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by Paul
on September 1, 2010 at 2:08 PM
Every one of the last ten studies published comparing Salmonella rates between cage and cage-free egg operations found higher rates in the cage facilities.  
The connection is so clear that industry trade publication World Poultry published an article on 5-20-10 entitled "Salmonella Thrives in Cage Housing,” when they conclude: “It is likely that the type of housing that layer hens are kept in influences the occurrence of infection. This appears to be in the advantage of flocks that are reared in alternative housing systems in comparison to cage systems.”
by Pamela Kan-Rice
on September 3, 2010 at 4:17 PM
Paul, I asked Michele Jay-Russell, a food safety and security specialist at the Western Institute for Food Safety and Security (WIFSS), a program of the UC Davis School of Veterinary Medicine, about your assertion. She looked up the reference:  
Jay-Russell said, “The article also goes on to say that factors other than housing may be important, such as herd and flock size, stress, age of the building, rats and mice, vaccination status and other Salmonella species.”
by Paul
on September 3, 2010 at 7:09 PM
The article quotes an economist as saying he suspects cage-free is worse for Salmonella than cage, and quotes a poultry specialist as saying cages are best. But the article doesn't present any evidence to back up the claims.  
We can't ignore that ten out of the last ten studies published on the topic found higher rates of Salmonella in cage operations than cage-free. You can see all ten studies at  
Thanks and I hope you have a great weekend.
by Pamela Kan-Rice
on September 7, 2010 at 10:04 AM
The studies have found mixed results. See,0,3139990.story  
"There's little evidence that salmonella levels are any different in commercial birds compared to birds housed at smaller farms or in backyards, Jay-Russell adds. A 1996 study published in the journal Avian Disease found higher levels of a specific type of salmonella in free-range compared to caged birds. But a 2004 study conducted by researchers at the Poultry Microbiological Safety Research Unit at the Richard B. Russell Agricultural Research Center in Athens, Ga., found no difference in salmonella levels in free-range chickens compared to conventionally raised chickens."
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