Review Article
Beneficial Implementation
of Probiotics in Farm Animals and Poultry Husbandry
Ehab A. Fouad1*,
Magdy A. Kamel2 and Ashraf S. Hakim2
1Department of Zoonosis, National
Research Centre, 33 Bohouth St., Dokki,
Cairo, Postal code 12622, Egypt
2Department of Microbiology and
Immunology, National Research Centre, Dokki, Cairo,
Egypt
Corresponding author: ehabfoaud@gmail.com
Submitted:December16th,
2022
Revised:February25th,
2023
Accepted:
March1st, 2023
Published:
June 28th, 2023
DOI: https://doi.org/10.33687/ricosbiol.01.01.0016
Abstract
Probiotics have become highly realized as additives for
livestock because of their beneficial impacts on health and well-being. The
current article aims to provide knowledge about the potential probiotic
microbial strains referred to their relation to animal health. Lactic acid
bacteria are the most regularly used microorganisms as probiotics, "besides
other microbiota including certain fungi" which can be obtained from
human, animal, plant, and environment. Not all microbiota be a good probiotic
but there are main selection criteria for any potential probiotic microorganism.
Nowadays, probiotics are used on large scale as growth promoters and
productivity enhancers in both poultry and farm animals. Finally the promising
probiotic must achieve the safety status for humans or animals and lack of
antibiotic resistance genes transfer.
Keywords: Probiotics- Mechanism of Probiotic- Probiotics selection
criteria
Introduction
Probiotics
are nonpathogenic beneficial microorganisms. They have microbiological, and metabolic
effects. They are very important for the health of man and animal. Lactic acid
bacteria and bifidobacteria strains are mostly used as probiotics. In
clinical and veterinary practices, they consider as prophylaxes and are used for
therapeutic purposes. They are safe, good chance of replacing antibiotics in
animal husbandry, and viable alternative to antibiotics for increasing
performance in livestock, besides nutrient digestibility [1]. It was reported that
about 4.4 and 4.8 billion dollars in 2020 and 2021 respectively profits from
probiotic global market, expected to reach 7.3 billion dollars in 2026 at a
CAGR 8.8% in the animal feed market; farm and pets animals [2]. Therefore, probiotics
are very important not only for health and the disease in man and animal but
also, for economic purposes. Traditional applications of probiotics have been
mostly presented through the fermentation process usually directed to digestive
processes. More than 1000 years ago, old Carthusian silos and ancient evidence
from Egyptian drawings show that farmers used silage for their animals during
winter times as it was an excellent way to preserve summer crops [3].
1. What is a Probiotic?
The
term probiotic is meaning ‘for life’. It is a composite of the Latin
preposition pro (“for”) and the Greek adjective (biotic) from the noun bios
(“life”) [4] although they have sundry different meanings over the years. Probiotics
are nowadays defined as “Live microorganisms that when administered in adequate
amounts confer a health benefit on the host” [5].
2.
Classification of Probiotics:
Figure (1): classification pattern
of probiotics; [1,
6-8].
2.1.
Lactic acid bacteria (LAB):
· Genus Lactobacillus: Lactobacillus acidophilus, L.
brevis, L. bulgaricus, L. casei, L. cellobiosus,
L. curvatus, L. delbrueckii
spp. bulgaris, L. fermentum, L. gallinarum,
L. helveticus, L. johnsonii, L. lactis, L. paracasei, L. plantarum, L. reuteri,
L. rhamnosus;
· Genus: Streptococcus spp.: Streptococcus salivaris, Streptococcus thermophiles;
· Genus: Lactococcus: L. lactis cremoris;
· Genus: Leuconostoc: Lc. mesenteroides
· Genus: Pediococcus: P. pentosaceus, P. acidilactici.
2.2.
Bifidobacteria:
· Genus: Bifidobacterium: B. adolescentis,
B. animalis, B. bifidum, B. breve, B. essensis, B. infantis, B. laterosporum, B. thermophilum, B. longum.
2.3.
Propionibacteria:
· Genus: Propionibacterium: P. acidipropionici,
P. jensenii, P. freudenreichii, P. thoenii.
2.4.
Enterobacteria:
·
Genus:
Enterococcus: E. fecalis, E. faecium.
2.5.
Sporulated
bacteria:
·
Genus:
Bacillus: B. alcolophilus, B. cereus, B. clausii, B. coagulans,
B. subtilis.
2.6.
