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Animal charities: RSPCA
Day-blindness
Labrador coat colours
Are you having difficulties logging in to your dog’s profile?
Animal charities: RSPCA
The Royal Society for the Prevention of Cruelty to Animals (RSPCA) is an animal welfare charity which began in 1824 and operates in England and Wales to prevent cruelty to all types of animals. The RSPCA aim to prevent any animal suffering by offering advice and education on caring for animals, and campaign for animal rights and welfare; serving to change laws to better protect animals, and prosecute those who have mistreated them.
The RSPCA rescue pets, wildlife and farm animals if they have had an accident or injury, or been badly treated or abandoned. Members of the public can contact the RSPCA if they find an animal in need of rescue or report any concerns of animal cruelty or neglect (over one million calls were made to the RSPCA in 2010).
The RSPCA treated over 211,000 animals, rescued and collected over 130,000, and rehomed over 64,000 in 2010. Throughout England and Wales, the RSPCA has 166 branches, 16 regional animal centres, 4 animal hospitals, and 4 specialist wildlife centres. These facilities enable the RSPCA to help and treat animals, and if required, take them into their care and provide specialist treatment and rehabilitation until they are ready to be rehomed or released back into the wild.
When pets are ready to be rehomed, they can be viewed online and/or visited in person at one of the RSPCA’s centres. To make sure that pets and owners are suitably matched, potential new owners are asked spend time with the pet at the centre before taking them home. A trained RSPCA volunteer will pay a follow up visit to the new home to make sure that the rehoming has been a success and both pet and owner are happy. For more information from the RSPCA on caring for dogs and dog welfare, please visit http://www.rspca.org.uk/allaboutanimals/pets/dogs.
The RSPCA also operate and support animal welfare projects, campaigns and training courses in Europe, East Asia and southern Africa, and provide aid in emergency situations (e.g. oil spills) internationally. The RSPCA International’s recent work involving dogs includes providing training on dog population and dog shelter management in Turkey, and training on animal protection legislation to reduce the roadside selling of puppies in Malawi, Africa.
To visit the RSPCA’s website and find out more about the charity, please click here.
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Day-blindness
Hemeralopia, also known as "day blindness", is an extremely unusual condition affecting both dogs and people which is characterised by the inability to see clearly in bright light. Affected individuals demonstrate photo aversion (the avoidance of light), whilst their night time vision is unaffected. In dogs it is characterised by degeneration of the cone cells at the retina in the back of the eye which are responsible for colour vision, particularly in bright light. The rod cells responsible for vision in dim light are unaffected and thus affected dogs can see normally in darker conditions. The clinical signs can vary from clumsiness to complete blindness in bright light, and are usually apparent immediately when dogs pass from a dimly lit environment to a bright one. At present there is no cure for the disease, although the symptoms can be improved in people by wearing sunglasses, and light filtering contact lenses have been used to treat dogs.
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Labrador coat colours
One of our black Dogslife dogs has recently had a litter of puppies. Could she have had yellow puppies in spite of being mated to a black sire? Could a yellow dog have chocolate pups? The genetics of yellow, black and chocolate coat colours is relatively simple. Some of the more complicated colour differences (for example cream vs yellow vs fox red) are not really understood.
The colour in your dog’s coat comes from pigment molecules called melanins which belong to the same family as the pigment that develops when we tan in the sun. The black and chocolate coats result from the presence of eumelanins and the cream, yellow and red colours (including the darker fox red) are phaeomelanins.
Synthesis of melanin starts from tyrosine, one of the essential amino acids in our diet. Tyrosine is converted through a series to steps to the various melanins. If any of the steps are blocked the next steps can’t happen and the pigment isn’t formed.
If the conversion of tyrosine to intermediate 1 is blocked, the dog would have a pure white coat, like an albino rabbit or mouse. This has never been reported in dogs. If the conversion of intermediate 1 to intermediate 2 (Step A) is blocked, the dog will have a pale coloured coat (cream, yellow or red) caused by the presence of phaeomelanins, because it is not possible to form the darker pigments without that step. However, if conversion of intermediate 2 to eumelanin is blocked (Step B), the dog will have a chocolate brown coat, because the presence of intermediate 2 allows some dark pigment to be deposited in the coat hairs, even though the full amount of eumelanin isn't made.
