Bovine Spongiform Encephalopathy:
“Mad Cow Disease”
URBS 515 Race Poverty and the Environment
Professor Raquel Pinderhughes
Urban Studies & Environmental Studies Programs
San Francisco State University
Public has permission to use the Material herein, but only if author(s), course, university and professor are
This presentation focuses on the history and impacts of
Bovine Spongiform Encephalopathy (BSE).
• It is designed to inform the public about the
danger of this disregarded disease in the United
• It analyzes and describes the origins and
transmission of this disease, paying particular
attention to the social, environmental and public
health impacts associated with BSE.
• We start by analyzing the rendering process that
is thought to be a major factor in transmission of
this disease. We then look at a brief history of it‟s
effect on humans and other animals. This is
followed by a comparison of the safeguards
taken by the U.S. compared to other countries.
• We conclude with proposals to protect those who
consume beef products from the United States.
Why is it important for us as Americans to know about a disease
that is thought to be a problem only in Europe, and more
recently, in Canada?
Almost 77 million Americans eat beef every day. 1
If the research is true that humans are susceptible to the human
form of Spongiform Encephalopathy, and this disease is in fact
transmissible from consuming infected beef products, why isn‟t
more being done to protect the American public?
• BSE can be transmitted from mother to fetus, as well as from bull
sperm to the female.
• Also contracted when infectious agent (prion) is ingested in food.
Adult cows are fed rendered animal protein to aid in
• Calves are fed a “baby formula” made from bovine blood because it it
much less expensive than milk, not to mention the comparative resale
values of the two liquids.
“Protein Concentrates”: rendered
animal protein feed
• This inexpensive, high protein food is sold as
granules or dry food pellets to animal farmers for
vigorous animal growth.
• It is sold in greatest quantities to cattle farmers
because administration of hormones such as
RGBH to their cows for increased milk production
requires them to increase the cow‟s protein
• This feed is also given to:
– Turkeys, chicken and ducks
– Catfish, salmon and shrimp
– Domestic animals (cats and dogs)
– Zoo animals
Rendered Protein Ingredients:
Animals unfit for human
consumption such as:
– Sick cows
– Sick pigs
– Sick turkeys, chicken and
– Sick catfish, salmon and
– Cats and dogs
– Zoo animals
– Road kill
– Frying oil from restaurants
– Brains, spinal cords, feathers,
hooves, skins, hair, fur,
whiskers, bones, teeth, etc.
– Sewage sludge
– Sawdust/wood scraps
– Cement dust
– Maggot infested grains
Rendering Process: Health and
The animals and other
ingredients are processed into
smaller pieces in a “Double
Screw Press” (top left) and then
boiled down in huge vats (bottom
left) at extremely high
temperatures with dangerous
chemicals. “Infected tissue from a
single animal has the potential to
mingle with tissues from
thousands of others, and then be
distributed widely in feed.”1
Worker Hazardous Exposures
• Dangerous chemicals such as hydrogen sulfate, potassium permanganate,
chlorine gas, sodium hypochlorite, lime, formaldehyde, lye, acetic acid and
• Extreme Heat
– When heat of process was lowered in response to worker safety issues,
process does not sufficiently remove contaminants: Salmonella, E. coli,
infectious prions pesticides, pharmaceuticals and hormones. These
contaminants not only pose a problem for the animals ingesting the food
but also for the workers handling the product.
• Aerosolized fat mist that sprays out of the vats coats the walls and floor of
the plant, making all surrounding surfaces very slippery and creating an
extreme fire danger.
The rendering industry defends their work as a form of
• 1.3 million tons in the U.K. in 19881
• 15 million tons in the U.S. in 19922
This is waste that would have otherwise gone into
landfill. But is the risk belong taken worth the
1. (Rhodes, 176) 2. (Rampton, 63) 10
Not only is this rendered
protein used in the food
we feed our pets and food
animals, it is in the
products we use
everyday. The fat is
skimmed off of the top of
the vat during the
rendering process and
used to make
cereal bars, … lipstick
and hand lotion and
garden fertilizers, tires
and yogurt and breath
Therefore, not only have we turned herbivore cows into not just carnivores but
cannibals, we have put ourselves and other animals at risk . The old adage “you are
what you eat” has never been more true-not only are we the food that we eat, we are
also what our food consumes. Humans, being at the top of the food chain, are
consuming all of the toxins, chemicals, hormones and diseases that affected our food
before we consumed them.
