John M. Hranitz

Ethanol increases HSP70 concentrations in honeybee (Apis mellifera L.) brain tissue.

Previous research on the honeybee ethanol model established how acute ethanol exposure altered function at different levels of organization: behavior and learning, ecology, and physiology. The purpose of this study was to evaluate whether ethanol doses that affect honeybee behavior also induce a significant stress response, measured by heat shock protein 70 (HSP70) concentrations, in honeybee brain tissues. Experiment 1 examined how pretreatment handling influenced brain HSP70 concentrations in three pretreatment groups of bees; immediately after being collected, after being harnessed and fed, and after 22-24h in a harness. HSP70 concentrations did not differ among pretreatment groups within replicates, although we observed significantly different HSP70 concentrations between the two replicates. Experiment 2 investigated the relationship between ethanol dose and brain HSP70 concentrations. Bees were placed in seven experimental groups, the three pretreatment groups as in Experiment 1 and four ethanol-fed groups. Bees in ethanol treatments were fed 1.5M sucrose (control) and 1.5M sucrose-ethanol solutions containing 2.5, 5, and 10% ethanol, allowed to sit for 4h, and dissected brains were assayed for HSP70. We observed ethanol-induced increases in honeybee brain HSP70 concentrations from the control group through the 5% ethanol group. Only bees in the 5% ethanol group had HSP70 concentrations significantly higher than the control group. The inverted U-shaped ethanol dose-HSP70 concentration response curve indicated that ingestion of 2.5% ethanol and 5% ethanol stimulated the stress response, whereas ingestion of 10% ethanol inhibited the stress response. Doses that show maximum HSP70 concentration (5% ethanol) or HSP70 inhibition (10% ethanol) correspond to those (> or =5% ethanol) that also impaired honeybees in previous studies. We conclude that acute ethanol intoxication by solutions containing > or =5% ethanol causes significant ethanol-induced stress in brain tissue that impairs honeybee behavior and associative learning.

Determination of Acute Oral Toxicity of Flumethrin in Honey Bees

ABSTBACT Flumethrin is one of many pesticides used for the control and treatment of varroatosis in honey bees and for the control of mosquitoes and ticks in the environment. For the control of varroatosis, flumethrin is applied to hives formulated as a plastic strip for several weeks. During this time, honey bees are treated topically with flumethrin, and hive products may accumulate the pesticide. Honey bees may indirectly ingest flumethrin through hygienic behaviors during the application period and receive low doses of flumethrin through comb wax remodeling after the application period. The goal of our study was to determine the acute oral toxicity of flumethrin and observe the acute effects on motor coordination in honey bees (Apis mellifera anatoliaca). Six doses (between 0.125 and 4.000 µg per bee) in a geometric series were studied. The acute oral LD50 of flumethrin was determined to be 0.527 and 0.178 µg per bee (n = 210, 95% CI) for 24 and 48 h, respectively. Orally administered flumethrin is highly toxic to honey bees. Oral flumethrin disrupted the motor coordination of honey bees. Honey bees that ingested flumethrin exhibited convulsions in the antennae, legs, and wings at low doses. At higher doses, partial and total paralysis in the antennae, legs, wings, proboscises, bodies, and twitches in the antennae and legs were observed.

Effective Population Size and Genetic Structure of a Population of Collared Lizards, Crotaphytus collaris, in Central Oklahoma

Abstract We estimated effective population size (Ne) in Collared Lizards (Crotaphytus collaris) via ecological and genetic methods. The ecological method employed life-history data from three years of mark-recapture studies and yielded an Ne estimate of 46. The genetic method used allele frequency changes over one generation and yielded an Ne estimate of 33 (95% CI; 10, 76). Dispersal, measured as displacement of territories or home ranges in one season, was low (average = 30.5 m) and did not differ among life-history stages or between sexes. Gene flow among habitat patches at our study site appeared sufficient to prevent genetic divergence or subdivision within the population. The observed small effective population size supports models of evolution in C. collaris, wherein stochastic processes could influence strongly the evolution of this species. Similarities in estimates of Ne suggest that the effective population size of this population does not differ from the size of a recent founder population and, moreover, that genetic and ecological methods yield compatible results when assumptions of the two methods are satisfied by the study design.

Feature-positive and feature-negative learning in honey bees

SUMMARY Honey bees (Apis mellifera anatolica) were subjected to sequential trials where they were given the choice between a feature-positive and a feature-negative feeding plate. The ‘feature’ being manipulated is the presence of a single blue circle among three circles marking the location of a small sucrose reward. That is, a ‘feature-negative’ target had three white circles, while a ‘feature-positive’ target had two white circles and one blue one. Two experiments were performed. In both experiments, each bee was tested under two different reward scenarios (treatments). In the first experiment, during the feature-positive treatment bees received 4 μl of 2 mol l−1 sucrose when choosing the feature-positive plate, but received 4 μl of saturated NaCl solution (saltwater) when choosing the feature-negative plate. During the feature-negative treatment, bees were rewarded when visiting the feature-negative plate, while visitation to the feature-positive plate only offered bees the saltwater. The second experiment was a repeat of the first except that pure water was offered instead of saltwater in the non-rewarding feeding plate. As an experimental control, a set of bees was offered sequential trials where both the feature-positive and feature-negative plates offered the sucrose reward. Bee feeding plate choice differed between the feature-positive and feature-negative treatments in both experiments. Bees favored the feeding plate type with the sucrose reward in each treatment, and never consumed the saltwater or pure water when encountered in either treatment. Further, behavior of bees during both the feature-positive and feature-negative treatments differed from that of control bees. However, neither feature-positive nor feature-negative learning reached high levels of success. Further, a feature-positive effect was seen when pure water was offered; bees learned to solve the feature-positive problem more rapidly. When we tested bees using simply the choice of blue versus white targets, where one color held the sucrose reward and the other the saltwater, a bees fidelity to the color offering the sucrose reward quickly reached very high levels.

Stress responses of honey bees to organic acid and essential oil treatments against varroa mites

Natural medicines such as formic acid, oxalic acid, thymol and menthol have recently been used as alternative treatments against the honey bee parasitic mite varroa. The aim of this study was to observe and examine their impact on Heat Shock Proteins (HSP 70) in the brain tissues of bees. For this purpose, seven different treatment groups were created using various concentrations and administrations of formic and oxalic acid and thymol-menthol mixtures, including positive (untreated) and negative controls. The results showed that in the groups exposed to the varroa treatments, HSP 70 results were lower than those of the non-treated groups. HSP 70 results were lowest in the thymol-menthol mixture exposed group among the treated groups. We conclude that it would be more beneficial to prefer natural medicines against varroa, which lead to lower HSP 70 results which are the molecular determinants of stress.