What is calcium iodate?
Calcium iodate is the calcium salt of iodic acid, a white, odourless powder that is only slightly soluble in water. The anhydrous form is the one normally used in feed; feed-grade material typically contains about 62–64% iodine.
Iodine is required only in very small amounts, so calcium iodate is often used as a pre-dilution on a carrier, which makes accurate dosing and even distribution in the premix easier.
What does iodine do in animal feed?
- Thyroid hormones: iodine is an integral part of thyroxine (T4) and triiodothyronine (T3), which control basal metabolic rate, heat production and energy use.
- Growth and development: thyroid hormones are needed for normal growth, skeletal development and maturation of the nervous system.
- Reproduction: iodine deficiency is associated with reduced fertility, abortions, stillbirths and weak newborns.
- Newborn animals: classic signs of deficiency in offspring include goitre (enlarged thyroid) and, in piglets and lambs, hairlessness and poor viability.
- Production: adequate iodine supports normal milk production and egg production.
Calcium iodate or potassium iodide?
Potassium iodide (KI) is also used as an iodine source, but it is less stable: in the presence of moisture, heat, light and other premix components it can oxidise and release elemental iodine, which is volatile and can be lost. Stabilised forms of potassium iodide exist for this reason.
Calcium iodate is much more stable during premix storage, pelleting and in mineral licks, which is why it has become the standard iodine source in premixes. Both forms are considered well available to animals.
How is the iodine requirement assessed?
The iodine content of feed raw materials and water depends largely on soil iodine, and many inland regions are naturally low. Some feeds contain goitrogens that interfere with thyroid iodine uptake or hormone synthesis, notably glucosinolates in rapeseed or canola meal and other brassicas; when such feeds are used, the iodine requirement increases.
Iodine passes readily into milk and eggs, so maximum permitted levels are lower for dairy cows and laying hens in some jurisdictions, including the EU. Nutritionists set the supplemental level according to species, production stage and the use of goitrogenic feeds. Local regulations and the product label always prevail.
Quality criteria
- Guaranteed iodine content, verified by analysis, for the pure product or the pre-dilution.
- Homogeneity of the pre-dilution and of the premix at low inclusion rates.
- Undesirable substances: lead, cadmium and arsenic within legal limits.
- Fine particle size and good flowability for even distribution.
- Certificate of analysis (CoA) and lot traceability.
CTF Premix and calcium iodate
Calcium iodate can be included in CTF Premix's mineral and vitamin-mineral premixes according to the customer's formulation, with the iodine level matched to the species and the use of goitrogenic raw materials. Premixes are produced at our Ankara facility under ISO 9001:2015 and GMP, with micro-ingredient mixing procedures, and every 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.