Reproductive Technologies

Reproductive Technology

Any method of REPRODUCTION that is different from NATURAL methods

Artificial Insemination

Placing SPERM into the female reproductive tract by means other than natural mating.

EMBRYO transfers

The transfer of FERTILIZED egg(s) from a DONOR female to one or more RECIPIENT females

Cloning

The production of an exact GENETIC COPY of an organism

Hormones

A chemical released by a cell or a gland in one part of the body that sends out messages that affect cells in other parts of the organism.

Estrogen

the source of estrogen is the ovary and the placenta

Major effects: Female reproductive organ growth Female secondary sex characteristics

Mammary gland duct growth

Progesterone

the source of progesterone is the corpus luteum and the placenta

Major effects: Uterine growth Maintenance of pregnancy Alveoli growth in mammary gland

Testosterone

the source of testosterone is the testicles

Major effects: Libido -- sex drive Accessory sex gland development Males secondary sex characteristics Spermatogenesis

Signs of Estrus (HEAT) in a Cow

Major indications of Estrus

1. Standing to be ridden2. Riding others3. Nervousness; restlessness4. Clear, thin, wet sticky

mucous flowing from the vulva

Minor indications of Estrus

1. Dirt or mud on flanks or back

2. Hair standing up on tail head

3. Bellowing4. Holding up milk

The most important indication of estrus (heat) is standing to be ridden.

Signs of Estrus (Heat)

Must observe 2-4 times daily, 30-60 minutes each time, for effective heat detection

May also use chin-ball markers or kamar detectors. (Gomer Bulls, Androgenized cows)

Artificial Inseminationplacing sperm

into the female reproductive tract by means other than natural mating

Advantages of A.I.

Wider selection and use of outstanding sires Example - one bull if used for natural

reproduction could have 30-40 calves per year for 8-9 years = 240 - 360 calves; one bull used to A.I. Could produce over 100,000 calves.

Advantages of A.I.

Rapid Genetic and herd improvementRapid proof of the bull is available

(EPD’s, TPI’s, etc.)Can overcome physical barriers to

mating example - behavior or injuries

Danger of the bull is eliminated

Advantages of A.I.

Disease is reducedNew crosses can be tried

experimentally without purchasing a new sire

Improved herd management due to increased observation

Elimination of cost of purchasing and keeping a bull

Disadvantages of A.I.

Skilled technicians are requiredCloser supervision of female is

requiredMay have increase in inbreedingMay be subject to certain abusesCost of initiating program (equipment,

membership in breeding organizations, etc.)

Semen Collection

Massage (bull) Insert hand into rectum to massage the area or the prostate, seminal vesicles and cowpers gland. Causes sperm to pass through the urethra by gravity and drip from the prepuce

Semen Collection

Artificial vagina (AV) As male mounts the female, the sheath is grasped and the penis is directed into the artificial vagina for ejaculation

Semen Collection

Gloved hand method (boar) As boar mounts sow, gloved hand used to massage and strip fluid from prepuce. Glans penis is grasped and pulled to side of sow for collection

Semen Collection

Electroejaculation Electrode inserted into rectum to stimulate ejaculation; not widely used with boars or stallions

Synchronized Ovulation

the process of causing a herd of cows or heifers to come into estrus and ovulate at or near the same time

Methods of estrus synchronization

Prostoglandin F2a -- hormone which can be used to synchronize estrus

Brand Names -- Lutalyse, Esrumate, Bovilene, Synchro-Mate B

May use a 1 or 2 shot program to get all animals in estrus.

Melengestrol Acetate (MGA) -- feed additive that suppresses estrus -- followed by a shot of prostoglandin.

Time for insemination

Cows: Optimum time is 12-18 hours after the beginning of estrus

A.M./P.M. rule -- Cows detected in estrus in the morning are bred that evening

Cows detected in estrus in the evening are bred the next morning.

Time for insemination

Ewes: Optimum time is 15 hours after the onset of estrus AI in sheep is not common in the U.S. because it is not practical.

Sows: Optimum insemination time is 30 hours after the onset of estrus

Mares: Optimum insemination time is mid to late estrus.

Equipment used for AI(artificial insemination)

1. AI Gun2. Straw of semen3. Sheath protector4. O Ring5. Thaw Thermos6. Straw Cutter7. AI Sleeve8. Paper Towels

AI Equipment

Errors made in Artificial Insemination

Misplacement of insemination tube:1. Placing semen in bladder2. Placing semen posterior of Cervix3. Allowing contamination to occur4. Placing semen to far into uterine horn

Improper thawing of semen Too hot or too cold

Embryo Transfer

The transfer of a fertilized egg(s) from a donor female to one or more recipient females.

Advantages of Embryo Transfer

1. average female may only have 5-8 offspring in a lifetime; ET will increase that number.

2. Improve genetics rapidly3. the donor mother never

experiences pregnancy4. all the advantages of AI

Advantages of Embryo Transfer

5. Easier to import of species6. Increased marketing opportunities7. Embryos can be stored indefinitely

Embryo Transfer

Superovulation: The Drug induced ovulation of a more than normal number of eggs.

Synchronization: Donor and Recipient must be in same stage of estrous cycle for conception results.

Embryo Transfer

Condition: Only healthy cattle in good physical condition should be considered .

Insemination: Conducted shortly after detection of estrus and at 12-hour intervals for 3 inseminations. High quality semen is required.

Cloning

Cloning

Making an exact genetic copy of an animal.

Steps: 1. remove cells from donor (stop

cell division) 2. an unfertilized egg is remove

from recipient & nucleus is removed.

Cloning (Steps)

3. the donor cell and the empty egg cell are fused together.

4. the egg is then placed into a uterus of a female.

Cloning

http://www.youtube.com/watch?v=bbZiOiPVG6c

Pregnancy Testing

Three Types: 1. Rectal Palpation: inserting arm into

rectum 2. Ultra-sound: The use of ultrasonic

waves for diagnostic monitoring of a developing fetus.

3. Blood/urine test: analyzing of fluids for the hormonal detection.

Ultra-sound

Pregnancy Testing

Advantages for pregnancy checking: 1. know when complications arise.2. exacting the date of delivery3. find out if you have to re-breed