Effectiveness of Oxalis bee and Ecostop for prophylaxis and control of varroosis in honey bees (Apis mellifera L.)

I. Zhelyazkova*, S. Lazarov
Department of Animal husbandry – Non-ruminants and other animals, Faculty of Agriculture, Trakia University, 6000 Stara Zagora, Bulgaria

(Manuscript received 24 August 2018; accepted for publication 26 October 2018)

Abstract. The objective of the present study is to determine the effectiveness of Ecostop (plates) and Oxalis Bee – plant-based products for the prevention and control of varroosis in bees (Apis mellifera L.).The study was conducted at the end of the 2017 Beekeeping Season of the Beekeeping Experimental Training Center at the Faculty of Agriculture, Trakia University, Stara Zagora. Two products were used: Ecostop containing peppermint oil (2 ml/plate) and timol (5 g/plate), and Oxalis Bee – zootechnical feed additive for bees, including plant extracts, organic acids and invert solution from bio-sugar. The dosing of the products is in accordance with the instructions of the producers Primavet-Sofia Ltd., Bulgaria and the company Vechni pcheli Ltd., Bulgaria. The development and extensinvasion of bee colonies at the beginning and the end of the study and the effectiveness of the applied products were determined. It has been established that the development of bee colonies is normal for the end of the beekeeping season. The comparative analysis of the acaricidal effect of the test products against Varroa destructor shows 98.55±0.30% for Ecostop and 78.15±8.76% for Oxalis Bee. The reported difference in efficacy of both preparations is reliable at p≤0.05.

Honey bees and their products as indicators of environmental pollution: A review

D. Salkova*, M. Panayotova-Pencheva

Department of Experimental Parasitology, Institute of Experimental Morphology, Pathology and Anthropology with Museum, Bulgarian Academy of Sciences, Acad. G. Bonchev 25, 1113 Sofia, Bulgaria

(Manuscript received 18 January 2016; accepted for publication 8 August 2016)

Abstract. In the present work a literature review of the experiments that explore the use of honey bees and their products as bioindicator of environmental pollution is presented. The greatest number of studies has been carried out on contaminations with heavy metals, followed by pesticides, radionuclides and other substances. Pb, Cd and Zn have been the most looked for metals. Zn and Cd have been mainly deposited on the surface of the bee body while Ni, Cd, Pb and Co have been released with the excrements most often. In all cases of pesticide implementation certain amounts of them have been always accumulated in the bees and their products. According to the researchers, pollutants accumulate in the bees and their products at different extents. Heavy metals and pesticides have been established in the bodies of honey bees in larger quantities in comparison to honey. Most of the authors reported that bee honey is a suitable tool for monitoring pollution with heavy metals and pesticides but the opposite assertions have been also expressed. A suggestion for the presence of a bio-barrier function of the bee organism against contaminators has been forwarded. It has been established that pollen is the most suitable indicator for radioactive pollution. As a whole, the present review shows that bees and their products are suitable models for bio-monitoring of the environmental pollution of different nature.


Stimulating feeding and development of hypopharyngeal and thoracic glands of honeybees (Apis mellifera L.)

R. Shumkova1, I. Zhelyazkova2*

1Experimental Station of Stockbreeding and Agriculture, 4700 Smolyan, Bulgaria
2Department of Animal Science, Faculty of Agriculture, Trakia University, 6000 Stara Zagora, Bulgaria

Abstract. The effect of some stimulating products on the development of the hypopharyngeal (HPhG) and the thoracic glands (ThG) of worker bees was studied. The investigation was conducted in the spring period of 2012 at the Experimental apiary of the Experimental Station of Stockbreeding and Agriculture (ESSA) in Smolyan, Bulgaria. Products ‘Vita Feed Gold (VFG)’, ‘Apidas’, ‘Oligofosi’ and ‘Anolyte-7’ were used for stimulating feeding of bee colonies. Five groups, each of five bee colonies were formed. Samples from bees for investigation of HPhG and ThG were taken after finishing the feeding. The state of glands was determined in non-flying 5-10-day worker bees (30 from each colony). The 4-point scale of Hess (in rates, Maurizio, 1954) is used for establishing the degree of development of hypopharyngeal glands. The diameter of 10 glandular blebs of HPhG of each bee is additionally measured. Height and diameter of 10 glandular tubes are measured and their volume is calculated for determining the degree of development of the thoracic glands of each bee. Binocular loupe MBS-1 with ocular micrometer is used for measurement. It is established that with the highest degree of development are HPhG of worker bees (3.90±0.06 rates and 0.102±0.0017 mm diameter of glandular blebs), receiving with their food ‘VFG’ – respectively, 1.06 and 1.27 times more than bees from the control group. From the studied stimulating products, the preparation ‘Apidas’ (includes plant extracts) is also with well expressed positive effect on the development of HPhG of bees. The obtained values of the studied parameter in bees receiving ‘Anolyte-7’ (electrochemically activated water solution) and those of the control group are commensurable. Positive influence of preparations ‘Apidas’ and ‘VFG’ on the volume of the measured glandular tubes from the thoracic glands of worker bees is determined. The reported values for volume of glandular tubes in bees receiving with their food the indicated stimulating preparations (0.005 and 0.004 mm3) are 2.0 – 2.5 higher than the studied parameter in bees from the control group (0.002 mm3) and those fed with ‘Anolyte-7’ (0.002 mm3) and ‘Oligofosi’ (0.001 mm3).


