Daily ivermectin for treatment of generalized demodicosis in dogs

Abstract Twelve dogs with generalized demodicosis were treated with oral administration of ivermectin, 0.4 mg kg^-1 of body weight given once every 24 h. Results of skin scrapings were used to determine whether administration of ivermectin should be continued or stopped. Dogs that were free of clinical signs of demodicosis 12 months after administration of ivermectin was discontinued were considered cured. Five dogs were cured. The medían duration of treatment was 15 weeks (range 5–21 weeks). Seven dogs were failures, with five relapsing 3–11. 5 months after treatment was stopped, and two having persistent demodicosis in spite of treatment. Mild ivermectin toxicosis developed in one dog after 5 weeks of treatment; side-effects resolved shortly after the treatment was stopped. Resumen Se trataron doce perros con demodicosis generalizada con ivermectina oral, 0.4 mg/Kg de peso corporal una vez cada 24 h. Se realizaron raspados cutáneos para déterminar si debia retirarse o continuar con la administración de ivermectina. Se consideraron curados aquellos perros sin sintomatologia de demodicosis 12 meses después de retirar la terapia con ivermectina. La duración medía del tratamiento con ivermectina fue de 15 semanas (rango de 5–21). Se fracasó en siete perros, con cinco recidivas a los 3–11, 5 meses después de parar la terapia y dos con demodicosis persistente a pesar del tratamiento. Un perro desarrolló una toxicosis leve a la ivermectina a las 5 semanas del tratamiento; los efectos secundarios desaparecieron al poco de retirar el tratamiento. [Medleau, L., Ristic, Z., McElveen, D.R. Daily ivermectin for treatment of generalized demodicosis in dogs (Administración díaria de ivermectina para el tratamiento de le demodicosis generalizada en el perro). Veterinary Dermatology 1996; 7 : 209–212.] Résumé Douze chiens présentant une démodécie généralisée fürent traités par administration orale d'ivermectine à la dose de 0.4 mg/kg de poids une fois par jour. Les résultats des raclages cutanés servirent à déterminar la nécessité de continuer ou d'arrêter l'administration d'ivermectine. Les chiens ne présentant aucun symptôme de démodécie 12 mois après l'arrêt de l'ivermectine fürent considérés guéris. Cinq chiens fürent guéris. La durée moyenne du traitement fut de 15 semaines (intervalles de 5 à 21 semaines. Sept cas fürent des échecs, avec 5 chiens récidivant 3 à 11, 5 mois après l'arrêt du traitement, et 2 présentant une démodécie persistante malgré le traitement. Un chien a développé une intoxication modéree après 5 semaines de traitement; les effets secondaires disparaissant rapidement après l'arrêt du traitement. [Medleau, L., Ristic, Z., McElveen, D.R. Daily ivermectin for treatment of generalized demodicosis in dogs (Administration quotidienne d'ivermectine dans le traitement de la démodécie généralisée chez le chien). Veterinary Dermatology 1996; 7 : 209–212.] Zusammenfassung Zwölf Hunde mit generalisierter Demodikose wurden mit einer oralen Verabreichung von Ivermectin in der Dosierung von 0, 4 mg/kg Körpergewicht einmal alle 24 Stunden behandelt. Die Ergebnisse der Hautgeschabsel dienten zur Bestimmung, ob die Verabreichung weiterhin erfolgen sollte oder abzubrechen sei. Hunde, die 12 Monate nach Ende der Ivermectin-Verabreichung frei von klinischen Symptomen der Demodikose waren, wurden als geheilt betrachtet. Fünf Hunde waren geheilt. Die mittlere Therapiedauer betrug 15 Wochen (Spannweite 5 bis 21 Wochen). Bei sieben Hunden versagte die Therapie, wobei fünf nach 3 bis 11, 5 Monaten nach Behandlungsende ein Rezidiv bekamen und zwei Tiere trotz der Therapie einer persistierende Demodikose zeigten. Bel einem Hund entwickelte sich 5 Wochen nach der Behandlung eine milde Ivermectin-Intoxikation; die Nebenwirkungen verschwanden kurz nach Abbruch der Therapie. [Medleau, L., Ristic, Z., McElveen, D.R. Daily ivermectin for treatment of generalized demodicosis in dogs (Tägliche Ivermectinverabreichung als Behandlung für Hunde mit generalisierter Demodikose). Veterinary Dermatology 1996; 7 : 209–212.]     

Topical (pour-on) ivermectin in the treatment of chronic generalized demodicosis in dogs

Twelve privately owned dogs with chronic generalized demodicosis were treated topically along the dorsal midline with 1.5 mg kg⁻¹ of 0.5% pour-on ivermectin for cattle three times per week for 3–6 months. All 12 dogs had a substantial reduction in clinical signs and in the number of Demodex canis mites found on skin scrapings. Only two dogs, however, became skin-scrapings negative after 3 and 5 months of treatment, respectively. In these two dogs treatment was prolonged for an additional 4 weeks past the negative scrapings. One dog relapsed 2 months after cessation of therapy; the other is still free of symptoms 1.5 years later. The cure rate, based on the lack of recurrence of clinical signs for 12 months after discontinuation of ivermectin administration, was 1 of 12 dogs (8%). Adverse reactions were not seen.     

