EstherHegt
Well-Known Member
Wow I looked for a moment at this discussion, , it is read 12,847 times, that is very much and only a handfull writers did respond ;-) I didn't wrote anonymous and have peer reviewed publications backup for what I wrote.
ragwort I have had it with the myths
- Thread starter EstherHegt
- Start date
Alec Swan
...
Peer reviewed? By who? Your peers? They, as you, have little to recommend them. Your attempts to belittle and denigrate a world respected research scientist, was a very silly and basic mistake on your part.
Alec.
smokey
Well-Known Member
Myths eh
Pumas love ragwort, it's like catnip to them. They seek it out on windy nights so it's easier to inhale.
Once the pumas have 'gorged' themselves with ragwort they become very sociable and spend the rest of the night plaiting horses manes (not very well obviously, big paws)
Unfortunately long term ragwort abuse leaves pumas photophobic, which is why you never see them in daylight.
Love it, I guess that's why they have yellow eyes then!
EstherHegt
Well-Known Member
Alec, I don't think you have read any of our website. This page is about how a PA intoxication works. Knottenbelt is not somebody who had publications about ragwort and toxocologie, it his his opininion, he is also not named in the EFSA report as a source. I can understand that you can't believe that, but there is worldwide a lot of peer reviewed information, look at pub med etc. I give one more time some sources we used, and we have a lot of advisors and co authors. Some are also named in the EFSA journal, I gave that link before. European Food Safety Authority. 2007. Opinion of the Scientific Panel on contaminants in the food chain on a request from the European Commission related to Pyrrolizidine alkaloids as undesirable substances in animal feed. The EFSA Journal 447: 1-51.
Look at this page, maybe you can see than what I am writing http://www.ragwort.org.uk/background-info/7-i/11-ragwort-poisoning-how-does-it-work
and the peer reviewed literature we used for this article about how ragwort posioning works.
References:
(1) Schneider, D. 1987. The strange fate of pyrrolizidine alkaloids. In: Chapman, R. F., E. A. Bernays & J. G. Stoffolano (Eds.). Perspectives in
chemoreception and behavior: Springer, Berlin/Heidenberg. 123-142.
(2) Boppré, M. 1986. Insects pharmacophagously utilizing defensive plant chemicals (pyrrolizidine alkaloids). Naturwissenschaften 73: 17-26.
(3) Macel, M. 2003. On the evolution of the diversity of pyrrolizidine alkaloids. The role of insects as selective forces. Thesis Leiden University.
4) Giles, C. J. 1983. Outbreak of ragwort (_Senecio jacobaea_) poisoning in horses. Equine Veterinary Journal 15: 248-250.
(5) De Lanux-Van Gorder, V. 2000. Tansy ragwort poisoning in a horse in southern Ontario. Can. Vet. J. 41: 409- 410.
(6) Gardner, D. R., M. S. Thorne, R. J. Molyneux, J. A. Pfister & A. A. Seawrigh. 2006. Pyrrolizidine alkaloids in _Senecio madagascariensis_ from
Australia and Hawaii and assessment of possible livestock poisoning. Biochemical Systematics and Ecology 34: 736-744
(7) European Food Safety Authority. 2007. Opinion of the Scientific Panel on contaminants in the food chain on a request from the European Commission
related to Pyrrolizidine alkaloids as undesirable substances in animal feed. The EFSA Journal 447: 1-51.
(8) Bain, J. F. 1991. The biology of Canadian weeds. 96. _Senecio jacobaea_ L. Canadian Journal of Plant Science. 71: 127-140.
(9) Poole, A. L. & D. Cairns. 1940. Botanical aspects of Ragwort (_Senecio jacobaea L_.) control. Department of Scientific and Industrial Research
Bulletin 82: 2-61.
(10) Harper, J. L. & W. A. Wood. 1957. _Senecio jacobaea L_. The Journal of Ecology 45: 617-637.
(11) Cosyns, E. 2004. Ungulate seed dispersal. Aspects of endozoochory in a semi-natural landscape. Institute of Nature Conservation, Brussels.
(12) Dean R. E. & A. H. Winward. 1974. An investigation into the possibility of tansy ragwort poisoning of black- tailed deer. Journal of Wildlife
Diseases 10: 166-169.
(13) Candrian, U., J. Luthy, P. Schmid, Ch. Schlatter & E. Gallasz. 1984. Stability of pyrrolizidine alkaloids in hay and silage. J. Agric. Food Chem.
