Abstract
1Department of Veterinary Pathology and Public Health, Faculty of Veterinary Science New Zealand, and Instituto Di Microbiologia, Universita Degli Studi De Trieste, 34127 Trieste, Italy
2Department of Microbiology and Genetics, New Zealand, and Instituto Di Microbiologia, Universita Degli Studi De Trieste, 34127 Trieste, Italy
3Massey University, Palmerston North, New Zealand, and Instituto Di Microbiologia, Universita Degli Studi De Trieste, 34127 Trieste, Italy