Dr David Marlin's Ragwort Mistakes.

 

Once again I find myself expressing my honest opinions and debunking some misleading anti-ragwort propaganda. One of the problems is that there is a bubble in the equine community. Incorrect facts circulate inside this bubble and are considered correct because they have been repeated so often.

I don’t suffer from this. It was abundantly obvious that misinformation was being circulated even before I started my researches over two decades ago. I get my information from the scientific literature. As regular readers will know I have been studying the science on this for more than two decades.

Today I am debunking an article posted on Facebook by one David Marlin. He is attacking another posting made by someone else elsewhere on Facebook. I'm going through it line by line.

He starts by quoting this other article and criticising things that he thinks are wrong but where the evidence tells us something different.

Dr David Marlin

RAGWORT POISONING IN HORSES 

Lots of "misinformation" about RAGWORT.

This is unquestionably true. There is so much misinformation that there are entire blogs and websites devoted to documenting just some of it as I will show here today.

RAGWORT has been "wrongly labelled as a weed"

It is quite normal and usual for people who study wildflowers not to like them being called weeds.

People who say RAGWORT is a problem for horses are "Scaremongering".

There is no question at all that scaremongering exists. I’ll show examples in this posting!

There's apparently a lot of "Fake News" being spread about RAGWORT and horses.

Unquestionably this is true. This blog is all about it!

RAGWORT is apparently "Not a threat to horses".

This is a small quote taken out of context

An "average horse" would have to ingest over "50kg of RAGWORT" apparently for it to be "Toxic".

Now this is where the bubble comes in. Let's look at this one. Is it reasonable to say this? There will be many horse people who will say that it is nonsense of course, but actually it is not!

One of the first things to determine is how toxic the plant is, and I think it's fair to assume that what the author of the video meant is that it takes 50kg to kill a horse.

We can do this and we can go to the scientific literature. Well, there is an article in the American Journal of Veterinary Research, written by well-known ragwort toxicology experts and we find this statement

"Horses, cattle and rats are susceptible to toxicity (chronic tansy ragwort lethal dose is 5% to 25% of body weight.)"

Incidentally, tansy ragwort is just the American name for our ragwort.

A quick google, which we can assume the author of the video did gives an average horse weight of 700kg to 1000kg. For the lower figure, 5% of body weight is 35 kg and 25% is 175 kg, and the figures for the upper figure are 50 kg and 250 kg. The published research shows that this is correct!

"...We are wrong to remove them [RAGWORT]".

It is a common place opinion for conservationists not to like people removing wildflowers.

These are all pearls of wisdom from some nameless "expert" from a page called WILDLIFE CONSERVATION IN THANET!

Not sure how owners who have lost horses to ragwort poisoning will feel about his comments.

It is at this point that it becomes clear that he doesn’t properly understand the issue. I’ll explain it below but how would they possibly know that they have lost horses to ragwort poisoning! People inside the bubble might believe it is easy to tell but as I will explain below it really isn’t.

SOME RAGWORT FACTS......

Of 865 liver samples received by pathology services over a 5 year period, 72 (8.3%) were found to have evidence of megalocytosis; an indicator of ragwort poisoning. This actually translates to 57 samples a year.

Hang on a minute! The maths is wrong here! 72 divided by five is 14.4 not 57!

The really crucial thing here is that megalocytosis does occur in ragwort poisoning, often known technically as Pyrrolizidine Alkaloid Toxicosis after the toxins in ragwort. BUT the important fact is that it has other causes too. Most significantly mycotoxins, toxins produced by often invisible moulds in feed.

In fact the most recent research by Professor Andy Durham in a paper on these mycotoxins in horses says,

“Liver disease is commonly encountered in equine practice both as clinical and subclinical disease. Outbreaks of hepatic disease are common and once often were suspected to be caused by pyrrolizidine alkaloid (PA) toxicosis,although more recent evidence suggests that PA toxicity is far less common than generally suspected”

REMEMBER - this is going to be a gross underestimation of the number of cases as the majority are unlikely to have samples submitted for diagnosis. Some cases will be treated, some will die, some will be euthanised without a diagnosis.

This is obviously bad thinking since we know there is no way of identifying cases with certainty.

Then there is more bad information.

In 2014 a BEVA survey reported that of 303 vets, 41% had seen at least one suspected case of ragwort poisoning in the past year. Each vet was seeing at least 2 cases per year. 49% died or were euthanised.

