Dr. W. Marvin Mackie, DVM
Owner/Director, Animal Birth Control
Los Angeles, CA

I've had several requests for the specific procedures I use for a scrotal castration. The following is a description of my technique.

In preparation, I clip the scrotum hair in the direction of the hair follicles, cranial to caudal. Applying the clipper blade in the opposite direction may cause the clippers to snag and scrape. I wash the area with chlorhexadine soap (I don't recommend alcohol).
I find a cloth drape with a 4" fenestration perfect for overlaying and tucking up under the caudal aspect of the scrotum.

I usually use a #15 blade as it affords me better control and helps prevent over-extending the incision. I make a single incision in the ventral cranial (anterior 1/3) of the scrotum, then force the testicle up tight to stretch the scrotum and cut to but not through the tunic. I approach as I would a closed castration. The scrotal skin is very elastic and will stretch to the extent you need. I tilt the pointy caudal aspect (the epidermis) upward and outward from the incision and then from under the testicle, “birth” it out. I finish off the small dogs as a closed castration. In all sizes, I use the power of the 4 - 0 stainless steel; circlage, cinch, crimp out at the knot drop. For dogs 40 pounds and up, I do an open castration.  I make sure to remove the tunic and place a ligature around the transected cremaster muscle, as it will bleed. 

For the second testicle, there is a median raphe that requires cutting in order to get into the other testicular compartment. Once there, repeat the testicular “birthing”.

I close all but the very small patient with a singular stainless steel (5 - 0, 34 ga.) intramuscularis mucosal buried stitch.

I have found one procedure vital in reducing post-surgery complications. I saturate a 1" gauze sponge with straight epinephrine, unfold it and insert the ends into the two testicular sockets, leaving a small bit out and visible through the cut. With my fingers, I squeeze the scrotum, commingling any blood into and with the epi in the gauze. I leave the gauze in place while I prepare at #14 needle with a small length of 5 – 0 stainless, then remove. Approximately 30 to 45 seconds have passed and upon removal the cavity is almost always dry. The small seepers have stopped and the intramuscularis mucosal has contracted in response to the epinephrine and is only ½ the length it had stretched during the birthing extractions of the testicles. Usually just the one stitch (mentioned above) is needed. I don’t even consider deep tissue stitches. Often, I'll add just a tiny amount of glue to keep the edges perfectly aligned. Very rarely do dogs bother the area, therefore, no e-collars are needed.