Use of antibiotics as growth promoters is an age old process but due to many factors thrust for the search of alternative to antibiotics is growing, 'phytogenic feed additives' are one of the possible domains which could address the issue if they could be properly explored.
3. ā¢ Antibiotics in poultry feed, in general are used
regularly for increasing efficiency and growth
rate than to combat specific diseases in the
recent times.
4. Constraints of antibiotic growth
promoters
ā¢ Antibiotic resistance
ā¢ Residual levels in chicken meat and eggs
ā¢ Consumer awareness
ā¢ Legislations against the use AGPāS.
(Europeon union-2006)
8. Phytogenic feed additives
ā¢ Phytogenics or phytobiotics are a group of
natural growth promoters or non-antibiotic
growth promoters, derived from herbs, spices
or other plants.
ā¢ They vary widely with respect to their origin,
processing and composition.
ā¢ Phytobiotics are approved in chicken feed in
EU & USA( Hooge, 2004).
10. Phytobiotics classification
ā¢ Herbs: product from flowering, non-woody
and non persistent plants,
ā¢ Botanicals: entire or processed parts of a
plant, e.g. root, leaves, bark,
ā¢ Essential oils: hydro distilled extracts of
volatile plant compounds,
ā¢ Oleoresins: extracts based on non-aqueous
solvents.
11.
12. Essential oils:
ā¢ A mixture of secondary plant metabolites
which are fragrant and liquid volatile
compounds.
13. Distributi
on
ā¢ Plants contain about 0.01 ā 2% EOs
ļ¼ Leaves ā Eucalyptus,
ļ¼ Bark - Cinnamon,
ļ¼ Flower- Oregano,
ļ¼ Seeds ā pepper,
ļ¼ Bulbs - garlic.
ļ¼ Roots - ginger,
ļ¼ Fruit peels - lemon, orange.
14. Oleoresins:
ā¢ Oleoresins are semi-solid extracts composed
of a resin in solution in an essential and/or
fatty oil, obtained by evaporation of the
solvents.
ā¢ Naturally occurring oleoresins are also known
as balsams
15.
16. Functions of phytogenic feed
additives
ā¢ Stimulate secretion of digestive enzymes,
ā¢ Anti-bacterial activity,
ā¢ Anti-viral activity,
ā¢ Enhancement of immune system of the bird,
ā¢ Anti inflammatory role,
ā¢ Anti oxidant role,
ā¢ Coccidiostatic
ā¢ Anti-helementhic activity &
ā¢ Reduction of ammonia emission from poultry
barns
17.
18. Mode of action of phytogenic
feed additives
ā¢ Effect on gut morphology:
ā¢ On one side PFA irritate intestinal tissues
which have positively influenced the
secretory activity of trypsin and amylase.
(Lee et al.,2003)
ā¢ On the other side they change the microbial
population to a more favorable composition.
19.
20. Anti microbial activity
Adhere to the cell wall,
forming a crack and causing
the cell contents spill to the
medium, eventually killing
the microorganisms
phytochemicals, can block
these interactions onto the
mucosal layer of the
intestine.
Lectinācarbohydrate
receptor interactions
Direct microbicide
effect
Blocking bacterial
adhesion to gut
23. Anti oxidative effects
Anti-oxidative activities of PFA are due to
ļ¼phenolic terpenes,
ļ¼lipids protection from oxidation,
ļ¼Activation of antioxidant enzymes like super
oxide dismutase, catalase, glutathione
peroxidase and glutathione reductase.
(Cuppett and Hall, 1998)
ā¢ The use of PFA as an antioxidant is not only
important for the poultry health, but also for the
oxidative stability of their products (meat)
25. Immunostimulatory effects
ā¢ The gutāassociated lymphoid tissue (GALT) plays a
key role in digestive immunity in farm animals.
ā¢ Compounds, such as oligosaccharides from
chicory, can exert beneficial effects on gut health
by enhancing local digestive immunity through
GALT responses.
ā¢ Other substances, such as mushroom
polysaccharides or allicin from garlic, may be used
as general immune enhancers because they
activate both innate and adaptive immunity.
26. Reduction of ammonia
emission
ā¢ This is due to improved nutrient utilization
through better performance.
ā¢ Addition of PFA known to decrease the wet
litter problems.
28. Supplementation levels:
ā¢ Dried products and plant extracts-
0.1 and 40 g/kg
ā¢ essential oils and single plant ingredients (e.g.,
thymol, carvacrol) - 0.02-1.0 g/kg
(Windisch et al., 2009.)
ā¢ Supplementation of extracts or essential oils
to drinking water is even lower due to the
higher water than feed intake
29. Factors may affect the
effectiveness of PFA
ļ¼plant parts and their physical properties
ļ¼source,
ļ¼harvest time and
ļ¼compatibility with the other ingredients in
feed
(Wang et al 1998)
37. Possible complications of using
PFA
ā¢ Some PFA contain irritating ingredients which may
be harmful to birds,
ā¢ Undesired residues may not be excluded in a
natural product,
ā¢ Some, concerns are reported for capsaicin (cancer
causing), cyanide containing ingredients, carvacrol
(in oregano).
ā¢ High inclusion levels of oregano may affect the
minimum inhibitory concentration (MIC) for
antibiotics (Mountzouris et al., 2009).
38. Conclusion:
ā¢ There is no doubt that a number of PFA are
capable of modifying the gut microflora
substantially, which in turn, can bring about a
cascade of changes in the animalās responses
to nutrients, disease challenge and the
environment.
ā¢ However, inconsistent effects have been
observed in terms of growth performance.
39. Contdā¦.
ā¢ The question that remains unanswered is
what type of extracts can be recommended
and under what circumstances they can be
used.
ā¢ So further research is needed to answer these
questions and also efforts are needed to verify
the results in birds reared in practical
conditions to explore the beneficial effects.
40.
41. References:
ā¢ J.K. Vidanarachchi1, L.L. Mikkelsen1, I. Sims2, P.A. Iji1
and M. Choct3-2012 Phytobiotics: alternatives to
antibiotic growth promoters in monogastric animal
feeds.
ā¢ Mohamed Nabil Alloui1, Amir Agabou2 and Nadir
Alloui3 2014 Application of herbs and phytogenic feed
additives in poultry production
ā¢ M.A. Grashorn1 2010 Use of phytobiotics in broiler
nutrition an alternative to infeed antibiotics
ā¢ S.R. Hashemi and H. Davoodi-2008 Phytogenics as
New Class of Feed Additive in Poultry Industry