It is first necessary to establish what a suspected case can be. The British Horse Society actually published a case in their newsletter where they described a vet turning up to a case and pronouncing on the spot that it was ragwort poisoning without further tests at all.

An equine charity responded to me with a four letter insults on-line insisting they knew of cases based on blood tests. As an expert I can tell you these only tell you there is liver damage which has a multiplicity of causes but they had evidently, it seems, been informed by their vet that blood tests were enough.

More bad information again.

In a survey by the BHS & DEFRA in 2014, 19% of respondents knew of a horse that was susepcted[sic] to have been poisoned by ragwort, with a defintive[sic] diagnosis in 21% of those cases. It was reported that 39% died or were euthanised.

First of all let’s deal with the issue again of a claimed definitive diagnosis. As I have said the evidence is very very clear you cannot have a definitive diagnosis.

It is this bubble again. I have checked and checked. There are scientific papers going back years, one of them in the highly respected journal Nature says that poisoning by fungal toxins is “indistinguishable from ragwort.”

Secondly this survey was RIGGED. First of all there were leading questions telling people ragwort was appallingly dreadful at the beginning but worse than that there was an article in the BHS newsletter instructing people to fill in the survey AND IT GAVE THEM A CASE that they could use to justify the reply that they had heard of to use. This was the case with a vet turning up and pronouncing a diagnosis without tests which I wrote about above.

In any case knowing of a horse that had ragwort poisoning is a very poor question without proper qualification of how they knew. Was it this year or 50 years ago?

Even a few mouthfulls [sic] of ragwort will cause some degree of IRREVERSIBLE liver damage. The more that is eaten, the more the damage. Damage accumulates over time! Moore RE, Knottenbelt D, Matthews JB, Beynon RJ, Whitfield PD. Biomarkers for ragwort poisoning in horses: identification of protein targets. BMC Vet Res. 2008 Aug 8;4:30.

Regular readers will notice the name Knottenbelt. Yes this is the man who claimed it is poisoning the cinnabar moth and who claimed it was a serious problem in South Africa, where the plant has never been recorded.

This is a common claim but as I explained above the literature tells us that small doses have no effect.

As little ragwort as 1% of bodyweight can prove fatal over time - Fu, P. P., Q. Xia, G. Lin & M. W. Chou. 2004. Pyrrolizidine alkaloids - Genotoxicity, metabolism enzymes, metabolic activation, and mechanisms. Drug Metabolism Reviews 36: 1-55.

Just look at this reference! As soon as I saw it I was on the alert. I am very familiar with this paper. It DOES NOT SAY THAT! It is not about that kind of thing at all. What is going on here? Is this just carelessness or is it a deliberate attempt to mislead? In my honest opinion if someone wanted to bamboozle people with bad science this is exactly the sort of paper that would be used it is 55 pages long and full of degree level biochemistry.  In fact it is worse than that I took a random sample of text and put it through something that calculates a measure of readability called the Gunning Fog  Index where Fog stands for Frequency Of Gobbledegook. An index of 17 requires you to have a university degree but this actually came out at 19.5! Most people wouldn’t have a clue about what it says. The word “ragwort” does not even appear in this scientific paper!

On the basis of what I have read in over 2 decades of detailed study of what is known from the scientific literature, claiming that 1% of body weight  being fatal is I something I can honestly describe as scaremongering.

The risk from ragwort poisoning is not simply from plants grazed in paddocks but from ragwort contamination of feedstuffs such as hay or haylage.

The ONLY problems are in preserved forage or where pasture is so bad that they are starved into eating the plant.

Contrary to the video, pyrrolizidine alkaloids (the toxic compounds in ragwort and other plants), are absorbed through the skin. The absorption is low, not non-existent. If you handle ragwort frequently without gloves you will develop liver damage.

Where is the evidence? First of all he overestimates the toxicity of the plant and now he is making statements of something definitely happening when there is actually no case of people being poisoned in this way in the scientific literature.

The issue here is the bubble again, believing in things in general circulation amongst horsey people rather than looking properly at the scientific literature.

If small amounts are absorbed they are not necessarily toxic in their absorbed form. They would then have to be converted into that toxic form, the first step of this usually takes place in the gut so it wouldn’t necessarily happen happen but if it did they then have to go through another step and there are several things than can happen. They can just be broken down. They can be detoxified by reacting harmlessly with other substances, which includes the one that detoxifies paracetamol. If tiny amounts arrive at the DNA molecules where harm can happen then there is a DNA repair mechanism.

