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Home , Cleveland Bay, Thoroughbred

ANNEX G Related Background Reading

“Waiting on Providence " never did nor ever will be attended with satisfactory results – Scarth Dixon

The sentiment in the statement above made by a man who is revered in the history of the Cleveland Horse Society, William Scarth Dixon. He was a founder member of the Horse Society in 1884 being its first secretary and what he said was perhaps prophetic for the present times. Not waiting on providence is at the core of the Grading Register proposal.

Contents

1. Dr Phillip Sponenberg DVM, Ph.D. - The CBHS has been asked not to publish this article in a PDF document format. It may be seen on the RBST website via the following link: http://www.rbst.org.uk/files/Graspingthe%20Nettle%20- %20Should%20we%20or%20Shouldn't%20we%20Part%201.pdf 2. Dr Ian Gill - The CBHS has been asked not to publish this via a PDF document format. It may be seen on the RBST website via the following link: http://www.rbst.org.uk/files/Grasping%20the%20Nettle%20- %20Should%20we%20or%20Shouldn't%20we%20Part2.pdf 3. Akhal-teke 4. Friesian horses 5. CBHS Book selections

SELECTED PAGES FROM THE WEBSITE OF THE Akhal-teke http://www.akhalteke.info/inbreeding-depression-1-51-en.html

InbreedingDepression depression is reduced fitness in a given population as a result of the breeding of related individuals. Breeding between closely related individuals, called inbreeding, results in more recessive deleterious traits manifesting themselves The more closely related the breeding pair is, the more homozygous deleterious genes the offspring may have, resulting in very unfit individuals. Another mechanism responsible is over dominance of heterozygous alleles leading to a reduction in the fitness of a population with many homozygous genotypes, even if they are not deleterious. Currently it is not known which of the two mechanisms is more important. In general, populations with more genetic do not suffer from inbreeding depression. Inbreeding depression is often the result of a population bottleneck

Natural selection cannot effectively remove all deleterious recessive genes from a population for several reasons first, deleterious genes arise constantly through mutation within a population second, in a population where inbreeding occurs frequently, most offspring will have some deleterious traits, so few will be more fit for survival than the others. It should be noted, though, that different deleterious traits are extremely unlikely to equally affect reproduction. An especially disadvantageous recessive trait expressed in a homozygous recessive individual is likely to eliminate itself, naturally limiting the expression of its phenotype.third, recessive deleterious alleles will be "masked" by heterozygosity, and so heterozygotes will not be selected against.Introducing new genes from a different population can reverse inbreeding depression. Different populations have different deleterious traits, and therefore will not result in homozygosity in most loci in the offspring. This is known as outbreeding enhancement, practiced by conservation managers and zoo captive breeders to prevent homozygosity. However, intermixing two different populations may give rise to unfit polygenic traits in outbreeding depression.Inbreeding depression is expressed in a variety of results, some of them are:significant reduction of lifespansdecreased fertility and fecundityfluctuating asymmetries and morphological variation disease susceptibility decrease in size

At least one population of horses bred with a closed studbook is known, which has been and still is going through a severe inbreeding depression, including several lethal and semi-lethal recessives having surfaced, as well as grave problems to general health and fertility. In fact, all of the above mentioned results are being experienced by this . This is the Friesian horse, with a current breeding population of some 8,000 to 10,000 individuals, a general COI of 17%, one major bottleneck around 1900 (3 registered sires left) and breeding practice which includes color-breeding, show breeding, popular sires and severe culling towards visual and performance traits. These days there are roughly 100 per year suffering from dwarfism and from hydrocephalus (often enough killing the birthing as well) in the Netherlands alone, with a significant higher amount of mares suffering from a variety of fertility- related issues, such as e.g. retention of the placenta, low rates of mares taking or lower semen quality. Additionally the breed is susceptible to a higher and severer incidence of colics and quite some skin and allergy-related issues.The Friesian breed management is at long last reacting to these problems, though the measures have been out to be not efficient enough. Inbreeding is discouraged, with COI data being rendered to the breeders upon registration of the foals, a moderate opening of the studbook towards horses formerly rejected as breeding animals has taken place with Appendix sections I and II and data about horses spreading dwarfism is given to the breeders. It is noteworthy that inspite of the lethality of several of these defects and inspite of the quite severe culling in evidence among this breed (far surpassing that of e.g. the Akhal Teke), there is no noteworthy amount of purging evident. Another population with closely maintained statistical records, the English , has also been found to be adversely influenced by COI exceeding 10%.

