Reproduction

• genetics
• productivity
• disease soundness (brucellosis status)
• soundness

one bull per 30 cows.

(most beef breeds)

may be used to inseminate hundreds of cows

(most dairy breeds)

march-june

saclike portion of the male reproductive system that remains outside of the body, contains the testicles and epididymis

• skin
• tunica dartos
• tunica vaginalis

tissue that forms the pocket around the testicles once they have descended from the abdominal cavity

muscle tissue responsible for raising and lowering the testicles in response to temperature 

if one of both of the testicles do not descend and are held within the body cavity

(animal may also be called a ridgeling or ridgel)

sperm and testosterone producing organs of the male reproductive system

produce sperm cells

produce testosterone 

hormone responsible for masculine appearance 

long coiled tube connected to each of the testicles

epididymis

reabsorbed by the body

tube that carries urine from the bladder

(in the male semen is also moved through here)

• sperm cells
• other fluids excreted from accessory glands

• seminal vesicles
• prostate gland
• Cowper's glands

• open out into the urethra
• produce a fluid that transports and protects the sperm

• located near urethra and bladder
• produces a fluid that is mixed with seminal fluid

produce a fluid that travels down the urethra ahead of the seminal fluid to help clean and neutralize the urethra, protecting the sperm as it travels

organ that deposits the semen into the reproductive tract of the female

spongy tissue that surrounds the urethra and fills with blood when the male is aroused causing the erection necessary for copulation

extends the penis from the sheath

(in bulls, rams, boars)

helps to bring the penis back inside the sheath after copulation

• artificial vagina (sperm catcher on end)
• electroejaculator (rectal probe)

• macroscopic- color, volume, consistency
• microscopically- motility, morphology, concentration

• estrogen
• progesterone 

eggs or ova

ovaries

external folds of vulva

internal folds of vuvla

sensory and erectile organ of female

period of time that the female is receptive to the male for breeding

• standing when mounted by another cow
• nervousness
• swelling of the vulva
• inflamed appearance around lips of vulva
• frequent urination
• mucus discharge from vulva
• trying to mount other cattle

corpus luteum

hormone of pregnancy

• fertilized egg implanted on uterus
• other eggs stopped from forming
• pregnant condition is maintained
• mammary glands begin to develop

union of the sperm and egg

24-30 hours in the female reproductive tract

(egg cell 12 hours)

time during which the animal is pregnant

(285 days; around 9 months)

• transport of oxygen and nutrients to the fetus
• removing wastes from the fetus

near the end of gestation, the corpus luteum begins to reduce and produce less progesterone and thus..

leads to increase of estrogen in body which causes uterine muscles to contract, beginning the process of birth.

2-6 hrs

• water breaks
• second water bag containing fetus breaks
• fetus emerges forelimbs and nose first

30 min-4 hrs

afterbirth is expelled

8-12 hours

• dystocia
• first calf heifer
• disproportionate bull/cow size ratio
• brucellosis status
• caesarean section

• obstetrical chains/ropes
• obstetrical forceps
• hercules fetal extractor

• uterine infections
• cysts on reproductive organs
• cryptorchidism (in male)
• uterine prolapse