39: 930-933
(14) Goeger, D. E., P. R. Cheeke, J. A. Schmitz & D. R. Buhler. 1982. Toxicity of tansy ragwort (_Senecio jacobaea_) to goats. Am. J. Vet. Res.
43: 252-254.
(15) Molyneux R. J., Johnson, A. E.& L. D. Stuart. 1988. Delayed manifestation of Senecio-induced pyrrolizidine alkaloidosis in cattle: case
reports. Vet. Hum. Toxicol. 30: 201-205.
(16) Craig, A. M., E. G. Pearson, C. Meyer & J. A. Schmitz. 1991. Serum liver enzyme and histopathologic changes in calves with chronic and
chronic-delayed _Senecio jacobaea_ toxicosis. Am. J. Vet. Res. 52: 1969-1978.
(17) Odriozola, E., C. Campero, A. Casaro,T. Lopez, G. Olivieri & O. Melucci. 1994. Pyrrolizidine alkaloidosis in Argentinan cattle caused by
_Senecio selloi_. Vet. Hum. Tox. 36: 205-208.
(18) Johnson, A. E. & R. A. Smart 1983. Effects on cattle and their calves of tansy ragwort (_Senecio jacobaea_) fed in early gestation. Am. J. Vet.
Res. 44: 1215-1219
(19) Tilt, S.E. 1969. Ragwort toxicosis in a heifer. Can. Vet. J. 10: 302-306.
(20) Durham A. E., J. R. Newton,K. C. Smith, M. H. Hillyer, L. L. Hillyer, M. R. Smith, & C. M. Marr. 2003. Retrospective analysis of historical,
clinical, ultrasonographic, serum biochemical and haematological data in prognostic evaluation of equine liver disease. Equine Vet. J. 35: 542-547.
(21) DEFRA/AHT/BEVA. 2004. Department for Environment, Food and Rural Affairs Engeland. Equine Quarterly Disease Surveillance Report. Pilot Issue:
Focus on equine liver disease 7-9.
(22) Vos, J. H., A. A. J. Geerts, J. W. Borgers, M. H. Mars, J. A. M. Muskens & L. A. van Wuijckhuise-Sjouke. 2002. Jacobskruiskruid: bedrieglijke
schoonheid. Tijdschr. Diergeneesk. 127: 753-756.
(23) 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.
(24) Stewart, M. J. & V. Steenkamp. 2001. Pyrrolizidine poisoning: a neglected area in human toxicology. Therapeutic Drug Monitoring 23: 698-708
(25) Chojkier, M. 2003. Hepatic sinusoidal-obstruction syndrome: toxicity of pyrrolizidine alkaloids. Journal of Hepatology 39: 437-446.
(26) Czaja, M. 1998. Liver growth growth and repair. Chapman en Hall London. ISBN 0412 71260.
(27) Lessard, P., W. D. Wilson, H. J. Olander, Q. R. Rogers, & V. E. Mendel. 1986. Clinicopathologic study of horses surviving pyrrolizidine alkaloid
(Senecio vulgaris) toxicosis. Am. J. Vet. Res. 47: 1776-1780.
(28) Roeder, E. & Pflueger, T. (1995). Analysis of pyrrolizidine alkaloids: a competitive enzyme-linked immunoassay (ELISA) for the quantitative
determination of some toxic pyrrolizidine alkaloids. Nat. Toxins 3:305-309.
TrasaM
Well-Known Member
this discussion is just like ragworth.. You think it's gone but a week later it's back again. So what's the bottom line? Is it or is it not poisonous?
s4sugar
Well-Known Member
I haven't read your website but I have seen a horse (not mine) pts through eating ragwort in hay.
I will continue to remove any ragwort from my land and walked five acres today -removing just seven plants and spraying Roundup onto the roots. It has taken twenty years to get down single figures and I doubt I will ever eradicate it as on nearby council land it is unchecked.
I would love to see it become extinct here. The cinnabar moth can now be found around the world having been introduced to eat the noxious weed so it can live on abroad.
I will continue to remove any ragwort from my land and walked five acres today -removing just seven plants and spraying Roundup onto the roots. It has taken twenty years to get down single figures and I doubt I will ever eradicate it as on nearby council land it is unchecked.
