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A population genetic analysis based on sequences of the mitochondrial control region in 110 red foxes from five sampling localities in northern Serbia was carried out. The analysis yielded nine different haplotypes. Neither haplotype phylogeny nor their distribution was in accordance with the geographic location of the populations. In particular, the data failed to detect an unequivocal influence of the two big rivers, the Danube and the Tisza, separating the populations studied. Population differentiation was altogether low, without any relationship to the rivers as possible migration barriers. Although the possibility of foxes crossing the rivers over bridges or by swimming, thus keeping up gene flow, cannot be ruled out, it is most probable that the control region sequences are not sensitive enough to resolve small-scale population relationships but rather show patterns determined by stochastic processes such as genetic drift or lineage sorting.

This study was done to discover any beneficial effect of a medicinal mushroom Agaricus brasiliensis extract on the honey bee. Firstly, a laboratory experiment was conducted on 640 bees reared in 32 singleuse plastic rearing cups. A. brasiliensis extract proved safe in all doses tested (50, 100 and 150 mg/kg/ day) irrespective of feeding mode (sugar syrup or candy). Secondly, a three-year field experiment was conducted on 26 colonies treated with a single dose of A. brasiliensis extract (100 mg/kg/day) added to syrup. Each year the colonies were treated once in autumn and twice in spring. The treatments significantly increased colony strength parameters: brood rearing improvement and adult population growth were noticed more often than the increase in honey production and pollen reserves. These positive effects were mainly observed in April. In conclusion, A. brasiliensis extract is safe for the bees and helps maintaining strong colonies, especially in spring.

The aim of this research was to investigate whether or not sugar dusting can stimulate the grooming behaviour in Apis mellifera L. (Hymenoptera: Apidae), an important defensive mechanism against Varroa destructor Anderson & Trueman (Acari: Varroidae), and to assess the most effective dose and frequency of treatment. The criterion for evaluation of grooming potential was the percentage of damaged mites (PDM) among the total number collected on the bottom boards of the hives. In each sugar‐treated group PDM was significantly higher in comparison both with the negative control (no treatment) and with the values preceding the treatment. The results point to a stimulating effect of sugar on the grooming behaviour at all doses and frequencies tested. Treatment frequency influenced the stimulating effect of sugar: treatments at 3‐ and 7‐day intervals with 30 and 40 g resulted in significantly higher PDMs than the least frequent treatment (every 14 days); dusting with 20 g influenced PDM only when repeated at 3‐day intervals. Because treatments at 3‐day intervals are time‐consuming, those with 40 or 30 g repeated every 7 days may be recommended. In the positive control (hives treated with amitraz), average PDM was significantly lower than in the negative control and all sugar‐treated groups. Possible causes of the stimulating effect of sugar dusting on bee grooming behaviour are discussed.