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The effects of acute sublethal doses of coumaphos, an acaricide used against Varroa destructor infestation in beekeeping, on the locomotor activities of four native honeybee subspecies of Türkiye including two ecotypes (Carniolan honeybee -A. m. carnica, Syrian honeybee -A. m. syriaca, Caucasian honeybee- A. m. caucasica, and Muğla and Yığılca ecotypes of Anatolian honeybee A. m. anatoliaca) were investigated using an individual locomotor activity monitoring system. Analysis of locomotor activity data in the first 12-h, last 12-h, and 24-h time periods showed that bees from caucasica and carnica subspecies were not affected by coumaphos at all three acute doses (1, 2, and 5 μg coumaphos in 10 μl sucrose syrup for each bee). In contrast, bees from A. m. syriaca subspecies showed significantly elevated locomotor activity levels at 2 and 5 μg coumaphos doses within the first 12 h. Bees from both Muğla and Yığılca ecotypes of anatoliaca subspecies also showed elevated locomotor activity levels at 5 μg coumaphos dose but the magnitude of increase was lower in these ecotypes compared to that seen in syriaca subspecies in the first 12-h period. In general, increasing doses of coumaphos resulted in increased locomotor activity (locomotor activity), with differences in sensitivity across honeybee populations. Possible mechanisms underlying this variance and suggestions for further studies are discussed. [ABSTRACT FROM AUTHOR]

Survival of European honey bee (Apis mellifera) colonies has been threatened over the past few decades as Varroa destructor has become a growing concern on a near-global scale. Prominent treatment methods have included the synthetic acaricides amitraz, coumaphos, and tau-fluvalinate. Since widespread resistance to these compounds has been noted, this study sought to investigate V. destructor resistance in Virginia. V. destructor infestation levels in apiaries located in three geographic regions of Virginia were monitored throughout the 2018 field season. By autumn, all apiaries had mite populations above the recommended treatment threshold. The results of resistance screening with glass surface contact bioassays indicated no resistance to amitraz, coumaphos, or tau-fluvalinate. These results have implications in future control strategies and responsible use of these acaricides may offer an additional option to those battling these aggressive ectoparasites. [ABSTRACT FROM AUTHOR]

We studied the distribution of coumaphos in beeswax after a single application of CheckMite® to 15 bee colonies in the fall according to the manufacturer's instruction. Immediately after the treatment, residue levels were especially elevated in the wax that came into contact with the CheckMite® strips. During the following spring season, coumaphos levels ranged from 36 to 159 mg/kg in the wax of the brood frames next to the CheckMite® strips, and residue levels were about 10 times lower in the wax of frames that did not come into contact with the strips. Beeswax that was newly constructed 5 months after removing the treatment strips contained up to 7.3 mg/kg of coumaphos, and up to 0.5 and 2.3 mg/kg was detected in the honeycomb and capping wax, respectively. These results suggest that beeswax exposed to CheckMite® should not be recycled in order to prevent elevated concentrations of coumaphos in new foundations and hence to prevent honeybee larvae from being exposed to detrimental residue levels. [ABSTRACT FROM AUTHOR]

The present experiment was conducted to evaluate and compare the impact of Ageratum conyzoides plant extract (ACE) with routinely used synthetic acaricides i.e., amitraz and coumaphos on the oogenesis of engorged adult females of Rhipicephalus microplus tick. On the day of dropping from the host, panoistic ovary of R. microplus appeared white in colour, horseshoe shaped, hollow tubular organ with immature oocytes predominantly in dorsal groove. Different developmental stages of oocytes (I–V) proceed simultaneously and asynchronously. Oocytes showed gradual increase in size, deep brown colored with accumulation of eggs in oviduct during 24–72 hours of development.At LC 90 concentration a highly significant (p < 0.001) cessation of egg laying after exposure to amitraz and ACE while significant reduction (p < 0.01) of egg laying in coumaphos treated ticks was observed. Upon dissection of treated ticks, uterus and oviduct packed with eggs, which failed to pass out was observed. The histo-architectural alterations including presence of extensive vacuolation, alteration of oocyte morphology, deformation of chorion and disorganization of yolk granules were observed in the treated ovaries. Histochemically, low level of storage or synthesis of essential elements viz., proteins, polysaccharides and lipids in treated oocytes responsible for reduction of fertility and inhibition of progress of vitellogenesis was observed. [ABSTRACT FROM AUTHOR]

Residues of acaricide coumaphos were assessed in honey, bee brood, and beeswax during a 2-year field experiment. Honey, bee brood, and beeswax samples were collected before and after routine use of coumaphos in the treatment of bee colonies against varroosis in two consecutive years. Determination of coumaphos in honey and bee brood was based on RP-HPLC with UV detection after a liquid-liquid extraction with hexane or ethyl acetate. Coumaphos in beeswax was identified and quantified by GC/MS. Results indicate the undetectable presence of coumaphos in honey. In bee brood, coumaphos was observed after the treatment. In beeswax, the accumulation of coumaphos was determined not only in hives where it was used but also in hives nearby in which coumaphos was not used. Results indicate the accumulation of coumaphos in bee brood and beeswax. Due to the coumaphos accumulation this drug should be used only in strongly affected bee colonies. [ABSTRACT FROM AUTHOR]

