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Background Pancreatitis in cats (FP) has been increasingly diagnosed in recent years, but clinical studies of large numbers of affected cats are scarce. Objectives To describe a large cohort of cats with FP requiring hospitalization. Animals One hundred and fifty-seven client-owned cats. Methods Retrospective study, including cats diagnosed with pancreatitis based on sonographic evidence, positive SNAP feline pancreatic lipase immunoreactivity test results, increased 1,2-o-dilauryl-rac-glycerol-glutaric Acid-(6'-methylresorufin ester)-lipase activity, histopathology, or some combination of these. Results One-hundred and twenty-two cats (77.7%) survived to discharge. Median time from onset of clinical signs to presentation was longer (P = .003) in nonsurvivors. Causes of FP included recent general anesthesia, trauma, hemodynamic compromise, and organophosphate intoxication, but most cases (86.6%) were idiopathic. Ultrasonographic findings consistent with pancreatitis were documented in 134 cats, including pancreatomegaly (81.3%), decreased (31.3%), or increased (14.9%) pancreatic echogenicity, extra-hepatic biliary tract dilatation (24%), and increased peri-pancreatic echogenicity (13%). Lethargy (P = .003), pleural effusion (P = .003), hypoglycemia (P = .007), ionized hypocalcemia (P = .016), azotemia (P = .014), parenteral nutrition administration (P = .013), and persistent anorexia during hospitalization (P = .001) were more frequent in nonsurvivors, whereas antibiotics were more frequently administered to survivors (P = .023). Nevertheless, when Bonferroni's correction for multiple comparisons was applied, none of the variables was statistically significant. Conclusions and clinical importance Previously unreported, clinically relevant, potential prognostic factors, including hypoglycemia, azotemia, parenteral nutrition, and withholding antibacterial treatment were identified in this exploratory study. These preliminary results should be examined further in confirmatory studies.

Objective To determine azithromycin concentration in severely inflamed canine external ear canals. Material and methods Five dogs of various breeds and ages with severe and chronic otitis externa underwent ear canal reconstruction surgery. A single oral dose of azithromycin at 10 mg/kg was administered 12 to 24 hours prior to surgery. Tissue samples were collected from the excised external ear canals and azithromycin concentration was determined using a liquid chromatography-tandem mass spectrometry method. Results Azithromycin concentrations ranging from 11.4 to 107.0 μg/g (mean 59.2 ± 44.6 μg/g, median 50.9 μg/g) were detected in the chronically infected external ear canal tissue 12 to 24 hours after administration. Clinical significance Little information exists on antibiotic concentrations in pathological tissues of dogs. Macrolides are known to concentrate in skin tissue. In light of the present results, investigation of clinical efficacy of azithromycin in chronic canine otitis externa is warranted.

Myiasis is a major disease condition in human and veterinary medicine. Domestic, free-ranging, and zoo-housed animals can be severely affected by myiasis. Depending on case severity, multiple treatment episodes may be indicated and can lead to recurrent capturing, handling stress, and anesthetics, all of which increase the risk of adverse responses (including death) individually and also in the herd. As an insecticide, ivermectin is often used for larval control. A total of 28 individual myiasis cases were retrospectively evaluated, out of which 11 cases were also treated using an ivermectin sustained-release varnish (SRV). The clinical outcome of all cases was assessed and the results suggest that the use of a topical ivermectin SRV (with or without concurrent injectable ivermectin) can reduce handling and treatments, has no adverse effects, and has minimal recurrence of the disease when compared with cases treated without it.

Domestic goats, although present in large numbers worldwide, are still considered a minor species in Europe and the USA. Due to their minor status, new therapies directed to relieve pain is a neglected area of investigation. Unfortunately there is a lack of approved drugs for this species and many drugs are administered in an extra-label manner. Often no information on the safety profile for goats and for humans consuming their products is available. Meloxicam (MEL) is a potent anti-inflammatory drug characterized by a preferential COX-2 isoenzyme inhibition. The aim of this study was to determine the pharmacokinetics of MEL at the dose of 0.5 mg/kg in lactating goats after intravenous (IV) and intramuscular (IM) administration and to quantify its residues in milk. The analytical method was performed by the HPLC diode array detector. The IV and IM administrations of MEL in lactating goats showed suitable pharmacokinetic profiles for this animal species. The IM route showed a bioavailability of 105% and long half-life of elimination (10.82 h). The simulation of multiple daily IM injections provides a plasma concentration above the therapeutic concentrations determined for other species for the majority of 24 h. The high IM bioavailability, the long half-life of elimination and the mean plasma concentration at the steady state suggested that once a day administration might be sufficient. MEL residues were quantifiable in milk up to 48 h in IM group and 60 h in the IV group. This data seems to be in line with the milk depletion reported in cattle. Further studies are necessary to establish if the minimal effective concentration determined in other animal species can be applied to goats too.

Background Acute pancreatitis (AP) is common in dogs. Nevertheless, validated clinical severity index (CSI) scoring systems to assess severity and guide treatment in current, large-scale studies are unavailable. Methods This is a retrospective study including 109 dogs. Pancreatitis was diagnosed based on clinical signs, abdominal sonographic evidence, positive pancreatic lipase assays and experts’ assessment consensus. Results The survival rate was 75 per cent (82 dogs). Azotaemia and presence of local complications (ie, ascites) and secondary complications (ie, acute kidney injury and acute respiratory distress syndrome) were significantly associated with death. In agreement with the previously published CSI, respiratory anomalies were significantly associated with death. However, in disagreement with that study, high scores in the kidney and local abdominal complication categories and the sum of scores of all nine categories, but not high gastrointestinal category score, were also significantly associated with death. A final CSI score of at least 4 was associated with death. Conclusions This study has validated a nine-category CSI, proven a useful assessment tool in dogs with AP. Several previously reported and novel prognostic markers were assessed.