Treatment protocols for demodicosis: an evidence-based review

Publications discussing the treatment of demodicosis in the dog and cat are reviewed. Based on the evidence in the literature, amitraz rinses at 0.025-0.06% every 7-14 days, and oral daily ivermectin at 300 micro g kg(-1), milbemycin at 2 mg kg(-1) and moxidectin at 400 micro g kg(-1), respectively, can all be recommended for the treatment of generalized canine demodicosis. Ivermectin and moxidectin should be initiated at lower doses and patients monitored for possible adverse effects during therapy. In cats, 2% lime sulfur dips and amitraz rinses at 0.0125-0.025% have been used successfully.     

Efficacy of 1.25% amitraz solution in the treatment of generalized demodicosis (eight cases) and sarcoptic mange (five cases) in dogs

Eight dogs with generalized demodicosis and five with sarcoptic mange were treated with 1.25% amitraz solution applied weekly and associated with an antidote treatment (atipamezol, 0.1 mg kg⁻¹ IM once: and yohimbine 0.1 mg kg⁻¹ once daily for 3 days, orally). Results of skin scrapings were used to determine whether therapy should be continued or stopped. The median number of treatments for demodicosis and sarcoptic mange was three (range 2–5) and two (range 1–3), respectively. Some side-effects were observed but all were stopped with antidote treatment; no failure or relapses occurred at 6–36 months after treatment.     

Efficacy of milbemycin oxime in the treatment of canine generalized demodicosis: a retrospective study of 99 dogs (1995-2000)

Ninety-nine dogs diagnosed with generalized demodicosis were treated with milbemycin oxime. Cases diagnosed before two years of age were classified as juvenile-onset (53%) and those diagnosed after two years of age as adult-onset (47%). Dogs were considered cleared of mites when none could be demonstrated in scrapings and cured if no relapse was seen for 12 months. Eighty-five per cent (84/99) were cured with milbemycin oxime used for 1-6 months (mean 2.3 months) at a dosage of 0.5-1.6 mg kg-1 body weight (mean 0.75 mg kg-1). No significant difference in dosage or treatment time was seen between juvenile and adult cases. Chance of cure was significantly better in young animals (cured cases mean age 2.97 years) than in older animals (not cured cases mean age 8.02 years). Start of treatment early in the course of disease gave a significantly better chance of cure. Cases with severe pododemodicosis had less chance of a cure (9/11 not cured).     

Investigation of pharmacokinetic interaction between ivermectin and praziquantel after oral administration in healthy dogs

The purpose of this study was to determine the pharmacokinetic interaction between ivermectin (0.4 mg/kg) and praziquantel (10 mg/kg) administered either alone or co‐administered to dogs after oral treatment. Twelve healthy cross‐bred dogs (weighing 18–21 kg, aged 1–3 years) were allocated randomly into two groups of six dogs (four females, two males) each. In first group, the tablet forms of praziquantel and ivermectin were administered using a crossover design with a 15‐day washout period, respectively. Second group received tablet form of ivermectin plus praziquantel. The plasma concentrations of ivermectin and praziquantel were determined by high‐performance liquid chromatography using a fluorescence and ultraviolet detector, respectively. The pharmacokinetic parameters of ivermectin following oral alone‐administration were as follows: elimination half‐life (t_1/2λz) 110 ± 11.06 hr, area under the plasma concentration–time curve (AUC_0–∞) 7,805 ± 1,768 hr^.ng/ml, maximum concentration (C_max) 137 ± 48.09 ng/ml, and time to reach C_max (T_max) 14.0 ± 4.90 hr. The pharmacokinetic parameters of praziquantel following oral alone‐administration were as follows: t_1/2λz 7.39 ± 3.86 hr, AUC_0–∞ 4,301 ± 1,253 hr^.ng/ml, C_max 897 ± 245 ng/ml, and T_max 5.33 ± 0.82 hr. The pharmacokinetics of ivermectin and praziquantel were not changed, except T_max of praziquantel in the combined group. In conclusion, the combined formulation of ivermectin and praziquantel can be preferred in the treatment and prevention of diseases caused by susceptible parasites in dogs because no pharmacokinetic interaction was determined between them.     

