| © Chris Milvain 2006 |
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WELSH PONIES AND COBS come in a wide variety of colours - the description in the Standard of Excellence says ‘Any colour except skewbald or piebald’. This terminology, inherited from the parent body, The Welsh Pony & Cob Society (UK), is rather outdated but in this instance describes horses produced by the tobiano and/or overo genes, either separately or combined, neither of which are known to be present in Welsh Ponies and Cobs. The genetics behind coat colour in horses and ponies is well understood by geneticists and new research continues to increase the knowledge base. Lay people often find it a very confusing subject and it is indeed complex; no colour is produced by a single pair of genes and each colour is the result of complex interrelationship. To add to the confusion, colour identification is often difficult because shades within each colour can vary due to the presence and influence of various modifying genes.
THE BASIC COLOURS There are four base colours of horses, these being chestnut, black, bay and brown. Bay and brown are sometimes considered separately, but for the purposes of this breeding chart they are grouped together as the possible colour results quoted here would be the same whether the animals are brown or bay. While the matings described here can be expected to produce the nominated colours, unexpected colours can still occur from time to time - these will most often be due to misidentification of the colour of the parents, but there are some possible effects not listed here, as well as the unlikely possibility of genetic mutation. Apparent anomalies can be resolved by DNA typing of both parents and the offspring. Also, it is now possible to test horses for the presence of some colour genes using DNA testing. In all cases, the likelihood of a particular colour being produced is dependent not only on the appearance of the parents (the phenotype), but on their genetic makeup (the genotype) which they have inherited from their parents. CHESTNUT ‘Chestnut’ describes the colour of a pony whose coat is red. There are many shades of chestnut, from a light orangey colour through to very dark or liver chestnut. White markings can occur on the face and legs. The coat colour of chestnut ponies is modified by the presence or absence of many genes including those which produce sootiness, and the genes which modify the lower leg colour, which include ‘ivory’, which produces lighter colour on the lower limbs, and ‘tostado’ which produces a darkening of the lower limbs. Any shade of chestnut can have a flaxen mane and tail. Chestnut is the most recessive colour; non-chestnut parents can produce chestnut offspring. Chestnut mated to chestnut will always produce chestnut - but some chestnuts may be misidentified, ie, be registered as palomino or bay. CHESTNUT x CHESTNUT Chestnut CHESTNUT x BLACK Chestnut, black, bay, brown CHESTNUT x BAY or BROWN Chestnut, bay, brown, black CHESTNUT x PALOMINO Chestnut, palomino CHESTNUT x BUCKSKIN Chestnut, palomino, black, dilute black, bay, brown, buckskin CHESTNUT x CREMELLO Palomino CHESTNUT x PERLINO Palomino, buckskin, dilute black. CHESTNUT x ROAN 50% of offspring will be roan, with the base colour determined as above, depending on the base colour of the roan parent. CHESTNUT x DUN 50% of offspring will be dun unless the dun parent is homozygous for dun in which case all progeny will be dun, with the base colour determined as above, depending on the base colour of the dun parent. CHESTNUT x GREY 50% of offspring will go grey unless the grey parent is homozygous for grey in which case all progeny will go grey, with the base colour determined as above, depending on the base colour of the grey parent. BLACK ‘Black’ describes a pony whose hair is uniformly black, except for white markings on the face and legs. Two types of black coat exist - fading and non-fading (jet black). Jet black ponies are born a charcoal or bluish black and in their