Abstract
Study on the body weight loss and the immune response when verotoxin was injected to the mouse was done. Mice were selected for high natural immunity (N line), high acquisition immunity (A line) and both the high natural and acquisition immunity (NA line), and non-selected control (C line) over 11 generations. The rate of body weight decrease and change of immunity during 4 days after verotoxin injection were measured and used as an index of disease resistance. No significant difference in weight loss was found among lines. After the verotoxin was vaccinated, a common tendency was found in the total number of white blood cells, phagocyte activity IgA, IgG, and IgM. TNF-α of A and N line had not changed but those of C and NA line significantly increased on the fourth day. The number of white blood cells, phagocyte activities, and antibody production (IgA, IgG, IgM) of the mice of selected lines indicated significantly high value compared with the control line (P<0.05). Moreover, differences of these immunity traits were apparent among selected lines. These differences in the immune response to the verotoxin among the selected lines of mice suggested the difference of immune response as model animals.
