Note the dark hair on the lower neck. This
represents the thymus gland activity.
The thymus
gland represents good immune
function. Note the deep sheen/shine of the hair coat. this represents a
very active immune response. These kind of cows do not get sick nor do
their calves. If I look at a cow/bull to purchase this is the very
first thing I look for. If I cant see a large thymus whorl I am not
interested in purchasing the animal. The thymus gland gives the white
blood cells their marching orders. If the hair coat and the thymus
gland are not visible then the animal is susceptible to the stresses
and diseases that plague our industry.
In the dairies that
feed a lot of starchy
supplements the hair is short and maybe a little sheen, however the
thymus and other glands are not very often visible. The sebaceous fluid is not healthy in the grain-fed cows.