Abstract:
Introduction. Currently, various biologically active substances are used more often used
in the breeding of birds as feed additives, which show a growth stimulating effect, but
preferably of biological, not synthetic origin. Some of these substances with a stimulating
effect on the growth of chickens are represented by the biomass obtained from apathogenic strains of Streptomycetes. The products of microbial synthesis of Streptomycete are
used in the form of complex preparations, which supplement the feed ration of poult ry,
which leads to optimizing the metabolism, the immune system and increase the productivity. In addition to its nutritional value, it also has an antimicrobial and immunomodulatory activity, which promotes food digestion and inhibits the development of pathogenic
microflora within the chickens’ intestines. The aim of our research was to study the influence of biomass of Streptomycetes administered in food composition on the performance
indices of body weight of chickens as well as on some blood indices.
Material and methods. The investigations were conducted within the ILR “Avicola
Sărătenii-Vechi” v. Sărătenii Vechi, Telenești district. The biological material was one-dayold Adler's silver chickens. The research was performed on 150 chickens, divided into
three groups of chickens (one control and two experimental samples), which were randomly distributed in three groups of 50 chickens per each. The study was performed over
a period of 7 weeks. In order to establish the breeding performance for the chickens, identical maintenance conditions, as close as in poultry units, were created.
Results. The analysis of the obtained results revealed that the cumulative consumption
of feed during the investigation period was lower in experimental group II, where this
index constituted 1969 g, compared with 2034 g in the experimental group I and 2104.6
g in the control group. The dynamics of body weight was higher in the experimental group
of chickens, which received biomass of Streptomycetes, indicating that the chickens in experimental group II recorded a 5.1% increase in body weight compared to chickens from
the control group. The daily average also was higher in experimental group II, having
5.2% higher compared to the chickens from the control group. At the same time, the consumption of poultry feed was 9.3% lower compared to the chicks from the control group.
The analysis of blood indices showed a slight increase of the number of lymphocytes and
eosinophils from 4 to 9% in the experimental group II of chickens that received the biomass of Streptomycetes in their ration, which indicates an immunostimulatory action on
the chickens’ body.
Conclusions. The use of biomass of Streptomycetes in ration of experimental group of
chickens had a positive influence on body weight index, which demonstrated a 5.1% increase of body weight compared to the chicks from the control group. The biomass of
Streptomycetes stimulated an increase of the number of limbocytes and eosinophils in
chickens from the experimental group II, indicating an immunostimulatory effect.
