Natural Products as Mite Control Agents in Animals: A Review.

Mites have been a persistent infectious disease affecting both humans and animals since ancient times. In veterinary clinics, the primary approach for treating and managing mite infestations has long been the use of chemical acaricides. However, the widespread use of these chemicals has resulted in significant problems, including drug resistance, drug residues, and environmental pollution, limiting their effectiveness. To address these challenges, researchers have shifted their focus towards natural products that have shown promise both in the laboratory and real-world settings against mite infestations. Natural products have a wide variety of chemical structures and biological activities, including acaricidal properties. This article offers a comprehensive review of the acaricidal capabilities and mechanisms of action of natural products like plant extracts, natural compounds, algae, and microbial metabolites against common animal mites.

Plant-based supplement containing B-complex vitamins can improve bee health and increase colony performance.

It is common knowledge that nutritive stress resulting from decreased diversity and quality of food, pollution of food sources and beekeeping errors may lead to increased susceptibility of bees to pathogens and pesticides. The dearth of adequate food is frequently compensated with supplements. Thus, this research was aimed to study the effects of the plant-based supplement B + on colony strength (assessed according to open and sealed brood area, honey and pollen/bee bread reserves, and the number of adult bees). In addition, Nosema ceranae spores and viruses were quantified and the level of infestation with Varroa destructor assessed. The experiment was conducted in late summer and early spring. In colonies which were given B + in feed a significant increase (p < 0.05) in the parameters of colony strength were noticed in comparison to the control (colonies fed on sugar syrup). Moreover, it was proven that the bees from these colonies had significantly lower (p < 0.05) N. ceranae spore counts, and acute bee paralysis, deformed wing and sacbrood virus loads. Our results suggest that the addition of B + supplement to the colonies provide them with nutrients, contribute to their strengthening, might prevent nutritive stress and increase the success of bees in combating pathogens.

The Effect of Volatile Oil from Chinese Mugwort Leaf on Human Demodecid Mites In Vitro.

BACKGROUND: Human demodecid mites including Demodex folliculorum and Demodex brevis Akbulatova can cause acne, rosacea, epifolliculitis, blepharitis, seborrheic dermatitis, perioral dermatitis, acromastitis and such skin health problems. Artemisia (Composiate) are widely distributed in temperate regions in the northern hemisphere. It has been reported that 17 species of plants in Artemisia used to be mugwort in China. Mugwort volatile oil (MVO) has antibacterial and antiviral effects, can relieve cough and asthma, acts as an expectorant, choleretic and sedative, and promotes circulation and enhances immunity. PURPOSE: This research was to observe the effect of MVO on two types of human demodecid mites in vitro. METHODS: The MVO was obtained via the supercritical CO2 extraction method, and the human demodecid mites were acquired with cellophane tape. MVO had a distinct killing effect on two types of human demodecid mites, Demodex folliculorum and Demodex brevis. The body of the demodecid mites has a classical temporal process, which consists of excitement, contractions, death and transparency. The killing time was lengthened with decreasing concentration, thus showing an evident dependence on concentration. RESULTS: The experiment showed that 3.125% was the minimum effective concentration of MVO for killing D. brevis, and 6.25% was the minimum effective concentration for killing D. folliculorum; the killing effect of MVO on D. brevis was greater than on D. follilorum. CONCLUSION: This result suggests that mugwort, which acts as a traditional Chinese herbal medicine, has a noticeable killing effect on human demodecid mites.

Review of extralabel use of isoxazolines for treatment of demodicosis in dogs and cats.

Amitraz is presently the only FDA-approved treatment for demodicosis in dogs in the United States. Amitraz treatment involves a protracted course of administration and risks of severe adverse effects such as sedation, bradycardia, and respiratory depression, which are caused by activation of α2-adrenergic receptors. Other treatment options include macrocyclic lactones and lime sulfur, but these products have varied efficacy and high risks of adverse effects. Several recent studies have indicated that isoxazolines are capable of reducing Demodex mite counts in canine and feline patients with demodicosis by ≥ 99% in as little as 1 month with few adverse effects. This article reviews the status of isoxazolines in regard to labeled uses in dogs and cats in the United States, extralabel clinical use for treatment of demodicosis in these species, and safety of orally administered formulations of these drugs.

