Objective—To evaluate the effect of long-term treatment
with tetracycline and niacinamide on antibody
production in dogs by measuring postvaccinal serum
concentrations of antibodies against canine parvovirus
and canine distemper virus.
Animals—10 dogs receiving long-term treatment
with tetracycline and niacinamide (treatment group)
and 10 healthy dogs (control group).
Procedure—The treatment group included 9 dogs
with discoid lupus erythematosus and 1 dog with
pemphigus foliaceus on long-term treatment (> 12
months) with tetracycline and niacinamide. The control
group included 10 healthy dogs with no clinical
signs of disease and no administered medications for
the past 3 months. Blood samples were obtained
from all dogs by jugular venipuncture. Serum antibody
titers against canine parvovirus and canine distemper
virus antigens were measured, using hemaglutination
inhibition and serum neutralization, respectively, and
compared between groups.
Results—A significant difference in antibody titers
between treatment- and control-group dogs was not
found. All dogs had protective antibody titers against
canine distemper virus, and 8 of 10 dogs from each
group had protective titers against canine parvovirus
Conclusion and Clinical Relevance—These results
provide evidence that long-term treatment with tetracycline
and niacinamide does not interfere with routine
vaccinations and thus does not seem to influence
antibody production in dogs. (Am J Vet Res 2002;
Objective—To examine cross-reactivity of aeroallergens
in Colorado and surrounding states by evaluating
concurrent positive reactions of related and nonrelated
allergens of intradermal tests in dogs.
Sample Population—Intradermal test results of 268
Procedure—A retrospective evaluation of skin test
results for 268 dogs was performed. Pairs of closely
related and nonrelated allergens were evaluated.
Group 1 consisted of closely related allergens with
demonstrated antibody cross-reactivity in humans. In
group 2, allergens of the same plant group (ie, trees,
grasses, or weeds) that were not closely related were
paired. In group 3, allergen pairs were of different
plant groups. Plant allergens were paired with dust
mite allergens, animal dander, or mold spores in
group 4. In the last group, allergens not derived from
plants were paired. Data were evaluated twice by use
of a different definition of a positive reaction.
Significance of the difference between group means
of log odds ratios was estimated by use of a bootstrap
percentile confidence interval.
Results—Significant differences in the number of
concurrent positive reactions were not found
between related versus nonrelated grass, weed, or
tree allergens. Significant differences in the number
of concurrent positive reactions were found between
plant allergens of different groups (ie, grasses,
weeds, and trees) and plant allergens of the same
groups, related or nonrelated , as well as between
plant-derived and nonplant-derived allergens. Many
dogs reacting to a specific allergen did not react to a
closely related allergen at the same time.
Conclusion and Clinical Relevance—These results provide evidence against
clinically relevant cross-reactivity and suggest that
allergen-specific immunotherapy should be formulated
on the basis of single allergen test results.
(Am J Vet Res 2002;63:874–879)