Evaluation of interleukin-2 production and interleukin-2 receptor expression in dogs with generalized demodicosis

Abstract The experimental hypothesis testéd was that dogs with generalized demodicosis have significantly lower levels of interleukin-2 (IL-2) production and IL-2 receptor expression as compared with normal dogs. The specific objective of this study was to compare the production of IL-2 and IL-2 receptor expression of peripheral blood mononuclear cells in normal dogs and dogs with generalized demodicosis. Ten dogs with juvenile-onset generalized demodicosis were evaluated. Dogs with generalized demodicosis had a significantly lower in vitro lymphocyte blastogenesis response (P < 0.006), fewer cells expressing IL-2 receptors (P < 0.03), and decreased IL-2 production (P < 0.01) than control dogs. Resumen La hipótesis experimental fue que los perros con demodicosis generalizada tienen niveles significativamente inferiores de producción y expresión de receptores de interleuquina-2 (IL-2) comparado con perros normales. El objetivo especifico de este estudio fue el de comparar le producción y expresión de receptores de IL-2 en células mononucleares de sangre periférica en perros normales y en perros con demodicosis generalizada. Se evaluaron diez perros con demodicosis generalizada iniciada en edad temprana. Los perros con demodicosis generalizada tenian in vitro una respuesta blastogénica linfocitaria inferior (P < 0.006), menos células con expresión de receptores de IL-2 (P < 0.03) y una disminución en la producción de IL-2 (p<0.01) respecto a los perros control. [Lemarie, S.L., Horohov, D.W. Evaluation of interleukin-2 production and interleukin-2 receptor expression in dogs with generalized demodicosis. (Evaluación de la producción y expresión de recepetores de interleuquina-2 en perros con demodicosis generalizada.) Veterinary Dermatology 1996; 7 : 213–219.] Résumé L'hypothèse expérimentale est que les chiens à démodécie généralisée présente une diminution significative du taux d'interleukine 2 (IL-2) et de l'expression des récepteurs de l'interleukine 2 comparativement à des chiens sains. L'objectif de cette étude est de comparer la production d'I12 et l'expression des récepteurs de l'IL-2 par des lymphocytes sanguins périphériques de chiens témoins et de chiens atteints de démodécie généralisée. Dix chiens avec une démodécie généralisée juvenile ont été testés. Les chiens à démodécie généralisée présentent une transformation lymphoblastique plus basse (p< 0.006), moins de cellules exprimant les récepteurs IL-2 (p<0.03) et une diminution de la production d'IL-2 (p<0.01) par rapport aux chiens témoins. [Lemarie, S.L., Horohov, D.W. Evaluation of interleukin-2 production and interleukin-2 receptor expression in dogs with generalized demodicosis. (Evaluation de la production d'interleukine 2 et de l'expression des récepteurs de l'interleukine 2 chez des chiens à démodécie généralisée.) Veterinary Dermatology 1996; 7 : 213–219.] Zusammenfassung Es wurde die experimentelle Hypothese getestét, daß Hunde mit generalisierter Demodikose über signifikant niedrigere Spiegel an Interieukin2-(IL-2)Produktion und IL-2-Rezeptorexpression verfügen im Vergleich zu gesunden Hunden. Der wesentilche Gegenstand dieser Untersuchung war, die Produktion von IL-2 und die IL-2Rezeptorexpression in den mononukleären Zellen des peripheren Blutes bei gesunden Hunden und solchen mit generalisierter Demodikose zu vergleichen. Zehn Hunde mit juvenilem Beginn von generalisierter Demodikose wurden untersucht. Hunde mit generalisierter Demodikose hatten eine signifikant niedrigere in vitro-Reaktion der Lymphozytenblasogenese (P < 0, 006), weniger Zellen, die IL-2Rezeptoren zeigten (P < 0,03) und eine verminderte IL-2Produktion (P < 0,01) als die Kontrollhunde. [Lemarie, S.L., Horohov, D.W. Evaluation of interleukin-2 production and interleukin-2 receptor expression in dogs with generalized demodicosis (Untersuchungen über die Interleukin2-Produktion und Interleukin2-Rezeptorexpression bei Hunden mit generalisierter Demodikose) Veterinary Dermatology 1996; 7 : 213–219.]     

Efficacy of daily amitraz on generalised demodicosis in dogs

Fifty dogs with generalised demodicosis were treated with daily applications of 0·125 per cent amitraz solution over half the body. This was applied once a day, alternating the body half treated. Nine dogs were lost to follow-up; the remaining dogs were classified as either a success (25 dogs, 61 per cent) or a failure (16 dogs, 39 per cent) according to their response to treatment. Eight of the failures were due to persistent demodicosis and eight relapsed within one year after treatment. All eight of the relapsed dogs were cured after a second course of daily amitraz treatment. For the 25 dogs considered treatment successes, the median duration of treatment was 6·5 weeks (range, three weeks to nine months), and the median interval from completion of treatment to last post treatment evaluation was 3·4 years (range, two to four-and-a-half-years). Including the eight dogs that were cured after retreatment, the daily amitraz applications were curative in 33 of 41 dogs (80 per cent) with generalised demodicosis.     

