THE Coalition for Sustainable Egg Supply (CSES) released a preliminary analysis of its CSES Flock One research results for "Worker Health & Safety, Food Safety & Egg Quality" at the coalition's annual meeting Sept. 25 in Bloomington, Minn.
CSES said the findings show that workers in cage-free aviary houses were exposed to higher levels of dust and bacteria than those working in conventional cage or enriched colony houses. The findings also bring "clarity" to the question of egg quality as it was not affected by the type of hen housing system. This illustrates the multiple variables that must be considered when evaluating the sustainability of different egg production systems, CSES said.
The CSES research project is studying five aspects of sustainable egg production in conventional, enriched colony and cage-free aviary housing systems. Preliminary research results for the animal health and well-being, food affordability and environmental aspects of the research were released in 2012. CSES noted that it does not promote any specific housing system but encourages informed decision-making by stakeholders across the food system.
"Currently, the egg industry lacks comprehensive, commercial-scale research evaluating the various aspects of sustainability," said Dr. Joy Mench, professor of animal science at the University of California-Davis and co-director of the CSES research. "Evaluating the impact of hen housing systems based on these different variables will help provide the necessary research that is ethically grounded, scientifically verified and economically viable and, ultimately, in alignment with the desires of consumers."
Michigan State University professor of animal welfare Dr. Janice Swanson, also a CSES research co-director, added, "Completing the analysis of data from the first of two flocks and the addition of preliminary findings in these areas is a significant milestone in understanding the impacts and trade-offs associated with each system. What we observe here and in future data will greatly increase the knowledge about sustainable egg production available to egg producers and those responsible for making purchasing decisions."
Understanding differences in air quality and job requirements in different types of laying hen housing is important for providing a safe work environment, CSES said.
Among the three types of housing studied, CSES said the cage-free aviary system had consistently higher inhalable particle and inhalable endotoxin concentrations in spring, summer and winter. Workers in the aviary system had fewer changes in lung function between the beginning and end of work shifts than those in other systems, but not significantly so, the research found.
Many of these issues can be managed if workers wear an approved respiratory mask (masks were available to all workers during the study), CSES said. Average mask use was higher for workers in aviary housing, which may have protected them from greater respiratory consequences than if they had not worn them.
Understanding that specific job tasks can have an effect on worker health and safety, ergonomics were also evaluated, assessing the movements necessary to perform job functions in each of the barns and identifying possible risks, CSES said.
In conventional and enriched colony systems, loading and unloading cages during population and de-population required extreme body positions, including squatting for an extended time. In the aviary system, gathering eggs that had been laid on the floor also required extreme body positions, while crawling and lying on the floor exposed the worker to potential respiratory hazards and risk of infection to the hands and the knees, according to the research.
Food safety findings
CSES also measured food safety and egg quality. The quality of the eggs was assessed shortly after they were laid using multiple parameters, which were found not to be affected by the type of hen housing system.
Eggs from the three systems were also assessed at four, six and 12 weeks of cold storage to determine if the type of housing system affected the rate of egg quality decline, CSES said, reporting that the housing type did not affect the rate of egg quality decline.
Therefore, CSES concluded that current egg quality standards written for conventional egg production should adequately define egg quality for eggs from commercial cage-free aviary and enriched colony cages.
The participating researchers will finalize the analysis of the research data on behalf of CSES in 2014, and a final report will be available in 2015.
A complete overview of the Flock One research and preliminary results is available at www.sustainableeggcoalition.org.