Sustained efficacy of collars containing 10% w/w imidacloprid and 4.5% w/w flumethrin (Seresto®) in dogs against laboratory challenge with Haemaphysalis longicornis (Neumann, 1901) ticks.

BACKGROUND: Haemaphysalis longicornis ticks are reported on dogs from an increasing geographic range. This study aimed to determine the sustained efficacy of Seresto® collars (imidacloprid/flumethrin) against experimental infestations of H. longicornis in dogs. METHODS: Twenty-four Beagle dogs previously assessed for their suitability to harbor ticks were included in the study and randomized into three groups of eight dogs each. Two of the groups were treated with collars at different time points: at the first tick infestation, dogs in group 1 had already worn collars for 92 days, while dogs in group 2 had received collars only on the previous day, thus allowing evaluation of two different treatment durations at the same point in time. Infestation of the treated groups was conducted at 1, 7, 28, and 56 days (group 2) and 92, 119, 147, 168, 196, 227, and 238 days (group 1) after collar placement. Group 3 served as untreated control and was infested whenever the dogs of the other two groups were infested. Infestations were conducted using 50 viable, adult, unfed female ticks of a US isolate of H. longicornis per dog. Ticks were removed and counted 48 h after each infestation. Health and body weight of the dogs were monitored throughout the study. The efficacy against ticks was calculated for groups 1 and 2 based on arithmetic mean values at each assessment day according to Abbott's formula. The mean post-treatment H. longicornis tick counts were compared statistically between treatments, using an analysis of variance with a treatment effect untransformed tick count. RESULTS: Dogs in the control group were adequately infested at all tick counts. Efficacy was 88.2% on day 3, however well above 90% (i.e., 98.3 to 100%) at all other time points up to day 240. Statistical analysis confirmed significantly different live tick counts (P < 0.001) between the treated groups and the control group at all time points. CONCLUSIONS: The 8-month sustained acaricidal efficacy demonstrated by the Seresto® collar (imidacloprid/flumethrin) provides a reliable strategy against H. longicornis infestations in dogs.

Molecular epidemiology and prevalence of babesial infections in dogs in two hyperendemic foci in Brazil.

Babesial parasites are some of the most ubiquitous blood pathogens and consequently have considerable worldwide veterinary impact. Dogs living in the tropics are highly exposed to babesial parasites, particularly to Babesia vogeli. Limited data on the seroprevalence and molecular prevalence of Babesia spp. in dogs are available in Latin America. We conducted a cross-sectional study combining serological and molecular tests to estimate the seroprevalence and molecular epidemiology of Babesia spp. infections in dogs in two hyperendemic foci in Brazil. A total of 630 privately owned dogs (417 from Goiana municipality, Pernambuco state, north-eastern Brazil, and 213 from São Joaquim de Bicas municipality, Minas Gerais state, south-eastern Brazil) were sampled and molecularly and serologically tested for Babesia spp. Overall, 519 dogs (82.4%) presented detectable IgG antibodies against Babesia spp., and seropositivity was significantly higher in dogs older than 1 year. Molecularly, 34 dogs (5.4%) were positive for a ~ 200 bp fragment of the 18S rRNA gene of Babesia spp. and 88 (14.0%) for a longer fragment (~ 450 bp) of the same gene of Babesia spp. and other protozoa. The 18S rRNA gene sequences generated herein corresponded to B. vogeli (n = 52) or Hepatozoon canis (n = 20). This study confirms a high level of exposure to B. vogeli in two areas of Brazil and highlights that most of the dogs living in these areas are infected during the course of their life, reflected by increased seroprevalence in older dogs. Increased awareness and prevention of tick-borne protozoa infections in dogs from Brazil and Latin America are urgently needed.

Prevalence and incidence of vector-borne pathogens in unprotected dogs in two Brazilian regions.

