Reference Interval
| Cobalamin (Vitamin B12) | Folate (Vitamin B9) | |
|---|---|---|
| Canine | 251 – 908 ng/L | 7.7 – 24.4 µg/L |
| Feline | 290 – 1,500 ng/L | 8.5 – 26.9 µg/L |
Serum Cobalamin (Vitamin B12) and Folate (Vitamin B9)
Sample Requirements & Shipping information
- 0.5 mL of serum; fasting (8 to 12 hours) is recommended.
- Serum folate shows limited stability at room temperature. Therefore, serum samples for folate analysis should be kept in a refrigerator (4°C) for no longer than 48 hours.
- If samples are being held for more than 48 hours, serum can be stored frozen at -20°C for up to 1 month.
Turnaround
- 3-5 business days after receipt of samples.
Interpretation
Cobalamin
Absorbed in the distal small intestine (specifically the ileum). Values below the reference interval are often seen in patients with disease affecting the distal small intestine, exocrine pancreatic insufficiency (EPI), or small intestinal dysbiosis. Recent supplementation is expected to increase cobalamin concentrations. There is no proven significance of values exceeding the reference interval.
Exocrine pancreatic function should be evaluated (by measuring trypsin-like immunoreactivity) in dogs and cats with cobalamin deficiency as cobalamin absorption is dependent on exocrine pancreatic function.
Folate
Absorbed in the proximal small intestine. Values below the reference interval are consistent with disease affecting the proximal small intestine. Values above the upper limit of the reference interval may indicate small intestinal dysbiosis but can also be caused by recent supplementation. Small intestinal dysbiosis usually occurs secondary to chronic enteropathy or other gastrointestinal disorders. Any treatment should be based on the patient’s clinical presentation and should focus on treating these underlying causes.
Note: Dietary deficiency of cobalamin and folate is highly improbable and even starvation of several weeks’ duration does not cause serum cobalamin and folate to become subnormal in dogs. Therefore, subnormal serum concentrations of cobalamin typically reflect a state of malabsorption and should be treated. Supplementation protocols are described on the cobalamin information page). Folate supplementation recommendations can be found on the folate information page.
It is important to note that, not all intestinal diseases causing malabsorption of vitamins are sufficiently severe and/or long-standing enough to deplete body stores of either vitamin. Therefore, not all dogs and cats with intestinal diseases have abnormal serum cobalamin or folate concentrations.