Hi there
My understanding of the staining, both tear and saliva is as follows
Red yeast makes the stains red to rusty red in colour.
This yeast can also be quite smelly.
The enzyme from which the yeast grows is formed by the bacteria in the tears "eating" (metabolising) the iron content in the tears as it starts to rust (oxidise).
The degree of staining is ultimately related to the extent of tearing. So it follows that if you were able to keep the fur dry you would have no staining as the bacteria needs a damp and warm environment.
Please do not worry about the bacteria in the tears- it is perfectly natural, safe and does not lead to infection
Possible solutions
Distilled water/vinegar/TUMS
Tears are about 7.4 ph which is close to neutral (7.0 ph) but very slightly alkali.
The bacteria needs a ph value close to neutral to metabolise the iron.
Distilled water will have less iron so there is less for the bacteria to metabolise. The success depends on the amount of iron in the rest of the iron (the key source of iron and mineral intake).
Rain water will have low mineral content.
Cider vinegar in the drinking water might work by making the ph value of the tears more acidic, thereby preventing the bacteria from metabolising the iron- I doubt that it is acidic enough to actually kill the bacteria.
TUMS etc- works as above but makes the tears more alkali.
I do not think that TUMS or vinegar should be used in the long term but are probably ok in the short term.
Diet
This can work on a number of levels
Dogs are often intolerant to processed grains and many of the bulking agents/preservatives in store food- not part of their natural diet. Higher quality diets (such as home cooked) are likely to have fewer of these- additionally green vegetables can help to oxidise the iron inside the body before they enter the tears. The bacteria is unable to metabolise and tap into the energy in the iron if it has already oxidised.
There are a number of food supplements that are designed to oxidise the iron. For many owners these are easier to use than diet tweaks. Some are also designed as nutrient supplements
two of the best that I know of are
Angels Delight by Bichon Hotel
Tear Stain Supplement by Naturvet
These types of tear stain removers are my prefered choice- There are others out there but I have not used them- Make sure that you can see the ingredient list before using anything that calls itself a natural tear stain remover.
Antibiotics/Angels Glow/Angels Eyes/Clear Tears
These work by killing the bacteria in the tears but they are not without risk. The over use of antibiotics can lead to resistance in bacteria meaning that other antibiotics used for more serious issues will not work- this can affect the health of dogs and humans. Tetracycline is the most commonly prescribed by vets but some also prescribe tylosin. Tylosin is found in
Angels Eyes/
Angels Glow/Clear tears
These work quickly but should only be used briefly and might affect other medications. They may also kill the good bacteria in the gut- this last point is very important- tylosin can prevent certain animals from extracting nutrients form food in the intestines- leading to death, for example horses
All antibiotics are prescription only-
all OTC products containing tylosin are illegal- even if they are sold in your local pet store.
Vaseline etc
Not sure but I think this stops the stains from soaking into the hair rather than changing the relationship between the bacteria and iron.
Creams and pastes
Many of these use boric acid and acetic acid in an emollient base to clean and kill the bacteria
Home brew pastes and remedies
These are multiple, Some use antacids in paste some are hydrogen peroxide based. The latter brews worry me as if used incorrectly they could cause great harm.
Degrees of tearing and staining
Can be the result of
Teething- inflames the gums and can put pressure on the tear ducts- preventing their normal function as a recycling center.
Blocked or under developed ducts- speak to your vet
Excessive licking- look at diet and fleas, anxiety etc- try Neem shampoo
Fleas/ticks
Infection and ear infections- speak to your vet
Pollen and allergens- seasonal
Stray hairs and other irritants
Why do some dogs start staining late in life or stop staining?
No one really knows....
Now hopefully the above will help you to decide which solution suits your dog- you might find that a combination of them works for you. What works for one person might not work for another.
Please let me know if I missed anything.
Regards D
