Discussion

Animal African Trypanosomiasis (AAT) affects livestock production in sub-Saharan Africa with prevalence estimated between 5 – 50% in Ghana. This study established the levels of serum biochemical parameters and cytokine profiles in naturally infected cattle over a period of six months. Nested Internal Transcribed Spacer (ITS)-based PCR and sequencing were used to characterize trypanosome infection in cattle (n = 40) at two areas, Adidome and Accra, of different endemicities. Levels Creatinine, Cholesterol, Alkaline phosphatase (ALP), Alanine aminotransferase (ALT), Total bilirubin and Total protein, and cytokines (IL-10, IL-4, IFN-γ, TNF-α and IL-12) were measured in serum samples collected every 4-5 weeks over 6 months. The predominant trypanosomes detected in Accra (non-endemic) and Adidome (endemic) were Trypanosoma theileri and Trypanosoma vivax respectively. Serum biochemical parameters were similar between infected and uninfected cattle in Accra. Infected cattle at Adidome had significantly higher levels of ALP (p = 0.02) and Total Bilirubin (p = 0.04) and significantly lower levels of cholesterol (p = 0.02) at specific time points. At basal levels and during infection, significantly higher pro-inflammatory/anti-inflammatory (Th1/Th2) cytokine ratios were observed in cattle at Adidome compared to Accra. Levels of IL-10 and TNF-α were significantly elevated in infected cattle in Accra. These findings suggest that, cattle in an endemic area repeatedly infected with parasites of different species and different antigenic types demonstrate high pro-inflammatory (Th1) immune response whereas cattle in a non-endemic area with chronic infections demonstrate high anti-inflammatory (Th2) immune response.