Page 317 - Veterinary Histology of Domestic Mammals and Birds, 5th Edition

Male reproductive system (organa genitalia masculina) 299

13.35 Longitudinal section of the glans
VetBooks.ir (ostium urethrae externum) (dog).
penis and external urethral orifice
Haematoxylin and eosin stain (x15).

13.36 Glans with keratinised papillae
(tomcat). Haematoxylin and eosin stain
(x250).

Ox and pig: The penis is of the fibro-elastic type. domestic species, the internal layer incorporates seba-
Elongation of the penis results primarily from straight- ceous and sweat glands and is mostly hairless. Together
ening of the sigmoid flexure. The tissue between the with the secretory product of the sebaceous glands, vacu-
vascular spaces consists mainly of fibro-elastic net- olar lipid degeneration in the epithelial cells gives rise to
works with few smooth muscle cells. The glans penis a fatty secretion (smegma praeputii). The lamina interna
contains a modestly developed subepithelial stratum contains numerous sensory receptors and abundant free
cavernosum that does not bring about enlargement of nerve endings.
the glans (Figures 13.35 and 13.36).
Species variation
Prepuce (praeputium) Ox, pig and dog: Lymphatic nodules are frequently
The prepuce is a fold of skin composed of an outer layer observed throughout the inner layer.
(lamina externa) and an inner or parietal layer (lamina Cat: The mucosal covering of the glans penis has small
interna). The inner layer is continuous with skin of the keratinised barbs (Figure 13.36).
free end of the penis.
The lamina externa has the typical structure of skin. Pig: The preputial diverticulum (diverticulum praepu-
It has a light covering of hair and, particularly towards the tiale) is lined by a deeply folded non-glandular mucosa.
ostium praeputiale, contains sebaceous glands. The lamina The contents of the diverticulum (cell debris and urine)
interna is lined by stratified squamous epithelium. In most produces a characteristic odour.

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