17 - Accessory Sex Glands

Question 1

What are accessory sex glands

Answer 1

Glands of the male reproductive tract that contribute the seminal plasma (fluid) to semen

Question 2

Name the four accessory sex glands

Answer 2

1. Ampulla
2. Vesicular gland
3. Prostate gland
4. Bulbourethral gland (cowpers)

Question 3

What is the ampulla

Answer 3

Enlargement of the ductus deferens that connects to urethra (not a gland)

Question 4

What is the vesicular gland

Answer 4

Seminal vesicles
Paired dorsal cranial glands that empty directly into urethra

Question 5

What is the prostate gland? Two forms

Answer 5

Gland found at the junction of the urinary bladder and urethra

Corpus prostate: lies outside the urethral muscle and is visible as a distinct structure
Disseminate prostate: gland tissue is distributed along the walls of urethra and is not distinct
Species dependent, some have one, the other, both

Question 6

What is the bulbourethral gland

Answer 6

Paired glands located on either side of the urethra, composed of connective tissue

Question 7

Ampulla exists in which species?

Answer 7

Most domestic species except boar and dog

Question 8

Species variations of the vesicular glands in bull+ram, boar, stallion

Answer 8

Boar+ram: lobed grape-like structure

Boar: large, well developed, contains visible fluid

Stallion: long, elongated, hollow pouch

Question 9

Species variation of the prostate gland in boar+stallion+dog, bull, ram+tom

Answer 9

B+S+D: visible corpus prostate structures

Bull: as both corpus and disseminate structures

Ram+Tom: only disseminate prostates structures

Question 10

Bulbourethral glands in the bull, ram, stallion and tom vs boar

Answer 10

B,R,S,T: small oval glands

Boar: large oblong gland, contains viscous gel fraction

Question 11

What accessory sex glands does the boar have? The dog?

Answer 11

Boar: no ampulla. large seminal vesicles. prostate. large bulbourethral glands

Dog: only prostate

slide 8

Question 12

Slides 9-13

Answer 12

Anatomy of diff species

Question 13

Contributions of ampulla, vesicular glands, prostate gland, and bulbourethral glands to seminal plasma

Answer 13

Ampulla: none (pre-ejaculate reservoir)

VG: produces most of the fluid for the ejaculate, contributes energy substrates and buffers the semen

PG: produces fluid, contributes inorganic ions (buffers the semen)

BG: produces fluid pre-ejaculate that flushes urine residues from urethra in most species, produces gel-fraction in boars

Question 14

What are the five functional components of seminal plasma

Answer 14

• energy substrates (fructose, sorbitol, GPC)
• sperm membrane maintenance (e.g. inositol)
• semen pH (slightly acidic: citric acid)
• buffering capacity – osmolarity (Ca, Na, K, Mg)
• proteins

Question 15

What species have the highest fructose in the seminal plasma? Why?

Answer 15

Bull and ram

Have very concentrated semen
Boar and stallion have more volume of seminal fluid per sperm

Question 16

Seminal plasma is rich in what types of proteins

Answer 16

Low molecular weight proteins (spermadhesins)

Question 17

Roles of seminal plasma proteins

Answer 17

• “decapacitation” factors
• protease inhibitors (prevent enzymes from breaking down sperm before it gets to fert site)
• immune suppression

Question 18

What species have the highest concentration of seminal proteins in their fluid

Answer 18

Bull then ram

Question 19

Slide 18

Answer 19

important