Alternatives to Antibiotics Competitive Exclusion Dik Mevius, IPPE February 2013
Principle of CE (Wikipedia) n
In ecology, the competitive exclusion principle, is a proposition which states that two species competing for the same resources cannot coexist if other ecological factors are constant. One of the two competitors will always overcome the other, leading to either the extinction of this competitor or an evolutionary or behavioural shift towards a different ecological niche. The principle has been paraphrased into the maxim "complete competitors cannot coexist".
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First described by Grinnell, J. (1904). "The Origin and Distribution of the Chest-Nut-Backed Chickadee". The Auk (American Ornithologists' Union) 21 (3): 364–3821. Gause, G.F. (1934). The struggle for existence. Baltimore, MD: Williams & Wilkins Hardin, G. (1960). The Competitive Exclusion Principle. Science 131, 1292-1297.
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www.southtexascollege.edu
http://www.nature.com/scitable/knowledge/library/the-maintenance-of-species-diversity-13240565
History of CE in poultry
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First used in poultry in 1971 to control a S. Infantis outbreak in Finland l
Rantala and Nurmi, Br. Poult. Sci., 14: 627-630. 1973
Mechanisms involved (Nurmi et al, 1992)
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(1) Competition for limiting nutrients; (2) Competition for attachment sites on the mucosa; and (3) Production of antibacterial substances, e.g. volatile fatty acids, bacteriocins.
Purpose of usage of CE in poultry
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Predominantly l
Control of colonization of enteropathogens • Salmonella, – Campylobacter – Pathogenic multi drug resistant E. coli – Clostridium infection – ESBL-producing E. coli
Types of CE-flora
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Freeze or vacuum dried intestinal flora of adult SPF animals Commercialized l Home made l
1988, Veterinary Quarterly, 10:4,249-255
CE used in Salmonella control in 1980/1990s in The Netherlands Broilers
Reproduction animals
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Spray of chickens/eggs in hatching units
Spray of adult animals after 10 days orally administered enrofloxacin “Salmonella repair”
NUTRITIONAL EFFECTS OF BROILACT® IN POULTRY PRODUCTION
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TABLE 2. Effects of the BROILACT® treatments on pH and volatile fatty acid concentrations (VFA) in the intestines of the broiler chickens at 12 d of age
Variable pH duodenum pH ileum pH ceca Ileum, mmol/g Acetic acid Propionic Butyric Isovaleric Capronic Ceca, mmol/g Acetic acid Propionic Isobutyric Butyric Isovaleric Valeric
Control
BROILACT® 1 ×
BROILACT® 5 × 5.97 7.56 5.63
SEM
Significance
0.011 0.066 0.081
NS NS NS
6.02 7.45 5.24
5.97 7.75 5.32
46.60 0.36 0.20a 0.22 0.03b
55.00 0.45 0.06ab 0.17 0.15a
31.60 0.43 tracesb 0.15 0.15a
4.000 0.018 0.033 0.013 0.021
NS (P = 0.054) NS (P = 0.075) * NS (P = 0.08) **
109.90 6.80b 0.31 14.80 0.29b 0.59b
109.90 16.20ab 0.51 13.60 0.59ab 1.27ab
118.20 17.50a 0.62 18.20 0.69a 1.57a
3.830 1.890 0.057 1.130 0.059 0.166
NS * NS (P = 0.055) NS * *
a,bMeans
within a row with no common superscript differ significantly (P < 0.05). *P < 0.05. **P < 0.01.
environment take place, the number of C. perfringens
butyric acid producers (especially clostridia), from the
Multi drug resistant E. coli
Avian Dis. 2002 Jan-Mar;46(1):198-202. Effect of a commercial competitive exclusion culture on reduction of colonization of an antibioticresistant pathogenic Escherichia coli in day-old broiler chickens. Hofacre CL, Johnson AC, Kelly BJ, Froyman R. Department of Avian Medicine, College of Veterinary Medicine, University of Georgia, Athens 30602-4875, USA. n
CE-flora applied to day-old-chickens resulted in 3 – 4 log10 reductions of E. coli O78:K80 colonization of the GI tract
Avian Dis. 2001 Jan-Mar;45(1):149-56. Reduced incidence of Clostridium perfringens-associated lesions and improved performance in broiler chickens treated with normal intestinal bacteria from adult fowl. Kaldhusdal M, Schneitz C, Hofshagen M, Skjerve E.
National Veterinary Institute, Dep, Oslo, Norway. Broilact in combination with Narasin resulted in a non-significant effect in a field trial on a farms
Effect of CE on ESBLs? Will CE flora prevent transfer of epidemic ESBL-carrying plasmids?? Is the reduction sufficient to control risks attributed to poultry?? Prerequisite: CE-flora should contain E. coli with the same plasmids on which the ESBLs are located (IncI1)
ESBL increase in young boilers (first week 0 – 100%)
Transmission in the Poultry production pyramid AmpC
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Associated by usage of ionophores?? l
“CE-effect” on GramPositive flora??
ESBL + AmpC
GPS
PS
Broilers
Summarize the effect of CE-flora
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Not an alternative to antibiotics Supports the control of enteropathogens/resistant organisms In the absence of antibiotics!! l No evidence that it results in control of bacterial infections l
How can the ‘health’ of the animals be controlled without systematic usage of antibiotics??
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The solution is not in a bottle!! Needs a holistic approach!! Not based on substances with antimicrobial activity!!
Sustainable, Healthy Food-Animal Production
Environment High Health
Gut Health
Pathogen
Animal
Sustainable, Healthy Food-Animal Production
Environment Gut Health
Pathogen
Feed quality Supplements An4bio4cs Management Zoonotechnics
Virulence Preven4on (vaccine) Diagnos4cs Epidemiology
How can gut health be measured How can we control it
Animal
Microbiome Immunity Physiology Epigene4cs Metabolism
As an alternative to antibiotics
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To balance “gut health” without antibiotics?? l
CE-flora could play a crucial role in the interaction between environmental and host related factors.
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CE-flora and antibiotics are incompatible l
In feed, drinking water administration of antibiotic AB for therapy or as growth promoter will result – in high concentrations in the GI-tract
– Residues in litter and drinking water
Residues in drinking water
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On 49% of Dutch Broiler farms (N = 87) antibiotic residues were found in drinking water while no antibiotics were administered
Residues found in 87 broiler farms
1 â&#x20AC;&#x201C; 1000 PPB
Conclusions
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CE-flora not an alternative to antibiotics l It may support ‘gut health’ in the absence of antibiotics l