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Internal fixation of radial and ulnar fractures in three goats was accomplished using bone plates. Intervals between the time of fracture and internal fixation varied from one to 13 days. The goats were ambulatory the day after surgery, and recoveries were uneventful.  相似文献   
3.

Background

Grazed grassland management regimes can have various effects on soil fauna. For example, effects on earthworms can be negative through compaction induced by grazing animals, or positive mediated by increases in sward productivity and cattle dung pats providing a food source. Knowledge gaps exist in relation to the behaviour of different earthworm species i.e. their movement towards and aggregation under dung pats, the legacy effects of pats and the spatial area of recruitment. The present study addressed these knowledge gaps in field experiments, over 2 years, using natural and simulated dung pats on two permanent, intensively grazed pastures in Ireland.

Results

Dung pats strongly affected spatial earthworm distribution, with up to four times more earthworms aggregating beneath pats, than in the control locations away from pats. In these earthworm communities comprising 11 species, temporally different aggregation and dispersal patterns were observed, including absence of individual species from control locations, but no clear successional responses. Epigeic species in general, but also certain species of the anecic and endogeic groups were aggregating under dung. Sampling after complete dung pat disappearance (27 weeks after application) suggested an absence of a dung pat legacy effect on earthworm communities. Based on species distributions, the maximum size of the recruitment area from which earthworms moved to pats was estimated to be 3.8 m2 per dung pat. Since actual grazing over 6 weeks would result in the deposition of about 300 dung pats per ha, it is estimated that a surface area of 1140 m2 or about 11% of the total grazing area can be influenced by dung pats in a given grazing period.

Conclusions

This study showed that the presence of dung pats in pastures creates temporary hot spots in spatial earthworm species distribution, which changes over time. The findings highlight the importance of considering dung pats, temporally and spatially, when sampling earthworms in grazed pastures. Published comparisons of grazed and cut grasslands probably reached incorrect conclusions by ignoring or deliberately avoiding dung pats. Furthermore, the observed intense aggregation of earthworms beneath dung pats suggests that earthworm functions need to be assessed separately at these hot spots.
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Journal of Soils and Sediments - The successful implementation of a plant protection product depends on its effectiveness against a target species and its safety for the environment. Risk...  相似文献   
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Absorbed thyroid dose and effective half-life were determined in 46 hyperthyroid cats after treatment with a low dose (mean 111MBq) of radioiodine intravenously. Thirteen of these cats had received iohexol for glomerular filtration rate (GFR) measurement within 24h before treatment with radioiodine in view of another ongoing study at our institution. Pre-therapy values were obtained for total thyroxine (TT(4)) and for the thyroid to salivary gland ratio with sodium pertechnetate gamma-camera imaging. All cats underwent post-therapy scans at 24, 48 and 120 h for evaluation of radioactive iodine uptake (RAIU) and the effective half-life of radioiodine. The absorbed dose was calculated from the cumulative activity with Olinda software. Both groups were comparable in age, TT(4) and the ratio of thyroid activity to salivary gland activity. Statistical analysis revealed a significant decreased absorbed dose in the thyroid in the iohexol group. This decreased uptake was not accompanied by an decreased effective half-life of the radioiodine. The variation of inter-individual RAIU decreased in this group and more homogenous absorbed doses were obtained. No significant difference in outcome could be demonstrated. However, a tendency towards a higher number of residual hyperthyroidism in the iohexol group was noted (15 versus 6% in control group). This study demonstrates that iohexol interferes with the uptake of radioiodine in the hyperthyroid cat but does not provoke increased turnover. In this study, albeit including a small number of cats, outcome did not seem to be significantly affected.  相似文献   
7.
Assessing the potential environmental impact of alien plants and plant pests is notoriously difficult. New protocols have been developed in the framework of the EC project PRATIQUE to provide guidance on environmental impact assessment in the EPPO pest risk analysis (PRA) decision‐support scheme and enhance consistency between risk assessors and risk ratings for different pests. A set of questions with rating guidance and examples is provided, and individual scores are summarized into final scores, using a hierarchy of risk matrices, to assess current and potential environmental impacts. Two separate protocols are available: for alien plants and for other pests. These protocols could also be used to assess environmental impact in other PRA schemes as well as to assign alien species to regional black lists or to prioritize species for management decisions.  相似文献   
8.
Respiration of a soil used for vegetable crops at the beginning of the vegetation period Soil respiration was measured with a new portable soil respiration system (PP Systems, Hitchin, England) in vegetable plots in the greenhouse and field near Bonn from January to May 1996 with the following results:
  • 1 The equipment proved suitable for the purpose over a wide range of temperatures.
  • 2 Soil respiration ranged from less than 26 mg CO2 in winter, 30–180 mg CO2 in spring to 700 mg CO2 m?2 h?1 in summer with large variations.
  • 3 The largest soil respiration was recorded from peat-based commercial potting compost with small variations between measurements.
  • 4 The Q10 was 2,5 (±0,6) in the field for temperatures between 5–25°C.
  • 5 The rate of soil respiration was affected by soil cultivation with the effect declining with temperature: Ploughing, which unveiled cold and produced a coarse soil surface, reduced soil respiration, whereas soil respiration was increased by fine soil cultivation.
  • 6 In vegetable plots, soil respired 6–12 kg in cold (4°C), 40–50 kg CO2 in cool (14°C) conditions in April and 170–210 kg CO2/ha and 24 hours in warm (27°C) weather.
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9.
Fish farms have been shown to aggregate large numbers of wild fish in their surroundings. Although little is known about how this affects the local fishery, two hypotheses have been put forward; a trapping and a protecting effect on wild fish. This study provides the first monitoring of commercial and recreational fishing activity at a fish farm. We assessed the effect on the small‐scale fishery analysing the differences between fishing in farm proximity and away from the farm (in terms of catch rate, income and catch composition). Moreover, we estimated the biomass removal from fishing activities by farm employees inside the farm. The study was conducted from January 2011 to June 2012 at a Gilthead seabream farm in the NW Mediterranean. The findings revealed a relevant amount of commercial and recreational fishing effort in farm proximity. Yet, the results showed no benefit or difference of fishing in close proximity to the farm compared with areas away from the farm. Thus, we conclude that farm‐aggregated fish are protected from the commercial fleet by the farm leasehold area, but remain vulnerable to hidden fishing practices inside the farm, where farm employees harvest more than 4 t of wild fish annually.  相似文献   
10.
Factors influencing within‐farm variability of wild fish aggregations have not been systematically studied. We tested the hypothesis that fish abundance and species composition vary between feeding and non‐feeding periods and different bottom substrates within a Sparus aurata (L.) farm. Sampling took place during feeding and non‐feeding periods on six consecutive days in July 2011. Visual censuses were carried out at three different depths and at three sampling stations over rocky–sandy and sandy substrates respectively. In all, 33 species belonging to 17 families were observed. Total fish abundance, biomass and species community significantly differed between feeding and non‐feeding periods. Each depth was represented by a distinct species community and was therefore affected differently by the feeding activity. At the surface, fish abundance was significantly higher during feeding compared with non‐feeding periods. The distance from the feeding vessel significantly influenced fish aggregations in the water column, indicating that planktivorous species learnt to associate the boat noise with food availability through classic conditioning. At the bottom, substrate type was the dominant factor explaining aggregation variability. This study provides new information about the dynamics of fish aggregations within farms, emphasizing the importance of considering the different sources of variability in future study designs.  相似文献   
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