BACKGROUND: Various vector-borne pathogens (VBPs) affect dogs worldwide, with their diversity and force of infection being usually higher in the tropics. Cross-sectional studies have been conducted to investigate the prevalence of VBPs in dogs, but data from longitudinal studies are scarce. Herein, we assessed the prevalence and the year-crude incidence (YCI) of Leishmania spp. and other VBPs in privately-owned dogs from two geographical regions of Brazil. METHODS: A total of 823 dogs were initially screened for Leishmania spp. by both serology and polymerase chain reaction (PCR). From the negatives, 307 (103 from São Joaquim de Bicas, Minas Gerais, and 204 from Goiana, Pernambuco) were randomly selected for the longitudinal study. These dogs were tested for various VBPs at baseline, after 8 and 12 months. RESULTS: Out of 823 dogs initially screened, 131 (15.9%) were positive for Leishmania spp. Out of the 307 dogs enrolled in the longitudinal study, 120 (39.1%) were lost for different reasons (e.g. animal death, owner decision, and lost to follow-up). In São Joaquim de Bicas, the baseline prevalence and YCI were as follows: 16.5% and 7.1% for Anaplasma spp.; 81.6% and 100% for Babesia spp.; 0% and 1.3% (only one faint positive) for Dirofilaria immitis; 37.9% and 22.9% for Ehrlichia spp.; 19.5% and 43.8% for Leishmania spp. In Goiana, the baseline prevalence and YCI were as follows: 45.1% and 38.3% for Anaplasma spp.; 79.9% and 96.0% for Babesia spp.; 36.3% and 39.8% for D. immitis; 64.7% and 58.5% for Ehrlichia spp.; 14.7% and 19.6% for Leishmania spp. Anti-Borrelia burgdorferi antibodies were not detected in any of the samples tested herein. The prevalence and YCI of Anaplasma spp., D. immitis and Ehrlichia spp. were significantly higher in Goiana. In contrast, the YCI of Leishmania spp. infection was significantly higher in São Joaquim de Bicas. CONCLUSIONS: We confirmed a high prevalence and YCI of various VBPs among privately-owned dogs in two geographical regions of Brazil. Our data also indicate that the risk of infection varies significantly for individual VBPs and between the regions, which may be related to several factors that are still poorly understood.

W A A V P guideline for evaluating the efficacy of anticoccidials in mammals (pigs, dogs, cattle, sheep).

This guideline is intended as an aid in the design, implementation and interpretation of studies for the assessment of drug efficacy against Eimeria in cattle and sheep, Cystoisospora in pigs and dogs, and Cryptosporidium in cattle. It deals with the most important aspects of how to conduct both experimental and field studies for dose determination, dose confirmation and assessment of field effectiveness. Also, guidance on the selection of animals, diagnostic techniques, statistical evaluation and methods for the preparation, maintenance and use of parasites is provided. The specific management conditions that may influence the course of natural infections and consequently determine treatment schemes are mentioned and suggestions for best practice in sampling and evaluation of data prior to conducting of efficacy studies are given. The guideline is also intended to assist investigators in carrying out specific studies, provide relevant information for registration authorities involved in the decision-making process, assist in the approval of anticoccidial drugs in the target species, and facilitate the world-wide adoption of standard procedures. Although currently not implemented, issues of drug resistance testing and alternative methods for drug testing are also discussed as future issues in drug testing against mammalian coccidia.

Efficacy of emodepside plus toltrazuril oral suspension for dogs (Procox®, Bayer) against Trichuris vulpis in naturally infected dogs.

The efficacy of emodepside plus toltrazuril oral suspension for dogs (Procox®, Bayer) against Trichuris vulpis was evaluated in a controlled, blinded and randomised laboratory study. Twenty naturally infected dogs were included. Dogs in the treatment group received the minimum therapeutic dose of 0.45 mg emodepside and 9 mg toltrazuril per kg body weight, while dogs in the control group were left untreated. Efficacy was calculated based on worm counts after necropsy on Day 7 post treatment. Additionally, all faeces were collected and examined for expelled worms. The treatment was 100 % effective. A total of 233 adult worms (geometric mean 17.0) and 3 immature adult worms were found in the control group at necropsy. Adequacy of infection was demonstrated. The treated group excreted a total of 186 adult worms within 2 days after treatment. Additionally, all dogs were co-infected with Uncinaria stenocephala. Efficacy against this parasite was 99.8 %. No side effects of the treatment were observed. This study demonstrates that in addition to the formerly proven efficacy against Toxocara canis, Ancylostoma caninum and Uncinaria stenocephala, emodepside plus toltrazuril suspension is also effective against T. vulpis and thus represents a convenient treatment option for dogs co-infected with whipworms and coccidia.

Efficacy of emodepside plus toltrazuril (Procox(®) oral suspension for dogs) against Toxocara canis, Uncinaria stenocephala and Ancylostoma caninum in dogs.

The efficacy of emodepside plus toltrazuril (Procox® oral suspension for dogs) against different species of gastrointestinal nematodes (Toxocara canis, Ancylostoma caninum, Uncinaria stenocephala) was evaluated in nine randomised,blinded and placebo-controlled laboratory studies in naturally or experimentally infected dogs. The product was used at the proposed minimum dose of 0.45 mg emodepside and 9 mg toltrazuril per kg body weight. Efficacy was calculated based on worm counts after necropsy. Worm burdens in the control dogs ranged between 0 and 409 worms of the respective stage for T. canis and between 4 and 655 worms for hookworms. The studies demonstrated 100 % efficacy of emodepside/toltrazuril suspension against mature adult, ≥ 94.7 %efficacy against immature adult and 99.3 % efficacy against the L4 larval stage of T. canis. The efficacy against mature adult A. caninum was ≥ 99.5 % and the efficacy against mature adult U. stenocephala was 100 %. All differences between treatment and control groups were statistically significant and no gender effect was found. It can be concluded that the emodepside/toltrazuril suspension represents a safe and highly effective product in dogs with nematode (T. canis, hookworms) infection.

