Kevin Lawrence

Citation

Thesis Title
The epidemiology of Theileria Orientalis Ikeda type in New Zealand

This research was primarily conducted to document and understand the Theileria orientalis Ikeda type epidemic, which has been well established on North Island cattle farms since 2012. Mr Lawrence summarised the epidemiology of the initial outbreak, presented the results of a prevalence study, and analysed the common history, haematology, and biochemistry changes associated with infection. Two observational field studies were conducted. The first investigated the vertical transmission of T. orientalis infection from dam to calf and the second investigated the temporal dynamics and effects of T. orientalis infection in three dairy herds. The results showed that that the spread of infection between properties was a combination of infected cattle movements and the local spread of infected ticks. It also showed that vertical transmission of infection from dam to calf is unlikely and that disease spreads rapidly through herds, with up to 26% of cattle becoming anaemic. Furthermore, disease is less severe in calves than adults, and less severe in endemic regions compared to non-endemic regions.

Supervisors
Professor Bill Pomroy
Dr Ian Scott
Professor Tim Carpenter