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Background: Infestation with Sarcoptes scabiei in dogs is a debilitating disease if left untreated and is transmissible to humans. Two field studies were conducted to confirm the efficacy of orally administered sarolaner in combination with moxidectin and pyrantel (Simparica Trio ® ) in the treatment of sarcoptic mange in dogs., Methods: Client-owned dogs with S. scabiei infestation were enrolled and received 2 monthly treatments. In the first, small-scale study, 12 dogs each were allocated randomly to treatment with either placebo or Simparica Trio ® . Skin scrapings to detect live mites and assessment of clinical signs of sarcoptic mange were conducted on Days 0, 14, 30, 44, and 60. Efficacy was calculated based on the percent reduction in arithmetic mean live mite counts relative to placebo. In the second, large-scale study, 75 dogs were allocated randomly to treatment with Simparica Trio ® and 37 to treatment with afoxolaner + milbemycin oxime (NexGard Spectra ® ). Skin scrapings to detect live mites and assessment of clinical signs of sarcoptic mange were conducted on Days 0, 14, 30, and 60. The parasitological cure rate (percentage of dogs without live mites) was determined and non-inferiority of Simparica Trio ® to the control product was assessed., Results: In the small-scale study, 2 monthly doses of Simparica Trio ® resulted in a significant reduction (P ≤ 0.0050) in live S. scabiei mite numbers and provided a 99.2% reduction relative to placebo by Day 60. Clinical signs of sarcoptic mange improved throughout the study in Simparica Trio ® -treated dogs. In the large-scale study, the parasitological cure rate on Days 30 and 60 was 97.3% and 100% in the Simparica Trio ® group and 91.9% and 100% in the afoxolaner + milbemycin oxime group, respectively. The parasitological cure rate for Simparica Trio ® was non-inferior to afoxolaner + milbemycin oxime at both time points. Clinical signs of sarcoptic mange improved throughout the study in both groups., Conclusions: Two-monthly doses of Simparica Trio ® reduced S. scabiei mite counts by 99.2% relative to placebo in one study and eliminated S. scabiei mites in 100% of dogs in the second study, thus confirming that Simparica Trio ® is highly effective in the treatment of sarcoptic mange in dogs caused by S. scabiei var. canis., (© 2023. The Author(s).)

Background: The parthenogenic reproductive ability of Haemaphysalis longicornis, facilitating quick life cycle completion and rapid geographic spread and its pathogen vector potential make infestations a risk to human and canine health. Two 90-day studies were initiated to evaluate the efficacy of a single fluralaner administration for the treatment and prevention of H. longicornis infestations on dogs., Methods: Dogs were randomly assigned (10 dogs/group) to either an untreated control group or a group treated once (Day 0) with 13.64% w/w fluralaner chewable tablets (Bravecto ® ) at the minimum label dose rate of 25 mg/kg. Each dog was infested with approximately 50 H. longicornis ticks on Days -9 or -6 and on Days -2, 28, 58 and 88. A different US tick isolate was used in each study. Tick counts were completed on Days -7 or -4, 2, 30, 60 and 90. The primary efficacy criterion was a 90% reduction in arithmetic mean tick counts between the treated and control groups. For between-group comparisons at any assessment, at least six control dogs were required to retain at least 25% of the infestation dose (13 live ticks)., Results: Pre-study infestations demonstrated susceptibility of all study dogs to challenge with H. longicornis. At each subsequent assessment in both studies, at least seven untreated control dogs retained ≥ 25% of the challenge, demonstrating adequate infestations for each efficacy calculation. On Days 2, 30, 60 and 90 the mean live tick infestation rate (number of ticks recovered from each dog/infesting challenge of each dog) of untreated control dogs ranged from 27.8 to 60.8%. No live ticks, free or attached, were found on any fluralaner-treated dog in either study. Between-group differences were statistically significant (P ≤ 0.0002) at each assessment., Conclusion: At the minimum recommended label dose rate of 25 mg/kg, fluralaner chewable tablets were 100% effective in eliminating H. longicornis ticks from dogs infested at the time of treatment. Complete efficacy against both US isolates of this tick was maintained through 90 days following a single treatment. Therefore, fluralaner is a treatment of choice for protecting dogs against this invasive tick species., (© 2023. The Author(s).)

