Post by jamshundred on May 5, 2015 16:12:38 GMT
There are two published responses to the Sheppy article in the current UK Bulletin, one from Duncan MacIntyre,
a veterinarian and long time Dexter breeder, who has served in leadership on the DCS council, and Veronica Schofield of the Moomin herd, also a long time respected breeder having served in leadership capacities.
These are prominent members of the UK Dexter breeding circles, and they did NOT have the benefit of detailed information showing the article was flawed with regard to two of the three bulls as to actual documented data.
The leadership of ADCA . . . . they DID have that information, and they chose to publish that article anyway, even when they were advised that Grinstead Plover was not the sole source of the color dun - as the earliest US dun animals did not descend from this bull, and they were given details on the markers of Parndon Bullfinch to show the information in the article was in error.
That ADCA chose to go ahead and publish that article as a means to discredit the bloodline preservation effort in the US, and to manipulate the ADCA membership in a crucial vote. . . .was not only unprofessional, it showed a marked lack of fundamental reasoning. It certainly did not fall within the definition of leadership!
ADCA owes an apology to their members. . . one and all.
Here are both responses .
Judy
a veterinarian and long time Dexter breeder, who has served in leadership on the DCS council, and Veronica Schofield of the Moomin herd, also a long time respected breeder having served in leadership capacities.
These are prominent members of the UK Dexter breeding circles, and they did NOT have the benefit of detailed information showing the article was flawed with regard to two of the three bulls as to actual documented data.
The leadership of ADCA . . . . they DID have that information, and they chose to publish that article anyway, even when they were advised that Grinstead Plover was not the sole source of the color dun - as the earliest US dun animals did not descend from this bull, and they were given details on the markers of Parndon Bullfinch to show the information in the article was in error.
That ADCA chose to go ahead and publish that article as a means to discredit the bloodline preservation effort in the US, and to manipulate the ADCA membership in a crucial vote. . . .was not only unprofessional, it showed a marked lack of fundamental reasoning. It certainly did not fall within the definition of leadership!
ADCA owes an apology to their members. . . one and all.
Here are both responses .
Judy
The use of modern genetic advances in the Dexter breed
During the last few decades the advances of our knowledge and
understanding of genetics has surpassed all expectations. From the most
basic understanding of how genetic instructions are carried in the cells of the
body and how these can be replicated to produce the next generation, we
have now the knowledge of the complete genetic pattern for man and some
animal species. We can identify individual components of this code, and map
out the normal, and from understanding the normal we can pick out the
abnormal. Instead of merely spotting when a genetic abnormality is expressed
by double inheritance of defective genes we can now produce relatively quick
and easy to use tests which can pick out individuals carrying particular genetic
codes, such as the chondrodysplasia gene so well recognised in the Dexter
breed. We can identify which animals carry red or dun but look black, which
produce A 1 or A2 milk, are homozygous polled or heterozygous polled. More
than this, if any previously unrecognised genetic defect is identified, we can,
with as few as 6 affected animals, identify the exact location of the genetic
defect and produce a test to identify carriers.
It was therefore with great sadness that I read "Introgression in Historic Dexter
Bulls" in the last issue of the Bulletin, purporting to show how the benefits of
modern genetic techniques can be applied to the Dexter breed. There was one
useful bit of information in the article, the reference to "Managing Breeds for a
Secure Future", a book written by DP Sponenberg and DE Bixby, published in
2007. Professor Sponenberg was hitherto unknown to me, but I learned that
he is now a member of the DCS team of Genetic Advisors, is a highly qualified
and respected authority in the USA, and I would commend his book to
everyone. Being interested in exactly what he says about "the standard three
test of Phenotype, history and genetic analysis" as quoted by Andrew Sheppy,
I purchased a copy of the book and have read it from cover to cover. It is
highly readable, requiring little specialist knowledge to understand, and is, in
short, a wonderful exposition of exactly what a breed is and what is needed to
keep it genetically healthy. I have begun, but not completed, an attempt to
purchase a number of copies for distribution in UK, and the first recipients
should be without a doubt, all our DCS council members.
An understanding of the dynamics of the genetic makeup of a breed lets us
understand the slow loss of genetic variability within a closed breed over a
period of time, and as an antidote to that the value of occasional added
genetic material. This added material may be in the form of "grading up" as an
official breed society policy, or it may happen by accident through mistaken
registration of outcrosses as purebred animals. In fact it matters little in the
longer term which happens, as long as the resulting offspring from any such
"impure" individuals are selected according to breed standards. Seven
generations down the line we have less than 1 of the genetic input of the
introduced genetics. Of course most of the 1 consists of genes common to
all cattle. The advantage to the breed is the replacement of some of the
genetic material lost in the course of closed breeding, which happens unseen
and unrecorded. It is interesting to note that one of the findings of the Cardiff
20
project was that the Dexter breed, though showing evidence of being very
much a distinct and identifiable breed, possessed a great degree of genetic
variability, the sign of a healthy breed.
