New Insights Into Postpartum Uterine Diseases Of Dairy Cows
Uterine diseases of dairy cows have a negative impact in the dairy industry because they are prevalent, contribute to economic losses and are an animal welfare issue. This dissertation was conducted to advance our knowledge of uterine diseases of dairy cows. A series of studies was conducted to: i) Develop new strategies to better diagnose endometritis, ii) Advance the understanding of the intrauterine microbiota associated with the presence of uterine diseases, iii) Evaluate the association between the cow's immune system and uterine diseases, and iv) Evaluate different strategies to prevent and treat uterine diseases, and improve reproductive performance. Chapter 2 described that uterine lavage sample optical density measured at 620 nm can be used as a diagnostic tool for clinical endometritis. In Chapter 3 and 4, it was reported that intrauterine treatments of mannose or a bacteriophage cocktail against E. coli, and intrauterine infusion of dextrose, were ineffective to prevent or treat uterine diseases. Chapter 9 describes that subcutaneous immunization with components of Escherichia coli, Fusobacterium necrophorum and Trueperella pyogenes prevented puerperal metritis. Chapters 5, 6, and 7 describe three studies evaluating the benefits of injectable trace mineral supplementation (ITMS) during the transition period. ITMS improved mammary gland health, decreased clinical endometritis incidence, improved the antioxidant status of cows, and decreased the intrauterine presence of known intrauterine pathogens. Findings from Chapter 3, 7, and 9 reinforces the importance of E. coli, T. pyogenes, and F. necrophorum as etiological agents of uterine diseases. The first complete genome sequence of Trueperella pyogenes is reported in Chapter 8. Findings from chapter 9 imply that adaptive immunity is playing a role in the uterine defense, and that immunoglobulins are protective against uterine bacterial infection. This is also supported by findings from Chapter 10, which describes that higher blood levels of natural antibodies are positively associated with postpartum uterine health. In summary, this dissertation contributed to the current knowledge on several aspects of postpartum uterine diseases of dairy cows, but further research is needed to advance the knowledge on the pathogenesis of uterine diseases, and to develop better strategies to prevent, and treat those diseases.
Uterine diseases; Dairy cows; reproduction
Gilbert,Robert Owen; Butler,Walter Ronald; Nydam,Daryl Van
Ph. D., Animal Science
Doctor of Philosophy
dissertation or thesis