Dairy processors report benefit of reduced iodine levels in feed
A recent industry-wide initiative to reassess the iodine nutrition of lactating dairy cows is having a beneficial effect on milk iodine concentrations, Teagasc has said in a recent research update.
Until spring 2017, the animal compound feed industry in Ireland had adopted using 60mg iodine per day as the ‘normal’ supplementation rate rather than 12mg iodine per day as originally recommended.
In January 2017, all manufacturers of compound feed in Ireland were requested to revert to the recommended rate of 12mg/d.
In research involving its dairy herds in Moorepark, Teagasc varied the supplemental iodine intake and milk iodine concentrations of the herds.
Herd 1 and Herd 2 were receiving close to the target iodine supplementation rate, but Herd 3 was receiving surplus supplemental iodine.
Consequently, the bulk tank milk for Herd 1 and Herd 2 was well below the upper limit for milk iodine concentration, but Herd 3 was exceeding the upper limit.
Teagasc has said that the results clearly indicate that it is feasible to maintain milk iodine concentration at between 20 and 150μg/kg by providing approximately 12mg iodine per day.
It also said in the update that Initial feedback from processors in 2017 indicates that the iodine specifications for the Infant Milk Formula market have been easier to achieve than in previous years.