mature coat exhibit a metallic sheen, iridescent or bluish in colour. Fading black ponies may be born a smoky or ash colour or brownish/bay shade but develop their black colour on the first change of coat; the mature coat only rarely has a metallic sheen. BLACK x BLACK Black, chestnut, brown, bay BLACK x CHESTNUT Black, chestnut,bay, brown BLACK x BAY or BROWN Black, bay, brown, chestnut BLACK x PALOMINO Black, dilute black, chestnut, palomino, bay, brown, buckskin BLACK x BUCKSKIN Black, dilute black, chestnut, palomino, bay, brown, buckskin BLACK x CREMELLO Dilute black, palomino, buckskin BLACK x PERLINO Dilute black, palomino, buckskin BLACK x ROAN 50% of offspring will be roan, with the base colour determined as above, depending on the base colour of the roan parent. BLACK x DUN 50% of offspring will be dun unless the dun is homozygous for dun in which case all progeny will be dun, with the base colour determined as above, depending on the base colour of the dun parent. BLACK x GREY 50% of offspring will go grey unless the grey parent is homozygous in which case all progeny will go grey, with the base colour determined as above, depending on the base colour of the grey parent. BAY & BROWN BAY ponies have a reddish body coat colour with black on the lower limbs and a black mane and tail. The ears usually have a black line around them. White markings can occur on the face and legs. The body coat colour varies and these colours are often described as blood bay, mahogany bay, golden bay, light bay etc. The lighter shades can sometimes be misidentified as ‘buckskin’, or ‘dun’. Unless the pony has a dilute parent, whether the dilution is caused by the ‘cream’ dilution, the ‘dun’ dilution or the ‘taffy’ dilution, it cannot be a buckskin, dun or taffy. BROWN ponies have a mixture of brown and black hairs spread over the body except in the soft parts, ie, around the muzzle and eyes, behind the elbows, in the flank, and sometimes between the hind legs, where the hair is of a lighter colour, sometimes described as ‘mealy’ but may be tan or yellowish. While the sequence of genes which produce bay or brown is slightly different, the inheritance is similar so that the following colour matings can be expected to produce the same range of possible colours. BAY or BROWN x BAY or BROWN Bay, chestnut, black, brown BAY or BROWN x BLACK Black, brown, bay, chestnut BAY or BROWN x CHESTNUT Black, brown, bay, chestnut BAY or BROWN x PALOMINO Black, dilute black, chestnut, palomino, bay, brown, buckskin BAY or BROWN x BUCKSKIN Bay, brown, buckskin, black, dilute black, chestnut, palomino, BAY or BROWN x CREMELLO Dilute black, palomino, buckskin BAY or BROWN x PERLINO Dilute black, palomino, buckskin BAY or BROWN x ROAN 50% of offspring will be roan, with the base colour determined as above, depending on the base colour of the roan parent. BAY or BROWN x DUN 50% of offspring will be dun unless the dun is homozygous for dun in which case all progeny will be dun, with the base colour determined as above, depending on the base colour of the dun parent. BAY or BROWN x GREY 50% of offspring will go grey unless the grey parent is homozygous for grey in which case all progeny will go grey, with the base colour determined as above, depending on the base colour of the grey parent. THE DILUTE COLOURS There are three main types of dilution which lighten the basic colour. These are the cream dilution, dun and taffy. In some ponies more than one dilution factor may be present. The cream dilution is the one which is most commonly seen in Welsh Ponies and Cobs. CREAM dilution is produced by a gene with incomplete dominance. When present once, (ie the animal is heterozygous for the cream), the dilution acts on chestnut coat colour to produce palomino, also known as dark-eyed cream. Palomino registries have quite a narrow range of acceptable shades of golden coat colour so not all palomino coloured animals will be able to be registered as ‘Palomino’ with the various societies dedicated to the colour.
