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Parasitic respiratory infections in domestic sheep and goats are caused by Dictyocaulus filaria and various species belonging to the Protostrongylidae family of nematodes which frequently occur in mixed infections. Although the parasitism with protostrongylid lungworms is generally considered to be of low pathogenicity, there are reports of clinical disease including cases associated with Protostrongylus rufescens infection. The efficacy against P. rufescens of eprinomectin 5 mg/mL topical solution (EPRINEX® Multi, Boehringer Ingelheim) was thus evaluated in a clinical study compliant with GCP and VICH anthelmintic efficacy testing guidelines in adult sheep with naturally acquired infection. Following ranking on pre-treatment Protostrongylus fecal larval counts and forming into blocks of two animals, the sheep were randomly allocated to either remain untreated (control) or to be administered eprinomectin 5 mg/mL topical solution at 1 mL/5 kg body weight (equivalent to 1 mg eprinomectin per kg body weight) once as a pour-on. Fecal samples of the sheep were examined to monitor the larval excretion weekly for five weeks after treatment; then the animals were necropsied for lungworm recovery and count to determine the efficacy of the treatment. After treatment, Protostrongylus larval excretion decreased to zero within three weeks. Nematode counts demonstrated that the efficacy of the treatment with eprinomectin 5 mg/mL topical solution was 100 % against P. rufescens: no lungworms were recovered from any treated sheep while all controls harbored P. rufescens (range, 17-406) (p < 0.001). The treatment was well accepted; no treatment-related health problems were observed., (Copyright © 2021 Elsevier B.V. All rights reserved.)

The efficacy of the eprinomectin, praziquantel, fipronil and (S)-methoprene combination parasiticide Broadline® (Boehringer Ingelheim Animal Health) was evaluated against developing larval and adult stages of Troglostrongylus brevior, a metastrongyloid pulmonary nematode which is reported to parasitize domestic cats in southern Europe with increasing frequency. Twenty four purpose-bred cats were experimentally infected with 100 third-stage T. brevior larvae each and randomly allocated to either remain untreated (control) or to be treated with the combination product when T. brevior were developing larval (6 days post inoculation, dpi) or adult nematodes (28 dpi) (eight cats per group). Treatments were administered topically at the minimum label dose of 0.12mL/kg. Fecal samples of the cats were examined to confirm the presence of patent (adult) nematode infections prior to treatment at 28 dpi and to monitor the larval excretion. At necropsy (49 dpi), the weight of the pulmonary lymph nodes and lungs were determined, and T. brevior lungworms were recovered and counted. All control animals and cats to be treated at 28 dpi excreted T. brevior larvae 24 dpi and 26 dpi while no larvae were excreted by the cats treated at 6 dpi. Following treatment at 28 dpi, T. brevior larval excretion decreased immediatetly and ceased prior to necropsy. Nematode counts demonstrated that treatment with the combination product was 100 % efficacious against both developing larval and adult T. brevior: no lungworms were recovered from any treated cat while all control animals harbored T. brevior (range, 6-52) (p<0.001). No treatment-related health problems or any other clinical signs were observed in the cats. However, significantly higher absolute and relative (organ weight to body weight ratio) pulmonary lymph node weights of the control animals compared with the treated cats at 6 dpi (p<0.001 and p<0.001, respectively) and at 28 dpi (p=0.003 and p=0.019, respectively) indicated the pathology of the T. brevior infection. In conclusion, the combination product was demonstrated to be 100 % efficacious against developing larval and adult T. brevior. Furthermore, it was demonstrated that indicators of impaired respiratory and immune systems resultant from T. brevior infection can be prevented with an efficacious treatment when administered during the pre-patent period of infection or are improving substantially within three weeks of treatment of cats harboring adult lungworms., (Copyright © 2020 The Authors. Published by Elsevier B.V. All rights reserved.)

