Agriculture Reference
In-Depth Information
Figure 6.31
The
kidney: A. Left
kidney, ventral
aspect; B. Right
kidney, ventral
aspect;
C. Longitudinal
section.
penis, and the copulatory organ (the penis) within the
prepuce. There are also annex glands to the urethra.
dorsally, a tail oriented ventrally, two aspects (lateral and
medial), and two borders (cranial free and caudal where
the epididymis is connected to the testicle) (Figure 6.32).
Each testicle is surrounded by a fi brous tunic called albu-
ginea, is inextensible, and continues inside the organ as
interlobular septa. The stroma (the main substance) of the
testicle is divided by the septa into lobules. The septa
connect with each other and form the mediastinum testis.
Numerous seminiferous tubules fi ll the lobules and inter-
connect inside the mediastinum testis in a network called
rete testis.
The testicles are protected by multiple layers of tunics
called testicular tunics. Some of these layers are brought
T
HE
T
ESTICLES
As the essential male reproductive glands, the testicles
have two functions: to produce spermatozoa able to fertil-
ize the ovules, and to secrete testosterone, the male
hormone. (As a curiosity, one cubic millimeter of semen
of the goat contains 2,500,000 spermatozoa.)
Ovoid shaped, the testicles are located in a vertical posi-
tion within the testicular tunics on the ventral and caudal
aspects of the abdomen, in the inguinal region (see Figure
6.3). Each testicle weighs 130-160 g, has a head oriented
