agr 506 Exam 3

Stages of Reproductive Behavior in the Male

-precopulatory stage

-copulatory stage

-postcopulatory stage

What is involved in precopulatory behavior?

searching for sexual partner

courtship

sexual arousal

erection

penile protrusion

What is involved in copulatory behavior?

mounting

intromission

ejaculation

What is involved in postcopulatory behavior?

dismount

refractory period

memory

Attractivity

-behaviors and other signals that serve to attract males

Ex: postures, vocalizations, behaviors, chemical cues, etc

Proceptivity

-behaviors exhibited by females towards males that stimulate male to copulate or that reinstate sexual behavior after copulation

Ex: head butting male or mounting male

Receptivity

-copulatory behavior of females that ensures insemination

Ex: immobility or standing response, tail deviation, backing up toward male.

Behaviors of a Female in Estrus

-increased locomotion

-milling around

-exploration

-increased vocalization and agonistic behavior toward other females can be observed

What is common across almost all species in females estrus?

There is a marked increase physical activity that accompanies time of ovulation in almost all species.

Courtship stimuli

-sniffing vulva by male

-urination by female in presence of male

-Flehman behavior

-chin resting

-circling

-increased phonation

In courtship stimuli what are important?

Visual, olfactory, and auditory stimuli are ALL important!

What is Lordosis?

-mating posture done by the female

-motor response associated with the "willingness" to mate

What will negative experiences during breeding result in?

less enthusiasm, inhibition of reproductive behavior.

What will positive experiences during breeding result in?

promotion of reproductive behavior.

-need to provide male with positive stimuli.

What is required for normal reproductive behavior?

Presence of gonadal steroids (estradiol and testosterone)

What are two examples of reproductive steroids?

estradiol and testosterone

What effect does removal of gonadal steroids have on an animal?

remove (castrate, ovariectomy) and will not display any of these reproductive behaviors

What happens with artificial induction of reproductive behaviors?

administer certain gonadal steroids to produce the sought after behaviors.

Females experience high estradiol levels during what phase only?

follicular phase

During what phase do female display sexual receptivity only?

estrus

Which behaviors are associated with Search in females?

increased locomotion, increased vocalization

What behaviors are associated with Courtship in females?

increased grooming, urination in the presence of a male, and immobile stance

What behaviors are associated with Consummation in females?

immobile stance, lordosis, tail deflected to one side

What behaviors are associated with Search in males?

Flehman response, approaching females

What behaviors are associated with Courtship in males?

sniffing/licking female genital region, excitement, chin resting

What behaviors are associated with Consummation in males?

penile protrusion, mounting, +/- dripping seminal fluid

Flehman Response

-assists the male in identifying mating opportunities

-vomeronasal organ/accessory olfactory organ

-bull, ram, stallion, and boar

What is the duration of copulation between sheep?

1 to 2 seconds

What is the duration of copulation between cattle?

1 to 3 seconds

What is the duration of copulation between horses?

20 to 60 seconds

What is the duration of copulation between pigs?

5 to 20 minutes

What is the site of semen deposition in the ewe?

external cervical os

What is the site of semen deposition in the cow?

fornix vagina

What is the site of semen deposition in the mare?

external cervical os, but semen enters uterus at high pressure.

What is the site of semen deposition in the sow?

cervix and uterus

Sexual Stimulation

the presentation of a stimulus situation that will achieve mounting and ejaculation

What can affect the efficacy of sexual stimulation before reaching sexual satiation?

introduction of a novel stimulus animal, changing the stimulus setting, or both

Methods of Semen Collection

-electroejaculation

-artificial vagina

-surrogate stimulus animal

-female condom

In which species is the semen deposited into the vagina?

cow, sheep, rabbit, primates, dog, cat

In which species is the semen not deposited in the vagina?

pigs (cervix), horse (cervical lumen)

Spermatozoal Loss

the degree to which spermatozoa are lost from the female tract depends on the physical nature of the ejaculate and the site of deposition

Spermatozoal Transport

Consists of a rapid and sustained phase

For spermatozoal transport what is found in the oviducts?

Within a few minutes after copulation, spermatozoa can be found in the oviducts (not viable)

What is sustained phase spermatozoa in transport?

sperm move into isthmus and attach to oviductal epithelium; temporarily dock to the epithelium.

What is an important step for sperm survival in transport?

docking is crucial to sperm survival and elicits a signal cascade in sperm that promotes viability.

