The effect of Fenbion, an anthelmintic, on blood in heifers]

The complex effects of the anthelminthic Fenbion (prepared on the basis of fenbendazole, Bioveta Nitra) were investigated; its effects on the blood picture were studied in heifers with the liveweight of 400 kg, until the sixth day after its single application at doses of 15 and 30 mg per kg liveweight. The haemoglobin (Hb) content decreased in keeping with the physiological standard. The haematocrit (Hk) value decreased below the reference standard from 0.31 and 0.32 l per l on days five and six to 0.28-0.29 l per l. The total leucocyte counts increased from 8.60-9.64 G per l to 10.54-11.0 G per 1. This means that on the first days after administration Fenbion has negative effects on erythropoiesis, and as a stressor it evokes defense reactions of the organism. Differential blood counting: leucocyte counts increased to 0.71-0.73 arb. u. on days three to four. The increase in lymphocyte counts in the blood after Fenbion administration is likely to be related to the cellular immunobiological defense reaction of the organism. The counts of segmented leucocytes decreased, the counts of eosinophils increased irregularly, those of basophils and monocytes were highly variable, and the counts of monocytes increased irregularly in a large span, or they decreased.