Symptoms of Bovine Spongiform
loss of motor function
loss of appetite
the initial discoveries of BSE…
• In April of 1985, the first identified case of BSE was initially believed to be “grass
staggers,” a common illness caused by Magnesium deficiency. The cow was
observed as seeming to hallucinate.1 Given an “Unknown” diagnosis, as a possible
brain tumor or lead poisoning. The brain autopsy revealed spongiform patterns.
• On March 20, 1996 the UK Department of Health announced that BSE was in fact
transmissible to humans.
• The announcement was so devastating to the UK cattle economy that many
ranchers were forced into bankruptcy beacuse of the immediate loss of entire herds
of potentially contaminated cattle, as well as the immediate consumer boycott of beef
and beef products. This downturn was so terrible in fact that there was an epidemic
of suicides within the ranching community.2
• School districts began banning beef in school lunches and vegetarianism rose in
popularity for the general public in the UK.
• In June, 1987 John Wilesmith, a veterinarian epidemiologist for the Ministry of
Agriculture, Fishers and Food (MAFF) made the link between BSE and cattle feed
made from scrapie infected sheep.3
• On July 7, 1988, a settlement was
offered by British Agriculture of
payment for 50% of the worth of the
cow if reported to the government.
• This in fact gave the ranchers an
incentive not to report suspicious
cases, as they would make the full
profit from sneaking past inspection
and selling the meat into the market
versus reporting the problem and
only receiving 50% compensation.
• Not only did ranches lose money
from BSE reports, they lost
credibility as well as their customer
base, and in effect became
The effect of BSE in the E.U.
Millions of suspect
animals in the UK and
across Europe have been
destroyed since 1986, but
the disease is still very
Causative agent of BSE: What is
• Identified by Dr. Stanley Prusiner, who in 1997 won
the Nobel Prize for his research on prions.
• Does not contain RNA or DNA (therefore not
technically alive like other infectious agents like
viruses or bacteria)
• Does not evoke any detectable immune response or
inflammatory reaction in host animals.
• In most animals, 3-7 years dormant incubation where
the animal is asymptomatic.
• Average age of cows in the U.S. is 4 years old,
meaning that the animal may be infected but still
asymptomatic at time of slaughter.
Prions in the body
Found in mainly in the brain, spinal cord and nervous tissue, with
increasing research discovering prions in glands and blood as well.
Physical Attributes of the affected brain:
– Enlarged astrocytes- Star shaped cells
attached to blood vessels in brain.
– Holes where neurons used to be.
– Amyloid Plaques-flower shaped protein
Scrapie Brain 19
Prion protein is indestructible
by heat up to 1000° F (350° C)
Hot enough to melt lead.
In 1986, 4.5 million cows were incinerated in the U.K. after the
discovery of BSE. The ashes, stored in underground concrete
containers, were retested again in 1998 and found to still be
infected with active prions.
So how do these prions affect
Creutzfeldt-Jakob Disease (CJD)
New Variant Creutzfeldt-Jakob Disease (vCJD)
• Cannibal culture of Papua New Guinea.
• Affected mostly women and children, with
a small amount of men. anywhere from 5
to 10 percent of the population died each
year from kuru.1
• When loved one died, men ate muscle
portions and women and children were left
with the lesser organs and brain, where
we now know prions tend to cluster.
• The rare male cases occurred because of
the possible 20 to 30 year dormancy
period of prions where the infectious
agents were ingested as children.
• Analyzed by New Yorker Carleton
Gajdusek and Lithuanian Dr. Vincent
Zigas (both in photo) in 1957.
• Initially believed to be a virus causing
encephalitis (swelling of the brain), with
the same symptoms as Parkinson's,
Alzheimer's, and MS. However these
were degenerative, not infectious
diseases, and not epidemic as kuru was.
• After autopsy, Gajdusek made the
connection of brain damage to recently
• No treatment was ever found, and when
cannibalism was eventually phased out
of the culture, so too came the
disappearance of kuru.
Creutzfeldt-Jakob Disease (CJD)
• Discovered in 1921by Dr. Hans Gerhard
Creutzfeldt and Dr. Alfons Jakob,
colleagues at the University of Hamburg
• Now more common that rabies.
• Physical attributes of the affected brain:
– Enlarged astrocytes- Star shaped cells
attached to blood vessels in brain.
– Holes where neurons used to be.
– Amyloid Plaques-flower shaped protein
Microscope slide of brain
affected by CJD
(first 7 same as BSE)
• aggressiveness (biting and hitting).
