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In Europe, the classification systems of the WHO, WOAH (founded as OIE), and EMA are the prevailing standard documents guiding the prudent use of antibiotic substances. While the WHO document “Critically important antimicrobials for human medicine” eponymously focusses on the use in humans, the other two documents, “OIE List of Antimicrobial Agents of Veterinary Importance” and “EMA Categorization of antibiotics for use in animals,” concentrate exclusively on the prudent use of antibiotics in animals. One common purpose of these classification systems is to provide guidance in making sound decisions on the choice of antibiotics for treating humans as well as animals. Although the latest editions of these compendia refer to one another and bear a clear resemblance at the category levels, some of the substances are grouped into unequal classes. This review illustrates the specific perspectives of the three categorization systems under consideration. The arguments raised for different classifications between the WHO and the EMA are exemplified for amoxicillins without beta-lactamase inhibitors, macrolides, sulfonamides, and colistin. For the daily clinical use of antibiotics, veterinarians should consider the EMA document, and, under tentative circumstances, consult the OIE list.

Doxicycline is a structural isomer who meets the European reference standard (Ph.Eur. III 1997:0272) and respect EU Regulations for M.R.L. The good solubility permits high tissular absorption and distribution after administration in drinking water. The aim was to ascertain the clinical effects and tolerance consecutive to risen doses administration, as a part of safety study for this antibiotic in poultry in the respect of current drug testing methodology. The safety study revealed: good local and general tolerance to therapeutic doses (10 mg x kgb.w.-1) and to x2 dose, diarrhoea in lots which received x3 and x5 the therapeutic dose. Comparatively with the Control lot, haemoleucogram doesn’t suffer evident changes the registered values being between the references limits (exception of leucocitary formula). Also it was found an increased creatinin concentration consecutively to x3 and x5 greater doses administration and marked increasing of ASAT level and limited for ALAT’s, comparatively to control lot in the case of E4 lot, but light to reference values. Macro and microscopy revealed for the liver samples: hepatomegaly, diffuse hepatic degenerescence, nuclear heterochromatinization, vacuolar degenerescence; renal changes in nefrons and renal corpuscles, light splenomegaly, caecal sacs distension and brown-yellowish gaseous content to lots E3 and E4.

The aim of study is a therapeutic assessment of doxicycline’s hyclate efficacy, a wide spectrum antibiotic (efficient in majority of bacterial Gram-positive and Gram-negative infections and mycoplasmas, frequently isolated in poultry) in a colisepticemia outbreak in a 3,000 chicken farm. Disease started at the broiler’s age of 20 days and mortality rate reached 32.5%. The behaviour to antibiotics of isolated bacterial strains was tested and antibiogram (Sanofi) was used, doxicycline revealing a very good antibiotic activity. The treatments (with the dose of 10 mg x kg.b.w.-1) were done individually for five days, clinical evolution being observed until day ten of the experiment. Analyzing evolutions after treatments it was observed that the mortality diminished progressively from 14.2% in the first day, to 8.3% - 5.9% - 2.5% - 1.7% and respectively 0.8% in the sixth treatments day, in days seven, eight, nine, and ten of the study not being registered any mortality cases. In our opinion the favorable clinical evolution was recorded after the third treatment day, at the end of experiment from 120 remaining live 80 chickens (representing 66.7%) proving the fact that doxicycline was efficient, confirmed also by the average daily weight gain for the remaining live chickens.

Abstract The biological impact of low dose magnetic fields generated by electric appliances present in the human environment is still uncertain. In this study, human placentas served as a model tissue for the evaluation of the potential effect of oscillating low intensity magnetic fields on the concentration of 8-hydroxy-2'-deoxyguanosine (8-OH-dG) in cellular DNA. Cotyledons were dissected from placentas obtained immediately after physiological labours and exposed to magnetic fields (groups MF A, 2 mT, 50 Hz and MF B, 5 mT, 50 Hz) or sham exposed (group C) during an in vitro perfusion of 3 h. Cellular DNA was isolated, hydrolyzed and analyzed by HPLC. Native nucleosides were monitored at 254 nm and 8-OH-dG by electrochemical detection. Results were expressed as µmol 8-OH-dG/mol deoxyguanosine (dG). The concentrations of 8-OH-dG in group C, MF A and MF B were 28.45±15.27 µmol/mol dG, 62.80±31.91 µmol/mol dG, and 27.49±14.23 µmol/mol dG, respectively, demonstrating no significant difference between the groups. The results suggest that placental tissues possess a capacity to protect DNA against oxidative alterations by magnetic field of intensities previously shown to produce radical mediated DNA damage in rat brain cells in vivo and imbalances in electrolyte release of cotyledons under in vitro conditions. [ABSTRACT FROM AUTHOR]