Background: The invasive tick species, Haemaphysalis longicornis, is becoming established in the USA, presenting a growing threat to dogs and cats. Two 90-day studies were initiated, the same protocol in each, to confirm the efficacy of a single application of two fluralaner formulations against H. longicornis infestations of cats., Methods: Cats were randomized among three groups in a 1:1:1 ratio (10 cats/group). Group 1 cats were untreated controls; Group 2 cats were treated with a topical fluralaner formulation (Bravecto®); Group 3 cats received a topical formulation containing fluralaner and moxidectin (Bravecto® Plus). Treatments were administered once (Day 0) at the label dose rates. Each cat was infested with 50 H. longicornis ticks on Day 7 for study qualification and also infested with 50 ticks on Days 2, 28, 58 and 88. Tick counts were completed on Days 5, 2, 30, 60 and 90. The primary objective was based on percentage reductions in arithmetic mean tick counts., Results: Pre-study infestations showed all study cats were susceptible to tick challenge. Except for Day 2 in one study, at least six control cats retained ≥ 25% of each challenge, demonstrating an adequate infestation for efficacy assessments. Across studies on Days 2, 30, 60 and 90, the mean live tick infestation rate (number of ticks recovered from each cat/infesting challenge to each cat) of Group 1 cats ranged from 25.0 to 69.6%. Efficacy of each formulation, based on live tick counts, was 100% on Day 2 and > 95 to 100% at each subsequent assessment. Between-group differences were statistically significant (P < 0.0001) for each treatment versus control comparison., Conclusion: At the label dose rate, both topical fluralaner formulations were 100% effective in eliminating H. longicornis ticks from cats infested at the time of treatment. Efficacy of > 95 to 100% was then maintained through 90 days following a single application. Fluralaner is therefore a treatment of choice for protecting cats against this invasive tick species., (© 2023. The Author(s).)

Background: Tick infestations can cause direct deleterious effects to dogs as a result of tick blood-feeding, and indirectly ticks can transmit disease agents that can be detrimental to the health of both dogs and humans. Six laboratory studies were conducted to support dosage selection and efficacy confirmation of a novel combination of sarolaner, moxidectin and pyrantel against four tick species that commonly infest dogs in Europe., Methods: Two studies were conducted against Dermacentor reticulatus (one of which was a dose determination study), two against Ixodes ricinus, and one each against Ixodes hexagonus and Rhipicephalus sanguineus (sensu lato). In each study, eight purpose-bred Beagle or mix-breed dogs were randomly allocated to each treatment group and infested with 50 unfed adult ticks on Days-2, 5, 12, 19, 26 and 33. On Day 0 dogs were treated orally with placebo or the combination product. In the dose determination study, dogs received sarolaner at point dosages of 0.6 mg/kg, 1.2 mg/kg or 2.4 mg/kg in combination with moxidectin and pyrantel, and in all other studies dogs received Simparica Trio™ to provide minimum dosages of 1.2 mg/kg sarolaner, 24 µg/kg moxidectin and 5 mg/kg pyrantel (as pamoate salt). Efficacy was assessed based on live tick counts conducted 48 hours after treatment and each weekly infestation., Results: There were no treatment-related adverse events in any study. In the dose determination study, 1.2 mg/kg sarolaner was the lowest dosage evaluated that provided > 90% efficacy for at least 28 days and therefore was selected as the dosage to provide tick control for at least one month following a single oral treatment. In the dose confirmation studies, a single oral dose of Simparica Trio™ provided ≥ 99.2% efficacy against existing infestations of all tick species, and against re-infestations efficacy was ≥ 97.2% against D. reticulatus for 28 days and against all other species for 35 days., Conclusions: These studies support the sarolaner dose selected and confirm the efficacy of a single oral dose of Simparica Trio™ against existing infestations and re-infestations of the common tick species infesting dogs in Europe for at least one month.