• loss of motor function.
• loss of appetite.
• self mutilation.
• inability to swallow.
90% of deaths usually occur within one year of
diagnosis, difficult to confirm diagnosis until
• Humans can acquire the prion
by exposure to meat that has
come in contact with the brain
or spinal column of the
• Surgical equipment can be
unknowingly infected by use
on a patient with CJD, and
In common slaughtering practices, because sterilization
the animal is often sliced at least techniques do not kill the
once through the torso, severing the
spinal column and exposing all the prion, the are transmitted to
the surrounding flesh to the the other patients in
infectious agent. subsequent procedures.
Similarity to Alzheimer‟s disease
• very similar patterns of dementia.
• because of late onset of CJD, both usually occur later in life.
• CJD often misdiagnosed as the more common Alzheimer‟s, as only way to
differentiate is post mortem brain autopsy (which most families do not agree
• However, a 1989 article in the journal Neurology explains that autopsies of 54
dementia patients at the Veterans Medical Center in Pittsburgh, PA revealed
that 3 of the had actually died of CJD. Given this figure we can infer than as
many as 5% of Alzheimer‟s patients are actually suffering from CJD.
• In Georgia, according to state law, autopsies cannot be performed on
suspected CJD cases because the equipment cannot be sterilized.
As with all TSE’s there is no cure or proven treatment.
New Variant CJD (vCJD)
• Much earlier onset but same
symptoms as classic CJD, often
with prolonged life expectancy.
• A recent test on surgical
equipment used for tonsillectomies
in the U.K. revealed that 50% of
tools were infected with vCJD,
even after sterilization and
Jonathan was diagnosed with vCJD
autoclaving. (The tonsils are one of at 17 and treated with the drug
Pentosan polysulphate (PPS) ,
the major glands where the body commonly used as an arthritis
stores prions.) treatment for dogs. This extended
his life by several years, but did not
Other Forms of Transmissible
• Known to have existed for at
least 200 years without being
transmitted to humans, while
being endemic in sheep
populations all over the world.
• There are 23 variations of prion
mutation possible, each with a
different incubation period as
well as patterns of amyloid
plaque in the brain.
• Each variation is known by a
unique symptom, such as
“drowsy”, “hyper”, or “fat
Domestic and Exotic Felines
• The first case of domestic Feline Spongiform Encephalopathy
was discovered in the U.K. in May of 1990. Max was a 5 year
old Siamese cat. The FSE was discovered in a rare autopsy
(which are thought to be too costly and unnecessary by most
• Lab tested cats are not susceptible to scrapie but extremely
susceptible to BSE. These results reinforced the findings that it
was possible for a species (such as humans) to be susceptible
to BSE without being susceptible to scrapie, despite their
A Puma and 3
cheetahs died from
FSE in 1989 at the
London Zoo from
Other Zoo Animals
Arabian Oryx Gemsbok
From 1986 to 1989. The London Zoo lost several varieties of
hoofed ruminants (cud chewing animals), including Nyala,
Gemsbok, Kudu, Eland and Arabian Oryx, (all similar to antelope
or deer), to spongiform encephalopathy. These animals had all
been fed rendered protein. 32
• Wisconsin is the largest U.S.
producer of mink.
• Known as sentinel species, mink
often show disease before other
animals because they are fed stock
animals unfit for human
consumption from slaughterhouses
• Contract many bovine diseases-
anthrax, botulism, tuberculosis.
• Outbreaks of MSE common,
devastating to ranchers. “ a single
outbreak could wipe out all of the
animals on an entire mink ranch.”1
100% fatal to mink exposed to
contaminated feed. Ranched for their fur, these carnivorous
• Isolated prion from autopsy animals are extremely susceptible to Mink
indistinguishable from scrapie. Spongiform Encephalopathy from eating
other infected animals.
Chronic Wasting Disease
(Deer and Elk)
• Chronic Wasting Disease is the
most similar to scrapie.
• The infected animals exhibit
more progressive degeneration
(similar to Alzheimer's) than
• Most likely not contracted by
ingesting infected proteins, but
through everyday contact with
other infected animals in their
• In laboratory tests, animals were
injected with active prions from cows
infected with BSE.
• The infectious agent was not
ingested in food as most animals and
humans would be exposed to the
prions. Even so, all of the test
subjects contracted some form of
– sheep (different variation of
– mice/ rats
But we‟ve only had one confirmed
case of mad cow disease in the
U.S. ! How can we blame BSE for
all of these other spongiform
encephalopathies occurring in the
U.S., especially vCJD?