There are several published scientific papers showing that animals fed only small amounts of a plant with the same toxins as ragwort had no damage to their livers!

So ragwort posoning [sic]does occur in horses. It is realtively [sic] rare, but this likely due to its removal from many areas horses and ponies graze.

"However, a justification or recommendation for relaxation in ragwort control would be a risky strategy as it is possible that the

apparently low prevalence of ragwort toxicity in horses might be as a result of generally effective pasture management that, if relaxed,

might lead to an increase in toxicity cases." Andy Durham, BSc, BVSc, CertEP, DEIM, DipECEIM, MRCVS, Liphook Equine Hospital, Veterinary Record, June 13, 2015.

 Notice the use of authority to make a point all those letters after his name are used to give an air of authority. It is a big no no in science. The question to really ask is if this author is really aware of all of the falsehoods, including those in the posting I am criticising. My honest belief is that the posting I am quoting is a particularly egregious example of the common place habit of equine activists of carelessly acting in a manner that at the very best is grossly overstating the problem.

 Postscript - “If you own horses, ponies or livestock you must not allow them to graze on land where you know ragwort is present” https://www.gov.uk/.../stop-ragwort-and-other-harmful…

This is another  example of argument from authority a no no in scientific thinking. Regular readers will know that Defra is a lousy source of information. They once told people our native ragwort was on a list of dangerous foreign invaders. It is obvious to me as an expert that they are not experts.

"Pyrrolizidine alkaloids (PAs) constitute a class of plant toxin associated with disease in humans and animals. They are found in a wide variety of plant species in the world and it is estimated that ∼3% of the world's flowering plants contain toxic pyrrolizidine alkaloids. The toxin is present in more than 12 higher plant families, among which three families, Compositae (Asteracea), Boraginaceae, and Leguminosae (Fabaceae), contain most toxic PAs." RAGWORT belongs to the family Compositae (Asteracea). Ibanez, G. (2005) Encyclopedia of Toxicology (Second Edition) https://www.sciencedirect.com/.../encyclopedia-of-toxicology

So, MR WILDLIFE CONSERVATION IN THANET..…

So what! It isn’t an issue that they are toxic we all know that. However toxic doesn’t necessarily mean dangerous and as I have pointed out repeatedly he gets his facts wrong.

1) Please get your facts right

2) Horse owners aren't looking to pull up every single ragwort plant in existence. Only the ones in the fields where our horses and ponies graze.

This simply isn’t the case. The British Horse Society tried to legislate for control on public lands and Professor Derek Knottenbelt has been quoted repeatedly in the press saying, "It is toxic to humans, so what the hell are we doing with it in this country?"

And frankly, if we do want to remove them, that is absolutly[sic] none of your business!

Actually we have a biodiversity crisis, that with climate breakdown threatens everyone’s future. Ragwort hysteria actually effects many of the nature sites in Britain. Unless you are some kind of weird anarchist you have to expect that we have rules to live by and that conservationists will work to conserve nature. It is really unacceptable to have equine activists inventing nonsense to scare people and I really really do have good evidence of this happening.

Vets repeat result of crooked ragwort survey.

Today I am giving my honest opinions on a page on ragwort by the Sussex Equine Hospital. I need this to post for two different comments I have seen on line. One is putting this page forth as a good example of information, which it clearly isn't and another asking about British Horse Society surveys, which are appallingly bad. 

 The page is an example how even vets get things wrong. It is likely that in this case it is largely inadvertent and that some of it is ignorance which is common even in equine vets and that largely the problem lies with the British Horse Society.

The article starts with a set of poor claims:-

Ragwort (also known as Senecio Jacobaea) toxicity is one of the most common causes of poisoning to horses in the UK. A recent survey by the British Horse Society showed that 20% of respondents knew of a horse that had been affected.

Firstly, no one can know properly that a horse can have ragwort poisoning without additional evidence other than  just symptoms. This is because other substances can cause the same damage at an atomic level.  So you cannot say how common it is! It is in some of the modern textbooks and has been known about since 1961 but many vets don't know this. You see this mistake all the time and I have had to correct them in the past. Just to explain why I am so certain about it. A colleague attended a ragwort meeting where a veterinary professor was talking  and got the information about aflatoxicosis ( A kind of mould poisoning) causing identical symptoms from him. There is also this quote from a recent paper by  the Animal and Plant Health Agency (APHA) in the Veterinary Journal about a rare case of pigs and ragwort.