In Andrew Sheppy's article on "Introgression in Historic Dexter Bulls" we find
him applying the three standard tests as suggested by Prof Sponenberg. But
let us look at the reliability of Andrew's evidence placed in each of the three
parts of the test. As far as the first "History" is concerned, in the first two
cases, we find Mr Sheppy relying on hearsay evidence, from family members
of deceased breeders. In the case of Charley Pudding he says "it was
admitted" and we have to ask, by whom, and would they have been in a
position to give such a statement. In the case of Shadwell Robert, the historic
evidence comes from alleged statements from a niece of the breeder. It is well
recognised by those with long experience of the breed, that the two sisters of
the family concerned had a very poor relationship and thus family
disagreements enter the arena and cloud the evidence. That accounts for the
historic evidence in the case of the first two bulls in the paper. For the third bull
in the paper, Grinstead Plover, the historic evidence is so flimsy that it enters
the realms of the fantasy world of the emperor's new clothes. We are expected
to believe that Lady Loder, one of the foremost and most respected breeders·
of her time, was either so deceitful, or so stupid, that she either ignored, or did
not notice, that a bull reared in her herd from a calf, was polled, at a time when
the whole herd was horned, no calves being dehorned. Worse still, Lady Loder
then sold the bull, and Beryl Rutherford, one of the most observant people I
have ever encountered, did not notice that a bull with no horns was being sold
from a horned herd, and that 50 of his calves were polled. The assumptions
made by Andrew Sheppy are a dreadful slur on the reputation of some of our
most significant and most respected influences on the breed. He also expects
us to believe that the dun colour, having entered the Red Poll breed when the
Suffolk Dun merged with the Norfolk Red, emerged in Grinstead Plover. What
Andrew does not tell us, is that the Suffolk Dun and the Norfolk Red merged in
the 1840's. How many generations do we go down from 1846 to 19667 With
the Red Poll breed selecting so strongly for both red and polled, it seems to
me that Mr Sheppy's version has little credibility. Moreover, there are recorded
dun Dexters on both sides of the Atlantic which are not descended from
Grinstead Plover.
For the future, given the biases and questionable conclusions of Mr Sheppy, I
would urge DCS Council to disregard him as a "genetic advisor", to
concentrate on advice from properly qualified geneticists, such as Professor
Sponenberg, and Prof. John Woolliams of the Roslin Insitute. Now that I think
on it, Dr John Woolliams was listed by our DCS council Chairman when I
pushed her to name the genetic advisors, though he does not appear on our
website as such. Please, DCS Council, consign the advice based on hearsay
and bias to the bin, concentrate on the advice of properly qualified
professionals, and, most importantly, READ PROFESSOR SPONENBERG
AND BIXBY'S BOOK. Council owe it to the Society they run to be better
informed.
Duncan Macintyre BVMS MRCVS
During the last few decades the advances of our knowledge and
understanding of genetics has surpassed all expectations. From the most
basic understanding of how genetic instructions are carried in the cells of the
body and how these can be replicated to produce the next generation, we
have now the knowledge of the complete genetic pattern for man and some
animal species. We can identify individual components of this code, and map
out the normal, and from understanding the normal we can pick out the
abnormal. Instead of merely spotting when a genetic abnormality is expressed
by double inheritance of defective genes we can now produce relatively quick
and easy to use tests which can pick out individuals carrying particular genetic
codes, such as the chondrodysplasia gene so well recognised in the Dexter
breed. We can identify which animals carry red or dun but look black, which
produce A 1 or A2 milk, are homozygous polled or heterozygous polled. More
than this, if any previously unrecognised genetic defect is identified, we can,
with as few as 6 affected animals, identify the exact location of the genetic
defect and produce a test to identify carriers.
