No abstract

Varroa destructor is the most important honey bee parasite. There are various methods used in the control of this mite, but none of them meets all requested criteria, to be safe, effective and easy to apply. The objective of this study was to evaluate the varroacidal efficacy of newly created plant-derived formulation Argus Ras (mixture of extracts of Sophora flavescens, Ginkgo biloba, Gleditsia chinensis and Teucrium chamaedrys) in a field trial. The investigation was conducted on 240 Apis mellifera colonies equalized in respect of brood amount, adult bee population and food reserves. Efficiency was evaluated by applying Argus Ras consecutively with two other acaricides, amitraz and oxalic acid. Average acaricidal efficacy of Argus Ras was 80.89%, being higher of other previously tested essential oils. Besides, it showed a potential in knocking down the mites resistant to other acaricides. It should not be neglected that Argus Ras requires a smaller number of treatments and financial investments than other formulations used for the control of Varroa mites.

Commercially and traditionally managed bees were compared for oxidative stress (superoxide dismutase (SOD), catalase (CAT), glutathione S-transferase (GST) and malondialdehyde (MDA)), the prevalence of parasites (Lotmaria passim, Crithidia mellificae and Nosema ceranae/apis) and social immunity (glucose oxidase gene expression). The research was conducted on Pester plateau (Serbia—the Balkan Peninsula), on seemingly healthy colonies. Significant differences in CAT, GST and SOD activities (p < 0.01), and MDA concentrations (p < 0.002) were detected between commercial and traditional colonies. In the former, the prevalence of both L. passim and N. ceranae was significantly (p < 0.05 and p < 0.01, respectively) higher. For the first time, L. passim was detected in honey bee brood. In commercial colonies, the prevalence of L. passim was significantly (p < 0.01) lower in brood than in adult bees, whilst in traditionally kept colonies the prevalence in adult bees and brood did not differ significantly. In commercially kept colonies, the GOX gene expression level was significantly (p < 0.01) higher, which probably results from their increased need to strengthen their social immunity. Commercially kept colonies were under higher oxidative stress, had higher parasite burdens and higher GOX gene transcript levels. It may be assumed that anthropogenic influence contributed to these differences, but further investigations are necessary to confirm that.

Yugoslavian Shepherd Dog - Sharplanina (YSD) is a livestock guard dog from the Western Balkans present in this region over a long time, but recognized by the Fédération Cynologique Internationale as a distinct breed as late as 1957. However, the information regarding the origin and the size of the breed’s foundation stock is still lacking. In order to contribute towards better understanding of the genetic make-up of the YSD and its foundation stock, we re-analyzed previously generated genetic profiles of 94 registered YSD dogs assessed with nine nuclear microsatellites. Studied individuals comprised 90 unrelated dogs and two pairs of full-sibs, sampled at four sampling sites: three dog shows and at a military training centre for dogs in Serbia. We supported earlier findings on high levels of genetic diversity in YSD (HE=0.728±0.027) and lack of inbreeding, and revealed substructure of the breed because we found two distinct gene pools in the Bayesian clustering analysis, indicated also by the excess of homozygotes (i.e., Wahlund effect) and outcomes of other analyses: linkage disequilibrium tests, Neighbour-Joining tree, principal coordinates and two-dimensional scaling analyses. The two gene pools were almost equally represented at each sampling site. One gene pool was composed of individuals with high genetic integrity, while the other gene pool was characterized with admixed ancestry, developed possibly via hybridization with native breeding stock outside the registry system, other breeds, such as the Caucasian Shepherd, and/or individuals admixed with wolves. Thus, we demonstrate rather complex and diverse ancestry implying a genetically heterogeneous foundation stock of the YSD.