Diagnosis and treatment of demodicosis in dogs and cats: Clinical consensus guidelines of the World Association for Veterinary Dermatology.

BACKGROUND: Demodicosis is a common disease in small animal veterinary practice worldwide with a variety of diagnostic and therapeutic options. OBJECTIVES: To provide consensus recommendations on the diagnosis, prevention and treatment of demodicosis in dogs and cats. METHODS AND MATERIALS: The authors served as a Guideline Panel (GP) and reviewed the literature available before December 2018. The GP prepared a detailed literature review and made recommendations on selected topics. A draft of the document was presented at the North American Veterinary Dermatology Forum in Maui, HI, USA (May 2018) and at the European Veterinary Dermatology Congress in Dubrovnik, Croatia (September 2018) and was made available via the World Wide Web to the member organizations of the World Association for Veterinary Dermatology for a period of three months. Comments were solicited and responses were incorporated into the final document. CONCLUSIONS: In young dogs with generalized demodicosis, genetic and immunological factors seem to play a role in the pathogenesis and affected dogs should not be bred. In old dogs and cats, underlying immunosuppressive conditions contributing to demodicosis should be explored. Deep skin scrapings are the diagnostic gold standard for demodicosis, but trichograms and tape squeeze preparations may also be useful under certain circumstances. Amitraz, macrocyclic lactones and more recently isoxazolines have all demonstrated good efficacy in the treatment of canine demodicosis. Therapeutic selection should be guided by local drug legislation, drug availability and individual case parameters. Evidence for successful treatment of feline demodicosis is strongest for lime sulfur dips and amitraz baths.

Modulation of feed composition is able to make hens less attractive to the poultry red mite Dermanyssus gallinae.

The poultry red mite (PRM) is an obligatory haematophagous pest that causes substantial economic losses in poultry worldwide. The PRM does not live on the host but in the bird's environment and must find its host remotely. Hence, manipulating chicken odours is of interest. Several crude plant-originating volatile organic compounds (VOCs) have already been shown as repellent to Dermanyssus gallinae. We aimed to test whether these VOCs can interfere with PRM host-seeking behaviour by their oral administration to the poultry. The objectives were to determine (1) if hen odours are modified by supplemented feed ingestion and (2) if such treatment makes hens less attractive to the PRM. Chemical characterization by gas chromatography-mass spectrometry of the hen odour was conducted before and after the hens ingested the supplemented feed. The chromatograms obtained show that hen odour was substantially modified after the hens consumed it. Among the molecules recurrently detected from the supplemented hens, 26% were nearly absent in the unsupplemented hens. Behavioural choice tests to compare the effect of the modified and unmodified-host odours on the PRM show that some of the plant-originating emitted VOCs and the modified whole-hen odours were repellent to the PRM.

Acaricidal activity of plant-derived essential oil components against Psoroptes ovis in vitro and in vivo.