When the cream gene is present once on a bay base coat, the colour known as ‘buckskin’ or ‘cream with dark points’ is produced; when the base colour is brown the single dilution produces ‘burnt buckskin’ (which is sometimes misidentified as liver chestnut or brown); on a black base the single dilution produces ‘dilute black’ or ‘black buckskin’ which can also be confused with brown, liver chestnut or with fading black. When the cream gene is doubled up (homozygous), a pseudo-albino is produced - a pony with off-white coat colour, just dark enough to distinguish any white markings which may be present. The skin is pink, which may weather to a light tan shade. The eyes are pale blue - in some registries these animals are referred to as ‘blue-eyed creams’. These animals are referred to as ‘cremello’ and ‘perlino’ depending on the base colour. CREMELLO The double-dilution acting on a chestnut base produces an offwhite coat colour and generally an ivory coloured mane and tail. White markings can occur on the face and legs but will be hard to distinguish. The skin is unpigmented (pink) and the eyes are a pale glass-blue. It should be noted that a cremello which has one or both parents grey may also be, genetically, grey; in this case, any progeny may inherit the gene for ‘grey’ and those that do will grey out to become a stark white colour. Cremello can also mask roan and the progeny of a genetic cremello/roan may also be roan. CREMELLO x CREMELLO Cremello CREMELLO x PERLINO Cremello, perlino CREMELLO x CHESTNUT Palomino CREMELLO x BLACK Dilute black, palomino, buckskin CREMELLO x BAY Buckskin, palomino, dilute black CREMELLO x PALOMINO Palomino, cremello CREMELLO x BUCKSKIN Buckskin, palomino, cremello, perlino CREMELLO x ROAN 50% of offspring will be roan, with the base colour determined as above, depending on the base colour of the roan parent. CREMELLO x DUN 50% of offspring will be dun unless the dun parent is homozygous for dun in which case all progeny will be dun, with the base colour determined as above, depending on the base colour of the dun parent. CREMELLO x GREY 50% of offspring will go grey unless the grey parent is homozygous for grey in which case all progeny will go grey, with the base colour determined as above, depending on the base colour of the grey parent. PERLINO The double-dilution acting on a bay, brown or black base produces an off-white coat colour and can be difficult to distinguish from a cremello, although in the perlino the lower limbs, mane and tail may be a shade darker - may be the colour of white coffee. White markings can occur on the face and legs but will be hard to distinguish. The skin is unpigmented (pink) and the eyes are a pale glass-blue. It should be noted that a perlino which has one or both parents grey may also be, genetically, grey; in this case, any progeny may inherit the gene for ‘grey’ and those that do will grey out to become a stark white colour. Cremello can also mask roan and the progeny of a genetic cremello/roan may also be roan. It can be difficult to distinguish between cremello and perlino - confirmation that an animal is perlino possible if, when mated to a chestnut, a buckskin or dilute black is produced. PERLINO x PERLINO Perlino, cremello PERLINO x CREMELLO Perlino, cremello PERLINO x CHESTNUT Palomino, buckskin, dilute black PERLINO x BLACK Dilute black, palomino, buckskin PERLINO x BAY Buckskin, palomino, dilute black PERLINO x PALOMINO Buckskin, perlino, palomino, cremello, dilute black PERLINO x BUCKSKIN Buckskin, perlino, palomino, cremello, dilute black PERLINO x ROAN 50% of offspring will be roan, with the base colour determined as above, depending on the base colour of the roan parent. PERLINO x DUN 50% of offspring will be dun unless the dun parent is homozygous for dun in which case all progeny will be dun, with the base colour determined as above, depending on the base colour of the dun parent. PERLINO x GREY 50% of offspring will go grey unless the grey parent is homozygous for grey in which case all progeny will go grey, with the base colour determined as above, depending on the base colour of the grey parent. PALOMINO (aka CREAM) The ideal ‘palomino’ colour is a golden body colour with snow white mane and tail and is produced when the cream gene is present diluting what would otherwise have been a chestnut coat colour. White markings can occur on the face and legs. However, the coat colour can vary a lot, depending on the base colour which has been diluted. Some redder toned palominos can be mistaken for light coloured chestnuts, and vice verse. However, the shine on chestnut horses is usually red or copper, while the shine on palominos is usually gold or silver. PALOMINO x CHESTNUT Palomino, chestnut. PALOMINO x BLACK Palomino, chestnut, dilute black, black, buckskin, bay, brown PALOMINO x BAY or BROWN Palomino, chestnut, buckskin, bay, brown, dilute black, black. PALOMINO x PALOMINO 25% of offspring will be double dilute, ie, cremello, 50% palomino, 25% chestnut. PALOMINO x BUCKSKIN 25% of offspring will be double dilute (cremello or perlino), 50% will be single dilute (palomino, buckskin or dilute black), 25% will be chestnut, black, bay or brown. PALOMINO x ROAN 50% of offspring will be roan, with the base colour and cream dilution determined as above, depending on the base colour of the roan parent. PALOMINO x DUN 50% of offspring will be dun unless the dun parent is homozygous for dun in which case all progeny will be dun, with the base colour and cream dilution determined as above, depending on the base colour of the dun parent. PALOMINO