“The Cow that Stole Christmas.”
• On December 23, 2003, the first confirmed case of BSE was reported
on a family farm in Moses Lake, Washington .
• Initially described by federal officials as a “downer cow” the family later
came out that the cow was in fact ambulatory, and that the test was run
not because the animal was sick but because the family farm has a
“special contract with the government to collect brain samples from up
to 1000 animals for mad cow testing, no matter what their physical
Since the animal was healthy, the program that was begun after this
discovery by the USDA does not fully address the problem, as it
only allows random testing on “Downer Cows”.
The U.S. Beef Market: At Home
• US local beef market not
significantly hurt by
discovery of BSE.
• There was a slight decline in
U.S. sales in January and
February of 2004. However,
in many places sales of beef,
both at retail and wholesale
dealers, are reported to have
increased from the previous
years due to consumer trust
in government protection.1
The U.S. Beef Market:
Beef is The United State’s #1 export:
• Any damage to this international economy would have widespread
impacts across the country.
• Because more than 30 nations have now banned beef from the United
States, Many packing plants are laying off workers and feedlots left with
thousands of unsold animals. Those that do sell are at such a low price
that “some feeders feel... lucky if the broke even on each animal sold.”1
Sales of approximately 9.6 percent of total U.S. production, or 3.1
billion pounds of beef will be lost if confidence is not regained.
“Government officials have placed concerns for the food
industry over human health and welfare.” 1
Does this result in a lack of regulation?
• In the U.S. more than 1.8 million cattle collapse before slaughter yet
are still seen as “fit for consumption”. About 100, 000 of these “die
mysteriously of what is known as Downer Cow Syndrome” but are not
tested and are still consumed by humans.2
• only one out of every 18, 000 cows slaughtered for human consumption
are tested for BSE in the United States. (.000055%)
• The USDA must authorize every test. When a cattle farmer proposed to
voluntarily test every cow, their request was denied and the practice was
forbidden across the country. 3
What information do these countries have that is being kept
from the American public? Do Americans not deserve the
same protection given citizens all over the industrialized
“It‟s unlikely the single Holstein
discovered in Washington state is the
only sick animal ever imported into
the country from Canada, and
possibly Europe... Since none of the
other animals was (sic) detected, their
infected tissues were almost certainly
processed into cattle feed years ago,
spreading and amplifying the disease
„so that cattle in the U.S.A. have also
been indigenously infected‟.”- USDA
Report submitted to Ann Veneman,
Secretary of Agriculture.1
So why do we continue with these
• In an effort to contain the problem, in addition to testing,
many public interest groups have proposed banning feeding
animal protein to animals.
• 1997 USDA “advisory” barring ruminant (cud chewing
animal) protein from cattle feed seen as more as a
suggestion than enforceable. (It is still legal to feed to all
other animals, however.)
• The Vice President of the American Feed Industry
Association, Richard Sellers estimates loss of $100
million annually “if a ban was imposed on feeding
animal protein to cattle.”1
Who is more important to the U.S. government,
their people or their businesses?
The American public trusts the Federal
government to protect us, as a parent
would protect their children. As our
parent, would they take the risk of
feeding us something that they know has
a very good chance of making us sick?
No parent would ever willingly put their
child in danger.
So too should the USDA, FDA, CDC and
DHHS care for us.
Recommendations to USDA
and FDA to more adequately
protect consumers :
(Compiled from suggestions by Physicians
Committee For Responsible Medicine, Public
Citizen and the World Health Organization)
1. Restrict marketing of downer cows for any purpose, whether for animal or human
2. Create strict regulations for cattle feed that match those of the E.U. nations and
Japan. “ We need to remember that cows are not meant to eat cows or other
animals.” Sue Jarrett, Colorado rancher. 1
3. Properly train and equip field personnel to test and report possible cases in a timely
and effective manner.
4. Properly label potentially contaminated food, (including those product with animal
byproducts such as gelatin or “natural flavorings”) with stickers similar to salmonella
warnings on chicken and Surgeon General warnings on tobacco products.
5. Prohibit the use of animal byproducts in cosmetics and medications.
6. Increase communication within regulating agencies to expedite action if necessary.
Research is performed by National Institutes of Health (NIH), Protection primarily the
issue of the FDA, Human disease surveyed by the Center for Disease Control (CDC)
and all of these agencies are overseen by the Department of Health and Human
Services (DHHS). Better communication will mean faster response times.
