Cobalamin (Vitamin B12) for Dogs

Cobalamin, also known as vitamin B12, is one of the eight B vitamins. B vitamins are essential for various metabolic processes in both humans and canines. B12 in particular is important for healthy nervous system and brain function, among others. 

Cobalamin isn’t produced by plants or animals but by bacteria. Therefore, dogs cannot synthesize this vitamin, but they can get all the cobalamin they need from their food or supplementation.

So, what exactly does cobalamin do in the body? How much of this vitamin does your pup need, and how can you tell if they might need a supplement? Are dogs more prone to cobalamin deficiency or cobalamin overdose? Let’s dive in to find out!

What does cobalamin do for dogs? A lot! Cobalamin is vital to your dog’s well-being. For starters, it aids in red blood cell production. And when there’s a sufficient amount of red blood cells in your dog’s blood, oxygen and nutrients are distributed throughout their body effectively. 

Cobalamin also plays a crucial role in the nervous system. It helps create myelin, the protective layer that coats nerves. Adequate myelin supports brain and spinal health, gives your dog control over physiological functions, and keeps their nervous system working properly.

Additionally, cobalamin contributes to cell growth and the breaking down of fats, carbohydrates, and proteins. 

Some dog breeds have an inherited disorder that makes it difficult for them to absorb cobalamin. For these dogs, supplementing with cobalamin is usually indicated. This is also the case for those with exocrine pancreatic insufficiency (EPI).

So how much cobalamin does your dog need? According to the National Research Council (NRC), the daily recommended allowance of cobalamin for an adult dog weighing 33 pounds consuming 1,000 calories per day is 9 mcg.

According to the Association of American Feed Control Officials (AAFCO), dogs of all life stages need a minimum of 0.007 mg of cobalamin per 1,000 kcal ME. Additionally, commercial dog food should contain a minimum of 0.028 mg of cobalamin per kg of dry matter. Note that this refers to per kg of diet, not per kg of body weight.

If your dog is suffering from inherited selective cobalamin malabsorption, chronic enteropathies, or EPI, your vet may recommend 250 to 1,000 mcg of cobalamin, taken orally once a day.

As mentioned earlier, our canine companions cannot synthesize cobalamin, and so they must obtain it through their food. Farm animals are often supplemented with cobalamin in their feed. Some plant foods, such as certain mushrooms and seaweed, contain some cobalamin. 

Food sources of cobalamin for dogs include:

• Muscle meats
• Organ meats
• Poultry
• Fish
• Eggs
• Dairy products
• Kelp

Note that cobalamin can be easily destroyed by heat, light, and oxidation.

A dog with cobalamin deficiency may have one or more of the following symptoms:

• Lethargy
• Loss of appetite
• Change in eating habits
• Dull coat
• Loss of muscle mass
• Weight loss
• Weakness
• Diarrhea
• Loss of interest in playing
• Failure to thrive
• Mental dullness
• Seizures

Cobalamin deficiency in dogs primarily occurs when there is a problem with cobalamin absorption. Conditions that can cause cobalamin deficiency include:

• Inflammatory bowel disease (IBD) 
• Exocrine pancreatic insufficiency (EPI)
• Pancreatic cancer
• Chronic enteropathy
• Alimentary lymphoma
• Small intestinal dysbiosis
• Inherited selective cobalamin malabsorption

Inherited selective cobalamin malabsorption, which is known as Imerslund-Gräsbeck syndrome (IGS) in humans, makes a dog genetically predisposed to have difficulty absorbing cobalamin. This condition is rare but has been reported in several breeds, including:

• Border Collies 
• Beagles
• Chinese Shar-Peis
• Giant Schnauzers
• Australian Shepherds

Treatment of cobalamin deficiency

When left untreated, cobalamin deficiency can potentially lead to serious health problems. Fortunately, treatment is widely available, inexpensive, and effective.

The recommended treatment for cobalamin deficiency is cobalamin supplementation. Dogs with an inherited or genetic condition can often be treated with oral supplementation, while those with an intestinal disease respond best to subcutaneous injection. Any underlying medical issues would need to be treated.

Depending on the dog’s weight and condition, oral dosing ranges from 0.25 to 1 mg daily, while subcutaneous dosing ranges from 250 to 1,200 mcg weekly or monthly.

Genetic testing is also available for breeds that are prone to inherited selective cobalamin malabsorption. 

For more information, check out our guide Failure to Absorb Vitamin B12 in Dogs.

Should you be worried about vitamin B12 toxicity in dogs? Since cobalamin is water-soluble, any excess amounts are excreted through the kidneys and flushed out with urine. Cobalamin is very safe and overdose has never been reported in any species.

Cobalamin supplements for dogs come in tablet and injectable forms. They are effective in treating cobalamin deficiency caused by IBD, EPI, chronic enteropathy, and other conditions. Dog breeds that benefit most from cobalamin supplements are Giant Schnauzers, Chinese Shar-Peis, Border Collies, Beagles, and Australian Shepherds, as they have a genetic predisposition to selective cobalamin malabsorption.

While cobalamin is non-toxic to dogs, it should not be given to canines with known hypersensitivity to it or cobalt. It’s also important to note that some drugs can affect the absorption of cobalamin, including neomycin, potassium chloride, para-aminosalicylic acid, and colchicine.

You may be wondering, how do I know if my dog needs B12? Most commercial pet foods are supplemented with cobalamin. Dogs who do not have a condition that affects their ability to absorb it and who eat a complete and balanced diet likely won’t need supplements. However, if you think your pup might benefit from a supplement, talk to your veterinarian.  

As you can see, cobalamin or vitamin B12 is essential to canine health. While cobalamin overdose is unheard of because it is non-toxic and water-soluble, cobalamin deficiency can happen due to a number of reasons, including certain diseases and genetic defects.