<abstract xmlns="http://www.w3.org/1999/xhtml">

<sec id="j_jvetres-2021-000068_s_005">
<h3>Introduction</h3>
<p>The rearing of calves is a difficult period for farmers due to health problems to which the animals are prone this time. Since the use of antibiotics as growth promoters has been forbidden, various innovative feed additives have been tested in many countries around the world.</p></sec>
<sec id="j_jvetres-2021-000068_s_006">
<h3>Material and Methods</h3>
<p>In this study, experimental (E) calves were supplemented with a novel feed additive consisting of the pancreatic-like enzymes protease and lipase, a fat-coated mixture of organic fumaric, malic, citric and sorbic acids, sodium butyrate and silicon dioxide nanoparticles. Control (C) calves received feed without additive. During the supplementation, white blood cell (WBC) counts with leukocyte differentiation, percentages of B lymphocytes and T lymphocytes and their subpopulations, phagocytic activity and oxidative burst of circulating monocytes and granulocytes were examined. Body weight (b.w.) gains of the calves were also monitored.</p></sec>
<sec id="j_jvetres-2021-000068_s_007">
<h3>Results</h3>
<p>The WBC counts in the E and C calves were within the reference ranges throughout the study. In the analysis of the percentages of the lymphocyte subpopulations, phagocytic activity and oxidative burst, no statistically significant differences were reported between the E and C groups. However, higher average daily body weight gains were obtained for the E calves.</p></sec>
<sec id="j_jvetres-2021-000068_s_008">
<h3>Conclusion</h3>
<p>The study revealed that the examined feed additive did not modulate the immune response of the calves significantly. The tendency to higher daily average b.w. gains in the E calves than in the C calves suggests a beneficial effect of this feed additive.</p></sec>
</abstract>

Introduction
The rearing of calves is a difficult period for farmers due to health problems to which the animals are prone this time. Since the use of antibiotics as growth promoters has been forbidden, various innovative feed additives have been tested in many countries around the world.

Material and Methods
In this study, experimental (E) calves were supplemented with a novel feed additive consisting of the pancreatic-like enzymes protease and lipase, a fat-coated mixture of organic fumaric, malic, citric and sorbic acids, sodium butyrate and silicon dioxide nanoparticles. Control (C) calves received feed without additive. During the supplementation, white blood cell (WBC) counts with leukocyte differentiation, percentages of B lymphocytes and T lymphocytes and their subpopulations, phagocytic activity and oxidative burst of circulating monocytes and granulocytes were examined. Body weight (b.w.) gains of the calves were also monitored.

Results
The WBC counts in the E and C calves were within the reference ranges throughout the study. In the analysis of the percentages of the lymphocyte subpopulations, phagocytic activity and oxidative burst, no statistically significant differences were reported between the E and C groups. However, higher average daily body weight gains were obtained for the E calves.

Conclusion
The study revealed that the examined feed additive did not modulate the immune response of the calves significantly. The tendency to higher daily average b.w. gains in the E calves than in the C calves suggests a beneficial effect of this feed additive.

A pilot study on the effect of a novel feed additive containing exogenous enzymes, acidifiers, sodium butyrate and silicon dioxide nanoparticles on selected cellular immune indices and body weight gains of calves

Journal of Veterinary Research

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Introduction
The rearing of calves is a difficult period for farmers due to health problems to which the animals are prone this time. Since the use of...

A pilot study on the effect of a novel feed additive containing exogenous enzymes, acidifiers, sodium butyrate and silicon dioxide nanoparticles on selected cellular immune indices and body weight gains of calves

Article Category: Review article

Published Online: Dec 20, 2021

Page range: 497 - 504

Received: Jun 28, 2021

Accepted: Nov 30, 2021

DOI: https://doi.org/10.2478/jvetres-2021-000068

Keywords
calves, feed additive, immune response, average daily body weight gains

© 2021 E. Szacawa et al. published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

A pilot study on the effect of a novel feed additive containing exogenous enzymes, acidifiers, sodium butyrate and silicon dioxide nanoparticles on selected cellular immune indices and body weight gains of calves

Article Category: Review article

Published Online: Dec 20, 2021

Page range: 497 - 504

Received: Jun 28, 2021

Accepted: Nov 30, 2021

DOI: https://doi.org/10.2478/jvetres-2021-000068

Keywordscalves, feed additive, immune response, average daily body weight gains

© 2021 E. Szacawa et al. published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Keywords
calves, feed additive, immune response, average daily body weight gains