The National Horseracing Authority (NHA) wishes to remind trainers of the guidelines relating to the administration of Vitamin B12 and cobalt-containing products in the period leading up to race day. 

Cobalt is a naturally occurring trace element and a structural component of Vitamin B12 (cobalamin). A normal racing diet provides more than sufficient cobalt to meet a horse’s daily requirement of approximately 1 mg. There is no documented cobalt deficiency in horses, nor any recognised condition for which cobalt supplementation is indicated. 

Internationally adopted cobalt thresholds, which are in place to protect horse welfare and the integrity of racing, are 0.1 micrograms per millilitre (100 ng/ml) in urine and 0.025 micrograms per millilitre (25 ng/ml) in plasma. 

These thresholds were established following extensive international race-day population studies. Untreated horses typically show urine cobalt concentrations of 2-5 ng/ml, while horses on cobalt-fortified feed are usually around 8 ng/ml. 

Trainers are reminded that many registered oral and injectable supplements, including Vitamin B12 products, contain cobalt and may increase blood and urine cobalt levels above the thresholds for varying periods. Withdrawal times depend on dose, route of administration, frequency of use, and whether multiple products are administered concurrently. 

Key points:

• Injectable cobalt or Vitamin B12 supplements offer no nutritional advantage, as incorporation of cobalt into Vitamin B12 occurs naturally in the horse's hindgut.
• The simultaneous use of multiple products containing cobalt and/or Vitamin B12 significantly increases the risk of exceeding the threshold.
• Products marketed as "high dose" or "forte" require longer withdrawal periods.
• Oral and injectable products differ in bioavailability and withdrawal times and must be managed accordingly.
• Unregistered, inadequately labelled, or internet-marketed products claiming performance enhancement or being "undetectable" pose a serious risk and are strongly discouraged. 

Supplemental cobalt from any source, including Vitamin B12 or cobalamin-containing products, should not be administered within at least two clear days prior to race day. Higher or repeated doses may require longer withdrawal periods. 

The administration of supplements constitutes a treatment and must be recorded in the Veterinary Treatment Register (VTR) on the day of administration. Supplements must only be used at the manufacturer’s recommended dose and frequency. Trainers are encouraged to consult their veterinarians to ensure supplementation is appropriate and limited to the horse’s established nutritional requirements. 

Failure to manage the use of Vitamin B12 and cobalt appropriately may result in a breach of the Rules of Racing and may have welfare implications for the horse. 

Any questions or for further clarity on the above, please contact the NHA Veterinary Department at This email address is being protected from spambots. You need JavaScript enabled to view it. or via WhatsApp on +27 66 471 4527.