Postoperative integrity of veterinary surgical gloves

A multicenter, prospective study was performed to document the incidence of defective gloves postoperatively in veterinary surgery and to correlate defects with a variety of influencing factors. Gloves were collected after surgical procedures performed by the small animal clinical services at two veterinary teaching hospitals and one institution's student surgery laboratories. Gloves were evaluated for defects using electrical resistance testing. The overall incidence of glove defects was 23.3%. Significantly more defects occurred in gloves used for nonsoft-tissue procedures and in gloves worn on the nondominant hand. Eighty-four percent of all defects occurred in procedures lasting >60 minutes. No differences were detected in the brands of gloves used nor among surgeons of different experience levels. The individuals performing the surgery were not able to accurately predict the presence of a defect in their gloves. Surgeons should remain alert for possible glove defects and consider measures such as changing gloves every 60 minutes or double-gloving to minimize potential complications.     

Identification of a new source of Campylobacter contamination in poultry: transmission from breeder hens to broiler chickens

Campylobacter jejuni, a foodborne pathogen closely associated with market poultry, is considered to be the most frequent agent of human gastroenteritis in the United States. The pathways involved in the contamination of poultry flocks, vertical transmission and/or horizontal transmission, are unclear. In this study, Campylobacter isolates from two independent commercial broiler breeder flocks, as well as from their respective progeny, were characterized and compared by PstI ribotype analysis and by DNA sequence analysis of the short variable region (SVR) of the flaA gene (flaA SVR). Campylobacter isolates originating from one set of breeder hens and the feces from their respective progeny demonstrated identical ribotype patterns as well as identical flaA SVR DNA sequences, thereby suggesting that these isolates were clonal in origin. Ribotype analysis of Campylobacter isolates from the second set of breeder hens and processed carcasses from their offspring resulted in two patterns. Sequence analysis placed these isolates into two closely related groups and one distant group, similar to the ribotype analysis. These results demonstrate that Campylobacter isolates from commercial broiler breeder flocks and from the respective broiler progeny may be of clonal origin and that breeder hens can serve as a source for Campylobacter contamination in poultry flocks.     

Pharmacokinetics after intravenous and oral administration of enrofloxacin in sheep

OBJECTIVE: To compare pharmacokinetics of enrofloxacin administered IV and in various oral preparations to ewes. ANIMALS: 5 mature Katahdin ewes weighing 42 to 50 kg. PROCEDURE: Ewes received 4 single-dose treatments of enrofloxacin in a nonrandomized crossover design followed by a multiple-dose oral regimen. Single-dose treatments consisted of an IV bolus of enrofloxacin (5 mg/kg), an oral drench (10 mg/kg) made from crushed enrofloxacin tablets, oral administration in feed (10 mg/kg; mixture of crushed enrofloxacin tablets and grain), and another type of oral administration in feed (10 mg/kg; mixture of enrofloxacin solution and grain). The multiple-dose regimen consisted of feeding a mixture of enrofloxacin solution and grain (10 mg/kg, q 24 h, for 7 days). Plasma concentrations of enrofloxacin and ciprofloxacin were measured by use of high-performance liquid chromatography. RESULTS: Harmonic mean half-life for oral administration was 14.80, 10.80, and 13.07 hours, respectively, for the oral drench, crushed tablets in grain, and enrofloxacin solution in grain. Oral bioavailability for the oral drench, crushed tablets in grain, and enrofloxacin in grain was 4789, 98.07, and 94.60%, respectively, and median maximum concentration (Cmax) was 1.61, 2.69, and 2.26 microg/ml, respectively. Median Cmax of the multiple-dose regimen was 2.99 microg/ml. CONCLUSIONS AND CLINICAL RELEVANCE: Enrofloxacin administered orally to sheep has a prolonged half-life and high oral bioavailability. Oral administration at 10 mg/kg, q 24 h, was sufficient to achieve a plasma concentration of 8 to 10 times the minimum inhibitory concentration (MIC) of any microorganism with an MIC < or = 0.29 microg/ml.     

