Archives Des Sciences Vol 66, No. 5;May 2013 139 ISSN 1661-464X ELISA Serum Corticosterone Determination in Rabbits Used in Experimental Purposes Romeo T. CRISTINA (Corresponding author) Veterinary Pharmacology Department, Faculty of Veterinary Medicine Timisoara, USAMVBT, 300645, No. 119, Calea Aradului, Timisoara, Romania E-mail: rtcristina@yahoo.com Adina BAIAS Veterinary Pharmacology Department, Faculty of Veterinary Medicine Timisoara, USAMVBT, 300645, No. 119, Calea Aradului, Timisoara, Romania E-mail: adina.baias@gmail.com Camelia TULCAN Internal Diseases Department, Faculty of Veterinary Medicine Timisoara, USAMVBT, 300645, No. 119, Calea Aradului, Timisoara, Romania E-mail: camelia_tulcan@yahoo.com Doru MORAR Internal Diseases Department, Faculty of Veterinary Medicine Timisoara, USAMVBT, 300645, No. 119, Calea Aradului, Timisoara, Romania E-mail: doru.morar@yahoo.com Abstract In experimental models used in research an important role has to reduce as much as possible variables that don’t depend on the experimental procedure and which influencing animal welfare and research results. The usually stress factors from animal laboratory facility are light and noise. First hormone released from the action of stress factors are glucocorticoids: cortisol and corticosterone. The aim of presented research was to determine serum corticosterone levels by ELISA technique in a group of adult rabbits exposed 24 hours to stress factor, represented by noise. We obtained corticosterone concentrations mean values between 23,000 and 35,000 pg/ml, this value of corticosterone being, in our opinion, the interval which indicates the noise stress presence in laboratory rabbits. Keywords: ELISA, serum corticosterone, rabbit, noise, stress 1. Introduction 1 The assessment of laboratory animal welfare is perceived through the absence or presence of the stress state. Appearance of stress is due to the hormonal changes that occur, as a result of the influence of stressors. From the abundance of stressors (noise, light, high or lower temperature and humidity etc.) noise can cause great discomfort and stress in an animal’s laboratory facility environment (Conour et al.2004). Light conditions in facilities are designed more to help people that work with laboratory animals, than to satisfy the animals light requirements. In animal facilities the light schedule is either constant or follows a light: dark program. Photoperiod and light intensity affects the animal welfare. For example, fluorescent