Page 741 - Veterinary Immunology, 10th Edition

is likely that in susceptible foals, a combination of multiple
VetBooks.ir immune defects permits this otherwise innocuous organism to

cause disease.

Berghaus LJ, Giguère S, Sturgill TL: Effect of age and macrophage lineage on intracellular
survival and cytokine induction after infection with Rhodococcus equi, Vet Immunol
Immunopathol, 160:41-50, 2014.

During the first 3 months of life, puppies have a higher
lymphocyte count than adult dogs. Much of the difference is due to
+
+
CD21 B cells. The proportion of puppy CD8 T cells is low at birth
but gradually climbs to reach adult levels. A similar gradual
increase in lymphocyte numbers is seen in newborn kittens. Thymic

involution begins at around 6 months of age in both dogs and cats.
Unless additional immunological assistance is provided,
however, organisms that present little threat to an adult may kill

newborn mammals. This immunological assistance is provided by
antibodies transferred from the mother to her offspring through
colostrum. Maternal lymphocytes may also be transferred to the
fetus through the placenta or to newborn mammals through
colostrum.

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