Use of lufenuron for treatment of generalized demodicosis in dogs

Abstract The efficacy of lufenuron for treatment of generalized demodicosis in dogs was investigated. Eleven dogs with generalized demodicosis received either low-dose lufenuron (mean 13.3 mg kg^-1 once a day on the first 5 days of the month) or high-dose lufenuron (mean 15.8 mg kg^-1 three times a week) orally for 2 or 3 months. None of the dogs showed a decrease in mite numbers on monthly examination of deep skin scrapings. To determine levels of orally administered lufenuron in the skin (epidermis and dermis), three adult dogs were each given lufenuron orally at a mean dose of 19.3 mg kg^-1 once a day for 5 days. Lufenuron was measured in samples of blood and skin collected on days 0, 1, 6, 16, 30, 44 and 60 after administering the drug. Mean skin levels of lufenuron were 10 times the corresponding blood levels. Lufenuron was ineffective as a treatment for generalized demodicosis in these dogs despite the fact that high drug levels were achieved in the skin. Résumé— L'efficacitée du Lufénuron dans le traitement de la démodécie généralisée du chien a étéévaluée 11 chiens présentant une démodécie généralisée ont reçu soit du lufeAnuron à dose faible (en moyenne 13, 3 mg kg^-1, 1 fois par jour les 5 premiers jours de chaque mois) ou à dose élevée (en moyenne 15, 8 mg kg^-1 fois par semaine) par voie orale pendant 2 à 3 mois. Aucun des chiens traités ne montre une diminution du nombre de parasites determine à partir de raclages cutanés profonds mensuels. Afin de déterminer les taux de lufénuron dans la peau (épiderme et derme), trois chiens adultes ont reçu chacun du lufénuron par voie orale à une dose moyenne de 19, 3 mg kg^-1, une fois par jour pendant 5 jours. Le lufénuron a été mesuré dans des échantillons sanguins et cutanés à JO, J1, J6, J16, J30, J44 et J60 après administration. Les taux moyens dans la peau sont 10 fois supérieurs aux taux sanguins correspondants. Le lufénuron est inefficace dans le traitement de la démodécie généralisée en dépit des concentrations élévées dans la peau. [Schwassmann, M., Kunkle, G. A., Hepler, D. I., Lewis, D. T. Use of lufénuron for treatment of generalized demodicosis in dogs. (Utilisation du Lufénuron pour le traitement de la démodécie généralisée du chien.) Veterinary Dermatology 1997; 8 : 11–18.] Resumen Se investigó la eficacia de lufénuron para el tratamiento de la demodicosis generalizada en perros. Once perros con demodicosis generalizada recibieron o bien una dosis baja de lufénuron (medía 13.3 mg kg^-1 una vez al día en los primeros 5 meses del mes) o una dosis alta de lufénuron (medía 15.8 mg kg^-1 3 veces a la semana) oralmente durante 2 o 3 meses. Ninguno de los perros mostró dismunición en el número de ácaros en los exámenes mensuales de raspados cutáneos profundos. Para detectar en la piel (epidermis y dermis) los niveles de lufénuron administrado oralmente, a tres perros adultos se les administró a cada uno lufénuron oral a una dosis medía de 19.3 mg kg^-1 una vez al día durante 5 días. Se cuantificó el lufénuron en muestras de sangre y piel tomadas a días 0, 1, 6, 16, 30, 44 y 60 después de la administración del fármaco. Los valores cutáneos medios de lufénuron fueron 10 veces los valores sanguineos correspondientes. Lufénuron no tuvo efecto como tratamiento de la demodicosis generalizada en estos perros a pesar de los altos niveles farmacológicos alcanzados a nivel cutáneo. [Schwassmann, M., Kunkle, G. A., Hepler, D. I., Lewis, D. T. Use of lufénuron for treatment of generalized demodicosis in dogs. (Uso de lufénuron para el tratamiento de la demodicosis generalizada en perros.) Veterinary Dermatology 1997; 8 : 11–18.] Zusammenfassung— Die Wirksamkeit von Luferunon in der Behandlung von generalisierter Demodikose wurde untersucht. Elf Hunde mit generalisierter Demodikose erhielten entweder eine niedrige (durchschnittlich 13.3 mg kg^-1 täglich an den ersten fünf Monatstagen) oder hohe Dosis Lufénuron (durchschnittlich 15.8 mg kg^-1 dreimal wöchentlich) oral für 2–3 Monate. Bei keinem Hund zeigte die monatliche Untersuchung von tiefen Hautgeschabseln eine Verminderung der Milbenanzahl. Um den Hautspiegel (Epidermis und Dermis) des oral verabreichten Lufénurons zu bestimmen, erhielten drei Hunde jeweils oral Lufénuron in einer Durchschnittsdosis von 19.3 mg kg^-1 täglich für 5 Tage. Lufénuron wurde in Serum-und Hautproben gemessen die vor und 1, 6, 16, 30, 44 und 60 Tage nach Beginn der Medikamenteneinnahme genommen wurden. Durchschnittliche Hautspiegel von Lufénuron waren zehn Mai so hoch wie die korrespondierenden Blutspiegel. Die Behandlung der generalisierten Demodikose mit Lufénuron war trotz der hohen Medikamentenkonzentration in der Haul unwirksam. [Schwassmann, M., Kunkle, G. A., Hepler, D. I., Lewis, D. T. Use of lufénuron for treatment of generalized demodicosis in dogs. (Die Verwendung von Lufénuron für die Behandlung der generalisierten Demodikose beim Hund.) Veterinary Dermatology 1997; 8 : 11–18.]     

