الفهرس 
REVIEW OF LITERATUREOnly 14 pages are availabe for public view
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Abstract
Phytochemicals (‘phyto‐‘ from Greek ‐ phyto meaning ‘plant’) or phytoconstituents
are a large group of plant‐derived compounds responsible for protecting the plant against
microbial infections or infestations by pests (Abo et al., 1991; Liu, 2004; Nweze et al., 2004;
Doughari et al., 2009). Phytochemicals have been isolated and characterized from fruits such
as grapes and apples, vegetables such as broccoli and onion, spices such as turmeric,
beverages such as green tea and red wine, as well as many other sources (Doughari and
Obidah, 2008; Doughari et al., 2009).
Recommended intake for phytochemicals does not currently exist. Today, many
health authorities such as the American Cancer Society and the American Heart Association
recommend consuming a diet high in fruits and vegetables to ensure that an individual ingests
an adequate amount of phytochemical compounds. Hundreds of phytochemical compounds,
with several different biological functions, have been identified in plant‐based foods.
Therefore, consuming a variety of plant‐based foods helps to ensure that individuals receive
the optimum benefits from the fruits and vegetables consumed (Manach et al., 2004).
Lycopene is a carotenoid that is mostly present in vegetables and in some fruit species
as a red pigment (pineapple, orange, grapefruit, tomato, sweet pepper, strawberry).
Tomatoes and related tomato products are the major source of lycopene. The amount of
lycopene in fresh tomato fruits depends on the variety, maturity, and environmental
conditions under which the fruit matured. More than 80% of processed tomatoes are
consumed in the form of tomato juice, paste, puree, ketchup, sauce, and salsa while the
tomato skin is a rich source of lycopene(Shi and Maguer,2000; Thompson et al., 2000).
Lycopene is extraordinarily efficient in the control of degenerative diseases, it is a preventive
against cardiovascular diseases and cancer of prostate gland, digestive tract, skin, it decreases
a risk of the cancer of pancreas, and it blocks the formation of noxious cholesterol. Many
studies dealing with the importance of lycopene for human health and disease have been
published. Lycopene is a powerful antioxidant that has been shown to neutralize free radicals,
especially those derived from oxygen, this action could be beneficial to poultry because risk
free radicals are formed under stress, fast growth, high reproduction rates and intensive
metabolism conditions of poultry and lycopene could play an important role in the antioxidant
defense system. (DiMascio et al., 1989; Rao and Agarwal, 1999; Rao and Shen, 2002).
Results and Discussions
55
Allicin is a precursor of a number of secondary products formed in aged garlic and
crushed garlic preparations. Allicin possesses various biological activities among which
antibacterial, antifungal and antiparasitic effects are included (Lawson et al., 1998). In
addition to that it reduces serum cholesterol and triglyceride levels as well as atherosclerotic
plaque formation and platelet aggregation, it inhibits cancer promotion and decreases ocular
pressure (Agarwal,1996). It was also shown that garlic preparations effectively reduce serum
cholesterol and triglycerides as well as inhibit platelet aggregation and lowering of ocular
pressure (Eilat et al., 1995; Agarwal, 1996). The antioxidant properties of garlic were also
suggested by showing that organosulfur compounds from garlic inhibited the peroxidation of
lipids and possesses anti oxidant and radical scavenging activity (Prasad et al., 1996). Garlic
preparations may thus play a role in preventing cardiovascular diseases including
atherosclerosis as well as in tumor reduction. It may be also influence aging and many other
processes connected with the generation of free radicals (Ames et al., 1993). Two possible
mechanisms of allicin action were suggested. One stressed the antioxidant activity of allicin
while the other suggested that the particular structure of allicin make it a good candidate for
interaction with SH‐groups of proteins and other biological active molecules (Cavallito et al.,
1944; Wills, 1956).
This work aims to investigate the effect of vitamin E and phytobiotics (Lycopene and
allicin ) on the productive and reproductive performance, egg quality, some physiological and
blood biochemical parameters of the Gimmizah chickens.