It is very important to measure Calf IgG levels soon after birth (24-48 hrs old).
Up to 40% of Newborn Calfs have partial or total failure of IgG Passive Transfer from the cow due to premature lactation, deficient suckling, malabsorption, or low IgG levels in the cow's colostrum.
Color intensity on Test Line is proportional to Calf IgG concentration.