Stocking density impacts the kind of microbes discovered on layer hens raised in a unfastened vary atmosphere, despite the fact that no longer all the time in the way in which anticipated, published analysis revealed within the Magazine of Implemented Poultry Analysis.
“In line with a prior learn about, we’ve noticed how Salmonella switch may be very depending on stocking density. It’s actually essential to have an concept, given a specific amount of house and the birds within the house, of what’s the risk of seeing both microbes or pathogens,” defined Javier Garcia, analysis affiliate within the Egg and Poultry Manufacturing Protection Analysis Unit, U.S. Division of Agriculture (USDA) Agricultural Analysis Provider (ARS).
The analysis staff integrated scientists from the USDA and North Carolina State College.
Maximum U.S. egg layers are nonetheless housed in typical techniques, however choice housing techniques, corresponding to free-range, have grown in reputation lately because of regulations corresponding to Proposition 12, drive from animal rights teams and cage-free commitments in retail and foodservice.
In spite of the perceived animal welfare advantages of those housing techniques via customers, there can pose greater meals protection considerations.
Microbial variations
The learn about when compared the microbial load of free-range Hy-line Brown layer hens housed in both low stocking density (4.02 m2/chook) or excessive stocking density (2.01 m2/chook) each seven to 9 weeks.
The consequences confirmed the next presence of cardio micro organism within the birds housed at a excessive stocking density at week 20. The cardio micro organism integrated Enterobacteriaceae, a gaggle of micro organism that come with Escherchia coli (E. coli) and Enterobacter.
On the other hand, via the top of the learn about length, the numbers turn flopped, with the nestbox swaps from low-density flocks exhibiting extra cardio micro organism than their high-density opposite numbers.
“Usually, upper density equals upper microbial rely. On this case, we did see the ones upper microbial rely, however they weren’t as excessive as we anticipated. We anticipated it to be a lot, a lot upper than the low density and so they’re very similar, in order that used to be very sudden,” stated Garcia.
The egg samples within the high-density flocks nonetheless had the next presence of Enterobacteriaceae.
There have been no variations within the incidence of Listeria or Salmonella.
“It is a learn about having a look into dear housing techniques and every so often it may not be that simple to attract a conclusion or a very simple conclusion,” Garcia stated.
“There’s such a lot of elements that cross into those other housing techniques so far as stranger birds, atmosphere, the construction itself, the place the birds are housed, and many others. This learn about gave us a snapshot of a unmarried flock.”