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101.
102.
The overall trend and the trend within birth cohorts of the prevalence of bovine spongiform encephalopathy (BSE) in cattle found dead, euthanased or emergency slaughtered on farms in the Bretagne, Basse Normandie and Pays de la Loire regions of France, during the periods from August 7 to December 22 in 2000, 2001 and 2002, were analysed by non-conditional logistic regression, adjusted for the region and for the type of animals. The overall prevalence of BSE during these three periods decreased from 2.71 per 1000 in 2000 to 1.41 per 1000 in 2001 and 0.42 per 1000 in 2002. The prevalence within birth cohorts started to decrease for the cohort born between July 1, 1995 and June 30, 1996 (cohort 95/96) and the trend was reinforced for cohort 96/97, suggesting that the exposure of animals to the BSE agent had started to decrease for animals born after July 1995, that is, one year before the ban on specified risk materials in meat and bone meal was implemented in France. However, considering that most of the animals would have been infected at between six and 18 months of age, the decrease may have been due, at least partly, to this control measure.  相似文献   
103.
Two-dimensional electrophoresis was used to investigate sarcoplasmic protein expression in pig Semimembranosus muscles sampled 20 min after slaughter. Two groups (light and dark) of 12 animals were selected from 1000 pigs, based on meat L values measured 36 h postmortem. Twenty-two proteins or fragments (p < 0.05) were differentially expressed. Muscles leading to darker meat had a more oxidative metabolism, indicated by more abundant mitochondrial enzymes of the respiratory chain, hemoglobin, and chaperone or regulator proteins (HSP27, alphaB-crystallin, and glucose-regulated protein 58 kDa). Conversely, enzymes of glycolysis were overexpressed in the lighter group. Such samples were also characterized by higher levels of glutathione S-transferase omega, which can activate the RyR calcium channels, and higher levels of cyclophilin D. This protein pattern is likely to have severe implications on postmortem metabolism, namely, acceleration of ATP depletion and pH fall and subsequent enhanced protein denaturation, well-known to induce discoloration.  相似文献   
104.
This article describes educational approaches for training veterinary students, veterinary graduates, and practicing veterinarians in the area of aquatic animal health and lists a range of general research, training, internship/residency, and continuing-education resources.  相似文献   
105.
EPPO member countries requested that a study be conducted to identify and better address the risks presented by the trade of plants for planting, which has led to numerous introductions of pests into the EPPO region in recent years. Concerns were raised about the efficacy of the current plant health systems in place in the EPPO region to deal with the risks presented by plants for planting. The EPPO Study on the Risk of Imports of Plants for Planting was launched by the EPPO Council in 2010. The first part of the Study was completed in spring 2012. It was published as EPPO Technical Document 1061 ( http://www.eppo.int/QUARANTINE/EPPO_Study_on_Plants_for_planting.pdf ). Examples of pest outbreaks in the EPPO region suspected to be caused by international trade of plants for planting were analyzed. This analysis identified characteristics of the pest/crop/trade patterns associated with the risks of importing pests. These characteristics are described as criteria that are intended to be used in a screening process to enable identification of commodities that require an assessment prior to import in the EPPO region. The further elaboration of the screening process is briefly outlined.  相似文献   
106.
The efficacy of Oridermyl® (acaricidal/antibiotic/antifungal/anti-inflammatory ointment) and Revolution® (selamectin spot-on) was compared in a blinded randomized study on 24 adult cats with otoacariasis. Twelve cats were treated once daily for 10 d with Oridermyl® and 12 cats were treated on Day 0 with Revolution®. Otitis was assessed with cytological counts of mean number of bacteria and yeast on Days 0 and 10, and scored clinically every other day. All auricular secretions were removed for mite count on Day 10. On Day 0, cytological examination confirmed the presence of secondary bacterial (24/24) and fungal (21/24) infections. No live mites were observed otoscopically after Day 4 and in auricular secretions at Day 10 in both groups. On Day 10, secondary infections were resolved for all cats treated with Oridermyl® but were present in all cats treated with Revolution®. Improvement in clinical signs of otitis over time was superior in the Oridermyl® group (P < 0.001).  相似文献   
107.
108.
