Subject: Re: BSE: IFST Position Statement Update, 27 March 1996

From: Oz <[email-masked]>
Date: Fri, 29 Mar 1996 08:50:04 +0000

In article <[email-masked]>, J Ralph Blanchfield
<[email-masked]> writes

>As to the first, there is no direct scientific evidence that BSE can
>be transmitted from cows to humans, and some research evidence
>suggesting that it cannot. Nevertheless, the emergence during the past
>two years of ten anomalous cases of Creutzfeldt-Jakob Disease (CJD) in
>a previously unrecognised pattern, led, in the absence of other
>explanation at present,  to the conjecture  that they were likely to
>have been caused by exposure to infected cattle brain or spinal cord
>before 1989 (at which time they were banned from the food chain) and

It was stated in the London Times that one of the cases had lived in
Australia for the last twelve years. Assuming he died at the end of 1995
he would have left UK in about 1983. Now it is clear from the initial
levels of the disease that any BSE in the UK herd was at very low levels
indeed (at worst) at that time. I, for one, find it hard to be very
convinced that this is a person that could have been infected by eating
UK beef whilst he was in the UK. If it was I would have expected very
large numbers to have been affected by now, which has NOT happened. If
you have more information, I would be grateful if you could post it.

>As to the second, muscle meat and milk have been shown to be incapable
>of carrying the infective agent, and measures have been taken, and
>strengthened, to exclude from the food chain certain parts of the
>animal, including all those parts shown to be capable of carrying the
>infective agent.  These measures require the most stringent
>enforcement and heavy penalties for evasion.

A point not well appreciated is that NO ruminants have eaten any meat &
bone meal since 1989 (1990 if you want to be certain).

>Scrapie is a fatal brain disease of sheep and goats endemic in many
>countries and recorded in the UK for well over 200 years.  It is
>apparently naturally transmitted between sheep and has an incubation
>period of 2½ and 4½ years. There is no good evidence that scrapie can
>be transmitted to man either occupationally or by eating sheep meat.

Indeed this is good evidence that it cannot be. If it were then we would
expect to see higher levels of CJD in those areas of UK where scrapie
infected sheep were (and are) eaten. This is not the case. The evidence
(200 years worth of it) here must surely be considered rather strong.
This is particularly true of sheep since the spinal cord is broken in
chops, and some people even eat it. (Me for example).

>Placental transmission has been identified as
>a likely route in sheep. 

I have always found this puzzling. Scrapie in sheep (it does occur at
low levels elsewhere in the world) at a marked level only seems to occur
in UK. Why is this? Some years ago I was discussing this and it was
pointed out that the UK is rather unusual in the way it farms sheep. In
most of europe the animals are individually penned before lambing, often
because weather conditions are poor outside, and the animals valuable.
In extensive areas like Australia and NZ the animals lamb unattended
outside, but individually and very extensively with high mortality. In
the UK (and particularly in scrapie infected areas) sheep are brought
down from the hill to lamb in groups in 'in-bye' fields at high density.
There are a lot of good reasons for this. However with lots of sheep
just lambed, or just about to lamb the sheep get a little confused. They
have the tendency to 'steal' newly born lambs and in particular to eat
each other's afterbirths. Eating the afterbirth is normal but usually an
isolated sheep only eats her own. In this situation it is easy to see
how scrapie can become a problem when other sheeps afterbirths are
consumed. It also offers an explanation of why the UK is one of the few
countries to have scrapie as a problem. Infection routes to the lamb are
thus not required. [All you didn't want to know about sheep.]

>There is at present no evidence of maternal transmission in cattle,
>and epidemiological evidence [Hoinville et al, Veterinary Record
>(1995) 136, 312] strongly suggestive of non-occurrence. 
                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
This should be stressed.

>The control measures in the UK for control of the epidemic in cattle
>were:
>
>     to destroy animals clinically diagnosed on the farm;

This has been very effective.

