Dynamic Patterns of Systemic Innate Immunity and Inflammatory Associated Factors in Experimental Caprine Coccidiosis

The present study was designed to assess the dynamic patterns of pro-inflammatory cytokines, including IFN-γ, TNF-α, IL-4, IL-6, acute phase protein (α1-acid-glycoprotein, AGP), and an inflammation associated factor (adenosine deaminase; ADA) following experimental caprine coccidiosis. Ten kids aging from 2 to 4 months were infected orally with 5×104 sporulated oocysts and 10 animals served as controls. Blood samples were collected in both groups before infection and at days 3, 7, 14, 21, 28, and 35 post-infection (PI), and the levels of above-mentioned factors were measured. IFN-γ, TNF-α, IL-4, IL-6, AGP, and ADA activities were significantly higher in infected animals from day 7 PI (P<0.05). In conclusion, the circulatory levels of most systemic inflammatory markers, including pro-inflammatory cytokines (IFN-γ, TNF-α, IL-4, IL-6), AGP, and ADA increased significantly starting from day 3 to day 7 PI in caprine coccidiosis.

Changing Patterns of Acute Phase Proteins and Inflammatory Mediators in Experimental Caprine Coccidiosis

This experiment was conducted to assess the changing patterns and relative values of acute phase proteins and inflammatory cytokines in experimental caprine coccidiosis. Eighteen newborn kids were allocated to 3 equal groups. Two groups, A and B, were inoculated with a single dose of 1x10(3) and 1x10(5) sporulated oocysts of Eimeria arloingi, respectively. The third group, C, received distilled water as the control. Blood samples were collected from the jugular vein of each kid in both groups before inoculation and at days 7, 14, 21, 28, 35, and 42 post-inoculation (PI), and the levels of haptoglobin (Hp), serum amyloid A (SAA), TNF-alpha, and IFN-gamma were measured. For histopathological examinations, 2 kids were selected from each group, euthanized, and necropsied on day 42 PI. Mean Hp concentrations in groups A and B (0.34 and 0.68 g/L) at day 7 PI were 3.2 and 6.3 times higher than the levels before inoculation. The mean SAA concentrations in groups A and B (25.6 and 83.5 microg/ml) at day 7 PI were 4.2 and 13.7 times higher than the levels before inoculation. The magnitude and duration of the Hp and SAA responses correlated well with the inoculation doses and the severity of the clinical signs and diarrhea in kids. These results were consistent with the histopathological features, which showed advanced widespread lesions in group B. In both groups, significant correlations were observed for TNF-alpha and IFN-gamma with SAA and Hp, respectively. In conclusion, Hp and SAA can be useful non-specific diagnostic indicators in caprine coccidiosis.