BACKGROUND: Treatment of Psoroptes ovis in cattle is limited to topical acaricides or systemic treatment with macrocyclic lactones. Treatment failure of macrocyclic lactones has been reported. The aim of this study was to evaluate a potential alternative treatment against P. ovis. METHODS: The acaricidal activity against P. ovis of four plant-derived essential oil components, i.e. geraniol, eugenol, 1,8-cineol and carvacrol, was assessed in vitro and in vivo. In vitro contact, fumigation and residual bioassays were performed. In addition, 12 Belgium Blue cattle were artificially infested and treated topically once a week for three successive weeks with carvacrol in Tween-80 (treatment group) or with Tween-80 alone (control). The efficacy of carvacrol was determined by the reduction in lesion size and mite counts. Six additional animals were topically treated with carvacrol to assess local adverse reactions. RESULTS: Three components showed a concentration-dependent acaricidal activity in a contact assay, with LC50 of 0.56, 0.38 and 0.26% at 24 h for geraniol, eugenol, and carvacrol, respectively. However, 1,8-cineol showed no activity at any of the tested concentrations in a contact bioassay. In a fumigation bioassay, carvacrol killed all mites within 50 min after treatment, whereas geraniol, eugenol and 1,8-cineol needed 90 to 150 min. Following a 72 h incubation period in a residual bioassay, carvacrol killed all mites after 4 h of exposure to LC90, while geraniol and eugenol killed all mites only after 8 h exposure. Based on these results, carvacrol was further assessed in vivo. Mite counts in the treatment group were reduced by 98.5 ± 2.4% at 6 weeks post-treatment, while in the control group the mite population had increased. Topical application of carvacrol only caused mild and transient erythema 20 min after treatment. No other side effects were observed. CONCLUSIONS: Considering the strong acaricidal activity of carvacrol in vitro and in vivo and the mild and transient local side effects, carvacrol shows potential as an acaricidal agent in the treatment of P. ovis in cattle.

Associations of environment, health history, T-zone lymphoma, and T-zone-like cells of undetermined significance: A case-control study of aged Golden Retrievers.

BACKGROUND: T-zone lymphoma (TZL), an indolent disease in older dogs, comprises approximately 12% of lymphomas in dogs. TZL cells exhibit an activated phenotype, indicating the disease may be antigen-driven. Prior research found that asymptomatic aged Golden Retrievers (GLDRs) commonly have populations of T-zone-like cells (phenotypically identical to TZL) of undetermined significance (TZUS). OBJECTIVE: To evaluate associations of inflammatory conditions, TZL and TZUS, using a case-control study of GLDRs. ANIMALS: TZL cases (n = 140), flow cytometrically diagnosed, were identified through Colorado State University's Clinical Immunology Laboratory. Non-TZL dogs, recruited through either a database of owners interested in research participation or the submitting clinics of TZL cases, were subsequently flow cytometrically classified as TZUS (n = 221) or control (n = 147). METHODS: Health history, signalment, environmental, and lifestyle factors were obtained from owner-completed questionnaires. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were estimated using multivariable logistic regression, obtaining separate estimates for TZL and TZUS (versus controls). RESULTS: Hypothyroidism (OR, 0.3; 95% CI, 0.1-0.7), omega-3 supplementation (OR, 0.3; 95% CI, 0.1-0.6), and mange (OR, 5.5; 95% CI, 1.4-21.1) were significantly associated with TZL. Gastrointestinal disease (OR, 2.4; 95% CI, 0.98-5.8) had nonsignificantly increased TZL odds. Two shared associations for TZL and TZUS were identified: bladder infection or calculi (TZL OR, 3.5; 95% CI, 0.96-12.7; TZUS OR, 5.1; 95% CI, 1.9-13.7) and eye disease (TZL OR, 2.3; 95% CI, 0.97-5.2; TZUS OR, 1.9; 95% CI, 0.99-3.8). CONCLUSIONS AND CLINICAL IMPORTANCE: These findings may elucidate pathways involved in TZUS risk and progression from TZUS to TZL. Further investigation into the protective association of omega-3 supplements is warranted.

Acaricidal activities of the essential oil from Rhododendron nivale Hook. f. and its main compund, δ-cadinene against Psoroptes cuniculi.