I would love to see it become extinct here. The cinnabar moth can now be found around the world having been introduced to eat the noxious weed so it can live on abroad.
pootleperkin
Well-Known Member
Look Esther, we get it:
Ragwort is poisonous to different species at different levels.
If horses eat it little and often, then large scale liver necrosis is not caused, the liver will probably be compensated in one way or another and the horse will probably be ok.
If the horse eats lots of ragwort, then it might not be ok, as the liver will likely fail.
You are worried that we conclude that horses that have some sort of liver disease are mistakenly diagnosed with chronic ragwort poisoning, when you think they probably do not.
You think that the latter cases cause 'hysteria' about ragwort poisoning in the UK and that we believe in myths.
It doesn't.
We don't need to know all of the in's and out's of the poisoning process - it is irrelevant to how we responsible horse owners manage our fields, 'cos we just eliminate the risk! It's like talking about skin cancer to sunbed users - yes, the specialist wants to know how it is caused by such and such a pathway causing mutation of x and x.... but all the patient needs to know is that they shouldn't go on sunbeds as that is what causes the risk!!
We know ragwort isn't good for any of our stock because of the underlying risk. It grows like wildfire over here due to the way the rural areas of the country are (or more usually, are not) managed. It is impossible to tell if your animals eat it or not (though I know, not likely) if it is present in grazing land, so those of us who can look after our own pasture don't like to take the risk and kill it.
Case closed. No hysteria. No myths that need to be dispelled. You are preaching to the converted. No need to keep banging on about Knottenbelt.
Ragwort is poisonous to different species at different levels.
If horses eat it little and often, then large scale liver necrosis is not caused, the liver will probably be compensated in one way or another and the horse will probably be ok.
If the horse eats lots of ragwort, then it might not be ok, as the liver will likely fail.
You are worried that we conclude that horses that have some sort of liver disease are mistakenly diagnosed with chronic ragwort poisoning, when you think they probably do not.
You think that the latter cases cause 'hysteria' about ragwort poisoning in the UK and that we believe in myths.
It doesn't.
We don't need to know all of the in's and out's of the poisoning process - it is irrelevant to how we responsible horse owners manage our fields, 'cos we just eliminate the risk! It's like talking about skin cancer to sunbed users - yes, the specialist wants to know how it is caused by such and such a pathway causing mutation of x and x.... but all the patient needs to know is that they shouldn't go on sunbeds as that is what causes the risk!!
We know ragwort isn't good for any of our stock because of the underlying risk. It grows like wildfire over here due to the way the rural areas of the country are (or more usually, are not) managed. It is impossible to tell if your animals eat it or not (though I know, not likely) if it is present in grazing land, so those of us who can look after our own pasture don't like to take the risk and kill it.
Case closed. No hysteria. No myths that need to be dispelled. You are preaching to the converted. No need to keep banging on about Knottenbelt.
Kallibear
Well-Known Member
10pages later (40 depending on your settings 
) and I STILL don't get the point of this thread???! Is it just me?! 
So far the only thing that's been established (apart from EstherHegt and co being a bit weird, with a vendetta against Proffesor Knottenbelt) is that ragwort is bad for horses.
I knew that before I opened the thread a couple of weeks ago?!!
) and I STILL don't get the point of this thread???! Is it just me?! So far the only thing that's been established (apart from EstherHegt and co being a bit weird, with a vendetta against Proffesor Knottenbelt) is that ragwort is bad for horses.
I knew that before I opened the thread a couple of weeks ago?!!
Moomin1
Well-Known Member
I don't know the point in this entire conversation, because we all know that ragwort does (and I personally see it very often) pose a risk to horses. Often it goes unnoticed through lack of symptoms (much like alcoholic liver damage) until it is very advanced. Ten horses removed from sparse pasture over a year ago - ALL had varying stages of liver disease, ranging from a very cautious prognosis to a very hopeful one. Nevertheless, every one of them had liver damage due to being on sparse grazing with an average amount of ragwort, which the owner maintained he 'treated' each year. He clearly didn't. Some of these horses were emaciated or in very poor condition, others in ok condition. The ones who had mild liver damage had only been on the pasture for approx one year. Those horses appeared perfectly healthy on the outside, and it was only routine bloods which revealed the liver damage. The ones who were badly damaged were emaciated, with extensive alopecia and anaemia, and they had been on the land approx 4-5 years.
Tnavas
Well-Known Member
Ragwort is a slow accumulative poison. Humans can be affected by the juices of ragwort pulled with bare hands.