Background: The southern African yellow dog tick, Haemaphysalis elliptica, occurs in eastern and southern Africa and adults infest domestic and wild carnivores. This tick species is also a vector of the highly virulent Babesia rossi pathogen, the causative agent of canine babesiosis in sub-Saharan Africa. Sustained high levels of efficacy of a parasiticide are not only important in protecting dogs against the direct effects of tick infestation, but also in reducing the risk of tick-borne diseases. Sarolaner (Simparica™ chewable tablets) has been reported to be effective against the major tick species infesting dogs in Europe and the USA, including representatives from the genera Amblyomma, Ixodes, Rhipicephalus and Dermacentor. Until now no efficacy evaluations have been reported against species of the genus Haemaphysalis. The objective of the study was to confirm the efficacy of a single 2 mg sarolaner/kg oral dose of Simparica™ against induced infestations with H. (R.) elliptica, an important parasite of dogs in southern Africa., Methods: This blinded, randomised, single centre, placebo controlled efficacy study followed a parallel group design and was conducted on two groups consisting of eight purpose-bred dogs each. Animals were treated orally, once on Day 0, with either a placebo compound (Group 1) or Simparica™ (Group 2). Simparica™ was administered orally at a dose rate of 2 mg sarolaner/kg body weight. The dogs were infested with ticks on Days - 7, - 2, 5, 12, 19, 26 and 33, with removal counts conducted on Days - 5, 2, 7, 14, 21, 28 and 35., Results: A single oral administration of Simparica™ (sarolaner) at a minimum dose of 2 mg/kg resulted in a 100% efficacy against existing infestations of H. (R.) elliptica on dogs and a 100% reduction in live ticks following weekly re-infestations for 35 days. Moreover, the immediate and persistent high levels of efficacy observed in this study for 35 days is consistent with those observed in previous studies against ticks in other genera., Conclusions: The efficacy of sarolaner (Simparica™), administered orally to dogs at the minimum label dose of 2.0 mg/kg, was demonstrated against existing and weekly re-infestations of H. (R.) elliptica for at least 5 weeks. Efficacy of 100% was achieved against existing infestations as well as weekly re-infestations.

Background: This study was designed to assess the ability of fed male Dermacentor reticulatus ticks to transmit Babesia canis to dogs after being detached from previous canine or ovine hosts., Methods: The study was an exploratory, parallel group design conducted in two trials. All the animals were sero-negative for babesiosis prior to enrolment. In a first trial, donor dogs and donor sheep were infested with Babesia canis infected male and uninfected female ticks for 72 h. The ticks were detached and the second group of host dogs were infested for 24 h before tick removal. In a second trial, the experiment was repeated but the donor animals were infested for 88 h and the second group of host dogs were infested for 8 h prior to tick removal. After infestation, the dogs were maintained under clinical surveillance and blood samples were collected for blood smear, IFA and PCR analysis. A dog was considered infected if any of these tests were positive., Results: All of the dogs (6 out of 6) were infected after being exposed to pre-activated male ticks for 24 h. Half of the dogs were infected after being exposed to pre-activated ticks for 8 h: 1 out of 3 dogs infested with ticks removed from sheep and 2 out of 3 dogs infested with ticks removed from dog. All the infected dogs were positive to blood smear, IFA and PCR. Three of these dogs exhibited elevated body temperature (> 39.4 °C)., Conclusions: This study demonstrates the ability of male D. reticulatus to transmit B. canis to dogs. The study also illustrates for the first time that, regardless of the first host on which ticks may attach and start feeding, Babesia canis can be transmitted to dogs within 8 h of infestation. Since no minimal transmission time can be established for all possible natural situations, a strategy of prevention based on anti-attachment or repellency is recommended.

Background: The oral systemic efficacy of lotilaner (Credelio™, Elanco) was evaluated against Demodex spp. in naturally infested dogs with generalized demodicosis., Methods: In this study, 10 dogs with clinical signs of generalized demodicosis and positive for Demodex spp. mites based on skin scrapings were assigned to a single group orally treated with lotilaner (minimum dose of 20 mg/kg) on Days 0, 28 and 56., Results: For lotilaner-treated dogs, pre-treatment mite counts based on skin scrapings performed at five different sites were reduced by > 99.9% (P < 0.0001) up to 56 days after the first and second monthly doses. No live mites were detected after Day 56 out to and including Day 84 post-treatment for 100% efficacy of each dog's Demodex mite infestation. Nine of 10 dogs were 100% mite-free from Day 28 (first evaluation) through Day 84 (end of study) and live mites were only found once on one dog (Day 56) following treatment with lotilaner. All dogs in the lotilaner-treated group showed marked improvement in the clinical signs of demodicosis and there were no drug associated adverse events. A marked improvement in hair re-growth was observed in all the dogs from 6 weeks following initiation of treatment., Conclusions: In this study lotilaner administered at a minimum oral dose of 20 mg/kg was highly effective in reducing and eliminating live mite counts in dogs with natural infestations of Demodex spp.