Neuroendocrine-immune interactions in fish: a role for interleukin-1

Bi-directional communication between the hypothalamus-pituitary-adrenal (HPA)-axis and the sympathetic nervous system with the immune system is crucial to ensure homeostasis. Shared use of ligands and especially receptors forms a key component of this bi-directional interaction. Glucocorticoids (GC), the major end products of the HPA-axis differentially modulate immune function. Cytokines, especially interleukin-1 (IL-1), tumour necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6), ensure immune signalling to the neuroendocrine system. In addition, hormones from leukocyte origin such as corticotropin-releasing hormone (CRH), adrenocorticotropic hormone (ACTH) and beta-endorphin, as well as centrally synthesised and secreted cytokines, contribute to the communication network.In teleost fish cortisol is the major product of the hypothalamus-pituitary-interrenal (HPI)-axis which is the teleost equivalent of the HPA-axis. Moderate and substantial increases in cortisol during stressful circumstances negatively affect B-lymphocytes, whereas rescue of neutrophilic granulocytes may support innate immunity. Recent elucidation of lower vertebrate cytokine sequences has facilitated research into neuroendocrine-immune interactions in teleosts and the first evidence for a significant function of interleukin-1 in the bi-directional communication is discussed.     

Efficacy of extended pirlimycin hydrochloride therapy for treatment of environmental Streptococcus spp and Staphylococcus aureus intramammary infections in lactating dairy cows

Fifty-one chronically infected lactating dairy cows were used to evaluate the efficacy of extended pirlimycin therapy regimens for treatment of intramammary infections by environmental Streptococcus spp and Staphylococcus aureus. Cows (n = 47) with one or more infected mammary quarters were blocked by parity and randomly allocated to one of three groups for treatment with pirlimycin (50 mg/mammary quarter) as follows: one treatment per day for 2 days (n = 36 infected mammary quarters); one treatment per day for 5 days (n = 36 infected mammary quarters); and one treatment per day for 8 days (n = 20 infected mammary quarters). Four cows with nine infected mammary quarters were included as untreated controls. Milk samples from each mammary quarter were collected 7 days before treatment, immediately before treatment, and weekly for 4 weeks after the final treatment for microbiological evaluation. A bacteriologic cure was defined as a treated, infected quarter that was bacteriologically negative for the presence of previously identified bacteria at weekly intervals after treatment. Efficacy of pirlimycin therapy against intramammary infections caused by environmental Streptococcus spp and S. aureus was 44.4%, 61.1%, and 95.0% for the 2-, 5-, and 8-day treatment regimens, respectively. None of the infections in the untreated control quarters was cured. Significant differences in efficacy were detected between all pirlimycin groups and the untreated control group, between the 8- and 2-day treatment regimens, and between the 8-day and 5-day treatment regimens (P < or = .05). Results of this study indicate that extended pirlimycin therapy was effective in eliminating intramammary infections caused by environmental streptococci and S. aureus in lactating dairy cows.     

Frequency of isolation and antimicrobial susceptibility patterns of Staphylococcus intermedius and Pseudomonas aeruginosa isolates from canine skin and ear samples over a 6-year period (1992-1997)

Staphylococcus intermedius (S. intermedius) was isolated from 88.6% and 49.4% of skin and ear samples, respectively, during the years 1992 through 1997, and frequency of isolation remained unchanged. More than 95% of all S. intermedius isolates were susceptible to cephalothin and oxacillin, providing support for empirical treatment of canine skin and ear infections with cephalexin. Pseudomonas aeruginosa (P. aeruginosa) was isolated from 7.5% and 27.8% of skin and ear samples, respectively. The frequency of isolation from skin samples increased over the study period. Because of multidrug-resistant profiles for P. aeruginosa isolates, especially for ear isolates, empirical treatment of P. aeruginosa infections is not advisable.     