This case-control retrospective study (years 2004-2009) investigated the epidemiological, clinical, and diagnostic test findings of dogs with esophageal spirocercosis (ES) presented to the Hebrew University Veterinary Teaching Hospital (HUVTH) and coproscopy-positive dogs at the Kimron Veterinary Institute (KVI), Israel. It included 133 dogs with ES and 133 negative controls diagnosed at the hospital, and 343 dogs diagnosed at the KVI. The average incidence of ES at the HUVTH was 22.5/year, and the percentage of spirocercosis cases was stable at both institutions (HUVTH, 0.67-1.23%; KVI, 5-8%). Dogs aged > 5 years old had 100-fold likelihood to be infected compared to dogs aged ≤ 1 year of age (P < 0.001). Mean body weight (P = 0.0004), proportion of Retrievers (P = 0.002) and sporting breed dogs (P = 0.006) were higher, while proportion of toy breeds (P = 0.004) was lower in the ES group compared to the control group. The proportion of cases from Greater Tel-Aviv decreased (P = 0.002), while that of those from Judea and Jerusalem increased (P = 0.01) compared to the 1990 s. Spirocercosis occurred in 22 dogs despite past prophylactic avermectin treatment. Vomiting and regurgitation were the most common clinical signs of ES. Coproscopy was S. lupi-positive in 33/60 dogs (55.0%). The median number of esophageal nodules was two (range 1-8), with a median diameter of 3.5 cm (range 1.0-11.0). Malignant esophageal lesion transformation was confirmed in 29 dogs (22%). Despite preventive attempts, spirocercosis has spread in Israel over time, compared to previous findings, raising questions about the efficacy of the currently accepted prophylactic protocol is incompletely effective.

Thiazolidinedione-8 (TZD-8) is an anti-quorum-sensing molecule that has the potential to effectively prevent catheter-associated urinary tract infections, a major healthcare challenge. Sustained-release drug-delivery systems can enhance drugs' therapeutic potential, by maintaining their therapeutic level and reducing their side effects. Varnishes for sustained release of TZD-8 based on ethylcellulose or ammonio methacrylate copolymer type A (Eudragit(®) RL) were developed. The main factors affecting release rate were found to be film thickness and presence of a hydrophilic or swellable polymer in the matrix. The release mechanism of ethylcellulose-based systems matched the Higuchi model. Selected varnishes were retained on catheters for at least 8 days. Sustained-release delivery systems of TZD-8 were active against Candida albicans biofilms. The present study demonstrates promising results en route to developing applications for the prevention of catheter-associated infections.

Catheter-associated urinary tract infections are difficult to eradicate or prevent, due to their biofilm-related nature. Chlorhexidine, a widely used antiseptic, was previously found to be effective against catheter-related biofilms. For the present study, we developed sustained-release chlorhexidine varnishes for catheter coating and evaluated their antibiofilm properties and chlorhexidine-dissolution kinetics under various conditions. The varnishes were based on ethylcellulose or ammonio methacrylate copolymer type A (Eudragit® RL). Chlorhexidine was released by diffusion from a heterogeneous matrix in the case of the ethylcellulose-based formulation, and from a homogeneous matrix in the case of Eudragit® RL. This dictated the release pattern of chlorhexidine under testing conditions: from film specimens, and from coated catheters in a static or flow-through system. Momentary saturation was observed with the flow-through system in Eudragit® RL-based coatings, an effect that might be present in vivo with other formulations as well. The coatings were retained on the catheters for at least 2weeks, and showed prolonged activity in a biological medium, including an antibiofilm effect against Pseudomonas aeruginosa. The current study demonstrates the potential of catheter coatings with sustained release of chlorhexidine in the prevention of catheter-associated urinary tract infections.

Thiazolidinediones (TZDs) have been found to act as effective quorum sensing quenchers, capable of preventing biofilm formation. Our previous studies demonstrated a profound antibiofilm effect of the TZD derivative thiazolidinedione-8 (S-8), either in solution or incorporated into a sustained-release membrane (SRM-S-8) under batch conditions. In the present study, we used a constant depth film fermenter model in order to investigate the impact of SRM-S-8 on mixedC. albicans-S. mutansbiofilm development, under flow conditions. We found that essential parameters of cospecies biofilm maintenance and maturation, such as metabolic activity, biofilm thickness, roughness, extracellular polysaccharides production, and morphology of both pathogens, were altered by SRM-S-8 in the flow system. We propose that prolonged and sustained release of S-8 in a flow-through system allows better penetration of the active agent to deeper layers of the mixed biofilm, thereby increasing its activity against both pathogens. In conclusion, the use of a locally applied sustained-release drug delivery system of S-8 can affect the dental polymicrobial biofilm, resulting in clinical improvements and a better patient compliance.

The parasitic nematode Spirocerca lupi causes major morbidity and mortality in dogs. The scarab beetle Onthophagus sellatus is its major intermediate host in Israel. We investigated the prevalence of beetle infection by S. lupi in different years between 1994 and 2008. The average monthly maximum and minimum relative humidity (RH) and ambient temperature (AT) throughout the study period were calculated based on daily meteorological data. The infection prevalence decreased over the study period, possibly due to a chronological change resulting from increased preventive treatment of dogs against S. lupi, or climate change. Multivariate analysis was performed for these two hypotheses. Under the first hypothesis, chronological change was forced into the model, and environmental variables were inserted stepwise. The final model included beetle-collection date, minimum RH (RH min) during the month preceding beetle collection, its interaction with maximal AT (AT max) during that same month, and the interaction of maximal RH (RH max) and AT max, during the month of beetle collection. Under the second hypothesis, chronological change was not forced. The final model included RH max during the month of beetle collection, average RH (RHave) during the month preceding beetle collection, and its interaction with AT max during the latter month. The results suggest that under both hypotheses, RH and AT during the month preceding beetle collection influence S. lupi's ability to develop and survive in O. sellatus, and may be used to predict the risk to dogs of S. lupi infection.

Serum and skin tissue azithromycin (AZM) concentrations were analysed in healthy and pyoderma affected dogs to determine AZM pharmacokinetics and to establish the effect of disease on AZM skin disposition. AZM was administered orally to two groups of healthy dogs: (1) at 7.02 mg/kg (n = 7) and (2) at 11.2 mg/kg (n = 9). A crossover design was used on five of them. Seven dogs with pyoderma were treated with AZM at 10.7 mg/kg. The two groups of healthy dogs received AZM once daily over three consecutive days and dogs with pyoderma received the same treatment repeated twice with an interval of 1 week. AZM concentrations were determined by liquid chromatography–tandem mass spectrometry. AZM was rapidly absorbed and slowly excreted. In healthy dogs, maximum serum concentrations appeared 2 h after administration and were (mean ± standard deviation) 0.60 ± 0.25 μg/mL and 1.03 ± 0.43 μg/mL, and the half-lives were 49.9 ± 5.10 and 51.9 ± 6.69 h for doses of 7.02 and 11.2 mg/kg, respectively. Clearance (CL0–24/F) was similar in both dosing groups (1.24 ± 0.24 and 1.29 ± 0.24 L/h/kg) and the respective mean residence time (MRT0–24) was 11.1 ± 0.8 and 8.4 ± 2.2 h. The skin concentration in healthy dogs was 3.5–6.5 and 5.0–12.0 times higher than the corresponding serum concentration after the two doses and increased after the cessation of AZM administration. The ratio increased significantly in inflamed tissue (9.5–26.2).

