Research Phd Theses

Research Phd Theses

Role of bovine non-aureus staphylococci in the regulation of Staphylococcus aureus growth and virulence and its potential implications for udder health

Staphylococcus aureus remains one of the most common causative agents of bovine mastitis because of its pathogenicity, contagiousness, capability to persist in the mammary gland, colonization of skin and poor cure rates when causing intramammary infections with the currently available therapies. On the other hand, non-aureus staphylococci (NAS) originating fromRead more

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Research Phd Theses

Biomarkers for bovine mammary gland involution and disease

At dry off, the mammary gland of the early dry cow undergoes a multitude of morphologic, immunologic, metabolic, and biochemical alterations known as mammary gland involution. During involution, the mammary gland is vulnerable to bacterial infection, particularly if milk leakage occurs. Increased risk of milk leakage and infection are associated with high milk production at dry off. Therefore, as advances in dairy cow management and fertility continue to increase milk production- more cows will be at risk for infection during early mammary involution. However, much remains unknown about optimizing mammary involution.

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Research Phd Theses

Impact of intramammary infections with non-aureus staphylococci on udder health and milk production in dairy heifers

Non-aureus staphylococci (NAS) have become the most prevalent cause of intramammary infections (IMI) in dairy cows in most parts of the world. The current body of literature on IMI caused by NAS has reported debatable and contradictory conclusions on their relevance for udder health and milk production. The aims of this thesis were to precisely estimate the impact of NAS IMI on somatic cell count (SCC) and milk yield (MY) at the quarter-level.

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Research Phd Theses

Selective antimicrobial treatment at dry off in dairy cows

Selective dry cow therapy (SDCT), in which only infected quarters/cows are treated with antimicrobials, constitutes an alternative to blanket dry cow therapy (BDCT) where all quarters of all cows at dry off receive antimicrobials, regardless of their infection status, for a more judicious use of antimicrobials. The objective of this thesis was to shed more light on targeted antimicrobial treatment decisions of infected quarters of cows at dry-off.

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