Natural temperature gradient (NTG) can be a significant problem in thermal sap flow measurements, particularly in dry environments with sparse vegetation. To resolve this problem, we propose a novel correction method called cyclic heat dissipation (CHD) in its thermal dissipation probe (TDP) application. The CHD method is based on cyclic, switching ON/OFF power schema measurements and a three-exponential model, extrapolating measured signal to steady state thermal equilibrium. The extrapolated signal OFF represents NTG, whereas the extrapolated signal ON represents standard TDP signal, biased by NTG. Therefore, subtraction of the OFF signal from the ON signal allows defining the unbiased TDP signal, finally processed according to standard Granier calibration. The in vivo Kalahari measurements were carried out in three steps on four different tree species, first as NTG, then as standard TDP and finally in CHD mode, each step for ~1-2 days. Afterwards, each tree was separated from its stem following modified Roberts' (1977) procedure, and CHD verification was applied. The typical NTG varying from ~0.5 °C during night-time to -1 °C during day-time, after CHD correction, resulted in significant reduction of sap flux densities (J(p)) as compared with the standard TDP, particularly distinct for low J(p). The verification of the CHD method indicated ~20% agreement with the reference method, largely dependent on the sapwood area estimate. The proposed CHD method offers the following advantages: (i) in contrast to any other NTG correction method, it removes NTG bias from the measured signal by using in situ, extrapolated to thermal equilibrium signal; (ii) it does not need any specific calibration making use of the standard Granier calibration; (iii) it provides a physical background to the proposed NTG correction; (iv) it allows for power savings; (v) it is not tied to TDP, and so can be adapted to other thermal methods. In its current state, the CHD data processing is not yet fully automated.  相似文献   
109.
Leaf litter decomposition and nutrient release patterns from five common multipurpose tree species—viz., Artocarpus heterophyllus, Mangifera indica, Areca catechu, Citrus sp., and Tamarindus indica, found in homegardens of Mizoram—were evaluated using a litter bag technique. The result of the study indicates a varying pattern of decomposition and nutrient release (N&P) among the species. Citrus sp. and T. indica were found to be the most labile species with comparatively much higher decay constant and faster nutrient release. Initial nitrogen concentration, lignin content, and lignin/N ratio of foliage litter showed significantly higher (p < .01) correlation with the decay coefficient and were found to be the important determinants in the decay process. The initial slow release and immobilization of N in A. heterophyllus and M. indica leaf litter reflect their potential as a source of nitrogen storage and effective mulching material. While litter from T. indica and Citrus sp. can provide the short-term nutrient need, foliage for the other three species may supply the long-term nutrient requirement for the understory crops in such agroforestry systems.  相似文献   
110.
Abstract

The effect of 0.2% emamectin benzoate (SLICE; Intervet/ Schering-Plough Animal Health, Roseland, New Jersey) administered in top-dressed, pelleted commercial fish feed was evaluated for control of freshwater Argulus sp. in goldfish Carassius auratus and koi carp, a variant of common carp Cyprinus carpio, in freshwater aquaria at 24–25°C. Sixteen individually housed goldfish were each exposed to 37 Argulus. The number of fish lice attached to each fish at the start of the experiment was not determined; however, the total number of motile fish lice in each aquarium (on fish and in the water) was determined at the start and end of each experiment. Eight goldfish were fed the control diet (0 μg · kg fish biomass?1 · d?1) and eight were fed the medicated diet (50 μg · kg fish biomass?1 · d?1) for seven consecutive days. After treatment, fish louse infestation in controls was 20.5 ± 1.5 (mean ± SE) lice per fish. No Argulus were found on fish in the treated group. In a separate experiment, 10 individually housed koi were each exposed to 128 Argulus. Five koi were fed the control diet and five were fed a low-dose medicated diet (5 μg · kg fish biomass?1 · d?1) for 7 d. After treatment, fish louse infestation among the controls was 14.6 ± 3.8 lice per koi. No Argulus were found on koi in the treated group. Hence, a 7-d regimen of oral emamectin benzoate controlled experimental infestation of Argulus when administered to goldfish at 50 μg · kg fish biomass?1 · d?1 and to koi at 5 μg · kg fish biomass?1 · d?1.

Received March 24, 2010; accepted January 17, 2011  相似文献   
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