The pharmacokinetics of ampicillin in dogs was determined after intravenous (i.v.) bolus and constant rate infusion. Ampicillin was administered to six beagle dogs as an i.v. bolus at 20 mg/kg and as a constant rate i.v. infusion (CRI) at 20 mg/kg during 8 h (0.042 mL/min/kg) in Ringer's lactate (Hartmann's) solution. The concentrations were determined by an LC/MS/MS method. After i.v. bolus, ampicillin total body clearance, apparent volume of distribution at steady-state, mean residence time (MRT), and half-life were 4.53 ± 0.70 mL/min/kg, 0.275 ± 0.044 L/kg, 61 ± 13 min, and 111 (85-169) min, respectively. The corresponding parameters calculated after CRI were 13.5 ± 1.06 mL/min/kg, 0.993 ± 0.415 L/kg, 73 ± 27 min, and 49 (31-69) min. Ampicillin concentration decreased by 30% in the Ringer's lactate infusion solution mostly during the first hour after preparation of the solution. Constant rate infusion of Ringer's lactate solution during 8 h caused significant changes in ampicillin pharmacokinetics. The results suggested that special attention should be given to drug pharmacokinetics when co-administered intravenously with electrolyte solutions.

The objective of the present study was to assess the pharmacokinetics of the novel atypical drug tapentadol (TAP) after intravenous (I.V.) and intramuscular (I.M.) injections in clinically healthy goats. A 2 × 2 cross-over design study was carried out. Six local adult Nubian nonlactating, nonpregnant female goats, were given 5 mg/kg body weight of TAP by I.V. and I.M. routes. The concentrations of TAP in plasma were evaluated using a validated HPLC method. Transient adverse effects were noticed in some animals, especially after I.V. administration (tremors and ataxia). Three days after drug administration, severe hair loss was also recorded. The plasma concentrations after the two routes of administration were best described by a bi-compartmental model. After I.M. injection, TAP showed a very fast absorption (Tmax = 0.17 h) and a short half-life (1.29 h). The I.M. bioavailability was quite high, despite being variable (87.8 ± 35.6%). This is the first pharmacokinetic study of TAP in goats but due to its unknown safety profile and efficacy, it is premature to recommend the use of this drug in clinical ovine practice.

Ureteral stents are being used exceedingly in the field of urology, and with advancements in endourology, this trend is increasing. Bacterial colonization and proliferation on the stent surface may result in urinary tract infections (UTIs) necessitating the administration of antibiotics that, in turn, may lead to the development of antibiotic-resistant bacterial strains. Several studies have shown that sustained release varnish (SRV) combined with antibiotics or antiseptics can prevent the proliferation of bacteria on urethral catheters. This is the first study that evaluates this technique implemented on ureteral stents.We evaluated growth inhibition on ureteral stent segments coated with chlorhexidine (CHX) 1% SRV. The tests were conducted using common urinary pathogens: Enterococci, Pseudomonas, and Escherichia coli. Coated stent segments were inserted into bacterial suspensions. Controls included uncoated stent segments and stents coated with placebo SRV (without CHX).Bacterial growth measured as turbidity and as colony-forming units showed a significant inhibition effect of initial bacteria adhesion to the CHX-SRV coated stent segments compared with the controls (P0.001). This inhibitory effect was apparent in each of the bacteria tested and was confirmed by inspection of the stent segments under an electron microscope. In a kinetic experiment using CHX 2% SRV, we were able to prolong the growth inhibition effect from 1 week to nearly 2 weeks.We believe this technique may play a significant role in reducing ureteral stent-associated UTIs. Further studies are needed before this approach can be implemented in clinical practice.

During the past decade, the incidence of severe infections after transrectal ultrasonography-guided prostate biopsy has increased. Antibacterial sustained-release varnish has been shown to reduce bacterial infections. This varnish has yet to be tested in the field of urology. We undertook an in vitro study to assess the possibility of reducing infection rates after prostate biopsy by coating the needle with a novel sustained, yet rapid release chlorhexidine varnish (SRV-CHX) specifically modified for prostate biopsy.A model simulating the microbiologic environment of a prostate biopsy was developed. The model consisted of two layers of agar, of which the first represented the rectum and was preinfected with Escherichia coli. The second layer was sterile and represented tissue interposed between the rectum and prostate. SRV-CHX-coated biopsy needles were inserted 12 times through the two layers, into the third agar layer representing the prostate. Infection transmission was determined by assessing bacterial growth at inoculation sites within the agar plate representing the prostate. Bacterial growth inhibition was measured as an inhibition zone on the contaminated agar.Testing the antibacterial effect of the SRV-CHX-coated needle, we found a substantial reduction of infection transmission as well as sustained inhibition of bacterial growth compared with control needles.Needles coated with SRV-CHX offer a new strategy in infection control after prostate biopsy. A new strategy of SRV-coated prostate biopsy needles supplemented with various antibacterial agents, combined with prophylactic oral antibiotics should result in decreased infection rates after prostate biopsies. Further in vitro studies are needed to formulate the SRV with an optimal antibacterial agent.

Background Relapsing fever (RF) is an acute infectious disease caused by arthropod-borne spirochetes of the genus Borrelia. The disease is characterized by recurrent episodes of fever that concur with spirochetemia. The RF borrelioses include louse-borne RF caused by Borrelia recurrentis and tick-borne endemic RF transmitted by argasid soft ticks and caused by several Borrelia spp. such as B. crocidurae, B. coriaceae, B. duttoni, B. hermsii, B. hispanica and B. persica. Human infection with B. persica is transmitted by the soft tick Ornithodoros tholozani and has been reported from Iran, Israel, Egypt, India, and Central Asia. Methods During 2003–2015, five cats and five dogs from northern, central and southern Israel were presented for veterinary care and detected with borrelia spirochetemia by blood smear microscopy. The causative infective agent in these animals was identified and characterized by PCR from blood and sequencing of parts of the flagellin (flab), 16S rRNA and glycerophosphodiester phosphodiestrase (GlpQ) genes. Results All animals were infected with B. persica genetically identical to the causative agent of human RF. Phylogenetic analysis indicated that DNA sequences from these pet carnivores clustered together with B. persica genotypes I and II from humans and O. tholozani ticks and distinctly from other RF Borrelia spp. The main clinical findings in cats included lethargy, anorexia, anemia in 5/5 cats and thrombocytopenia in 4/5. All dogs were lethargic and anorectic, 4/5 were febrile and anemic and 3/5 were thrombocytopenic. Three dogs were co-infected with Babesia spp. The animals were all treated with antibiotics and the survival rate of both dogs and cats was 80 %. The cat and dog that succumbed to disease died one day after the initiation of antibiotic treatment, while survival in the others was followed by the rapid disappearance of spirochetemia. Conclusions This is the first report of disease due to B. persica infection in cats and the first case series in dogs. Infection was associated with anemia and thrombocytopenia. Fever was more frequently observed in dogs than cats. Domestic canines and felines suffer from clinical disease due to B. persica infection and may also serve as sentinels for human infection.

