Publication Date


Advisor(s) - Committee Chair

Gordon Jones, James Skean, Elmer Gray

Degree Program

Department of Agriculture

Degree Type

Master of Science


Two inbred strains of mice, BALB/c and C57BL, were crossbred to produce Fl hybrids. This breeding scheme ensured a high degree of genetic heterozygosity as exemplified by the fact that the average weight of the Fl hybrids at 10 weeks of age was 10.1 percent greater that that of their contemporaries in the inbred parental strains.

The three lines of mice were then challenged with a 0.5 ml intraperitoneal injection of two-percent sheep red blood cells (SRBC). After a 15-day period the mice were bled and their sera were microtitrated for anti-SRBC agglutinin and the titers statistically analyzed. The Fl mice were found to exhibit a highly significant (P < 0.0001) difference in serum antibody titers over both parental strains. Highly significant differences were also shown between the parental strains, the BALB/c mice being superior to the C57BL in antibody production to SRBC.

The results of this work indicate a 177.1 percent degree of heterosis in the immune response of the Fl hybrid mice over that of their inbred contemporaries. These findings, coupled with general knowledge of animal genetics and performance, may indicate that the increased immunocompetence of the crossbred mice is directly related to their increased rate of growth.


Agriculture | Animal Sciences | Life Sciences | Other Animal Sciences