It was therefore with great sadness that I read "Introgression in Historic Dexter
Bulls" in the last issue of the Bulletin, purporting to show how the benefits of
modern genetic techniques can be applied to the Dexter breed. There was one
useful bit of information in the article, the reference to "Managing Breeds for a
Secure Future", a book written by DP Sponenberg and DE Bixby, published in
2007. Professor Sponenberg was hitherto unknown to me, but I learned that
he is now a member of the DCS team of Genetic Advisors, is a highly qualified
and respected authority in the USA, and I would commend his book to
everyone. Being interested in exactly what he says about "the standard three
test of Phenotype, history and genetic analysis" as quoted by Andrew Sheppy,
I purchased a copy of the book and have read it from cover to cover. It is
highly readable, requiring little specialist knowledge to understand, and is, in
short, a wonderful exposition of exactly what a breed is and what is needed to
keep it genetically healthy. I have begun, but not completed, an attempt to
purchase a number of copies for distribution in UK, and the first recipients
should be without a doubt, all our DCS council members.
An understanding of the dynamics of the genetic makeup of a breed lets us
understand the slow loss of genetic variability within a closed breed over a
period of time, and as an antidote to that the value of occasional added
genetic material. This added material may be in the form of "grading up" as an
official breed society policy, or it may happen by accident through mistaken
registration of outcrosses as purebred animals. In fact it matters little in the
longer term which happens, as long as the resulting offspring from any such
"impure" individuals are selected according to breed standards. Seven
generations down the line we have less than 1 of the genetic input of the
introduced genetics. Of course most of the 1 consists of genes common to
all cattle. The advantage to the breed is the replacement of some of the
genetic material lost in the course of closed breeding, which happens unseen
and unrecorded. It is interesting to note that one of the findings of the Cardiff
20
project was that the Dexter breed, though showing evidence of being very
much a distinct and identifiable breed, possessed a great degree of genetic
variability, the sign of a healthy breed.
In Andrew Sheppy's article on "Introgression in Historic Dexter Bulls" we find
him applying the three standard tests as suggested by Prof Sponenberg. But
let us look at the reliability of Andrew's evidence placed in each of the three
parts of the test. As far as the first "History" is concerned, in the first two
cases, we find Mr Sheppy relying on hearsay evidence, from family members
of deceased breeders. In the case of Charley Pudding he says "it was
admitted" and we have to ask, by whom, and would they have been in a
position to give such a statement. In the case of Shadwell Robert, the historic
evidence comes from alleged statements from a niece of the breeder. It is well
recognised by those with long experience of the breed, that the two sisters of
the family concerned had a very poor relationship and thus family
disagreements enter the arena and cloud the evidence. That accounts for the
historic evidence in the case of the first two bulls in the paper. For the third bull
in the paper, Grinstead Plover, the historic evidence is so flimsy that it enters
the realms of the fantasy world of the emperor's new clothes. We are expected
to believe that Lady Loder, one of the foremost and most respected breeders·
of her time, was either so deceitful, or so stupid, that she either ignored, or did
not notice, that a bull reared in her herd from a calf, was polled, at a time when
the whole herd was horned, no calves being dehorned. Worse still, Lady Loder
then sold the bull, and Beryl Rutherford, one of the most observant people I
have ever encountered, did not notice that a bull with no horns was being sold
from a horned herd, and that 50 of his calves were polled. The assumptions
made by Andrew Sheppy are a dreadful slur on the reputation of some of our
most significant and most respected influences on the breed. He also expects
us to believe that the dun colour, having entered the Red Poll breed when the
Suffolk Dun merged with the Norfolk Red, emerged in Grinstead Plover. What
Andrew does not tell us, is that the Suffolk Dun and the Norfolk Red merged in
the 1840's. How many generations do we go down from 1846 to 19667 With
the Red Poll breed selecting so strongly for both red and polled, it seems to
me that Mr Sheppy's version has little credibility. Moreover, there are recorded
dun Dexters on both sides of the Atlantic which are not descended from
Grinstead Plover.
For the future, given the biases and questionable conclusions of Mr Sheppy, I
would urge DCS Council to disregard him as a "genetic advisor", to
concentrate on advice from properly qualified geneticists, such as Professor
Sponenberg, and Prof. John Woolliams of the Roslin Insitute. Now that I think
on it, Dr John Woolliams was listed by our DCS council Chairman when I
pushed her to name the genetic advisors, though he does not appear on our
website as such. Please, DCS Council, consign the advice based on hearsay
and bias to the bin, concentrate on the advice of properly qualified
professionals, and, most importantly, READ PROFESSOR SPONENBERG
AND BIXBY'S BOOK. Council owe it to the Society they run to be better
informed.
Duncan Macintyre BVMS MRCVS
My response to 'Introgression in Historic Dexter Bulls'
I read with interest and not a little concern, Andrew Sheppy's article
"Introgression in Historic Dexter Bulls", which appeared in the last Bulletin.