Background: Canine babesiosis is a clinically significant emerging vector-borne disease caused among others by the protozoan Babesia canis. The efficacy of sarolaner (Simparica®; Zoetis; at the minimum recommended label dose of 2.0 mg per kg bodyweight) in the prevention of babesiosis was evaluated in twenty-four dogs randomly allocated to either a placebo-treated group or one of two sarolaner-treated groups. At 21 or 28 days after treatment administration, dogs were infested with 50 ± 4 Dermacentor reticulatus ticks of which 25% were confirmed to be infected with Babesia canis. Blood samples were collected from each dog prior to tick infestation and weekly thereafter until 49 days after infestation. The blood was assayed for B. canis antibodies using an indirect immunofluorescence test (IFAT) and for B. canis DNA by PCR assay. A dog was a priori defined as B. canis-positive if it tested positive by both IFAT and PCR at any time during the study., Results: No treatment-related adverse reactions were recorded during the study. All placebo-treated animals displayed clinical signs due to babesiosis and tested positive on both IFAT and PCR. None of the sarolaner-treated animals displayed any clinical symptoms or tested positive on both IFAT and PCR, resulting in a 100% efficacy in the prevention of canine babesiosis (P = 0.0002)., Conclusion: When given 21 or 28 days before tick infestation, a single treatment with sarolaner at the minimum recommended label dose of 2.0 mg per kg body weight prevented the transmission of B. canis by D. reticulatus to dogs.

Background: The cat flea, Ctenocephalides felis felis (C. felis), is a cosmopolitan hematophagous ectoparasite, and is considered to be the most prevalent flea species in both Europe and the USA. Clinical signs frequently associated with flea bites include pruritus, dermatitis and in severe cases even pyodermatitis and alopecia. Ctenocephalides felis is also a vector for several pathogens and is an intermediate host for the cestode Dipylidium caninum. Treatment of cats with a fast-acting pulicide, that is persistently effective in protecting the animal against re-infestation, is therefore imperative to their health. In addition, a rapid onset of activity ("speed of kill") may also reduce the risks of disease transmission and flea allergic dermatitis. The aim of this study was to evaluate the in vitro insecticidal activity and potential synergism between dinotefuran and fipronil against C. felis. A further aim was to evaluate the onset of activity and residual speed of kill of the combination in vivo on cats artificially infested with C. felis., Methods: In the first study, the insecticidal activity of dinotefuran and fipronil separately and dinotefuran/fipronil (DF) in combination, at a fixed ratio (2:1), was evaluated using an in vitro coated-vial bioassay. In the second study, the onset of activity against existing flea infestations and residual speed of kill of DF against artificial flea infestations on cats was assessed in vivo. Onset of activity against existing flea infestations was assessed in terms of knock-down effect within 2 h post-treatment and onset of speed of kill assessed at 3 h, 6 h and 12 h post-treatment. Residual speed of kill was evaluated 6 h and 48 h after infestation, over a period of six weeks post-treatment., Results: In vitro results revealed that the DF combination was synergistic and more potent against fleas than either compound alone. The combination also proved effective when tested in vivo. Efficacy was > 97% [geometric mean (GM) and arithmetic mean (AM)] at 3 h after treatment, and ≥ 99.8% (GM and AM) at 6 h and 12 h post-treatment. At 6 h after flea re-infestations, the efficacy of DF remained ≥ 90.8% (GM and AM) for up to 28 days, and at 42 days post-treatment persistent efficacy was still ≥ 54.3% (GM and AM). At 48 h after flea re-infestations, DF remained almost fully effective for up to 28 days, with efficacies ≥ 99.4% (GM and AM) and was persistently ≥ 93.0% (GM and AM) effective for up to 42 days post-treatment., Conclusions: The combination of dinotefuran and fipronil in a single formulation exhibited strong synergistic insecticidal activity against C. felis in vitro, and also proved effective on artificially infested cats. This activity had a rapid onset that persisted for 6 weeks against re-infestations of C. felis on cats. The rapid curative insecticidal effect was observed as early as 3 h after treatment, and as early as 6 h after re-infestations for up to 6 weeks post-treatment. The insecticidal activity profile of DF makes it an optimal candidate for the protection of cats against flea infestations, and possibly also associated diseases.

