ANSC 107 Exam 3 ramsey

Spermatogenesis

Production and maintenance of sperm supply

Overall functions of the male

Produce and maintain sperm supply, detect females in estrus, inseminate females and fertilize the female gamete

Spermatic cord

Contains vas deferens, pampiniform plexus, and external cremaster muscle nerves

Vas Deferens

Transport sperm during ejaculation

Seminiferous Tubule

sperm producing cells- true germinal epithelium

Corpus Epididymis

Responsible for maturation of spermatozoa

Cauda Epididymis

Final maturation and storage, only sperm capable of fertilization

Tunica Albuginea

Connective tissue which holds testis together

Caput Epididymis

Function in maturation of spermatozoa, fluid absorbtion

Sertoli Cells

Support spermatogenesis

Leydig Cells

Testosterone synthesis

Function of Testes

1. Produce sperm

2. transport sperm out of testis

3. Produce testosterone

Testosterone function

1. Stimulate secondary sex characteristics, muscle development, and accessory glands

2. Maintains libido

3. Maintain function of male reproductive tract, penis, and muscles for ejaculation

Thermoregulation

Temperatures 3-5 degrees celsius less than the body temperature are required for spermatogenesis to occur

Scrotal properties that facilitate thermoregulation

1. Location of testis- outside away from the body air circulation

2. Low insulation- thin skin, low subcutaneous fat or hair

Pampiniform plexus

Counter-current heat exchange causes a cooling of arterial blood supply

Scrotum, testis, and spermatic cord

What all is involved in thermoregulation?

Cryptorchidism

lack of testis descent into scrotum and this thermoregulation is absent

Bilateral

Sterile, no spermatogenesis, testosterone is produced

Unilateral

Fertile, reduce sperm producing capacity

Functions of the epididymis

1. transport sperm

2. maturation of sperm in caput to corpus region

3. storage of sperm- cauda

Fate of unejaculated sperm

1. resorbed by excurrent duct system

2. sperm lost in urine

3. masturbation loss of sperm

Swine's volume of sperm

225-400

Horse's volume of sperm

60-100

Breeding soundness exam (BSE)

Fertility, body condition score, feet

Overall functions for the female reproductive tract

Control activity of organs (hormonal), transport sperm, produce oocyte, facilitate fertilization, provide environment for embryo and fetus, give birth to fetus, recycle to become pregnant again, provide nutrients to young

Vulva

passageway for urine, receptor for penis during copulation, passageway for fetus

Vestibule

Common duct for urine and reproduction, stimulates male for copulation, passage for fetus during parturition

Vagina

female organ of copulation at mating, birth canal at parturition, mucosal surface that changes during estrous cycle, copulatory organ, birth canal

Cervix

Thick wall extension of the uterus, structure is directly correlated to male penis, first sperm barrier in cow and ewe, transport sperm

Stallion ejaculation

Glans penis bells out and expands cervix, force of ejaculation sends semen directly into uterus

Boar penis

corkscrew shape, glans penis locks into the interdigitating pads of cervix

Functions of the cervix

barrier to sperm, reservoir for sperm, blocking bacterial invasion during pregnancy, birth canal

Uterus

incubator for fertilized ovum, aids travel of sperm, secretory organ, has two horns or branches

horns, body

Components of the uterus

Functions of the uterus

Transport sperm, muscle contractions, sperm motility, absorption and phagocytosis, partially prepares sperm for fertilization, provides environment for embryo, supports development of fetus, at birth expels fetus, recovers from pregnancy

Prostaglandin PGF2a

Hormone produced when not pregnant (by uterus)

Interferon tau

What signal is given off when pregnant?

Oviduct

Open-ended tube from area of ovary to uterus, passageway for sperm and ovum, site of fertilization, takes 3-5 days for ovum to travel down uterus

Oviductal functions

Transport sperm to site of fertilization, reduce sperm numbers to prevent polyspermy, remove oocyte from surface of ovary, transport oocyte to site of fertilization

Broad ligament

suspensory support for repro tract

Infundibulum

Catches ovum after ovulation, "catcher's mit"

Ovary

Produces female gamete, produces female sex hormones (estrogen & progesterone)

Cortex

Part of ovary that contains female germ cells, oocytes, follicles, corpora lutea (pl)

Medulla

Part of ovary that contains connective tissue, blood vessels, lymphatics, and nerves

Graffian

Mature follicle

Artretic

Deteriorated follicle

Corpus Hemorrhagicum (CH)

Ovarian structure, contains blood, lymph and granulosa cells, occurs before CL and CA

Corpus luteum (CL)

Ovarian structure, "yellow body" forms after ovulation, produces progesterone

Functions of progesterone

1. inhibits estrus and parturition

2. blocks myometrial contractions

3. stimulates endometrial secretion of nutrients

4. stimulates the production of a luteolytic agent to kill the CL if no embryo is present. Prostaglandin F2a

