The parasitic ecology of the rodent mite Myobia musculi. II. Genetic factors.

Mice of 4 strains, C57BL/6J, CD2F1(BALB/cCum female times DBA/2Cum male), BRVR/SrCr and BSVS/SrCr, were monospecifically infested with an equal number of Myobia musculi. A single skin field (7mm diam) in the dorsal midline slightly posterior to the eyes was used for periodic observation of mite populations. Mite counts were made by direct microscopic examination of the skin field at 10-da intervals. Data were obtained on mice thus infested and observed for 130 da. Between-strain comparisons differed significantly in the number of Myobia maintained in all cases except between BRVR and BSVS strains. Factors bearing on heritable differences in susceptibility were discussed.