The effect of an enzyme additive in combination with zinc in an ultrafine form on the productive performance of broiler chickens

Poultry  farming  is  one of  the  most  important  and  promising  branches  of  animal husbandry. Given the increasing rate of industrial poultry farming, for the stable development of the industry and improving competitiveness  in  world  markets,  more  and more attention is paid to the search for safe alternative  agents  to  increase  productivity. The study examined the strategy of feeding substances of different nature as feed additives, in particular, enzyme complexes separately  (group  I  (0,05%;  endo-1,4-beta-xylanase - 4000 units/g, alpha-amylase - 400 units/g and subtilisin - 8000 units/g)) and in combination with ultradispersed zinc (group II  (3  mg/kg;  164±31,2  nm)).  It  was  found that  in  group  I  the  digestibility  ratios  of crude  protein  were  higher  by  6.03  % (P≤0.05), crude  fiber  by  3.68  %  (P≤0.05), nitrogen-free  extractive  substances  by  2.39 %  (P≤0.05) compared  to  control.  At  the same time, in group II, changes were recorded in crude protein and crude fiber - an increase  of  6.51%  (P≤0.01)  and  7.59% (P≤0.05), respectively.  At  42  days  of  age, the  live  weight  of  broiler  chickens  I  was 10.1% higher than control (P≤0.05), and in group II by 11.32% (P≤0.01). At the same time, the cost of feed per 1 kg of growth was minimal in group II, 16.79% lower than the control values. Thus, the maximum productive effect was observed with the introduction  of  a  complex  enzyme  supplement  in combination  with  zinc  in  ultradispersed form.