1. Department of Agricultural, Food, Environmental and Animal Sciences, University of Udine, Via Delle Scienze 206, 33100 Udine, Italy
2. Department of Veterinary Medicine, University of Perugia, Via S. Costanzo 4, 06126 Perugia, Italy
3. Centre for Perinatal and Reproductive Medicine, University of Perugia, 06129 Perugia, Italy
4. Research Institute for Farm Animal Biology (FBN), Wilhelm-Stahl-Allee 2, 18196 Dummerstorf, Germany