Reproductive inefficiency is one of the most costly and production limiting problems facing the livestock development in Africa. Reproductive performance is influenced by a number of important factors, among which are infectious diseases, which result in lost production. Research in these diseases is critical in order to overcome these shortfalls.The objectives of the following studies were to provide a more in-depth epidemiological analysis of infectious reproductive diseases in Sub-Saharan Africa and further investigate the cytokine environment and molecular factors involved in the innate immune response of the bovine reproductive tract to infectious agents which can play such an important role in livestock production in Africa, in particular Tritrichomonas foetus. The prevalence of important infectious reproductive diseases in a single herd using serology was investigated. Significantly, high seroprevalence of infectious bovine rhinotraechitis and trichomoniasis was demonstrated. The presence of coxiellosis, neosporosis, bovine viral diarrhea virus, and bovine herpesvirus-4, was demonstrated but not serological evidence of brucellosis. Significant associations were found between the seroprevalence of the different viral pathogens but no such association was noted between the other pathogens. The long calving interval in this herd could be due to the presence of these pathogens. Among the diseases we identified, we further studied trichomoniasis (T. foetus) and the host immune response in a mouse model. Serum and reproductive tissues for Th1 and Th2 cytokines (specifically INF-ã, TNF-á, IL-2, IL-4, and IL-5) via flow cytometry after 5 days of T. foetus infection were analyzed. Mice of varying ages which had different susceptibility to T. foetus infection were used to assess whether a Th1 or Th2 cytokine environment was significantly associated with successful infection. Both Th1 and Th2 cytokines (TNF-á, IL-4 and IL-2) were shown to be significantly altered in infected animals. Lastly, by using PCR and IHC techniques, the presence of the novel dual oxidase molecules (DUOX 1 and 2) in the reproductive tract of cows and in bovine endometrial and trophoblast cell cultures was documented. However, there was no significant difference in DUOX 1(P=0.296) or DUOX2 (P=0.480) expression in T. foetus infected cells versus their respective controls. In conclusion, several important infectious diseases in Ghanaian cattle which may affect reproduction, not the least of which is trichomoniasis, were detected. Further, it was demonstrated that the early infection has both Th1 and Th2 cytokine involvement and that while present in the reproductive tract, there is no evidence that the DUOX molecules play a role in early resistance, but they may be important at other time points.
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