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ARS Home » Southeast Area » Athens, Georgia » U.S. National Poultry Research Center » Egg and Poultry Production Safety Research Unit » Research » Publications at this Location » Publication #390687

Research Project: Reducing Pathogen Contamination Risks and Improving Quality Attributes of Eggs and Egg Products through Housing System Management and Egg Handling Practices

Location: Egg and Poultry Production Safety Research Unit

Title: Laying hen production and welfare in a cage-free setting is impacted by the northern fowl mite

item JARRETT, RACHEL - Purdue University
item ERASMUS, MARISA - Purdue University
item MURILLO, AMY - University Of California
item SCOLES, KAILYNN - Purdue University
item ROBISON, CARA - Michigan State University
item Jones, Deana
item KARCHER, DARRIN - Purdue University

Submitted to: Journal of Applied Poultry Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/29/2022
Publication Date: 9/1/2022
Citation: Jarrett, R., Erasmus, M., Murillo, A., Scoles, K., Robison, C., Jones, D.R., Karcher, D.M. 2022. Laying hen production and welfare in a cage-free setting is impacted by the northern fowl mite. Journal of Applied Poultry Research.

Interpretive Summary: As the US egg industry shifts to extensive housing systems for laying hens, infestation of ectoparasites such as northern fowl mites (NFM) have begun to occur. A study was conducted to determine the impact of NFM infestation on egg production and hen welfare. The key outcomes of the study were: 1. NFM negatively impact percent livability, body weight, and result in an increase in feather damage and decreased hen-day percentage when infestation levels are consistent and high; 2. Environmental and management differences in cage-free systems play a role in NFM populations, how they spread, and how they impact flock welfare and production; 3. Cannibalism challenges in Trial 1 and egg eating behavior in Trial 2 were limitations to this study, as they impacted production numbers, but are a reality of small-scale and commercial cage-free egg production; and 4. Variations of cage-free systems could result in different hen welfare and production findings depending on management, hen genetic strain and complexity of the system.

Technical Abstract: The northern fowl mite (Ornithonyssus sylviarum) is a common blood-feeding ectoparasite of poultry that can cause decreased egg production and reduced hen welfare. The blood-feeding behavior of the northern fowl mite (NFM) elicits a host immune response in hens that leads to decreased egg production, anemia, irritation to flocks and personnel, profit loss, and death to hens in extreme cases. As the egg industry moves toward extensive housing systems, it is important to consider management implications of the switch, such as the impact of NFM infestations. In the present study, hens were infested with NFM in two trials. Production and welfare parameters were monitored throughout the duration of the studies, beginning at 18 weeks of flock age and ending at 47 and 49 weeks of age for Trials 1 and 2, respectively. A cannibalism issue in Trial 1 resulted in a loss of hens by the end of the trial and a low overall NFM infestation, while Trial 2 had consistent NFM infestation levels. In Trial 1, NFM negatively affected hen-day percentage, body weight, and feather coverage of some areas. In Trial 2, the NFM infestation negatively affected hen-day percentage, mortality, body weight, shell thickness, and feather coverage of some areas.