Kif6-deficient and Kif9-deficient males show decreased sperm numbers. Related to Fig. 5, J and L. Sperms were released from cauda epididymis and imaged with a spinning disk confocal microscope at a fixed z-plane. (A and C) Representative images were from the cauda epididymis of littermates. (B and D) Quantification results from two mice of each genotype (5 full-size micrographs per mouse) were pooled together (mean ± SD plus sample dots) and subjected to unpaired two-tailed Student’s t test.