Repro - Sexual Behaviour

Question 1

What are the three types of reproductive behaviours in females

Answer 1

Attractivity (vocalization, posture, pheromones)

Proceptivity (stimulates the male)

Receptivity (ensuring insemination)

Question 2

what are the three types of reproductive behaviour in males

Answer 2

Precopulatory (everything up to erection and penile protrusion)

Copulatory (doing the deed)

Postcopulatory (refractory period and memory)

Question 3

What acts as the stimuli for arousal?

Answer 3

male pheromones

Question 4

what are the two important male pheromones, and what effect do they have on sows?

Answer 4

The important male pheromones are 3 α androstenol and 5 α androstenone.

These are the pheromones that induce rigidity stance/reflex in sows

Question 5

What pheromone do female dogs produce, and what effect does it have

Answer 5

Female dogs produce methyl-p-hydroxybenzoate, a pheromone from vaginal secretions.

It attracts male dogs

Question 6

what is the flehmen behavior

Answer 6

found in both sexes, occurs when the upper lip is lifted to create negative pressure in the nasopalatine duct. Allows animal to sense less volatile pheromones

Question 7

What is the path of a pheromone as it reaches the brain?

Answer 7

Pheromone -> nasopalatine duct ->vomaronasal organ -> higher brain centers

Question 8

Give an example of a visual stimuli for sexual behaviour

Answer 8

Training of bulls for semen collection using artificial vagina includes allowing them to watch how other bulls mount and ejaculate

Question 9

what hormone plays a major role in regulating sexual behaviour in both sexes

Answer 9

estradiol

Question 10

what is required for the hypothalamus to receive sensory stimuli regarding sexual behaviour

Answer 10

the hypothalamus must be sensitized by estradiol (E2)

Question 11

if estradiol is the female sex hormone, how do males stimulate their hypothalamus?

Answer 11

they can convert testosterone into estradiol

Question 12

how can males initiate sexual behaviour at any time

Answer 12

they have a constant supply of E2 (due to testosterone being in constant supply) so they can sensitize their hypothalamus to process sexual stimuli whenever they want

Question 13

how is mounting inititated?

Answer 13

Sensitization of hypothalamus by estradiol >
hypothalamus accepts sensory stimuli >
Neurotransmitters > midbrain translates these
neuropeptide signals into a response >
integration of signals in the medulla > spinal cord
communicates these signals to specific muscles
(via motor neurons) for lordosis/mounting

Question 14

One of your clients wanted to have a chat with you regarding the poor libido (desire and ability to mate) of a bull he used during the last breeding season. The client wanted to treat this bull, improve libido and use the bull again during this breeding season. Think about how above summarized principles could be utilized to address this clinical issue.

Answer 14

I THINK you could just give the bull E2 (pls fact check me, I didnt put this in my notes)

Question 15

does the size of a bull penis increase during erection, and why/why not?

Answer 15

No, but the pressure increases. this is because the tunica albuginea completely covers the erectile tissue (corpus cavernosum and corpus spongiosum) in fibroelastic penises

Question 16

what are the cavernosus spaces in erectile tissue called

Answer 16

corporal sinusoids

Question 17

what are the two types of innervations to the smooth muscles of the corporal sinusoids>

Answer 17

adrenergic and NANC (non adrenergic, non-cholinergic parasympathetic)

Question 18

what innervation to the penis is dominant during normal conditions

Answer 18

adrenergic via NE, resulting in vasocontriction (flaccid dick)

Question 19

What innervation to the penis is dominant when there is erotogenic stimuli

Answer 19

NANC via NO

Question 20

How does NO release by NANC result in erection (Im sorry, this is a long one)

Answer 20

No converts GTP into cGMP by activating guanlyate cyclase. cGMP relaxes smooth muscles around sinusoidal spaces, leading to accumulation of blood. dilation of sinusoidal spaces obliterates venous return from the penis, which will cause retention of blood in the sinusoidal spaces. In addition, contraction of Ischiocavernosus muscle also contributes to venous stasis. Relaxation of retractor penis muscle (innervated by NANC) causes protrusion of the penis

Question 21

how does viagra work

Answer 21

viagra contains sildenafil, which is a PDE inhibitor.

Question 22

How do PDE’s stop erections

Answer 22

by converting cGMP back into GMP

Question 23

what is mounting

Answer 23

postural adjustments for intromission

Question 24

what is intromission

Answer 24

entry of penis into vagina

Question 25

what is emission

Answer 25

movement of sperm from the tail of the epididymis and seminal fluids from the accessory glandsd into the pelvic urethra (colliculus seminalis)

Question 26

what is ejaculation

Answer 26

reflex expulsion of sperm and accessory gland fluids (semen) from the male repro system

Question 27

what are the 5 steps to emission

Answer 27

1. sensory stimulation
2. stimulation of supraoptic and paraventricular nuclei
3. oxytocin
4. contraction of smooth muscle in the caudal epididymis and ductus deferens
5. release of sperm and seminal fluid into pelvic urethra

Question 28

t/f emission only occurs before ejaculation

Answer 28

false, it also occurs during

Question 29

what nerve brings sensory info from the glans penis to the spinal cord>

Answer 29

internal pudendal nerve

Question 30

what plexus fires motor neurons that innervate the urethralis, ischiocavernosus, and bulbospongiosus muscles to cause ejaculation

Answer 30

hypogastric plexus

Question 31

what is a copulatory tie?

Answer 31

found in canine species, when the copulating pair basically get stuck together because the bulbis glandis swells inside the vagina and prevents the male dog from pulling out

Question 32

what structure allows intromission before erection in dogs

Answer 32

os penis

Question 33

in first stage canine coitus, what fractions (and their components) are released

Answer 33

fraction 1 (prostatic fluid) and fraction 2 (sperm rich)

Question 34

in second stage canine coitus, what fraction (and its components) are released

Answer 34

fraction 3 (prostatic fluid)

Question 36

what are the three anatomically distinct regions of a dog penis

Answer 36

glans penis, pars longa glandis, and bulbus glandis