A retrospective study of juvenile- and adult-onset generalized demodicosis in dogs (1986–91)

Abstract The medical records of 81 dogs (47 juvenile, 34 adult) with generalized demodicosis were reviewed. There was a significant difference in the distribution of breeds (juvenile P < 0.002, adult P < 0.001; chi squared) presented for demodicosis compared with the distribution of the same breeds presented to our practice during the same time period. Cocker Spaniels and mixed-breed dogs were likely to be under-represented in both the adult- and juvenile-onset groups. Significantly more miticidal treatments were required to achieve clinical remission in adult dogs with pustular demodicosis compared with juvenile dogs with pustular disease (P < 0.05; Kruskall-Wallis). Concurrent disease and associated drug administration were assessed for adult dogs with demodicosis. Of dogs with concurrent conditions (n=15), administration of corticosteroids and endogenous hyperadrenocorticism were recognized most often (10/15). Concurrent neoplastic, infectious, parasitic or metabolic disease was uncommon in dogs with adult-onset demodicosis. Résumé— Les dossiers médicaux de 81 chiens présentant des démodécies généralisées (47 formes juvéniles, 34 formes adultes) ont été analysés. Il existait une différence significative (forme juvénile P < 0.002, forme adulte P < 0.001) dans la distribution des races présentées pour démodécie par rapport aux mêmes races présentées à notre consultation à la même époque. Les cockers spaniels et les chiens métissés sont sous - représentés dans les deux groupes. Le nombre de traitements acaricides nécessaires pour obtenir une rémission clinique était significativement plus élevé chez les chiens adultes présentant une démodécie pustulcuse que chez les jeunes (P < 0.05; Kruskall-Wallis). La présence de pathologies intercurrentes ou iatrogènes a été recherchée chez les chiens adultes. Chez les chiens présentant une pathologie intercurrente (n=15), les diagnostics les plus fréquents (10/15), étaient l'administration de corticoïdes ou un hypercorticisme endogène. Une pathologie intercurrente de type néoplasique, infectieuse, parasitaire ou métabolique est rarement associée à la forme adulte de démodécie canine. [Lemarié, S.L., Hosgood G., Foil C.S. A retrospective study of juvenile- and adult-onset generalized demodicosis in dogs (1986–91) (Analyse retrospective de formes juveniles et de formes adultes de demodecie generalisee chez le chien (1986–91). Veterinary Dermatology 1996; 7 : 3–10.] Resumen Se revisó la historia médica de 81 perros (47 jóvenes, 34 adultos) con demodicosis generalizada. Habia diferencias significativas en la distribución de razas (jóvenes P < 0.002, adulto P < 0.001; chi cuadrado) con una presentación de demodicosis comparado con la distribución de las mismas razas que se presentaron en nuestra consulta durante el mismo período. Los Cocker Spaniel y los cruzados tenían menos posibilidades de presentarse tanto en el grupo de perros jóvenes como en el de adultos. Se necesitaron tratamientos significativamente más miticidas para consequir curación clínica en los perros adultos con demodicosis pustular comparado con los perros jóvenes con presentación pustular (P < 0.05; Kruskall-Wallis). Se detectaron con mayor frecuencia enfermedades concomitantes (n = 15), administración de corticosteroides e hiperadrenocorticismo endógeno (10/15). Fueron poco frecuentes las enfermedades neoplásicas, infecciosas, parasíticas o metabólicas en los casos de demodicosis del adulto. [Lemarié, S.L., Hosgood G., Foil C.S. A retrospective study of juvenile- and adult-onset generalized demodicosis in dogs (1986–91) (Estudio retrospectivo de la demodicosis canina en el adulto y en el perro joven (1986–91). Veterinary Dermatology 1996; 7 : 3–10.] Zusammenfassung— Die Krankenblätter von 81 Hunden (47 juvenil, 34 adult) mit generalisierter Demodikose kamen zur Auswertung. Es bestand einer signifikanter Unterschied in der Verteilung der Rassen (juvenil P < 0,002, adult P < 0,001; Chi-quadrat), die wegen Demodikose vorgestellt wurden, im Vergleich zur der Verteilung der selben Rassen, die während des gleichen Zeitabschnitts in unserer Praxis kamen. Cockerspaniel und Mischlinge schienen unterrepräsentiert sowohl in der Adult- wie in der Juvenil-Demodikosegruppe. Es wurden signifikant mehr akarizide Behandlungen für das Erreichen einer klinischen Remission bei adulten. Hunden mit pustulärer Demodikose benötigt im Vergleich zu juvenilen Hunden mit pustulärer Erkrankung (P < 0,05; Kruskall-Wallis). Bestehende Krankheit und die damit verbundene Arzneimittelanwendung wurden bei adulten Hunden mit Demodikose ausgewertet. Bei Hunden mit bestehenden Krankheitsbildern (n = 15) wurde am häufigsten die Verabreichung von Kortikosteroiden und endogener Hyperadrenokortizismus festgestellt (10/15). Gleichzeitige neoplastische, infektiöse, parasitäre oder stoffwechselbedingte Erkrankung war bei Hunden mit adult-beginnender Demodikose selten. [Lemarié, S.L., Hosgood G., Foil C.S. A retrospective study of juvenile- and adult-onset generalized demodicosis in dogs (1986–91) (Retrospektive Studie über juvenil- und adult-beginnende Demodikose beim Hund (1986–91). Veterinary Dermatology 1996; 7 : 3–10.]     