Whilst I am the first person to support the preservation of as many separate
bloodlines within the breed as possible, particularly the old long standing lines
such as Ypsitty and Woodmagic, and worked on various projects to achieve
this when I was on Council, I do not think that it is in the interests of the
Dexter Breed to continue to delve back into the past, producing theories (not
facts) about the pedigrees of various animals, and in the course of doing so
discredit the breeding of some of the most significant herds of the last century.
Mr Sheppy's "History Facts" are based on hearsay. I was a great admirer of
Valerie Roberts and indeed awarded her the President's Trophy, but she was
very much of the old school who believed that a Dexter wasn't a Dexter
unless it produced a bulldog calf. Shadwell Robert was one of the few bulls
bred in the 1960's, (apart from Woodmagic bulls), who was a non-carrier, so I
can well imagine that Valerie may have thought there was something "fishy"
about him, as she once said to me. She also made it very clear that there was
absolutely no love lost between herself and her aunt who owned the Strebor
herd, in fact she had very little to do with her, so basing any conclusions about
the breeding of Shadwell Robert on anything that Valerie may have said is
very unsound.
Beryl Rutherford, was at the other end of the spectrum from Valerie, although
they both lived for their Dexters. She was extremely knowledgeable about
genetics, and one of the most honest people I have ever known. She was
passionate about her herd and about preserving the purity of the Dexter
breed, and I am quite sure she would not have based her herd on the
breeding of an animal if she had any suspicion at all that it was not a pure
Dexter. If Grinstead Plover was by a Red Poll bull, he would more than likely
have been polled himself. Beryl told me that from a welfare point of view, she
would love to find a Dexter bull which she considered to be pure and polled.
Surely if Grinstead Plover carried a polled gene and Beryl had believed him to
be a pure Dexter, she would have selected polled offspring, but her herd was
horned, as was the Bryn-y-Pin herd, based predominantly on Wood magic
breeding. The Woodmagic Herd and the Ypsitty Herd were both identified by
the Cardiff project as being genetically distinct from most of the other animals
profiled, but as these were closed herds (the Woodmagic herd for a much
longer period), genetic drift away from the main population is to be expected.
As far as the genetic analysis is concerned, I would like to know exactly how
many DNA profiles the bulls mentioned have been compared with. The article
states that "a comparison with all the purebred Dexter samples from the UK
and a selection from the USA". The database of profiles given to the Society
as a result of the Cardiff Project, contains 140 animals including the few
deemed to be pure, by Mr Sheppy. At the time, I thought the total number of
18
animals ana lysed for this project to be disappointingly few in comparison with
the numbers of animals in the current population and tried to persuade Cardiff
to sample a wider selection, including another closed herd, or at least to use
some of the profiles we now have recorded in the Society office. The Society
samples only use 16 markers, rather than the 23 Cardiff were using, but 15
out of 16 were the same, and Professor Bruford, who was supervising the
project was quite taken aback, when I pointed this out to him, as he had not
been made aware that the Society DNA profiles existed and acknowledged
that they could have been useful if he had known about them sooner.
Unfortunately, by the time the DCS Council received any details about the
research, despite several requests for updates, the project was well into its
second year and time was limited. Several breeders, including myself
supplied hair samples which were not used - again disappointing as my
opinion has always been that the Society could have gained much more than
it did for the cost of this project.
The main very positive conclusion of the Cardiff thesis was that the Dexter is
a distinct breed, with no significant evidence of introgression from other
breeds, but with a healthy amount of genetic variation within the breed, which
rather begs the question of why Mr Sheppy is continuing to try and prove
otherwise. If Mr Sheppy's work has used animals other than those profiled for
the Cardiff thesis, I am curious to know how many and who has funded this,
as DNA profiling is not cheap, even if only 16 markers are used, as anyone
who has registered a bull will know and although as Mr Sheppy states,
modern genetic techniques are available, I was told in a discussion with
Professor Liz Glass from Roslyn at the Scottish Group AGM, that a full DNA
profile to enable detailed study of an animal's genome still costs in the region
of £250!
As we cannot parent verify any of the animals concerned, the data recorded
in the old Society Herd Books should be accepted as correct. We now have
the tools to check on suspect animals and amend any mistakes as they arise,
and this has been done several times, to my certain knowledge over the last
25 years.
We need to move on and consider how best to improve and promote our
breed today, rather than dwelling on what mayor may not have happened 50
or 60 years ago.
