"Mad Cows," rBGH Hormones Related

(IPS) LONDON -- The spread of Bovine Spongiform Encephalopathy (BSE), or so-called "Mad Cow disease," may have been encouraged by Western industry's increasing use of artificial growth hormones to boost profitable milk and meat production.

The issue was raised in the U.S. as early as 1993 by Michael Hansen, Research Associate at the Consumer Policy Institute, during testimony before the Veterinary Medicine Advisory Committee on Potential Animal and Human Health Effects of its use.

Cows treated with growth hormones (rBGH) require more energy-dense food. This has usually been provided as meat and bone meal derived from "rendered" animals -- animal bodies processed into food for other animals which are herbivorous.

Hansen pointed out that problems arising include sheep suffering from the BSE-related disease of scrapie, and "downed cows" -- apparently healthy cows simply drop dead. He also noted that researchers had begun to suspect a link between BSE and downed cow deaths.

Mammals contract BSE by eating infected meat, which raises the possibility that BSE infection may be carried into rendered animal-based feed given to rBGH-injected cows.

The use of rBGH was approved by the (FDA) in November, 1993, but its use is banned in many European countries, Australia and New Zealand.

There is mounting evidence that it may compromise the health of both cows and humans. But intensive lobbying by the chemical companies has helped ensure widespread use in the U.S. and Britain.

Now it is being promoted heavily in many developing countries as a solution to food shortages. But this could be a false economy for the developing world.

Under rBGH treatment cows are kept in a perpetual cycle of gestation and lactation which wears out their bodies quickly, cutting the normal life span of 20 to 25 years to five or less.

Already, cows are overproducing milk. In 1930, the average cow produced 5 kilograms of milk per day, but by 1988, milk production was at 18 kg a day. With rBGH injections it rises to 22 kg per day.

It is because rBGH-injected cows cannot consume and digest enough normal food to support this level of production that they are fed a highly concentrated diet. They are also more vulnerable to disease because their body systems are overworked. Thus they are often given increased doses of antibiotics to cope with the disease.

Residues from the disease and from the drugs then get into the milk. This added stress on cows lowers fertility as well as life span, reducing the number of calves each cow can produce.

British scientists Dr. Eric Millstone and Dr. Eric Bruner, hired by Monsanto to review data on rBGH, say they were prevented from releasing findings that showed a definite increase in cases of mild inflammation of the mammary glands (mastitis) in rBGH-treated cows.

"I find it very curious that Monsanto should object to our paper -- a relatively harmless analysis which shows some small negative effects," says Bruner. "If they're seeking to suppress these data, as they have for the last three years, then could it be that there are other questions which we don't yet know about?"

One major worry is that hormonal and antibiotic residues in milk and meat (a large percentage of hamburger meat is made from "burned out" dairy cows) will affect human health, especially children.

An earlier onset of puberty is thought to be caused by the already increased use of hormones in cows, and girls who menstruate before the age of 12 have a higher risk of contracting breast cancer later.

The increase in antibiotic use in animals also adds concern about increased antibiotic-resistant bacteria.

Cows injected with rBGH produce much more of an insulin-like growth factor, IGF-1, whose molecular structure is the same in humans and cows, increasing the likelihood of transmission through milk and meat consumption. In humans, IGF-1 is linked to acromegaly, a disease involving the abnormal enlargement of the hands, feet, nose and chin. Increased levels of IGF-1 have also been linked to colon tumours and cancer, particularly breast cancer in women.

Just two-fifths of a hectare can feed 20 times as many people eating a pure vegetarian diet than it can feed people eating an animal-based diet. Clearly cows are big business and the methods being used to boost profits could be disastrous in the long term. The BSE fiasco may just be the first of many.

The announcement by British scientists after the identification of a new pattern of the human Creutzfeldt-Jacob Disease (CJD) that they cannot rule out the possibility that BSE may be transmitted to humans has turned the medical and scientific community upside down.

BSE is one of a group of little understood infectious diseases which affect various animal species and man. They are not caused by a virus or bacteria but by an agent known as a "prion" protein which is thought to cause a slow biochemical chain reaction provoking brain protein molecules to change form.

