What is riboflavin?
Riboflavin is made up of a flavin (isoalloxazine) ring linked to ribitol, a sugar alcohol. It is an orange-yellow crystalline substance with low solubility in water and strong sensitivity to light. In the body it is converted into flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD).
Today feed riboflavin is produced mainly by fermentation with selected microorganisms, such as the fungus Ashbya gossypii or Bacillus subtilis strains. Cereals and oilseed meals are relatively poor sources, so supplementation is standard in pig and poultry diets.
What does riboflavin do in animal feed?
- Energy metabolism: FMN and FAD are carriers in oxidation–reduction reactions of the respiratory chain, fatty acid oxidation and amino acid metabolism.
- Poultry: young chicks are sensitive to deficiency, which causes 'curled-toe paralysis' and poor growth; in breeders, riboflavin status influences hatchability and embryo development.
- Pigs: important for growth and reproduction; sow diets are supplemented to support normal reproductive performance.
- Ruminants: rumen microbes normally produce sufficient riboflavin; dietary needs mainly concern pre-ruminant calves on milk replacer.
- Fish and pets: included in complete feeds as part of the B-vitamin package.
Riboflavin 80% and other grades
- Riboflavin 80% feed grade: a spray-dried or granulated product containing about 80% riboflavin, the rest being fermentation solids and processing aids. The granulation reduces dust and electrostatic charging and improves flowability and distribution in premixes.
- Crystalline riboflavin (about 96–98%): a fine, highly concentrated powder that tends to be dusty and electrostatic; offered in feed and higher grades and used where a concentrated source is needed.
- Riboflavin 5'-phosphate sodium: much more water-soluble, used in liquid and drinking-water products.
- Conversion: to supply 1 g of riboflavin, about 1.25 g of an 80% product is needed. Always calculate on the declared riboflavin content of the actual lot.
How is the riboflavin supply assessed?
Nutritionists set riboflavin levels per kilogram of feed by species, age and production stage, with higher attention for young poultry and breeders. Losses during pelleting are generally moderate, but light exposure and long storage of premixes reduce activity. The contribution of raw materials is usually given little weight because it is low and variable. Local regulations and the product label prevail.
Quality and handling criteria
- Assay of riboflavin on the declared basis and a certificate of analysis (CoA) for each lot.
- Physical form: granule size, low dust and good flow, important for accurate dosing and worker comfort.
- Protection from light: riboflavin breaks down in light, so it is stored in opaque, closed packaging in a cool, dry place.
- For fermentation products, compliance with the safety requirements for the production strain; in the EU, for example, products from genetically modified strains must be free of viable cells of the production strain.
- Compatibility in premixes: relatively stable compared with vitamins A, D3 and K3, but still affected by alkaline conditions and reducing agents.
CTF Premix and riboflavin
Riboflavin, typically as an 80% feed grade, can be included in CTF Premix's vitamin, vitamin-mineral and custom premixes according to the customer's formulation, with the declaration made on a riboflavin basis. Production takes place at our Ankara facility under ISO 9001:2015 and GMP; each lot has a certificate of analysis and lot traceability.
This page is for general information. Inclusion rates and product choice should be decided with a nutritionist, taking into account the species, the feed formulation and the applicable regulations.