Animal Reproduction-By: Dr. Dhiren Bhoi

Animal Reproduction

Conditions for Fertilization

Anatomy of Male & Female must be Anatomy of Male & Female must be compatiblecompatible

Female must be in HeatFemale must be in Heat Egg must be matureEgg must be mature

What is the function of the Male?

produce large numbers of live sex produce large numbers of live sex cells/gametescells/gametes

(spermatozoa)(spermatozoa) contribute 1/2 chromosomescontribute 1/2 chromosomes

What are the Male Reproductive Organs?

TesticlesTesticles - produce spermatozoa & male hormone - produce spermatozoa & male hormone TestosteroneTestosterone

ScrotomScrotom - sack which carries testicles - sack which carries testicles– functions as a heat regulatorfunctions as a heat regulator

MonorchidMonorchid - one fertile testicle - one fertile testicle CryptorchidCryptorchid - both testes remain in body cavity (sterile) - both testes remain in body cavity (sterile) CastrationCastration - removal of testicles - removal of testicles

– lack sex drive (libido)lack sex drive (libido)

– gain weight quickergain weight quicker

What are the Male Reproductive Organs?

EpididymisEpididymis - tube connects to testes - tube connects to testes– storage of spermatozoa (200 billion at a time)storage of spermatozoa (200 billion at a time)– spermatozoa mature as they migrate throughspermatozoa mature as they migrate through

Vas DeferensVas Deferens - tube connects to - tube connects to epididymusepididymus– if removed, can't reproduce = vasectomyif removed, can't reproduce = vasectomy

What are the Male Reproductive Organs?

UrethraUrethra - begins at bladder and continues - begins at bladder and continues through penisthrough penis

Sigmoid FlexureSigmoid Flexure - "S" shape in urethra - "S" shape in urethra allows for extension of penis outside of allows for extension of penis outside of body for reproductionbody for reproduction

Male Accessory Sex Glands

ProstateProstate 2 Seminal Vesicles2 Seminal Vesicles 2 Cowper’s glands2 Cowper’s glands

What is the function of the Accessory Sex Glands?

provide medium for transporting spermprovide medium for transporting sperm adds volumeadds volume provides nutrientsprovides nutrients cleans & flushes urinary tractcleans & flushes urinary tract

Artificial Insemination

•Required Equipment

•A.I. Rod

•Semen Straw

•Lube

•Genetic Diversity

•Select the bulls you want to use based on EPDs

•Compared to Natural Mating

Artificial Insemination vs.. Natural Mating

ProsPros

- More Genetic Diversity

- Don’t Have To Maintain A Bull

- More Controlled Breeding Season

- More Cost Effective

- More Hygienic

- Easier To Determine Calving Date

ConsCons

- More Equipment Required

- Heat Watch Required

- Experienced A.I. Technician

- More Labor Intensive

- More Time Consuming

Take out a Piece of Paper

QuizQuiz– 1. What are the main structures of the Male Reproductive Tract?1. What are the main structures of the Male Reproductive Tract?

» List at least 4List at least 4

– 2. What are the advantages of Artificial Insemination?2. What are the advantages of Artificial Insemination?

» List at least 3List at least 3

What is the function of the female?

contribute 1/2 chromosomescontribute 1/2 chromosomes care for young in uterus and after birth until care for young in uterus and after birth until

weaningweaning

What are the Female Reproductive Organs?

VulvaVulva - exterior portion of reproductive - exterior portion of reproductive tracttract– provides visual signs of heatprovides visual signs of heat

VaginaVagina - between vulva & cervix - between vulva & cervix– Cows & Ewes: semen is deposited hereCows & Ewes: semen is deposited here– Mares & Sows: semen is deposited in the Mares & Sows: semen is deposited in the

cervixcervix

What are the Female Reproductive Organs?

CervixCervix - "Mouth of the womb" - "Mouth of the womb"– opening into uterusopening into uterus– at birth cervix stretches to allow baby to passat birth cervix stretches to allow baby to pass– during pregnancy cervix becomes blocked with during pregnancy cervix becomes blocked with

a mucous plug to prevent infectiona mucous plug to prevent infection

What are the Female Reproductive Organs?