Recent research has found that different species and different within one species do not react in the same manner to inbreeding. Factors in this regard are the genetic health status of the breed founders, the amount of diversity being cut off within a set time, abrupt changes in selection and culling methods, change of breeding criteria or likelihood to evolve mutations. A further factor is how steadily and how fast inbreeding coefficients are rising within a breed. If the genetic load encompasses more medium-import deleterious recessives instead of lethal ones, then there is no or only a very low purging effect to be found, a lack which also furthers inbreeding depression.

As to the Akhal Teke, the close observer already is able to discern the telltale signs, such as a continueing reduction of lifespans, an ever rising amount of barren mares, aborted, deadborn or weakborn foals, poor semen quality in older sires, lately also in younger studs, as well as of course the rising amount of lethal recessives cropping up among the breed. Due to the habit of mostly linebreeding, instead of close inbreeding, the general COI of the breed is better than that of e.g. the Friesian. However, the AVK is much worse and lessening each generation by several points. There are currently no horses with an AVK above 55% and a growing fastly amount of horses with one under 35%, this after barely 10 to 12 registered generations! This constitutes a loss of diversity not expressed by simple COI data, but one which nevertheless has the same effects and it is a quite enormous loss.

The horses were breeds of enormous diversity, having existed up to the 1900 bottleneck in huge numbers (herds of 100,000 horses among one tribe only were not unheard of), a huge amount of landrace strains and free interbreeding within these breeds and strains. Whole chunks of this vast genepool were destroyed at the same time, even the surviving 650-700 horses which entered the first studbook were not used completely, large portions of that small group did not make it into the modern genepool at all. It needs to be remembered that during this crucial survival phase the breed was culled on size and on race results, even though there should have been no culling at all. The overall COI is rising currently in a curve rather than in a linear manner, aided by the opinion of many breeders, that linebreeding is no inbreeding, and little to no awareness of these problems among western breeders. Already there are quite a few horses having COIs of 10+%.

Omertà - or the Conspiracy of Silence. The expression "conspiracy of silence" relates to a condition or matter which is known to exist, but by tacit communal unspoken consensus is not talked about or acknowledged. Conditions considered shameful or disadvantageous by society or a certain group of people result in avoidance of recognition of some in order to officially bury or hide it and thus prevent accusations, investigations or liability. A conspiracy of silence in some field has effects at many levels: those who are directly suffering, or causing others to suffer, perpetuate their cycle of harm and suffering, those who have suffered have their suffering extended by being having their condition ignored or minimized, and are not considered seriously or redressed appropriately, lessons that might be learned for the future are not learned, conditions are exacerbated or even this way allowed to become entrenched in the first place.

Conspiracy of silence is a well-known and much executed behaviour among many if not most modern breeders. Unlike breeders of former times, who had to present animals well able to perform and had no problem with destroying those individuals which were showing faults or defects, especially as their livelihood usually depended on their good name in this respect, many if not most modern breeders are more or less hobbyists or - if themselves professionals - selling mainly to hobbyists. Unless they are selling directly to the meat market that is. These hobby breeders usually feel that the name of their breeding is riding on the health state of their animals, or indeed often considerable amounts of money invested are riding on the trust customers and fellow breeders place in them or they do not wish to start over rsp. are unable to buy new breeding stock.

