The conducted research was aimed at determination of the impact produced by feeding protein and mineral feed additive produced out of the primary processing aquatic organisms wastes: sea mussels, red algae as well as of the sea water upon the productivity and non-specific resistance of broiler chickens raised in conditions of the normative and non-normative characteristics of the broiler house microclimate. The feed additive was applied to 20–42 day broiler chickens of “Ross 308” cross. The studied broilers were clinically healthy. Throughout the entire experiment, a series of the sanitary and hygienic microclimate parameters were determined, such as temperature, humidity, rate of changes as well as bacterial contamination of air, content of ammonia and carbon dioxide in air, and illumination of the broiler house. The house temperature was measured every day with the aid of a common spirit-in glass thermometer. Air humidity was established with the aid of an August psychrometer, air draft speed, harmful gas concentrations and illumination indicators were measured in compliance with the generally accepted methods. Bacterial contamination was determined with the use of the method of microorganism precipitation on a solid breeding ground placed in Petri dishes followed by a count of the bacterial colonies per 1 m3. The blood analysis included determination of haemoglobin, erythrocytes and leukocytes. In the blood serum, the lysozyme activity (LABS) and bactericidal activity (BABS) were determined. It was established that enriching the basic ration with the protein and mineral additive in quantity of 7 % in addition to the feed mass under conditions of the normative microclimate produced a positive effect on the growth intensity, livability and non-specific resistance indices of the broiler chickens. Thus, the live weight of broilers was reliably greater by 4.7 % and the livability equalled 100 %. The haemoglobin content was reliably greater by 7.6 %, erythrocytes – by 11.5 %, BABS – by 34.5 % and LABS – by 35.9 % as compared with the control group of broiler chickens. At the same time, when the studied feed additive was fed to broiler chickens kept in the microclimate conditions that did not meet the normative requirements, the reliable difference to the control indices was not established. Hence, the research results have proved that application of the protein and mineral feed additive is effective under the optimal microclimate conditions. High figures of livability and growth intensity of broiler chickens are based on a high resistance which is being formed provided the optimal microclimate and application of feed additives have been provided.