In order to test various hive systems in growing and exploitation of bee colonies, and in order to estimate comparative
advantages and disadvantages, assessment of biological bee comfort, as well as economic efficiency of their
exploitation in small and medium beekeeping farms, was carried out an experiment on comparative study of
maintaining bee colonies in different types of hives: horizontal and vertical, both with Dadant frames. Two similar
batches of bee colonies were created. The first batch of 20 colonies was put in horizontal hives and second batch with
25 colonies– in vertical hives. The main sources of honey in the area were: Acacia, Linden tree and spontaneous flora.
In beekeeping season of 2011 have been studied main biological and morpho productive characters of bee colonies,
such as: colony strengthens, resistance to overwinter and diseases, queens prolificacy, brood viability, total quantity of
honey collected in nest after harvest. Appreciation of morpho productive characters was done according to our
methodology developed by the new zootechnic regulation according to bee colonies valuation, growing and
certification of genitor beekeeping materials, approved by decision of Government of Republic of Moldova no. 306 of
28.04.2011. It was found that the types of hives, where were housed the experimental bees, all other equal conditions of
maintenance and exploitation, have not had any impact on the biological process of bees overwinter. This is confirmed
by the fact that the average strengthens of bee colonies in both experimental groups, being equal at the beginning of
experiment (1,78 kg in the autumn of 2010, in entry of overwinter) remained same in spring of 2011 (1,49 kg out of the
winter). Therefore, overwinter resistance of bee colonies in both groups was also identical, averaging 83.1%. At the
same time, the hive types, tested in experiment, had a significant influence on reproduction process and development of
bee colonies in high beekeeping season. Thus, the queens prolificacy from 2nd batch with bee colonies located in
vertical hives during the season, was higher compared to the Ist batch, accommodated in vertical hives, with 60 eggs/24
hours, or with 3.5% (B > 0.95). A better prolificacy activity of queens in vertical hives can be explained, in our view,
by the fact that they have a better comfort of laying, compared with those from horizontal hives. We found that in
horizontal hives, queens prefer for laying the area near bee entrance and it is explained by the fact that this place is
better aired and ensure the brood with sufficient oxygen. In vertical hives queens laying is more uniform and it is
spread on more honeycombs. This is due to a better and uniform ventilation in entire hive, which gives enough oxygen
to brood. All this, has led to an active laying of queens from vertical hives, also to a bigger amount of capped brood
and as a result, essential increase of bee colony strengthens. At the beginning of first harvest (locust tree), bee colonies
placed in vertical hives reclaimed at a bigger rate than those placed in horizontal hives. Regarding bee colonies
strengthens, those from 2nd batch exceeded significant, at this stage, those from 1st batch, with 0.33 kg or 9,4% (B >
0,99). Bee colonies from vertical hives entered overwinter significantly more powerful than bees from horizontal hives,
which creates premises for a stronger development and better productivity in the next beekeeping season. Due to a
quicker development, bee colonies kept in vertical hives accumulated, during active season, a bigger quantity of honey
in the nest. Thus, the total quantity of honey accumulated in nest, bee families maintained in vertical hives have
significantly exceeded those from horizontal hives with 7.5 kg, or 19,1% (B > 0.999). Economic effect obtained at
exploitation of vertical hives only from honey production is 375 MD lei, or 23.8 euro per bee colony. Based on
obtained results were made following conclusions. 1. Vertical hives compared to horizontal hives, offer to bee colony
more comfortable biological conditions. 2. Maintenance of bee colonies in vertical hives ensures an increase of queens
laying -3.5% and of average annual strengthens of the bee colony – with 6.0%. 3. Use of vertical hives contributes to
increasing of honey production with 19.1%. 4. Bee colonies exploitation in vertical hives ensures economic efficiency
at least 23.8 euro per bee colony.