Hen housing research examines worker health

Published on: Sep 26, 2013

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 the cage-free aviary house were exposed to higher levels of dust and bacteria than those working in the conventional cage or enriched colony house. The findings also bring "clarity" to the question of egg quality, as it was not impacted by hen housing system. This illustrates the multiple variables that must be considered when evaluating the sustainability of different egg production systems, CSES said.

Research on the sustainability of different production systems conducted by CSES will help inform policy makers, egg producers, food industry stakeholders and consumers who purchase eggs. The 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 environment aspects of the research were released in 2012. CSES said 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 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."

Among the three types of housing studied, the cage-free aviary system had consistently higher inhalable particle and inhalable endotoxins concentrations in spring, summer and winter, CSES said. Workers who had been in the aviary system had fewer changes in lung function between the beginning and end of work shifts than those in other systems, though not significantly so.

Many of these issues can be managed by workers wearing an approved respiratory mask (masks were available to all workers during the study). Less frequent mask use is significantly associated with lower lung function. Average mask use was higher for workers in aviary housing, which may have protected them from greater respiratory consequences than had they not worn them.

Measures of food safety and egg quality were taken as well. The quality of the eggs was assessed shortly after they were laid using multiple parameters, which were and found not to be impacted by hen housing system. Eggs from the three systems were further assessed at four, six and 12 weeks of cold storage to determine if housing system impacted the rate of egg quality decline. Findings showed that hen housing system did not impact the rate of egg quality decline. Therefore, 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, CSES said.

Researchers will finalize analysis of the research data on behalf of the coalition in 2014 with a final report available in 2015.

A complete overview of the Flock One research and preliminary results, including Animal Health and Well-Being, Food Affordability, Environment, Worker Health and Safety, and Food Safety and Quality, is available at http://www.sustainableeggcoalition.org.