[nicky d]

I was reading through a poultry magazine and came across this new product for hens,

http://www.berylsbackyard.co.uk/

[ehs284]

What a load of ******. The idea of friendly bacteria and unfriendly ones is an anthropomorphic nonsence loved by advertisers. In the gut of warm blooded creatures, such as ourselves and hens, there are a large number of bacteria. The largest number belong to the Escherichia coli species and for that reason E.coli are used in tests for faecal contamination. These are the normal gut flora in healthy animals. There are a few VTEC E.coli which are pathogenic (eg. O517:H7) because they 'inject' a toxic into the bloodstream which destroys blood cells which in turn damages the kidneys, but these are rarely found away from infected cattle, although they cause headlines if causing a human outbreak. The simplified role of the normal gut flora E.coli is to produce vitamin E and to control other bacteria by being able to deprive the others of food and space - hence the idea of competition. A good example is Clostridium difficile. You'll see this as a hospital aquired infection. In fact about 1 in 20 adults and up to a quarter of children have this bacteria in their gut and it doesn't cause any problems. When ill and given antibiotics the E.coli are damaged/killed and without competition, the C. difficile multiplies causing diarrhoea etc. Poor hygiene then allows the other 80% to become infected. E.coli can cause infections of wounds as can many common bacteria, but trying to remove them is nonsense. You need E.coli. Of the other bacteria mentioned in that link, Salmonella has been a major problem and now is controlled by vaccination of chickens and Clostridia are very common anaerobic bacteria which can cause illness in humans if they (or their toxins) are consumed. More commonly they are the cause of gas gangrene (in wounds) or botulism in wild water birds, but shouldn't be a worry for well kept hens. HTH

[nicky d]

you should send that reply into the magazine    nickyx

[tantamount]

Whilst I don't want to make any judgement on the product, I would take issue with a couple of points made by ehs24. Friendly and unfriendly bacteria is a simplistic way of trying to help the layperson understand that there are differences in bacteria - some cause disease others don't and there is grey area of ones that can cause disease if given the correct conditions.
The most prevalent bacteria in the gut are most certainly not Escherichia coli. The numbers of E.coli in the avian gut is several orders of magnitude lower than the Clostridia, Enterococci or Lactobacillus. The bacterial flora of poultry is clearly laid out in Paul Barrow's analysis 'Microflora of the alimentary tract and avian pathogens: translocation and transmission'  pages 117-138 in Microbiology of the Avian Egg by Board and Fuller 1994.
The pathogenicity of E.coli is variable. There are strains that are relatively innocuous and there are frank pathogens such as O157. This is because their pathogenicity is dictated by their ability to produce virulence determinants such as toxins, adhesins, siderophores etc. The E.coli that are normally resident in the gut are commensal (i.e. possess few virulence determinants) but they can be displaced by pathogenic variants. The product appears to attempt to re-establish the commensal strains at the expense of any pathogenic ones that might be present.
Clostridia are very common in the gut as mentioned above. However, they do not just cause gas gangrene or botulism. Clostridium perfringens is a gut pathogen that (in susceptible birds - usually with a concomitant coccidia infection) causes necrotic enteritis - a serious, potentially fatal,  disease of poultry.
I agree that Salmonella can be controlled with vaccination but other options include the use of competitive exclusion products like Orion's Broilact or Schering Plough's Aviguard.
I hope this helps.

[joyfull]

hello tantamount and welcome, why not pop over to the welcome section and introduce your self properly. You seem to have a bit of knowledge there or is it taken from a book (not meaning to offend here but we do have people just copying items as if it was their own knowledge) ? If knowledge please could you let us know what it is you do (scientists, lab technician, vet etc) or if from a book etc please could you post a note acknowledging the author (copyright laws). Do you keep chickens? If so what breeds and how many etc. If you do please could you post some photos for us all to look at - we love photos 

[ehs284]

Hi Tantamount,
Sorry, but here we are not talking about avian species in general; only about poultry. True some species of birds do not have Escherichia sp as commensals, but pigeons and poultry do have it as a normal inhabitant of the intestine. The proportional numbers of gut flora species do change and stating a fixed proportion would be wrong (although 30% is sometimes quoted), but to state that E.coli in the gut of a hen is several orders of magnitude lower than Clostridia, Enterococci or Lactobacillus is incorrect. Lactobacillus is often given to poultry and animals as a prophylactic because it lowers the pH of the crop or gut and so inhibits the multiplication of Escherichia.It is commonly found in the crop and vagina.  Bacillus subtilis is also used as a competitive exclusion agent or replacement (?) commensal. You're quite right about Clostridium perfringens or C. colinum causing nectrotic enteritis, but the C.perfringens is usually controlled by a vaccine. Funnily enough this is a Schering-Plough product, just like Aviguard. The more common (in the environment) C. botulinum is not pathogenic It is consumption of the toxin produced outside the body which causes botulism. Bacteriophages are used in some parts of the world to control pathogens, but are generally regarded with suspicion in the UK.
The point really in connection with competitive exclusion agents is that they need careful use because they may be antagonistic to one another or existing non pathogens by changing the environment depending upon factors such as the food. Aviguard can be used in flocks because all other factors are controlled. Unless all the other factors are controlled then the benefits of giving bacteria as competitive exclusion agents is dubious and especially so for free ranging birds.

[Aunt Sally]

OK both. 

This may be a very interesting topic to both of you but it goes over the head of the majority of our members.  If you wish to carry on this debate please do it by PM.

Let me know if you want to Tantamount and I'll ensure you can send PMs.

[Ice]

You beat me to it Aunty.  Way beyond what the forum is all about and belongs in somewhere more specialised.  Though it's probably true to say that the outcome is of interest to poultry keepers.

[Aunt Sally]

I would never beat you Ice.  I abhor violence 

[Caralou]

I was finding it really interesting (but then I can be science geek at times)  Agree though, simplification would help for those of us who aren't specialists in this area 

[Aunt Sally]

They are just two microbiology geeks locking horns.

I worked in microbiology for quite a number of years before I moved to Kent so I know that's what they are doing.  It will add no information of value to the membership here

[Ice]

Glad I'm not the only science geek here.

[Aunt Sally]

And hockey geek and ....

[Aunt Sally]

.... we ban people for being geeks 

[Ice]

And hockey geek and ....

Now that's fighting talk.