Search

Background: Five studies were conducted to evaluate the effect of a new combination of fipronil and permethrin on cat fleas, Ctenocephalides felis, when applied to dogs, including dogs that underwent water exposure or shampooing. Methods: In each study, 16 dogs were allocated to two groups. Each dog was infested with 100 unfed adult fleas on Days -1, 7, 14, 21 and 28. Eight dogs were treated with a new topical spot-on formulation containing 6.76% w/v fipronil + 50.48% w/v permethrinon Day 0; and eight dogs served as untreated controls. Twenty-four or 48 h after treatment or subsequent infestation, each dog was combed to remove and count live fleas. In addition, the dogs were subjected to different levels of water or shampoo exposure. In study 1, dogs were not subjected to any water exposure or shampooing; in study 2, dogs were water immersed twice during the month on Days 10 and 24; in study 3, dogs were water immersed three times on Days 10, 17 and 24; and in studies 4 and 5, dogs were shampooed once on Day 17. Results: All groups of dogs administered a single topical treatment with a combination of fipronil and permethrin had significantly (p < 0.005) lower flea counts than untreated controls 24 h and 48 h post-treatment or post-infestation, regardless of whether they underwent water exposure/shampooing or not. The reductions in C. felis counts were between 98.4% and 100% at all time points in all studies. Conclusions: The new topical spot-on formulation of fipronil and permethrin maintains a high level of protection of dogs against C. felis flea infestations even when the dogs are exposed to environmental factors that are believed to adversely affect efficacy, such as water exposure or shampooing. [ABSTRACT FROM AUTHOR]

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 48h after treatment and 48h 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. [ABSTRACT FROM AUTHOR]

The efficacy of a novel topical combination of fipronil 8.3% (w/v), (S)-methoprene 10% (w/v), eprinomectin 0.4% (w/v) and praziquantel 8.3% (w/v) (BROADLINE�®) was tested against adult and immature stages of Ctenocephalides felis fleas in six studies. For that purpose, fleas from different colonies from North America, Germany and South Africa were used to induce infestations in cats under laboratory conditions. In each study, between 12 and 16 cats were allocated randomly to 2 groups. Cats in Group 1 were not treated and served as controls. Cats in Group 2 were treated once on Day 0 with BROADLINE�® at the minimum recommended dosage of 0.12mg/kg body weight. In 4 studies, all animals were infested experimentally with unfed C. felis (100�±5) on Days 2 (or 1), 7, 14, 21, 28 and 35. Live fleas were counted 24h post-treatment or infestation. In 2 additional studies, animals were infested at the same frequency with gravid C. felis fleas (100�±5) that were fed previously on an untreated host. Forty-eight hours post-infestation, flea eggs were collected, counted and incubated for the evaluation of the reduction of emergence of adults. The combined curative efficacy against adult fleas at 24h after treatment was 94.3% and the combined preventive efficacy values remained greater than 95.9% at 24h after 5 subsequent weekly infestations. In addition, the product reduced dramatically the emergence of new adult fleas for at least 5 weeks (>98.1% for one month and 93.2% at 5 weeks after infestation), demonstrating its efficiency in preventing environmental contamination by immature stages. [ABSTRACT FROM AUTHOR]

Abstract: Five laboratory studies were conducted to confirm that a single topical dose of the novel combination of fipronil, amitraz and (S)-methoprene, CERTIFECT™ (Merial Limited, GA, USA), is efficacious for the rapid control of pre-existing infestations and the prevention of new infestations with Ixodes scapularis, Dermacentor variabilis, Amblyomma americanum and Amblyomma maculatum for at least 28 days on dogs. In each study, 8 male and 8 female purpose-bred, laboratory beagles were randomly assigned to one of two study groups (treated and untreated). Starting on the day before treatment, each dog was infested weekly with about 30 or 50 ticks, depending on the study. Treatment with the novel combination rapidly eliminated pre-existing infestations and controlled weekly re-infestations for at least 28 days. Pre-existing infestations with all four tick species were rapidly and effectively reduced, with post-treatment therapeutic efficacies ranging from 91.7 to 99.5% within 18–48h post treatment. Amblyomma maculatum numbers were significantly (p <0.05) reduced on treated dogs from the first tick counts as early as 6h post-treatment. All subsequent infestations with each of the 4 tick species were quickly disrupted, with prophylactic efficacies greater than 90% within 18–48h post-infestation for at least a full month. Because the combination of fipronil, amitraz and (S)-methoprene quickly starts disrupting and killing ixodid ticks within hours of treatment, with similar high levels of efficacy maintained for at least 28 days in these and other studies, the authors conclude that a single topical treatment with CERTIFECT may prevent the transmission of most infectious agents carried by ixodid ticks for at least one month. [Copyright &y& Elsevier]

Discusses software reliability measurements. Use of reliability methods at Motorola Corporation's World Wide Systems Group; Gap between reliability measurement theory and practice; Factors that influence the target system's reliability.