>      to prohibit the feeding of material containing animal protein
>derived from ruminants to cattle and other ruminants;

Note that this occurred in July 1988. Even allowing a year for odd local
stocks to be used we should be pretty certain that animals born after
1st Jan 1990 never ate any infective material.

>The banning of ruminant material from animal feedstuffs from July 1988
>has led, after a time lag (due in part to farmers using up their
>stocks of cattle feed after July 1988, but due mainly to the
>incubation period)  to a dramatic decline in new cases (30 percent
>drop from 1993 to 1994, over 40 percent drop from 1994 to 1995, and,
>up to 20 March 1996, a further 27.5 percent drop compared with the
>same period in 1995). 

Note that this is remarkable evidence that the original Southwood report
was CORRECT. At the time many so called experts asserted that this would
have no effect (Prof Lacey for example). They have been proven wrong.
Whilst it is 'fashionable' to deride experts, even when they have to
work with limited information, it's often not a very smart thing to do.
It is also worth noting that within a few years the problem, as far as
cow health is concerned, will be largely over.

---------

There seems to be considerable confusion over what things are at risk,
and what is not. I would offer the following comments.

1) Prime beef (ie joints, steaks etc) comes from animals of 15 to 20
months old. They were thus born in 1994, six years after the feed ban.
The chance of them having consumed any infective feed is thus very
remote indeed.

2) It has been stated that no bovine under 30 months has shown clinical
signs of the disease. So beef animals of under 20 months would seem to
be very low risk anyway.

3) Transfer of infection from cow to calf seems to be very rare indeed
at worst.

4) The infectivity of infected feed to cattle also seems to be rather
low. It is rather implied that any cow that consumes infected feed is
bound to get it eventually. The evidence is to the contrary. Herds that
had infected feed seem to have an infection rate of around 5% overall.
However the % of animals showing clinical disease has dropped off from
2% or so per year at peak through 1% and many have had no cases for two
years or so. The implication is that many of the animals were never
infected anyway.

5) I expect in another ten years this whole episode will be seen as a
nasty disease of cattle that caused very expensive hysteria amongst the
press, and as a result the whole population.

------------------------------- 
'Oz     "When I knew little, all was certain. The more I learnt,
        the less sure I was. Is this the uncertainty principle?"

---

From: [email-masked] (Arnold Chamove)
Date: 31 Mar 1996 07:05:52 GMT

In article <[email-masked]>, [email-masked] 
says...

> Some years ago it was
>outside, but individually and very extensively with high mortality. 

Not quite accurate.  A few leave their sheep to lamb unattended but as it is 
the lamb that produces the money, most farmers will walk a lambing beat twice 
a day during lambing. Since the weather is normally clearing (by planned 
mating) and the ram is only out for a short time, this is not an onerous task. 
Lambing precentages are normally well over 100% which argues for low 
mortality. I would say that most dead lambs are born dead.

The sheep does go off on her own to lamb and that is why lambing occurs in 
sheltered, large, familiar paddocks.

-- 
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ __ _ _ _ _ _ _ _ _ _ _ 
Arnold Chamove ; Massey University Psychology Dept; Palmerston North; N.Z.
E-mail: [email-masked];  FAX: +(64)350 5673;   Phone: +(64)25 460092
http://WWW.massey.ac.nz/~PsyWeb/staff/Chamove.htm
- - - - - - - -- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

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From: [email-masked] (Gaz)
Date: Mon, 1 Apr 1996 18:56:53 GMT+1 (BST)

>From: Oz <[email-masked]>

>>of carrying the infective agent,

Oh, and what was this proof? 

>> and measures have been taken, and

Which up to now have been a joke. Thousands of BSE infected cattle get into 
the meat supply, and checks comfirm that in addition a massive proportion of 
slaughter-houses fail to abide by the goverments (limited) measures.

>bone meal since 1989 (1990 if you want to be certain).

Hmmmm. What about non-ruminants. An awfull lot of them get eaten by people.

>>Placental transmission has been identified as

But the potentialfor it an cattle has been largely ignored. Indirect evidance 
would in fact tend to support it.....