In view of the fact that since roughly 100 to 150 years ago studbooks of most pet breeds are closed as a rule and in view of the advent of pure showbreeding also among many if not most pet animal species, decisive and relentless culling has become more necessary than ever. As can be seen in nearly every pet breed which deviated from breeding for practical work, the (on genetic and general health) of inbreeding, genetic load, popular sire syndrome and omertà has led to genetic diseases cropping up and spreading through the genepools, as well as a general loss of health values. While horse breeds are not affected as fastly as small pet breeds due their larger generation span, they most certainly are not immune to this mechanism. Quarterhorses with HYPP, HERDA or EPSM, Arabians with LFS, SCID or CA, or Friesians with hydrocephalus or dwarfism, these are just a few examples for genetic diseases spreading like wildfire through either closed genepools or genepools bred heavily for show and perusing largely popular sires to do that.

In all of these cases, in every one of them, the conspiracy of silence has seen to it, that the silence of breeders and owners alike allowed the initially but few cases of grave genetical diseases to spread throughout the whole breed, in some cases to the extent that so many individuals are carriers that culling becomes impossible. Only when so many animals are touched by the relevant problem, that at one or other point affected horses get sold to people unwilling to keep silent about it, a grudging acceptance takes place. Rescue measures at that stage then come much too late and the usual testing frenzy is more often than not just window dressing.

An additional problem is that in small, closed genepools even with testing there soon comes a point when the genepool consists of so many carriers that finding good, fitting breeding pairs is a major difficulty. The longer a disease is not talked about and not taken into calculation, the sooner that state will be . E.g. among Friesians this already has resulted in semi-opening of the before firmly closed studbook and strict rules as to lower inbreeding coefficients. This, one needs to say it clearly, is a breed with way more than 10,000 breeding individuals worldwide and still it was discovered to not be sufficient to cull within the closed genepool only.

The situation for the Akhal Teke with its much, much lower amount of breeding animals, may quickly become much more serious. Already today the genetic diversity of the breed is insanely low, an AVK of 30-50% (instead of at least 85%) in modern horses should ring any breeder's alarm bells long and hard. Next comes the fact that we already know that several of the extremely popular sires were or must have been carriers of the lethal recessive "Hairless Syndrome". Such horses as 943 Arslan, 736 Keymir or 1054 Gilkuyruk, cases leading back to the immensely influental 448 Kir Sakar, 44 Bek Nasar Dor or 244 Toporbay, can be found by now in every single horse pedigree. That general genetic load and inbreeding depression also is by now taking its toll, should not be negated either, with a major lowering of the average life expectancy of the more recently born horses and the cropping up of such potentially polygenetic diseases as Wobbler Syndrome, Kissing Spine, ringbone, allergies, DLSD or OCD.

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Effect of inbreeding on the incidence of retained placenta in Friesian horses (Whole article recommended further reading – seach for above title)

...... In conclusion, the findings of the present study show a strong inbreeding rate in the total Friesian horse population over the last decades. The present findings indicate that the high incidence of RP in Friesian horses is, at least partly, a result of inbreeding. Reduction of the inbreeding rate by increasing the effective breeding population is required in order to avoid a further increase in the incidence of RP in Friesian mares. The findings of our study support our hypothesis that the incidence of retained placenta in Friesian horses is associated with inbreeding. Due to this association, combined with the determined strong inbreeding trend over the last decades, a further increase of the high incidence of retained placenta is to be expected, unless appropriate measures are taken. Reduction of the inbreeding trend is required, which can be achieved by increasing the effective breeding population. A substantial increase of the number of sires used would be the most effective measure. Emphasizing the usefulness of sire/dam combinations that produce offspring with relatively low inbreeding coefficients should be part of the breeding policy. Because the estimated heritability is low, selection against retained placenta would likely result in slow progress.

SELECTION OF EXTRACTS FROM CBHS STUD BOOKS ON THE EVOLUTION OF THE CB BREED VOLUME 15 - SIR ALFRED PEASE

Great progress has been made, since the First Volume of this Stud Book was compiled, in tracing the descent and evolution of the different races and breeds of horses as we know them today. It is clear that, technically speaking, there is no such thing as a ‘pure breed’ of horses in these islands. One thing is certain, that whilst we were correct forty years ago in claiming that the Cleveland Bay breed was ‘clear of’ what we now call carting blood (i.e., the hairy-legged type, such as Clydesdale, Shire, Old Black and their forbears; types which never existed at all in these parts during the evolution of the Cleveland Bay). We were wrong in supporting the claim that the breed was also ‘clear of Blood’. What is true is this: whereas Racing Blood did contribute to the evolution of the Cleveland Bay in the 18th Century (and the Oriental contribution to his form and character was then ‘set’ and continues clearly marked to-day), the type then ‘fixed’ has remained true and has practically been kept clear of admixture since.

