A randomized, controlled, single-blinded, multicenter evaluation of the efficacy and safety of a once weekly two dose otic gel containing florfenicol, terbinafine and betamethasone administered for the treatment of canine otitis externa.

BACKGROUND: Otitis externa is a common problem in small animal practice. Compliance with daily treatment is a major cause of treatment failure. The hypothesis tested is that a novel otic gel applied to the ear canal twice with a one-week interval is as efficacious as a daily otic suspension in the treatment of canine otitis externa. The study included 286 privately owned dogs with otitis externa. In this single blinded randomized study, enrolled dogs received either an otic gel containing 1% florfenicol, 1% terbinafine and 0.1% betamethasone acetate twice with a one-week interval or a suspension containing hydrocortisone aceponate, miconazole and gentamicin daily for 5 days. Ears were cleaned with saline prior to administration of the first dose of medication. Dogs were evaluated at day (D) 0, 7, 28 and 56 with an otitis index score (OTIS-3), otic culture and cytology, pain and pruritus, and overall response to treatment (owner and investigator evaluation). Outcome measures were improvement of the OTIS-3 and number of dogs in clinical remission at each time point. RESULTS: OTIS-3 decreased significantly (p < 0.0001) by 63 and 64% for the otic gel and by 63 and 61% for the suspension on D28 and D56 respectively. There was no significant difference between groups at any time point with regard to clinical success, pain, pruritus, overall assessments or otic cytology and culture. The treatment response was considered excellent or good by approximately three quarters of both the clinicians and Owners. Otitis recurrence at D56 was seen in 11% of both groups. Adverse events attributable to the ear medications were not noted. CONCLUSIONS: Administering an otic gel twice at a one-week interval is an effective, safe and convenient way to treat canine otitis externa.

Effect of benazepril and robenacoxib and their combination on glomerular filtration rate in dogs.

Combined use of angiotensin-converting enzyme inhibitors and nonsteroidal anti-inflammatory drugs may induce acute kidney injury, especially when combined with diuretics. The objective of this investigation was to evaluate the effect of benazepril, robenacoxib and their combination in healthy dogs. In each of two studies (studies 1 and 2), 32 beagle dogs were randomized into one of four groups in a parallel-group design. Groups received once-daily oral treatment for 7 days with placebo, benazepril, robenacoxib or benazepril plus robenacoxib. In study 2, all dogs received additionally 2 mg/kg furosemide orally twice daily. The primary endpoint was the glomerular filtration rate (GFR) estimated from the plasma clearance of iohexol. Secondary endpoints included standard clinical monitoring and, in study 2, plasma renin activity, urine volume, specific gravity and aldosterone concentration and water intake. Administration of furosemide induced diuresis, reduced GFR and activated the renin-aldosterone-angiotensin system. Benazepril and robenacoxib, administered alone or in combination, were tolerated well, did not decrease GFR with or without co-administration of furosemide and significantly reduced urinary aldosterone concentrations. No increased risk of acute kidney injury was identified with the combination of benazepril and robenacoxib in healthy dogs. Different effects might occur in dogs with heart or renal disease.

Evaluation of the dose-response relationship of oral robenacoxib in urate crystal-induced acute stifle synovitis in dogs.

The objective of the study was to establish the dose-response relationship for robenacoxib, a selective cyclooxygenase (COX)-2 inhibitor, in a urate crystal model of acute synovitis. In a randomized partial Latin square design trial, 12 beagle dogs were administered orally single doses of robenacoxib (0.5, 1, 2, 4 and 8 mg/kg), placebo and the positive control meloxicam (0.1 mg/kg), 3 h after injection of sodium urate crystals into a stifle joint. Dogs were assessed for weight bearing on a force plate and by subjective clinical orthopaedic observations. Robenacoxib produced dose-dependent improvement in weight bearing, and decreased pain on palpation and joint swelling, over the dose range 0.5-2 mg/kg with no further increase in effect over the range 2-8 mg/kg. For weight bearing on the force plate, the ED50 of robenacoxib was 0.6-0.8 mg/kg. The onset of action and time to peak effect of robenacoxib were faster (respectively, 2-2.5 h and 3-5 h) than for meloxicam (respectively, 3 h and 6 h). Robenacoxib significantly inhibited COX-2 at all doses, with dose-related activity. Robenacoxib did not inhibit COX-1 over the dose range 0.5-4 mg/kg, but produced transient inhibition at 8 mg/kg. In conclusion, oral administration of robenacoxib over the dose range 0.5-8 mg/kg demonstrated significant analgesic and anti-inflammatory efficacy in dogs.