Background: Ticks are increasingly reported on cats worldwide, with Ixodes ricinus being a relevant species across Europe and in near by areas of North Africa and the Middle East. Yet there are few acaracidal products with proven efficacy approved for use in cats. The objective of this study was to compare the efficacy of a new spot-on formulation containing selamectin and sarolaner with a topical application of fluralaner (Bravecto®) against Ixodes ricinus ticks on cats. To that end, twenty-four (24) cats were randomly allocated to one of three treatment groups. The cats in the control group remained untreated. Cats in group 2 were treated with selamectin/sarolaner (Stronghold®Plus; Zoetis) at the minimum recommended dose of 1.0 mg/kg sarolaner and 6.0 mg/kg selamectin on Days 0, 30 and 60. The cats in group 3 received a fluralaner treatment (Bravecto®spot-on solution for cats, MSD) at the minimum recommended dose of 40.0 mg/kg on Day 0. Cats were infested with 50 (± 4) viable, adult, unfed I. ricinus ticks on Days 26, 54, 82 and 89 and ticks were removed for counting 48 h (± 2 h) later., Results: Three monthly treatments with selamectin/sarolaner provided high and consistent efficacy against I. ricinus for the entire duration of the study period. In contrast, the efficacy of fluralaner declined in the second month after treatment and was below the efficacy threshold of 90% on Days 56, 84 and 91. The percentage efficacy against I. ricinus was numerically higher in the selemectin/sarolaner treated group than in the fluralaner-treated group on Days 56, 84 and 91. Furthermore, greasiness and spiking of the hair, as well as white deposits were frequently observed in the fluralaner-treated cats., Conclusion: The results of the present study confirm the high and consistent efficacy of a new spot-on combination product containing selamectin and sarolaner against I. ricinus in cats, and indicate a decline in fluralaner efficacy during the 91 day period after treatment.

Background: The efficacy of fluralaner, formulated as a chewable tablet (Bravecto™) or topical solution (Bravecto™ Spot-on Solution), was evaluated against naturally acquired Sarcoptes scabiei var. canis infestation in dogs., Methods: The study was performed in privately-owned dogs naturally infested with S. scabiei var. canis. All dogs living in the same household as the infested dog were enrolled into one of 3 groups (2 fluralaner treated and 1 negative control). All dogs within one household were administered the same treatment, with one dog per household included in further observations and assessments. In total, 29 dogs confirmed positive for sarcoptic mange were included. On Day 0, all dogs in group 1 (n = 9) were treated once orally with fluralaner at a minimum dose of 25 mg/kg body weight; all dogs in group 2 (n = 11) were treated once topically with fluralaner at a dose of 25 mg/kg body weight; and dogs in group 3 (n = 9) were treated once topically with saline solution. Sarcoptes scabiei var. canis mites on each dog were counted before treatment and at 4 weeks after treatment in deep skin scrapings (~4 cm(2)) from 5 different body areas. Clinical signs of infestation (i.e. erythematous papules; casts, scales and crusts; body areas with hair loss) and pruritus were recorded at the same time points., Results: Single oral or topical treatment with fluralaner resulted in a 100 % reduction in mite counts post-treatment (group 1: P = 0.0009 and group 2: P = 0.0011). Resolution of clinical signs at four weeks post-treatment was variable, with improvement observed for erythematous papules, casts and crusts, and pruritus. All fluralaner treated dogs showed an improvement in overall hair re-growth compared with pre-treatment observations., Conclusion: Fluralaner administered either orally or topically to naturally infested dogs eliminates Sarcoptes scabiei var. canis mites and improves clinical signs over a 4-week observation period.

Background: The preventive effect of fluralaner spot-on solution against transmission of Babesia canis by Dermacentor reticulatus ticks was evaluated., Findings: Sixteen dogs, tested negative for B. canis by polymerase chain reaction (PCR) and immunofluorescence assay test (IFAT), were allocated to two study groups. On day 0, dogs in one group (n = 8) were treated once topically with fluralaner spot-on solution (Bravecto™ Spot-on Solution) according to label recommendations and dogs in the control group (n = 8) remained untreated. On days 2, 28, 56, 70 and 84, all dogs were infested with 50 (±4) D. reticulatus ticks harbouring B. canis, with tick in situ thumb counts 48 ± 4 h after each infestation. On day 90, ticks were removed from all dogs and counted. Prior to each infestation, the presence of B. canis in the respective tick batch was confirmed by PCR, and 12-16 % of ticks were found to be infected with B. canis. Efficacy against ticks was 99.5 and 99.3 % on days 4 and 58 after treatment, respectively and 100 % on all other days. Replacement dogs were included for any B. canis infected control dog (in total 19). All control dogs (n = 27) became infected with B. canis, as confirmed by PCR, performed every 7 days, and by IFAT, performed every 14 days after treatment. None of the eight treated dogs became infected with B. canis, as they were tested negative by PCR and IFAT throughout the study until day 112. By comparing infected dogs in the treated group with infected dogs in the untreated control group, a 100 % preventive effect against B. canis transmission was demonstrated., Conclusions: A single topical administration of fluralaner spot-on solution effectively prevented the transmission of B. canis by infected D. reticulatus ticks over a 12-week period.

