Development of a monitoring program for antibiotic resistance in bacteria from Swiss food-producing animals

Resistant bacteria from food-producing animals may compromise the success of antibiotic treatment in animals and in humans. Therefore, the level of antibiotic resistance in bacteria from farm animals and its development over time needs to be monitored. In Switzerland, a monitoring program for antibiotic resistance is currently being developed. Pilot-monitoring programs were conducted in selected animal species in order to obtain current data on antibiotic resistance. The data on the prevalence of bacteria and antibiotic resistance in poultry were used to optimize the sampling plan. The influence of sampling more farms compared to sampling more animals per farm on the prevalence estimate for antibiotic resistance was analyzed by a Monte Carlo simulation model. Accounting for the costs for sample collection, transportation and laboratory analysis of the samples, the number of samples to be taken at the respective step in the production line was optimized. Optimization was defined as maximizing the precision of the prevalence estimate while minimizing the costs. The model will be expanded to other bacterial and animal species in the future.     

Forstliche Ertragsregelung in der Oberlausitz im Spiegel der Geschichte

In einer Reihe älterer und neuerer Veröffentlichungen habe ich die forstlichen Verhältnisse in der Oberlausitz in ihrer geschichtlichen Entwicklung und der Struktur, die sie zu Beginn des letzten Weltkrieges hatte, untersucht. Wenn ich in der vorliegenden Arbeit die geschichtliche Entwicklung der Ertragsregelung einer Betrachtung unterziehe, so bitte ich den speziell interessierten Leser, die bisher erschienenen Abhandlungen und Kapitel zu berücksichtigen:

1. 1.
   Jagdliches aus der Oberlausitz. — Thar. Forstl. Jahrb. 89, 1938, S. 758–769.     

Comparative assessment of bone mineral measurements obtained by use of dual-energy x-ray absorptiometry, peripheral quantitative computed tomography, and chemical-physical analyses in femurs of juvenile and adult dogs

OBJECTIVE: To compare bone mineral measurements obtained by use of dual-energy x-ray absorptiometry (DEXA), peripheral quantitative computed tomography (pQCT), and chemical-physical analyses and determine effects of age and femur size on values obtained for the various techniques. SAMPLE POPULATION: Femurs obtained from 15 juvenile and 15 adult large-breed dogs. PROCEDURE: n each femur, 7 regions of interest were examined by use of DEXA to measure the bone mineral content (BMC) and bone mineral density (BMD), and 5 were examined by use of pQCT to measure BMD. Among these, 1 region was examined by both noninvasive methods and an invasive method. Volume of the femur was determined by water displacement. Volumetric bone density (VBD) was calculated. Calcium (Ca), phosphorus (P), total Ca, and total P contents were determined. RESULTS: DEXA- and pQCT-derived results revealed that all values increased with age in juvenile dogs. In adults, VBD and pQCT-derived BMD decreased significantly and DEXA-derived BMD increased with increasing femur length.The pQCT-derived BMD correlated well with VBD and Ca content, whereas DEXA-derived BMC was strongly correlated with Ca content. In juveniles, values correlated regardless of the technique used, whereas in adult dogs, DEXA-derived BMD did not correlate with pQCT-derived BMD, Ca concentration, or VBD unless data were adjusted on the basis of femur length. CONCLUSIONS AND CLINICAL RELEVANCE: DEXA-derived BMD adjusted for femur length yields approximately the same percentage variability in VBD as for pQCT-derived BMD. However, pQCT-derived BMD is still more sensitive for determining variability BMD in Ca concentration, compared with DEXA-derived BMD adjusted for femur length.     

A comparison of florfenicol and tulathromycine for the treatment of undifferentiated fever in feedlot calves

The purpose of this study was to compare the relative cost-effectiveness of florfenicol with that of tulathromycin for treatment of undifferentiated fever (UF) in feedlot calves at ultra-high risk of developing UF that receive metaphylactic tulathromycin on arrival at the feedlot. Calves that received therapeutic florfenicol had lower overall mortality (P=.045) and bovine respiratory disease mortality (P=.050) compared with calves that received therapeutic tulathromycin, but no significant differences were detected in feedlot performance, carcass characteristics, or other animal health variables. There was a net advantage of Can$41.19/treated animal in the florfenicol group versus the tulathromycin group. This study demonstrates that it is more cost-effective to use florfenicol than tulathromycin for the initial treatment of UF in feedlot calves at ultra-high risk of developing UF that receive on-arrival metaphylactic tulathromycin.     

Lingual abscesses in three dogs

Lingual abscessation is a rare condition in dogs. Very little information is available on the diagnosis and treatment of lingual abscesses in the major surgical textbooks and current veterinary literature. The common clinical signs of lingual abscesses are macroglossia, hypersalivation and a reluctance to open the mouth, but these can vary depending on the time course of the disease and the location of the abscess. This article presents three cases of tongue abscess in the dog outlining treatment and outcomes. A thorough diagnostic work up, consisting of anamnesis, clinical and haematological examinations, oral inspection under sedation and the use of diagnostic imaging techniques should be mandatory before surgical exploration of the abscess. Surgery is followed by drainage and systemic antibiotics, complemented by systemic fluid support and pain management. Conservative management of lingual abscesses can be fatal. Sharp trauma from an unknown object is suspected to be the underlying cause for the abscesses in the present cases.     