Genetic Uniformity Among Isolates of Peronospora tabacina, the Tobacco Blue Mold Pathogen

ABSTRACT As a first step toward analysis of genetic variation and population structure in Peronospora tabacina, we used a collection of random genomic DNA fragments to survey for restriction fragment length polymorphisms (RFLPs) in DNA from a collection of isolates from Kentucky and other tobacco-growing regions of the United States. Also included in the study were isolates from the wild tobacco species, Nicotiana repanda, and from ornamental tobacco, N. alata. In a preliminary survey using DNA from 10 pathogen isolates, no polymorphisms were detected at six single-copy DNA loci using 22 probe-enzyme combinations. Moderately repetitive and highly repetitive regions of the genome were also remarkably similar between isolates, with only 6 of 15 different probes identifying genetic differences. Some of the polymorphic probes were then used to analyze a larger collection of isolates, most of which were from Kentucky. This resulted in the identification of very few additional polymorphisms, indicating that the population of P. tabacina that infects the Kentucky tobacco crop is genetically very homogeneous. The low level of polymorphism detected in this study overall, suggests that genetic variability may be lacking in P. tabacina populations throughout the United States. Two of the RFLP markers gave hybridization patterns that were consistent with P. tabacina being diploid. Frequencies of alleles at these loci and linkage disequilibrium between different marker loci indicated that genetic recombination does not occur frequently in the pathogen population. DNA polymorphisms that were identified in this study enabled us to differentiate the pathogen population into at least 10 haplotypes. One isolate was analyzed in detail and was shown to be genetically stable through several rounds of single-spore isolation and through several pathogenic cycles.     

Development of Contamination-Free Restriction Fragment Length Polymorphism Probes for the Obligate Biotroph Peronospora tabacina, an Oomycete Causing Blue Mold of Tobacco

ABSTRACT Peronospora tabacina is an obligately parasitic oomycete that causes blue mold, a devastating disease of tobacco. Genetic studies of this pathogen have been hampered by the lack of molecular markers. We generated a set of molecular markers for P. tabacina by collecting sporangiospores from infected tobacco leaves, extracting spore DNA, and cloning it in a plasmid vector. The resulting clones were then used to probe DNA from a collection of P. tabacina isolates to survey for polymorphisms. Most probes gave unexpected hybridization patterns with signal intensities that varied significantly from one DNA sample to another or between different DNA preparations of the same isolate. These results indicated that certain DNA preparations contained DNA from a source other than P. tabacina, which in turn suggested that some probes might have been derived from contaminating organisms present in the spore suspensions. Therefore, we characterized the inserts of several recombinant plasmids to determine their origins. Sequence analysis revealed that several of the inserts encoded peptides with similarity to bacterial proteins, suggesting that they were derived from bacterial contaminants. Of the remaining clones, five exhibited similarity to retroelements, one resembled eukaryotic helicase genes, and nine had no similarity to sequences in the databases. These were postulated to be true P. tabacina DNA clones. Verification of the origin of each probe was achieved by filtering a spore suspension, extracting DNA from the retentate and filtrate, and probing Southern blots of these DNA samples. These experiments confirmed the probe origins predicted by sequence analysis, resulting in the generation of 20 different restriction fragment length polymorphism probes that are specific for P. tabacina DNA. These probes should enable identification of reliable genetic markers for population studies of the blue mold organism.     

Consensus statement on ehrlichial disease of small animals from the infectious disease study group of the ACVIM. American College of Veterinary Internal Medicine

Within the past several decades, the number of Ehrlichia spp. recognized to infect cats, dogs, and human beings has expanded substantially. The recent application of advanced techniques in molecular biology has changed how ehrlichiosis is diagnosed and has provided new tools for the assessment of treatment. As these techniques are applied, the numerous questions that relate to the management of dogs and cats with ehrlichiosis ultimately will be answered. We hope this consensus statement will assist veterinarians in the management of their patients.