Background: The efficacy of fluralaner spot-on solution administered once topically against induced infestations with Rhipicephalus sanguineus was evaluated in dogs over a 12-week post-treatment period., Methods: Six negative-controlled studies were conducted, involving a total of 112 adult dogs (57 mixed breed, 47 Beagles, eight Labradors). In each study, dogs were randomized to two groups of eight to ten dogs each. On day 0, dogs in each treated group were topically administered fluralaner spot-on solution once at a dose of 25 mg/kg body weight, while dogs in each control group were not treated. Two days before treatment, and on days 28, 56 and 84 after treatment, all dogs were infested with approximately 50 unfed, adult Rh. sanguineus ticks (sex ratio 1:1). Ticks were removed and counted on days 2, 30 (4 weeks), 58 (8 weeks), and 86 (12 weeks) after treatment to assess efficacy., Results: Efficacy against ticks 2 days after treatment was 91.1 % (study 1), 98.4 % (study 2), 100 % (study 3), 97.6 % (study 4), 99.6 % (study 5), and 99.8 % (study 6). At all other assessment time points, tick efficacy was 95.4-100 %. Tick reduction in all treatment groups was significant at all assessment time points (P < 0.0001)., Conclusions: A single topical administration of fluralaner spot-on solution provides a high level of therapeutic and persistent efficacy against Rh. sanguineus ticks over the subsequent 12 weeks.

Background: Rhipicephalus sanguineus is the most widely distributed tick species infesting dogs worldwide, which may cause discomfort to the host and transmit diseases. Acaricides with a rapid and sustained speed of kill are thus important to prevent infestation and to reduce the risk of disease transmission. In this study, the speed of kill of a monthly administered Simparica™ (sarolaner) treatment against induced infestations with R. sanguineus on dogs was evaluated and compared with a single dose of Bravecto®(fluralaner) for 95 days after the initial treatment., Methods: Twenty four dogs were randomly allocated to treatment and were treated with either placebo or sarolaner (at 2 to 4 mg/kg) on Days 0, 30 and 60 or with fluralaner (at 25 to 56 mg/kg) once on Day 0. Tick counts were performed in situ 8 and 12 h and with removal of the ticks 24 h after treatment and subsequent re-infestations on Days 14, 28, 44, 56, 74, 90 and 95. Acaricidal efficacy was determined at each time point relative to the placebo group., Results: Both products significantly reduced live ticks within 8 h after treatment against an existing infestation with R. sanguineus, and killed all ticks on all dogs within 24 h. After re-infestation, sarolaner provided ≥98.5 % reduction within 24 h on all days except Days 74 and 95 (P < 0.0001), compared to fluralaner which provided ≥95.5 % reduction until Day 44. Geometric mean live tick counts for sarolaner were significantly lower (P ≤ 0.0415) at 24 h than those for fluralaner on all days, except on Days 0, 14 and 28 (P ≥ 0.0678). There were no treatment-related adverse reactions observed during the study., Conclusions: When dosed at monthly intervals for 3 consecutive months, Simparica™ has a faster and more consistent speed of kill against R. sanguineus than a single oral dose of Bravecto® for which efficacy decreased after Day 44.

Background: Fleas are the most common ectoparasite infesting dogs globally and cause direct discomfort, induce allergic reactions, and transmit pathogenic agents. Rapid speed of kill is an important characteristic for a parasiticide in order to alleviate the direct deleterious effects of fleas, reduce the impact of allergic responses, and break the flea life cycle. In this study, the speed of kill of a novel, orally administered isoxazoline parasiticide, sarolaner (Simparica), against fleas on dogs was evaluated and compared with fluralaner (Bravecto) over a 3-month period., Methods: Based on pretreatment flea counts, 24 dogs were randomly allocated to treatment with oral sarolaner at the label rate (2 to 4 mg/kg), once a month for 3 months, or oral fluralaner (25 to 50 mg/kg), once per label directions, or placebo. Dogs were combed and live fleas counted at 8, 12, and 24 h after treatment and subsequent re-infestations on Days 14, 29, 44, 59, 74 and 90. Efficacy was determined at each time point relative to counts for placebo dogs., Results: There were no adverse reactions to treatment. Three monthly doses of sarolaner provided ≥97.6 % efficacy (based on arithmetic means) within 8 h of treatment or subsequent weekly re-infestations of fleas for 3 months. By 12 h, fleas were eradicated from all dogs (100 % efficacy). Significantly greater numbers of live fleas were recovered from fluralaner-treated dogs at 8 h on Days 74 and 90 (P ≤ 0.0043) when efficacy (based on arithmetic means) was only 80.7 and 72.6 %, respectively., Conclusions: In this controlled laboratory evaluation, sarolaner had a significantly faster speed of kill against fleas than fluralaner at the end of its claimed treatment period. The rapid and consistent kill of fleas within 8 to 12 h after monthly oral doses of sarolaner indicates that this treatment will provide rapid and highly effective control of flea infestations, and suggests that it will provide relief for dogs suffering from flea allergy dermatitis, and should reduce the risk of flea-borne pathogen transmission.

