A number of feed additives including antibiotics have been extensively used in
poultry diets for the purpose of weight gain to improve feed efficiency and growth rate.
However, use of antibiotics has restricted due to the bacterial resistance and the issue of
residues which make the chicken meat harmful for human consumption. So the medicinal
plants are gaining interest as alternative feed strategies now a day because of their low cost,
easy availability and presence of no residues. Garlic was used for the medicinal purposes and
as a health supplement by the ancient Egyptians. It is a natural feed additive and is
antimicrobial, immune stimulator, antiviral, antifungal, anti-parasitic, antithrombotic,
antioxidant, anti-cancerous, and vasodilator activities. Previous studies indicate that it has
beneficial effects on the immune system and is a best immune stimulator then the other
herbal plants and medicines.
Therefore, the present study was designed to estimate the immunomodulatory effect
of garlic to commercially available IBD vaccine in enhancing the immune system. Total
N=99 day old broiler chicks were purchased and kept in the experimental shed of CVAS
Jhang. Birds were divided into three groups A, B, C and group B and C were further divided
into three subgroups (B1, B2, B3 and C1, C2, C3). Group A was treated as control group and
was administered with commercially available IBD and ND vaccine and routine diet while
group B was administered with garlic at the rate of 4%, 5%, and 7% along with vaccine to see
the impact of different levels of garlic (Allium sativum) on the immune system and to see the
toxic effect (if any) of high dose of garlic. Group C was only administered with garlic in fee
Summary
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at the same rate as to group B. At the end of study birds were slaughtered to check the effects
of garlic administration. Positive effect of garlic has been reported by many studies. Garlic is
a medicinal herb used for the prevention and treatment of many diseases, because of having
antiviral, antibacterial and antifungal activities. Also act as a good growth promoting agent
and have beneficial effects on the immune system. Results of the study indicate that
administration of garlic powder in different doses alone and combined with commercial IBD
vaccine have good effects on the growth, blood parameters and the immune system of the
broiler birds.