Other
bacteria:
·
Genus:
Escherichia: E. coli;
·
Genus:
Sporolactobacillus: S. inulinus.
2.7.
Yeasts:
Genus: Saccharomyces: S. cerevisae (boulardii).
3. How to select a good probiotic?
The good
probiotic has certain features; viable cells, non-toxic, non-pathogenic, a
beneficial effect on the host animal, surviving and metabolizing in the gut
environment condition at low pH and presence of bile, adherence to intestinal
cells lines, stabilization of the intestinal microflora, production of certain preparations
(i.e., bacteriocins), colonization and multiplication faster, generic
specificity of probiotics and viable for long periods under certain conditions [9].
4. Efficacy of Probiotics on farm animals:
4.1. Polygastric
Animals
The
most widely distributed animals of mammals are ruminants, which moreover about
150 wild and domestic species, while cattle, sheep, goats, and water buffaloes
are very important due to economic interest [10]. There are microorganisms in
the rumen microbiome which composed mainly of bacterial species moreover,
flagellated and ciliated protozoa, fungi, methanogenic archaea and
bacteriophages [11] and present in the rumen with the level of 1010
(bacteria), 108 (protozoa), 107 (archaea), and 103
(fungal spores) CFU / ml in rumen fluid [12].
The
fermentation process, in the ruminants and farm animals, is essential for
health and productivity. It is depended on the rumen microorganisms which are killed
or decreased due to the use of the systematic antibiotics “used as growth
promoters in animal husbandry”. Not only had the use of antibiotics affected
the rumen metabolism but also, releasing multidrug-resistant microorganisms and
antibiotic residues in animal products [13].
Over
the world; in the European Union, probiotics are widely used in animal
husbandry and livestock production. Also, China, USA, and Australia use
probiotics instead of antibiotics [14-19]. Digestive disorders and GIT
pathogens can be treated via using probiotics [20], and control of pH in the rumen
[21], enhanced animal performance, digestibility of fiber, and increased
efficiency of feed conversion [22], production of huge milk yield and improved composition
of milk and colostrum [23-25], treatment of mastitis [26, 27] and mitigation of
methane [28, 29] stimulation of the immune system [30].
The
pre-ruminant life of calves, lambs, and kids goat is critical life as they are more
susceptible to enteric diseases so the administration of probiotics orally,
directly, or in the feed is very essential to save them [31, 32]. Lactobacillus, Bifidobacterium, Streptococcus, Enterococcus species,
Escherichia coli, Bacillus, fibrolytic Prevotella species and lactic acid bacteria, (Propionibacterium
and Megasphaera elsdenii)
had been reported to use them as probiotics [33, 34]. In buffaloes and
reindeers, cellulolytic Ruminococcus species
are used [35, 36] Saccharomyces cerevisiae and Aspergillus oryzae
are used as yeasts and fungi probiotics [37].
Table (1): some applications of
probiotics in ruminants.
|
Effects |
Probiotics |
References |
|
Control of
disease of Feedlot cattle, beef steer, Lithuanian Black-and-White, calve |
Propionibacterium
spp., Enterococcus faecium, Lactobacillus acidophilus |
[38] |
|
Inhibition of Staphylococcus aureus invasion in bovine
mammary epithelial cells |
Lactobacillus casei CIRM-BIA 667, Lactobacillus casei BL23, and Lactobacillus
casei CIRM-BIA 1542 |
[39] |
|
Nutrition digestion of Calves(Holstein–Friesians, Friesian–Jersey) |
Bacillus amyloliquefaciens |
[40] |
|
Yield
improvement of newly born ruminants |
Bacillus
licheniformis, Bacillus
subtilis, Prevotella bryantii |
[41] |
|
Increase in growth performance, improving weight gain, feed conversion
efficiency in weaning calves |
Bifidobacterium, Lactobacillus, and Enterococcus |
[42] |
In
Egypt, some trials were performed to explore the beneficial effects of
probiotics additives on ruminant performance, productivity and health; Hassan
et al., (2020) [43] investigated the mixing of two different forms (powder or
liquid) of Ruminococcus flavefaciens
with concentrate feed that presented to group of Barki
lambs for75 days. They mentioned that the addition of examined probiotics resulted
in a significant increase in nearly all of the dry matter digestibility
coefficients, average daily gain and nutrient digestibility compared to the
control group. Another study probed the influence of Saccharomyces cerevisiae dietary
yeast supplement fed by examined primiparous and multiparous Egyptian buffaloes
in early to mid-lactation. The study’s results revealed increase in milk
production in early lactation and a more persistent milk production during
mid-lactation. Feed conversion and energy and nitrogen conversion efficiency
increased with the use of yeast supplementation [44].
