Studies conducted in Western countries so maybe sheep blood is reachable than other blood?
Earlier bacteria were characterized for identification and diagnostic purposes using sheep blood agar. If one wishes to use some other species blood in blood agar medium, it's essential to study the hemolysis of standard ATCC strains and if they show similar type of hemolysis as with that of sheep blood then source of blood for blood agar should not be an issue.
We don't prefer human blood due to presence of antibody which can prevent the growth of many bacteria.
Sheep blood has been preffered source in the Blood agar due to the fact that sheep RBCs are most sensitive to the the hemolytic toxins released by bacterial cells thus causing hemolytic zones around the colonies over the period of time. Moreover, sheep blood is already standerdized with 5-10% concentration and prefferably defibrinated blood is used in the making of media other wise the anticoagulants (Heparin, EDTA etc) also affect the hemolysis pattern on blood agar.
Even Staphylococcus spp. did not show beta hemolytic typical characteristic if the source of Blood is rabbit or cattle or Human RBCs
Pig and Goat Blood as Substitutes for Sheep Blood in Blood Supplemented Agar Media.
Horse and sheep blood are the most widely used animal blood products in culture media. The choice of animal is largely traditional, with the USA and much of continental Europe preferring sheep blood, whilst the UK and Commonwealth partners prefer horse blood.
Availability of sheep blood is one reason (Need not to take consent to draw blood). Safety (free from HIV, HBV or HCV like organisms), another important reason. Blood from specially breed sheep for microbiological purpose are free from antibiotics which interrupt the growth of bacteria. Because of hemolysis which occur more frequently than to other animals blood, may be a reason but, not sure.
Earlier bacteria were characterized for identification and diagnostic purposes using sheep blood agar. If one wishes to use some other species blood in blood agar medium, it's essential to study the hemolysis of standard ATCC strains and if they show similar type of hemolysis as with that of sheep blood then source of blood for blood agar should not be an issue.
We don't prefer human blood due to presence of antibody which can prevent the growth of many bacteria.
Sheep blood has been preffered source in the Blood agar due to the fact that sheep RBCs are most sensitive to the the hemolytic toxins released by bacterial cells thus causing hemolytic zones around the colonies over the period of time. Moreover, sheep blood is already standerdized with 5-10% concentration and prefferably defibrinated blood is used in the making of media other wise the anticoagulants (Heparin, EDTA etc) also affect the hemolysis pattern on blood agar.
Even Staphylococcus spp. did not show beta hemolytic typical characteristic if the source of Blood is rabbit or cattle or Human RBCs
Pig and Goat Blood as Substitutes for Sheep Blood in Blood Supplemented Agar Media.
Horse and sheep blood are the most widely used animal blood products in culture media. The choice of animal is largely traditional, with the USA and much of continental Europe preferring sheep blood, whilst the UK and Commonwealth partners prefer horse blood.
Availability of sheep blood is one reason (Need not to take consent to draw blood). Safety (free from HIV, HBV or HCV like organisms), another important reason. Blood from specially breed sheep for microbiological purpose are free from antibiotics which interrupt the growth of bacteria. Because of hemolysis which occur more frequently than to other animals blood, may be a reason but, not sure.
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