x GREY 50% of offspring will go grey unless the grey parent is homozygous for grey in which case all progeny will go grey, with the base colour and cream dilution determined as above, depending on the base colour of the grey parent. BUCKSKIN (aka CREAM WITH DARK POINTS) The cream dilution acting on a bay or brown produces buckskin, which may be of varying shades depending on the base colour which is diluted. The colour may be cream with dark points, a bright golden shade with dark points, tan with dark points, or when a brown is diluted, an overall brownish shade with yellow highlights. When black is acted on by the cream dilution, dilute black occurs. Dilute black is difficult to distinguish from fading black. Dilute black ponies are also sometimes mistaken for dark liver chestnut or brown. White markings can occur on the face and legs. These colours are often confused with the various shades of dun, which are produced by the dun dilution. Some animals may in fact inherit and show effects from both the cream dilution and the dun dilution, making identification even more complex. The cream dilution is much more common in Welsh Ponies and Cobs than the dun dilution. Buckskin ponies MAY have a dorsal stripe - but ALL dun ponies have a dorsal stripe. BUCKSKIN x CHESTNUT Palomino, chestnut, buckskin, bay or brown, dilute black, black BUCKSKIN x BLACK Buckskin, bay, brown, dilute black, black, palomino, chestnut. BUCKSKIN x BAY or BROWN Buckskin, bay, brown, dilute black, black, palomino, chestnut BUCKSKIN x PALOMINO 25% of offspring will be double dilute (cremello or perlino), 50% will be single dilute (palomino, buckskin or dilute black), 25% will be chestnut, black, bay or brown. BUCKSKIN x BUCKSKIN 25% of offspring will be double dilute (cremello or perlino), 50% will be single dilute (palomino, buckskin or dilute black), 25% will be chestnut, black, bay or brown. BUCKSKIN x ROAN 50% of offspring will be roan, with the base colour and cream dilution determined as above, depending on the base colour of the roan parent. BUCKSKIN x DUN 50% of offspring will be dun unless the dun parent is homozygous for dun in which case all progeny will be dun, with the base colour and cream dilution determined as above, depending on the base colour of the dun parent. BUCKSKIN x GREY 50% of offspring will go grey unless the grey parent is homozygous in which case all progeny will go grey, with the base colour and cream dilution determined as above, depending on the base colour of the grey parent. DUN Dun coat colour varies according to the base colour and many names are given to the colours produced. The list can be shortened to four however. The Dunning dilution gene acting on chestnut produces red dun; bay becomes yellow dun, brown becomes mouse dun, and black becomes blue dun or grullo. Dun dilution is distinguished from the cream dilutes by a prominent dorsal stripe, face mask and leg barring (known as primitive markings), all of which markings match the mane and tail colour. Two duns mated together will not produce cremello or perlino (unless they are both composite dilutes, ie, also having the cream dilution present in both parents). Dun occurs comparatively rarely in Welsh Ponies and Cobs. TAFFY Taffy is the third dilution and it affects only black pigment. Taffy is a dominant gene, ie, a taffy horse must have at least one taffy parent. They are difficult to differentiate from other colours. Jeanette Gower’s excellent book ‘Horse Colour Explained’ (first published in Australia in 1999 by Kangaroo Press an imprint of Simon & Schuster (Australia) Pty Limited, 20 Barcoo Street, East Roseville, NSW, 2069) has a chapter on Taffy and some excellent colour photographs. GREY Grey is not a colour but a pattern imposed on other coat colours. The underlying base colour is inherited independently of the greying gene, and follows the patterns described previously. Grey eventually masks every other coat colour except cremello and perlino, but it should be noted that cremello and perlino when affected by grey become white not cream in coat colour. Grey is annually progressive, ie, more white hairs appear in the coat every year until the pony is white. Grey is a dominant, ie, a grey pony must have at least one grey parent. The offspring of ponies which are homozygous for grey will all be grey - a homozygous pony must have two grey parents. However, two grey parents, neither of which is homozygous for grey, can still produce non-grey offspring. The basic coat colour of foals expected to go grey should be noted at birth. ROAN
Roan is a
pattern of white hairs imposed on the body base colour but not on
the head and legs which retain the colour natural to that base
colour. White markings can occur on the face and legs. It is a
dominant, ie, a roan pony must have a roan parent or one which was
born roan but which the action of the greying or cream gene has
masked the roan. ‘True breeding’ or homozygous roan is reported to
be lethal - it is thought that homozygous foetus’s are aborted early
in the pregnancy. Roan is sometimes evident at birth and is almost
always showing at the first change of coat, appearing first over the
hindquarter of the foal. Roan is not annually progressive, but the
coat does contain more white hairs seasonally, ie, the coat
generally appears more like the base colour in the winter. Fire
brands on a roan show the solid colour when the pony is in the
whitest phase of its coat. The inheritance of the base colour
follows the patterns described previously; 50% of the offspring of a
mating between a roan and non roan will be roan.