What serves as the major barrier to spermatozoal transport?

cervix

The cervix can also serve as a _______ for spermatozoa.

reservoir

______ is a complex process that involves a cascade of events.

fertilization

What facilitates sperm-oocyte contact?

spermatozoa hyperactivity

Primary zone binding region

responsible for adherence of spermatozoa to the zona pellucida

Second binding site

acrosome reaction promoting ligand

Acrosome reaction

-enables spermatozoa to penetrate the zona pellucida

-modifies the equatorial segment so it can later fuse with plasma membrane of oocyte

What is the purpose of acrosomal enzymes?

allows the spermatozoa to digest its way through the zone pellucida

Polyspermy

multiple sperm fertilizing an oocyte

What is the result of polyspermy?

embryo death

How does the oocyte prevent polyspermy?

zona pellucida and vitelline blocks

What is the fertile period?

the fertile lifespan of sperm after deposition in female tract varies among species.

Transcervical Insemination

semen delivered by pipette to penetrate and bypass cervix

Intracervical Insemination

Semen is delivered into the cranial half of the cervix and flows directly into uterine horns (swine)

Intravaginal Insemination

semen is deposited into the cranial vagina (cats and dogs)

Bovine AI

-depositing into cervix leads to greater retrograde loss

-depositing into single uterine horn does not benefit from uterine body (intercornual transport - redistribute into both uterine horns)

Puerperium

the period after parturition when the reproductive tract returns to nonpregnant conditions

Uterine Involution

-decreased uterine size

-decreased uterine volume

-expulsion of lochia

-endometrial repair

What brings about reduction in uterine size and volume?

myometrial contractions

Postpartum suckling causes the release of what hormone?

oxytocin

Lochia

-during and after myometrial contractions, a bloody fluid is discharged from the tract

-contains remnants of fetal placenta and endometrial tissue

-physiologically normal in all species

Which species undergoes caruncle repair?

cows

What does caruncle repair require?

vasoconstriction, necrosis, and sloughing of tissue

Steps of caruncle repair

-vasoconstriction takes place in the stalk of the maternal caruncle

-necrosis follows

-some blood is released from the stalk and produces a blood-tinged fluid

-chunks of caruncle will detach and leave blood vessels exposed

-repair is initiated and caruncle will be covered with endometrial epithelium again

Postpartum Bacterial Contamination

-common in domestic animals

-not always associated with pathology

-normal postpartum events tend to eliminate bacterial flora

What are some predisposing factors to postpartum uterine infections?

-retained fetal membranes

-dystocia

-delay in lochial exposure

What are some possible results of postpartum uterine infections?

-prolong uterine involution

-prolong puerperium

-delay subsequent pregnancies

What is the most important natural factor that aids in elimination of uterine bacterial contamination?

return to cyclicity

Lactation

synthesis, secretion, and removal of milk from the mammary gland

What is the only behavioral requirement of neonates?

suckling the dam

Mammary glands are ________.

sophisticated sweat glands

When do postnatal changes in the mammary gland occur?

-between birth and puberty

-between puberty and pregnancy

-during pregnancy

-during lactation

-during involution

What is postnatal growth of mammary glands mediated by?

endocrine system

When does the female gain the ability to synthesize and secrete milk?

she has reached puberty, becomes pregnant, and has given birth to offspring

When is there significant growth of the mammary glands?

between puberty and pregnancy

When does final mammary development occur?

during pregnancy

How many teats does a cow or camel have and where are they located?

4 inguinal

How many teats does a ewe, goat, or mare have and where are they located?

2 inguinal

How many teats do sows have?

lots

How many teats does a bitch or queen have?

Eight ish

How many teats do primates or elephants have and where are they located?

2 thoracic

What provides immunoprotection and nutrition for the neonate?

lactation

Colostrum

-first secretions from the mammary gland

-critical to neonatal survival

-contains immunoglobulins (antibodies) for passive immunity

Animals with _______________ placenta (ruminants, etc.) cannot transfer immunoglobulins in-utero (placenta is a barrier).

epitheliochorial

Animals with ________ placentas have placental transfer of immunoglobulins from dam to fetus.

hemochorial

Milk contains _____ and ____.

hormones, growth factors

Milk Ejection

transfers milk from mammary alveoli into the ducts, then cesterns and into teat or nipples where it can be removed by suckling neonate

Teat

canal

Nipple

multiple ducts

Milk ejection requires:

- sensory activation (auditory, tactile, and visual)

- neural activation of the hypothalamus

- oxytocin release into the blood

- contraction of the myoepithelial cells

- mechanical transfer of milk from alveoli into ducts and finally into the teat/nipple

Non-cornified cells

parabasal and intermediate

Cornified cells

superficial and anuclear

Which cells are present when estrogen is low (anestrus and diestrus)?

non-cornified

Which cells are present when estrogen is high (proestrus and estrus)?

cornified

What is the most defining characteristic of cytologic estrus?

the predominance of superficial cells