Differential interference microscopy (DIC) of bull spermatozoa
Keywords: bovine, BSE, bull , bovine, DIC, interference, microscopy, Nomarski, sperm,
Nomarski Interference Contrast (NIC) or differential interference contrast microscopy (DIC) use here to examine bovine sperm. The advantage of this technique is that no staining is required so live spermatozoa can be examined.
On the left side of the image, two abnormal spermatozoa are present, one with a bent midpiece and the other with a piriform (pear-shaped) head. At lower left and upper right there are two apparently normal spermatozoa. In the middle and bottom of the image, the spermatozooan has a coiled midpiece and tail, reminiscent of the so-called "Dag defect". At lower right there is an enlargement at the end of the midpiece; probably an expanded portion of the mitochondrial sheath. Because this could also be a small midpiece droplet, one could only verify that diagnosis via electron microscopy. The end-pieces of the spermatozoa (the portion of the tail beyond the main piece, at the very end of the tail) are easily seen in this image.
