13TSB_ACT: Evaluation of MALDI-TOF-MS to differentiate sub species of the pathogen S uberis to provide an improved approach to mastitis control

Bovine mastitis is an inflammatory disease of the udder and is a major barrier to the sustainability of dairy farming
worldwide. The health, welfare, economic and environmental impacts of bovine mastitis are severe. It is the most common
cause of on-farm death and premature culling. With an incidence rate of clinical mastitis of 60/100 cows/year more than
one million cows are affected per annum in the UK alone. Mastitis treatment and control accounts for over 30% of all
antibiotic use in dairy cattle. Annual losses exceed £170M in the UK; 38% of the total direct costs of disease. Therefore
mastitis substantially reduces the efficiency of dairy farming and an increased rate of culling of mastitic animals adversely
affects the environment and the drive towards national and international food security, while antibiotic use in cattle may
also spread resistance to bacteria that impact on human health.

Mastitis is caused by a bacterial infection; the bacteria enter the mammary gland via the teat canal. The central premise of
mastitis control is to minimise the risk of infection by reducing transmission of bacterial pathogens into the udder. In order
to control mastitis, it is necessary to understand how and when bacterial infections occur and how the pathogens cause an
infection. Although only a few species of bacteria commonly cause bovine mastitis, it is now recognised that sub species
(strains) of these bacteria behave in different ways in terms of disease transmission and outcome. The aim of this research
is to develop a method to differentiate strains of the most common mastitis pathogen, S uberis, according to their disease
transmission characteristics. To do this, a modern, high throughput method of mass spectrometry (matrix-assisted laser
desorption ionization/time-of-flight mass spectrometry - MALDI-TOF-MS) will be used to differentiate strains of S uberis.
These strains will be grouped according to how they cause mastitis and the outcome of disease. This information will then
be used to inform mastitis control programmes which will include reduced use of antibiotics on farm.

If successful, his research will pride a new and improved approach to mastitis control in dairy cows. This would be to the
benefit of dairy farmers (reduced disease costs), veterinary surgeons and advisors (improved ability to advise on mastitis
control), the dairy industry (improved sustainability, welfare and image by reducing mastitis) and consumers (improved cow
welfare and food security).

Bovine mastitis is the foremost endemic infectious disease of dairy cattle and remains a major challenge and threat to the global dairy industry. Streptococcus uberis is the most common pathogen associated with bovine mastitis. In order to effectively treat and control S uberis mastitis, more knowledge is required about the pathogen; how it is transmitted and how it is managed effectively. It is now known that different sub species (strains) of S uberis have different transmission and infection characteristics with different disease outcomes. The objective of this project is to provide, for the first time, a new, fast and cheap technology for farmers and clinicians to identify different sub species of S uberis that align with specific infection characteristics. This is innovative because it will provide a new technological approach of high throughput pathogen characterisation at sub species level, to greatly improve commercial mastitis treatment and control.

Possible results of this research include;

A) An association between mass spectral profiles of strains of S uberis and their clinical behaviour

B) From this, a method to predict clinical outcome of different sub species of S uberis which will be used to improve
mastitis management by identifying most appropriate strategies for mastitis management in given farm circumstances.

Main beneficiaries of the research will be;

1. Farmers
2. Veterinary surgeons and farm advisors
3. Other milk quality/testing laboratories
4. The dairy industry
5. Consumers
6. UK PLC

How will they benefit?

1. Farmers - through improved mastitis control leading to significant financial savings and working conditions
2. Veterinary surgeons and farm advisors - through being able to market an enhanced approach to mastitis control
3. Other milk quality/testing laboratories - through use the strain typing service via QMMS
4. The dairy industry - through improved sustainability, welfare and image by reducing mastitis
5. Consumers - through consuming a product associated with improved cow welfare and with improved farming
sustainability
6. UK PLC - through improved efficiency of dairy farming and economic returns from selling the technological advancement