Testes, epididymis, and scrotum Flashcards
What is the name of the attachment of the testes and epididymis to the vaginal tunic and spermatic fascia?
Ligament of the tail of the epididymis.
Does the vas deferens cross ventral or dorsal to the ureters at the level of the lateral ligament of the bladder?
Ventral.
What structures does the spermatic cord contain?
Ductus deferens and its associated artery and vein, testicular artery, pampiniform plexus, lymphatic vessels, nerves and cremaster muscle.
From which muscle is the cremaster muscle formed?
The internal abdominal oblique.
What is the vascular supply of the testis and epididymis?
Testicles: Testicular arteries from the aorta, venous drainage to the vena cava (right) or left renal vein (left).
Epididymis: Ductus deferens arteries from the prostatic artery (branch of the internal iliac artery).
What is the lymphatic drainage of the testicles?
Lumbar lymph nodes.
What are the three layers of the scrotum?
Skin, tunica dartos, scrotal fascia.
What is the vascular supply to the scrotum?
The external pudendal artery. Scrotal veins correspond to arterial supply.
What is the lymphatic drainage of the scrotum?
The superficial inguinal lymph nodes.
What are the three cells of the testes?
- Spermatogenic
- Sertoli: support the development and maturation of sperm. Stimulated by FSH.
- Leydig (interstitial cells): produce testosterone, controlled by LH in the anterior pituitary gland.
What are the accessory sex glands of the dog and cat?
Dog: prostate.
Cat: prostate and bulbourethral glands.
The prostate secretes thin, milky, alkaline seminal fluid that aids survival of spermatozoa.
How can a bilateral cryptorchid dog be differentiated from a bilateral anorchid or castrated dog?
After administration of hCG (which has a similar function as LH) should see a rapid rise in plasma testosterone levels if a testicle is present.
How long after castration should the penile spines on a cat disappear?
6-weeks
At what age can diagnosis of cryptorchidism be definitively made?
6 months.
Why is surgical descensus and orchiopexy not recommended for treatment of cryptorchidism?
Likely heritable component, therefore castration is recommended.
What is the rate of neoplastic transformation of a canine cryptorchid testicle?
9-14%
What concurrent congenital abnormalities have been reported in dogs and cats with cryptorchidism?
Dogs: Hip dysplasia, patellar luxation, defects of the penis and prepuce, and umbilical hernia.
Cats: Patellar luxation, shortened or kinked tail, tetralogy of Fallot, tarsal deformities, microphthalmia, and upper eyelid agenesis.
What are some causes of orchitis?
Bacterial (Brucella canis, Klebsiella), viral (canine distemper), fungal (Rhodotorula glutinis), or rickettsial (Rocky Mountain spotted fever).
How can orchitis be differentiated from testicular neoplasia or torsion?
History, clinical findings, blood work indices, testicular ultrasonography, fine needle aspiration (FNA), testicular biopsy, and orchiectomy.
What diagnostics can be useful for the diagnosis of testicular torsion?
Generally intraabdominal cryptorchid testicle. Can be identified by abdominal radiographs, ultrasound +/- Doppler, abdominal exploratory surgery.
What are the most common canine testicular cell tumours?
Interstitial (Leydig) cell tumours, Sertoli cell tumours, seminomas (equal frequency).
How much is the risk of testicular neoplasia increased in dogs with concurrent inguinal hernia?
4.7 times.
What percentage of dogs with Sertoli cell tumours present with feminization syndrome?
16-39%. Can cause fatal myelotoxicosis (anemia, leukopenia, thrombocytopenia).
What is the metastatic rate for Sertoli cell tumours in dogs?
2-10% (regional lymph nodes, lungs, kidneys, spleen, pancreas, liver).
