1. Department of General and Clinical Pathology, Faculty of Veterinary Medicine, Trakia University, Stara Zagora 6000, Bulgaria
2. Department of Veterinary Anatomy, Histology and Embryology, Faculty of Veterinary Medicine, Trakia University, Stara Zagora 6000, Bulgaria
3. Clinical Laboratory, University Multiprofile Hospital for Active Treatment “Professor Stoyan Kirkovich”, Stara Zagora 6000, Bulgaria
4. Department of Social Medicine, Health Management and Disaster Medicine, Faculty of Medicine, Trakia University, Stara Zagora 6000, Bulgaria
5. Department of Veterinary Microbiology, Infectious and Parasitic Diseases, Faculty of Veterinary Medicine, Trakia University, Stara Zagora 6000, Bulgaria
6. Independent Researcher, Surrey CR3 5ZD, UK