Influence of systemic antibiotics on the treatment of dogs with generalized demodicosis

Canine generalized demodicosis (CGD) is a skin disease with distinct breed predispositions. Secondary bacterial infections are common. Dogs typically receive miticidal therapy in combination with antibacterial treatment. Whether antibiotics influence the duration of acaricidal therapy is unknown at the moment. There is also debate over how common short-tailed Demodex mites occur in demodicosis. This study evaluated the influence of systemic antibiotics on the course of CGD, the occurrence of short-tailed Demodex mites in demodectic dogs and the influence of furunculosis on treatment outcome. Breed predispositions for CGD in Moscow were identified. Fifty-eight dogs were randomly distributed in two groups. Both were treated with ivermectin 600 mcg/kg q24h orally and benzoyl peroxide shampoo weekly. The dogs in one group (AB) were additionally treated with systemic antibiotics for at least 1 month, dogs in the other group (NAB) were not. Monthly examinations, skin scrapings and impression smears were performed. Prior to the study there was no difference in clinical severity, presence of pyoderma and mite numbers between groups. There was no significant difference in duration until first negative skin scrapings and resolution of bacterial infection. In dogs with furunculosis the number of the mites was significantly higher than in dogs without furunculosis but the duration until microscopic remission albeit longer, was not significantly different. Short-tailed Demodex mites were found in 25% of the cases. Pugs and English Bulldogs were predisposed. Based on these results, systemic antibiotics may not impact as much as previously thought on the actual success of CGD treatment.     

Biovailability of ivermectin administered orally to dogs

The bioavailability of three formulations of ivermectin was determined following oral administration to dogs. The average peak plasma level (C _max) of ivermectin administered in the standard tablet formulation at 6 and 100 µg/kg of body weight was 2.97 and 44.31 ng/g, respectively. This suggest dose-dependent pharmacokinetics.C _max and total ivermectin bioavailability, as assessed from the area under the plasma curve (AUC), were similar between two tablet formulations of ivermectin administered at 100 µg/kg. Furthermore,C _max was similar following administration of radiolabelled ivermectin at 6 µg/kg in either a beef-based chewable formulation or in the standard tablet formulation.     

Binding characteristics of ivermectin in plasma from collie dogs

Two types of experiments were performed in an effort to demonstrate a role for plasma proteins in determining the amount of ivermectin available for transport across the blood-brain barrier of collie dogs sensitive to the effects of the compound. The solubility of ivermectin in plasma from non-sensitive and sensitive collies was measured and found to be identical at 100 g/ml. An assay for measuring the low affinity binding interaction of ivermectin with plasma components was developed. The amount of ivermectin bound per unit of plasma was the same for samples from sensitive and non-sensitive dogs. Dog serum albumin and the high density lipoprotein portion of the plasma were both capable of binding ivermectin. No differences in the binding characteristics of ivermectin in plasma from ivermectin sensitive and non-sensitive collies were found.     

Pharmacokinetics of extended-release ivermectin microspheres after oral administration to healthy pigs

