Abstract
AIM: To survey the dairy cattle population in New Zealand for the presence or absence of Mycoplasma bovis.
METHODS: A random cross-sectional survey of bulk tank milk from dairy herds in New Zealand based on regionally proportioned sampling, weighted towards herds with a high bulk tank milk somatic cell count (SCC) was used to detect M. bovis at a between-herd prevalence of 2%, with 99% confidence. Bulk tank milk samples collected on-farm were tested using a nested M. bovis PCR, and bacteriological culture employing enrichment in mycoplasma broth and direct plating onto mycoplasma agar.
RESULTS: Mycoplasma bovis was not detected in any of the 244 bulk tank milk samples by either PCR or culture.
CONCLUSIONS: This survey provides further evidence that M. bovis is not present in the dairy cattle population in New Zealand.
Acknowledgements
The authors are very grateful for the support provided by Lindsay Burton, Dairy InSight, during the preparation phase of the survey, and for the permission to test samples granted by Roger Andela and Leo McIntyre from Fonterra Co-operative Group Ltd and Westland Milk Products, respectively. The authors would also like to thank Mrs Judy Forbes-Faulkner from the DPI & F Tropical & Aquatic Animal Health Laboratory, Townsville, and Mr Trevor Taylor from the Australian Animal Health Laboratory, Geelong, for the kind provision of M. bovis isolates from Australia. We would like to thank Dr Joanne Thompson for her support in initiating this work. Appreciation is extended to Margaret Malloch, Paul Jamieson and Gavin Scott from the South Auckland Independent Testing Laboratory who assisted with sample collection and submission, and David Williams from Fonterra who helped with use of the Fonterra Co-operative Group Ltd database.