dietary vitamin D3 at concentrations similar to the dietary
requirement of nursery pigs (100 to 250 IU/kg of the diet),
but no research has looked at supplementing vitamin D3
in alternative forms as discussed in the current studies or
at levels above those typically supplemented in commercial
diets. Comparing results in the present experiments to
those previously discussed is challenging due to the difference
in concentration of vitamin D3 supplementation.