Comparison of hematological blood parameters when studying chronic toxicity of Protigen feed additive

Urea as a feed additive can be used in ruminant diets to provide degradable protein in the rumen. Its economic value justifies interest in using this additive as a partial replacement for plant protein sources. Urea processing in the rumen has some peculiarities: rapid hydrolysis to ammonia exceeding the rate of carbohydrate fermentation in the rumen and, consequently, a decrease in the efficiency of microbial crude protein synthesis, and an increase in the risk of ammonia toxicity as the result of increase in the concentration of ammonia in the blood. Therefore, there is a need for preliminary processing of this feed additive, for example using coating technology to develop sustained release urea products that could control urea degradation and ammonia release into the rumen. Protigen feed additive is an innovative ingredient that provides slow release of non-protein nitrogen in the rumen. Its large-­scale implementation in animal diets requires additional research on biological effects of using this feed additive. Thus, the purpose of our research was to study the effect of Protigen feed additive on some hematological parameters of rats. The object of the research was 50 outbred rats (♀) weighing 190—210 grams. Based on the results of previous studies, the first experimental group received the feed additive at a dose of 1/5 of the maximum tolerated (1000 mg/kg body weight), the second — 1/10 of the maximum tolerated (500 mg/kg body weight), the third (control) group did not receive the feed additive. The values of hematological parameters in laboratory animals were recorded after 90 days of daily feeding of the feed additive (91 days of the experiment) and 10 days after discontinuation of the drug (101 days of the experiment). When studying biological effects of using Protigen feed additive on hematological parameters of rats, no statistically significant differences were found compared to the control group.