Ancylostomaceylanicum hookworms parasitize dogs and cats in subtropical and tropical South East Asia and Pacific region, the Arab Peninsula, southern Africa and South America but cause patent infections in humans too. To evaluate the efficacy of Broadline®, a combination product comprising eprinomectin, fipronil, (S)-methoprene and praziquantel, against developing fourth-larval stage (L4) and adult A. ceylanicum in cats, a blinded, induced infection study was conducted. Following oral inoculation of 24 purpose bred cats with ˜300 infectious A. ceylanicum larvae each, cats were allocated to one of three groups of eight animals, each which served either as untreated controls or received Broadline® (once topically at the minimum label dose of 0.12mL per kg bodyweight) when the hookworms were L4 (five days post inoculation, dpi) or adults (25 dpi). Efficacy was determined on nematode counts following necropsy of the cats. Fecal examination at 22 dpi confirmed that all cats of the control group and of the group to be treated when the hookworms were adult were excreting hookworm eggs (range, 100 to 1000 eggs per gram) while no eggs were recovered from the feces of the cats treated with Broadline® 5 dpi. Nematode counts established 35 dpi demonstrated that Broadline® treatment was 100% efficacious against both, developing L4 and adult A. ceylanicum: no hookworms were recovered from any Broadline®-treated cat while all control animals harbored A. ceylanicum (range, 8-35) (p<0.001). No health problems were observed throughout the study., (Copyright © 2020 The Authors. Published by Elsevier B.V. All rights reserved.)

The present study was conducted to further characterize the anthelmintic activity of the 0.5% w/v topical formulation of eprinomectin (EPRINEX ® Pour-on, Merial) when administered at 1 mg/kg body weight to sheep in preventing the establishment of induced gastrointestinal and pulmonary nematode infections. Thirty-six female Merino sheep (∼4 months of age, weighing 27.0-36.0 kg) were blocked by pre-treatment body weight to form blocks of four animals. Within blocks, the animals were randomly allocated to either remain untreated (control) or be treated once with EPRINEX ® either on Day 0, Day 7 or Day 14. Starting on Day 15, the sheep were given trickle infections with infective larvae of seven species of gastrointestinal nematodes and Dictyocaulus filaria lungworms daily for seven consecutive days. Five weeks after completion of the daily challenge (Day 56), the animals were necropsied for parasite recovery and count. Treatment with EPRINEX ® prevented the establishment (>90%, p ≤ 0.027) of D. filaria, Teladorsagia circumcincta (pinnata/trifurcata), Cooperia curticei, Nematodirus battus, Trichostrongylus colubriformis and Oesophagostomum venulosum for at least 21 days, and of Haemonchus contortus and Trichostrongylus axei for at least 14 days. Sheep in the groups treated with EPRINEX ® at Days 7 and 14 had significantly (p ≤ 0.018) higher Day -1 to Day 56 wt gains than the untreated controls. No treatment-related health problems or any other health problems were observed throughout the study., (Copyright © 2018 Elsevier B.V. All rights reserved.)

