The sensitivity of Demodex canis (Acari: Demodicidae) to the essential oil of Melaleuca alternifolia – an in vitro study

Abstract

The essential oil of the Melaleuca alternifolia (Maiden & Betche) (tea tree oil) has been effective in previous studies, in the treatment of infestation by Demodex mites in humans. The present study aimed at evaluating the in vitro acaricidal effect of this herbal medicine on Demodex canis. For the parasitological examination, samples were collected from a dog’s skin and examined using optical microscopy. Only samples with intact mites and with evident movement of chelicerae and tarsi were selected. Twenty-one samples were tested with the oil, in seven different concentrations: 100%; 50%; 25%; 12.5%; 6.25%; 5.0% and 3.13%. Three samples were tested with the positive control amitraz, and three with the negative control neutral shampoo. The interval between the time the solution was added and the moment the movement of the last mite ceased defined the survival time in the sample. By comparing the times at different concentrations and controls, the results showed that the higher the concentration of the oil, the more quickly its lethal effect occurred, and that the survival times in the controls were longer than in the different concentrations of melaleuca oil.

Antiparasitic Activity of Tea Tree Oil (TTO) and Its Components against Medically Important Ectoparasites: A Systematic Review

“…Our review found that TTO and its components (mainly T4O) can completely eradicate Demodex mites and reduce mite-related symptoms without any serious AEs, as evidenced by multiple studies (Tables 1 and 2). The efficacy reported in clinical studies was consistent with the in vitro results of laboratory-based studies and results reported for veterinary Demodex mites (D. canis), where the survival time of mites was 8-100 min for TTO (3.125-100%) [122]. Demodex mites (Demodex folliculorum and D. brevis) are the most common permanent ectoparasites in humans, infesting the pilosebaceous unit of the face and scalp skin to cause demodicosis [7,123].…”

In vitro toxicity of combination of Amitraz and Carvacrol on Demodex canis

“…This presented study was conducted based on the procedures followed in other studies with similar objectives ( Walton et al ., 2004 ; Tighe et al ., 2013 ; Neves et al ., 2020 ). Twenty selected samples were randomly allocated to one of four study groups consisting of five samples in each group.…”

“…The initial microscopy was done at a magnification of 10× and mites were followed by zigzag line microscopy observation for 5 minutes at 5-minute intervals thereafter. After the time that mites lost their motility and were suspected death of each mite, the magnification of 40× was employed to observe the motility or lack of motility of chelicerae and tarsi of the mites continuously for 1 minute during the time of study to ensure whether a mite was alive or dead ( Gao et al ., 2005 ; Tighe et al ., 2013 ; Neves et al ., 2020 ).…”

“…Previous studies have reported that different herbal essential oils and their bioactive components of them, especially tea tree oil have great acaricidal efficacy against mites of the Demodex genus ( Demodex folliculorum and Demodex brevis ) in humans ( Gao et al ., 2005 ; Savla et al ., 2019 ; Akkucuk and Kaya, 2022 ). Also, there was just one article that evaluates the in vitro acaricidal effect of tea tree oil as a herbal essential oil on D. canis mites ( Neves et al ., 2020 ). Despite thyme oil and carvacrol as the most important active ingredients, it was evaluated for the killing of D. folliculorum and D. brevis in humans and shown great and more effective mite killing in comparison with tea tree oil, black seed oil, St. John's Wort oil, and sage oil ( Akkucuk and Kaya, 2022 ).…”

Revisión bibliográfica: demodicosis canina

“…La demodicosis canina puede presentarse de forma leve localizada que suele resolverse de forma espontánea en la gran parte de los casos sin necesidad de tratamiento a menos que se presente una enfermedad secundaria con bacterias donde se procede administrar acaricidas, pero si su presentación es grave generalizada si necesita tratamiento y el medico debe dar a conocer los protocolos que se van a utilizar al propietario para que ellos puedan ser constantes y consientes (28).…”