Breeding two merles creates a pigment disorder, explains Clark, which affects the color and shape of eye development and inner ear nerve endings. Double Merles can also be blind or have vision problems due to congenital eye defects. Breeding two dogs who carry the merle gene is frowned upon. How much is a double merle border collie worth? These problems are unusual in heterozygous merles (Mm) but more common in homozygous merles (MM). These puppies have excessive white coloration - lack of pigment - and this coloration causes loss of hearing, vision, or any . Heterochromia literally translates to two different colored eyes. Their coats are normally marked and they are not plagued with hearing or vision problems. Because of the complexities of merle inheritance and .

These dogs are sometimes referred to as 'double merle' and sometimes incorrectly referred to as 'lethal white'. Mm: Merle pom dog with one non merle parent. Pet owners cannot tell that their ghost Merle is a Merle Chihuahua at all. [25] Double Merle Pomeranians and any double merle dog is at a much higher risk for severe health problems. The merle gene itself is not a color as such but is a modifier gene that changes the base color of the coat and controls the distribution of pigment.

Unlike in many species, there are very few colour-associated health problems in dogs, and most are avoidable through careful breeding. Breeding two dogs that possess any of the merle variants may produce "double merle" offspring (homozygous) which may be prone to health problems. My own experience owning 4 double merle collies over the past 40 years also does not support infertility, shortened life span or more health problems than single merle or non-merle collies. Merle pattern is not a pattern that occurs naturally in the Poodle dog breed. Ocular defects are directly associated with the double merle coat. These double merle puppies may have health problems because of the double merle gene. Breedign quality collies within the established Standard is a fine challenge. Partial blindness or partial deafness.

Double merles most often come from breeders who don't put much thought in to what genetic combinations they are putting together, and they most often aren't breeding for health. If two merle dogs are bred together, each litter has a 25% chance of being born a double merle.