In this paper, the acaricidal activities of Rhododendron nivale Hook. f. and its main compound, δ-cadinene were investigated, and the chemical composition of the essential oil was analyzed. The results showed that among aqueous, 70% ethanols, acetic ether, chloroform, petroleum ether and essential oil extracts from the shoots and leaves, the essential oil showed the best in vitro acaricidal activity against adult P. cuniculi, which occurred in a concentration- and time-dependent manner. The median lethal time (LT50) values of four concentrations (33.33-4.17mg/ml) of the essential oil ranged from 1.476 to 25.900h, respectively. After the treatment of P. cuniculi with the essential oil and ivermectin, infected rabbits were free of scabs or secretions in the ear canal by day 20. Then, the percent yield of essential oil from the leaves and shoots was 2.45% (w/w), which includes 50 compounds. The primary component identified was terpenes, and among of compounds identified from the essential oil of R. nivale the highest relative content was δ-cadinene, which also presented the marked acaricidal activity against Psoroptes cuniculi in vitro. These findings provide evidence for the use of acaricides as a traditional medicine and indicate that the essential oil and δ-cadinene could be used to control mites in livestock.

Sustained release ivermectin-loaded solid lipid dispersion for subcutaneous delivery: in vitro and in vivo evaluation.

This work aimed to develop a sustained release solid dispersion of ivermectin (IVM-SD) in a lipid matrix (hydrogenated castor oil, HCO) for subcutaneous delivery. Solvent-melting technology was employed to prepare IVM-SDs using HCO. The physicochemical properties of the IVM-SDs were evaluated by scanning electron microscopy (SEM), X-ray powder diffraction (XRPD), and Fourier transform infrared spectroscopy (FTIR). The release of IVM from IVM-SDs was evaluated with HPLC in vitro. Pharmacokinetics of IVM was studied in rabbits following a single subcutaneous administration of IVM-SD formulations. The efficacy of IVM-SD against the ear mange mite was evaluated in rabbits. IVM was completely dispersed in HCO in an amorphous state at a drug:carrier ratio lower than 1:3. No chemical interactions between drug and carrier were found besides hydrogen bonding for the amorphous IVM-SDs. The amorphous IVM-SDs formulations exhibited a sustained release of IVM versus physical mixtures (PMs) of IVM and HCO. The drug release decreased as the drug:carrier ratios decreased, and the release kinetics of IVM were controlled via diffusion. Cytotoxicity of IVM-SD to MDCK cells was lower than native IVM. The IVM plasma concentration of SD1:3 remained above 1 ng/mL for 49 d. Higher AUC, MRT, and Tmax values were obtained at a SD1:3 relative to the IVM group. The IVM-SD improved almost 1.1-fold bioavailability of drug compared with IVM in rabbits. IVM-SD could provide longer persistence against rabbit's ear mites than a commercial IVM injection. This study shows that these solid lipid dispersions are a promising approach for the development of subcutaneous IVM formulations.

Artemisia annua contra la leishmaniosis canina: cuatro casos clínicos / Artemisia annua contra a leishmaniose canina: quatro casos clínicos / Artemisia annua against canine leishmaniasis: four clinical cases

La leishmaniosis canina es una enfermedad ampliamente extendida. En España afecta principalmente a la cuenca mediterránea, pero debido a su constante expansión, las zonas endémicas son cada vez mayores. La necesidad de controlarla hace que constantemente surjan nuevos tratamientos y protocolos terapéuticos. En ese sentido, la existencia de remedios naturales con probada efectividad terapéutica y carente de efectos secundarios abre una puerta valiosa en el control y tratamiento de la enfermedad. Artemisia annua contiene artemisinina, una lactona sesquiterpénica que actúa induciendo estrés oxidativo en el parásito, inhibiendo su crecimiento e induciendo su apoptosis. Se presentan cuatro casos clínicos de leishmaniosis canina tratados con preparados de A. annua en los que se han obtenido mejorías significativas (AU)

