**Abstract**

The prostate gland is the only male accessory gland in dogs and is responsible for secreting the prostatic fluid. Morphologically, the canine prostate gland lacks differentiation into zones, presenting a uniform parenchyma along the longitudinal axis. The luminal epithelial cells secrete a liquid rich in calcium, citric acid, simple sugars, and different enzymes as a component of the seminal plasma. Since the prostatic diseases are very common in small animal practice, there are many information regarding mechanisms of the different prostatic conditions and lack of information regarding the anatomy, histology, and physiology of the canine prostate gland. Thus, this chapter aims to meticulously describe the anatomy, histology, and physiology of the canine prostate gland.

**Keywords:** dog, prostatic fluid, prostatic tissue, secretory cells, urogenital system

### **1. Introduction**

The prostate gland is the only male accessory gland in dogs, having an important role in the secretion of seminal plasma components. It is a bilobed, oval gland located in the pelvic cavity of adult dogs through which passes the urethra and the vas deferens, where the sperm are carried to the urethra. The prostate communicates with the urethra through several openings along the entire prostatic urethra through which the seminal plasma is secreted. Prostate diseases are extremely common in dogs, so their study is of great importance to better understand these conditions [1, 2]. The castration status is very important for the development of different prostatic disorders [3]. Usually, in developed countries, such as Canada, the United States, and Australia, the castration is very common. Due to castration and low levels of androgen hormones, the prostatic epithelium can be atrophic [1, 2]. On the other hand, the South America countries do not castrate dogs. Then, prostatic disorders such as benign prostatic hyperplasia (BPH) and prostatitis have high incidence [4]. Thus, the knowledge of the anatomy, histology, physiology, and pathology of the canine prostate gland is essential for the better approach of the canine patients.
