The B12 vitamin is an essential vitamin for dogs. A lack of B12 can lead to health problems such as anemia and eventually gastrointestinal disease. Vitamin B12 is not a vitamin commonly found in plants or vegetation. The most abundant source of vitamin B12 is meat products, specifically organ meat. Organ meat is not a typical ingredient in dry or canned dog food. In fact, most commercially produced dog food contains mainly cereal. That’s not a bad thing for most dogs, since dogs obtain a great deal of their energy from carbohydrates. However, for dogs that are not getting enough B12, a B12 vitamin supplement may be necessary to improve your dog’s health.

NOTE: B12 injections are also discussed under Exocrine Deficiency Sufficiency (EPI) so another possible discussion for your veterinarian.

Vitamin B12 Performs an Important Role in Your Dog’s Body:
Vitamin B12, along with iron and folic acid, work to ensure that a dog’s nervous system functions properly. It is also needed for normal cell growth. When your dog is deficient in vitamin B12, he may become sluggish. It is likely he will not want to go for walks or to play. Vitamin B12 helps maintain a dog’s normal energy level. Another symptom of B12 deficiency is a lack of appetite. Your dog may not want to eat, no matter what kind of food you put in front of him.
If your dog exhibits these symptoms, the cause could be lack of sufficient levels of vitamin B12, or it could mean that your dog has inherited or developed a condition in which he does not absorb the vitamin B12 he is receiving through his normal diet. This is a very common condition in certain breeds, including giant Schnauzers as well as beagles and border collies. In these dogs this condition is almost always inherited (genetically passed on), and can occur at different ages, depending on the breed. In this situation, your dog may exhibit an additional symptom: he may experience weight loss or fail to gain weight if he is a puppy. Like dogs that are deficient in vitamin B12, these animals will be lethargic. They may lose weight. If not treated, these dogs can begin to experience gastrointestinal disease.
If your dog exhibits these symptoms, certain laboratory tests can determine whether a vitamin B12 deficiency or malabsorption is the cause. A complete blood work up, including a white blood cell count and serum check will be performed. Most veterinarians will also do a urinalysis, to look at white blood cell counts there as well.

Treating a Vitamin B12 Concern:
Treatment for both vitamin B12 deficient dogs and those with the genetic tendency to not absorb it, is a B12 vitamin supplement. Most supplements are water soluble and can be given to your dog with a syringe, injecting it into his mouth. In severe cases the B12 may have to be administered through an injection directly in your dog’s hind leg. This allows the vitamin to be more readily absorbed by the body.
If your dog is healthy, but you want to increase his appetite or energy level, you can also give your dog a vitamin B12 supplement. However, in this case a multivitamin containing complex B vitamins may be the best choice.

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