The efficacy of oral afoxolaner plus milbemycin oxime combination chewable tablets (NexGard Spectra, Merial) against naturally acquired intestinal nematode infections in dogs was evaluated in six negative control, blinded studies including a total of 114 dogs. Dogs were selected based on a pre-treatment fecal examination indicating patent infections with hookworms (two studies), Toxocara or Toxascaris ascarids (one study each) or Trichuris whipworms (two studies). In each study, dogs were assigned to blocks of two animals each, based on decreasing pre-treatment body weight and were randomly allocated to one of two groups consisting of eight, nine or 10 dogs: untreated (control) or treated with the combination chewable tablet formulation. Chewable tablets were combined to provide doses of actives as close as possible to the minimum effective dose of afoxolaner and milbemycin oxime, i.e., 2.5 mg/kg body weight and 0.5 mg/kg body weight, respectively, once on Day 0. For parasite recovery and count, dogs were euthanized humanely and necropsied seven or eight days after treatment. A single treatment with afoxolaner plus milbemycin oxime chewable tablets provided 94.8% and 90.9% efficacy against adult Ancylostoma braziliense and A. caninum, respectively, 97.8% and 99.4% efficacy against adult Toxocara canis and Toxascaris leonina, respectively, and ≥98.3% efficacy against adult Trichuris vulpis. Compared to untreated controls, nematode counts of the treated dogs were significantly reduced (F-test; p<0.002). In addition, analysis of the pooled data across studies revealed that treatment with afoxolaner plus milbemycin oxime chewable tablets reduced adult Uncinaria stenocephala burdens by 74.9% (p=0.002). All dogs tolerated the treatment well based on clinical observations post-treatment and daily clinical observations. No adverse experiences or other clinical problems related to the treatment were observed throughout the studies. The results of this series of controlled studies demonstrated high efficacy and excellent acceptability and safety of the afoxolaner plus milbemycin oxime chewable tablets when administered for treatment of a broad range of canine intestinal nematode infections., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Five controlled, blinded and randomized studies were conducted to examine the efficacy of a single topical application of a combination of fipronil, (S)-methoprene, eprinomectin, and praziquantel (BROADLINE(®), Merial) against induced infestations with Ixodes ticks on cats. Three studies investigated the efficacy against Ixodes ricinus and two against Ixodes scapularis. In each study, purpose-bred cats were assigned at random to an untreated group or to a treated group. For the studies using I. ricinus, cats were infested with 50 female ticks and a similar number of males 2 days before treatment application, and weekly afterwards on between four and six occasions. For the studies using I. scapularis, cats were infested with a total of 50 ticks (approximately 25 females and 25 males) according to the same schedule as for I. ricinus. Tick counts for the evaluation of efficacy were performed 48 h after treatment and 48 h after the subsequent weekly infestations. Weekly attachment rates to untreated cats of at least 29% for I. ricinus and at least 30% for I. scapularis demonstrated consistently that the ticks were vigorous and that the attachment rates were adequate for efficacy evaluation. In the I. ricinus studies, an efficacy of at least 93% was demonstrated for up to 37 days after the treatment. In the I. scapularis studies, the efficacy level was at least 95% 30 days after the treatment. The product was well tolerated and caused no adverse reaction., (Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.)

A novel topical combination product (BROADLINE(®), Merial) composed of fipronil, (S)-methoprene, eprinomectin and praziquantel was evaluated for safety and efficacy against nematode and cestode infections in domestic cats. The study comprised a multi-centre, positive control, blinded, field study, using a randomized block design based on order of presentation for allocation. In total 196 client-owned cats, confirmed as positive for naturally acquired infections of nematodes and/or cestodes by pre-treatment faecal examination, were studied in seven countries in Europe. Pre-treatment faecal examination revealed the presence of Toxocara, hookworm, Capillaria and/or spirurid nematode infections in 129, 73, 33 or 1 cat(s), respectively; infections with taeniid and Dipylidium cestodes were demonstrated in 39 and 17 cats, respectively. Cats were allocated randomly to one of two treatments in a ratio of 2, topical fipronil (8.3%, w/v), (S)-methoprene (10%, w/v), eprinomectin (0.4%, w/v) and praziquantel (8.3%, w/v) (BROADLINE(®), Merial; 130 cats); and 1, topical PROFENDER(®) Spot-On (Bayer; 66 cats) and treated once on Day 0. For evaluation of efficacy, two faecal samples were collected, one prior to treatment (Day -4 ± 4 days) and one at the end of the study (Day 14 ± 5 days). These were examined for fecal forms of nematode and cestode parasites. For evaluation of safety, cats were examined by a veterinarian before treatment and at the end of the study, and cat owners recorded the health status of their cats daily until the end of the study. For cats treated with Broadline(®), the efficacy was >99.9%, 100%, and 99.6% for Toxocara, hookworms, and Capillaria, respectively; and the efficacy was >99.9%, >99.9%, and 98.5%, respectively, for the cats treated with Profender(®) (p<0.001 for all nematodes and both treatments). Efficacy was 100% for both cestodes for both treatments (p<0.001). No treatment related adverse experiences were observed throughout the study. For both treatments, every cat that completed the study was given a safety score of 'excellent' for both local and systemic evaluations. The topical combination product of fipronil, (S)-methoprene, eprinomectin and praziquantel was shown to have an excellent safety profile and demonstrated high levels of efficacy when administered once as topical solution to cats infected with nematodes and cestodes under field conditions., (Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.)