"Acute aflatoxicosis could cause similar pathology but the clear access to ragwort plants and the knowledge that pigs on other units on the same commercial pig diet were healthy, pointed away from this potential cause."

We know there is no reliable test for ragwort poisoning. In this case it was obvious with the pigs, but in the overwhelming number of horse cases it isn't.

The second point that a survey by the British Horse Society said that 20% of respondents knew of a case. Of course the first point applies and they couldn't have known of a case but we need also to look at the survey.

The bent survey is a speciality of the British Horse Society. They are well known for running them and for repeating them. First of all there is the British Equine Veterinary Association survey which they publicised widely. As I have previously written, I attended a ragwort symposium in the Netherlands last year and their survey methods had a room full of top ragwort scientists hooting and moaning in derision.

First they designed a poor survey they didn't check how diagnoses were achieved properly. They didn't check for duplicate cases where more than 1 vet was involved etc.. As I've said there is no definitive test so how could they know.? They got a tiny number of responses just 4% and then outrageously multiplied the figures they got as if everyone had answered! 

Those figures were as bent as a butcher's hook and yet the BHS publicised them. Worse people selling ragwort controls used them, illegally, in their advertising. I took these to the Advertising Standards Authority and got them taken down.

Now we come to the survey in question and wait for it this is a real corker! First of all they put an article in their newsletter, with a highly emotive article about how terrible ragwort was see the excerpt below.  NOTE they provided an example of supposed ragwort poisoning. Actually they claimed a vet turned up and proclaimed it was ragwort poisoning on the spot. This may well have happened but is not what a vet should do to establish poisoning. 

This is the excerpt I mention above.

"Our Welfare Department recently heard a harrowing story of Ragwort poisoning from Ruth Anderson, who kept her horse in a yard on the south coast...... One morning she found her horse, covered in mud, and looking as if she had sweated up during the night. It appeared she may have had colic or had been charging round like a mad thing (spooked over something). so we kept an eye on her," said Ruth. "Then she wouldn't eat her dinner, she had a 'mad twitch' and was pitching her head to one side. "

This of course biased the survey. It is well established that these sorts of things bias surveys and rig the results. You can read more details of the article here https://www.ragwortfacts.com/british-horse-march-april-2015.html

( You can also read about yet another survey where they had used people seeing horses near ragwort in a previous well publicised survey, which isn't necessarily a problem. It didn't stop them using it as a scare story in the press.)

The survey then started with a false and leading question asking if people knew that ragwort was "extremely poisonous" to horses. This in scientific terms isn't true. Extremely poisonous substances are thousands of times more toxic than ragwort! Of course this biased the survey yet again.

Then and this is the real corker! They asked people if they had ever heard of  a case, after providing an example for them to know about in the newsletter article asking them to fill in the survey!

Of course all of these factors, biasing the survey and the impossibility of really knowing ragwort caused all the cases rendered the survey figures useless, but it didn't stop them from publicising this figure which the vets have repeated.

Then there is this comment which you see all the time but, honestly, if you look at the evidence , it isn't true,

"The effect is cumulative and symptoms may not be seen for up to a year after exposure."

First of all the biochemistry shows that the damage only occurs and therefore is only cumulative if a threshold is exceeded. The toxins can be destroyed or inactivated and there are repair mechanisms. Secondly there are TWO scientific papers describing experimental poisoning experiments where, as expected, small doses have no effect. 

Then again inaccuracies.

"The poison effects 3 main body systems - the liver, the central nervous system (brain, spine and its associated nerves) and the skin."

The alkaloids in ragwort affect the liver  and the other symptoms are caused by liver failure which stops the liver breaking down toxic substances that build up naturally in the body.

Then this old chestnut of a falsehood which regular readers will recognise!

" However, the Weeds Act 1959 made ragwort control a legal obligation for owners and occupiers of grazing land. "

This is of course utter nonsense. The law says no such thing. You may be ordered to control ragwort, but in the absence of a rare order there is no obligation to do anything. Maybe the vets got this off the British Horse Society too.

Finally, I'll post a piece of TV comedy as I have before. It is from the comedy Yes Prime Minister where Sir Humphrey Appleby explains how to rig an opinion survey in an exactly similar way to that which the British Horse Society does, by asking leading questions.

