Completed Research Projects - Cattle
Bovine Pink Eye
Prevention and Treatment of Environmental Mastitis |
Bovine Pink Eye
Farm Animal & Veterinary Public Health Staff
Associate Professor John House
National Collaborators
25 Veterinary Practices from around Australia
International Collaborators
Dr John Angelos,
University of California, Davis
Masters Student
Mr Craig McConnell
Summary
Infectious bovine keratoconjunctivitis (IBK) is considered the most common ocular disease of cattle throughout the world. IBK is important both in terms of animal welfare and as a cause of lost production.
Despite the susceptibility of the causative bacterium Moraxella bovis, to a large number of antimicrobial compounds the treatment of affected cattle has many disadvantages and the prevention of IBK is therefore preferable. M. bovis virulence factors include the production of leukotoxin, protease, and β-hemolysin along with the presence of fimbriae on the bacterial cell surface that play a role in adherence. M. bovis fimbrial proteins act as immunogens and vaccination with isolated fimbriae stimulates bovine anti-fimbrial antibodies. However, strains of M. bovis are known to differ in their fimbrial antigens, with two types of fimbriae identified along with at least seven distinct serogroups of fimbriated M. bovis. Efficacious application of fimbrial based IBK vaccines requires production of a polyvalent vaccine targeting specific regional isolates.
The aims of this project are:
- To conduct a survey of Moraxella bovis strains in Australia to determine the prevalence of different serotypes across the country.
To determine which virulence attributes are common to most isolates.
To design a pink eye vaccine applicable to prevention of bovine infectious keratoconjunctivitis in Australia.
Source of Funding
Schering Plough Animal Health
Project Timeframe
Completed - January 2006
Prevention and Treatment of Environmental Mastitis
Farm Animal & Veterinary Public Health Staff
Associate Professor John House
Masters Student
Ms Lucy Shum
Summary
The prevalence of contagious mastitis in dairy cattle has dropped over the last 20 years. Environmental mastitis subsequently accounts for the largest proportion of intramammary infections and the associated losses in production. Surveys of mastitis conducted in Australia have reported that Streptococcus uberis is the most frequent environmental mastitis pathogen and suggest that coliform mastitis is relatively infrequent in Australian dairy cattle. These prevalence surveys have been conducted in Victoria and reflect the prevalence of disease in pasture fed dairy cattle.
Over the last 10 years there has been a steady and continuing trend toward intensification of the dairy industry with more farms providing supplementary feeding and some farms feeding total mixed rations similar to dairy production systems in Europe and the United States. Working with intensive dairy production systems in NSW we have observed a higher incidence of coliform mastitis than reported in Victorian surveys.
The objective of this study is to determine the prevalence of different mastitis pathogens on intensive dairies in NSW and to investigate the interaction between diet and environment on the major groups (coliforms and streptococci) of environmental pathogens.
Source of Funding
Pfizer Animal Health
Project Timeframe
January 2004 - December 2006