Background: Fleas are the most common ectoparasite infesting dogs globally. The many possible sequellae of infestation include: direct discomfort; allergic reactions; and the transmission of pathogens. Rapid speed of kill is an important characteristic for a parasiticide in order to alleviate the direct deleterious effects of fleas, reduce the impact of allergic responses, and break the flea infestation cycle. In this study, the speed of kill of a novel orally administered isoxazoline parasiticide, sarolaner (Simparica) against fleas on dogs was evaluated and compared with afoxolaner (NexGard) for 5 weeks after a single oral dose., Methods: Twenty-four dogs were randomly allocated to treatment with a single oral dose at label rate of either sarolaner (2 to 4 mg/kg) or afoxolaner (2.5 to 6.8 mg/kg) or placebo, based on pretreatment flea counts. Dogs were combed and live fleas counted at 8, 12 and 24 h after treatment and subsequent re-infestations on Days 7, 14, 21, 28 and 35. Efficacy was determined at each time point relative to counts for placebo dogs., Results: There were no adverse reactions to treatment. A single oral dose of sarolaner provided ≥98.8% efficacy (based on geometric means) within 8 h of treatment or subsequent weekly re-infestations of fleas to Day 35. By 12 h, fleas were virtually eradicated from all dogs, with only two fleas recovered from a single sarolaner-treated dog on Day 7; efficacy was 100% at all other time points. Significantly greater numbers of live fleas were recovered from afoxolaner-treated dogs at 8 h on all days and at 12 h on Days 28 and 35 (P < 0.05)., Conclusions: In this controlled laboratory evaluation, sarolaner had a significantly faster speed of kill against fleas than afoxolaner. This was noticeably more evident towards the end of the treatment period. The rapid and consistent kill of fleas within 8 to 12 h after a single oral dose of sarolaner over 35 days indicates that this treatment will provide highly effective control of flea infestations, relief for dogs afflicted with flea allergy dermatitis, and should reduce the risk of flea-borne pathogen transmission.

Background: A blinded, controlled laboratory study was conducted to assess the repellency and acaricidal activity of a topical spot on formulation, a combination of fipronil and permethrin, against Ixodes ricinus and Rhipicephalus sanguineus ticks on dogs., Methods: A group of 16 adult mixed breed dogs were randomly divided into treatment and control groups based on pre-treatment live tick counts. On Day 0, the topical spot on formulation of fipronil + permethrin (commercialized under the name Frontline Tri-Act®/Frontect®) was administered to dogs in the treatment group at the minimum recommended dose of 0.1 mL/kg, corresponding to 6.76 mg fipronil/kg and 50.48 mg/kg permethrin. Tick infestations were performed with I. ricinus (50 females, 50 males) and R. sanguineus (25 females, 25 males) on each dog on Days 2, 7, 14, 21, and 28. Dogs were sedated prior to exposure and confined to crates for approximately 4 h following tick challenge. Ticks were released next to the sedated dogs and tick counts were performed at 4 h and 24 h after the start of exposure for tick counts and removal., Results: Repellency at 4 h against I. ricinus was 72.6, 96.3, 92.8, 89.0, and 88.7 % on Days 2, 7, 14, 21, and 28, respectively. Repellency was 100 % 24 h after exposures on Days 2, 7, and 14 and 99.6 % after exposures on Days 21 and 28. For R. sanguineus, repellency at 4 h was 78.0, 96.8, 91.5, 88.0, and 56.8 % on Days 2, 7, 14, 21, and 28, respectively. Repellency at 24 h was 98.6, 100, 98.7, 96.1, and 95.1 % for exposures on Days 2, 7, 14, 21, and 28, respectively. For I. ricinus, acaricidal efficacy recorded at 4 h was ≥ 91.1 % during the full month and was ≥ 99.5 % for the full month when counted at 24 h. Acaricidal efficacy against R. sanguineus was ≥ 94.7 % at 4 h from Day 2 to Day 21 and was 71.4 % on Day 28. Acaricidal efficacy at 24 h, was > 97.7 % during the month. Tick counts were statistically significantly reduced in treated dogs at all time-points during the study., Conclusions: A combination of fipronil and permethrin was highly effective at rapidly repelling and killing both I. ricinus and R. sanguineus ticks on dogs for at least 4 weeks, with a significant effect at 4 and 24 h after tick exposure.

