H/L ratio as a measurement of stress in laying hens – methodology and reliability

Measuring the ratio of heterophils and lymphocytes (H/L) in response to different stressors is a standard tool for assessing long-term stress in laying hens but detailed information on the reliability of measurements, measurement techniques and methods, and absolute cell counts is often lacking.Laying hens offered different sites of the nest boxes at different ages were compared in a two-treatment crossover experiment to provide detailed...