In every Cleveland Bay and in most Coach Horse pedigrees, which can be extended into the 18th Century, you find these breeds ultimately resolve themselves into unknown ‘Cleveland’ or ‘Chapman’ blood in the female line, and into ‘Blood’ in the male line. All that can be truthfully asserted is that the ‘Cleveland Bay’ type was evolved from a small admixture of the best Racing Blood generations ago, when the qualities of courage and endurance were put to the highest tests on the Turf, and that the modern Thoroughbred contributed nothing to the breed.

The case with the is entirely different; the Thoroughbred has been largely and continuously used down to the present time. Of the Blood sires which contributed to the evolution of the Cleveland Bay, I consider Manica (by the ) and Jalap (by Regulus, by The , which was a Barb) to be the chief contributors. Manica appears far more frequently than any other Thoroughbred sire. Whenever you have Dart 83* and "Ellerby's Horse" you get Manica. These are found at the root of every pedigree of existing Cleveland’s. There are at least 46 crosses of Manica in Hindson's Sportsman 299 (a typical Cleveland of 1876), and the record of his pedigree is a very short one, the breeding of his great-grandam being unknown.

INTRODUCTION TO VOLUME 22 – 1966 The first aim of any Breed Society must be the preservation of the inherited virtues of that breed. It was for this purpose that the Stud Book was started in 1884, and has been maintained ever since. This Stud Book is not, however, ‘closed’, as it is in the case of the Thoroughbred. Cleveland Bay breeders have always claimed that Cleveland blood is so dominant that four or five top crosses of it (resulting in an animal of 15/16ths or 31/32nds pure blood) produce something indistinguishable from a 100% Cleveland. Consequently, in addition to the Stud Book, a Register (for female stock only) is maintained and mares entered in it are treated in exactly the same way as those entered in the Stud Book proper, save that their foals are not recognised—they are not eligible for entry in either the Stud Book or the Register. They may also not be shown (after they are weaned) in classes for pure-bred animals, and they receive no grants of any from the Society. They are, in fact, treated as if they were cross-bred. foals by a pure Cleveland Bay horse from a registered can also only be entered in the Register (save as mentioned later).

To for the Register, a mare must first be approved by the Editing Committee of the Cleveland Bay Horse Society, as fulfilling conditions set out at length in Vol. 18 of the Stud Book. To summarise these; they require one parent entered in the Stud Book and the other having a fair proportion (usually taken as 50%) of pure Cleveland blood. After being passed 'by the Editing Committee as suitably bred, the mare has to be approved by the Society's Inspectors as being of true Cleveland Bay type and colour (Bay with black points; no white hairs save for a small white star or a few white hairs in the heel). If she gets over this hurdle she is entered in the Register.

Mares with three crosses of pure Cleveland blood from a Registered mare (i.e., the great-granddaughter of the mare originally registered, whose sire, grandsires and great-grandsires are all horses entered with a name and number in the Stud Book of the Cleveland Bay Horse Society) can, by a resolution passed at the Annual General Meeting of the Society in October, 1961, be admitted to full entry in the Stud Book. Their breeding must satisfy the Editing Committee, and they must pass an inspection by the Society's Inspectors at three years old or over. This inspection is naturally even more rigid than that given to mares which only seek admission to the Register, but it is gratifying to record that the first mare to gain full admission to the Stud Book under the 1961 resolution was Mr. J. S. Sunley's " Princess Emeralda," who was breed at the Great Yorkshire Show in 1962. The Society, then, is carefully guarding the type and purity of the breed, and many people may wonder why. They point out that the agricultural horse's day is past, that is only a hobby, that the demand for coach horses is too small to warrant the preservation of a breed especially to supply it, that the Cleveland is too heavy ever to be universally popular as a horse. They say, quite rightly, that the Cleveland/Thoroughbred cross has for years been much more in demand than the pure Cleveland. All this is perfectly true, and breeders must face the fact that both now and in the future the Cleveland Bay is wanted not for itself but for what can be bred from it. But this unpalatable fact has been faced with equanimity by other Breed Societies before now.