Effect of Cyclooxygenase(COX)-1 and COX-2 inhibition on furosemide-induced renal responses and isoform immunolocalization in the healthy cat kidney.

BACKGROUND: The role of cyclooxygenase(COX)-1 and COX-2 in the saluretic and renin-angiotensin responses to loop diuretics in the cat is unknown. We propose in vivo characterisation of isoform roles in a furosemide model by administering non-steroidal anti-inflammatory drugs (NSAIDs) with differing selectivity profiles: robenacoxib (COX-2 selective) and ketoprofen (COX-1 selective). RESULTS: In this four period crossover study, we compared the effect of four treatments: placebo, robenacoxib once or twice daily and ketoprofen once daily concomitantly with furosemide in seven healthy cats. For each period, urine and blood samples were collected at baseline and within 48 h of treatment starting. Plasma renin activity (PRA), plasma and urinary aldosterone concentrations, glomerular filtration rate (GFR) and 24 h urinary volumes, electrolytes and eicosanoids (PGE2, 6-keto-PGF1α, TxB2), renal injury biomarker excretions [N-acetyl-beta-D-glucosaminidase (NAG) and Gamma-Glutamyltransferase] were measured. Urine volume (24 h) and urinary sodium, chloride and calcium excretions increased from baseline with all treatments. Plasma creatinine increased with all treatments except placebo, whereas GFR was significantly decreased from baseline only with ketoprofen. PRA increased significantly with placebo and once daily robenacoxib and the increase was significantly higher with placebo compared to ketoprofen (10.5 ± 4.4 vs 4.9 ± 5.0 ng ml(-1) h(-1)). Urinary aldosterone excretion increased with all treatments but this increase was inhibited by 75 % with ketoprofen and 65 % with once daily robenacoxib compared to placebo. Urinary PGE2 excretion decreased with all treatments and excretion was significantly lower with ketoprofen compared to placebo. Urinary TxB2 excretion was significantly increased from baseline only with placebo. NAG increased from baseline with all treatments. Immunohistochemistry on post-mortem renal specimens, obtained from a different group of cats that died naturally of non-renal causes, suggested constitutive COX-1 and COX-2 co-localization in many renal structures including the macula densa (MD). CONCLUSIONS: These data suggest that both COX-1 and COX-2 could generate the signal from the MD to the renin secreting cells in cats exposed to furosemide. Co-localization of COX isoenzymes in MD cells supports the functional data reported here.

Robenacoxib vs. carprofen for the treatment of canine osteoarthritis; a randomized, noninferiority clinical trial.

Robenacoxib is a member of the coxib class of nonsteroidal anti-inflammatory drugs (NSAID), with high selectivity for the cyclooxygenase (COX)-2 isoform of COX. In this study, the efficacy and tolerability of robenacoxib were compared with those of carprofen in canine osteoarthritis in a multi-centre, prospective, randomized, blinded, positive-controlled noninferiority clinical trial. Both drugs were administered orally once daily at recommended dosages: robenacoxib at 1-2 mg/kg (n = 125 dogs) and racemic carprofen at 2-4 mg/kg (n = 63 dogs) for a total of 12 weeks. The efficacy of the test compounds was assessed by veterinary investigators and owners using numerical rating scales at baseline and days 7, 14, 28, 56 and 84. In both groups, all scores were significantly (P < 0.0001) improved compared with baseline at all time points (days 7-84). Robenacoxib had noninferior efficacy to carprofen for the primary endpoint, the global functional disability, both for all dogs and for the subgroup of dogs in which robenacoxib was not administered during meals. Noninferiority was also demonstrated for three of six veterinary investigator secondary endpoints and four of six owner efficacy endpoints. For haematology and clinical chemistry variables, there were some significant differences from baseline levels but no differences between groups. There were no differences between groups in the frequencies of adverse events, which were reported in 46% dogs with robenacoxib and 52% with carprofen (P = 0.44), which were most frequently mild events affecting the gastrointestinal tract. In conclusion, noninferior efficacy and tolerability of robenacoxib compared with carprofen was demonstrated in dogs with osteoarthritis.