Canterbury Horse Rescue Lousy Charity's Ragwort Nonsense!

In my honest opinion Canterbury Horse Rescue is an absolutely lousy charity. They have let an abusive, ignorant, arrogant and dim-witted individual to tweet on their behalf. This is clearly a clueless ignoramus who spreads environmentally damaging scare stories.

When someone is challenging you and provides links, then you need to examine the evidence. If you don’t understand it then don’t challenge it.

I’ll post the twitter thread below. This happened some time ago but I have recently been researching the central fact at issue, that there cannot be a  general definitive diagnosis of ragwort poisoning. This is because mouldy food such as hay can contain aflatoxins which have the same effect at an atomic level and therefore produce damage that is, "indistinguishable from ragwort”. That quote comes from a paper in one of the world’s finest scientific journals Nature. It was printed there only a few years after the paper which announced to the world that the structure of DNA had been discovered, leading to the Nobel Prize for its authors.

First of all Canterbury Horse Rescue posted a quote tweet replying to some one who had seen “introduced Silver Ragwort” growing wild somewhere as it occasionally does. This is Jacobaea maritima. This is a different species to the native (Common) Ragwort (Jacobaea vulgaris) so there are no laws mentioning it anyway! However the information they provided to their followers was nonsense even when applied to (Common) Ragwort.

First of all Canterbury Horse Rescue falsely claimed that the council had a duty to clear. No such duty to control for councils exists in the law for any species of ragwort. It also implies the plant is scary and dangerous because such a law is needed. This is misleading.

Then they said you must wear gloves when handling it. This is a repetition of a well-known scare story and myth. It was looked at by some Dutch scientists some years ago who concluded it was nonsense. This is also misleading.

Then they said it was dangerous to pets. There is a standard veterinary text book on plants toxic to cats and dogs. Ragwort isn’t even mentioned! So this is a misleading scare story yet again!

In general the rule is that if an equine organisation says anything negative about ragwort then it will be misleading in some way or another, but Canterbury Horse Rescue really take the biscuit!

Despite being provided by Friends of the Earth’s briefing with detailed information and proper scientific references, this ignoramus ignored the evidence, which includes telling them that there is no reliable test for ragwort poisoning, and carried on arguing.

There are very clear rules placed on registered charities by the Charities Commission which have been utterly ignored by Canterbury Horse Rescue. They did not properly examine the evidence given to them.

Let’s look at their claims regarding Defra hat they said, and it's false by the way, that ragwort is our top killer.. The first thing to realise is as I have proved many times over the years Defra haven’t a clue about the subject. Just to give one example of their bungling ignorance. They once told everyone that ragwort, which is an ecologically important native plant, was on a list of dangerous foreign invaders!

As for using Defra as a source, the bungling ignoramus from Canterbury Horse Rescue had already been told via the Friends of the Earth briefing that there was no reliable test for ragwort poisoning so they needed evidence to show that was wrong. Argument from Authority is one of the biggest errors you can make in thinking.

As the famous American scientist Carl Sagan wrote in his book. The Demon-Haunted World: Science as a Candle in the Dark

"Mistrust arguments from authority....  Too many such arguments have proved too painfully wrong. Authorities must prove their contentions like everybody else."

Defra are often rather slow and reluctant in replying to Freedom of Information Requests and often don’t actually have the information that you’d expect them have to make some of their claims. They cannot prove their contentions.

Canterbury Horse Rescue probably didn’t ask, and certainly didn’t ask for proof when they’d already being given the requisite information by Friends of the Earth.

Defra are also currently lying about the law to people, with regards to ragwort. It is very easy to prove this as the law is written down in black and white and their information clearly misrepresents it. They claim if you follow their very badly researched advice you will avoid fines when what they fail to tell you is, a lie by omission that the law requires them first to tell you in a specific legal order to control it and then and you can only be fined if a court finds that you unreasonably refused to follow that order,

Some people do form their opinions on the basis of tradition and authority but it is important to know what the research says about such people, on average clinical tests show they are less intelligent!

The basis of the Canterbury Horse Rescue ignoramus's argument was not only wrong but possible evidence of a clinical mental issue!

Here is the actual thread of this discussion on twitter. The bad language used brings them into disrepute and wasn't justified.