Biofilms on the surfaces of urinary catheters are among the pivotal factors for recurrent and persistent infections in urology. Many techniques have been investigated and applied for eradication of these biofilms--but with no full success. The aim of this study was to examine the effect of sustained release medicated varnish, releasing chlorhexidine, on the formation of biofilm on the urinary catheter surface in an in-vitro model.A batch model was used to test the antibacterial/antibiofilm effect of the sustained release varnish: Catheter pieces coated with sustained release varnishes were placed in bacterial growth medium that was infected with Pseudomonas aeruginosa for 96 hours. Various concentrations of chlorhexidine impregnated in the varnish were tested. After the incubation period, the catheter pieces were assessed for biofilm formation by measuring the optical density, colony-forming units, and using confocal laser scanning microscopy, and electron scanning microscopy.Biofilm growth measurement (colony-forming units [CFU]) on the catheter surface coated with the various concentrations of chlorhexidine in sustained released varnish revealed a 94% reduction with 1% chlorhexidine (P0.0001) and 43% reduction with 0.1% chlorhexidine (P=0.08) coated varnish in comparison with a positive control or the placebo varnish in preventing biofilm growth of P. aeruginosa. These biologic assays were confirmed using confocal and electron microscopy.Of the various tested concentrations of sustained release varnishes, the 1% chlorhexidine concentration has demonstrated the superior antibiofilm effect on urinary catheters with P. aeruginosa. Although similar varnishes are used in dentistry, it needs extended research in animals before applying this technology in human trials.

Spirocerca lupi is a parasitic nematode of dogs, that causes significant morbidity and mortality. Its intermediate hosts in Israel have never been described. The aim of this study was therefore to identify the intermediate hosts of S. lupi in Israel and to describe their abundance and annual infection rate with the nematode, in different microenvironments (i.e., the effects of irrigation and shade) in an endemic area. Dog dung pads were collected every 2 months from two different public parks for 1 year. Dung beetles were identified to the species level in infested dog feces and were examined for the presence of S. lupi larvae through dissection. The Scarabid beetle Onthophagus sellatus was the most abundant dung beetle species in dog dung pads and the only one infected with S. lupi larvae. The minimal period for development of the S. lupi L3 infective stage was 7 days. Significant differences were observed between the two different microenvironments and along the year. The highest risk for infection of dogs with the nematode was during the summer, in an irrigated, shady microenvironment.

Background: Spirocerca lupi is a nematode of Canidae that matures within the esophageal wall to form fibroblastic nodules with potential for malignant transformation. Diagnosis is based on histopathologic examination, but false-negative results may be obtained from samples collected by endoscopy. Serum alkaline phosphatase (ALP) activity, frequently increased in hepatobiliary disease, is also increased in a variety of neoplastic conditions in dogs, including appendicular osteosarcoma, and has also been reported to be increased in dogs with spirocercosis. Objective: The aim of this study was to evaluate serum ALP activity as a marker for malignant transformation of esophageal nodules in S. lupi-infected dogs. Methods: In this retrospective study, medical records of dogs diagnosed with spirocercosis from 1991 to 2008 were reviewed, and serum ALP activity determined at presentation was compared between dogs with nonneoplastic and neoplastic nodules. Owing to use of multiple analyzers, ratios of ALP activity to the upper reference interval for ALP were calculated and compared. Results: Median ALP activity ratios were 0.65 (0.07–4.00) and 0.86 (0.10–3.40) for dogs with nonneoplastic (n=88) and neoplastic (n=32) nodules, respectively, with no significant difference (P=.18) and substantial overlap between groups. Tumors included osteosarcoma (15 dogs), fibrosarcoma (15 dogs), and anaplastic sarcoma (2 dogs); there was no difference in ALP activity between the dogs with osteosarcoma and fibrosarcoma. Conclusion: ALP is a poor marker of malignant transformation in canine spirocercosis.

Feline lower urinary tract diseases in general, and urethral obstruction (UO) in particular, are common clinical conditions in cats. The aims of this study were to identify risk factors for UO, to characterise clinical and clinicopathological signs, outcome and recurrence, as well as risk factors for mortality and recurrence. Eighty-two cats with UO were compared to 82 sex and time matched controls. The mean age of cats with UO was significantly lower compared to controls, while the mean body weight was higher. The proportion of indoors–outdoors cats was significantly lower in the study group compared to the control group, and the proportion of cats consuming only dry food was higher. Overall mortality was 8.5%. Ionised calcium was significantly higher in survivors compared to non-survivors, and the prevalence of hypocalcaemia was lower. Recurrence in 6 months and 2 years were 22% and 24%, respectively. Cats with recurrence had significantly lower urine pH at presentation.

Beta-lactam antimicrobials, commonly used in both veterinary and human medicine, generally present short biologic half-lives, whereas their activity is enhanced as pathogen exposure is prolonged. These properties necessitate multiple-dose regimens of standard dosage forms, thereby hampering pet owner adherence, frequently resulting in therapeutic failure. This study presents a novel controlled-release gastroretentive oral drug delivery system for beta-lactams with which single-dose administration provides an effective antimicrobial course, optimizing pharmacokinetic (PK)-pharmacodynamic (PD) profiles, minimizing adverse effects and emergence of antimicrobial resistance and facilitating adherence. Our prototype sustained-delivery swelling-tablet (SDST), based on a degradable hydrophilic polymeric matrix, was designed to enable continuous input of these drugs to their absorption sites over several days. Several SDST formulations of the beta-lactam amoxicillin were evaluated in in vitro dissolution studies. Two formulations were selected for further in vivo canine studies, for determination of gastric retention and PK-PD profiling. Prolonged gastric retention times maintaining allowed for maintained effective drug concentrations against many clinically relevant pathogens for more than 48 h for one formulation and more than 5 days for the other. Both SDST formulations offer significant advantages over standard immediate-release therapy in achieving PK-PD goals and enhancing adherence. The prototypical formulations represent a novel platform which may be modified to meet various clinical requirements.

