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ARS Home » Southeast Area » Athens, Georgia » U.S. National Poultry Research Center » ESQRU » Research » Publications at this Location » Publication #352531

Research Project: Evaluation of Management of Laying Hens and Housing Systems to Control Salmonella and Other Pathogenic Infections, Egg Contamination, and Product Quality

Location: ESQRU

Title: Early molting of layers: Impact on egg shape and shell quality

item Miller, Anna
item Jones, Deana
item ROBINSON, CARA - Michigan State University
item REGMI, PRAFULLA - Purdue University
item EBERLE, KRISTA - North Carolina State University
item KARCHER, DARRIN - Indiana University-Purdue University

Submitted to: Poultry Science Association Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 5/1/2018
Publication Date: 7/23/2018
Citation: Miller, A.M., Jones, D.R., Robinson, C., Regmi, P., Eberle, K., Karcher, D.M. 2018. Early molting of layers: Impact on egg shape and shell quality. Poultry Science Association Meeting Abstract. 97:14.

Interpretive Summary:

Technical Abstract: When quarantine zones are established in response to poultry disease outbreaks, such as Highly Pathogenic Avian Influenza (HPAI), flocks within in the zone may not be moved. Pullet rearing facilities in particular can be greatly impacted. The current study was conducted to explore options for holding pullets for an extended period in the rearing system during such a quarantine period. A flock of W-36 pullets were reared in a cage-free housing system from 0 – 16 wks of age. At 17 wks, pullets were assigned to a treatment: Control (CN) – moved into aviary laying facility following commercial practices; Enriched (EN) – stimulated to lay eggs in the pullet facility, perches and nest boxes provided; Molted (MT) – stimulated to lay eggs in the pullet facility, at 10% production molted; and Non-molted (NM) – stimulated to lay eggs in the pullet facility, no enrichments provided. At 25 wks of age, all hens were housed in commercial aviary housing and egg shape and shell quality characteristics were monitored weekly through 29 wks of age. Each week, 36 eggs/treatment were assessed for: weight, length, width, shape index, volume of shell, specific volume, percent length at maximum width, shell strength, shell elasticity, and shell thickness. A generalized linear model was utilized for statistical analysis. Average egg weight across all treatments increased 2.24 g over 4 wks (P < 0.01). While egg length increased (P < 0.0001) with hen age, the overall change was < 1 mm and not easily perceivable by the human eye. The percent egg length at maximum width decreased with hen age (P < 0.001) gradually decreasing 1% of the total egg length between 25 and 29 wks of age. Hen age and treatment interactions (P < 0.05) existed for egg width, volume of shell, specific volume, and shell thickness. Generally, CN and MT treatments produced eggs with similar, high quality shells. Early molting of pullets does not appear to negatively impact egg shape or shell quality in commercial cage-free aviary housing systems.