Veronica Schofield
I read with interest and not a little concern, Andrew Sheppy's article
"Introgression in Historic Dexter Bulls", which appeared in the last Bulletin.
Whilst I am the first person to support the preservation of as many separate
bloodlines within the breed as possible, particularly the old long standing lines
such as Ypsitty and Woodmagic, and worked on various projects to achieve
this when I was on Council, I do not think that it is in the interests of the
Dexter Breed to continue to delve back into the past, producing theories (not
facts) about the pedigrees of various animals, and in the course of doing so
discredit the breeding of some of the most significant herds of the last century.
Mr Sheppy's "History Facts" are based on hearsay. I was a great admirer of
Valerie Roberts and indeed awarded her the President's Trophy, but she was
very much of the old school who believed that a Dexter wasn't a Dexter
unless it produced a bulldog calf. Shadwell Robert was one of the few bulls
bred in the 1960's, (apart from Woodmagic bulls), who was a non-carrier, so I
can well imagine that Valerie may have thought there was something "fishy"
about him, as she once said to me. She also made it very clear that there was
absolutely no love lost between herself and her aunt who owned the Strebor
herd, in fact she had very little to do with her, so basing any conclusions about
the breeding of Shadwell Robert on anything that Valerie may have said is
very unsound.
Beryl Rutherford, was at the other end of the spectrum from Valerie, although
they both lived for their Dexters. She was extremely knowledgeable about
genetics, and one of the most honest people I have ever known. She was
passionate about her herd and about preserving the purity of the Dexter
breed, and I am quite sure she would not have based her herd on the
breeding of an animal if she had any suspicion at all that it was not a pure
Dexter. If Grinstead Plover was by a Red Poll bull, he would more than likely
have been polled himself. Beryl told me that from a welfare point of view, she
would love to find a Dexter bull which she considered to be pure and polled.
Surely if Grinstead Plover carried a polled gene and Beryl had believed him to
be a pure Dexter, she would have selected polled offspring, but her herd was
horned, as was the Bryn-y-Pin herd, based predominantly on Wood magic
breeding. The Woodmagic Herd and the Ypsitty Herd were both identified by
the Cardiff project as being genetically distinct from most of the other animals
profiled, but as these were closed herds (the Woodmagic herd for a much
longer period), genetic drift away from the main population is to be expected.
As far as the genetic analysis is concerned, I would like to know exactly how
many DNA profiles the bulls mentioned have been compared with. The article
states that "a comparison with all the purebred Dexter samples from the UK
and a selection from the USA". The database of profiles given to the Society
as a result of the Cardiff Project, contains 140 animals including the few
deemed to be pure, by Mr Sheppy. At the time, I thought the total number of
18
animals ana lysed for this project to be disappointingly few in comparison with
the numbers of animals in the current population and tried to persuade Cardiff
to sample a wider selection, including another closed herd, or at least to use
some of the profiles we now have recorded in the Society office. The Society
samples only use 16 markers, rather than the 23 Cardiff were using, but 15
out of 16 were the same, and Professor Bruford, who was supervising the
project was quite taken aback, when I pointed this out to him, as he had not
been made aware that the Society DNA profiles existed and acknowledged
that they could have been useful if he had known about them sooner.
Unfortunately, by the time the DCS Council received any details about the
research, despite several requests for updates, the project was well into its
second year and time was limited. Several breeders, including myself
supplied hair samples which were not used - again disappointing as my
opinion has always been that the Society could have gained much more than
it did for the cost of this project.
The main very positive conclusion of the Cardiff thesis was that the Dexter is
a distinct breed, with no significant evidence of introgression from other
breeds, but with a healthy amount of genetic variation within the breed, which
rather begs the question of why Mr Sheppy is continuing to try and prove
otherwise. If Mr Sheppy's work has used animals other than those profiled for
the Cardiff thesis, I am curious to know how many and who has funded this,
as DNA profiling is not cheap, even if only 16 markers are used, as anyone
who has registered a bull will know and although as Mr Sheppy states,
modern genetic techniques are available, I was told in a discussion with
Professor Liz Glass from Roslyn at the Scottish Group AGM, that a full DNA
profile to enable detailed study of an animal's genome still costs in the region
of £250!
As we cannot parent verify any of the animals concerned, the data recorded
in the old Society Herd Books should be accepted as correct. We now have
the tools to check on suspect animals and amend any mistakes as they arise,
and this has been done several times, to my certain knowledge over the last
25 years.
We need to move on and consider how best to improve and promote our
breed today, rather than dwelling on what mayor may not have happened 50
or 60 years ago.
Veronica Schofield