Dosage forms of antimicrobials play a critical role in facilitating the attainment of pharmacokinetic-pharmacodynamic (PK-PD) targets as well as adherence in both veterinary and human medicine. The purpose of this study was to develop and evaluate a controlled-release subcutaneous amoxicillin implant for single-dose therapy of large ruminants such as goats, sheep, and deer. The degradable implant, designed to attain PK-PD targets following single administration, was evaluated for amoxicillin release rate and time-concentration profile. In vitro release studies demonstrated constant-rate release of approximately 40% of amoxicillin content within 96 h. In an in vivo study in goats, serving as a model for target animals, a serum concentration of approximately 0.4 mg/L was achieved within 8 h of implant insertion and maintained for >6 days. In comparison, in control goats given a standard single intramuscular amoxicillin dose of 15 mg/kg, amoxicillin peaked at 1.2 mg/L after 1 h, rapidly dropping to below detection level at 8 h. These results suggest that the proposed implant offers a unique modality for animal caregivers to conveniently administer a full antimicrobial course following a single dose of an efficient PK-PD-optimized dosage form. Furthermore, modifications of implant composition may allow for tailoring of its characteristics to various PK, PD, microbiological, and clinical requirements.

Britzi, M., Gross, M., Lavy, E., Soback, S., Steinman, A. Bioavailability and pharmacokinetics of metronidazole in fed and fasted horses. J. vet. Pharmacol. Therap. 33, 511–514. Metronidazole (1-[2-hydroxyethyl]-2-methyl-5-nitroimidazole) is a bactericidal antimicrobial agent used for treatment of infectious diseases caused by anaerobic bacteria and protozoa. Pharmacokinetics of metronidazole following its administration to horses was previously described (Sweeney et al., 1986; Baggot et al., 1988; Specht et al., 1992; Steinman et al., 2000). The bioavailability (F) was 85% (ranging from 57% to 105%) and the time to reach maximum serum concentration (tmax) was 1–2 h after oral dose at 25 mg/kg body weight (Sweeney et al., 1986). Baggot et al. (1988) found that F was 74.5% (ranging from 58.4% to 91.5%) and tmax was 1.5 h after oral dose at 20 mg/kg body weight. Specht et al. (1992) reported that F was 97% (ranging from 79% to 111%) and tmax was 40 min after oral dose at 15 mg/kg body weight. In an earlier study by our group F was 74% and tmax was 65 min after oral dose at 20 mg/kg body weight (Steinman et al., 2000). These individual variations in F might be partially explained by the effect of feed, among other factors, mainly on metronidazole absorption. Interactions between food and drugs may reduce or increase the drug effect. The majority of clinically relevant food–drug interactions are caused by food-induced changes on the bioavailability of the drug (Schmidt & Dalhoff, 2002). In dogs, absorption of metronidazole is enhanced when given with food, but delayed in humans (Plumb, 1995). Although, metronidazole is used commonly to treat various clinical conditions in horses with relatively little adverse effects (Sweeney et al., 1991), narrow margin of safety was suggested because histological evidence of peripheral neurotoxicity and hepatotoxicity were noted in horses treated with doses as low as 30 mg/kg body weight every 12 h orally for 30 days (White et al., 1996). For drugs with a narrow therapeutic index, even small changes in dose–response effects can have significant consequences (Schmidt & Dalhoff, 2002).

Guaifenesin is a very commonly used and prescribed oral expectorant drug. However, its mechanism of action is not completely elucidated and the available information is limited. The purpose was to evaluate whether guaifenesin action on respiratory tract secretion is mediated through a reflex stimulation of the gastric mucosa or by the systemic exposure due to the absorption of the drug to the blood circulation.Guaifenesin was administered to rats by various routes: intravenous bolus, oral gavage, and gastric, jejunal or cecal infusions (through surgically implanted catheters). Phenol red respiratory tract secretion (after intraperitoneal or intravenous injection) was used as a marker for degree of expectorant action. Administration of saline by gavage was used as control.Respiratory secretion following oral bolus was approximately 2-fold higher (p0.05) than that of control. Following IV administration the increase of respiratory secretion did not occur despite the fact that systemic exposure to guaifenesin was 1.5-fold higher than following oral administration. The abdominal surgery was found to eliminate the effect of guaifenesin although it did not change systemic absorption. Guaifenesin was equally absorbed from all parts of the gastrointestinal tract.It was demonstrated that expectorant action of guaifenesin is mediated by stimulation of the gastrointestinal tract and not by the systemic exposure to the drug.

A histological grading system of oesophageal sarcomas has not been established. Thirty-two cases of oesophageal sarcomas have been reviewed for tumour characteristics and clinical outcome. Nineteen dogs underwent surgical intervention to remove oesophageal tumours; ten of them survived (median 278 days). Primary tumour types included osteosarcoma (47%), osteosarcoma with tumour giant cells (7%), fibroblastic osteosarcoma (13%), chondroblastic osteosarcoma (7%) fibrosarcoma (23%) and undifferentiated sarcoma (3%). Histological grade evaluation revealed 33% grade 1 sarcoma, 50% grade 2 and 17% grade 3. No correlation could be found between survival and signalment, duration of clinical signs, tumour type, tumour grade and chemotherapy. Chemotherapy was found to reduce lung metastases' histological scores in three cases (P=0.0007). Surgery seems to be the treatment of choice but the effect of chemotherapy warrants further investigation. Additional research of cases should be performed in order to further define prognostic factors of oesophageal sarcomas.