The use of age-clustered pooled faecal samples for monitoring worm control in horses

A study was performed on two horse farms to evaluate the use of age-clustered pooled faecal samples for monitoring worm control in horses. In total 109 horses, 57 on farm A and 52 on farm B, were monitored at weekly intervals between 6 and 14 weeks after ivermectin treatment. This was performed through pooled faecal samples of pools of up to 10 horses of the groups 'yearlings' (both farms), '2-year-old' (two pools in farm A), '3-year-old' (farm A) and adult horses (four pools on farm A and five pools on farm B), which were compared with the mean individual faecal egg counts of the same pools. A very high correlation between the faecal egg counts in pooled samples and the mean faecal egg counts was seen and also between the faecal egg counts in pooled samples and larval counts from pooled faecal larval cultures. Faecal egg counts increased more rapidly in yearlings and 2-year-old horses than in older horses. This implied that in these groups of young animals faecal egg counts of more than 200 EPG were reached at or just after the egg reappearance period (ERP) of 8 weeks that is usually indicated for ivermectin. This probably means that, certainly under intensive conditions, repeated treatment at this ERP is warranted in these young animals, with or without monitoring through faecal examination. A different situation is seen in adult animals. Based on the mean faecal egg counts on both farms and on the results of pooled samples in farm A, using 100 EPG as threshold, no justification for treatment was seen throughout the experimental period. However, on farm B values of 100 EPG were seen at 9 and 11, 13 and 14 and 14 weeks after ivermectin treatment in pools 10, 12 and 13, respectively. This coincided with the presence of one or two horses with egg counts above 200 EPG. The conclusion is that random pooled faecal samples of 10 adult horses from a larger herd, starting at the ERP and repeating it at, for instance, 4-week intervals, could be used for decisions on worm control. However, there would be a certain risk for underestimating pasture contamination through missing high-egg excreters. An alternative use of pooled samples would be as a cheap first screening to detect which adult horses really contribute to pasture contamination with worm eggs on a farm. All horses should be sampled and subsequently animals from 'positive' pools can be reexamined individually.     

Development and evaluation of a recombinant antigen-based ELISA for serodiagnosis of cattle lungworm

An optimised enzyme-linked immunosorbent assay (ELISA) for the detection of Dictyocaulus viviparous-specific antibodies was developed and evaluated following the testing of various microtitration plates and anti-bovine Ig-conjugates. Based on recombinant major sperm protein (MSP) expressed as a glutathione-S-transferase (GST) fusion protein in Escherichia coli, sera collected from 112 cattle experimentally infected with D. viviparus, from 129 helminth-na?ve calves, 8 calves experimentally infected with Ostertagia ostertagi, and 2 calves infected with Cooperia oncophora were tested. ELISA results showed a calculated specificity and sensitivity as well as positive and negative predictive values of >99%. No cross-reactions with sera from calves infected with O. ostertagi or C. oncophora were observed. Lungworm-specific immunoglobulins were first detected from 28 to 35 days post-infection onwards. To differentiate between antibody-binding to the MSP-part or the GST-part of the fusion protein, additional ELISAs were performed using pure recombinant MSP or GST. Optical densities obtained from the ELISAs with the MSP showed a similar pattern to optical densities measured in the ELISAs with the fusion protein, whereas GST gave only a low background. By testing serum samples from naturally infected calves, it was found that the MSP-ELISA is positive even for sera from calves showing very low faecal larval counts. Thus, we conclude that the ELISA using the recombinant MSP-fusion protein appears to be a suitable method for routine diagnosis and epidemiological studies of cattle lungworm.     

Acaricidal activity of limonene, limonene oxide and beta-amino alcohol derivatives on Rhipicephalus (Boophilus) microplus

Limonene, limonene oxide and eight beta-amino alcohol derivatives obtained by synthesis were investigated for the effect on egg hatchability and mortality rates of newly hatched larvae of the cattle tick Rhipicephalus (Boophilus) microplus. At the doses between 10mug/ml and 2.5mug/ml all the compounds were highly lethal to the larvae and some of them showed activity at lower concentrations. The effect on the eggs hatchability was observed in all the treatments.     

A mycolyl transferase mutant of Rhodococcus equi lacking capsule integrity is fully virulent

Rhodococcus equi is a mucoid Gram-positive facultative intracellular pathogen which can cause severe bronchopneumonia in foals and AIDS patients. A polysaccharide capsule which gives R. equi a mucoid appearance has long been suspected to be a virulence factor. Here, we describe a transposome mutant in the gene fbpA of strain R. equi 103 causing absence of a capsular structure. FbpA is a chromosomal gene homologous to antigen 85 (Ag85) mycolyl chain transferase gene of Mycobacterium tuberculosis. The mutant multiplied normally in isolated macrophages, was able to establish the unusual R. equi-containing vacuole in macrophages, was cytotoxic for macrophages, and was virulent in a mouse model. Colonies had a dry appearance on nutrient agar and defective capsule structure. Surprisingly, fbpA mutants cured of the virulence-associated plasmid were found in a phagosome that was more alkaline than that of the corresponding wild-type bacteria, were more cytotoxic and even multiplied to some extent. This study suggests that the capsule is not an important virulence factor of R. equi and that it may even counteract virulence traits.