Safety of oral robenacoxib in the cat.

The safety of robenacoxib, a nonsteroidal anti-inflammatory drug with high selectivity for inhibition of the cyclooxygenase (COX)-2 isoform of COX, was investigated in the cat in two randomized, blinded, placebo-controlled, parallel-group studies. Robenacoxib was administered orally to healthy young domestic short-hair cats at dosages of 0 (placebo), 5 and 10 mg/kg once daily for 28 days (study 1) and at 0 (placebo), 2, 6 and 10 mg/kg twice daily for 42 days (study 2). The recommended minimum dosage for robenacoxib tablets in cats is 1 mg/kg once daily (range 1-2.4 mg/kg). Relative to placebo treatment, no toxicologically significant effects of robenacoxib were recorded in either study, based on general observations of health, haematological and clinical chemistry variables and urinalyses in life, and by post mortem organ weight, gross pathology and histopathology assessments. Pharmacokinetic-pharmacodynamic simulations indicated that all dosages of robenacoxib were associated with marked inhibition of COX-2 at peak effect (median I(max) 97.8-99.4% inhibition) with lesser inhibition of COX-1 (median I(max) 26.8-58.3% inhibition). Inhibition of the COXs was short lasting, with >10% median inhibition persisting for 4.0 h for COX-2 and 1.5 h for COX-1. These levels of inhibition of COX-1 and COX-2 twice daily with robenacoxib were not associated with any detectable toxicity, suggesting that, as previously described in dogs, the high safety index of robenacoxib in cats may be related to a combination of its high COX-2 selectivity and short residence time in the central compartment.

Robenacoxib in the dog: target species safety in relation to extent and duration of inhibition of COX-1 and COX-2.

The safety of robenacoxib, a nonsteroidal anti-inflammatory drug with high selectivity for inhibition of the cyclooxygenase (COX)-2 isoform of COX, was investigated in the dog in two randomized, placebo-controlled, parallel group studies. Robenacoxib was administered orally once daily to healthy young beagle dogs at 0 (placebo), 10, 20 and 40 mg/kg for 1 month (Study 1) and at 0 (placebo), 2, 4, 6 and 10 mg/kg for 6 months (Study 2). Relative to placebo treatment, no significant adverse effects of robenacoxib were recorded in either study for clinical observations, haematological and clinical chemistry variables or macroscopic or microscopic lesions at necropsy. In Study 2, additional examinations identified no adverse effects of robenacoxib on buccal bleeding time, electrocardiographic and ophthalmoscopic examinations, urinalysis or stifle joint tissues. Pharmacokinetic-pharmacodynamic simulations indicated that all dosages of robenacoxib were associated with marked inhibition of COX-2 (median Emax 74-99% inhibition). For the highest dosage of robenacoxib (40 mg/kg in Study 1), the upper limit of the 90% tolerance interval was associated with 71% inhibition of COX-1 at Emax, but 50% inhibition persisted for only 3.5 h. This level of inhibition of COX-1 with robenacoxib was not associated with any detectable toxicity, suggesting that the high safety index of robenacoxib in dogs is a function of both its high COX-2 selectivity and short residence time in the central compartment.

In vitro and ex vivo inhibition of COX isoforms by robenacoxib in the cat: a comparative study.

