Available online 12 June 2014
Open Access
Review article
Role of nutraceuticals in gut health and growth performance of poultry
- Open Access funded by King Saud University
- Under a Creative Commons license
Abstract
The
gut is a fundamental organ system which makes up two equally important
functions, i.e., the digestion and host defence. To elicit the
well-functioning and healthy gut, the dynamic balance of gut ecosystem
is of importance. A wide range of factors related to diets and
infectious disease agents seem to affect this balance, and subsequently
affect the health status and production performance of the chicken. With
the ban and/or reduction of the use of antibiotic growth promoters
(AGPs) in poultry production, the alternatives to AGP are needed
especially to preserve the balance of gut microbiota in chicken. This
review provides a summary of the potentials and possible mechanisms of
action of some alternatives to AGP (referred as nutraceuticals) in
improving the gut microbial ecosystem and immune system as well as
growth performance of poultry.
Keywords
- Nutraceuticals;
- Gut microbiota;
- Immune system;
- Growth;
- Chicken
1. Introduction
The
high growth rate and feed efficiency are the two main targets in
poultry production. A number of factors should be taken into
consideration for the optimum performance of birds including genetic
potential of the birds, quality of the diets, environmental condition
and disease outbreaks. Apart from these mentioned-factors, gut health
has recently been the subject of intense studies in poultry production (Rinttilä and Apajalahti, 2013).
The gut is a pivotal organ system which mediates nutrient uptake and
use by the animals. The gut is also a major site of potential exposure
to environmental pathogens (Yegani and Korver, 2008).
Hence, a well-functioning and healthy gut is the cornerstone of the
optimum performances of the birds. When the gut function and health are
impaired, digestion and absorption of nutrients are affected and thus
the health and performance of birds will be compromised.
Besides
responsible for the absorption of nutrients from the lumen, intestinal
mucosa of broiler chicken plays an important role in providing an
effective barrier between the hostile luminal content and the host
internal tissues. In this notion, intestinal mucosa is an important
determinant of gut health and performance of chicken (Rinttilä and Apajalahti, 2013).
To support the intestinal mucosal barrier functions, the dynamic
balance between the mucus layer, epithelial cells, microbiota and immune
cells in the intestine is of importance (Schenk and Mueller, 2008).
A number of factors associated with diet and infectious disease agents
have been reported to affect this dynamic balance, and subsequently
affect the health status and production performance of the chicken (Yegani and Korver, 2008).
A subtherapeutic use of antibiotics has been widely practiced in
poultry industry for decades to maintain the balance of ecosystem in the
gut as well as to improve the growth performance of chicken (Huyghebaert et al., 2011). However, this practice has been questioned, given the increasing prevalence of resistance to antibiotics in chicken (Kabir, 2009).
Hence, alternatives to antibiotics are needed in poultry industry to
maintain the gut health and promote the performance of birds.
Of
the factors that may be responsible for the gut health and performance
of chicken, commensal microbiota in the gut seem to have pivotal roles
as they may help to direct the development of gut structure and
morphology, modulate the immune responses, offer protection from luminal
pathogens as well as aid digestion and utilization of the nutrients (Rinttilä and Apajalahti, 2013). In their review, Yegani and Korver (2008)
suggested that gut microbial profile can be affected by diet, in which
the changes in dietary composition may result in the alteration of the
microbial community in the gut. In addition to that, some foods or food
ingredients have been reported to modulate the gut microbiota and immune
system which may be beneficial for the chicken, referred as
nutraceuticals (Huyghebaert et al., 2011).
The
objectives of this review are to describe the potentials and possible
mechanisms of action of some nutraceutical compounds (e.g., probiotics,
prebiotics, synbiotics, organic acids, exogenous enzymes,
polyunsaturated fatty acids [PUFAs] and phytobiotics) in improving the
gut microbial ecosystem and immune system as well as growth performance
of poultry. The applications of nutraceuticals for prevention and/or
treatment of enteric infections in poultry are also briefly summarized
in this review.
