Quality colostrum, and
soon, is the best defense
for momma’s wobbly calf
STORY AND PHOTOS BY
HEATHER SMITH THOMAS
ewborn calves have an
immature immune system.
They have very little
the diseases they will
soon encounter. Mother
N t h th t N
Nature has that loophole covered, however,
by providing temporary protection
via momma’s first milk (colostrum),
which contains all the antibodies her
own immune system has produced.
This “passive immunity” may last several
weeks — even up to three months
and can protect the calf until its
body can build its own defenses.
When we talk about colostrum
quality, we’re referring to the level of
antibodies (the large y-shaped protein
molecules called immunoglobulins)
that counteract pathogens that cause
disease. When the calf is firstborn, his
intestinal lining is “open” and porous
enough to absorb these large molecules
directly through it and into
its bloodstream and lymph system.
Gut closure begins soon after birth,
(to prevent absorption of other large
molecules, like certain pathogens),
so the calf must receive an adequate
amount of colostrum within the first
few hours of life.
Some of the antibodies in colostrum
are absorbed through the intestinal
wall, while others can remain
in the gut and help combat ingested
pathogens. Even if gut closure has
occurred, some of the antibodies in
the remaining colostrum the cow provides
(until it is completely replaced
by regular milk) can provide local
protection in the calf’s gut — against
certain scour-causing pathogens, for
instance. To make sure every calf gets
to a healthy start in life, he must ingest
a large amount of high-quality colostrum
within the first 2 to 3 hours, if possible.
A cow’s colostrum quality is highest at the time of her calf’s birth. As soon
as he nurses, however, and as time passes, the quality of the colostrum
decreases, since it is being diluted with the production of regular milk.
cow’’s colostrum is highest the time calf’s As soon off to
36 I WORKING RANCH I NOVEMBER / DECEMBER 2020