The result is transformation of the brain to a sponge-like state which is always fatal.

Prions have been shown to be very stable and can withstand temperatures, radiation or antiseptics which would kill other infectious agents. They also appear to provoke no immune response in victims.

Disease caused by this agent has long been known in sheep, as "scrapie," but rarely occurred in cows before the 1980s. The present BSE epidemic is believed to be the result of incorporating sheep offal in cattle feed -- indicating that this type of disease can be transferred between species.

Sheep offal was banned from animal feed in 1989, but BSE has a long incubation period. There are currently questions about how the disease is transmitted and which organs are infected.

In cows, investigations suggest that only the brain, spinal cord and retina are implicated. How easily transfer between species occurs is also a mystery as there are no recorded cases of humans developing disease from infected sheep -- sheep's brains and eyes are routinely eaten in some cultures.

The human form, CJD, is quite rare worldwide. Symptoms of CJD include shaking, nervousness, forgetfulness, loss of balance, hallucinations and wasting.

Victims decline rapidly to a state where they cannot walk, talk or look after themselves. In Britain about one person a week dies from CJD. In Europe, the figures for 1994 are within a range of 0.53 per million to 1.04 per million, the highest rate recorded in the Netherlands.

Historically, CJD has usually struck the over-55s. No teenage cases of CJD were recorded before 1994 and there have only been five worldwide. Some victims contracted the disease by being treated with infected extracts from human pituitary glands to boost growth or aid fertility. Seventeen have already contracted CJD from the treatment, 15 are dead and another 1,900 have been warned they are at risk.

The recent cases in Britain however show a different pattern, which is fuelling the growing concern in the country and across Europe.

Since 1994, there have been four reported cases affecting teenagers in Britain. In addition, four farmers who worked with BSE-infected herds have died of CJD in the last three years.

In 1994, there were a record 55 deaths blamed on the illness - double the figure for 1985 -- but government scientists insisted at the time that the figures were in line with the average worldwide rate of about one in a million, regardless of local eating habits and the presence of BSE in local cattle.

But recently the SEAC committee cited 10 cases of CJD among people under the age of 42 which could be linked to eating infected beef but which could not be explained by genetic analysis or medical histories.

The British Government has now accepted SEAC's recommendation that there should be "urgent" further research. But there is additional concern that children may be more at risk of contracting this new form of CJD.

Stephen Dealler, a microbiologist at Burnley General Hospital in Britain who has been studying CJD since 1988, fears there may be an epidemic over the next decade in those who are now children. He says a human epidemic would start some 15 years after that in cattle and points out that a total of 250,000 BSE-infected cows were eaten in 1990 alone. At worst, he warns some 10 million people could be infected by 2010. SEAC Chairman Professor John Pattinson says the next year may be crucial in showing the real extent of the threat.

Microbiologists like Richard Lacey have been warning of the risks for six years. He estimates that some 500,000 people could be affected by 2010. Lacey accuses the government of putting financial concerns and the interests of Britain's multi-million-dollar beef industry above the health needs of its citizens.

Dr. Harash Narang agrees. He was dismissed from the Public Health Laboratory Service two years ago after developing a quick test for BSE in cows. He believes he was fired because he knew too much after the government ignored vital evidence about possible links he presented to a Select Committee in 1990.

"I found two out of four cases of Creutzfeldt-Jacob Disease that I studied were atypical. That means the pattern was different from other cases and they resembled the disease in cows."

Narang has been studying the disease since 1970. In 1972 he identified a structure known as a nemavirus which indicated the presence of BSE in the brain. Based on this knowledge he offered a diagnostic test for the disease to the Ministry of Agriculture in 1988 but it was rejected. "It's not that the test doesn't work or costs too much money, it's simply the cost of the animals they would have to kill," Narang says.

Narang has continued with his research sponsored by businessman Ken Bell but claims to have faced serious harassment. His car tires were slashed five times, his brakes tampered with and his Newcastle flat broken into and research papers disturbed.