Utilisation of iodine from different sources in pigs

Area of Science:

• Animal Nutrition
• Trace Mineral Metabolism

Background:

• Iodine is an essential trace element crucial for thyroid hormone synthesis and overall animal health.
• Dietary iodine utilization can be influenced by the source and chemical form of iodine supplementation.
• Understanding iodine bioavailability is vital for optimizing animal diets and preventing deficiencies.

Purpose of the Study:

• To evaluate the utilization and bioavailability of different supplemental iodine sources in growing pigs.
• To compare the efficacy of potassium iodide (KI), ethylenediamine dihydroiodide (EDDI), iodine humate (HUI), and an oil-based product (P) as iodine supplements.
• To assess the impact of supplemental iodine on iodine excretion patterns in pigs.

Main Methods:

• Balance experiments were conducted using growing pigs fed a standard ration supplemented with various iodine sources.
• Iodine utilization was determined by measuring iodine intake and output (urinary and fecal excretion).
• Statistical analysis (P < 0.01) was used to compare the differences in iodine utilization among the treatment groups and controls.

Main Results:

• Overall iodine utilization from the basal ration was 48.8%.
• Supplemental iodine sources showed varying utilization rates: KI (93.6%), EDDI (92.6%), P (90.7%), and HUI (67.9%).
• Iodine utilization from KI and EDDI was significantly higher than from HUI and P. HUI exhibited the lowest bioavailability, likely due to humate binding.

Conclusions:

• Potassium iodide (KI) and ethylenediamine dihydroiodide (EDDI) are highly bioavailable iodine sources for growing pigs.
• Iodine humate (HUI) demonstrates significantly lower iodine bioavailability compared to KI and EDDI, potentially due to its chemical matrix.
• Optimizing iodine supplementation requires careful consideration of the iodine source to ensure adequate nutrient supply and minimize excretion.