Repro pathology 3

What cells are present in the testicles and their functions?

• Germ cells- arranged in seminiferous tubules -> spermatogenesis

• Interstitial cells (Leydig cells): produce androgens under influence of LH

• Sertoli cells:

  • Support germ cells in seminiferous ductules

  • Secrete androgen binding protein into ductular lumen and so support spermatogenesis

List the developmental abnormalities of the testes

• Testicular hypoplasia

• Criptorchidism

What are the features of testicular hypoplasia?

• Uni or bilateral

• Can be linked to toxins/ hormonal imbalances/ Zn deficiencies/ hybrids

• Often associated with cryptorchid or chromasomal abnormalities

• 1° testicular hypoplasia occurs in several Swedish cattle breeds (recessive)

What are the effects of testicular hypoplasia?

Lack of spermatogenesis

What is cryptorchidism and its features?

Incomplete descent of testis

• Abdominal or inguinal

  • Abdominal prone to torsion and more freq tumours

• Bi- or unilateral

How does acute atrophy differ from chornic?

• Acute usually only histologically

  • hydropic degeneration, pyknosis, multinucleate giant cells, oligo- and aspermia

• Chronic reduced size and progressive fibrosis

List some of the causes of testicular atrophy

• Trauma

• Compression atrophy (testicular tumours)

• Circulatory disorders (eg. torsion: venous infarction-> haemorrhagic necrosis)

• Inflammation

• Infection

• Nutritional deficiencies (vits A + E)

• Hyperthermia

• Cryptorchidism

• Ionising radiation

• Hyperoestrogenism

• Pituitary alterations

• Senile atrophy

What are the features of testicular torsion?

• Rare

• Often as a sequelae to orchitis but also idiopathic

• Partial vs total

• Total = ischaemic necrosis

What are the names for inflammation of the testes?

• Orchitis

• Epididymitis

What are the general causes and features of orchitis and epididymitis

• Usually infection

• Purulent inflammation often due to streptococci, staph, e. coli, arcanobacterium pyogenes

• Often abscess formation

What are the routes of infection causing orchitis and epididymitis?

• haematogeneous-metastatic

• ascending infection

• external wounds

What causes orchitis and epididymitis in a horse?

• Salmonella abortus equi

• Equine viral arteritis (necrotising vasculitis)

What causes orchitis and epididymitis in a sheep?

• Corynebacterium pseudotuberculosis and

• Yersinia pseudotuberculosis (via ticks, infected from rodents)

• Brucella ovis (infectious epididymitis in sheep) -> chronic epididymitis

Suppurative epididymitis^

What causes orchitis and epididymitis in a dog?

• E. coli, Proteus

• Brucella canis:

  • Mainly chronic epididymitis; spermatic

  • Ag can get access to blood stream with macrophages, inducing Ab against sperm (= autoimmune disease)

^Chronic granulomatous orchitis

What causes orchitis and epididymitis in a cattle?

• brucellosis (B. abortus)

• tuberculosis

• chronic inflammation: in ruminants often associated with dystrophic calcification

^Chronic granulomatous orchitis

List the types of testicular tumours

• Seminoma (germ cell tumour)

• Sertoli cell tumour

• Interstitial (Leydig) cell tumour

• Teratoma (not in dogs, most frequent testicular tumours in horses)

What tumour is this?

Seminoma

• Gross: white and soft replaced most testicular parenchyma

• Hx: can be diffuse or intertubular (this one is diffuse), large round poorly differentiated cells

Benign

What tumour is this?

Sertoli cell tumour

Gross: firmer and better differentiated, white

Hx: intertubular tumour (can also be diffuse)

What clinical signs are associated with sertoli cell tumours?

• Signs of feminisation (oestrogen production from tumour)

• Bilateral alopecia

• Cutaneous hyperpigmentation

• Atrophy of opposite testis

• Pendulous prepuce

• Varying degrees of gynecomastia

  

• Attraction of male dogs

• Bone marrow suppression

• Squamous metaplasia of prostate gland epithelium

What is being shown here?

Seminiferous tubule atrophy

What are the gross features of an interstitial cell tumour?

• Soft, yellow to orange, well demarcated, bulging cut surface often with haemorrhage + cystic spaces

• Usually not larger than 1-2 cm in diameter (dog)

• Very rare metastases

• Usually benign

What can interstitial tumours cause?

• Inc androgen production maybe

• Inc incidence of tumours of androgen-responsive circumanal (perianal, hepatoid) glands

What tumours it this?

Gross: cysts, haemorrhage, yellow orange

Hx: haemorrhage, vacuolation (because steroid producting which presents as lipid)

What is this showing?

Testicular teratoma

What are the categories of pathology that affect the prostrate gland?

1. Atrophy

2. Squamous metaplasia

3. Inflammatory

4. Hyperplasia

5. Neoplasia

When is atrophy of the prostrate gland seen?

Most frequent after castration + oestrogen administration

When is squamous metaplasia of the prostrate gland seen?

With chronic infection + under the influence of oestrogen (Sertoli cell tumour), reversible

What can cause prostatitis?

• Most often in dogs, association with hyperplasia

• Non-specific (urinary) bacterial infections

• May lead to abscess

What is being shown here?

Prostatitis (large cavities where purulent exudate would have been)

What is prostatic hyperplasia?What does it result in?

• Diffuse expansion of the gland (dorsally)

• Results in compression of colon + difficult defecation

• Often with cyst formation + occ prostatitis

• Not necessarily premalignant

What is prostatic hyperplasia associated with?

increase in level of potent androgen (5-dihydrotestosterone) within gland

What is being shown here?

Prostatic hyperplasia

What is the most common prostatic tumour?

Usually adenocarcinoma or non-differentiated carcinoma

What are the general features of prostatic tumours?

• Occ in dogs (average age =9)

• Malignant

  • Metastasise to LN, urinary bladder and periproctal connective tissue

• Feels irregular upon palpation cf to hyperplasia

What is being shown?

Prostatic carcinoma

What are the anomalies of development?

• Hypospadias (ventral aspect)

• Epidspadias (dorsal aspect)

• Persistent frenulum

What is hypospadias/epispadias?

• Malformations of the urethral canal creating abnormal opening

• Predisposes to UTI

• Reccomend castration

  

What is a persistent frenulum?

• A band between the ventral raphe of the penis and the prepuce.

• Usually ruptures as puberty.

• Renders intromission impossible.

• Important in bulls and boars.

What are the different areas of inflammation of the peni?

• Phalloposthitis (entire penis + prepuce)

• Balanoposthitis (glans penis + prepuce)

[Note- Specific infections: see vagina (BHV-1, EHV-3) as many are spread venereally]

What are the benine tumours of the penis in bulls?

Fibropapilloma

• Caused by bovine papilloma virus type 1

What tumours affect the penis of stallions?

• Squamous cell papilloma (benign) (grows outwards, finger like projections)

  

• Squamous cell carcinoma (malignant)

  

• Sarcoids

  • Induced by bovine papillomavirus type 1