Summary
The
authors evaluated the holistic efficacy of nine specific nutrient
synergy (NS) against avian influenza virus (AIV) strain Lebanon 1
(H9N2). The study included two segments; the first was designed
to determine the minimum dose among four doses (1X, 2X, 3X and 4X
in which X = 24.4 mg/ml/bird) of NS, administered
intraoesophageally, once per day between 7 and 14 days
of age, resulting in an improvement of chicken performance without
any toxic side-effects; the second aimed at reducing pathological
effects and inducing immunomodulation by the determined safe dose
of NS in chickens exposed to AIV. The first segment showed that
the daily oral administration of the NS to birds between 7 to
14 days of age at the 2X dose-level (320 mg/kg body weight
or 48.8 mg/ml/bird) resulted in a consistent and significant
improvement in the feed conversion (P<0.05) at 10 and 14 days
of age, associated with a significant (P<0.05) increase in the
liver weight index. In addition, the administration of NS at 2X
level resulted in complete absence of toxicity signs (swollen infraorbital
sinuses, ocular exudate, nasal discharge, thick oral saliva, diarrhoea,
lameness and huddling) and complete absence of toxicity lesions
(airsacculitis, hydropericardium signs, pericarditis, perihepatitis,
splenomegaly and tracheitis). The four groups of birds that received
levels 1X to 4X levels had significantly higher frequency of birds
with gaseous caeca compared to the control group deprived of NS
(P<0.05), a sign of higher fermentation activity in this organ.
Data from the second segment of this research showed that the daily
administration of NS at a level of 48.8 mg/ml/bird, between
7 to 14 days of age, to H9N2-challenged birds reduced
specific pathological effects at 14 days of age namely: absence
of rales at 3 days post H9N2 challenge and gross lesions (absence
of tracheitis and enteritis at 7 days post challenge). Such
reductions in signs and gross lesions were associated with a 63.4%
reduction in immune responses to the hemagglutinin protein of the
AIV, an indication that NS has a reducing effect on the viral infectivity
in chickens.
Keywords
Avian
influenza, Chickens, Immunomodulation, Nutrient synergy, Viruses.
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