Seasonal differences in the intensity of acute phase response in dogs infected with Babesia canis

The highest number of acute Babesia canis cases in dogs is recorded over the February–May (Feb–May) period, which also represents the optimal climate conditions for tick activity in Belgrade, Serbia. A possibility that the acute phase response is more intense in dogs developing the disease in the Feb–May period compared with the response in other time periods of the year was tested. A total of 63 client-owned dogs with acute B. canis infection were enrolled and the routine hematology and biochemistry parameters—serum amyloid A (SAA), IgG against B. canis , level of parasitemia, ceruloplasmin (CER), paraoxonase-1 (PON-1), and fibrinogen—were measured. Acute phase indexes (API) were calculated as (SAA×CER)/(Iron×PON-1) and (SAA×CER)/(Albumin×Iron). Statistics included Kruskal-Wallis test and logistic regression analysis. The results showed that in the Feb–May period, the following parameters were lower: creatinine, albumin, iron, and level of parasitemia. Furthermore, increased API values were more probable in the Feb–May than in the other periods. Together, higher acute phase response intensity and presumptive hemodilution in the Feb–May period indicate a more acute course of B. canis infection than in other time periods of the year.