Robenacoxib is a novel nonsteroidal anti-inflammatory drug (NSAID) developed for use in companion animals. Whole blood assays were used to characterize in the cat the pharmacodynamics of robenacoxib for inhibition of the cyclooxygenase (COX) isoforms, COX-1 and COX-2, in comparison with other NSAIDs. Based on in vitro IC(50) COX-1:IC(50) COX-2 ratios, robenacoxib was COX-2 selective (ratio = 32.2), diclofenac (ratio = 3.9) and meloxicam (ratio = 2.7) were only weakly COX-2 preferential, and ketoprofen (ratio = 0.049) was COX-1 selective. In an in vivo pharmacokinetic ex vivo pharmacodynamic study, after both p.o. (1-2 mg/kg) and subcutaneous (2 mg/kg) dosing, robenacoxib achieved peak blood concentrations rapidly (T(max) = 1 h for both administration routes) and was cleared from blood relatively rapidly (mean residence time was 1.70 h after p.o. and 1.79 h after subcutaneous dosing). In ex vivo COX isoform inhibition assays, orally (1-2 mg/kg) or subcutaneously (2 mg/kg) administered robenacoxib significantly inhibited COX-2, with a relatively short duration of action in the central compartment, and had no effect on COX-1. Therefore robenacoxib was COX-2 selective and spared COX-1 in vivo. In contrast, meloxicam (0.3 mg/kg via subcutaneous injection) inhibited both COX-1 and COX-2 isoforms significantly for at least 24 h, indicating nonselectivity in vivo.

Analgesic and anti-inflammatory actions of robenacoxib in acute joint inflammation in dog.

The objectives of this study were to establish dose-response and blood concentration-response relationships for robenacoxib, a novel nonsteroidal anti-inflammatory drug with selectivity for inhibition of the cyclooxygenase (COX)-2 isoenzyme, in a canine model of synovitis. Acute synovitis of the stifle joint was induced by intra-articular injection of sodium urate crystals. Robenacoxib (0.25, 0.5, 1.0, 2.0 and 4.0 mg/kg), placebo and meloxicam (0.2 mg/kg) were administered subcutaneously (s.c.) 3 h after the urate crystals. Pharmacodynamic endpoints included data from forceplate analyses, clinical orthopaedic examinations and time course of inhibition of COX-1 and COX-2 in ex vivo whole blood assays. Blood was collected for pharmacokinetics. Robenacoxib produced dose-related improvement in weight-bearing, pain and swelling as assessed objectively by forceplate analysis (estimated ED(50) was 1.23 mg/kg for z peak force) and subjectively by clinical orthopaedic assessments. The analgesic and anti-inflammatory effects of robenacoxib were significantly superior to placebo (0.25-4 mg/kg robenacoxib) and were non-inferior to meloxicam (0.5-4 mg/kg robenacoxib). All dosages of robenacoxib produced significant dose-related inhibition of COX-2 (estimated ED(50) was 0.52 mg/kg) but no inhibition of COX-1. At a dosage of 1-2 mg/kg administered s.c., robenacoxib should be at least as effective as 0.2 mg/kg of meloxicam in suppressing acute joint pain and inflammation in dogs.

Dose confirmation studies for monepantel, an amino-acetonitrile derivative, against fourth stage gastro-intestinal nematode larvae infecting sheep.

Monepantel is the first compound from the recently discovered amino-acetonitrile derivative (AAD) class of anthelmintics to be developed for use in sheep. Nine dose confirmation studies were conducted in Australia, New Zealand and Switzerland to confirm the minimum therapeutic oral dose of monepantel to control fourth stage (L4) gastro-intestinal nematode larvae in sheep (target species were Haemonchus contortus, Teladorsagia (Ostertagia) circumcincta, Teladorsagia trifurcata, Trichostrongylus axei, Trichostrongylus colubriformis, Trichostrongylus vitrinus, Cooperia curticei, Cooperia oncophora, Nematodirusbattus, Nematodirusfilicollis, Nematodirus spathiger, Chabertia ovina and Oesophagostomum venulosum). In each study, sheep infected with a defined selection of the target nematodes were treated with 2.5mg monepantel/kg liveweight. Following euthanasia and worm counting, efficacy was calculated against worm counts from untreated control groups. The results demonstrate high (95<100%) efficacy of monepantel when administered orally to sheep at 2.5mg/kg for most species tested. Efficacy levels against N. spathiger and O. venulosum were variable and failed to meet the required regulatory standard (> or =90%) in some studies. Efficacy was demonstrated against L4 stages of nematodes known to be resistant to either benzimidazole and/or levamisole anthelmintics (macrocyclic lactone resistant isolates were not available for testing). The broad-spectrum activity of monepantel against L4 larvae of common gastro-intestinal nematodes in sheep and its favorable safety profile represents a significant advance in the treatment of parasitic gastro-enteritis in this animal species. No adverse effects related to treatment with monepantel were observed.