Spirocerca lupi (Nematoda, Spirurida) is a life-threatening parasitic nematode of dogs that is presently emerging in several countries. Nonetheless, canine spirocercosis is neglected and underestimated, mainly due to diagnostic limitations inherent to clinico-pathologic, diagnostic imaging and laboratory methodologies. Given the significant benefit of improved diagnosis, the present work evaluated the reliability of a recently described copromicroscopic approach, the FLOTAC technique, as well as a PCR-based assay with that of traditional coproscopic techniques to diagnose S. lupi infection. Ninety-four faecal field samples were collected from two endemic areas (i.e. 29 and 65 from Kenya and Israel, respectively) and processed using different coproscopic examination techniques. In particular, set I (Kenyan samples) comprised the modified flotation with Sheather's sugar solution and merthiolate-iodine-formalin technique, while set II (Israeli samples) comprised a flotation technique with zinc sulphate solution, a modified sugar flotation procedure and the FLOTAC method. All samples were also subjected to a semi-nested PCR protocol specific for a region internal to the mitochondrial cytochrome c oxidase subunit 1 gene of S. lupi. The coproscopic examinations showed low sensitivity and high variability, demonstrating the unreliability of the conventional methods for detecting S. lupi eggs. Nonetheless, the FLOTAC technique scored the highest number of positives and significantly higher number of S. lupi eggs per microscopic field compared to the other coproscopic methods. Additionally, of the coproscopically negative samples, 9 (45%) Kenyan and 21 (38.2%) Israeli samples scored molecularly positive using the PCR-based approach. The potential implications and perspectives for canine spirocercosis of these coproscopic and molecular diagnostic methodologies evaluated herein are discussed.

Canine spirocercosis is a life-threatening parasitosis caused by Spirocerca lupi (Nematoda, Spirurida) that is presently emerging in several countries. This study characterised an informative region within the mitochondrial (mtDNA) gene encoding for the cytochrome c oxidase subunit 1 (cox1) of S. lupi by Polymerase Chain Reaction (PCR)-coupled sequencing. Specimens from five different countries in Europe, Asia and Africa were examined and two different sequence variants of cox1 (i.e. haplotypes) were determined, displaying nucleotidic variation at 6 of 689 positions. All of these positions were invariable among all the parasite individuals from Europe (haplotype 1) and among the African and Asian individuals (haplotype 2), but differed between Europe and Asia/Africa. The S. lupi cox1 sequences were consistent with those of other common Spirurida previously reported at both nucleotidic and phylogenetic levels. This study provides molecular information essential for identification of the nematode, irrespective of its life cycle stage. Crucial implications for the specific molecular diagnosis of clinical spirocercosis and investigation of the evolution, population genetics, ecology and epidemiology of S. lupi are discussed.

The records of five dogs diagnosed with spirocercosis-associated pyothorax were retrospectively reviewed. On admission, the most common clinical findings were weakness, anorexia, depression, dyspnoea and fever. All dogs had typical oesophageal Spirocerca lupi granulomas. Contrast thoracic radiography revealed contrast material leakage from the oesophagus into the pleural cavity in two dogs only. All dogs were medically treated with broad-spectrum antibiotics, repeated chest tube drainage and thoracic lavage, and four of the dogs were treated with doramectin. One dog was euthanased due to a concurrent non-related disease at the owners request while the remaining four survived. S. lupi infection should be included in the differential diagnoses of canine pyothorax in endemic areas. Conservative medical management of pyothorax with antihelmintic medication was shown to be effective in the treatment of S. lupi-associated pyothorax.

The nematode Spirocerca lupi infects dogs and is endemic in Israel. It leads to formation of esophageal nodules and neoplasia. Infection is diagnosed by coproscopy, endoscopy and radiography. Dirofilaria immitis causes heartworm disease in dogs, and has a world-wide distribution, but autochthonous infection has never been detected in Israel. Infection is confirmed based on identifying D. immitis microfilariae, in concentrated blood specimens by microscopy (Knott’s test or other tests) and serological tests specifically detecting circulating adult worm antigens. In the first part of this study, sera from dogs definitively diagnosed with esophageal spirocercosis by endoscopy were examined using three in-house immunoassays for detecting D. immitis antigen, and were positive in 2/19 (10.5%), 5/35 (14.3%) and 14/48 (29.2%) dogs, in assays 1 to 3, respectively, with no statistical difference between assays (P = 0.08). Next, sera from 32 additional dogs with confirmed esophageal spirocercosis, which were confirmed to be negative for D. immitis and Dirofilaria repens DNA using a sensitive high-resolution melt PCR were tested using assay 3 and 8/32 (25%) were positive. These results demonstrate serological cross-reactivity between D. immitis and S. lupi in blood samples of dogs. In areas where the distributions of both nematodes overlap, this cross-reactivity should be considered when dog are screened for heartworm disease.

This prospective, cross-over, blinded study evaluated the effect of various doses of phenylpropanolamine (PPA) on blood pressure in dogs. Dogs were randomized to receive a placebo or 1 of 3 dosages of immediate release PPA, q12h for 7 days [1 mg/kg body weight (BW), 2 mg/kg BW, or 4 mg/kg BW] in a cross-over design. Blood pressure was recorded every 2 h, for 12 h, on days 1 and 7. There were significant increases in systolic, diastolic, and mean blood pressure following administration of PPA at 2 mg/kg BW and 4 mg/kg BW. A significant decrease in heart rate was also noted at all PPA dosages, but not in the placebo. Administration of PPA was associated with a dose response increase in blood pressure. Dosages of up to 2 mg/kg BW should be considered safe in healthy dogs.

Seventeen client-owned dogs diagnosed with spirocercosis-associated esophageal sarcomas were retrospectively reviewed. The most common clinical signs noticed were vomiting and/or regurgitation (94%), lethargy and depression (59%), pyrexia and anorexia (41% each). Leukocytosis (82%) and microcytic hypochromic anemia (30%) were the most common hematological abnormalities. Caudal thoracic masses were demonstrated on survey radiographs of 13/15 of the dogs and thoracic spondylitis was detected in 12/15 dogs. Spirocerca lupi eggs were detected in 2/8 patients and worms were demonstrated on 1/11 at necropsy. Ten cases underwent surgical attempt to remove the tumors. In six of them partial esophagectomy (PE) was performed and all of them survived the immediate postoperative hospitalization. Five of the cases that underwent PE also received chemotherapy after surgery (doxorubicin (Adriamycin, Upjohn)) with an average survival time of 267 days. The histopathological results of the esophageal tumors were osteosarcoma (9), fibrosarcoma (5) and undifferentiated sarcoma (1). In areas endemic to spirocercosis, regurgitation or vomiting in dogs and microcytic hypochromic anemia and neutrophilia warrant ruling out esophageal sarcomas. Proper surgical treatment could prolong the dogs' lifespan for months, and improve their quality of life.