A leishmaniose e uma doenga com ampla distribuiçáo geográfica: em Espanha, afecta principalmente a bacia do Mediterráneo mas, devido a sua constante expansáo, as suas áreas endémicas sao cada vez maiores. A necessidadede controlar esta doença leva a que surjam constantemente novos tratamentos e protocolos terapéuticos. Nesse sentido, a existencia de fármacos naturais, com eficacia comprovada e desprovidos de efeitos secundários, abre uma porta inestimável para o controle e tratamento da doença. A planta medicinal Artemisia annua contém uma lactona sesquiterpénica, a artemisinina, que actua através de indugáo de stress oxidativo no parasita, inibindo o seu crescimento e induzindo a respectiva apoptose. Neste artigo sao apresentados quatro casos de leishmaniose canina tratados com preparaçóes de A. annua em que foram obtidas melhorias significativas (AU)

Canine leishmaniasis is a widespread disease: in Spain, it mainly affects the Mediterranean basin; but due to its constant expansion, the endemic areas are increasing. Due to the need of control, new treatments and therapeutic protocols constantly appear. In this context, the existence of natural remedies with preven therapeutic effectiveness and lacking side effects opens a valuable gateway in the control and treatment of the disease. Artemisia annua contains artemisinin, a sesquiterpene lactone which induces oxidative stress, inhibits the growth and induces the apoptosis in the parasite. Four clinical cases of canine leishmaniasis treated with A. annua preparations are presented. Significant improvements have been obtained (AU)

Acaricidal activity of oregano oil and its major component, carvacrol, thymol and p-cymene against Psoroptes cuniculi in vitro and in vivo.

Oregano oil possesses marked antioxidant and antimicrobial activity and is widely applied in animal husbandry. In the present study, we aimed to investigate the acaricidal activities of oregano oil and its major component, carvacrol, thymol and p-cymene against Psoroptes cuniculi in vitro and in vivo. The results revealed that oregano oil exhibited significant acaricidal effects against P. cuniculi that were dose- and time-dependent response. In in vitro test, concentrations of 0.05% and 0.02% (v/v) killed all of the mites within 1h and 6h, respectively. Moreover, 0.1mg/ml (w/v) carvacrol, 0.2mg/ml (w/v) thymol and 1% p-cymene (v/v) also possessed marked acaricidal activities, and compared with the control group, elicited mean mortalities of 84.00%, 96.00% and 66% at 24h, respectively. The median lethal times (LT50) against P. cuniculi of the concentrations of 0.02%, 0.01% and 0.005% (v/v) of oregano oil, thymol, carvacrol and p-cymene were 2.171h, 11.396h, 26.102h, and 4.424h, 8.957h and 15.201h, respectively. Meanwhile, twenty naturaly infested rabbits were used to four homogeneity groups: negative control (without treatment), positive control (treated with ivermectin), group treated with 1% of oregano oil and other group with 5% of oregano oil. All the treatments were topically. After the treatment of 1% and 5% oregano oil, the P. cuniculi were completely eliminated in the rabbits, and at the end of the test (day 20), the rabbits of all treatment groups exhibited favorable mental and physical statuses. These results indicated that oregano oil could be widely applied as a potential acaricidal agent in the treatment of animal acariasis in the future.

Primary screen for potential sheep scab control agents.

The efficacy of potential acaricidal agents were assessed against the sheep scab mite Psoroptes ovis using a series of in vitro assays in modified test arenas designed initially to maintain P. ovis off-host. The mortality effects of 45 control agents, including essential oils, detergents, desiccants, growth regulators, lipid synthesis inhibitors, nerve action/energy metabolism disruptors and ecdysteroids were assessed against adults and nymphs. The most effective candidates were the desiccants (diatomaceous earth, nanoclay and sorex), the growth regulators (buprofezin, hexythiazox and teflubenzuron), the lipid synthesis inhibitors (spirodiclofen, spirotetramat and spiromesifen) and the nerve action and energy metabolism inhibitors (fenpyroximate, spinosad, tolfenpyrad, and chlorantraniliprole).

Traps containing carvacrol, a biological approach for the control of Dermanyssus gallinae.

