Understanding B-vitamins

Horses that receive plenty of fibre in their diet create their own supply of B-vitamins, which are synthesised by the micro-organisms present in the hindgut. As long as there is plenty of fermentation of fibre in the intestinal tract, the supply of B-vitamins will be plentiful.

However, if this internal manufacture (and absorption) is disrupted in any way, then a deficiency in several of the many B-vitamins that exist can occur and supplementation may be beneficial.

Disruption to the fermentation of fibre in the hindgut can take place for a number of reasons: a low-fibre diet being a prime example. Other instances include any undue stress, such as when horses don’t travel well, or through illness, rapid growth or following surgery or heavy antibiotic use. Antibiotics can do a good job of wiping out some of the microbial population in the hindgut.

Competition horses and racehorses are examples of horses that may well be deficient in B-vitamin production: a compromised gut micro flora due to a low-fibre, high-starch diet on top of the stresses of training and the excitement of competition or race day. Indeed, some scientific studies have proven this to be true.

Other candidates for B-vitamin supplementation are older horses with poor teeth that cannot chew their fibre well, or horses recovering from illness or surgery that have had a hindgut disturbance.

Breakdown of B-vitamins

• Vitamin B12: vital for enzyme function and for fat, protein and carbohydrate metabolism. Also required for the formation of blood cells and amino acids
• Folic acid: works closely with vitamin B12 to produce red blood cells and haemoglobin
• Vitamin B6: (pyridoxine) is essential for energy production, nervous system activity and for blood production
• Vitamin B1: (thiamin) is also required for fat and carbohydrate metabolism
• Vitamin B2: (riboflavin) again vital for protein and carbohydrate metabolism
• Niacin: supports healthy skin and digestion, and again important in energy transfer. Signs of deficiency include a loss of appetite and diarrhoea
• Pantothenic acid: used in the production of antibodies and energy metabolism
• Biotin: again necessary for energy and protein metabolism and shown also to have a positive effect on hoof condition at high levels (15mg per day for at least nine months)

This feed forum feature was first published in Horse & Hound (28 October, 04)