Old Standards and New Standards for Passive Transfer
Just for review the old standards used since the 1980's to define "successful" passive transfer have been5.2 grams per deciliter (g/dl) or10 grams per liter (g/l).
In a talk given to the Dairy Calf and Heifer Association, Jason Lumbard DVM with USDA-APHIS reviewed a new set of proposed standards.
Categories IgG Levels Total Protein Equivalent Brix Proposed % of Calves
(g.L) levels (g/dL) levels% in each category
Excellent Greater than or Greater than or Greater than or Greater than
equal to 25.0 equal to 6.2 equal to 9.4 40%
Good 18.0 to 24.9 5.8 to 6.1 8.9 to 9.3 Approximately 30%
Fair 10.0 to 17.9 5.1 to 5.7 8.1 to 8.8 Approximately 20%
Poor Less than 10.0 Less than 5.1 Less than 8.1 Less than 10%
These certainly are challenging if you only standard has been 5.0 or higher for success.