Resistance to conventional synthetic pesticides has been widely reported in Dermanyssus gallinae in different aviary systems. Cardboard traps containing acaricides had been introduced as a successive device for collection and control of the poultry red mite. The present study assessed field efficacy of traps containing carvacrol in the control and reduction of D. gallinae in laying poultry farm. Two different carvacrol-based formulations were tested for their toxicity and possible repellent activity on D. gallinae to determine the most appropriate formulation and concentration to be used in the field study. In vitro tests confirmed that 1 % carvacrol formulation with ethoxylated castor oil as emulsifier was significantly toxic to D. gallinae without any dissuading effect in comparison to ethanol and higher concentrations of carvacrol (p < 0.05). A subsequent in vivo experiment in a cage system laying farm demonstrated significant acaricidal activity for traps containing 1 % carvacrol. Throughout the study, untreated cardboard traps were used for monitoring mite populations. Carvacrol-impregnated traps were efficacious in the control of D. gallinae and led to over 92 % reduction in mite's population after 2 week of application. Toxic effects of carvacrol maintained through 2 weeks after the last application of traps. Results of the present study suggested that effective control of the poultry red mite can be achieved by traps containing carvacrol. These traps can be used safely in poultry facilities without any concern about residues in eggs, meat, and environment.

Animal health: Tackling a mitey problem.

The poultry ectoparasite Dermanyssus gallinae, known to poultry farmers as 'red mite', has a negative impact on animal health and is a vector of viruses and bacteria. It also sometimes attacks poultry farm workers, and human infestations have been reported originating from pigeons' nests in urban areas. A European project is currently investigating synergistic and holistic approaches to improving the health, welfare and productivity of laying hens through more effective prevention and control of the red mite. Kathryn Bartley reports from a two-day conference held in Italy in May, which provided an update on progress with the project.

Clinical efficacy of 9-oxo-10, 11-dehydroageraphorone extracted from Eupatorium adenophorum against Psoroptes cuniculi in rabbits.

BACKGROUND: Animal acariasis is one of the important veterinary skin diseases. Chemical drugs have been widely used to treat and control this kind of disease. But many chemicals control could increase resistance in target species, toxicity and environmental hazards. We found that the 9-oxo-10, 11-dehydroageraphorone (euptox A) extracted from E. adenophorum has strong toxicity against P. cuniculi in vitro, but the in vivo acaricidal actions of euptox A have yet to be investigated. RESULTS: A 14-day experiment was performed using rabbits that were naturally infested with P. cuniculi on a farm. Rabbits were randomly divided into five groups; animals in groups A, B and C were treated in each ear topically with 4.0 ml of 2.0 and 1.0 g/L (w/v) euptox A, respectively. Animals in groups D and E were treated with ivermectin (by injection; positive controls) and glycerol with water only (by embrocation; negative controls), respectively. Each rabbit was treated twice with separate treatments on days 0 and 7. Rabbits were observed daily and detailed examinations were performed on days 0, 7 and 14, to inspect the presence or absence of mites and scabs/crusts. Seven days after the initial treatment, the mean clinical scores (presence of scabs/crusts) decreased from 3.48, 3.37, 3.43 and 3.45 to 0.37, 0.42, 0.78 and 0.38 in the ears of animals in groups A, B , C and D, respectively, which were similar to the observations recorded in the positive control rabbits. However, the clinical score for negative control rabbits did not increase significantly (P > 0.05) during the experiment, and this changed from 3.32 to 3.37 in the ears, and there were no significant differences in clinical efficacy between left and right ears. After two treatments (0 and 7 d), the rabbits in groups A, B, C and D had recovered completely 14 days after the last treatment and no recurrences of infection were observed. CONCLUSIONS: These results indicate that euptox A was potent compounds for the effective control of animal P. cuniculi in vivo.

The field efficacy of garlic extract against Dermanyssus gallinae in layer farms of Babol, Iran.

