Similar with the findings of microbiologic studies on
determining the etiology of caseous lymphadenitis in
sheep
11, in this study C. pseudotuberculosis. and S.
aureus are isolated from abscess contents of sheep with
caseous lymphadenitis.
On the other hand, it is determined that serum
biochemical values both in sheep with caseous
lymphadenitis and healthy sheep are between ranges
that are normal for sheep; it is also determined that the
difference between control and diseased groups in terms
of glucose, cholesterol, creatine, lactate de hydrogenase,
phosphor and albumin values are statistically not
significant. Although measured serum calcium levels are
in normal ranges in both groups12, the level of serum
calcium in sheep with caseous lymphadenitis is
significantly lower than healthy sheep; based on this
data, it is thought that low serum level of 25(OH) vitamin
D, which is one of the factors that regulate calcium
metabolism, is related with this lowness.
It is determined in the study that hematological
values in diseased and control groups are between the
ranges which are accepted to be normal for sheep13;
in addition to this, it is determined that there was a
statistically significant decrease in lymphocyte and
increase in neutrophile ratio of sheep with caseous
lymphadenitis when compared to control group
(P<0.001). It is interpreted that the decrease in
lymphocyte number in diseased group can be related to
the lysis in lymph nodules in which abscess is formed,
and increase in neutrophile number can be related to
bacterial infection.
Vitamin D receptors are identified in all of the immune
system cells, primarily the ones that present especially
antigen such as T and B lymphocytes, macrophages and
dentritic cells1. In case of vitamin D deficiency,
oscillation of pro inflammatory cytokine increases
according to a more Th1 answer. In this case, leucocyte
chimiotaxy is influenced, immune answer is destroyed
and infection tendency increases1. It is also known
that monocytes and macrophages have key roles in
activating natural immunity against invasive features of
infection agents1,4. Consistent with the results of the
studies in the literature, it is determined in this study that,
there is not a statistically significant difference between
monocyte number of sheep with caseous lymphadenitis
and healthy group; but, on the other hand there is a
significant difference between healthy group and
diseased group in terms of 25(OH) vitamin D levels.
These findings show that, for the activation of
monocytes, 25(OH) vitamin D level should be sufficient.
This result can be interpreted as; 25(OH) vitamin may
have a significant role in preventing infections.
Through cell cultures made of mouse epidermis cells,
it has been shown by the researchers14 that, vitamin D
affect to differentiation and proliferation of keratinocytes.
Studies show that vitamin D analogs activate genes that
control oscillation of peptides that have antimicrobial
effects on skin and they have significant role in
continuation of healthy structure of skin and they
decrease sun damage15. Information reported in these
studies show that when pathogenesis of caseous
lymphadenitis, which is known to be formed with the
formation of abscesses that have typical lamellation in
lymph nodules as a result of the transmission of agents,
which enter body from portantre in damaged skin, to
local lymph nodules, is combined with the findings of this
study, vitamin D’s significant becomes clearer.
It is determined that sheep with caseous
lymphadenitis has significantly lower 25(OH) vitamin D
level when compared to control group (P<0.001). As a
result, it is determined that low serum 25(OH) vitamin D
level in sheep with caseous lymphadenitis may
negatively affect protecting animals from chronic
infections.