Considerable discussion has taken place in the egg industry over the years as to the relevance of evaluating the performance of strains of laying hens under a single management system. This type of testing was created as early as 1911 in the U.S. to compare the performance of different strains of laying stock to help producers select the best strain of hens for their laying operations. Later, a format was proposed and developed for utilizing such tests in research programs by Hagedoorn. The new format was instituted in Holland to help producers evaluate laying stocks.

In the old days, these were referred to as Random Sample Tests which were organized formally in 1947-48 in California with a dramatic increase in U.S. tests over the next 15 years. Initially, some of the tests may not have been so random in nature which resulted in the organization of the “National Committee on Random Sampling Poultry Testing” within the USDA-AMS. This committee operated and published annual reports until 1979, at which time the committee was dissolved. From a peak of 22 official Random Sample Tests in 1962, the number of tests declined in the U.S. until a single test remained in North Carolina.

Testing housing alternatives

Fortunately, the director of the North Carolina test at the time, Dr. John Carey, shifted the focus of the test to include environment and management as main effects in the research as well as the hen strain effects. Carey stated, “The extensive changes in housing and management of layers require egg producers to seek viable means to continue to produce eggs using the most up-to-date understanding of the relationships between genetics and management.” With the reorganization to the North Carolina Random Sample Test into the NC Layer Performance and Management Test (NCLP&MT) there was much greater interest in the results, because it allowed producers to look at how the various strains performed at different densities and under different management factors within the same cage environment.

Cage density became very important as the egg industry progressed through the initial turbulence of the animal welfare program development. In the early 2000s, as the conventional cage systems reached the end of their life cycle, remodeling of the facilities for the NCLP&MT allowed for the comparison of housing systems to ensure the relevance of the test’s results to the egg industry. The initial remodel in 2005 resulted in the installation of conventional cages with manure belts, and then in 2007 the first range facility was developed. This was followed in 2010 with the first cage-free floor facility at the location since 1977, to address the industry needs to re-examine cage-free production management. Later, one house was remodeled to utilize a cage-free slat/litter management system.

Finally, in 2013 the last conventional cage facility was remodeled to include the new enriched environmental housing system, which now allows the evaluation of five different production systems used in the egg industry. All the while, the NCLP&MT continues the goal of objectively comparing the impact of hen management on the production characteristics of a wide range of available genetic stocks.

The egg industry of today is facing a shift back to colony production systems as well as to cage-free and free range systems. Learning how the current laying hen strains react in these different systems is important for the industry.

As researchers, we need to have access to research facilities where external variables are minimized and where all of the animals are treated in the same manner regardless of the strain of the hen or the housing environment. This allows us the ability to differentiate and determine the interactions between hen strain and housing systems. Another important aspect of the NCLP&MT is the collaboration of researchers with different perspectives and research interests. The value of the controlled production environment is recognized by the research community leading to collaborative projects that can assess hen health and well-being, egg safety and quality, as well as environmental impact.

Over 100 publications

However, in this day and age, many people are asking, “What have you done for me lately?” As a controlled-environment research facility, there have been more than 100 peer review papers published as a result of the research conducted in the NC Layer Test facilities in journals such as Poultry Science, the World’s Poultry Science Journal, the Journal of Applied Poultry Research and the Journal of Food Protection. Along with the production research, the spent fowl have contributed to the body of knowledge related to ovarian cancer prevention in the Journal of Gynecologic Oncology and Lab Animal. Additionally, 61 Extension Reports detailing the influence of the production environment and the various strains of laying stock available in the U.S. have been written and published.

More importantly, due to the NCLP&MT, research on egg processing and cooling has helped improve our understanding of egg quality and safety. As a result of the resources available, a greater understanding of how processing influences the heating and cooling of the egg has been developed. This information was a component in the risk assessment model for egg safety conducted by USDA-FSIS.

An uncertain future

In the future, the U.S. faces challenges from the current trend towards more egg production from cage-free and free-range systems as well as a possible shift to enriched colony cages. The need for understanding of the interactions between the strains of laying hen, housing systems, nutrient needs, and egg quality and safety continues due to the changes in performance of our laying hen strains as a result of the genetic selection carried out by commercial egg-type breeding organizations.

Dietmar Flock, former director of genetics for Lohmann Tierzucht in Cuxhaven, Germany, said that the gradual change in management factors in the NC tests, including current but also promising and innovative systems, should be of special interest for egg producers who will need to replace old facilities. Repetition of some of those factors over a number of tests also allows future researchers to analyze multiple years of data with an assurance of the contingency of the matrix of treatment effects.

The issues facing the poultry industry today are many and they are very diverse in nature. Solutions to those issues require that researchers with different interests and perspectives be able to conduct and report their findings from facilities that are comparable to those used by the commercial egg industry. The NCLP&MT has created a wide array of multi-institutional, multi-discipline, and multi-resource groups of researchers to address these issues and to examine the interrelationships these variables may have on productivity, economic response, hen welfare, egg quality and egg safety.

The mission of the NCLP&MT is to provide the best information related to layer strain performance and the impact of the production environment on the laying hen. We have striven to keep the production systems in line with current industry practice, as well as be ahead of the curve in problem-solving related to pullet and hen management. North Carolina’s Piedmont Research facilities are one of the few facilities in the world that are available for the conduct of relevant management and strain research for the egg industry.

As with any production facility, everything does not always operate according to plan at the Piedmont Research facility. Occasionally, instances outside of protocol will occur, but all of the animals are exposed to the same scenarios. When such situations (such as power outages or disease breaks, etc.) occur, a great deal about hen management and how the commercial egg industry may be able to avoid similar problems in the course of producing eggs is learned. The NCLP&MT is also a training ground for undergraduate internships and graduate students who will become the future researchers and egg industry leaders.

The NCLP&MT would not exist without the continued support of the primary breeders, who participate in the test and provide input into the operations of the test. In addition, the North Carolina Department of Agriculture and Consumer Services provides the research station facilities and staff to conduct and maintain the flocks, and the efforts of the researchers and their institutions, who participate via travel, sample collection and associated analyses. The holistic approach of the NCLP&MT is unique and serves as a testament to the collaboration of academia, state and federal government, allied industry and the egg industry to provide unbiased results for very small to large egg producers alike.