While in the womb the unborn relies on the immune system of the mother. When it is born it has to fend for itself. This means its immune system has to be awakened, stimulated, balanced, and fortified immediately. That is where colostrum comes in. The first colostrum is rich in immune factors. The earlier colostrum is collected the richer it is. Colostrum transitions to plain milk hour by hour post calving, with the concentration of immune factors and other vital components decreasing dramatically around the four to six hour time frame. Goettsche Labs is collected within four hours post calving after the calves have their fill. Most colostrum on the market is harvested within a 16 to 24 hour time frame and cannot be expected to provide immunity benefits and other benefits that Goettsche Labs colostrum does. The graph below shows how colostrum transitions to milk hour by hour after calving.
Dairy Science Fundamentals
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