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We examined the effect of amphotericin B (AmB) on the following enzymatic markers: aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), and on non-enzymatic markers: glucose, triglycerides, and proteins in the haemolymph of a model organism, Apis mellifera. AmB is an antifungal antibiotic. Despite its toxicity, it is used to treat disease conditions. The haemolymph of honey bees is considered as an analogue of human blood, and changes in marker values indicate pathological states, both in humans and honey bees. Three groups of caged bees were fed sugar syrup (the control group). The syrup was supplemented with AmB at concentrations of 0.25 mg/ml (AmB-25) and 0.50 mg/ml (AmB-50). The authors observed that the biochemical markers were age-related in the control group. Decreased values of the enzymatic markers in the AmB-treated groups confirm that AmB has a negative effect on the organism. The higher the dose of the antibiotic, the greater the increase in the concentration of the non-enzymatic markers. Our research shows that honey bees are an important model for studying the effects of AmB.
:Effect of mating nucs spacing and subspecies of honey bee (Apis mellifera) on the drifting of queens returning from mating flights. The loss of honeybee queens during mating flights increases the cost of their production. The aim of the study was to examine if the spacing of nucs influences the drifting of queen honey bees which return from mating flights. The study also compared the drifting of Carniolan (A. m. carnica) and Italian (A. m. ligustica) queens. We examined the total of 89 queens which were placed in mating nucs together with about 1000 workers. Some of the mating nucs were arranged in rows spaced 30 centimetres apart, without any landmarks, and other nucs were spaced a few meters apart, next to trees or bushes. Each group of nucs included Carniolan and Italian queens. The results show that significantly more queens failed to return from mating flights to nucs placed in rows without any landmarks (51%) than from those placed next to trees or bushes (7%). The study also showed that there is no significant differences between level of drifting of Carniolan and Italian queens.
The aim of research was the assessent of the hygienic behaviour of worker bees. The hygienic behaviour was assessed by means of two test types: the traditional needle test and a test proposed by the authors that consisted in measuring the removal rate of cardboard pieces. The experiments were conducted over three seasons and comprised a total number of 60 colonies. It was proved that the cardboard removal test may replace the needle test in the selection process of bees resistant to brood diseases, but primarily in those bees that have a good expression of hygienic behaviour. The best test results are to be expected in tests which last for 24 hours.
The aim of this study was to learn the strength of floral fidelity of honeybee colonies and to find what is the relationship between this trait and the amount of collected pollen. The observations were carried out in 2003 and 2004 on 10 honeybee colonies. The pollen was gathered from pollen loads collected using a pollen trap with a 5-mm screen mesh. A scanning electron microscope was used to view pollen grains in order to determine the number of plant species visited by the bees. The mean values of floral fidelity estimated individually for each experimental colony ranged from 40.1 to 75.7% in the first year, and from 45.1 to 67.3% in the second year of the studies. Correlation between floral fidelity and the quantity of collected pollen was observed in 60% of the colonies in the first year and in 70% in the second year. Recurrence of this relationship over the period of two years was found in only 30% of the studied honeybee colonies.
The paper contains the description of mass poisoning of honey bees and the method used to determine dichlorodiphenyltrichloroethane, methoxychlor, and lindane in the insects. The ultrasound-aided extraction of pesticides from dead bees was conducted using dichloromethane and the analysis of the extracts was conducted using gas chromatography-mass spectrometry. The whole procedure was vatidated.
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