Background: The preventive effect of fluralaner chewable tablets (Bravecto™) against transmission of Babesia canis by Dermacentor reticulatus ticks was evaluated., Methods: Sixteen dogs, tested negative for B. canis by PCR and IFAT, were allocated to two study groups. On day 0, dogs in one group (n = 8) were treated once orally with a fluralaner chewable tablet according to label recommendations and dogs in the control group (n = 8) remained untreated. On days 2, 28, 56, 70 and 84, dogs were infested with 50 (±4) B. canis infected D. reticulatus ticks with tick in situ thumb counts 48 ± 4 h post-infestation. Prior to each infestation, the D. reticulatus ticks were confirmed to harbour B. canis by PCR analysis. On day 90, ticks were counted and removed from all dogs. Efficacy against ticks was calculated for each assessment time point. After treatment, all dogs were physically examined in conjunction with blood collection for PCR every 7 days, blood samples for IFAT were collected every 14 days and the dog's rectal body temperature was measured thrice weekly. From dogs displaying symptoms of babesiosis or were PCR positive, a blood smear was taken, and, if positive, dogs were rescue treated and replaced with a replacement dog. The preventive effect was evaluated by comparing infected dogs in the treated group with infected dogs in the untreated control group., Results: All control dogs became infected with B. canis, as confirmed by PCR and IFAT. None of the 8 treated dogs became infected with B. canis, as IFAT and PCR were negative throughout the study until day 112. Fluralaner chewable tablet was 100 % effective against ticks on days 4, 30, 58, and 90 and an efficacy of 99.6 % and 99.2 % was achieved on day 72 and day 86 after treatment, respectively. Over the 12-week study duration, a 100 % preventive effect against B. canis transmission was demonstrated., Conclusions: A single oral administration of fluralaner chewable tablets effectively prevented the transmission of B. canis by infected D. reticulatus ticks over a 12-week period.

Background: This laboratory study compared the efficacy of Bravecto™ (fluralaner), formulated as a chewable tablet, with the efficacy of Advocate® (imidacloprid/moxidectin), formulated for topical administration, against naturally acquired generalized demodicosis in dogs., Methods: Sixteen dogs, all diagnosed with generalized demodectic mange, were randomly allocated to two equal groups. Bravecto™ chewable tablets were administered once orally at a minimum dose of 25 mg fluralaner/kg body weight to one group of dogs, while the second group was treated topically on three occasions at 28-day intervals with Advocate® at a minimum dose of 10 mg imidacloprid/kg body weight and 2.5 mg moxidectin/kg body weight. Mites were counted in skin scrapings and demodectic lesions were evaluated on each dog before treatment and at 28-day intervals thereafter over a 12 week study period. Deep skin scrapings (~4 cm(2)) were made from the same five sites on each dog at each subsequent examination., Results: After single oral administration of Bravecto™ chewable tablets, mite numbers in skin scrapings were reduced by 99.8% on Day 28 and by 100% on Days 56 and 84. Mite numbers in the dogs treated topically on three occasions at 28-day intervals with Advocate® were reduced by 98.0% on Day 28, by 96.5% on Day 56 and by 94.7% on Day 84. Statistically significantly (P ≤ 0.05) fewer mites were found on Days 56 and 84 on the Bravecto™ treated dogs compared to Advocate® treated dogs. A marked decrease was observed in the occurrence of erythematous patches, crusts, casts and scales in the dogs treated with Bravecto™ and in the occurrence of erythematous patches in the dogs treated with Advocate®. With the exception of one dog in each treated group, all dogs exhibited hair regrowth ≥ 90% at the end of the study in comparison with their hair-coat at study start., Conclusions: Single oral administration of Bravecto™ chewable tablets is highly effective against generalized demodicosis, with no mites detectable at 56 and 84 days following treatment. In comparison, Advocate®, administered three times at 28-day intervals, is also highly effective against generalized demodicosis, but most dogs still harboured mites at all assessment time points. Both treatments resulted in a marked reduction of skin lesions and increase of hair re-growth 12 weeks after the initial treatment.