4.2. Monogastric Animals
Pigs,
poultry and horses are monogastric which have simple stomach. The bacteria, archaea,
methanomicrobia, and thermococci
have been identified as microbiota of pigs [45, 46]. There are 13 phyla of
bacteria were estimated in the poultry GIT with firmicutes, bacteroidetes,
and proteobacteria being the more 900 in chicken and in 500 turkey. Lactobacillus,
Ruminococcus, Bacteroides,
Clostridium, methanogenic archaea and fungi are most probiotics in chicken
and turkeys [47, 48]. The GIT of horses is improved by the presence of
beneficial bacteria, protozoa, fungi, and archaea [49, 50].
In monogastric animals, the most
probiotics are used Lactobacillus, Enterococcus, Pediococcus, Bacillus (bacteria) and Saccharomyces
boulardii and S. cerevisiae (yeasts) that
targeting the cecum and the colon. The probiotics in monogastric animals are
beneficial in increasing body weight, reducing diarrhea risk, improving feed
efficiency, and digestibility of diet [51]. In swine, there was increased diet
intake and weight performance in the period of pregnancy and lactation [52,
53]. Probiotics have been provided supportive care to piglets during their
suckling and weaning life, Kim et al. (2014b) [54] illustrated that
probiotics are more effective than antibiotics on the growth performance of
pigs. Reduction of Salmonella infection [55],
and protect against
other enteric pathogens in post weaning piglets
[56].
On the other hand, the concentration of ammonia in the excreta of poultry can be
reduced by using probiotics like Enterococcus faecium and Bacillus
subtilis [8], reduction of Salmonella and Campylobacter
colonization [55, 57, 58], prevention or treatment E. coli infection in
broilers [59]
Regarding poultry industry in Egypt,
studies have recently directed to the impact of probiotics in poultry and
poultry meat production; it was found that probiotic cell-free supernatants of
four probiotic strains, Lactobacillus rhamnosus,
Lactobacillus fermentum, Pediococcus
acidilactici and Lactobacillus delbrueckii subsp. lactis could
significantly inhibit the growth of Clostridium perfringens in poultry
meat during storage as well as their antioxidant effect [60].
5. Antibiotic
resistance associated with probiotics:
The genes transformation is one of the serious risks
combined with probiotics; they have antibiotic resistance genes that may be
transferred to certain pathogenic microorganisms, leading to emergence of antibiotic
resistance microorganisms [61]. Therefore, it is very important criteria should
be considered at choosing of probiotics;
Lactobacillus, Bacillus and Enterococcus are of greater
risks, as they carry transferable genes, while Bifidobacteria are
considered less risky as these bacteria are non-transferable [63].
However,
even the antibiotic resistance genes present, the probiotic strains may not be
dangerous if these genes are intrinsic; in chromosomes and not transferable.
Nevertheless, precautions should be taken in used probiotics to prevent
antibiotic resistance genes transfer [63].
6. Probiotics action mechanisms:
Major action mechanisms of probiotic include competitive exclusion of
pathogenic microorganisms, improvement of the epithelial barrier of GIT, increased mucosal adhesion of intestine,
and inhibition of pathogen adhesion, releasing of anti-microorganism molecules,
and immune system modulation as shown in figure (2) and table (2) [64, 65].
Fig. (2): probiotics action mechanisms.
6.1. Competitive exclusion:
The exact mechanism of action of probiotics associated
with "competitive exclusion" or "bacterial antagonism"
which refers to the physical colonization blocking of pathogen and it depends
on microbe-to-microbe interaction by competition for available epithelial
adhesion sites and nutrients figure (3) [10].
Primary and secondary metabolites;
organic acid, volatile fatty acid (VFA), and lactic acid lower the gut pH that
is detrimental to the survival of pathogenic bacteria such as Salmonella and
E. coli [66].
Fig. (3): competition between probiotics and pathogenic bacteria for
binding sites on the intestinal epithelium.