The frustration here is it does indeed seem to be a demon haunted world and too many equine charities are talking nonsense on the basis of false information,

Here is my latest information proving there is no reliable test for ragwort poisoning, complete with references, including one to the Nature paper I mention above.

Ragwort poisoning no test can confirm ragwort poisoning 100% (ragwortfacts.com)

Pembroke Council Ragwort bungling from an officer.

 One of the most important rules of logical thinking is, “don’t listen to authority look at the evidence.” Indeed there is abundant evidence in the medical literature that authoritarian behaviour is linked to poor ability and intelligence.

This is a classic example of a phenomenon I have noticed many times. Bureaucrats in local and even central government often don’t know their subjects well.

It  is a case from about a decade ago from Pembroke Council in Wales but it is still relevant today as the same issues happen. These are some quotes from an email concerning a developer who wanted, quite properly, to include ragwort in a nature area.

This starts with a falsehood.

2. The Council’s Landscape Officer comments: “It is strange to go to special levels to include Ragwort into the proposals when it is a notifiable weed elsewhere,

I don’t know what is precisely meant by “elsewhere,” but there has never, ever been such a thing as a notifiable weed in Wales or in the rest of Great Britain. There is no legal requirement for anyone to notify any authority of the presence of any plant.

Then there is more incorrect information!

and an offense [sic] to allow it to spread. So whilst the developer can include it, he will be obliged to remove it before it comes into seed.

This is nonsense! The law most emphatically, does not say that. You may be given a rare order to control ragwort but in the absence of an order there is no requirement to do anything at all.

I would suggest that we are aiming to set something up that is realistically impractical and may cause legal challenge if left un-managed. The Cinabar [sic] Moth is not a protected species but is an LBAP species and hence its suggested inclusion in the scheme.

The main issue with ragwort hysteria isn’t the Cinnabar Moth but all the other wildlife and the impact on the environment of the agricultural intensification created by the problem

There is more nonsense

However it is relatively common, and the plant itself is poisonous to humans although large quantities would have to be consumed to be lethal. However, inclusion in the scheme might lead to concern from more informed parents and I therefore question the overall wisdom of its inclusion in the play area.

Remember this is coming from a landscape officer someone who you might expect to know something about plants. Surely you would expect them to know that toxic plants are common in gardening, things like daffodils and bluebells. This is what truly informed parents should know. Yes there is a problem with ignoramuses and ragwort but that should be dealt with by educating them.

This sort of ignorance is by no means unusual from council officers. I actually started all this work when decades ago a council officer was determined that ragwort should be treated as an invasive species even though I impressed upon her that it was an ecologically important native. It got written into an official document afterwards that it was a foreign invader. It had to be complained about!

Another issue occurred years ago, when I was trying to conserve one of the best butterfly sites in the UK. A small 20 acre site in Wales with as many butterfly species as the entire English county of Essex! One of the tactics was to protect the trees. A council Tree Officer visited and tried to impress me with scientific names, only they were the wrong ones! Also he made one of the most ignorant statements I’ve ever heard from someone who should have understanding of ecology!

“If it were to be ploughed up everything would come back because the seeds would still be in the ground.”

The moral of this story is don’t listen to officials, find out the rules for yourself and be particularly sceptical of council officers and their claims.

Cornwall Council's ragwort balderdash.

During a conversation on twitter some ill-informed person held up Cornwall Council as a useful source of information on ragwort.

Nothing could be further from the truth as evidence by this piece of ignorant balderdash in their Highway Maintenance Manual

C.8 Specialist inspection of noxious and invasive Weeds

The control of injurious and noxious weeds is a statutory responsibility for

authorities under the Weeds Act 1959 and the Wildlife and Countryside Act 1981.

The primary objective of the specialist inspection is therefore to identify

areas of prescribed weeds that may be hazardous to users of the highway.

The prescribed weeds are:

Ragwort

Broad leaved dock

Curled dock

Creeping thistle

Spear thistle

First of all neither piece of legislation creates ANY statutory responsibility on local authorities. Then we get the nonsense that there has to be inspection to removed weed that may be hazardous to users of the highway. You can imagine it dock leaves causing car crashes by their mere presence on a verge! What utter nonsense! I suspect it is because they don't understand that Injurious weeds means harmful to the agriculture we had in 1920 when they were first written into the legislation governing Great Britain. They seem to  think that the term, "injurious weeds"  means that edible dock leaves are a danger to people and cause injury which is not the correct use of the word  injurious in this context.