Efficacy of emodepside plus toltrazuril suspension (Procox(®) oral suspension for dogs) against prepatent and patent infection with Isospora canis and Isospora ohioensis-complex in dogs.

Three randomised, blinded and placebo-controlled laboratory studies were conducted to evaluate the efficacy of emodepside plus toltrazuril suspension (Procox(®) suspension for dogs) against Isospora canis and Isospora ohioensis-complex. Unweaned puppies were experimentally infected with sporulated oocysts of I. canis and/or I. ohioensis-complex. In each study, one group was treated during prepatency (2 or 4 days post infection) while dogs in the second group were treated individually after the onset of oocyst excretion of the respective coccidia species. The dogs were treated with the minimum therapeutic dose of 0.45 mg emodepside and 9 mg toltrazuril per kg body weight. Daily faecal oocyst counts from both groups were compared to placebotreated control groups to determine efficacy.Dogs treated during prepatent I. canis or I. ohioensis-complex infection showed significantly lower oocyst counts for up to 12 days compared to the control group. Oocyst counts were reduced by 90.2 - 100 % while the control groups continued to exhibit an adequate infection, except for one study where efficacy against prepatent I. canis infection faded 13 days after treatment. Following treatment of patent I. canis or I. ohioensis-complex infections, significantly lowered oocyst counts were observed for up to 9 days compared to the control group. Faecal oocyst counts were reduced by 91.5 - 100 %. In all three studies the number of days with diarrhoea was significantly lower when dogs were treated during prepatent Isospora spp. infection compared to the control groups. No adverse drug reactions were observed during the studies. In conclusion, the studies demonstrated that emodepside plus toltrazuril suspension is an efficient coccidiocide for dogs.

Field evaluations of the efficacy and safety of Emodepside plus toltrazuril (Procox® oral suspension for dogs) against naturally acquired nematode and Isospora spp. infections in dogs.

Three controlled, blinded and randomised multicentre field studies evaluated the efficacy and safety of a new formulation containing emodepside plus toltrazuril (Procox® suspension for dogs) against naturally acquired parasite infections in dogs. In two studies dogs positive for gastrointestinal nematodes and/or Isospora spp. were treated with emodepside/toltrazuril suspension (at least 0.45 mg emodepside plus 9 mg toltrazuril per kg body weight) or a reference product containing either milbemycin oxime plus praziquantel (Milbemax®) or sulfadimethoxine (Kokzidiol SD®) at recommended dose rates. The third study investigated efficacy against prepatent natural Isospora spp. infections in comparison to an untreated control group by enrolling Isospora- negative dogs that were at risk to develop a patent infection during the study.No suspected adverse drug reactions were observed in any of the 403 dogs enrolled in the three studies including 234 dogs treated with emodepside/toltrazuril suspension. In dogs treated with emodepside/toltrazuril suspension against nematode infection faecal egg counts were reduced by 100 % (reference product: 99.7 %). Similarly, in the dogs that had been treated against patent Isospora spp. infection, faecal oocyst counts were reduced by 100 % (reference product: 99.0 %). In both studies, statistical analysis demonstrated non-inferiority and even superiority to the reference products (p ≤ 0.009). Dogs treated with emodepside/toltrazuril suspension during suspected prepatent Isospora spp. infection had 98.7 % lower faecal oocyst counts after treatment compared to untreated dogs (p < 0.0001).The studies demonstrated that emodepside/toltrazuril suspension is safe and highly efficacious against nematodes and Isospora spp. under field conditions.

Efficacy of emodepside plus praziquantel tablets (Profender tablets for dogs) against mature and immature adult Ancylostoma caninum and Uncinaria stenocephala infections in dogs.

This paper reports the efficacy of a novel flavoured tablet formulation of emodepside plus praziquantel (Profender tablets for dogs) against mature and immature adult hookworms (Ancylostoma caninum and Uncinaria stenocephala) in dogs. The tablets were used at the minimum recommended dose of 1 mg emodepside and 5 mg praziquantel per kg body weight. Four randomised, blinded and controlled laboratory studies demonstrated >95% efficacy against mature and immature adult stages of U. stenocephala and four randomised, blinded and controlled laboratory studies demonstrated >98% efficacy against mature and immature adult stages of A. caninum. No side effects of the treatment were observed. It is concluded that the emodepside plus praziquantel tablet is an effective and safe treatment against mature and immature hookworms.