“If you don‟t look for it,
you‟re not going to find it”
- Howard Lyman, former
Montana cattle rancher.
Animal and Plant Health Inspection Service (APHIS)-USDA
Program Aid No. 1705 Bovine Spongiform Encephalopathy: An Overview. October, 2001
Veterinary Services February 2002 Bovine Spongiform Encephalopathy Fact sheet
Bovine Spongiform Encephalopathy (BSE) Response Plan Summary
Barone, John. “U.S. mad cow discovery lowers int'l. beef exports, prices.” Nation's Restaurant News, February 2,2004, Vol. 38 Issue 5, p36.
“BSE Experts say Old Meat „Is Safe‟” February 4 2004
“vCJD and BSE - the link” October 20, 2000
“CJD Drug Hope” September 25, 2003
The Caledonian Cat Clinic http://www.catclinic.co.uk/health/fse.htm
Center For Disease Control (CDC) http://www.cdc.gov/ncidod/diseases/cjd/cjd_fact_sheet.htm
Doughton, Sandi and Scott, Alwyn. “Experts predict more U.S. cases of mad cow.” Seattle Times Thursday, February 05, 2004
Department of Agriculture-Office of the Secretary
[Docket No. 04-001-1] “Declaration of Extraordinary Emergency Because of Bovine Spongiform Encephalopathy.”
Department for Environment Food and Rural Affairs http://www.defra.gov.uk/animalh/bse/bse-science/level-4-othertses.html
Duke University http://pathology.mc.duke.edu/neuropath/cnslecture2/cnslecture2.htm
Environmental Health News http://www.environmentalhealthnews.org/today/2003-12/2003-12madcow.htm
GAIN Report Global Agriculture Information Network
“European Union Livestock and Products European Commissioner David Byrne's BSE report March 2004”
Japan Grain and Feed Ministry of Agriculture, Forestry and Fisheries (MAFF) Press Release: “Ban on Use of Animal Protein Products or Feed and Fertilizers– As Well as
“European Union Livestock and Products Annual” 2001
“Indonesia Livestock and Products BSE Scare Provides Opportunity for U.S. Exports 2001”
Greeley Tribune. “Greeley, Colo.-Based Meatpacker Swift Reports Rise in Quarterly Sales.” April 6, 2004
Josephson, Julian. “Cows for Fear: Is BSE a Threat to Human Health?” Environmental Health Perspectives Volume 106, Number 3 March 1998
King, Anna. “Moses Lake, Wash., Meat Business Claims Mad Cow Case Came from Healthy Animal.” Tri-City Herald (Kennewick, WA), February 19, 2004
Klitzman, Robert, M.D. The Trembling Mountain: A Personal Account of Kuru, Cannibals and Mad Cow Disease. Plenum Publishing, New York 1998
“Belfast teenager rallies after revolutionary new CJD drug treatment.” 26 September 2003
Lawrence, Jeremy. Health Check: “Tonsillectomies show the fine line between doing good and harm” 29 March 2004 47
Lyman, Howard F. Mad Cowboy: Plain Truth From the Cattle Rancher Who Won‟t Eat Meat. Touchstone, New York. 1998
McNeil, Donald G. Jr. “U.S. Won't Let Company Test All Its Cattle for Mad Cow.” New York Times April 10, 2004
Morris, Chris. “Research raises new human-BSE fears” Canoe News (Canada) http://www.canoe.com/CNEWS/Canada/2004/01/18/pf-317283.html
Mother Earth News (Green Gazette) “Mad Cow Disease Hits Home.” April/May 2004
Murphy, Richard McGill.. “Truth or Scare: What Food Producers Need to Know About American‟s Demands for details on what they buy to eat.” American Demographics, March 2004.
Muzzi, Doreen, “BSE Still influencing Cattle Market” Southeast Farm Press March 3, 2004
Nobel Prize e-museum http://www.nobel.se/medicine/laureates/1997/illpres/brain.html
Organic Consumer‟s Association http://www.organicconsumers.org/madcow/GregerBSE.cfm
Ortiz, Jon. “California Lawmakers Push to End Secrecy over Meat Recalls.” Sacramento Bee April 1, 2004
People for The Ethical Treatment of Animals (PeTA) http://www.peta-online.org/feat/madcow/
Physicians Committee For Responsible Medicine (PCRM) press release “Mad Cow Disease” February 11 2004
Food Alert March/April, 2004 Vol. 5, No. 2 “Mad Cow Discovery Exposes Weaknesses in Inspection System.”
