1. Department of Animal Science, Polytechnic University of Valencia, Camino de Vera s/n, E-46022 Valencia, Spain
2. Poultry Production Department, Faculty of Agriculture, Kafr El-Sheikh University, 33516 Kafr El-Sheikh, Egypt
3. Genetica i Millora Animal, Institut de Recerca i Tecnologia Agroalimentàries, Torre Marimon s/n, E-08140 Caldes de Montbui, Barcelona, Spain