VITAMIN B12 CONTENT OF BLOOD FROM VARIOUS SPECIES

Abstract

The vit. B12 contents of human, dog, cotton rat, white rat, American albino mouse, Swiss albino mouse, cow, sheep, goat, pig, horse, rabbit, turtle, chicken and turkey bloods were detd. with Lactobacillus leichmannii 4797 (ATCC). Values obtained varied from 0.5-10.1 mug. B12/ml. whole blood. The B12 content of rabbit blood was particularly high when compared to that of other species. The vit. B12 activity of turtle, chicken and turkey blood was higher than that of other species tested with the exception of the rabbit, and this is probably due to the fact that these animals have nucleated erythrocytes and a part of the L. leichmannii activity of such .blood samples is due to thymidine. Autoclaving blood samples from the cotton rat, white rat, American albino mouse, Swiss albino mouse, calf, sheep, goat and rabbit at pH 12 destroyed all of the L. leichmannii activity; whereas, similar treatment of blood samples from the turtle, chicken and turkey destroyed only a portion of the vit. B12 activity.