Four studies were conducted to examine the efficacy of a novel topical combination of fipronil, (S)-methoprene, eprinomectin, and praziquantel (BROADLINE(®), Merial) against Ancylostoma tubaeforme and Ancylostoma braziliense hookworms of cats. In each study, purpose-bred cats were randomly assigned to treatment groups of 10 or 12 cats per group. In three studies the cats were inoculated with A. tubaeforme and in one study with A. braziliense. The inoculations were undertaken on a schedule which resulted in the hookworms reaching the fourth larval stage in two of the studies, or the adult stage in four of the studies, by the day of treatment. In each study there was also an untreated control and 1 or 2 groups treated with the novel combination. In the two studies where efficacy against the fourth larval stage of A. tubaeforme was tested, the efficacy recorded was 100%. In the three studies where efficacy against the adult stage of A. tubaeforme was tested, efficacy of 100% was also confirmed. In the study where efficacy against the adult stage of A. braziliense was tested efficacy was 99.5%., (Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.)

The efficacy of a novel topical combination formulation of fipronil, (S)-methoprene, eprinomectin and praziquantel against naturally acquired intestinal nematode and cestode infections in cats was evaluated in seven negative control, blinded studies. Cats were selected based on a pre-treatment faecal examination indicating a patent infection with at least hookworms (two studies), Toxocara ascarids (one study), taeniid cestodes (two studies) or Dipylidium cestodes (two studies). In each study, cats were assigned randomly to blocks of two animals each, based on decreasing pre-treatment body weight and were randomly allocated to one of two groups of six to 12 cats: untreated (control) or treated with topical fipronil (8.3%, w/v), (S)-methoprene (10%, w/v), eprinomectin (0.4%, w/v) and praziquantel (8.3%, w/v) (BROADLINE(®), Merial) at 0.12 mL/kg body weight (providing a minimum of 10mg fipronil+12 mg S-methoprene+0.5mg eprinomectin+10mg praziquantel per kg body weight). The topical treatment was administered directly on the skin in the midline of the neck in a single spot once on Day 0. For parasite recovery and count, cats were euthanized humanely and necropsied seven or ten days after treatment. A single treatment with the novel topical combination product provided 91% efficacy against Ancylostoma braziliense, ≥ 99% efficacy against Ancylostoma tubaeforme, and >97% efficacy against Toxocara cati. Similarly, excellent efficacy was established against Taenia taeniaeformis, Dipylidium caninum and Diplopylidium spp. as demonstrated by >97% and up to 100% reductions of cestode counts in the treated cats when compared to the untreated controls (P<0.01). All cats accepted the treatment well based on health observations post-treatment and daily health observations. No adverse experiences or other health problems were observed throughout the studies. The results of this series of controlled studies demonstrated high efficacy and excellent acceptability of the novel topical combination formulation of fipronil, (S)-methoprene, eprinomectin and praziquantel against a broad range of feline intestinal nematode and cestode infections., (Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.)

