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ARS Home » Midwest Area » West Lafayette, Indiana » Livestock Behavior Research » Research » Research Project #426095

Research Project: Thermal Perches as Cooling Devices for Reducing Heat Stress in Caged Laying Hens-Purdue

Location: Livestock Behavior Research

Project Number: 5020-32000-013-11-A
Project Type: Cooperative Agreement

Start Date: Oct 1, 2013
End Date: Jul 30, 2018

The aim of the proposed work is to develop a novel method to safeguard hen welfare by reducing heat stress (HS) effects. The objectives are 1) to determine if cooled perches improve thermal comfort and welfare for caged hens during hot weather, 2) to examine if cooled perches prevent heat stress-induced behavioral and neurophysiological changes, improving heat adaptation in caged hens, and 3) to conduct engineering and economic analyses of the costs and maintenance of cooled perches and perform sensitivity analyses to key economic parameters.

Hens, 17 wk of age, will be randomly assigned to 3 treatments: 1) cages with water cooled galvanized steel circular perches (400 mL/min flow rate chilled to 10o C), 2) cages with ambient air-equilibrated galvanized steel circular perches, and 3) conventional cages without perches. Two trials lasting 12 months will be initiated in early April during each of 2 consecutive years using poultry housing with standard ventilation equipment. The hen housing facility will not be evaporatively cooled during the summer to simulate typical housing for laying hens in the Midwest. To simulate a production environment, water cooling in treatment 1 will only be used during hot weather (ambient temperature of 29o C or greater) when hens peak in egg production. If the summer seasons turn out to be mild, then measures will be used to induce heat stress (32o C ambient) without causing mortality by use of mobile heaters. All hens will be evaluated for physical condition (skeletal and foot health and feather quality); biological phenomena (body weight, egg production, egg weight, shell quality, feed efficiency, and necropsies on all mortality); and well–being indicators (body temperature as well as behavioral and endocrine responses). Economic and environmental impacts will be assessed.