Analytical determination and pharmacokinetics of robenacoxib in the dog.

An analytical method was developed and validated for the measurement of the novel analgesic and anti-inflammatory drug robenacoxib in blood and plasma of dogs and cats. To prevent nonreproducible carry-over effects, an initial solid phase extraction procedure was followed by high pressure liquid chromatography analysis for samples with concentrations in the range 500 to 20,000 ng/mL. To improve accuracy, samples of concentration 3 to 100 ng/mL were analyzed by liquid chromatography-mass spectrometry. Applying these methods, blood concentration-time profiles and pharmacokinetic variables of robenacoxib in dogs were determined in a four-phase cross-over study, which compared different routes of administration of the drug, including intravenous (i.v.) injection, oral application with and without feed, and subcutaneous (s.c.) application. After i.v. administration the mean clearance from blood was 0.81 L/kg/h, the volume of distribution was 0.77 L/kg for the elimination phase and 0.24 L/kg for steady-state, and the terminal half-life in blood was 0.63 h. Maximum blood concentrations were obtained in less than 1 h following oral or s.c. application. Absolute bioavailability was 88% after s.c. injection, 84% after oral administration to fasted dogs, but was reduced to 62% when applied orally to fed dogs. In canine and feline plasma the degree of binding of robenacoxib to plasma protein in vitro was greater than 98%. The blood:plasma concentration ratio was 0.44:1 in the dog and 0.65:1 in the cat. In conclusion analytical methods for the quantification of robenacoxib in blood and plasma in the dog and cat were developed and validated. In dogs, robenacoxib has good bioavailability after oral (84%) and subcutaneous (88%) administration.

Pharmacokinetics of monepantel and its sulfone metabolite, monepantel sulfone, after intravenous and oral administration in sheep.

The pharmacokinetic properties of the developmental Amino-Acetonitrile Derivative (AAD), monepantel and its sulfone metabolite, monepantel sulfone were investigated in sheep following intravenous (i.v.) and oral administrations. The sulfone metabolite was rapidly formed and predominated over monepantel 4 h after dosing, irrespective of the route of administration. The steady-state volume of distribution, total body clearance and mean residence time of monepantel were 7.4 L/kg, 1.49 L/(kg x h) and 4.9 h, respectively and 31.2 L/kg, 0.28 L/(kg x h) and 111 h, respectively for monepantel sulfone. The overall bioavailability of monepantel was 31%, but it was demonstrated that approximately the same amount of monepantel sulfone was produced whether monepantel was given intravenously or orally (AUC((0-infinity)) oral/AUC((0-infinity)) i.v. of 94% for monepantel sulfone), making oral administration a very efficient route of administration for monepantel in terms of the amount of sulfone metabolite generated. Because monepantel sulfone is the main chemical entity present in sheep blood after monepantel administration and because it is also an active metabolite, its pharmacokinetic properties are of primary importance for the interpretation of future residue and efficacy studies. Overall, these pharmacokinetic data aid in the evaluation of monepantel as an oral anthelmintic in sheep.

Dose determination studies for monepantel, an amino-acetonitrile derivative, against fourth stage gastro-intestinal nematode larvae infecting sheep.

Monepantel is the first compound from the recently discovered amino-acetonitrile derivative (AAD) class of anthelmintics to be developed for use in sheep. Three dose determination studies were conducted in Australia and Switzerland to identify the minimum therapeutic dose of monepantel when formulated for the oral treatment of sheep to control fourth stage (L4) gastro-intestinal nematode larvae. In each study, sheep infected with the target nematodes (selected from Haemonchus contortus, Teladorsagia (Ostertagia) circumcincta, Teladorsagia trifurcata, Trichostrongylus axei, Trichostrongylus colubriformis, Trichostrongylus vitrinus, Cooperia curticei, Cooperia oncophora, Nematodirus battus, Nematodirus filicollis, Nematodirus spathiger, Chabertia ovina and Oesophagostomum venulosum) were treated with either 1.25, 2.5 or 5.0 mg monepantel/kg liveweight. Following euthanasia and worm counting, efficacy was calculated against worm counts from untreated control groups. Monepantel proved highly effective at 2.5 and 5.0 mg/kg, but was only moderately effective against some nematode species (L4 stage) at 1.25 mg/kg. The results also confirmed that monepantel will effectively control L4 stages of nematodes resistant to at least some of the currently available broad-spectrum anthelmintic classes (macrocyclic lactone resistant strains were not included in the studies). It was concluded that 2.5 mg/kg would be a suitable minimum dose rate for a commercial product. No adverse events related to treatment with monepantel were detected.