Horses do eat it when it is alive and fresh when there is insufficient grazing available.
Horses that eat it in hay suffer - have seen it at one place I worked at - we had to spread out every slice of hay and check it for ragwort after several horses got sick.
Sheep do eat the plant but only in the small rosette stage - here in NZ in sheep country you rarely see ragwort because the sheep eat it when it is small. In the Dairy areas though ragwort grows to large plants.
I think the governments have plenty of research on their side - if it is against the law to have Ragwort then it must have been proven to be a problem
It is sad that the Cinnebar moth likes to live off ragwort but as ragwort wasn't introduced to UK until 1690 the moth is also not a native to UK. The moth has also been introduced to NZ to help control the weed.
Ragwort has no purpose and reduces grazing availability
The plant is a pain in the butt weed and any sensible person will ensure its safe and permenant removal from their paddocks.
Last edited:
Tnavas
Well-Known Member
NO definately not - just total common sense approach - if it is poisonous - remove it!
PS - I'm originally from UK and in the early 60's we were advised then to pull up the ragwort. - Nothing has changed!
To be honest I think you are more hysterical about Ragwort than the whole HH community. This is not the first time you have been on this site spouting the same information.
Last edited:
Tnavas
Well-Known Member
Regarding the 'ragwort video', I've never taken such measures when pulling ragwort and I don't know anyone who does.
When spraying toxic herbicides as shown in the video it may well be a recommendation to wear protective clothing.
I'd rather err on the side of caution where ragwort is concerned, not through hysteria or inaccuracies, but because I value my horse and would rather not take the risk, whether exaggerated or not.
Pregnant women were once told that an anti sickness drug called thalidamide was safe to take, and look how that turned out.
The video was hilarious - if it was taken to protect the person from Ragwort
BUT
perfectly sensible if protecting yourself from the herbaside.
My old boss of many years ago ended up in hospital with what appeared to be a heart attack yet there was no signs that would have been expected in his blood tests for a heart attack. Further tests revealed high levels of various chemicals used on the fruit orchard he owned. He had always worn protective clothing and the tractor with the booms on it was covered when spraying. Despite the precautions he still had a very dangerous reaction.
Something that was said to me many years ago
"You don't have to find out everything by personal experience!" Other people have lost horses from eating Ragwort - I don't need mine to die to understand that it is best got rid of.
hairycob
Well-Known Member
I'm still confused about what we are meant to change. I have asked twice & not had an answer.
For the timebeing, at this time of year, I shall continue to spend a few minutes each day clearing ragwort from my winter field. Summer field luckily only gets a couple of plants a year that get dug up as soon as I spot them.
For the timebeing, at this time of year, I shall continue to spend a few minutes each day clearing ragwort from my winter field. Summer field luckily only gets a couple of plants a year that get dug up as soon as I spot them.
Tnavas
Well-Known Member
Hi Hairy cob - someones awake in UK - I'm not sure either what we are meant to do either!
Just read that ragwort when grazed can become an annual plant so flowering in the first year.
I shall continue to pull the 'Evil Yellow One' from my pasture.
Just read that ragwort when grazed can become an annual plant so flowering in the first year.
I shall continue to pull the 'Evil Yellow One' from my pasture.
Fellewell
Well-Known Member
Love it, I guess that's why they have yellow eyes then!
That'll be the liver damage, if pumas didn't love ragwort so much we'd be falling over them
There's lots of info on ragwort in the kids section of Jul/Aug BHS mag. What's Esther going to say about us indoctrinating our children
(another website link I shouldn't wonder)hest
Well-Known Member
Have sat on my hands long enough.
I don't often get involved in threads like this, but this one shows academia at its worst:
A group of researchers appear to be attempting to besmirch the work of another peer under the thinly-veiled guise of 'helping' the horsey public and doing them all a favour by 're-educating' them for once and all about ragwort.
Allegations of a smear-campaign are defended by the 'here are the references, you can't argue with them' approach. Cue long lists of sources, most of which are very old (and surely therefore obselete, particularly in scientific research).
You are entitled to your opinion so, if I were in Dutch shoes (or should that be clogs), I would stick to questioning Prof K's published research (but not annecdotal evidence) in peer-reviewed articles.
Yes, I would also challenge him politely during 'any questions' at conferences or seminars if I felt the need.