6.2. The epithelial barrier:
There
is permanent contact between intestinal epithelium cells besides their contents
and the dynamic, variable enteric bacteria. The major defense mechanism which
protects the host from the microorganisms is the intestinal barrier and its
integrity [67]. The production of mucous, antimicrobial molecules, IgA secretion,
and the adhesion complex of the epithelial junction are defense mechanisms for
the epithelial barrier [68].
6.3. Intestinal mucosa adhesion:
The intestinal mucosa adhesion plays an important role
for preventing pathogen colonization and pathogens antagonism. It is considered
one of the most selection criteria of proper probiotics. Lactic acid bacteria
(LABs) display different surface determinants that involved in interaction with
intestinal epithelial cells (IECs) and mucous membrane. Mucin is a glycoprotein
that secreted from IECs, and represented as the main component of mucous. It
contains immunoglobulins, free proteins, salts, lipids that prevent pathogenic
bacteria adhesion [69].
Table (2): summary of different
mechanism of action of probiotics in the GIT [70].
|
Target |
Mode of Action |
|
1. Promote epithelial cell homeostasis |
·
Enhance barrier function ·
Promote cytoprotective responses ·
Improve cell survival and increase mucin production. |
|
2. Neuromodulatory effects |
·
Induce receptors on epithelial cells ·
Reduce visceral hypersensitivity and stress response |
|
3. Block effects of pathogenic bacteria |
·
Reduce pathogen binding ·
Decrease luminal pH ·
Produce antibacterial bacteriocins |
|
4. Nutritional benefits |
·
Assist in the breakdown of un-digestible foods to produce usable
nutrients |
6.4. Production of antimicrobial substances:
Probiotics
can produce various molecules that inhibit pathogenic bacteria such as hydrogen
peroxide, bacteriocins and organic acids [71, 72]. There are three different
types of protective cultures; antagonistic bacteriocinogenic
protective cultures acting by releasing one or more bacteriocins or
bacteriocin-like substances, figure (4), non-bacteriocinogenic
protective cultures table (3) and the last one is protective cultures producing
antifungal molecules figure (5) [10, 73- 76].
Figure (4): different
bacteriocin classes.
Table (3): Non-bacteriocin
antimicrobial compounds (Gioia and Biavati 2018).
|
Non- bacteriocin antimicrobial |
Substances |
Mode of action |
Target |
|
Organic acids |
Lactic acid |
Decrease the pH |
Broad spectrum against non-acidophilic microorganisms |
|
Acetic acid |
Undissociated hydrophobic form |
||
|
Propionic acid (in traces amounts) |
Disruption of the cytoplasmic membrane and interference with membrane
potential |
||
|
Carboxylic acids |
Reduction in intracellular pH |
||
|
Cinnamic acid derivatives |
|||
|
d-glucuronic acid |
|||
|
Salicylic acid |
|||
|
Benzoic acid |
|||
|
Hydroxybenzoic acids |
|||
|
CO2 |
Heterofermentative LAB |
Creates an anaerobic environment |
Aerobic bacteria |
|
Diacetyl |
Produced during citrate fermentation by some strains |
Gram-negative bacteria are more sensitive than Gram-positive bacteria |
|
|
Hydrogen peroxide |
Produced by flavoprotein oxidases in presence of oxygen |
Oxidative damage of proteins Increase membrane permeability |
Antimicrobial |
|
Fatty acids |
Long-chain hydroxylated fatty acids (C8–C12) |
Partition of the lipid bilayers of fungal membranes resulting in loss of membrane integrity |
Antibacterial and antifungal activity against a broad spectrum of yeasts and molds |
Figure (5): antifungal
peptides produced by different probiotic strains.
Conclusion and Future Prospects
Usage
of probiotics leads to many health and production benefits in farm animals and poultry.
Definitely, they will render as the best substitutional option for antibiotics
in animal husbandry for obtaining of safe meat, milk and egg production. Many feedbacks
of researchers deserve extra benefit of probiotic usage, and directed to find
the optimal dose and proper strain of probiotic microorganism for certain
required action. Refinement in their form and delivery methods will also help
in fulfilling maximum potential of probiotics. Further area of benefit can also
be explored which can be achieved via their prospect use with more clinical
trials and promising research data. Moreover, better understanding of their
mechanisms of action will help in profiting extra advantages. Although
significant amount of work is available declaring positive impact of using
probiotics in veterinary field, still more research is required to come out
with some standard protocol for their applications.
References