Morphological aspects of the spermatic cord in mules (Equus asinus x Equus caballus)

Abstract

In a morphologic study of 15 spermatic cord pairs of male mules (Equus asinus x Equus caballus), histology showed in 5 pairs that its components are involved in a thin capsule of a dense connective tissue, covered by a mesothelium. Underneath the capsule, in a close relation, we identified the internal cremaster muscle. This muscle goes with mesoductus. The funicular capsule and muscular tissue form a few small plicae. The funicular vessels (testicular artery and veins) are wrapped up in loose conjunctive tissue prevailing collagen fibers. The funicular part of the testicular artery is convoluted. It shows a thick tunica média vasorum supported by a net of reticular fibers; tunica intima vasorum is build up endothelium, thin connective tissue and a well defined internal elastic layer; tunica externa vasorum with the connective tissue becoming part of intervascular connective tissue. The testicular veins constituted a very elaborated close-meshed pampiniform plexus in which contortions of the artery are embedded. These veins have a medial tunic formed by elastic and reticular fibers, with a few muscular fibers without valves. The part of testicular artery model obtained with Neoprene latex 450 in 20 preparations, corresponding to 10 pairs of spermatic cords, have mean, maximum, and minimum lengths, respectively, of 58,2 cm, 81 cm, and 44 cm to the right side and 66,5 cm, 96 cm, and 51 cm to the left side.