Efficacy of a milbemycin oxime-praziquantel combination product against adult and immature stages of Toxocara cati in cats and kittens after induced infection.

Two studies were performed to examine the efficacy of milbemycin oxime against fourth-stage larvae or adults of Toxocara cati. In the study to determine efficacy against fourth-stage larvae, 20 domestic shorthair cats were inoculated with 500 embryonated eggs. Four weeks after inoculation, the animals were allocated to two groups, and cats in one group were treated with medicated tablets containing 4 mg milbemycin oxime and 10mg praziquantel (MILBEMAX) and cats in the other group with placebo tablets. Seven days after treatment the animals were euthanatized and necropsied for worm counting. The number of worms found was significantly (p=0.0002) lower in cats treated with medicated tablets than in cats treated with placebo tablets. The reduction in the number of worms was 96.53%. In the study to determine efficacy against mature adult worms, 13 kittens were inoculated with T. cati embryonated eggs. On day 45 after inoculation and after the infection had been confirmed through faecal examinations for 11 out of the 13 animals, the 11 infected animals were allocated to two groups and treated as in the first study. Seven days after treatment, all animals were euthanatized and necropsied for worm counting. The number of worms found was significantly (p=0.0043) lower in kittens treated with medicated tablets than in kittens treated with placebo tablets. The reduction in the number of worms was 95.90%. No adverse effects were recorded during either study. It is concluded that the milbemycin oxime-praziquantel tablets that were used are efficacious for the control of T. cati infections in cats.

Cell proliferation measurement in cecum and colon of rats using scanned images and fully automated image analysis: validation of method.

The purpose of this study was to establish and validate fully automatic measurement of cell proliferation on scanned images of rat cecum and colon. Tissue slides were taken from a 4-week mechanistic study and processed for BrdU immunohistochemistry. Four sections of the cecum and colon per slide were scanned with the Zeiss MIRAX SCAN and transferred to the Definiens eCognition Analyst LS5.0 system for evaluation. Two rule sets for automatic counting of BrdU-positive and negative nuclei from mucosal cells on the image tiles were created by Definiens, one for cecum, one for colon. For validation, manual counting of 16 randomly selected tiles from five different slides of colon and cecum was performed. Negative and positive cell nuclei were counted in each image tile by four different people. Comparison of results from manual counting with the automatic counting showed that the sum as well as single tile data and labeling index (LI) from automatic counting were within the range of manual counting results +/-10%. Automatic counting included only cell nuclei within the mucosa whereas muscularis and lymphoid tissue as well as wrinkles from tissue preparation were excluded. In addition, two data sets from automatic counting of the same image tile were compared: (1) data where image tiles with incorrect detection of mucosa were excluded from further calculation of LI and area, and (2) data where no visual check was performed and all measurements were included. Results were very similar for both data sets. The necessity of the manual correction may therefore be doubted.

Application of a coproantigen ELISA as an indicator of efficacy against multiple life stages of Fasciola hepatica infections in sheep.