Varroa destructor is currently one of the main threats for western apiculture. Today, synthetic acaricides (specifically coumaphos, amitraz, and tau-fluvalinate) are the most common methods to control Varroa infestations. These compounds, however, are frequently related to a wide range of side effects in the host, as well as a long half-life inside the hive matrices (wax and honey). The western honey bee, Apis mellifera, exhibits natural defense mechanisms against the mite such as grooming behavior, which is a sequence of bodily movements where the host scrapes its legs across its body surface to remove the mite. We tested the effects of synthetic acaricides on the performance of grooming behavior by adult honey bee workers. We found that acaricide exposure prior to grooming delayed grooming and reduced the overall duration of grooming behavior. Our data add to a list of other sublethal behavioral consequences of acaricides that may subvert a comprehensive approach to Varroa control in managed colonies. [ABSTRACT FROM AUTHOR]

Discriminating concentrations (DCs) of malathion, coumaphos, fenvalerate and fipronil were determined to monitor acaricide resistance in field conditions. The LC 99 values with 95% confidence interval for malathion, coumaphos, fenvalerate and fipronil were 5126.8 (5011.5–5240.7), 131.0 (120.4–142.5), 2257.5 (2198.1–2318.4) and 6.2 (5.87–6.55), respectively. The narrow confidence intervals in LC 50 and LC 99 of adult immersion test (AIT) and larval packet test (LPT) affirming the homogeneity of IVRI-I line. Variation in LPT based LC 50 and LC 99 values of malathion (55.9 ppm) and coumpahos (28.4 ppm) compared to those obtained in AIT indicating that larvae were more susceptible to these chemicals. The DCs for malathion, coumaphos, fenvalerate and fipronil against adults were determined as 10253.6, 262.0, 4515.0 and 12.4 ppm while against larvae the values were 111.8, 56.8, 4014.0 and 9.6 ppm, respectively. The working efficiency of DCs was successfully tested in field tick isolates. Establishment of country specific DCs of commonly used insecticides for monitoring of resistance in field ticks is emphasized for establishing tick control strategies. [ABSTRACT FROM AUTHOR]

Honey can be polluted due to environmental pollution and misuse of beekeeping practices. In the present study, photodegradation experiments of organophosphorus pesticides (coumaphos, methyl parathion and fenitrothion) in honey medium were conducted using Atlas Suntest simulator CPS+ as a sunlight producer. Photodegradation experiments were conducted under three different intensities as 250 W/m2, 500 W/m2 and 750 W/m2 to evaluate the impact of sunlight intensity on removal of OPs in honey medium. Significant decreases of three OPs’ concentrations were observed. Coumaphos showed the highest degradability, reaching a degradation percentage of 90 percent within 15 min. After 1 h irradiation, residual percentages of coumaphos were 6.62 percent for 250 W/m2, 3.48 percent for 500 W/m2 and 2.98 percent for 750 W/m2, respectively. Methyl parathion and fenitrothion also could be removed through photodegradation efficiently. After 1 h irradiation, the residual percentages of methyl parathion and fenitrothion under 750 W/m2 sunlight irradiation were 26.89 percent and 16.70 percent, respectively. Intensity of sunlight showed a positive impact on removal of OPs in honey medium. The higher intensity, the lower residual percentage. Photodegradation of three OPs fitted well with pseudo-first order kinetics. Half-lives calculated from pseudo-first order kinetics were 17.61 min (250 W/m2), 16.67 min (500 W/m2) and 17.58 min (750 W/m2) for coumaphos, 57.62 min (250 W/m2), 34.13 min (500 W/m2) and 31.69 min (750 W/m2) for methyl parathion and 144.70 min (250 W/m2), 95.47 min (500 W/m2) and 22.57 min (750 W/m2) for fenitrothion, respectively. Most of the three OPs could dissipate in a short time under sunlight irradiation. Photodegradation could be accepted as an appropriate method for the removal of OPs in honey medium. [ABSTRACT FROM AUTHOR]

Forty-eight male Balb/C mice, allocated to 4 equal groups, constituted the material of the study. The first group was maintained as the control group and was administered solely with a vehicle, which was used to dissolve coumaphos in the third and fourth groups. The second group was administered with 1.5ml/kg.bw/day (∼1400mg/kg.bw/day) of wheat germ oil. The third group received 5.5mg/kg.bw/day (1/10LD50oral) of coumaphos. Finally, the fourth group was given both coumaphos and wheat germ oil at the doses indicated above. In all groups, the compounds were given directly into the stomach using a gastric tube, and treatment was continued for a period of 45 days. At the end of the 45th day, the liver, lungs, kidneys, brain, heart and spleen were extirpated in all of the animals. Tissue homogenates prepared from the tissue specimens were analysed for malondialdehyde (MDA) levels and catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities. In conclusion, it was determined that coumaphos led to adverse alterations in the majority of the oxidative stress markers investigated. The administration of wheat germ oil alleviated the coumpahos-induced adverse effects detected in the tissues examined. [Copyright &y& Elsevier]