Successful transcatheter retrieval of embolized Amplatz Canine Duct Occluders in two dogs

Transcatheter occlusion of patent ductus arteriosus (PDA) using an Amplatz® Canine Duct Occluder (ACDO) is routinely performed in dogs. Pulmonary embolization of the device is a rarely reported complication of this procedure. We report here the first two cases of successful transcatheter retrieval of an embolized ACDO. An 8-month-old, 21-kg, German shepherd (case 1) was referred for pulmonary edema secondary to a large PDA with left-to-right shunting. After medical stabilization, an emergency procedure for PDA closure was recommended. An 8-mm ACDO was deployed under general anesthesia. The device was released after confirming its stability with a gentle tug test but migrated into the pulmonary trunk. A 10-mm ACDO was subsequently successfully deployed and released. Vascular access was then obtained from the right jugular vein so that a vascular snare could be used to capture the ACDO waist and pull it back toward the right ventricle and then the right atrium. It was then removed through the jugular vein. The dog recovered uneventfully and was discharged after confirmation of complete ductal occlusion. The same complication occurred in a second case (case 2, asymptomatic 6-month-old, 7.9-kg, cocker spaniel), and a similar procedure was used to successfully retrieve the embolized device. Both dogs are still doing well 9 and 21 months, respectively, after the procedure. These cases illustrate that transcatheter retrieval of ACDO devices embolized in the pulmonary artery using vascular snares is technically feasible in the dog.     

Antimicrobial susceptibility and distribution of antimicrobial-resistance genes among Enterococcus and coagulase-negative Staphylococcus isolates recovered from poultry litter

Data on the prevalence of antimicrobial resistant enterococci and staphylococci from the poultry production environment are sparse in the United States. This information is needed for science-based risk assessments of antimicrobial use in animal husbandry and potential public-health consequences. In this study, we assessed the susceptibility of staphylococci and enterococci isolated from poultry litter, recovered from 24 farms across Georgia, to several antimicrobials of veterinary and human health importance. Among the 90 Enterococcus isolates recovered, E. hirae (46%) was the most frequently encountered species, followed by E. faecium (27%), E. gallinarum (12%), and E. faecalis (10%). Antimicrobial resistance was most often observed to tetracycline (96%), followed by clindamycin (90%), quinupristin-dalfopristin (62%), penicillin (53%), erythromycin (50%), nitrofurantoin (49%), and clarithromycin (48%). Among the 110 staphylococci isolates recovered, only coagulase-negative staphylococci (CNS) were identified with the predominant Staphylococcus species being S. sciuri (38%), S. lentus (21%), S. xylosus (14%) and S. simulans (12%). Resistance was less-frequently observed among the Staphylococcus isolates for the majority of antimicrobials tested, as compared with Enterococcus isolates, and was primarily limited to clarithromycin (71%), erythromycin (71%), clindamycin (48%), and tetracycline (38%). Multidrug resistance (MDR) phenotypes were prevalent in both Enterococcus and Staphylococcus; however, Enterococcus exhibited a statistically significant difference in the median number of antimicrobials to which resistance was observed (median = 5.0) compared with Staphylococcus species (median = 3.0). Because resistance to several of these antimicrobials in gram-positive bacteria may be attributed to the shuttling of common drug-resistance genes, we also determined which common antimicrobial-resistance genes were present in both enterococci and staphylococci. The antimicrobial resistance genes vat(D) and erm(B) were present in enterococci, vgaB in staphylococci, and mobile genetic elements Tn916 and pheromone-inducible plasmids were only identified in enterococci. These data suggest that the disparity in antimicrobial-resistance phenotypes and genotypes between enterococci and staphylococci isolated from the same environment is, in part, because of barriers preventing exchange of mobile DNA elements.     

