Production and novel quantification of haemolysins produced by coagulase-negative staphylococci isolated from subclinical mastitis in sheep.
Coagulase-negative staphylococci producing cell-damaging toxins were isolated from the milk of sheep with subclinical mastitis. The haemolytic activity of Coagulase-negative staphylococcal strains was assessed on solid and liquid culture media. More than 61% and 76% of the tested strains on solid media produced evidence of alpha- and delta- haemolysins and more than 78% produced synergistic haemolysis. However almost all isolates producing haemolysin in liquid culture media produced only very few units of haemolysin compared to the positive control of five Coagulase-positive strains of staphylococci. It was concluded that solid media are better for classifying Coagulase-negative staphylococci as producers or not of haemolysins, and liquid media for measuring the size of this activity within the first few hours of intramammary infection.
Kanellos
T S
TS
Royal Veterinary College, London.
Burriel
A R
AR
D000818:Animals; D003030:Coagulase / Q000172:deficiency; D003470:Culture Media; D004797:Enzyme-Linked Immunosorbent Assay / Q000662:veterinary; D004912:Erythrocytes / Q000378:metabolism / Q000382:microbiology; D005260:Female; D006454:Hemoglobins / Q000378:metabolism; D006460:Hemolysin Proteins / Q000096:biosynthesis* / Q000378:metabolism; D008413:Mastitis / Q000378:metabolism / Q000382:microbiology*; D008892:Milk / Q000382:microbiology; D012756:Sheep; D012757:Sheep Diseases / Q000378:metabolism / Q000382:microbiology*; D013056:Spectrophotometry, Ultraviolet / Q000662:veterinary; D013203:Staphylococcal Infections / Q000378:metabolism / Q000382:microbiology / Q000662:veterinary*; D013210:Staphylococcus / Q000201:enzymology / Q000378:metabolism*
D003030:Coagulase; D003470:Culture Media; D006454:Hemoglobins; D006460:Hemolysin Proteins