The Library
Investigating the impact of antibiotic treatment on the dairy cow mammary gland microbiome
Tools
Wrigley, Helen (2022) Investigating the impact of antibiotic treatment on the dairy cow mammary gland microbiome. PhD thesis, University of Warwick.
|
PDF
WRAP_Theses_Wrigley_2022.pdf - Submitted Version - Requires a PDF viewer. Download (22Mb) | Preview |
Official URL: http://webcat.warwick.ac.uk/record=b3913204
Abstract
Mastitis, the inflammation of the mammary gland, is the most prevalent disease among UK dairy cattle, imposing a significant burden on animal welfare, food security and antibiotic use. It is complex disease, with over 140 bacterial species being identified as etiological agents and general dysbiosis of the mammary gland bacterial community also being associated with mastitis incidence. A major driver of antibiotic use in dairy cows is in the administration of an intramammary infusion antibiotic and a teat sealant at drying off. This is to treat and prevent mastitis over the dry period and into early lactation when cows are particularly susceptible to mastitis. For responsible and justified use of antibiotics the effect of therapy on the mammary gland microbiota and udder health in sub-clinical mastitis cases need to be understood. In this study high-throughput sequencing techniques were used to analyse the bacterial community from 1231 milk samples collected from the udder quarters of 40 cows, in 2 independent farm studies, over 11 time points across the dry period into early lactation. Conclusions drawn from the first herd directed the specific selection of samples to analyse in the second herd, allowing the impact of antibiotic therapy on the milk microbiota to be more explicitly addressed. Data analysis and statistical modelling revealed that cows receiving antibiotic therapy had a similar outcome in the udder health and diversity metrics of the mammary gland microbiota in early lactation compared to those cows receiving just teatsealant therapy. A highly diverse composition and a dynamic nature of the milk microbiota was reported in both farms and treatment groups. Reporting that rapid changes to the bacterial community can occur within udder quarters, over subsequent time points, just 1 to 2 days apart. This study demonstrated the complexity and difficulty in describing a normal, stable microbiota in the mammary gland. It also suggests, in the context of these two farms, more evidence is required to show that omission of antibiotic therapy at drying off would be detrimental to healthy cows or cows with sub-clinical levels of mastitis.
Item Type: | Thesis (PhD) | ||||
---|---|---|---|---|---|
Subjects: | Q Science > QL Zoology Q Science > QR Microbiology S Agriculture > SF Animal culture |
||||
Library of Congress Subject Headings (LCSH): | Mastitis, Antibiotics in veterinary medicine, Mammary glands, Lactation, Cattle -- Diseases | ||||
Official Date: | July 2022 | ||||
Dates: |
|
||||
Institution: | University of Warwick | ||||
Theses Department: | School of Life Sciences | ||||
Thesis Type: | PhD | ||||
Publication Status: | Unpublished | ||||
Supervisor(s)/Advisor: | Purdy, Kevin J. ; Green, Laura E. | ||||
Sponsors: | University of Warwick. School of Life Sciences ; Biotechnology and Biological Sciences Research Council (Great Britain) ; Midlands Integrative Biosciences Training Partnership | ||||
Format of File: | |||||
Extent: | 171 pages : colour illustrations | ||||
Language: | eng |
Request changes or add full text files to a record
Repository staff actions (login required)
View Item |