On August 3rd NAEF responded to the Washington Post article about “Happier Chickens”. The WaPo author concluded erroneously that chickens are “happier” when they no longer in cages, but NAEF felt it must strive to correct her misconception about the way eggs should be produced.
I enjoyed reading the article in the July 31st issue of the Washington Post "Are Chickens Happier When They're Cage-Free - It's Hard to Tell."
It's true there are trade-offs in any production system. Perhaps a few facts from the recent study conducted by the Coalition for Sustainable Egg Supply will help. The co-director, Dr. Joy Mench from University of California-Davis, reported the following from that study at the International Poultry Production and Processing Exposition in Atlanta, GA on January 26, 2016:
- 1.Total accumulated mortality was highest in the aviary (cage-free) system (11.5 percent), due to aggressive pecking and cannibalism. It was 4.7 percent in conventional cages.
- 2.Bone strength was lowest in conventional cages due to lack of exercise.
- 3.Using conventional production as a baseline, aviary production was 36 percent higher inof the eggs.
- 4.The aviary system had dust levels 8-10 times higher than other systems.
- 5.The aviary system resulted in high worker exposure to endotoxin dust particles and reduced lung function by the end of a shift.
- 6.The aviary system also presented ergonomic challenges; hens laying in litter resulted in a lot of crawling around for employees and potential respiratory and infection hazards.
- 7.Keel bone breakage was highest in the aviary system.
One of the comments addressed food safety. Eggs laid on the ground where manure is also located have an increased likelihood of bacterial contamination. Below are two scientific journals substantiating these findings:
The Journal Poultry Science in 2011 [90, pp. 1586-1593] published "Comparison of shell bacteria from unwashed and washed table eggs harvested from caged laying hens and cage-free floor-housed laying hens." This study found that the numbers of bacteria on eggs was lower in housing systems that separated hens from manure and shavings.
Conventional cages allow the feces to drop through the screen floor whereas in cage-free systems, the eggs are laid in the same general area for manure. The potential for contamination is increased.
These results were confirmed in the Journal Food Control published a study June 17, 2014 entitled "Microbiological Contamination of Shell Eggs Produced in Conventional and Free-Range Housing Systems" The conclusions state "Battery caged hens (conventional cages) are standing on wire slats that allow feces to fall to a manure collection system beneath the hens. Conversely, free-range hens (cage-free) laid their eggs in nest boxes on shavings and the eggs remained in contact with hens, shavings and fecal material until they are collected.
The longer contact time with free-range hens, shavings and feces would explain the higher enterobacteriaceae counts (pathogenic bacteria) on free-range eggs as compared to battery caged eggs."
When considering all the trade-offs including cannibalism, diseases, and food safety, I'm happy that today's modern egg farmer has learned to produce a safe, wholesome egg in a modern cage system.