Spirocerca lupi is primarily a parasite of dogs, which typically causes oesophageal nodules, aortic aneurysms, and spondylitis. This study investigated the efficacy of doramectin as a prophylactic agent for canine spirocercosis. Five beagle dogs were injected subcutaneously with doramectin (400 μg/kg on 3 occasions 30 days apart q30d), while 5 other beagle dogs served as untreated controls. All dogs were inoculated with 40 infectious S. lupi larvae (L3) one month after the last doramectin treatment. All control dogs and 4/5 treated dogs became infected. Two control dogs died of ruptured aortic aneurysms, while no deaths occurred in treated dogs. Oesophageal nodules appeared 40–103 day later in treated as compared to control dogs, and eggs appeared in the faeces 49–106 day later in treated as compared to control dogs. The mean faecal egg count on day 223 in the treatment group was reduced by 99.77%. All control dogs had thoracic radiographic changes during the study, while only 2/5 study dogs showed radiographic changes. This study shows that although doramectin did not entirely prevent canine spirocercosis it reduced the clinical signs associated with infection and delayed and reduced egg output.

Expandable gastroretentive dosage forms (GRDFs) have been designed for the past 3 decades. They were originally created for possible veterinary use, but later the design was modified for enhanced drug therapy in humans. These GRDFs are easily swallowed and reach a significantly larger size in the stomach due to swelling or unfolding processes that prolong their gastric retention time (GRT). After drug release, their dimensions are minimized with subsequent evacuation from the stomach. Gastroretentivity is enhanced by the combination of substantial dimensions with high rigidity of the dosage form to withstand the peristalsis and mechanical contractility of the stomach. Positive results were obtained in preclinical and clinical studies evaluating GRT of expandable GRDFs. Narrow absorption window drugs compounded in such systems have improved in vivo absorption properties. These findings are an important step towards the implementation of expandable GRDFs in the clinical setting. The current review deals with expandable GRDFs reported in articles and patents, and describes the physiological basis of their design. Using the dog as a preclinical screening model prior to human studies, relevant imaging techniques and pharmacokinetic-pharmacodynamic aspects of such delivery systems are also discussed.

Purpose. To design novel expandable gastroretentive dosage forms (GRDFs) and evaluate their gastroretentive properties. Then, to assess the pharmacokinetics of levodopa compounded in such a GRDF in healthy volunteers. Methods. Thin (

The nematode Spirocerca lupi is a parasite of dogs with beetles of several species serving as intermediate hosts. The medical records of 50 dogs diagnosed with spirocercosis at the Hebrew University Veterinary Teaching Hospital (HUVTH) in Israel during 1991-1999 were retrospectively reviewed and compared to a control group (n=100). There was a seven-fold increase in the annual number of dogs diagnosed with spirocercosis during these years while the hospital caseload increased by 80%, indicating an emerging outbreak of this infection. Dogs from the greater Tel Aviv area were at the highest risk of being diagnosed with spirocercosis with 74% of the cases originating from this region compared to only 17% of the controls. The disease appeared to have a primarily urban pattern of distribution with a significantly higher percentage (P=0.025) of dogs from cities versus rural areas, as compared to the control group. Sixty-two percent of the cases were diagnosed during the colder months of December through April. The median age of infected dogs was 5 years, with dogs 1 year old or younger at the lowest risk of being diagnosed with spirocercosis. Large breeds were at a higher risk of infection in comparison to small breeds and the Labrador Retriever was significantly over represented (P=0.027) in the study group compared to the control population. The most common signs were vomiting or regurgitation (60%), pyrexia (24%), weakness (22%), respiratory abnormalities (20%), anorexia (18%), melena (18%) and paraparesis (14%). A caudal esophageal mass was identified by radiography in 53% of the dogs and spondylitis of the thoracic vertebrae in 33%. Fecal flotation was positive for S. lupi eggs in 80% of the dogs, and endoscopy was found to be the most sensitive diagnostic procedure and allowed diagnosis in 100% of the examined dogs. Fifty-three percent of the dogs were anemic and creatine kinase (CK) activities were elevated in 54%. Necropsy of 14 dogs revealed esophageal or gastric granulomas in 13 dogs, and an esophageal osteosarcoma in a single animal. Aortic aneurysms were found in six (43%) dogs. Out of 24, 15 dogs (63%) for which follow-up information was available died or were euthanized within 1 month of admission. The case-fatality rate decreased toward the end of the study period when improved therapy with avermectins became available.

Purpose. The purpose of this study was to design novel gastroretentive dosage forms (GRDFs) based on unfolding multilayer polymeric films, to investigate the mechanism of their gastroretentivity in dogs, and to assess the effect of compounding a narrow absorption window drug in a GRDF on the drug's absorption properties.

In November 2004, an adult male siamang (Hylobates syndactylus) from The Tisch Family Zoological Gardens-Jerusalem Biblical Zoo (Israel) presented with skin lesions on various body parts. Lesions consisted of alopecia and dry, crusty areas of hyperkeratosis. A diagnosis of dermatophytosis due to Microsporum canis was determined by fungal culture of skin scraping taken from the edge of several lesions. Treatment with various oral and topical antifungal agents such as griseofluvin, itraconozole, and lufenuron resulted in the resolution of most lesions and a decrease in size of the single remaining lesion, which continued to be culture positive for M. canis. The animal was anesthetized and an experimental sustained-release clotrimazole varnish was painted directly on the lesion. Initially there was no change in the lesion, and 2 months later a slightly altered formula was applied under anesthesia. One month later, the lesion began to reduce in size; 3 months after the start of treatment, although 2 years after the onset of clinical signs, the lesion resolved. Minimizing the number of treatments is always an advantage when dealing with exotic animals or zoological collections.

This paper describes five naturally occurring clinical cases of infectious canine cyclic thrombocytopenia that were the first serologically confirmed cases of Ehrlichia platys infection in Israel. In the USA this disease is considered subclinical, but the dogs in this study developed distinct clinical abnormalities. The signs observed by the owners included anorexia, lethargy, depression, weight loss and a mucopurulent nasal discharge. The principal findings on physical examination included lymphadenomegaly, pale mucous membranes, fever and the presence of ticks. The main abnormal haematological and biochemical findings included thrombocytopenia, the presence of giant platelets, low haematocrit, monocytosis and low albumin concentrations. All five dogs were less than two years of age, and four were purebred dogs, suggesting that these two factors may be associated with increased risk to infection and clinical disease. Two of the dogs were seropositive to E canis, a finding which is compatible with other reports, and which confirms that combined infections of E platys and E canis are common; it also suggests that E canis infections may contribute to the pathogenesis of E platys. The distinct clinical manifestation of the disease in these five dogs suggests that there may be a different, more virulent strain of E platys in Israel.