Corpus Albicans (CA)

Ovarian structure, white body, regressed corpus luteum, caused by prostaglandin

Luteinizing hormone (LH)

Secreted by: anterior pituitary

Acts upon: ovary

-Induces ovulation and development of the Corpus Luteum

Follicle stimulating hormone (FSH)

Secreted by: anterior pituitary

Acts upon: ovary

-Induces follicular development

Inhibin

Secreted by: Follicle

Acts upon: Anterior pituitary

-Causes reduction in FSH production

Estrogen

Secreted by: follicle

-Responsible for estrus, early stage development of the mammary gland

Progesterone

Secreted by: Corpus Luteum

"Hormone of pregnancy"

Oxytocin

Secreted by: Posterior pituitary, corpus luteum

Acts upon: smooth muscle

-Causes contractions of the small muscle fibers

Prostaglandin

Secreted by: Uterine lining

Acts upon: corpus luteum

-Causes the regression of the corpus luteum

Interferon tau

Produced by: fertilized ovum

Received by: uterus

-Pregnancy recognition signal

Why synchronize estrus?

Scheduled calving, more heats per season, problem cows are identified, early conception, increased heifer management, facilitates the use of A.I.

What does estrus synchronization help with?

Management, feed resources, facilities, uniform product, utilize labor

Ram effect

natural synchronization method

Flehmen response

Exterior response by male that tells when females are in estrus

Prostaglandins (in estrous synchronization)

cause leutolysis- shorten the current estrous cycle starting every animal at the same stage

Progestins (in estrous synchronization)

Keeps all animals at the same state until __________ are removed and they cycle together

Progesterone / Prostaglandin

_________________ is timing specific while _________________ is used as a management tool

Lutalyse

Common prostaglandin

PGF2a

What form of prostaglandin is used?

CIDR (controlled intervaginal drug release)

Progesterone insert commonly used to synchronize estrus in herds

-removed 7 days after insertion, cattle will show heat 24-48 hours after removal

MGA (melengasterol acetate)

Progesterone feed additive developed to suppress heat in feedlot heifers

Common signs of estrus

-Stands to be mounted by other animals

-Persistent trailing of other animals

-licking other animals

-Nervous and restless behavior

-red and swollen vulva

-mounting other animals

-clear mucus discharge

paint stick, gomer bull

Most common estrus detection aids

Artificial insemination

Placing semen into the reproductive tract of the female by artificial techniques rather than natural mating

Cow

What animal is artificially inseminated rectocervically?

-AM/PM rule

AM/PM rule

Universally accepted time for insemination of cows

Sow

What animal is artificially inseminated cervically?

Mare

What animal is artificially inseminated vaginocervially?

Sheep, goats, deer

What animal is artificially inseminated laparoscopically?

Goat

What animal is artificially inseminated with a speculum?

100%

What percent of poultry must be artificially inseminated?

Electro ejaculation

AI sperm collection method that stimulates nerve over bulbourethral gland

Extender solution

Components:

-Fructose- energy source

-Double distilled water

-Antibiotics

-Glycerol

-Egg yolk

Parturition

Action of giving birth, marks termination of pregnancy

Causes of dystocia

-Females are too young

-Abnormal presentations

-Abnormally small pelvis in female

-Fetus too large

AI Advantages

-Genetic improvement

-Disease control

-Improved record keeping

-Eliminates need for keeping bulls

AI Disadvantages

-Time required to detect estrus

-Percent of cows in estrus during the breeding season

-Trained personnel required

-Overuse of inferior sires

Embryo transfer

Movement of the pre-implantation embryos from the reproductive tract of the genetic mother (donor) to the reproductive tract of the surrogate mother (recipient)

Genetic gain (ET)

-Improvement in livestock through selective breeding

-Production of improved strains of livestock

Steps in ET process

-Super-ovulation

-Insemination

-Synchronization of donors and recipients (TIMING)

Follicular rescue

Induction of follicular development in excess of the normal number

FSH

What hormone is used to induce super-ovulation?

12 hours post estrus - 2 units

24 hours post estrus - 1 unit

Timing and units of semen for donor to be breed with

True

T/F: Recipient females must have synchronous estrous cycles with the the donor to achieve pregnancy.

7

How many days post estrus should embryos be collected in the bovine?

Growth

Increase in body weight until maturity is reached; increase in animal tissue: muscle, fat, and bone

True Growth

Only growth that involves an increase in structural tissues, excludes fat as storage tissue

Maturity

State of being fully grown or developed

Chronological age

animals age in terms of units of time

Physiological age

stages (landmarks) of development as the animal grows from conception to maturity

Hyperplasia

an increase in the number of cells