Although foxes are the main reservoir of Echinococcus multilocularis, it is recognized that dogs and cats also may become infected. In cats the infection and egg production rates are usually low. Nevertheless, cats are a potential source of transmission of E. multilocularis. Due to the high human medical significance of E. multilocularis infection, it is important in endemic areas that owned cats are dewormed regularly. This paper presents the efficacy results of a new topical formulation, Broadline(®) (Merial) tested against E. multilocularis infection in cats. Two blinded laboratory studies were conducted to evaluate this novel topical combination of fipronil, (S)-methoprene, eprinomectin, and praziquantel against E. multilocularis. In each study, purpose-bred cats were assigned randomly to two treatment groups of 10 cats each: one untreated control group and one group treated at the minimum therapeutic dose of 0.12 mL/kg bodyweight to deliver 10mg fipronil, 12 mg (S)-methoprene, 0.5mg eprinomectin and 10mg praziquantel/kg bodyweight. The cats were inoculated orally with E. multilocularis protoscolices, 22 or 23 days before treatment. Based on necropsy and intestinal worm count, 8 or 11 days after treatment, the two studies confirmed 100% efficacy of Broadline(®) against adult E. multilocularis., (Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.)

The efficacy of a novel topical fipronil, (S)-methoprene, eprinomectin and praziquantel combination product (BROADLINE(®), Merial) was evaluated against adult Toxascaris leonina ascarids in experimentally infected cats in two controlled studies under an identical protocol. For each study, 30 nematode-naive, purpose-bred European Short Hair cats were inoculated orally with approximately 300 larvated T. leonina eggs. Twenty-two and 24 cats, respectively, that were shown to be positive for Toxascaris eggs by pre-treatment faecal examination were subsequently included in the two studies. In each study, the animals were allocated randomly to an untreated (control) group or to a treatment group. The treatment was a novel topical combination: fipronil (8.3%, w/v), (S)-methoprene (10%, w/v), eprinomectin (0.4% w/v) and praziquantel (8.3% w/v). Treatment was applied on Day 0 at 0.12 mL/kg bodyweight. For parasite recovery and count, cats were euthanized humanely seven days after treatment and necropsied. All untreated cats harboured adult T. leonina (range, 1-31 nematodes). The treatment provided a high level of efficacy against adult T. leonina in both studies (95.8% and 98.1%, respectively p<0.001). All cats accepted the treatment well based on hourly post-treatment observations for 4h and daily observations thereafter. No adverse experiences or other health problems were observed throughout the studies. Thus the data indicate that this novel combination product will provide a safe and effective treatment against T. leonina in cats., (Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.)

The efficacy of eprinomectin in an extended-release injection (ERI) formulation was evaluated in cattle harbouring induced infestations of Sarcoptes scabiei var. bovis (sarcoptic mange) in three studies conducted in Germany (two studies) and Austria (one study). A total of 44 cattle were included in the studies, 12 in one study and 16 in each of the other two studies. Approximately eight weeks following initial induced infestation, cattle in each study were formed into replicates of two animals each on the basis of pre-treatment bodyweights. Within replicates the animals were randomly allocated to one of two treatments: ERI vehicle (control) or Eprinomectin 5% (w/v) ERI (1.0 mg eprinomectin/kg). Treatments were administered at 1 mL/50 kg bodyweight by subcutaneous injection in front of the shoulder once on day 0. The number of live mites in skin scrapings was determined prior to treatment and at weekly intervals for eight weeks after treatment. Severity of skin lesions was evaluated and scored when skin scrapings were taken. In all studies, animals were weighed before infestation and again prior to and at 56 days after treatment. Mite counts for treated cattle were significantly (p<0.05) lower than counts for controls from Day 7 onwards. Cattle treated with Eprinomectin ERI were Sarcoptes mite-free from seven, 21 or 28 days post-treatment to the end of the study in the three studies, and lesions regressed accordingly. Mean weight gain over the post-treatment period was significantly higher for treated cattle than for controls in two studies. All animals accepted the treatment well., (Copyright © 2012 Elsevier B.V. All rights reserved.)