At present diagnosis of true resistance and determination of drug efficacy in Fasciola hepatica infection rely solely on terminal experiments. The coproantigen ELISA (cELISA) has been reported previously as a sensitive and specific tool appropriate to detect treatment failure, and potentially drug resistance. Two studies were conducted to determine whether the cELISA was appropriate for on-farm efficacy and resistance testing in Australian Merino sheep. In Study 1 sheep were infected orally with 50 F. hepatica metacercariae on three occasions, twelve, six and two weeks prior to a single flukicide treatment with triclabendazole, closantel or albendazole. Sheep were sampled weekly for a further seven weeks prior to necropsy. Following effective treatment, no faecal antigen was detected from 1 week. When immature stages (≤6 weeks) survived treatment, coproantigen reappeared from 6 weeks post-treatment. Therefore, cELISA conducted 1-4 weeks after treatment will demonstrate obvious treatment failure against adult F. hepatica, but is not sufficiently sensitive to detect survival of immature fluke until these reach maturity. In study 2, fluke burdens of sheep necropsied 13 weeks post single infection were compared to fecal worm egg counts (FWEC) and cELISA at necropsy. Regression analysis demonstrated that cELISA correlated strongly with fluke burden, whilst FWEC correlated weakly with cELISA. The correlation between FWEC and fluke burden was also weak, although stronger than that of FWEC with cELISA. The cELISA is an appropriate tool for monitoring effectiveness of treatments against Fasciola hepatica if an adult infection is present, however when immature stages of the parasite are present it is not as reliable. Where immature parasites are present it is recommended that initial cELISA be followed with a secondary cELISA at least 6 weeks after treatment to ensure resistance to immature stages is detected. Further testing is justified for monitoring the effectiveness of control programs by detecting adult populations that have survived a treatment regime.

Effects of Benazepril on Survival of Dogs with Chronic Kidney Disease: A Multicenter, Randomized, Blinded, Placebo-Controlled Clinical Trial.

BACKGROUND: Chronic kidney disease (CKD) is an important cause of morbidity and mortality in dogs. OBJECTIVE: To evaluate the efficacy in prolonging survival and safety of benazepril administration to dogs with CKD. ANIMALS: Forty-nine client-owned dogs with CKD. METHODS: Dogs were randomized to benazepril (0.25 to <0.5 mg/kg) or placebo once daily for up to 2 years in a prospective, multicenter, blinded clinical trial. The primary endpoint variable was the renal survival time, defined as the time from inclusion in the study to the treatment failure endpoint of death or euthanasia or need for administration of parenteral fluids related to renal failure. RESULTS: No benefit of benazepril versus placebo was detected for renal survival time in all dogs; median (95% confidence interval (CI)) survival times were 305 (53-575) days in the benazepril group and 287 (152-not available) in the placebo group (P = .53). Renal survival times were not significantly longer with benazepril compared to placebo for subgroups: hazard ratios (95% CI) were 0.50 (0.21-1.22) with P = .12 for initial urine protein-to-creatinine ratio (UPC) >0.5, and 0.38 (0.12-1.19) with P = .080 for initial UPC >0.5 plus plasma creatinine ≤440 µmol/L. Proteinuria, assessed from the UPC, was significantly (P = .0032) lower after treatment with benazepril compared to placebo. There were no significant differences between groups for clinical signs or frequencies of adverse events. CONCLUSIONS AND CLINICAL RELEVANCE: Benazepril significantly reduced proteinuria in dogs with CKD. Insufficient numbers of dogs were recruited to allow conclusions on survival time.

Immunohistochemical study about the Flt-1/VEGFR1 expression in the gastrointestinal tract of mouse, rat, dog, swine and monkey.

Fms-like tyrosine kinase 1 (Flt-1) performs a subordinate effector role in mesenchymal angiogenesis and potentially serves an equally important functional role as a self-contained receptor in epithelial cells. In both endothelial cells and epithelial cells, Flt-1/vascular endothelial growth factor receptor 1 (VEGFR1) downstream signalling is involved in regulating cellular processes such as cytoskeletal changes and cellular survival protection. Cellular renewal of the gastrointestinal mucosa is based on these processes and might involve Flt-1/VEGFR1 pathway activities; the molecular mechanisms regulating these cellular dynamics remain unclear. This study was performed to investigate the presence and distribution of Flt-1/VEGFR1 in epithelial cells of the gastrointestinal tract by immunohistochemistry (IHC). Gastrointestinal tissues were taken from eight anatomical sites from mouse, rat, dog, swine and monkey. Present results revealed a cytosolic Flt-1/VEGFR1 staining pattern in mucosal epithelial cells for all investigated species. Non-epithelial structures also displayed a distinct Flt-1/VEGFR1 positivity and included vascular smooth muscle walls, enteric smooth muscle layers, the enteric nervous system and capillary endothelial cells. Diverse intensities of the Flt-1/VEGFR1 binding reaction within each species were observed in the intestinal mucosa with a strong immunoreaction in enterocytes and with a low protein expression in the ileum in most species. Crypt cells in the large intestine were mostly negative for Flt-1/VEGFR1. A peculiar and mainly intranuclear antibody binding reaction was found in Brunner's gland epithelial cells of mouse and rat whereas Brunner's glands of dog, swine and monkey remained completely negative. These results indicate a potential involvement of Flt-1/VEGFR1 in normal restitution of gastrointestinal structures in the species studied. Additionally, intranuclear Flt-1/VEGFR1 antibody binding in Brunner's glands of rodents may suggest a nuclear translocation of the transmembrane VEGFR1 which has not previously been described.