Worried?

I am. Why hasn't the research been carried out...

>1st Jan 1990 never ate any infective material.

So why are they still going down with BSE? Goverment figures suggest that the 
incidence of BSE is on the decline. Farmers will tell you that the incidence 
is still on the up. Mainly because the goverment payment to farmers for the 
slaughter of a BSE cow is so low (why is this....) that many send them to 
market at the very first sign of BSE. Thus they are never shown in the 
"official" stats.

>>up to 20 March 1996, a further 27.5 percent drop compared with the

No. See above. Most dairy farmers will tell you that BSE is at levels thay 
have never seen before in the past. Goverment methods of finding and recording 
these BSE figures are in error, if the farmers are to be believed.

Why was compensation reduced in 1994? If you really want to find BSE infected 
cattle the smart thing to do would be to make the compensation higher than the 
market price for the cow.

Gaz

---

From: Oz <[email-masked]>
Date: Mon, 1 Apr 1996 18:00:35 +0100

In article <[email-masked]>, Arnold Chamove
<[email-masked]> writes
>sheltered, large, familiar paddocks.

Ah, must have been the Australians then!

Mind you with reports of 2000 ewes/shepherd he is a busy man. On the
other hand NZ has been instrumental in breeding 'easy-care' sheep. A
development that I personally applaud, a real advance.

---

From: Oz <[email-masked]>
Date: Mon, 1 Apr 1996 22:22:09 +0100

In article <[email-masked]>, Gaz <[email-masked]> writes
>Oh, and what was this proof? 

Ref: SEAC HMSO Sept '94.

>the meat supply, 

How do YOU know? 

>and checks comfirm that in addition a massive proportion of 

No. A small minority. They were found by regular govt random checks. I
don't think you could possibly describe the measures as 'limited'. What
would you suggest ought to be done further, and why?

>Hmmmm. What about non-ruminants. An awfull lot of them get eaten by people.

None as of now. No cases have ever been found in the pig or poultry
population. It would be helpful to stick to facts rather than innuendo.

>would in fact tend to support it.....

No infective agent has ever been found in placental tissue. Same
reference as above. More innuendo unsupported by facts.

>I am. Why hasn't the research been carried out...

What research is that?

>is still on the up. 

Rubbish. You don't know what you are talking about. I doubt you know any
UK farmers who have had BSE in their herd. More innuendo, actually
downright untruths here. 

>Mainly because the goverment payment to farmers for the 
>slaughter of a BSE cow is so low (why is this....) 

Eh? It's quite acceptable. Your information is incorrect. Again.

>that many send them to 

You have obviously never sent animals to market. The buyers are shrewd
and knowlegeable people. So is the RSPCA man, and the govt vets. No
chance. Dream on.

>these BSE figures are in error, if the farmers are to be believed.

Nonsense. You clearly don't know any british farmers. You are dreaming
again. 

>market price for the cow.

I think you are trolling. 

Since this is a serious subject, that has all the capability of
bankrupting large numbers of your fellow coutrymen, causing a serious
number of suicides amongst farmers and their staff and costing everyone
in britain thousands of pounds it is in very bad taste. I can only
assume that you are a student at Aberystwyth Univerity who thinks
spreading untruths and innuendo is a good prank.

You might try to grow up.

---

From: Oz <[email-masked]>
Date: Fri, 5 Apr 1996 09:13:19 +0100

>Oh, and what was this proof? 

Actually there have been quite a few studies I have come across, but
since I am an individual and not an academic or organisation I don't
have access to cross-referenced libraries (as you do) I have not the
time to look out a long list. A manual look threw up the following:

Middleton & Barlow, 1993 Vet Rec 132, 545-547 Feeding study.

Neuropathogenesis Unit, Edinburgh, Vet Rec, 1995 136 23-592
(Intracerebral)

Doubtless you can find more yourself, if so please let me know and I
will try to obtain copies, although it's difficult for me.