During 2011, faeces from 235 owned domestic cats from a rural area in western Hungary were examined using standard coproscopical techniques. The overall prevalence of cats with endoparasites was 39.6% (95% CI 33.3-46.1). The most frequently identified faecal forms were those of ascarids (Toxocara, 17.4%; Toxascaris 7.2%), followed by those of Aelurostrongylus lungworms (14.5%), hookworms (11.1%), taeniid cestodes (4.7%), Cystoisospora coccidians (4.3%), and capillarids (3.8%). Single and multiple infections with up to five parasites concurrently were founded in 24.7% and 14.9% of the cats, respectively. Mixed endoparasite infections were recorded more frequently (p=0.0245) in cats greater than one year old compared to younger cats. Young cats (≤ 1 year) were parasitized more frequently (p<0.05) with ascarids and Cystoisospora spp. but demonstrated infections of hookworms, lungworms and taeniid cestodes less often than the older cats. Cats with taeniid infection were more likely (p<0.05) to harbour Toxocara, hookworm, Aelurostrongylus, and capillarid infections than cats without taeniid cestodes. Cats of owners who claimed the use of wormers were less frequently helminth-positive compared to cats whose owners did not use anthelmintics (21.2% vs. 44.4%; p=0.001). A subset of 115 faecal samples screened by a coproantigen ELISA revealed Giardia-specific antigen in 37.4% samples. Giardia cysts were found by immunofluorescent staining in 30 of the 43 samples tested positive for Giardia by ELISA. In addition, ectoparasites collected from 82 cats by body search and combing were identified. Fleas (1-30 per cat), biting lice (Felicola subrostratus), and ticks (1-5 per cat) were isolated from 58, 1 and 43 cats, respectively. Ctenocephalides felis was identified on all flea infested cats while single specimens of C. canis and Pulex irritans were recovered from three and two cats, respectively. All but one tick collected were adult Ixodes ricinus; the single other tick was a nymph of I. canisuga. By providing basic data on the epidemiology of parasitic infections, the results of this survey should emphasize the need of attending to parasites of cats from the veterinary point of view with respect to both appropriate diagnostics and control., (Copyright © 2012 Elsevier B.V. All rights reserved.)

The purpose of the present study was to confirm the efficacy of 10% (w/v) fipronil spot-on (Frontline spot-on for cats) in the treatment of feline cheyletiellosis under field conditions. A total of 16 cats of different breeds, sexes, 4 months to 14 years of age and weighing 0.5-6 kg were treated with a single topical application of 10% (w/v) fipronil spot-on according to label directions. The animals were naturally infested with Cheyletiella mites and housed in their normal environment throughout the study. Animals were selected based on clinical signs and infestation was confirmed by demonstration of mites. Mite counts and a clinical assessment of mite infestations (i.e. skin lesions and/or scales) were performed on days 0 and approximately days 14 and 28. Individual counts on day 0 ranged from 1 to 40 mites on individual animals. No mites were detected on cats treated with 10% (w/v) fipronil spot-on (Frontline spot-on for cats) at both post-treatment evaluations. Typical skin lesions and/or scales were present in all animals pre-treatment. In 56% of the cats, the lesions resolved within 14 days after treatment. At the final assessment, 75% cats were free of lesions. Two cats that still had clinical signs on day 28 were suspected of having allergic reactions to food or environmental allergens. The lesions on the remaining two cats could not be related to a specific cause. The efficacy of fipronil in elimination of mites was 100% on each occasion when compared to the pre-treatment count. The results of this study demonstrated that fipronil in a topical formulation is highly effective (100%) for the elimination of an existing Cheyletiella mite infestation under field conditions following a single topical application in cats.