Efficacy of emodepside plus praziquantel tablets (Profender tablets for dogs) against mature and immature infections with Toxocara canis and Toxascaris leonina in dogs.

The efficacy of emodepside plus praziquantel tablets (Profender tablets for dogs) against mature adult, immature adult and larval stages of Toxocara canis and Toxascaris leonina was evaluated in ten randomised, blinded and placebo-controlled dose confirmation studies in naturally or experimentally infected dogs. The tablets were used at the proposed minimum dose of 1 mg emodepside and 5 mg praziquantel per kg body weight. Efficacy was calculated based on worm counts after necropsy. Five studies demonstrated >99% efficacy against mature adult, >92% efficacy against immature adult, >98% efficacy against L4 and >94% efficacy against L3 larval stages of T. canis. Another five studies demonstrated >99% efficacy against mature and immature adult and >95% efficacy against L4 larval stages of T. leonina. No side effects of the treatment were observed. Emodepside plus praziquantel tablets thus provide a comprehensive new treatment option for ascarid infections in the dog.

Efficacy of emodepside plus praziquantel tablets (Profender tablets for dogs) against mature and immature adult Trichuris vulpis infections in dogs.

This paper reports on the efficacy of a novel flavoured tablet formulation of emodepside plus praziquantel (Profender tablets for dogs) against mature and immature adult whipworms (Trichuris vulpis) at the proposed minimum dose of 1 mg emodepside and 5 mg praziquantel per kg body weight in dogs. Three randomised, blinded and controlled laboratory studies with naturally or experimentally infected dogs were performed. The first study was conducted as a dose determination study in experimentally infected dogs using three different dose levels, i.e., 0.5x, 1x and 2x the minimum therapeutic dose. Two further studies confirmed the efficacy of emodepside plus praziquantel tablets against mature and immature adult T. vulpis at the recommended minimum dose. In all three studies, the efficacy against mature and immature adult T. vulpis was >99%. No side effects of the treatment were observed. It is concluded that the emodepside plus praziquantel tablet is an effective and safe treatment against mature and immature adult stages of T. vulpis in dogs.

Efficacy of emodepside plus praziquantel tablets (Profender tablets for dogs) against mature and immature cestode infections in dogs.

The efficacy of a novel flavoured tablet formulation of emodepside plus praziquantel (Profender tablets for dogs) against intestinal cestodes was investigated in four randomised, blinded placebo-controlled dose confirmation studies in dogs experimentally infected with Echinococcus granulosus or E. multilocularis and in dogs naturally infected with Dipylidium caninum or Taenia spp. The tablets were used at the minimum recommended dose of 1 mg emodepside and 5 mg praziquantel per kg body weight. The studies demonstrated 100% efficacy against mature and immature E. granulosus and E. multilocularis and mature Taenia spp. and D. caninum. Additionally, one of the studies demonstrated non-interference of emodepside with the efficacy of praziquantel against D. caninum. No side effects of the treatment were observed. It is concluded that emodepside plus praziquantel tablets are safe and effective against mature and immature stages of E. granulosus and E. multilocularis and mature stages of Taenia spp. and D. caninum.

Field evaluation of the efficacy and safety of emodepside plus praziquantel tablets (Profender tablets for dogs) against naturally acquired nematode and cestode infections in dogs.

A controlled, blinded and randomised multicentre field study evaluated the efficacy and safety of a new anthelmintic tablet formulation containing emodepside plus praziquantel (Profender tablets for dogs) in the treatment of gastrointestinal nematode and cestode infections in dogs in France, Germany, Portugal and Slovakia. Dogs positive for nematodes and/or cestodes (demonstrated by faecal egg counts and/or the presence of proglottids) were treated with emodepside plus praziquantel tablets (n = 239) or the reference product containing milbemycin oxime and praziquantel (Milbemax [n = 115]) at the recommended dose rate. Two faecal samples collected between 7 and 13 days after treatment were evaluated for proglottids, nematode and cestode eggs. No suspected adverse drug reactions were observed in the study. The following parasite species were identified: Trichuris vulpis, Toxocara canis, Toxascaris leonina, Uncinaria stenocephala, Ancylostoma caninum, Dipylidium caninum, Taeniidae and Mesocestoides spp. Geometric mean nematode egg counts in dogs treated with emodepside plus praziquantel tablets were reduced by 99.9 % compared with a reduction of 99.6 % for the reference product. Statistical analysis demonstrated noninferiority of investigational versus reference product (p = 0.0342). None of the dogs treated with emodepside plus praziquantel or reference product remained positive for cestodes after treatment. The study demonstrated that emodepside plus praziquantel tablets are safe and highly efficacious against a broad spectrum of nematodes and cestodes under field conditions.