rhino
Well-Known Member
Let's try again
You claim that Prof Knottenbelt has categorically stated that he has research which proves that 1000 horses die per annum in the UK from Ragwort Toxicity.
Link me to this research. If I don't see it how can I know it ever happened?
The only source I can find for the figures is NOT research, and is clearly explained as an ESTIMATE and that figures MAY reach a certain level. This is not a myth; this is an opinion.
Is this the cause for your attempts to discredit him?
From Esther's website:
So Professor Knottenbelt's estimate of 500 could quite easily be correct?
Next point
You claim that the BHS produced a scientific study with erroneous extrapolation of results. Link me to this study, and also the ASA adjudication you repeatedly discuss. If I don't see it how can I know it ever happened? Who carried out the study? Was Professor Knottenbelt even involved or are you trying to implicate him in something he has no involvement with?
From Esther's website:
283 possible cases recorded by 4% of all the vets in the UK? Is it honestly conceivable that 4% of vets saw EACH and EVERY case of liver disease?
We will never know the true figures for ragwort toxicity. Heck, we don't even know how many horses there are in the UK! Estimates are all that anyone can do. Deliberate underestimations are not helpful and can be harmful. Do you honestly believe that the 13 or so horse deaths each year in the UK who are directly linked to Ragwort toxicity on pathology are the ONLY deaths in the UK caused by Ragwort?
Third point
The assertion that the toxic chemicals can be absorbed through the skin.
By Pieter Pelser
Lack of proof means something is unproven, not disproven. Nothing more.
Link me to this research. A transcript of his presentation in Parliament would be acceptable. If I don't see it how can I know it ever happened?
As far as I am aware he never claimed that he had carried out an 'experiment' by handling Ragwort, and to me the above is clearly an anecdote, which in itself has no scientific value but can be a useful stimulus to carry out real research. My understanding is that he became unwell after handling the plant, and liver function tests revealed liver damage. Of course he will not publish this, as he realises that anecdotes are NOT data.
Final point
On your previous reply to me you seem to suggest that Professor Knottenbelt has personally been involved in research on rats? Is this correct and can you link me to it please. If I don't see it how can I know it ever happened?
I think you were referring to this study by the 'rats' comment.
Brauchli J., J. Luthy, U. Zweifel & C. Schlatter. 1982. Pyrrolizidine alkaloids from Symphytum officinale L. and their percutaneous absorption in rats. Experientia (Basel) 38: 1085-1087.
Am I correct? Why did you claim that Professor Knottenbelt was directly involved?
Or does this research have nothing to do with Professor Knottenbelt directly and in fact was another attempt to obfuscate the discussion and tar the reputation of an eminent scientist?
You are repeatedly making claims, which you are either UNABLE or UNWILLING to show any proof for. Sorry, but for me your arguments are fundamentally flawed and entirely based on deliberate misunderstandings and reliance on hearsay.
Your problems with Professor Knottenbelt seem to stem directly from (a) an estimate of between 500 and 100 horse deaths per annum in the UK due to Ragwort toxicity, and (b) a personal anecdote of an occasion of him handling Ragwort and a subsequent liver function test.
Neither of which you can disprove in any way.
You claim that Prof Knottenbelt has categorically stated that he has research which proves that 1000 horses die per annum in the UK from Ragwort Toxicity.
Link me to this research. If I don't see it how can I know it ever happened?
The only source I can find for the figures is NOT research, and is clearly explained as an ESTIMATE and that figures MAY reach a certain level. This is not a myth; this is an opinion.
http://www.equinescienceupdate.co.uk/ragwort1.htmDr Derek Knottenbelt of the Liverpool University Veterinary School estimates that around 500 horses and ponies died of liver failure due to ragwort poisoning last year. With the increasingly widespread distribution of the plant, he suggests that this year the total number of equine deaths from ragwort poisoning may reach 1000. This is possibly an underestimate of the problem because the signs are not specific and many cases of ragwort poisoning are not diagnosed.