These include: Diluted or dappled coat. Sadly, they can also pass this on to their offspring, so it is not recommended to breed two merle Great Dane dogs. Because of this, there are a lot of cases of double merles with other issues like epilepsy, and allergies. Puppies that have two copies of this gene have eyes and ears that don't develop properly, leading to lifelong health problems including blindness and deafness. Deformation of eyes is also prevalent among this Dachshund variety. Deafness resulting from a merle to merle breeding. This Border Collie type has a typical double merle coat pattern. Eye defects are also common in double merle dogs - some canines are even affected by . Many dogs will have However, double-merle dogs also have much . It is often believed that deaf/blind dogs are aggressive, unpredictable, untrainable, and prone to other health issues (even a shorter life span). No. They are also particularly seen in White Great Danes. Photo by Dawn H. - used with permission. Health issues associated with the merle allele. Dogs with the double merle gene may be/have: All white in color, or have patches of merle/mottled coloring on the top half of their body - their head, back, and base of the tail. Single-merle dogs are less likely to be affected by such problems and can remain perfectly healthy. All those things that make this Corgi breed unique, unfortunately, have a price. Blindness or deafness usually exist due to lack of pigment in . affecting hearing and vision. Double Merle Great Danes can be beautiful. Double Merle dogs may also have a variety of eye defects that can occur in any color eye. Blindness. The specific issues for Merle Great Danes come when two dogs carrying the merle-gene are bred and produce a litter. Double merles (other than possible hearing and vision loss) are generally quite healthy dogs who live long lives. Funny, they didn't have any problem advertising and lauding these dogs before when I explained just how bad double . Even in the heterozygous (Mm) dog the (M) allele is associated with deafness, eye defects, and problems with the dogs immune system. Double Merle Collie breeders have no problem with their dogs being blind, and they have no problem pulling the wool over your eyes either. . Animals that are "double merle," a common term used for dogs that are homozygous (having two copies) of the merle (M/M) trait, are predominantly white and prone to several health issues. Goal #3: Develop recommended approach to educating breeders, owners and general puppy buying population the . It would be unusual for a double merle to have so much pigment. Double Merle. Merle dogs are known to be vulnerable to a wide range of defects in the eyes and ears. However, an Australian Labradoodle can be smaller or bigger than those reference sizes due to the particular breed of Labrador used for breeding. Missing eyes. Blindness. Melanocytes are pigment-producing cells present in many tissues, including the epidermis, hair follicle, inner ear, and choroid of the eye. Merle Labradoodles are also more prone to sunburn and skin cancer. Often referred to as "M/M," the double merle is a cause for concern because it often produces sick puppies who are inherently deaf or blind. On average, a Border Collie's lifespan is 12 years. Some double merles have completely white coats with little or no merle coloring at all. Double merle dogs have an increased risk of developing health issues. If two such dogs are mated, on average one-quarter of the puppies will be double merles ("double dilute") and a high percentage of these double merle Pomeranian puppies could have eye defects and/or be deaf. MM: Double merle Pomeranian dogs from breeding merle to a merle. This isn't the case for every dog, however. Lucky double merles are born without problems, but many do suffer severe auditory or visual impairments. Double Merle Dogs Have a Slew of Health Issues . However, the merle coat can come with some serious health issues. Because of this, there are a lot of cases of double merles with other issues like epilepsy, and allergies. Many people are unaware, but when two merles (of any breed) are bred together, each puppy has a 25% chance of being born as a double merle. Double merle puppies and dogs have large white patches along their bodies and heads more so than merle dogs. Breeding merle poodles is risky especially if a phantom merle has not been discovered for what it is. The white coloration of double merles is the result of a lack of pigment producting cells (melanocytes). Indeed, merle is a recognised and much sought after colour in some breeds, including the Australian shepherd, the . The pups that do not inherit the gene twice are "normal" dogs. This isn't the case for every dog, however. Congenital eye defects. Genetics of the Merle Pomeranian. Breeding dogs with the merle gene can create offspring with hearing loss, a multitude of eye . It causes hair . Give your dog a DNA test to test for the merle gene. These dogs are called double merles. The unethical practice of breeding double merles is generally condemned worldwide, not only because so many are considered defective and put down at birth by their breeders, but because of the health problems that plague them, namely, partial or complete deafness and blindness. As breeding double merles are risky, double merle dogs can be spayed or neutered to stop the gene from passing. They are likely to suffer from vision or hearing impairments, and in severe cases, the pups are completely deaf or blind. A small eye (microphthalmia) Pupil that is off-center (corectopia) Cataracts. Some of the different merle patterns that exist are: merle, dilute merle, cryptic merle, harlequin. Blindness and other vision impairment. A double merle inherits the merle gene twice. "Merles came from introducing another breed into Cockers to get the color, so no, they are not truly purebred," Vavolo reports. Double merle dogs may have auditory, ophthalmologic, skeletal, and other defects and will transmit a merle variant to all of their offspring. There are a lot of side effects of producing double merle French bulldogs, as these dogs suffer from many health problems. A standard Merle Labradoodle weighs in at 55-60 pounds, and a mini one varies from 15 to 25 pounds. Due to the removal of pigment cells, these dogs can have hearing or sighting problems.

FAQ. The blue eyes sometimes make it more difficult to diagnose eye problems, as well. The average price for Border Collies is around $600, but it's best to prepare a budget for buying a blue merle Border Collie puppy as the cost can go up to $4,500. Australian Shepherd Colors: The Dangers of Double Merle. Double Merle Problems Geneticist Lee Anne Clark says merle-to-merle breedings may be difficult to detect, but health issues in their puppies are usually the result. During this time the ear canal is still closed. Some even end up blind. . They are most often all white or close to it. The merle gene causes changes in the cells that affect pigment or coloring in an Aussie. Dogs with the double merle gene may be/have: All white in color, or have patches of merle/mottled coloring on the top half of their body - their head, back, and base of the tail. WHAT IS A MERLE . During this time the ear canal is still closed. While dogs with double merle coloration are unique and beautiful in appearance, they have an increased risk for certain health problems. The merle pattern is a pale to dark grey coat, covered in darker splotches. ( MM merle Pomeranians have a high risk of health problems, including eye and hearing issues i.e. Where exactly your puppy falls in this range will depend on his breed, pedigree, health and other factors. The following are concerns when breeding merle Labradoodles and the health impact a merle breeding can have: Eye defects. Because this dog has a unique genetic condition, it could result in stunted limbs . Though double merles do not usually have fatal disabilities due to their genetics (negating the term 'lethal'), the implication that double merles are unhealthy compared to normal coloured dogs in their breed has some basis. However, if two merle (Mm) dogs are bred, approximately 25% of the puppies will be double merle or MM. Varied color of the iris. Less extreme but still severe for any dog, double merles could be born blind or deaf. The abbreviation "MM" is also commonly used (genetic shorthand for 2 copies of the merle gene).