Many terms
have been used to describe roan, eg, strawberry roan, blue roan,
etc, but it is now
Roan is a pattern of white hairs imposed on the body base colourbut not on the head and legs which retain the colour natural to that base colour.’ Elargee Primrose shows this pattern well - she is roan on a dark brown base. Note she is also dappled.
SKEWBALD & PIEBALD The description in the Standard of Excellence says that Welsh Ponies and Cobs may be ‘Any colour except skewbald or piebald’. This terminology, inherited from the parent body, The Welsh Pony & Cob Society (UK), is now rather outdated but in this instance describes horses produced by the tobiano and/or overo genes, either separately or combined, neither of which are known to be present in Welsh Ponies and Cobs. TOBIANO & OVERO The action of both tobiano and overo produces large areas of white on the animal, with underlying pink skin. Tobiano horses usually have white areas which cross the spine and the head will be the base colour with or without normal white markings. The legs are white and the tail is often bi-coloured. Overo horses have irregular white patches which appear to spread horizontally on the body. The legs are the base colour, unless the horse is also showing the effects of the sabino gene, in which case they will show white markings on the lower parts. SABINO The sabino gene, which some authorities believe is responsible for all white leg markings, can also produce large areas of white with underlying pink skin, but generally, these markings will fall within the boundaries laid down by the Society. The gene responsible for sabino markings is very widespread in Welsh Ponies and Cobs. The Society’s rules for acceptable white markings state: ‘The following white markings are acceptable:
TICKING There are two main variations of ticking patterns and they are sometimes confused with roans, but ticking patterns are recessive, ie, they can appear unexpectedly when neither parent showed the pattern. Ticking is a pattern of white hairs which appear in the coat, usually not until the animal is several years old (unlike roan, which is usually obvious at birth or soon after). COON-TAIL TICKING (RABICANO)
This is
associated with horizontal bands on the top of the tail. The
heaviest concentration of
BIRDCATCHER TICKING The white hairs are spread fairly evenly throughout the coat, including on the head and lower limbs - it is often confused with roan but there is no sharp contrast between the amount of white hairs on the body and head and legs as occurs in roan.
Imperial Manika, a bay pony showing Rabicano ticking. Note the concentration of white hairs in the flanks, and the striping effect at the top of the tail. She is also a minimum sabino - note the spearing of the white on the hind legs, and small chin spot.
GLOSSARY PHENOTYPE - the appearance. GENOTYPE - the genetic composition. DOMINANT GENE - a gene which only needs to be present once, ie inherited from one parent, to be apparent in the phenotype. RECESSIVE GENE - must be present twice for the animal to show its effects, ie, must be inherited from both parents. Recessive genes can be carried without their effects showing in the phenotype. HOMOZYGOUS - having a matching pair of genes for a particular colour or trait. Both parents of an animal which is homozygous for a dominant gene will show the effects of that gene, eg, a homozygous grey pony will have two grey parents. However, the offspring of two grey parents is not necessarily homozygous for grey. HETEROZYGOUS - having only one of a pair of genes for a particular colour or trait. © Chris Milvain 2006 |
‘Roan
is a pattern of white hairs imposed on the body base colour but not
on the head and legs which retain the colour natural to that base
colour.’ Elargee Primrose shows this pattern well - she is roan on a
dark brown base. Note she is also dappled. Berry Park Chrysanthemum,
showing extensive sabino markings on a chestnut coat - she also has
a flaxen mane and tail. Ticking is also evident, note that the coat
appears flecked throughout.
white
hairs is in the flanks, fanning upwards. It is a pattern often seen
in Welsh Ponies and Cobs.