Uterine HornsUterine Horns - two branches of uterus- two branches of uterus Fallopian TubeFallopian Tube - uterine horn becomes a - uterine horn becomes a

small tubesmall tube– Site of fertilizationSite of fertilization– lined with cilia which aid in egg migrationlined with cilia which aid in egg migration

Ovaries

located at end of fallopian tubeslocated at end of fallopian tubes possesses large number of eggs in all stages of possesses large number of eggs in all stages of

developmentdevelopment this is all the eggs she will ever have, unlike the this is all the eggs she will ever have, unlike the

malemale very few eggs reach maturityvery few eggs reach maturity if not fertilized, the egg is reabsorbed by the bodyif not fertilized, the egg is reabsorbed by the body

Reproduction in Males

After sexual maturity, sperm production is After sexual maturity, sperm production is continuouscontinuous

TestosteroneTestosterone is responsible for: is responsible for:– growth, development & activity of accessory growth, development & activity of accessory

glandsglands– survival of spermatozoasurvival of spermatozoa– secondary sex characteristics:male voice, sex secondary sex characteristics:male voice, sex

drivedrive

Reproduction in Males

SemenSemen - collective term for all fluid - collective term for all fluid ejaculatedejaculated

sperm and fluid from accessory glandssperm and fluid from accessory glands

Reproduction in Females

Farm animals reach sexual maturity at 4 Farm animals reach sexual maturity at 4 months (sow) to 24 months (mare), thenmonths (sow) to 24 months (mare), then

Female comes in heat (estrus)Female comes in heat (estrus) Egg released by ovaryEgg released by ovary Egg travels down tube until fertilized by Egg travels down tube until fertilized by

spermsperm EstrogenEstrogen - female hormone which regulates - female hormone which regulates

estrusestrus

What does "in heat" mean?

Heat is the time when a female is receptive Heat is the time when a female is receptive to the male and will allow breeding to take to the male and will allow breeding to take placeplace

Heat is actually divided into 4 phases of the Heat is actually divided into 4 phases of the cycle.cycle.

Estrous Cycle:

Proestrus:Proestrus: ovary is about to release an egg ovary is about to release an egg Estrus:Estrus: female receptivity female receptivity Metestrus:Metestrus: uterus prepares for pregnancy uterus prepares for pregnancy

fertilized egg attaches to uterusfertilized egg attaches to uterus Diestrus:Diestrus: longest period of cycle longest period of cycle

– inactiveinactive Estrous Cycles stop after conception, and Estrous Cycles stop after conception, and

begin soon after Parturition (birth)begin soon after Parturition (birth)

Females also show external signs of "Heat"

aggressive behavioraggressive behavior swelling and/or color change of vulvaswelling and/or color change of vulva

A Mature Male is called a:A Mature Male is called a: BullBull A Mature Female is called a:A Mature Female is called a:

CowCow The act of Giving Birth is called:The act of Giving Birth is called:

CalvingCalving A Castrated Male is called a:A Castrated Male is called a: SteerSteer An Immature Female is called a:An Immature Female is called a: HeiferHeifer

Beef (Bovine) Terms

What do you call a mature male hog?What do you call a mature male hog? BoarBoar

What do you call a mature female hog?What do you call a mature female hog?

SowSow

What do you call the act of giving birth?What do you call the act of giving birth?

FarrowingFarrowing

What do you call a castrated male hog? What do you call a castrated male hog? BarrowBarrow

What do you call an young female hog?What do you call an young female hog?

GiltGilt

Pig (Porcine) Terms

What do you call a mature male?What do you call a mature male?

RoosterRooster

What do you call a mature female?What do you call a mature female?

HenHen

What do you call a young female?What do you call a young female?

PulletPullet

What do you call a castrated male?What do you call a castrated male? CaponCapon

Poultry (Ovine) Terms

What do you call a mature male horse?What do you call a mature male horse?

StallionStallion

What do you call a mature female horse?What do you call a mature female horse?

MareMare

What do you call a castrated male horse?What do you call a castrated male horse? GeldingGelding

What do you call a young horse?What do you call a young horse?

Foal or ColtFoal or Colt

What do you call an immature female horse?What do you call an immature female horse?

FillyFilly

What do you call the act of giving birth for horses?What do you call the act of giving birth for horses? FoalingFoaling

Horse (Equine) Terms

Any questions?