Then there is the fact that none of these native plants is mentioned in the Wildlife and Countryside Act at all! The list there is of problematic foreign plants which are a problem and while there is a brief mention of Japanese Knotweed later on they don't cover these!

Some years ago Cornwall council was spending £100,000 a year on this kind of environmentally damaging control, which is a matter for concern and no doubt writing this sort of rubbish in documents helps the highway's department justify this.

The main message here is that local council officers very rarely know what they are talking about with regards to weeds so don't rely on them to inform yourselves!

 .

British Horse Society, Defra, Prof Derek knottenbelt laughing stock to scientists.

I recently returned from attending a scientific symposium in the English language in the Netherlands. It was a very very enjoyable experience. I was primarily there to listen and learn. There is always more to learn about this subject even after more than two decades of detailed study and it was fascinating

However, being British there were a few things I could help with during discussions. At one point one of the scientists put up on the screen a newspaper article in Dutch mentioning the old false story, from the British Horse Society, that 6,500 horses were dying a year in the UK of ragwort poisoning. As I have mentioned before I am learning Dutch and I have a bit knack for languages so I could read at least some of it.

During the question session after that talk I explained how this figure was calculated. They contacted many many equine vets, they didn't check to see if more than one vet in a practice responded so there may have been duplicate cases, they talked about confirmed cases when there isn't a test that can confirm them, and they got a tiny number of responses, just a handful in percentage terms without looking it up I think it was 4%..  Then they multiplied that figure as if everyone had answered! 

Of course I got a laugh! Professional scientists know how to treat data and this is obvious fakery. Yet this crooked and fraudulent science has informed public and political opinion.

There was a discussion session at the end and DEFRA the government department  that covers part of the UK came up. So I explained, "DEFRA get their risk statistics from the man who said it (ragwort) is poisoning the Cinnabar Moth."

It got another laugh! Of course, it is nonsense but the man who said it has been influencing government.

Ragwort is the main foodplant of the moth and as we had been told earlier in a fascinating talk it needs the alkaloids in the plant for the adult moth to find the plant and lay its eggs and for the caterpillars to be stimulated to eat! 

As I have said before Professor Derek Knottenbelt is the person behind this story and it is beyond ludicrous. It is nuttier than squirrel droppings!. Here is the quote from a horse care book.

`I would not normally advocate the eradication of any species, but this one has nothing to offer. I don't accept that eradicating ragwort would eradicate the Cinnabar Moth, which feeds on it. Ragwort is burgeoning and the Cinnabar is declining. In fact, I believe it is being poisoned. The moth was common throughout the years that ragwort was rare and now that ragwort is widespread, Cinnabar Moths are difficult to find. If we care about the moth, we have to find out why its population is declining in the face of an ad lib supply of "feed'.

I have an entire section of my ragwort facts website devoted to this man's strange beliefs. I would direct people to start with this article  There are no fewer than SEVENTEEN false or suspect claims there. Yet he has been promoted by the anti-ragwort brigade as a world leading expert. 

https://www.ragwortfacts.com/professor-derek-knottenbelt-country-illustrated.html

What if a vet tells you its ragwort poisoning?

 I am entering my third decade of studying ragwort this year so I thought to make a new posting illustrating why I believe that people should not necessarily believe that a veterinary diagnosis of ragwort poisoning is a correct one and why I can prove that hysteria exists and that it plays a part in some of the poor diagnoses that we do see.

I have over 1200 followers on twitter and a number of them are academics working in ecological areas. There are several professors there. These are not people who have been fooled by poor science. The ragwort issue is bedevilled by falsehoods and even made up nonsense. I can and have solidly proved it. People with the requisite level of education can see this and listen to me as a result.

The first thing I would say is that nobody, no vet , nobody can be sure of ragwort poisoning.

I am prompted to write my honest opinions here, as I often am, by something that someone said on twitter about a vet being sure that a ragwort poisoning was likely.

No one can be sure after the poisoning has occurred unless they poisoned the animal themselves.  This is because there is no test that can distinguish it from poisonings by other substances. most notably toxins from invisible moulds in feed like hay.

The first point to make about this is that it isn't me who says this. It comes from several veterinary textbooks written by world renowned veterinary professors, who have said this on the basis of the evidence. It is vital to remember in science that it is the evidence that counts not who says it.  but I think we can be pretty sure that modern university level veterinary textbooks will be correct.