A randomised block design study was conducted to evaluate the effects of mange on cattle. Twenty-four Simmentaler Fleckvieh bulls were formed into eight replicates of three bulls based on Day -56 body weight (288-414 kg). Within replicates bulls were randomly allocated to groups G1: uninfested control, G2: infested control or G3: infested, treated with 0.2mg ivermectin/kg (1% ivermectin injection; IVOMEC, Merial) on Day 0. The G2 and G3 bulls were infested with Sarcoptes/Chorioptes mites on Days -56 and -49. Feed consumption was recorded daily throughout the study (Days -56 to 56). Body weights were measured and serum samples collected. Mites were counted at bi-weekly intervals from Day -14 on. The carcasses of the bulls and the leather produced from their hides were evaluated. Differences between variables were declared significant if P

Two trials were conducted to confirm the efficacy of ivermectin paste against endoparasites of horses. In these trials, 20 ponies were treated with ivermectin oral paste at 200 mcg x kg body weight once on Day 0, and 20 ponies served as unmedicated controls. The animals carried naturally acquired parasite infections as confirmed by pretrial fecal examination. The animals were necropsied for worm recovery on Days 14, 15 or 16. Parasites recovered were identified to species. Horses treated with ivermectin had significantly (P<0.05) fewer (>99.0% reduction) adult small strongyles (Coronocyclus spp including C. coronatus, C. labiatus, C. labratus; Cyathostomum spp including C. catinatum, C. pateratum; Cylicocyclus spp including C. ashworthi, C. elongatus, C. insigne, C. leptostomum, C. nassatus, C. radiatus; Cylicodontophorus bicoronatus; Cylicostephanus spp including C. asymetricus, C. bidentatus, C. calicatus, C. goldi, C. longibursatus, C. minutus; Gyalocephalus capitatus; Parapoteriostomum spp including P. euproctus, P. mettami; Petrovinema poculatum; Poteriostomum spp including P. imparidentatum, P. ratzii) and adult large strongyles (Strongylus edentatus, S. vulgaris; Triodontophorus spp including T. brevicauda, T. serratus; Craterostomum acuticaudatum) than the controls. Ivermectin was also highly effective (94% to >99%, P<0.05-0.01) against Gasterophilus intestinalis larvae, Habronema spp., Oxyuris equi, Parascaris equorum. The data from these two trials confirm that ivermectin paste administered to horses orally at 200mcg x kg(-1) continues to be highly effective for treatment and control of a broad range of small and large strongyle species as well as other species of gastrointestinal parasites.

To evaluate the prophylactic and therapeutic effects of an ivermectin controlled-release capsule (IVM-CRC) on the productivity of growing sheep infested with Psoroptes ovis 24 male and 24 female Merino landrace lambs, 5-6 months old and weighing 21.2-35.0 kg, were used. Sixteen replicates of three animals were formed based on sex and Day 0 body weight. Within each replicate animals were randomly allocated to one of three groups: untreated control; IVM-CRC on Day 0; IVM-CRC on Day 84. For treatment an IVM-CRC for sheep weighing 20-45 kg was used which is designed to deliver ivermectin at a minimum dose of 20 microg/kg/day for 100 days. The lambs were infested with 50-60 P. ovis mites each on days 14 and 21. The animals were shorn on Day 126. After slaughter on Day 127 the quality of the leather produced from their skins was evaluated. The IVM-CRC treatment on Day 0 prevented the establishment of P. ovis. All untreated lambs became infested. The lambs treated with an IVM-CRC on Day 84 became mite-free from Day 112 onwards. The lambs which were treated on Day 0 had significantly (p<0.05) greater clean fleece weight (1.5 kg) and fleece yield (52.1%) than the untreated controls (0.9 kg and 34.1%, respectively) or than lambs treated on Day 84 (1.0 kg and 47.8%, respectively). Clean fleece weight and fleece yield were in the tendency (p=0.055) or significantly (p<0. 001) greater, respectively, for lambs treated on Day 84 than for the untreated controls. The chrome tanned dried crust leather of all untreated controls and six of the 16 lambs treated on Day 84 showed grain surface defects such as discolourations, indurations and coarse, pitted grain. The useful (defect-free) leather size was significantly (p<0.01) higher for the lambs treated on Day 0 (100%) than for the lambs treated on Day 84 (82.7%) and the untreated controls (7.8%). The physical testing revealed that the leather of sheep treated on Day 0 had significantly (p<0.05) higher thickness, elongation break and tear resistance than the leather of both untreated controls and sheep treated on Day 84. There were no significant differences in the physical characteristics of the leather of the untreated controls and the sheep treated on Day 84.

