Authors
Ivanka Lazarova
Faculty of Veterinary Medicine, Trakia University, Stara Zagora, Bulgaria
Dobromir Dobrev
Bulgaria
Gradimir Gradev
Stara Zagora, Bulgaria
Rusko Petrov
Stara Zagora, Bulgaria
Stoycho Stoychev
Bulgaria
Ivaylo Klisurov
Stara Zagora, Bulgaria
Dimitar Demerdzhiev
Bulgaria