Effect of mineral nitrogen fertilizer forms on N2O emissions from arable soils in winter wheat production

Nitrogen fertilizers are supposed to be a major source of nitrous oxide (N₂O) emissions from arable soils. The objective of this study was to compare the effect of N forms on N₂O emissions from arable fields cropped with winter wheat (Triticum aestivum L.). In three field trials in North‐West Germany (two trials in 2011/2012, one trial in 2012/2013), direct N₂O emissions during a one‐year measurement period, starting after application of either urea, ammonium sulfate (AS) or calcium ammonium nitrate (CAN), were compared at an application rate of 220 kg N ha^?1. During the growth season (March to August) of winter wheat, N₂O emission rates were significantly higher in all three field experiments and in all treatments receiving N fertilizer than from the non‐fertilized treatments (control). At two of the three sites, cumulative N₂O emissions from N fertilizer decreased in the order of urea > AS > CAN, with emissions ranging from 522–617 g N ha^?1 (0.24–0.28% of applied fertilizer) for urea, 368–554 g N ha^?1 (0.17–0.25%) for AS, and 242–264 g N ha^?1 (0.11–0.12%) for CAN during March to August. These results suggest that mineral nitrogen forms can differ in N₂O emissions during the growth period of winter wheat. Strong variations in the seasonal dynamics of N₂O emissions between sites were observed which could partly be related to weather events (e.g., precipitation). Between harvest and the following spring (post‐harvest period) no significant differences in N₂O emissions between fertilized and non‐fertilized treatments were detected on two of three fields. Only on one site post‐harvest emissions from the AS treatment were significantly higher than all other fertilizer forms as well as compared to the control treatment. The cumulative one‐year emissions varied depending on fertilizer form across the three field sites from 0.05% to 0.51% with one exception at one field site (AS: 0.94%). The calculated overall fertilizer induced emission averaged for the three fields was 0.38% which was only about 1/3 of the IPCC default value of 1.0%.     

Methicillin-resistant Staphylococcus pseudintermedius among dogs admitted to a small animal hospital

The aim of this study was to determine the frequency of carriage of methicillin-resistant Staphylococcus pseudintermedius (MRSP) among dogs admitted to a small animal hospital during a 17-month period, to characterize these isolates and to initially screen for possible factors associated with MRSP carriage. Swabs were taken from the nose/pharynx and the perineum as well as from wounds and skin infections (if present) of 814 dogs before entering the small animal hospital. A questionnaire for background information was completed. The staphylococcal species and methicillin resistance were confirmed pheno- and genotypically. The identified MRSP isolates were characterized by SCCmec typing, testing for susceptibility to 25 antimicrobial agents and SmaI-directed pulsed-field gel electrophoresis. A first screening for possible risk factors for MRSP carriage was performed by means of unifactorial contingency tables and CART analysis. Sixty (7.4%) dogs were positive for MRSP. All MRSP isolates harboured a type II-III SCCmec cassette and showed extended resistance to antimicrobial agents. Fifteen different SmaI patterns were observed. The major factors that clustered with MRSP carriage were former hospitalization and antibiotic treatment within the last six months before sampling. This study showed that only a minor part of the sampled dogs carried multi-resistant MRSP isolates. The facts that prior hospitalization and/or antibiotic therapy are potential associated factors for MRSP carriage underline the necessity of a judicious use of antibiotics in small animal medicine.     

Polycyclic Aromatic Hydrocarbons in Soils from European High Mountain Areas

Polycyclic aromatic hydrocarbons (PAHs) were analyzed in 70 soils distributed in mountain areas such as Montseny (300?C1,700 m), Pyrenees (1,500?C2,900 m), Alps (1,100?C2,500 m), and Tatras (1,400?C1,960 m). Average total PAH concentrations, excluding retene and perylene, were about 400 ng/g in the Pyrenees and 1,300?C1,600 ng/g in the other mountain ranges. No correlations between PAH concentrations and total organic carbon were observed. Retene was the major PAH in the Pyrenean soils of lower altitude. No altitudinal dependence was found between soil PAH concentrations and elevation for the whole dataset. However, in the Tatra soils a statistically significant correlation with altitude was observed involving higher concentrations at higher altitude. This correlation was due to the statistically significant altitudinal dependence of the more volatile PAHs. Another observed altitudinal trend concerned the benz[a]anthracene/(benz[a]anthracene + chrysene + triphenylene) and the benzo[a]pyrene/(benzo[a]pyrene + benzo[e]pyrene) ratios that exhibited a decrease in the more chemically labile compounds, benz[a]anthracene and benzo[a]pyrene, respectively, in the soils located at higher altitude. This observation is consistent with the expected higher photooxidation at higher mountain altitude.     

Monitoring changes in distribution of pulmonary ventilation by functional electrical impedance tomography in anaesthetized ponies

Objective

To assess changes in the distribution in pulmonary ventilation in anaesthetized ponies using electrical impedance tomography (EIT).

Magnetic resonance imaging of feline hippocampal necrosis

The clinical, neuropathologic, and magnetic resonance (MR) imaging features in four cats with necrosis of the hippocampus and piriform lobe are described. All cats had acute generalized seizures and behavioral changes including aggression, salivation, polyphagia, and disorientation. Routine hematologic, serum chemistry, and cerebrospinal fluid analyses were normal. MR imaging abnormalities were restricted to the area of the hippocampus and piriform lobe. The lesions were T2-hyperintense, T1-hypointense, and were characterized by various degrees of contrast enhancement. Lesions were consistent with necrotizing encephalitis. Two cats were euthanized and underwent postmortem examination within a week after MR imaging due to the lack of response to antiepileptic drug therapy and progressive neuropathy. The remaining two cats lived for about four months and were then euthanized because of persistent behavioral and neurologic signs; only one of these cats underwent postmortem examination with histopathologic examination. Histopathological findings were typical of severe, diffuse, bilateral symmetric necrosis, and degeneration of neurons in the hippocampus and piriform lobe, but an etiologic agent was not apparent. This apparently unique feline syndrome, now reported in Switzerland and Italy, has no known cause at this time.