To evaluate the prophylactic and therapeutic effects of an ivermectin controlled-release capsule (IVM-CRC) on the productivity of growing sheep infested with Psoroptes ovis 24 male and 24 female Merino landrace lambs, 5-6 months old and weighing 21.2-35.0 kg, were used. Sixteen replicates of three animals were formed based on sex and Day 0 body weight. Within each replicate animals were randomly allocated to one of three groups: untreated control; IVM-CRC on Day 0; IVM-CRC on Day 84. For treatment an IVM-CRC for sheep weighing 20-45 kg was used which is designed to deliver ivermectin at a minimum dose of 20 microg/kg per day for 100 days. The lambs were infested with 50-60 P. ovis mites each on Days 14 and 21. Mites in skin scrapings were counted on Days 70, 84, 98, 112 and 126. Body weight and feed consumption were measured every 2 weeks from Day 0 to 126. The animals were slaughtered on Day 127 and their carcasses evaluated. The IVM-CRC treatment on Day 0 prevented the establishment of P. ovis. All untreated lambs became infested. The lambs treated with an IVM-CRC on Day 84 became mite-free from Day 112 onwards. The lambs treated on Day 0 had significantly (p<0.05) greater body weight gain from Day 0 to 84 (13.9 kg) and Day 0 to 126 (20.9 kg) than the untreated controls (9.6 and 12.8 kg, respectively) and the sheep treated on Day 84 (8.4 and 14.9 kg, respectively). Feed consumption (Days 0-126) for sheep treated with the IVM-CRC on Day 0 was higher than for sheep treated on Day 84 (p<0.05) and for the untreated controls (p<0.1). The carcasses of sheep treated with the IVM-CRC on Day 0 had significantly (p<0.05) higher warm and cold weights, carcass yield, rib eye area and back fat thickness than the untreated control group and the sheep treated with the IVM-CRC on Day 84. The sheep treated with the ivermectin CRC on either Day 0 or 84 had significantly (p<0.05) better muscle scores and lower muscle pH 1h post-slaughter than the untreated controls. There was no significant (p>0.1) difference between warm and cold carcass weights, carcass yield and rib eye area between sheep treated on Day 84 and untreated controls.

A controlled trial was conducted to evaluate the efficacy of the intraruminal ivermectin controlled-release capsule (CRC) (IVOMEC Maximizer CR Capsule for Sheep, Merial Ltd.) against induced incoming third-stage larvae and established adult infections with some rarer gastrointestinal nematode parasites of sheep. Twenty-one worm-free lambs were allocated by restricted randomisation based on body weight within sex to one of the following treatments: unmedicated control, ivermectin CRC given on Day 0 prior to induced infection, and ivermectin CRC given on Day 70 after establishment of induced infection. The ivermectin CRC delivers ivermectin at a minimum dose rate of 20 microg/kg/day for 100 days. Infections were induced by daily administration of third-stage larvae for five consecutive days. Nematodes were counted on Day 84, 14 days after treatment of established infection. The treatment with the ivermectin CRC prevented the establishment of Ostertagia leptospicularis, O. ostertagi, Bunostomum trigonocephalum, Cooperia oncophora, C. punctata, C. surnabada, Nematodirus helvetianus, N. roscidus and Strongyloides papillosus by >99% as compared with the untreated controls (p < 0.01). The administration of the ivermectin CRC reduced established adult infections of O. ostertagi, B. trigonocephalum, C. oncophora, C. punctata, C. surnabada, N. roscidus and S. papillosus by >99% (p < 0.01), and reduced established adult infections of O. leptospicularis and N. helvetianus by 96.5 and 98.4% (p < 0.01), respectively.