Evaluation of the efficacy of oral lufenuron combined with topical enilconazole for the management of dermatophytosis in catteries.

The efficacy of oral lufenuron, a chitin synthetase inhibitor, combined with topical enilconazole, was evaluated for the management of Microsporum canis infection in 100 cats housed in two catteries in France. The cats were treated with weekly rinses with enilconazole (0.2 per cent) for four weeks and, in each cattery, one group (A) was also treated with micronised griseofulvin (25 mg/kg administered orally twice a day for five weeks) and a second group (B) was treated with 60 mg/kg lufenuron administered orally once on day 0 and again after 30 days. All the cats were examined individually for cutaneous lesions and mycological cultures were made when the treatment began and after 15, 30, 60 and 90 days. In the first cattery, the cats' clinical scores after 30 and 60 days were significantly lower in group B than in group A. In both catteries and both treatment groups, the mean number of fungal colonies decreased rapidly during the first 15 days of treatment, remained stable for the following 45 days but increased from day 60 to the end of the experiment on day 90.

Efficacy of Milbemax (milbemycin oxime + praziquantel) in the treatment of dogs experimentally infected with Crenosoma vulpis.

Crenosoma vulpis, the fox lungworm, infects wild and domestic canids and is a cause of chronic respiratory disease in dogs in North America and Europe. The objective of this study was to determine the efficacy of milbemycin oxime (0.5mg/kg)/praziquantel (5mg/kg) (Milbemax; Novartis Animal Health, Inc.) against C. vulpis infection in a randomized, blinded, placebo-controlled study using experimentally infected dogs. Sixteen beagles (8 males, 8 females) were each given 100 infective third-stage larvae of C. vulpis. Fecal samples were examined for first-stage larvae by quantitative Baermann examination pre-exposure and at days 21, 28, 35, 42 and 49 post-infection (PI). All of the dogs were shedding larvae in the feces at 21 days PI. The dogs were randomly assigned to one of two groups. At 28 days PI, Group 1 (4 males, 4 females) received placebo only while Group 2 (4 males, 4 females) received a single treatment of milbemycin oxime (0.5mg/kg) and praziquantel (5mg/kg). The 16 dogs were euthanized and necropsied at 49 days PI. Lungs were removed, assessed for gross lesions (graded on a subjective scale 0-3 with 0 being normal) and C. vulpis were collected by lung-flush and counted. Samples of lung tissue were preserved for evaluation of histopathology and the lesions graded on a subjective scale (0-3 with 0 being normal). Gross and histopathology lesions were detected in all 8 untreated Group 1 dogs with mean subjective lesion scores of 1.8 ± 0.7 (range 1-3) and 3.0 ± 0.0 (range 3), respectively. Gross lesions were observed in 3/8 and histopathology lesions in all 8 of the treated Group 2 dogs with mean subjective lesion scores of 0.4 ± 0.5 (range 0-1) and 1.3 ± 0.4 (range 1-2), respectively. The mean (geometric) number for adult C. vulpis recovered in untreated dogs was 48.3 (range 25-70) compared with 0.65 (range 0-2) in animals treated with Milbemax. The resulting efficacy against C. vulpis was 98.7%. The number of C. vulpis was significantly lower for treated dogs than the burden in the untreated group (p=0.0002). A single dose of Milbemax (milbemycin oxime 0.5mg/kg+praziquantel 5mg/kg) was highly effective for the treatment of patent C. vulpis infection in dogs. A dosing interval for the prevention of clinical disease in dogs exposed to natural infections has not been established.