Is this the cause for your attempts to discredit him?
From Esther's website:
The exact number of victims of Ragwort poisoning is unknown. The symptoms of Ragwort poisoning cannot be distinguished from other liver disorders and poisoning can only be confirmed by means of a post-mortem liver exam. These exams are, however, not common practice, and reliable data on the number of victims are therefore not available. There could be more than hundreds of victims, but there could also be much fewer.
So Professor Knottenbelt's estimate of 500 could quite easily be correct?
Next point
You claim that the BHS produced a scientific study with erroneous extrapolation of results. Link me to this study, and also the ASA adjudication you repeatedly discuss. If I don't see it how can I know it ever happened? Who carried out the study? Was Professor Knottenbelt even involved or are you trying to implicate him in something he has no involvement with?
From Esther's website:
The only scientifically sound conclusion from this is that in 2002 283 horses presumably died of Ragwort poisoning. It is not known in how many of these cases a post mortem is performed.
283 possible cases recorded by 4% of all the vets in the UK? Is it honestly conceivable that 4% of vets saw EACH and EVERY case of liver disease?
We will never know the true figures for ragwort toxicity. Heck, we don't even know how many horses there are in the UK! Estimates are all that anyone can do. Deliberate underestimations are not helpful and can be harmful. Do you honestly believe that the 13 or so horse deaths each year in the UK who are directly linked to Ragwort toxicity on pathology are the ONLY deaths in the UK caused by Ragwort?
Third point
The assertion that the toxic chemicals can be absorbed through the skin.
By Pieter Pelser
(Bold added for emphasis)Report on the Internet by Dr. Knottenbelt (Liverpool University). This veterinarian is quoted on the internet quite a lot, because he stated, during a debate in the House of Commons, that the toxic substance in ragwort can almost certainly be absorbed through the skin. In response to this we contacted Dr. Knottenbelt. Through an email he informed us that there is no scientific proof for his statements. He writes that he himself has suffered liver damage after manually removing ragwort plants. The results of this 'experiment' have not been published and, according to us, are not obtained through a good scientific trial.
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
Lack of proof means something is unproven, not disproven. Nothing more.
Link me to this research. A transcript of his presentation in Parliament would be acceptable. If I don't see it how can I know it ever happened?
As far as I am aware he never claimed that he had carried out an 'experiment' by handling Ragwort, and to me the above is clearly an anecdote, which in itself has no scientific value but can be a useful stimulus to carry out real research. My understanding is that he became unwell after handling the plant, and liver function tests revealed liver damage. Of course he will not publish this, as he realises that anecdotes are NOT data.
Final point
On your previous reply to me you seem to suggest that Professor Knottenbelt has personally been involved in research on rats? Is this correct and can you link me to it please. If I don't see it how can I know it ever happened?
I think you were referring to this study by the 'rats' comment.
Brauchli J., J. Luthy, U. Zweifel & C. Schlatter. 1982. Pyrrolizidine alkaloids from Symphytum officinale L. and their percutaneous absorption in rats. Experientia (Basel) 38: 1085-1087.
Am I correct? Why did you claim that Professor Knottenbelt was directly involved?
What way did he 'prove' they could be passed through skin? Prove, not suggest, as we like facts here, not hearsay, don't we?
he shaved a rat and used a bearing ointment that is absorbed through the skin
Or does this research have nothing to do with Professor Knottenbelt directly and in fact was another attempt to obfuscate the discussion and tar the reputation of an eminent scientist?
You are repeatedly making claims, which you are either UNABLE or UNWILLING to show any proof for. Sorry, but for me your arguments are fundamentally flawed and entirely based on deliberate misunderstandings and reliance on hearsay.
Your problems with Professor Knottenbelt seem to stem directly from (a) an estimate of between 500 and 100 horse deaths per annum in the UK due to Ragwort toxicity, and (b) a personal anecdote of an occasion of him handling Ragwort and a subsequent liver function test.
Neither of which you can disprove in any way.