>Which up to now have been a joke. Thousands of BSE infected cattle get into 

Evidence please.

>slaughter-houses fail to abide by the goverments (limited) measures.

Evidence please. 
As I understand it a small number of tiny abbatoirs got a bit careless.
The inspectors found them, the govt. published the information. One (at
least) is being prosecuted. How transparent do you want it? You get the
truth, you blow it up, you complain of lies and deception. Do YOU
habitually lie and misrepresent? Oh. Well actually most people don't.

>Hmmmm. What about non-ruminants. An awfull lot of them get eaten by people.

Not at present, but they were. 
There is still no evidence of any transmission by feed to pigs and
poultry. Please don't quote laboratory transmission to pigs by massive
infected brain extract, it's not a customary method of feeding pigs.
Also please note that clinically infected cows are incinerated, and all
brain and spinal cord (the only material found to be infective from
cattle) from ALL cattle is removed from the food chain, infected or not.
Anyway, at present no cattle M&B meal is being fed to anything. A
serious of a disposal problem.

Pretty rock solid, yes?

>But the potentialfor it an cattle has been largely ignored. 

AARRGGH! It was the main worry in 1988. So far evidence has shown it to
be nil, or insignificant. We are now many years down the road, if it
were to be a problem it would have surfaced by now. At worst it will
result in a very, very low level of disease indeed for another
generation of cows.

>Indirect evidance 

No, I am tired of pointing this out. Direct evidence shows quite the
reverse.

>I am. Why hasn't the research been carried out...

AARRGGHH! Over 300 papers published, most if not all of the things you
have worried about have been investigated. Please go to your univeritly
library and look them up! You are in the privilaged position of being
able to do so, take advantage of it.

>So why are they still going down with BSE? 

You DO understand the epidemiology? You DO know how long a cow lives in
a dairy herd? So why ask this stupid question. Yet again.

-----

Oh-hum, sorry folks. I wasn't expecting a long visit here, so I omitted
to reset the defaults for this group. As a result I may have answered
several posts twice (I *hope* not three times). I have reset the
defaults to more sensible figures.

My apologies for any inconvenience caused.

<Embarrassement!>

------

---

From: [email-masked] (Jack Campin)
Date: 5 Apr 1996 23:59:48 GMT

>J Ralph Blanchfield <[email-masked]> writes
> muscle meat and milk have been shown to be incapable

The abnormal prion proteins are expressed in all nervous tissue, are
they not?

Muscles contained nerve tissue last time I looked at an anatomy text.

Is Ralph's definition of "meat" some product consisting solely of
contractile cells and collagen?  If so, how on earth is it made?

-----------------------------------------------------------------------------
Jack Campin                 [email-masked]        [email-masked]
T/L, 2 Haddington Place, Edinburgh EH7 4AE, Scotland       (+44) 131 556 5272 
--------------------  FERMAN PADiSAHIN, DAGLAR BiZiMDiR  --------------------

---

From: Oz <[email-masked]>
Date: Sat, 6 Apr 1996 07:25:04 +0100

In article <[email-masked]>, Jack Campin <[email-masked]>
writes
>The abnormal prion proteins are expressed in all nervous tissue, are

I can't remember seeing any statement or abstract that states this. Do
you have a reference? However if so wouldn't we see parts of the body
that are weak in infected animals (legs for example) were this the case?
What you actually see is a discoordinated animal that has no problem
with weak limbs at all. So it would, on reflection, seem likely that
peripheral nerves are not effected.

It is not so uncommon to find diseases that only attack either the
central nervous system (brain and spinal cord) or the peripheral one.
Polio being the most obvious, presumably whatever Stephen Hawking has
takes out the peripheral nervous system, but clearly leave the brain
intact. Perhaps we have a neurologist in the group to comment on this?

>Muscles contained nerve tissue last time I looked at an anatomy text.

Certainly. However they have not been able to transmit BSE to suceptable
mice by injection muscle from terminally BSE infected animals directly
into the brain.