We compared the pharmacokinetics of ivermectin premix and ivermectin microspheres in pigs after single and multiple administration regimes. In the single-dose experiments, 24 piglets were randomly divided into three groups and given ivermectin at 0.3 mg/kg using (a) 1.0% ivermectin administered subcutaneously, (b) 0.25% ivermectin premix orally, and (c) 0.25% ivermectin microspheres orally. In the multiple-dose experiment, 6 pigs in two equal groups received ivermectin premix and microspheres orally at 0.3 mg/kg for 7 consecutive days to monitor the valley plasma levels. The plasma samples were detected by fluorescence high-performance liquid chromatography, and concentration–time data were fitted to a noncompartmental model. After oral administration of ivermectin microspheres at a single dose, the elimination rate constant (Kel), the half-life (t_1/2), the peak time (T_max), the mean residence time (MRT), and the peak concentration (C_max) were 0.012 ± 0.0031/hr, 59.94 ± 20.18 hr, 9.50 ± 0.93 hr, 55.96 ± 11.40 hr, and 37.75 ± 3.45 ng/ml, respectively. The C_max of microspheres was not statistically different (p > .05) compared with that of premix groups (39.81 ± 5.83 ng/ml). Moreover, the AUC of the microcapsule groups was increased from 1,129.76 ± 245.62 to 1,607.33 ± 343.35 hr ng/ml compared with the premix groups, and the relative bioavailability increased by an average of 17.53% after oral administration with ivermectin microspheres. Multiple-dose administration also indicated pigs fed with ivermectin microspheres can get a higher minimum steady-state concentration and a longer maintenance time than ivermectin premix.     

米尔贝肟对自然感染疥螨病犬的治疗效果

为了评价米尔贝肟对临床自然感染疥螨犬的治疗效果,选用自然感染疥螨犬65例,随机选择5条服用伊维菌素,另外60条随机分为3组,分别服用高剂量(2g/kg体重)、中剂量(1g/kg体重)、低剂量(0.5g/kg体重)的米尔贝肟。给药后2、14、28、42d和56d,刮取皮屑,检查螨虫和虫卵,同时观察临床症状。试验结束时米尔贝肟高剂量组、伊维菌素组的无螨虫犬的比例和螨虫的下降率均为100%,临床症状如红疹、结痂、过度角化等现象均消失,所有动物毛发都开始大范围重生;米尔贝肟中、低剂量组结果稍差。米尔贝肟按2g/kg体重剂量,每周1次,连续用药3周,给药对自然感染疥螨病犬有很好的治疗效果。     

Efficacy of ivermectin in a controlled-release capsule for the control of breech strike in sheep

Objective To investigate the efficacy of ivermectin in an intraruminal controlled-release capsule (CRC) against blowfly strike.
Design Pen and field trials with controls.
Animals Pen studies: Two breech strike trials involving 60 Romney and 60 Merino sheep. One body strike trial using 100 Merino sheep.
Field trials: Eight trials in New Zealand used 1000 Romney and Romney-cross sheep. Fifty Merino lambs in one trial in Australia.
Procedure Pen studies: Sheep were allocated to two equal groups. One was not treated, the other sheep received a CRC that delivered ivermectin at 20 μg/kg/day for 100 days. In the breech strike trials, each animal was given an oral laxative 2 days before exposure to adult Lucilia cuprina . In the body-strike trial, the sheep sheep were kept wet to increase susceptibility prior to the release of blowflies.
Field trials: Fifty or 200 sheep allocated to equal groups of nontreated or treated with the CRC and grazed at pasture exposed to natural blowfly challenge.
Results Pen studies: Breech strikes developed in 24 of 60 controls but in none of 60 CRC-treated sheep. There was a 35% reduction in the number of CRC-treated sheep struck on the body.
Field trials: The average number of breech strikes in CRC-treated sheep was reduced by 86% (P < 0.001). The number of body strikes in the treated groups was a reduced by 27% (P < 0.05).
Conclusion The ivermectin CRC is a useful aid in controlling breech strike, but provides only moderate reduction in the incidence of body strike.     

Comparison of acetate tape impression with squeezing versus skin scraping for the diagnosis of canine demodicosis

This study compared the sensitivity of acetate tape impression and skin squeezing with that of deep skin scraping for the diagnosis of demodicosis in dogs. Demodex canis was detected in 100% of acetate tape impressions obtained after skin squeezing and in 90% of deep skin scrapings. There was a significant difference (P < 0.001) between the techniques in the total number of mites detected. Acetate tape impression with skin squeezing was found to be more sensitive than deep skin scraping and is an alternative diagnostic method for canine demodicosis.     

Efficacy of a topical antimicrobial-anti-inflammatory combination in the treatment of pyotraumatic dermatitis in dogs