Press Release: “USDA, FDA Urged to Act Immediately to Protect Americans from Mad Cow Disease.”
Public Broadcasting System (PBS) http://www.pbs.org/newshour/bb/health/mad_cow.html#
Rampton, Sheldon and Stauber, John. Mad Cow U.S.A. Common Courage Press, Monroe, Maine. 1997
Rifkin, Jeremy. Beyond Beef: The Rise and Fall of the Cattle Culture. Penguin Books, New York. 1992
Rhodes, Richard. Deadly Feasts: Tracking the Secrets of a Terrifying New Plague. Simon & Schuster, New York. 1997
Shlachter, Barry. “Texas Cattle Ranchers, Packers Divided as Dwindling Herds Fetch Top Dollar.” Fort Worth Star-Telegram April 5, 2004
Sleeth, Peter and Dworkin, Andy. “Cow's 'downer' status comes into question.” The Oregonian 01/23/04.
Stafford, Jim. “Consumer Confidence Remains High for America's Beef Supply.” Daily Oklahoman, March 20, 2004
Sullivan, John. “Mad-Cow Disease Testing Is Unnecessary, Missouri Experts Claim.” Columbia Daily Tribune (MO), March 17, 2004
Time “Mad Cow Primer” January 12, 2004, Vol. 163 Issue 2, p48.
United Press International “Possible 'mad sheep' disease found” Thursday, April 8, 2004
United States Department of Agriculture (USDA)
Agricultural Outlook Economic Research Service August 2001 “Dissecting the Challenges of Mad Cow & Foot-and-Mouth Disease.”
“United States Department of Agriculture Evaluation of the Potential for Bovine Spongiform Encephalopathy in the United States Executive Summary “
Key Facts November 2001 Bovine Spongiform Encephalopathy (BSE)
Press Release March 29, 2004 “USDA Certifies Seven Laboratories for BSE Sample Analysis.”
USDA Response to “Report on Measures Relating to Bovine Spongiform Encephalopathy (BSE) in the United States” March 2004 48
Press Release No. 0105.04 “Veneman Announces Expanded BSE Surveillance Program” March 15, 2004
Organic Perspectives Newsletter May 2001 “BSE Crisis Boosts Consumption of Organic Dairy Products in Germany.”
arabian oryx: http://www.geoimagery.com/publishers/UAE/Gjlb65-0021UAEArabianOryxCrp.jpg
beef product flow chart: www.mindfully.org/ Food/Mad-Cow-BSE-GAO25jan02.htm
Carleton Gajdusek : http://home.sandiego.edu/~scare/page0.htm
cjd brain: www.infectiousdiseasenews.com/ 199606/cjd.asp
cow tounge: http://www.cite-sciences.fr/francais/ala_cite/science_actualites/media/1/1437/QACTU_IMG_PREVIEW.jpg
Farside comics: http://www.r-t-o-l.com/jeroen/ farside/archive/
lab rat: http://news.bbc.co.uk/media/images/38155000/jpg/_38155555_guide_mouse2300.jpg
lipstick: www.beautywithin.com/ images/lipstick.jpg
lotion : http://www.oilchem.com/images/lotion.jpg
Mad Cow: http://www.peta-online.org/feat/madcow/cowfoambig.jpg
Mad Cow Map and Key: www.pbs.org/newshour/bb/ health/mad_cow.html
Marsmallows: www.evilegg.org/.../marshmallows.jpeg/ view
Prion Theory: Time “Mad Cow Primer” January 12, 2004, Vol. 163 Issue 2, p48.
puma : http://www.people.virginia.edu/~rjh9u/gif/puma.gif
pyre of cattle.jpg:http://cfapp.rockymountainnews.com/cwd/killer/2.cfm
rendering garbage can: www.prijatelji-zivotinja.hr/ html/rendering.html
rendering vat: http://www.rendertech.co.nz/rendering_processes.htm
rhesus monkey: http://www.awionline.org/lab_animals/rhesus/82-200.jpg
scrapie brain : http://vetmed.chonnam.ac.kr/path/cyber/LaboraP/Clinical/case12/images/case12F3.htm
smiling beef clerk: www.arkcity.net/ stories/072403/
yogurt: www.scusd.edu/.../ info_on_calcium_dense_foods.htm
On a lighter note…