Spirocerca lupi, the dog esophageal worm, typically induces formation of esophageal nodules, which may transform to sarcoma. Ante mortem discrimination between benign and malignant esophageal masses is challenging. Serum acute phase proteins (APPs) are utilized in diagnosis and prognosis of various canine diseases as markers of inflammation. This study characterized serum APPs concentrations in dogs with benign and malignant esophageal spirocercosis and evaluated their accuracy in differentiating benign from malignant lesions. Seventy-eight client-owned dogs with esophageal spirocercosis were included. Serum C-reactive protein (CRP), haptoglobin, serum-amyloid A (SAA) and albumin concentrations were measured upon diagnosis and follow-up visits, and compared with healthy dogs, and between malignant and benign cases. Haptoglobin, CRP and SAA concentrations were higher, and albumin concentration was lower (P

The aim of this study was to develop and characterize floating stomach-retentive matrix tablets that will deliver polyphenols in a controlled release manner. The tablets were prepared by direct compression. A number of polymers were examined and egg albumin was chosen in light of a better performance in terms of floating behavior and decomposition time. Dissolution studies for three representative polyphenols loaded into a number of formulations were performed using the "f₂" factor in order to compare release profiles of different polyphenols and formulations. The release data showed a good fit into the power law equation and zero-order kinetics has been determined for some of the systems. Erosion and textural analysis studies revealed that higher concentration of egg albumin results in a higher gel strength that is less susceptible to erosion, potentially leading to a prolonged delivery time of drug. The ability of egg albumin-based tablets to resist high mechanical forces was also determined, while comparison to cellulose-derived polymers revealed that the latter have a much lower ability to resist the same forces. The developed delivery system has the potential to increase the efficacy of the therapy for various pathological stomach conditions and to improve patient compliance.

Cefixime is a unique third-generation oral cephalosporin. Its in vitro activity and pharmacokinetic properties have been studied to assess its potential for use in the therapy of newborn calf infections due to gram-negative bacteria. The minimum inhibitory concentrations of cefixime for 90% (MIC90) of field isolates of Escherichia coli, Salmonella and Pasteurella were 0.10-0.40 micrograms/mL. The serum disposition kinetics of cefixime following intravenous and oral administration was evaluated. The elimination half-life of cefixime after intravenous and oral administration was 3.5-4.0 h, the steady-state volume of distribution was 0.34 L/kg and approximately 90% of the drug was bound to serum proteins. Oral absorption was comparatively slow and bioavailability values for single 5 mg/kg doses were 20.2% after the administration of 200 mg of cefixime in capsules, 28.3% after dosing an aqueous solution of cefixime and 35.7% after fasted calves received the solution of cefixime. Mean serum drug concentrations 12 h after the cefixime solution was administered orally (5 mg/kg) were 1.05 micrograms/mL for the milk-fed calves and 1.76 micrograms/mL for the fasted calves. Computations showed that mean free drug concentrations equal to the MIC50 of the drug for gram-negative pathogens associated with newborn calf infections can be maintained in tissues by multiple treatments at 5 mg/kg every 12 h or 10 mg/kg every 24 h.

The disposition kinetics of intravenously (i.v.) administered amoxycillin sodium (10 mg/kg) was determined in four adult donkeys. The elimination half-life (t1/2 beta) of 47.3 +/- 5.1 min, the apparent volume of distribution (Varea) of 0.325 +/- 0.093 l/kg and the total body clearance (ClB) of 4.76 +/- 1.33 ml/min.kg were very close to the corresponding values reported for the horse injected i.v. with amoxycillin sodium. It was evident that because of the rapid rate of drug elimination, limited distribution volume, and high clearance values, the i.v. injected amoxycillin sodium (10-20 mg/kg) was likely to result in potentially therapeutic tissue concentrations for a short time (2-3 h) only. Three formulations of 15% amoxycillin trihydrate suspension in oil were injected intramuscularly (i.m.) to each donkey at 10 mg/kg. Drug absorption was rapid and the elimination half-life (t1/2el) ranged between 6 and 10 h. Mean peak serum amoxycillin concentrations (Cmax) were, however, rather low (0.81-1.68 micrograms/ml) and the i.m. bioavailability was 25.8-45.1% for the different formulations. Although the three formulations were considered to be intramuscularly bio-equivalent and appeared to be well tolerated, it was estimated that multiple SID (once daily) treatments at 10-20 mg/kg could result in tissue concentrations of potential therapeutic value for the treatment of infections caused by very susceptible pathogens only.

Background The parasitic nematode Spirocerca lupi (Spirurida: Thelaziidae), the canine esophageal worm, is the causative agent of spirocercosis, a disease causing morbidity and mortality in dogs. Spirocerca lupi has a complex life cycle, involving an obligatory coleopteran intermediate host (vector), an optional paratenic host, and a definitive canid host. The diagnosis of spirocercosis is challenging, especially in the early disease stages, when adult worms and clinical signs are absent. Thus, alternative approaches are needed to promote early diagnosis. The interaction between nematodes and their bacterial symbionts has recently become a focus of novel treatment regimens for other helminthic diseases. Results Using 16S rDNA-based molecular methods, here we found a novel bacterial symbiont in S. lupi that is closely related to Comamonas species (Brukholderiales: Comamonadaceae) of the beta-proteobacteria. Its DNA was detected in eggs, larvae and adult stages of S. lupi. Using fluorescent in situ hybridization technique, we localized Comamonas sp. to the gut epithelial cells of the nematode larvae. Specific PCR enabled the detection of this symbiont's DNA in blood obtained from dogs diagnosed with spirocercosis. Conclusions The discovery of a new Comamonas sp. in S. lupi increase the complexity of the interactions among the organisms involved in this system, and may open innovative approaches for diagnosis and control of spirocercosis in dogs.

Background Biofilm formation occurs commonly on urinary catheters. Objectives To assess the efficacy of urinary catheters coated with sustained-release varnish of chlorhexidine in decreasing catheter-associated biofilm formation in dogs. Animals Thirty client-owned dogs. Methods Prospective study. Thirteen dogs were catheterized with urinary catheters coated with sustained-release varnish of chlorhexidine (study group), and 13 dogs were catheterized with an untreated urinary catheter (control group). Presence and intensity of biofilm formation on the urinary catheters were assessed and compared between the groups by evaluating colony-forming units (CFU) of biofilm bacteria, and semiquantitatively, using confocal laser scanning microscopy and electron microscopy. Results None of the dogs experienced adverse effects associated with the presence of the urinary catheters. Median CFU count of biofilm bacteria at all portions of the urinary catheter was significantly (P