These two critical steps, Step A and Step B, are carried out by proteins that are encoded by genes in the dog’s DNA. If there is a change in the gene that is responsible for Step A so that that step can’t happen, the dog will be pale coloured. If there is a change in the gene for Step B, the dog will be chocolate. So in the simplest form, two genes are involved in coat colour.
Dogs (and all other living organisms other than bacteria) have two copies of all genes, one inherited from the sire and one from the dam. The steps will only be blocked if both copies of the gene are changed (mutated). The gene for step A is called the Expression (E) gene. The version of the gene for dark coat colour is called E and the version for light colour is e. Light coloured dogs inherit the e variant from both parents, and are said to be ee genotype. Dark coloured dogs inherit at least one E and have either the EE or Ee genotype. So any dog that is ee will be light coated: step A will be blocked and the only pigment will be yellow/red phaeomelanin.
If a dog is Ee or EE, its coat colour depends on the second gene, called the Black (B) gene. Chocolate dogs fail to carry out Step B and have two non-functional copies of the Black gene, called bb. Black dogs are able to carry out that step so they must have at least one copy of the functional gene, BB or Bb.
We can summarise all the possibilities:
So to get back to the original question, could two black dogs have yellow puppies? The answer is yes, it is possible, depending on the genotype of each dog. In fact, this mating could produce black, yellow and chocolate puppies, for example if the genotypes were those shown below.
But could two yellow dogs have black or chocolate puppies? No, that couldn’t happen. Yellow dogs must be ee for the Step A gene, so all their puppies will also be ee (they must get the e variant from both parents because that’s all there is) and hence yellow. The yellow colour should breed true, but the black colour will only breed true if both dogs are EE BB.
Some companies now offer a DNA test that will determine whether a black dog is EE or Ee, BB or Bb. They can also tell if a yellow dog (who must be ee) is BB, Bb or bb. You might be able to tell whether your yellow dog is bb or BB/Bb. Take a look at the nose - if it’s black your pup should be BB or Bb and if it’s pink your dog is probably bb. There are also lots of websites that show all possible combinations of parents and offspring coat colour.
This is the simplest way of looking at Labrador Retriever coat colours. It becomes more complicated when looking at the genetics of more subtle colour differences. For example the difference in the light coat colour, from pale cream to fox red, is probably determined by genes that are involved in the steps between Intermediate 1 and phaeomelanin, resulting in production of different variants of phaeomelanin pigment. In other dog breeds, different genes are known to affect white and black patterns, brindle patches, dark legs and muzzles and other colour variants.
Our recent Dogslife mum produced a litter of eight bouncing black pups so one or both parents is most likely EE BB. We are hoping the pups will join Dogslife with their new owners so we can follow two generations of Dogslife dogs.
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Are you having difficulties logging in to your dog’s profile?
Don’t worry! Dogslife are here to help. If you have entered your email address and password to the ‘Member Login’ box (pictured to the right) on the Dogslife homepage and clicked ‘Submit’, but have not reached your dog’s profile page, you will be taken to another login screen to enter your login details again (as pictured below right).
If you are still unable to login (and you are sure the email address entered is the same one we contact you on), simply click on the ‘Forgotten your password?’ link at the bottom of the page (where you will be asked to enter your email address) and an email will be sent to you with a link to reset your password. The ‘Forgotten your password?’ link has also been added to the ‘Member Login’ box on the homepage if you can’t remember your password to begin with. If the email doesn’t arrive shortly after you requested it, check you junk mail folder to make sure the email is not in there by mistake.
After resetting your password you should be able to access your dog’s profile without any further difficulties (be sure to keep your new password safe and type it into the password box when logging in especially if you don’t normally have to type the password in the box because it appears there automatically), but please do not hesitate to email us at info@dogslife.ac.uk with further information on what is happening if you still cannot login and we will do our best to help you access your dog’s profile page as soon as we can.
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There will be a prize draw at the end of September so don't forget to come back to Dogslife (www.dogslife.ac.uk) and update your dog's record to be in with the best chance of winning!
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