But linking him to myths and hysteria in this back-handed manner on a forum is highly unprofessional IMO and, if you any of you are chasing funding at the moment, you may find that this sort of approach is not doing any of you any favours in the long run.
I don't often get involved in threads like this, but this one shows academia at its worst:
A group of researchers appear to be attempting to besmirch the work of another peer under the thinly-veiled guise of 'helping' the horsey public and doing them all a favour by 're-educating' them for once and all about ragwort.
Allegations of a smear-campaign are defended by the 'here are the references, you can't argue with them' approach. Cue long lists of sources, most of which are very old (and surely therefore obselete, particularly in scientific research).
You are entitled to your opinion so, if I were in Dutch shoes (or should that be clogs), I would stick to questioning Prof K's published research (but not annecdotal evidence) in peer-reviewed articles.
Yes, I would also challenge him politely during 'any questions' at conferences or seminars if I felt the need.
But linking him to myths and hysteria in this back-handed manner on a forum is highly unprofessional IMO and, if you any of you are chasing funding at the moment, you may find that this sort of approach is not doing any of you any favours in the long run.
pootleperkin
Well-Known Member
Exactly my thoughts Hest - loved the way Esther listed an arms length list of references to back up her 'peer review' papers - however, the point was that we were talking about her group's *new* peer review research, not the literature in general.
It seems their group are running with their own agenda, trying to put a spin on a subject which has, in terms of risk management, essentially been put to bed, in the hope of keeping funding going.
As said before, if they want to continue in this vein, then they need to see if they can keep publishing and presenting their message at conferences, not banging on about it here. I'm guessing Esther is working on her doctorate - I just hope that she hasn't been lead astray too far by her supervisors and become too polemic.
It seems their group are running with their own agenda, trying to put a spin on a subject which has, in terms of risk management, essentially been put to bed, in the hope of keeping funding going.
As said before, if they want to continue in this vein, then they need to see if they can keep publishing and presenting their message at conferences, not banging on about it here. I'm guessing Esther is working on her doctorate - I just hope that she hasn't been lead astray too far by her supervisors and become too polemic.
Last edited:
Dirtymare
Well-Known Member
This is very well written. I totally agree.
hest
Well-Known Member
If Ester is indeed working on her doctorate then I hope for her sake that no one on her viva panel is a friend or associate of Prof K
pootleperkin
Well-Known Member
Hest, I'm guessing that as in most of Europe, that if she is doing her doctorate, she won't have a viva with two opponents, but an open, public defence of her thesis. Should we give the Prof. the nod to go across and watch? Anyone can join in with the questioning 
hest
Well-Known Member
Hest, I'm guessing that as in most of Europe, that if she is doing her doctorate, she won't have a viva with two opponents, but an open, public defence of her thesis. Should we give the Prof. the nod to go across and watch? Anyone can join in with the questioning
LOL!
If he's busy, Rhino could go in his place - there's no flies on her!
Circe
Well-Known Member
Love it, I guess that's why they have yellow eyes then!
Yes, unfortunately most pumas have bad jaundice from the liver damage caused by the ragwort. Its very sad.
Kx
hairycob
Well-Known Member
Just had a quick look again at the list of peer reviewed papers & I'm pretty sure, that along with most horse owners, I will have them in that big pile of "must reads" by the side of my bed. I really must get round to reading them sometime - trouble is I won't have time until after I have perfected my PSG tests & am jumping 1.30 tracks.
pootleperkin
Well-Known Member
RagwortFacts
New User
As someone who has lurked through this thread and who has been studying ragwort for many years I just have to come in here. I am shocked at the level of ignorance, the bad thinking and illogical statements and the level of toxic, xenophobic bullying.
I too come from a nation where English is not the native language and this kind of thing should simply not be acceptable to decent people.
Esther said there were a lot of myths and there are! This thread shows people repeating them and repeating them time and time again.
Let's be clear about this one. It has been looked at by one of the greatest experts on ragwort in the world. He actually has a Phd specifically on this plant, Dr Pieter Pelser and this is what he wrote with Dutch expert Esther Hegt.
"Through our research about the sources of the reports on the danger of touching ragwort, we conclude that there is no substantial evidence that there is a health risk for people. The amount of pyrrolizidine alkaloids that might be absorbed through the skin is very low and there is no proof that these alkaloids are being changed into a toxic form."
All sorts of things might be claimed. Someone might claim there is a teapot in orbit around the moon, but we do not accept things in science without evidence.
