12-16-2015, 09:57 PM
Join Date: Sep 2014
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Nothing jumped out at me in the article you posted, so I looked for other sources on the issue. I found a study that shows that that there is no conclusive link between the two. This doesn't mean that it doesn't happen, only that the Purdue study was not very conclusive. Neither is the one I will post.
Source: Lack of Association between Repeated Vaccination and Thyroiditis in Laboratory Beagles - Scott-Moncrieff - 2008 - Journal of Veterinary Internal Medicine - Wiley Online Library
I've bolded a few parts I felt were important.
Thyroglobulin is believed to be an important autoantigen |
in the pathogenesis of thyroid disease in dogs
and humans. Experimental autoimmune thyroiditis can
be induced in susceptible mice by parenteral injection of
murine, bovine, or human thyroglobulin.16,17 Whether
anti-thyroglobulin antibodies are directly involved in the
pathogenesis of spontaneous thyroiditis is still disputed.18
Although it is believed that thyroiditis is mediated
predominantly by T cells, there is some evidence that
anti-thyroglobulin antibodies play a direct role in
initiation of autoimmune thyroiditis. Thyroiditis has
been induced by injection of canine serum containing
anti-thyroglobulin antibodies directly into the thyroid
gland of dogs.19 It is possible that the anti-thyroglobulin
antibodies detected in the dogs in this study differ from
true pathogenic autoantibodies. Anti-thyroglobulin
antibodies frequently are found in healthy humans,
and these antibodies differ in their epitopic specificity
from those found in humans with autoimmune thyroid
disease.18 The epitopic specificity of the antibodies
detected in this study was not determined.
In this study, the highest rate of thyroiditis (3/5 dogs)
was observed in the unvaccinated group of dogs. Because
of the unexpectedly high rate of spontaneous thyroiditis in
the control group, the power of this study to test for
a positive association between vaccination and thyroiditis
was low. The chance of detecting a 100% rate of thyroiditis
in the vaccinated dogs was 80%, and anything less than
100% would likely not be detected. However it should be
noted that the rate of thyroiditis in the vaccine groups
in this study was actually lower than that of the
control group. OD for canine anti-thyroglobulin antibody
activity also was not different between vaccine groups at
the time of postmortem examination. In addition, both of
the dogs with evidence of thyroid dysfunction were in
groups that did not receive the rabies vaccine. Thyroid
dysfunction in these 2 dogs was likely a consequence of
spontaneous thyroiditis. Results of this study do not yield
any evidence to support a causal relationship between
vaccination and thyroiditis.
The presence of spontaneous thyroiditis in the dogs in
this study is not surprising considering that thyroiditis is
known to be hereditary in the beagle. The use of beagles
was an intentional feature of the study design to
maximize our chance of detecting an effect of vaccination.
This was also the reason why vaccination with the
multivalent vaccine was performed every 6 months, as
is done in some kennel settings, rather than the more
typical yearly frequency. The higher than expected rate
of thyroiditis in the control group did have the
unexpected effect of decreasing the power of the study.
Because the pathogenesis of thyroiditis in beagles might
be different from that in other breeds, the results of this
study cannot necessarily be extrapolated to other breeds.
This experimental study yielded no evidence to
suggest that routine immunization causes thyroiditis in
dogs or is responsible for the high prevalence of thyroid
disease in some dog breeds
So, basically, neither study was conclusive.
Last edited by Aurora; 12-16-2015 at 09:59 PM.