Abstract The efficacy of a topical antimicrobial-corticosteroid combination for the treatment of pyotraumatic dermatitis in dogs, was investigated. An open-ended, double-blind, randomized trial design was used. Forty dogs were divided into two vehicle-treated control groups and three treatment groups. The dogs in the respective treatment groups were treated with emulsions of either neomycin, prednisolone or a neomycin-prednisolone combination. Lesions were shaved and cleaned before treatment commenced, whereafter the allocated emulsion was applied twice daily for 7 days. Lesions were evaluated for surface area and degree of pruritus and inflammation. Skin biopsy specimens for bacterial culture and histopathological examination were taken. Staphylococcus aureus was the predominant organism isolated. The antimicrobial-corticosteroid combination emulsion resulted in the quickest recovery, followed by the antimicrobial drug alone. Prednisolone alone gave significantly poorer results. Dogs in all groups, including the control groups, recovered completely within 7 days. Résumé L'efficacité d'un topique associant antimicrobien et corticoide dans le traitement de la dematite pyotraumatique du chien a étéétudiée. Une étude randomisée, ouverte, en double aveugle, a été réalisée. Quarante chiens ont été divisés en deux groupes controles traités seulement à l'aide du véhicule et trois groupes traités respectivement soit par l'émulsion de néomycine seule, de prednisolone seule ou par l'association néomycine-prednisolone. Les lésions ont été tondues et nettoyées avant la mise en place du traitement, après quoi l'émulsion a été appliquée deux fois par jour pour sept jours. Les lésions ont étéévaluées quant à leur extension et le degré de prurit et d'inflammation. Des biopsies cutanées ont été réalisées pour culture bactériologique et examen histopathologique. Le principal agent isolé est le staphyloccoque doré. L'émulsion associant antimicrobien et corticoide a entrainé la guérison la plus rapide, suivi par l'antimicrobien utilisé seul. La prednisolone utilisée seule a donné les plus mauvais résultats. Les chiens de tous les groupes, y compris les groupes controles, ont été complètement guéris en sept jours. [Schroeder, H., Swan, G. E., Berry, W. L., Pearson, J. Efficacy of a topical antimicrobial-anti-inflammatory combination in the treatment of pyotraumatic dermatitis in dogs (Efficatité d'un topique associant antimicrobien et antiinflammatoire dans le traitement de la dermatite pyotraumatique du chien). Veterinary Dermatology 1966; 7 : 163–170.] Résumén Se investigó la eficacia de un preparado tópico combinado antimicrobiano-corticoesteroideo en el tratamiento de la dermatitis piotraumática canina. Se utilizó un ensayo de final abierto, doble-ciego y al azar. Cuarenta perros se dividieron en dos grupos control tratados con un vehiculador y tres grupos a los que se aplicó el tratamiento. Los perros en los respectivos grupos de tratamiento fueron tratados con emulsiónes de en neomicina o prednisolona o con una combinación de neomicina-prednisolona. Se afeitaron y lavaron las lesiones antes del inicio del tratamiento, y después se aplicó la emulsión asignada dos veces al día durante 7 días. Se evaluaron las lesiones según el área afectada y el grado de prurito e inflamación. Se tomaron biopsias cutáneas para cultivo bacteriano y examen histopatológico. Staphylococcus aureus fue el organismo que predominó en los aislamiento. La emulsión con combinación de antibiótico-corticoesteroide fue la que cursó con una recuperación más rápida, seguido del antimicrobiano solo. El tratamiento unicamente con prednisolona dio resultados significativamente peores. Los perros de todos los grupos, incluyendo los de los grupos control, se recuperaron dentro de los 7 días de tratamiento. [Schroeder, H., Swan, G. E., Berry, W. L., Pearson, J. Efficacy of a topical antimicrobial-anti-inflammatory combination in the treatment of pyotraumatic dermatitis in dogs (Eficacia de un tratamiento antimicrobiano-antiinflamatorio topico combinado en la dermatitis piotraumatica canina). Veterinary Dermatology 1966; 7 : 163–170.] Zusammenfassung Die Wirksamkeit einer lokalen Antibiotikum-Kortikoid-Kombination für die Behandlung der pyotraumatischen Dermatitis des Hundes wurde untersucht. Es wurde das Modell einer offenen, randomisierten Doppelblindstudie verwendet. 40 Hunde wurden in zwei Vehikel-behandelte Kontroll-und drei Behandlungsgruppen eingeteilt. Die Hunde der drei Behandlungsgruppen wurden mit Emulsionen von Neomycin, Prednisolon oder einer Neomycin-Prednisolon-Kombination behandelt. Die Hautveränderungen wurden geschoren und gereinigt bevor die Behandlung begann. Dann wurde die entsprechende Emulsion zweimal täglich sieben Tage lang aufgetragen. Die Hautveränderungen wurden nach Größe der Oberfläche und Grad des Juckreizes und der Entzündung beurteilt. Es wurden Hautbioptate für bakteriologische Kulturen und histopathologische Untersuchungen entnommen. Als vorherrschender Keim wurde Staphylococcus aureus isoliert. Die Antibiotikum-Kortikoid-Kombination brachte die schnellste Abheilung, gefolgt von der ausschließlich antibiotischen Therapie. Prednisolon als Monotherapie ergab signifikant schlechtere Resultate. Die Hunde in alien Gruppen, einschließlich der Kontrollgruppen, gesundeten innerhalb von 7 Tagen vollständig. [Schroeder, H., Swan, G.E., Berry, W.L., Pearson, J. Efficacy of a topical antimicrobial-antiinflammatory combination in the treatment of pyotraumatic dermatitis in dogs (Wirksamkeit einer lokalen antimikrobiellen-entzündungshemmenden Kombination bei der Behandlung der pyotraumatischen Dermatitis des Hundes). Veterinary Dermatology 1996; 7 : 163–170.]