Table 3.

Required and recommended iodine supplementation of feed of cattle, pigs, and poultry in the US, UK, and Germany (mg/kg feed dry matter)¹.

Item	US (NRC, 1985, 1996, 1998, 2001, 2005)	UK (AFRC, 1981)	Germany (GfE, 1995, 1999, 2001, 2003, 2006)
Dairy cattle	0.50	0.80	0.50
Growing calves/bulls	0.50	0.12	0.25
Sows	0.16	0.50	0.60
Growing pigs	0.16	–	0.15
Laying hens	0.32-0.49	–	0.50
Broiler chickens	0.35	–	0.50

US NRC = National Research Council (NRC) of the United States; GfE = Gesellschaft fur Ernahrungsphysiologie; AFRC = Agricultural Food Research Council.

¹Data for sheep with 0.100 to 0.80 mg/kg dry matter (NRC, 1985) and goats with 0.30 to 0.80 mg/kg feed dry matter (GfE, 2003) were not included above.