enteritis and antigen for obtaining the antiserum. To obtain the staphylococcal enterotoxin type D we used strain S. aureus No. 494 (ATSS23235) courtesy offered by Dr. FC Fluer from Institute of Experimental Medicine, NF Gamaley, Medical Academy (USSR). Verification of the specificity of the enterotoxin) was performed using 5 strains of S.aureus producing different enterotoxins (enterotoxin-A; enterotoxin-B; enterotoxin C-1 ; C-2 and enterotoxin-E) as well as non-enterotoxigenic staphylococcal strain (S. aureus Wood 46). In addition to the staphylococcal strains, five strains of Escherichia coli, producing thermostable and thermolabile enterotoxins were also used in the experiment. The method of purification of enterotoxin-D by precipitation twice chromatography on km-cellulose and gel filtration on Sephadex G-75 allows to obtain pure enterotoxin-D having the biological properties, immunological and antigenic characteristics. Immunization of rabbits with purified enterotoxin-D associated with incomplete Freund's adjuvant provides antiserum very active and specific.

Avian influenza (AI) is a contagious infectious