| dc.description.abstract | The objective of this investigation was to evaluate the effects of administering
CpG-ODN to commercial strain chickens as a potential adjuvant to vaccination against
Salmonella, Eimeria spp., and Newcastle disease virus, or immunization to bovine
serum albumin (BSA). During Experiment 1, which evaluated the dual application of
CpG-ODN and a Newcastle disease virus vaccine, in the first of three replicate trials,
on day 28 of the experiment, animals in the Vaccine + CpG 1& 14 experimental group
were observed to have the highest levels of (p<0.05) anti-NDV IgG in serum. These
levels were elevated above levels in animals from all other experimental groups. This
suggestion for an adjuvant effect associated with CpG-ODN administration was not
supported in the remaining two trials of experiment 1.
Experiment 2 evaluated the potential for CpG-ODN to adjuvant a commercial
live oocyst coccidial vaccine when applied by an oral route to neonatal broiler
chickens. Overall, when body weight gain during challenge, development of intestinal
lesions, and anti-Eimeria IgG levels were evaluated, vaccine administration alone was
demonstrated to provide the best measure of protection among animals in all
experimental groups, including those receiving either CpG-ODN or Non CpG-ODN.
Experiment 3 investigated the simultaneous administration of CpG-ODN or
Non-CpG ODN and a commercially acquired Salmonella typhimurium vaccine to
SCWL chickens. Similar to experiments 1 and 2, antigen specific IgG responses in
serum and indices of protection against field strain Salmonella challenge were variable
and inconsistent.
Anti-BSA IgG levels were compared in broiler and SCWL chickens immunized
against BSA by a drinking water route of administration alone, or in combination with
two different concentrations of CpG-ODN or Non CpG-ODN in experiment 4. The
only observation where CpG-ODN and BSA co-administration resulted in anti-BSA
IgG levels that were elevated above BSA alone immunized chickens was measured in
broilers at day 19 post-final immunization.
Taken together, given the variable results reported in this investigation related
to the co-administration of ODN and vaccine or protein antigen, these data are largely
inconclusive for suggesting that CpG-ODN can effectively adjuvant humoral immune
responses in commercial strain chickens. | en |