Study of bee honey by spectral analysis in the near infrared spectrum

I. Zhelyazkova, S. Atanasova , K. Elencheva – Karaneycheva
Abstract. The objective of the present study is to examine samples of bee honey of different origin and create models for their classification through spectral analysis in the near infrared spectrum. Representative samples unifloral (sunflower, acacia, lime and coriander), multifloral and honeydew honey are used. The origin of the above honey samples has been determined in advance by pollen analysis. The spectral measurement (NIR spectroscopy) of each sample was done non-destructively, by measuring the diffuse reflection of the honey samples using the spectral device NIRQuest 512 within the range 900–1700 nm. The spectral differences between the different types of bee honey have been studied. For classification of the samples based on their spectra the SIMCA method (Soft Independent Modeling of Class Analogy) was used. Models for distinguishing different types of bee honey – unifloral, multifloral and honeydew – have been obtained. The results show 100% accuracy of classification of the samples from the three groups based on the received spectral information. The most compact is the group of honeydew honey.


Effect of the feeding of products stimulating the development of bee colonies

R. Shumkova, I. Zhelyazkova
Abstract. The study was conducted in the spring and autumn of 2011 at the Experimental apiary of the Agricultural and Stockbreeding Experimental Station (ASES), Smolyan and at the private apiary of Mitev’s bee farm, Smolyan. For stimulating feeding of the bee colonies are used products “Vita Feed Gold”, “Ecophil-P”, “Apidas”, “Oligofosi” and “Anolyte -7”. To each family are provided a total of 5 l of sugar syrup for the individual periods (spring and autumn), 500 ml are given in the feeding troughs of hives at intervals of 2–3 days. The measurements of the studied indications are done with a measuring frame (size 5 x 5 squares cm) in 12 days. Some parameters are: strength of bee colonies (kg); volume of sealed worker brood and egg productivity of queen bees (number of cells). During the spring test a clear positive impact of “Vita Feed Gold” and “Apidas” is found. The influence of the other detergents for stimulating individual apiaries is comparable to that of the control feeding only with sugar solution. The results obtained during the autumn period of the study show that the specified values for strength of bee colonies fed with “Apidas” and “Anolyte -7” are 125.26% and 131.58% higher than this indicator in the control group. For the amount of sealed worker brood were recorded higher values for the bee colonies that received “Anolyte -7” (125.47%), “Apidas” (110.56%) and “Vita Feed Gold” (111,3% ) compared to the control. The results show that “Ecophil-P” and “Oligofosi” do not have clear stimulating effect on the development of colonies in both periods of the study.


Research on the stimulating effect of Tribulus terrestris on the oviparous activity of the queen bees

I. Hristakov

Abstract. All major processes in the bee colony are closely related to nectariferous vegetation in the area. Oviparous activity of queen bees is directly dependent on the flow of nectar and pollen in the bee colony. When it rises it leads to increase of the oviparous activity of queens, and thus increases the power of the colony. Stimulating feeding with sugar syrup in the absence of pollen flow has little effect on the laying activity of the queens, as the syrup with biologically active substances which are necessary for bees and queens. This paper presents a research on the addition of extract of Tribulus terrestris L. as invert sugar syrup, by which we import some of the biologically active substances needed by bees and bee stimulating oviparous activity of the queen bees.


Content of heavy metals and metalloids in bees and bee products from areas with different degree of anthropogenic impact

I. Zhelyazkova, S. Atanasova, V. Barakova, G. Mihaylova

Abstract. Sample taking was carried out in the active bee season of 2010 (June – July) in order to make a comparative analysis of the content of some heavy metals and metalloids (copper Cu, zinc Zn, lead Pb, cadmium Cd, nickel Ni, cobalt Co, manganese Mn, iron Fe) in the body of bees (Apis mellifera L.), fecal mass, bee products (honey, pollen, wax) and sunflower flowers in areas with different degree of anthropogenic impact. The study includes two settlements in Stara Zagora region: the town of Gurkovo – an area with low level of anthropogenic impact; the village of Bratya Kunchevi – an area with established anthropogenic impact (working stone quarry on the territory of the village). Accumulation of the studied heavy metals and metalloids in the bee fecal mess is observed and high level of accumulation in excrements is exhibited by lead (1:2,3 – 1:4,0), cadmium (1:1,6 – 1:1,9), nickel (1:4,2 – 1:4,3), cobalt (1:1,6 -1:2,0). The biobarrier function of the bee organism is proved as a result of which heavy and toxic metals such as lead and cadmium are efficiently excreted by the organism through the fecal mass. It is established that Fe content is of higher values in the bee body, pollen and wax in the station village of Bratya Kunchevi (compared to the samples in the town of Gurkovo). A possible reason for the reported high quantity of iron in the analysed samples of the village of Bratya Kunchevi could be the working stone quarry on the territory of the village operating a deposition of andesite tuffs (calcium-magnesium-iron silicates). Unsatisfactory indicator characteristics of bee honey for environmental quality have been established in areas with different degree of anthropogenic impact compared to bee organism and pollen.