Relationships between elm spanworm, Ennomos subsignaria, juvenile density and defoliation on mature sycamore maple in an urban environment

Using field surveys, we established sampling procedures for estimating defoliation resulting from elm spanworm, Ennomos subsignaria (Hübner) (Lepidoptera: Geometridae), feeding on mature sycamore maple, Acer pseudoplatanus L. (Aceraceae), in St. John's, Newfoundland and Labrador. We also determined whether densities of E. subsignaria eggs, egg masses, early- or late-instar larvae could predict the amount of defoliation at the end of the larval feeding period. Defoliation estimates acquired by sampling branches from only the lower, mid or upper crown explained ≥80% of the variation in tree-level defoliation, suggesting that density–defoliation relationships established using defoliation data from any crown level would also be useful for predicting tree-level defoliation. In linear regressions, egg and egg mass densities explained ≤20% of variation in defoliation and thus only provide a crude relative estimate of the amount of defoliation that will occur. Early- and late-instar larval density in the lower crown explained 53 and 29%, respectively, of the variation in defoliation in the lower crown, where defoliation levels were highest. Thus monitoring early-instar density in the lower crown should provide pest managers with reliable information for decisions regarding whether to apply suppression tactics while allowing enough time to implement these tactics, if necessary.     

Land tenure in the U.S.: power,gender, and consequences for conservation decision making

Land tenure relations have both social and environmental implications, ranging from potential power issues to land stewardship. Drawing upon survey data of landowners collected in the Great Lakes Basin of the U.S., this study builds upon existing research by examining absentee landlords of agricultural land—a vastly understudied but growing category of landowners. By furthering analysis on gender dynamics in the landlord-tenant relationship, the study findings augment Gilbert and Beckley’s (Rural Sociology, 1993) suggestion that subordinate landlord-dominant tenant relationships may be a pattern and contribute to understanding the nuances that co-ownership potentially plays in these relationships.     

Training evidence-based veterinary medicine by collaborative development of critically appraised topics

In current veterinary education, skills such as retrieving, critically appraising, interpreting, and applying the results of published scientific studies are rarely taught. In this study, the authors tested the concept of team-based development of critically appraised topics (CATs) in training students in evidence-based veterinary medicine (EBVM). The 116 participants were in their fifth year and attending the clinical rotation at the Clinic for Animal Reproduction. Students developed 18 CATs of varying quality on topics of their choice. Preparing the CATs in teams stimulated discussion on the topic and the quality of the retrieved papers. Evaluation of the project revealed that more than 90% of the students endorsed training in critical appraisal of information in veterinary education. In addition, more than 90% considered the development of CATs an effective exercise for assessing the quality of scientific literature. A provided literature evaluation form was perceived as a useful tool for systematically summarizing a publication's quality. In conclusion, team-based development of CATs during clinical rotations is highly valuable for training in EBVM. Learning and intrinsic motivation seem to be enhanced by creating a situation similar to veterinary practice because the task is embedded into an authentic clinical problem. This approach to clinical training helps to prepare students to integrate evidence from literature into practice.     

Prevalence, serovars, phage types, and antibiotic susceptibilities of Salmonella strains isolated from animals in the United Arab Emirates from 1996 to 2009

The aim of this study was to give some insights into the prevalence, serovars, phage types, and antibiotic resistances of Salmonella from animal origin in the United Arab Emirates. Data on diagnostic samples from animals (n?=?20,871) examined for Salmonella between 1996 and 2009 were extracted from the databases of the Central Veterinary Research Laboratory in Dubai and from typed strains (n?=?1052) from the Robert Koch Institute, Wernigerode Branch in Germany and analyzed for general and animal-specific trends. Salmonella was isolated from 1,928 (9 %) of the 20,871 samples examined. Among the 1,052 typed strains, most were from camels (n?=?232), falcons (n?=?166), bustards (n?=?101), antelopes (n?=?66), and horses (n?=?63). The predominant serovars were Salmonella Typhimurium (25 %), Salmonella Kentucky (8 %), followed by Salmonella Frintrop (7 %), and Salmonella Hindmarsh (5 %). When analyzed by animal species, the most frequent serovars in camels were Salmonella Frintrop (28 %) and Salmonella Hindmarsh (21 %), in falcons Salmonella Typhimurium (32 %), in bustards Salmonella Kentucky (19 %), in antelopes Salmonella Typhimurium (9 %), and in horses Salmonella Typhimurium (17 %) and S. Kentucky (16 %). Resistance of all typed Salmonella strains (n?=?1052) was most often seen to tetracycline (23 %), streptomycin (22 %), nalidixic acid (18 %), and ampicillin (15 %). These data show trends in the epidemiology of Salmonella in different animal species which can be used as a base for future prevention, control, and therapy strategies.     

