California Proposition 2 (2008) - Health and Food Safety

Health and Food Safety

Animals under stress, including the stress of intensive confinement, have compromised immune systems, and thus higher levels of pathogens such as Salmonella in their intestines.

According to the Centers for Disease Control and Prevention, "Stringent procedures for cleaning and inspecting eggs were implemented in the 1970s and have made salmonellosis caused by external fecal contamination of egg shells extremely rare. However, unlike eggborne salmonellosis of past decades, the current epidemic is due to intact and disinfected grade A eggs. The reason for this is that Salmonella enteritidis silently infects the ovaries of healthy appearing hens and contaminates the eggs before the shells are formed." Supporters of Proposition 2 claim that giving egg-hens more space can prevent this type of outbreak.

Contrarily, previous research suggests that eggs from modern housing systems have superior structural integrity in their shells, allowing for greater resistance to penetration by the Salmonella Enteritidis pathogen and decreasing the risk of egg contamination. On the other hand, the infection of free-range hens in the California study was caused via the "fecal-oral route through contamination of the feed through feces" from rodents that had easy access to these hens. In addition to being more vulnerable to exposure from rodents, free-range hens did not have the same level of manure management as those hens kept in modern housing systems. This is because the hens housed indoors had a manure belt that ran under their enclosures and transported the feces to collection receptacles, common to modern housing systems in California. On the other hand, according to a report by the Rural Industries Research & Development Corporation, the total number of bacteria on free-range eggs is 15 times greater than that found on eggs from modern housing systems. The Rural Industries report also postulates that the very construction of the indoor housing systems precludes the possibility of poultry and rodents existing closely, thereby potentially decreasing the possibility of cross-infection.

Supporters of Proposition 2 say that increased density of birds in battery cages leads to increased incidence of Salmonella in eggs. They also say that housing battery cages are very difficult to keep clean and are often are infested by large numbers of flies and rats.

However, opponents of Prop 2 say that modern housing effectively separates "feces and other fluids" from eggs, and that Prop 2 would "effectively ban modern housing". The opponents go on to say that "there has not been a reported case of salmonella linked to California eggs in nearly a decade" - but noting that people get salmonella from eggs that are produced outside of California every year . Their claim about salmonella cases linked to California eggs is supported by the U.S. Centers for Disease Control and Prevention.

An article entitled "The pros and cons of cages" published in the World's Poultry Science Journal in 2001 concludes that cages result in increased hygiene and lower incidence of disease related to feces, but can result in higher rates of metabolic disorders.

A recent undercover investigation of Norco Ranch (a Southern California egg ranch) was completed in August and September 2008. That investigation discovered badly decomposed chicken carcasses in the same cages with hens which were still laying eggs for human consumption. The organization that performed the undercover investigation, Mercy for Animals, released the undercover video to the public whereupon the video and the investigation received wide coverage in the news media. Proponents of Prop 2 imply that close confinement was a major factor in these bird's deaths. However, Prop 2 opponents assert that Norco Ranch was in violation of many California laws already in place.

A 2004 study of California egg farms in the journal Avian Diseases finds comparatively low Salmonella prevalence in indoor housing systems, commonly used in California, as compared to cage-free and free-range housing systems. The researchers state that this low Salmonella prevalence in California egg farms reflects the "distinct geographic, climatic, production and management characteristics" of the state's egg farms. 98 percent of egg farms adhere to the California Egg Quality Assurance Plan, which is a pathogen reduction program for Salmonella in California. The study states, "The highest prevalence in the free-range birds kept on the dirt floors." The California study notes that "feral cats, rodents, skunks, opossums, wild birds, and other wildlife" were seen near the free-range hens’ feeding areas, and that rodents "were considered to be the biological vectors and amplifiers" of salmonella on the egg farm in the study. A 2003 study from the Journal of Applied Microbiology and a study published in the journal Applied and Environmental Microbiology support the conclusion that wild animals are a significant and dangerous vector for salmonella.

Supporters of Prop 2 note that furnished cages for egg-laying hens have already been developed in Europe, which allow birds to move freely and display natural behaviors. The waste material in these systems is far less concentrated than with battery cages, and the animals are healthier and calmer with a stronger natural immunity to disease.

Opponents of Prop 2 note that a process called "traceback" is conducted by the Food and Drug Administration (FDA) and helps to maintain a safe food supply. The FDA's guidance to its staff for conducting tracebacks has sections entitled "Farm Investigations" and "Egg Processor/Packer Investigations," which contain detailed protocols explaining who goes on the farm, how the investigation is carried out, biosecurity procedures and other important steps to ensure that should an outbreak from eggs occur, the traceback would successfully reveal the original source. These opponents to Prop 2 say that California already has adequate and exemplary disease control techniques.