Biotechnology In Livestock Production
(Unit 11)
A. Definition
1. The science of altering genetic and reproductive processes in
plants and animals.
B. Two major areas of biotechnology
1. Genetic Engineering
2. Embryo Transfer
C. Genetic engineering
1. Is based on a technology involving Recombinant DNA
(Deoxyribonucleic acid)
2. Involves taking a tiny bit of DNA containing the desired gene
from one organism and splicing it into the DNA strand of another
organism.
3. Purpose
 To have the recipient organism take on the characteristic
controlled by the transferred gene.
4. Examples:
a. Disease resistant animals
b. Growth regulators
c. New drugs and vaccines
d. Specify size and sex of animals
e. Organism that “eats” oil
D. Bovine Somatotropin (BST)
1. Somatotropins are proteins that affect the utilization of energy
in the body.
2. Causes energy derived from feed to be used for milk production
rather than weight gain.
3. Does not reduce energy available for body maintenance.
4. Increases energy available by improving breakdown of fat and
increasing appetite.
5. Small amounts of BST are produced naturally in the cow by the
pituitary gland.
6. Previously, the only source of BST for research has been from
pituitary glands of dead cows.
7. Now, because of genetic engineering, large quantities of BST
can be produced.
8. Gene that controls BST production is spliced into the DNA of a
bacteria (“Agrobacteria” ) and is injected into a cow causing
increased BST production.
9. Research at the University of Wisconsin – Madison and Cornell
University in New York has showed an average increase of 40%
over the lactation (305 days).
 20,000# X 40% = 8000# of extra milk
 8000# @ $10/cwt = Gross Return of $800 per cow
E. Porcine Somatotropin (PST)
1. Is produced naturally by the pituitary gland of the pig (*it acts
as a growth regulator). Production decreases as an animal
matures.
2. Produced through RDNA technology
3. How it works:
a. Causes an increase in cell division in muscle tissue
b. Causes a decrease in fat storage and increase in
accumulation of protein
c. Improves feed efficiency and decreases fat deposition
4. Results:
a. Increases feed efficiency 29%
b. Increases daily gain 19%
c. Increases loin eye area 12%
d. Decreases fat 33%
5. Must be injected daily
F. Opposition to “Biotech”
 People fear:
1. The production of a “new” uncontrollable disease
2. Freak animals
3. Long-term adverse effects on the environment from the use of
such products
G. Biotech in Crop & Food Production
1. Lowered costs and increased yields
2. Improved feeding values
3. New corn plant
a. Produces higher levels of tryptophan (an amino acid
essential for protein formation in an animals body)
b. This was the first plant patented
4. Other plant research areas:
a. Herbicide resistance (Roundup Ready, etc.)
b. Pest resistance (BT, etc.)
c. Frost resistance
d. Salt tolerant
e. Improved N-fixing ability
f. Drought resistance
g. Pharmaceuticals
H. Embryo Transfer
1. Well established in cattle industry, especially dairy
2. Process:
a. Cow is treated with hormones to cause “superovulation”
(can produce as many as 25 eggs)
b. “Donor” cow is then artificially inseminated
c. During this process, “Recipient” cows or heifers are treated
with hormones to synchronize their heat cycle to be the same
as the donor cow.
d. After the eggs are fertilized and before they leave the
oviduct, the cow is “flushed” with a saline solution or a
solution of egg yolk and D.M.S.O.
e. Ovaries and oviducts are massaged & flushed with fluid –
which washes the fertilized eggs out of the body and into a
cylinder.
f. Individual embryos are located under a microscope and put
into a straw.
g. Embryo may then be implanted into the uterus of a recipient
animal (use A.I. methods)
3. Embryo transfer makes it possible to get many more offspring
out of the same genetic match.
4. Embryos may also be frozen much the same as cattle semen
samples.
 First research in the U.S. was done in central Wisconsin in
1982. This process is now widely used.
5. Most transfer work is done non-surgically with success rates of
approximately 75%
I. Cloning
 Research has also successfully split embryos resulting in as
many as 5 identical calves.
 Ethical issue – Should cloning of animals be allowed?
J. Slower progress in Animal Biotechnology
1. Many characteristics are controlled by multiple genes instead of a
single gene.
2. Lack of money for research
3. Government regulations
4. Environmental groups filing lawsuits to stop research and testing
5. Many farmers don’t support genetic engineering because they feel
we already have surplus production
K.