Our Research

There is an ever increasing interest in raising backyard chickens.  Backyard chicken farmers must be ever increasingly aware of their own flock and food safety.

Sixteen scientific studies published in the last five years compared Salmonella contamination between caged and cage-free operations found that those confining hens in cages had higher rates of Salmonella poisoning.  Commercial flocks had a 25% contamination rate, while organic flocks had a 5% rate.

Backyard chicken farmers are less likely to be contaminated with Salmonella.   However, when a chicken does have Salmonella there are no outward signs to detect.  So the only way a backyard chicken farmer can protect themselves is through how they handle their eggs.

Salmonella can infect the ovaries of hens. Eggs from infected birds can be laid with the bacteria prepackaged inside. One out of every 20,000 chicken eggs contains a small amount of Salmonella that is deposited into the sac by the hen.  Chickens get doses of salmonella bacteria (of which there are 2,300 kinds) from their environment, which is easily contaminated by rodents, birds and flies. Those few contaminated eggs that come out of a hen usually contain a very low levels of bacteria - totaling between two and five microorganisms. It takes a level of at least 100 bacteria to make a person sick. Salmonella doubles every 20 minutes under ideal conditions.  If an egg sits there for an hour, two microorganisms could become 32. At two hours, there would be 1,000 organisms. At eight hours, it would be in the range of millions - in one egg.
But even if chickens remain salmonella-free, their eggs can become contaminated from the outside in. Every egg has about 9,000 pores that salmonella can essentially climb in from the outside as well.

Salmonella can survive sunny-side-up, over-easy, and scrambled cooking methods.

In order to keep Salmonella from multiplying an egg must cooled to lower than 45 degrees shortly after being laid and must be kept constantly at that temperature.  If an egg needs to be washed the temperature of the water should be 20 degrees warmer than the egg.  If not the contents of an egg will contract and produce a vacuum inside the egg that will pull in more contaminates.  Egg shells naturally have a protective coating to keep bacteria from penetrating the porous shell, so washing should be gentle.  

The problem with backyard chicken farmers is that they may day jobs and could leave eggs out to be collected for hours in the hot summer sun.  This could be a breeding ground for contamination.

In U.S. commercial egg production, approximately 95% of laying hens are confined in battery cages, small wire enclosures that afford each hen roughly 430 cm2 —a space smaller than a single sheet of letter-sized paper. These cages are placed side-by-side in rows and stacked in tiers commonly 4-8 levels high. Each cage may hold 5-10 birds.  Hundreds of thousands of hens may be confined within a single building.