CBHS STUD BOOK VOLUME 15 Review of 1920 Major Fair-Blakeborough, Secretary to the CBHS: ‘We live in an isolated part of the world, yet not more isolated or less famous than was Arabia in 1783, in which year Mr. sent from Aleppo, to his brother in Yorkshire, the famous Darley Arabian, whose blood plays such an important part in the pedigrees of many of to-day, and is found far back in the pedigrees of some Cleveland Bays, the Royal winner H.M. the King's Beadlam Briscoe for instance’.

THE CLEVELAND BAY, PAST, PRESENT AND FUTURE By SIR A. E. PEASE, BART (President of the Cleveland Bay Horse Society).

………….but with the present Instructions to Judges, 1920, which are as follows: The Cleveland Bay should exhibit the best combination of strength with activity, i.e., muscular draught and weight, combined with quality, courage and stamina. The Cleveland should be capable of doing every kind of draught. Height: Standard height is 15.3 to 16.o hh, but height should not disqualify a good sort on short legs. Colour: The Cleveland should be a Bay: that is to say, in order of preference ‘Bright’ or ‘Clear’ Bay. Dark Bay has been liberally interpreted to include a colour approaching Brown. This is an admissible but not a correct colour; or Light Bay, with Black Points, i.e., Black legs, Black and Black tail. Note: Grey hairs in mane and tail do not disqualify: these have been long recognised as a feature in certain strains of pure Cleveland blood. WHITE is not admissible beyond a very small star and a few grey hairs in heel or coronets. Legs: Which are bay or red below the knees, and hocks, do not disqualify, but are faulty as to colour. The legs should be clear of superfluous hair, and as clean and hard as possible. Body: The body should be wide and deep. The back should not be too long, and should be strong, with muscular loins. The shoulders should be sloping, deep and muscular. The quarters should be level, powerful, long and oval, the tail springing well from the quarters. The head is characteristic of the breed and is often rather large, but should be well carried on a rather, long lean neck (like a rag on a stick.) The Limbs: The arms and thighs and second thighs should be muscular. The knees and hocks large and well closed. There should be 9 inches upwards of bone below the knee. The ankles should be neat, clean and not too big with the pasterns sloping. The Feet: The feet must be of the best. The Action: Must be true, good and free. High Action is not characteristic of the breed. The Cleveland which moves well is full of courage and will flex his knees and hocks sufficiently. The action required is free all round, gets over the ground, and fits the wear-and-tear qualities of the breed.

SUMMARY - SIR ALFRED PEASE

All that can be truthfully asserted is that the Cleveland Bay type was evolved from a small admixture of the best Racing Blood generations ago, when the qualities of courage and endurance were put to the highest tests on the Turf. Of the Blood sires which contributed to the evolution of the Cleveland Bay, I consider Manica (by the Darley Arabian) and Jalap (by Regulus, by The Godolphin Arabian, which was a Barb) to be the chief contributors. Manica appears far more frequently than any other Thoroughbred sire. Whenever you have Dart S3* and "Ellerby's Horse" you get Manica. These are found at the root of every pedigree of existing Clevelands.

There are at least 46 crosses of Manica in Hindson's Sportsman 299 (a typical Cleveland of 1876), and the record of his pedigree is a very short one, the breeding of his great-grandam being unknown. The purely oriental character of the Cleveland Bay quarter and set of the tail has often struck me. I have little doubt this comes chiefly through Manica. The Thoroughbred has comparatively little Arabian blood in his veins, and a great deal of Barb blood, and owes much to the latter. The Cleveland Bay quarter and spring of the tail is nearer the Arabian than the Barb.