Dermanyssus gallinae (Acari: Mesostigmata) is the most important hematophagous ectoparasite in layer farms in many countries. The reproduction rate of the parasite is rapid and can be completed in a week under favorable conditions. The parasite has direct and indirect effects on birds. It can also act as a vector for some important pathogens. Many researchers have investigated the effects of essential oils, plant extracts, oriental medicinal plant extracts, and silica against red mite. They can be used as killing agents or repellents. In the present study, the effect of garlic (Allium sativum) extract was investigated for controlling red mite infestation in a layer farm in Babol, North of Iran. Our results showed that the extract was effective and we obtained a 96% success after two successive sprays.

Acaricidal activity of petroleum ether extracts from Eupatorium adenophorum against the ectoparasitic cattle mite, Chorioptes texanus.

In this study, we evaluated the acaricidal efficacy of extracts obtained from the plant Eupatorium adenophorum against the common cattle mite Chorioptes texanus. The results showed that 95% ethanol extracts at concentrations of 1.0, 0.5, and 0.25 g/mL (w/v) were highly toxic to C. texanus in vitro, killing 100% of mites in 4 h. Similarly, petroleum ether extracts of E. adenophorum resulted in between 80 and 100% mortality of mites in vitro at concentrations of 0.1, 0.05, and 0.025 mL/mL (v/v) within 4 h. In clinical trials, all infected individuals completely recovered after two treatments administered at 7-day intervals and remained disease-free at 60 days posttreatment. The clinical effect of treatment with E. adenophorum petroleum ether extracts was similar to that of treatment with the acaricide fenvalerate. These results indicated that E. adenophorum contains novel potential acaricidal compounds that can effectively control mites in livestock.

Supplementing with vitamin C the diet of honeybees (Apis mellifera carnica) parasitized with Varroa destructor: effects on antioxidative status.

We studied a total of eight developmental stages of capped brood and newly emerged workers of Apis mellifera carnica colonies naturally parasitized with Varroa destructor. During winter and early spring four colonies were fed syrup containing 1.8 mg vitamin C kg(-1) (ascorbic acid group; group AA) while four colonies were fed syrup without the vitamin C (control group C). Selected elements of the antioxidative system were analysed including total antioxidant status (TAS), glutathione content and antioxidative enzyme activities (superoxide dismutase, catalase, peroxidase and glutathione S-transferase). Body weight, protein content and indices of infestation were also determined. The prevalence (8.11%) and intensity (1·15 parasite per bee) of the infestation were lower in group AA compared with group C (11.3% and 1.21, respectively). Changes in the indicators of antioxidative stress were evidence for the strengthening of the antioxidative system in the brood by administration of vitamin C. In freshly emerged worker bees of group AA, despite the infestation, protein content, TAS, and the activity of all antioxidative enzymes had significantly higher values in relation to group C.

New Miticides for Integrated Pest Management of Varroa destructor (Acari: Varroidae) in Honey Bee Colonies on the Canadian Prairies.

Varroa destructor Anderson and Trueman 2000 (Acari: Varroidae) is an ectoparasitic mite of the honey bee, Apis mellifera L. (Hymenoptera: Apidae). Honey bee colonies require extensive management to prevent mortality caused by varroa mites and the viruses they vector. New miticides (Thymovar and HopGuard) to manage varroa mites were evaluated during the spring and fall treatment windows of the Canadian prairies to determine their effectiveness as part of an integrated management strategy. Thymovar and HopGuard were evaluated alongside the currently used industry standards: Apivar and formic acid. Results demonstrated that Apivar and formic acid remain effective V. destructor management options under spring and fall conditions. Applications of Thymovar during spring were associated with a reduction in brood area, and therefore should be limited to the fall season. The miticide HopGuard was not effective in managing V. destructor, and alteration of the current delivery system is necessary. This study demonstrates the potential for new effective treatment options to supplement currently used V. destructor integrated pest management systems.