The experts on the biochemistry of ragwort, whose work I have read seem to entirely confirm the statement by these two experts.
Just because somone in the government says something doesn't mean it is true. That argument is very bad thinking and is an example of one of the oldest and best known logical fallacies, "Arguement from Authority". It is also the case that it is a myth that ragwort is against the law in the UK.
Last year a British Horse Society joint leaflet was stopped by the Advertising Standards Authority (ASA) for making a similar kind of claim.
This is another myth. . Both the Cinnabar Moth and Ragwort are native species in the UK.
The ecological issues aren't mainly about the Cinnabar Moth anyway and we have seen a crowd of people queueing up to demonstrate a complete lack of understanding of ecology.
The truth is that there are many myths about ragwort and they have led when repeated to the the ASA acting. The ASA do not have a particular axe to grind they just insist that advertisers must have proof for their claims.
So companies advertising thousands of horse deaths must have evidence. They didn't so they have had to stop making the claims.
I will give you some evidence. If you make a Freedom of Information Request to Liverpool University and ask them about liver damage and horse deaths. This is the kind of information you will get. Over the 5 year period 2006-2010 it seems they did indeed record a number of horses with liver disease, however it seems that they did not record a single example of it being due to ragwort poisoning. NOT ONE!
I'll give you a list of the myths here.Ragwort Myths
But unfortunately there are people who will still be "true believers" in them never how hard experts try to debunk them. It is rather like the people who believe in many daft ideas like 9/11 being a government conspiracy, or the Queen being a drug dealer, or a lizard in disguise. Some people will believe anything.
Esther Hegt is actually highly intelligent. She is well known as an expert in her own country. Her English isn't perfect, but frankly there seem to have been some rather rude people here who seem to have been feigning lack of comprehension just for effect.
rhino
Well-Known Member
Highly intelligent? Possibly, but she seems to be completely unable to answer simple questions put to her. As a result of this, I feel completely justified in not believing anything she says, as the oft requested 'evidence' is not forthcoming.
Lots of people are self proclaimed 'experts'. Generally it means nothing, other than they feel they can dictate to others how they should be thinking or acting.
Alec Swan
...
RagwortFacts, I don't suppose that with Esther, you have any collective experience of cats, do you? If you do, there's another stupid thread which would benefit from your input. Go on, give it a go, you'll fit in a treat!
Alec.
Alec.
smokey
Well-Known Member
Lol Alec!:
cptrayes
Well-Known Member
I object to this statement. The two non native speakers were warned politely many times that their less than fluent use of English phrases was unintentionally (at first) offensive to native speakers and they chose to continue to insult us with their use of our language. Many of us acknowledged how good their English was, but it was not good enough to come on a foreign language website and lecture the people of that country. Having been warned about the offence they were causing, they continued in the full knowledge of that offence, which is downright rude.
Not only that but they also chose to insult us by accusing us of not knowing how to manage our own pastures and our own horses.
They made repeated statements which were incorrect and others which could not be substantiated.
As for the rest of what you have written, it is, can we repeat for the umpteenth time
COMPLETELY IRRELEVENT.
Ragwort is poisonous.
We manage it fine.
There is no hysteria in this country though there has been plenty from Nick and Ester on this thread.
PLEASE go away and worry about something more imporant than ragwort in the UK, like why the Dutch have been so slow to implement the EU pig welfare standards.
Last edited:
rhino
Well-Known Member
Esther and co.
Can you prove conclusively that handling ragwort carries no risk? No.
Can you prove conclusively how many horses die in the UK per annum as a direct result of ragwort poisoning? No.
Polite suggestion; go away and find out. Get your results published. Then come back and we can actually have a reasonable discussion.
Until that point, no-one knows, and in that case I find it perfectly reasonable for horse owners to (a) prevent their stock coming into contact with it, and (b) take sensible precautions - eg. wearing gloves - when handling it.
Can you prove conclusively that handling ragwort carries no risk? No.
Can you prove conclusively how many horses die in the UK per annum as a direct result of ragwort poisoning? No.
Polite suggestion; go away and find out. Get your results published. Then come back and we can actually have a reasonable discussion.
Until that point, no-one knows, and in that case I find it perfectly reasonable for horse owners to (a) prevent their stock coming into contact with it, and (b) take sensible precautions - eg. wearing gloves - when handling it.