 I have gone further than this of course. I am not going to baffle the readers of this blog with a complex explanation of what the biochemistry says, but in essence, it says that the compounds concerned have the same effect because they react with DNA molecules in the same way causing the same effects at a submicroscopic level. We know this to be true not from the authority of experts but from the much better authority of the biochemical evidence. 

You can read more on my website here, https://www.ragwortfacts.com/ragwort-poisoning-no-test-can-confirm-ragwort-poisoning.html

I have actually gathered more sources and more information, which I have yet to add to that page.

The other interesting point is that I didn't discover this initially for myself, My first port of call all that time ago was of course veterinary text books. I didn't discover this because in wasn't in the text books that I read at that time. It may be this that stops vets taking it into account as it seems they weren't trained to look for it. It is we know a more modern discovery. It was the case that at one time that  it was believed that Pyrrolizidine Alkaloids the toxic chemicals present in ragwort had a definitive microscopic test but  even this was only first published in the literature in the 1950s. I found out about this because a colleague attended a meeting where a researcher and veterinary professor was speaking and asked him if there was anything else which produced those signs and was told there was.. I then gathered information from the scientific literature to explain this.

I don't blog often but it is worth reading my previous entry here from last summer where I go into a bit more detail about this and describe an encounter with an equine vet who just did not know the subject thoroughly at all and is likely as a result misdiagnosing cases. Equine vet gets it wrong on ragwort. 

I will however restate a quote I made there from the latest scientific research which shows that ragwort poisoning is not as common as has been believed.

"Outbreaks of hepatic disease are common and once often were suspected to be caused by pyrrolizidine alkaloid (PA) toxicosis,  although more recent evidence suggests that PA toxicity is far less common than generally suspected."

Ragwort is often said to to be the cause without proper investigation anyway, even before investigation was possible.

One of the people who helps me with my research sent me an article from 1947 before we had the idea of microscopic examination confirming things, which subsequently was proved to be false anyway. It was  in an Irish newspaper. One farmer was suing another who had sold him a horse saying it was in good health when it wasn't. It died shortly afterwards from what the article calls "Cirhosis of the Liver", which is a reasonable description I suppose.

The vet who had made the diagnosis was asked by the judge. "What is the predisposing cause?"

and the vet was reported as responding.

"In some places it is put down to ragwort poisoning. Mouldy hay often cases it. Ragwort is usually put down for it."

This is still happening. There are all sorts of cases being reported in the media. One Equine charity started using four letter insults to me on Twitter when I told them you cannot diagnose ragwort poisoning from blood tests. It is pretty obvious that this abusive and ignorant person had been led to believe that falsehood by a vet as they insisted they had veterinary reports.

Equine charities have played a part in this as I document frequently here. I am going to be blunt and honest about it, but my opinions are based on a detailed study of the evidence.  The British Horse Society published an inflammatory article scaring people with a false story about a vet turning up and diagnosing ragwort poisoning on the spot without tests! What is more they used it to persuade people to fill in one of their infamous surveys. I'll say it clearly this is another example where the British Horse Society have used crooked methods to rig surveys or present their arguments in a false way.

If you want to survey people honestly you must not make leading statements which will bias the results. So giving people false information which overstated the risk from ragwort biased the results. The first question in the survey also made a false exaggerated claim of toxicity of the plant.

I keep saying this I know but this blog entry is going to new people I hope. The video below is from the excellent BBC comedy, Yes Prime Minister where  the infamously scheming Sir Humphrey Appleby explains exactly how you rig a survey using leading questions. 

This is exactly what the British Horse Society did! Of course it is a different subject but they rigged it in exactly the same way, with leading questions that shape the opinions of the person answering.

There is also a problem with  Defra who are claiming on their website that following advice will help you avoid fines under the Weeds Act, whilst lying by omission. The omission is that you cannot just be fined for not following their advice. You have to be ordered to something by a rare legal order and only then can you be fined and only then can you be fined if you don't comply.

The you have their Code of Practice declared, "out of date" and withdrawn legally some years ago  but still offered as advice . It is based on a bizarre and crazy use of risk statistics from a notorious source who claims that an animal that uses ragwort as its near exclusive food source is being poisoned by it and that animals won't  be affected by having their habitat destroyed!  See https://ragwortfacts.com/defra-ragwort-code-of-practice.html