Variation of seed mass and its effects on germination in <Emphasis Type="Italic">Polylepis australis</Emphasis>: implications for seed collection

South American Polylepis mountain forests are recognised as being one of the most endangered forest ecosystems in the world. Reforestation measures have been strongly recommended but may be hampered due to the very low seed germination reported for several Polylepis species. In order to facilitate reforestation we analysed the influence of seed mass on germination probability for Polylepis australis seeds in the Córdoba mountains (central Argentina). We collected seeds from 43 trees distributed throughout five woodland fragments located within two regions differing in size, topographical position, and altitude (1,900 m a.s.l. and 2,200 m a.s.l.). Seeds of Polylepis australis exhibited a great variation in terms of mass and percent seed germination among individual trees and among geographical regions. The results of logistic regression showed that germination probability was highly correlated with seed mass. However, the explained deviance significantly increased by including the region, the woodland fragment and especially the individual tree in addition to seed mass in the regression models. We conclude that selecting seeds on the basis of mass is an appropriate way to enhance germination prospects for reforestation projects. However, no absolute mass values are applicable in this context as the highest germination probabilities were reached at varying seed mass values depending on geographical region, woodland fragment or individual tree. We suggest collecting the relatively heaviest available seeds, even though the absolute seed mass may be low.     

Salmonella in poultry flocks and humans--S. enterica subspecies enterica serovar Enteritidis in the past

After importing of breeder lines for laying flocks from Canada into the former GDR in 1966 the egg industry in this country was completely isolated from that in Western Germany or other Western European countries until opening the border in Germany in 1989. Because of this isolation from other countries, an analysis of the clonal diversity of Salmonella (S.) Enteritidis isolates originated from humans, chickens and food in the former GDR during the 1980s would provide a unique opportunity to obtain new insight into factors that may have triggered the S. Enteritidis epidemic. While isolates had previously been typed by the phage typing scheme of Lalko and Laszlo we applied for the first time the extended phage typing scheme by Ward for the retrospective analysis of the S. Enteritidis strains. Furthermore, isolates of phage type (PT) 4/6 (Ward / Lalko and Laszlo) from different livestocks were investigated by ribotyping. Although in total the PT4/6 dominated between 1986 and 1989 in poultry, other phage types have prevailed in the early 1980s and represented a considerable fraction of isolates until 1989. For instance, PT8/7 was isolated from one large layer farm (district Halle) from 1988 until 1989. During that time in another farm (district Cottbus) only PT8/7 was detected too. PT4/6 was isolated from neither of these two laying hen farms. The strains of PT4/6 could be distinguished by ribotyping in 19 different subtypes. The strains from the northern farms were distinct from those isolated in the southern regions. As farms which were harbouring either PT4/6 or PT8/7 had obtained laying hens from the same sources (breeder lines in Deersheim and Spreenhagen) it is highly probable that S. Enteritidis infection was acquired from the environment at each individual farm. This conclusion is also supported by the presence of different PT4/6 ribotypes in different farms. The presence of different phage types or PT4/6 ribotypes at different farms of laying hens suggests that in each case the S. Enteritidis strains present in the environment were able to enter chicken flocks.     

Drying kinetics of calcium caseinate

Drying is a major component of the cost of making caseinate-based films. We determined the drying curves for making calcium caseinate/glycerol films at low and high relative humidity at 21-34 degrees C. The drying curves exhibited a very long constant rate period followed by a single falling rate period. Much of the drying was in the constant rate period and preceded the actual film formation. Normally, calcium caseinate solutions are dried from about 5% solids, but it was possible to start with a more concentrated solution, 10% solids, to avoid much of the constant rate period. The resulting films were equal to those prepared starting at high initial moisture. An estimate of the drying costs indicated it is much cheaper to start with the more concentrated solutions.