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991.
Enhanced Salmonella surveillance programmes in poultry were implemented in all European Member States, with minimum prevalence targets for a list of targeted serotypes to safeguard food and public health. Based on the Belgian Salmonella surveillance programme and focusing on poultry, the overarching aim of this study was to highlight possible Salmonella transmissions across the food chain (FC). For this purpose, firstly, the prevalence patterns of Salmonella (targeted and the most prevalent non-targeted) serotypes along the FC were described over time. Secondly, the effectiveness of the control measures against vertical transmission (breeders to 1-day-old broiler and layer chicks) was indirectly assessed by looking into the odds of targeted serotypes detection. Thirdly, it was appraised if Salmonella prevalence can significantly increase during broilers and layers production. In addition, it was tested if being tested negative at the end of production in broilers when tested positive at the entrance is serotype dependent (targeted vs. non-targeted serotypes). Results showed that, firstly, the prevalence patterns of the listed serotypes were inconstant over time and across the FC. Secondly, the odds of Salmonella targeted serotype detection in 1-day-old broiler and in 1-day-old layer flocks were lower than in breeder flocks while, thirdly, infection during broiler and layer production can lead to significant increase in positivity in subsequent samples. Finally, being infected by a targeted or by non-targeted serotype at the entrance of the flock poorly reflects the Salmonella status at the end of production. Note that this study did not make a distinction between the different sources of contamination and the effects of sampling methods and isolation methods should be subject to further investigation.  相似文献   
992.
Methods of calculating and reporting dose intensity (DI) of CHOP-based protocols in the veterinary literature vary. The goal of this retrospective study is to examine the prognostic significance of the average percentage of planned DI received in a cohort of canine T-cell lymphoma patients treated with a modified CHOP protocol with corresponding toxicity and efficacy data. Our data set of 40 dogs was analysed using various previously published methods for calculating DI. Median progression-free survival and overall survival were 91 and 196 days, respectively. Receiving a higher percentage of planned DI was not found to be associated with patient outcome. Outcomes remain poor for dogs with T-cell lymphoma treated with CHOP-based chemotherapy irrespective of received DI. Standard methods of DI calculation and reporting should be adopted in veterinary oncology to enable repeatable and rigorous comparisons of published chemotherapy protocols and to ascertain the potential prognostic relevance of DI in canine lymphoma patients.  相似文献   
993.
994.
The existing diversity within poultry systems affects the potential risk of infectious disease introduction and spread. Population data on the level of biosecurity and between-farm contacts is scarce, despite its importance for identifying possible routes of disease transmission. A study was carried out in Belgium to investigate and differentiate professional and hobby poultry sites based on their biosecurity levels and farm movements. Questionnaire data from a total of 37 professional poultry farms, 19 hatcheries and 286 hobby poultry sites were analyzed using a combination of a linear scoring system, a Categorical principal component analysis (CATPCA) and a Two-Step cluster analysis (TSCA). In general, the level of biosecurity was lower in hobby poultry flocks, mainly due to the poor confinement against the outdoor environment and the poor infrastructural hygiene. Most Belgian professional poultry farms and hatcheries had an acceptable level of adoption of standard biosecurity practices, however less attention was given to the way transportation vehicles and employers were brought onto farms and professional visitors welcomed. Considerable variation in the movements and in the structure of the networks arising from these movements was found. Movement frequencies were higher at professional farms compared to hobby farms. Results showed that multiple category farming systems had the highest total movement frequencies. Monthly frequencies of professional visits often exceeded those of poultry and egg movements. Professional and hobby poultry sites were also connected, but movements of poultry and eggs were found only to occur from professional to hobby sites. However, hobby poultry keepers were personally purchasing the poultry and eggs on the professional poultry sites. Six groups of poultry sites were differentiated, which are interpreted as very low to very high risk groups, based on the potential of infectious disease introduction and spread.  相似文献   
995.
Identification of nasal neoplasia extension and tumor staging in dogs is most commonly performed using computed tomography (CT), however magnetic resonance imaging (MRI) is routinely used in human medicine. A prospective pilot study enrolling six dogs with nasal neoplasia was performed with CT and MRI studies acquired under the same anesthetic episode. Interobserver comparison and comparison between the two imaging modalities with regard to bidimensional measurements of the nasal tumors, tumor staging using historical schemes, and assignment of an ordinal scale of tumor margin clarity at the tumor‐soft tissue interface were performed. The hypotheses included that MRI would have greater tumor measurements, result in higher tumor staging, and more clearly define the tumor soft tissue interface when compared to CT. Evaluation of bone involvement of the nasal cavity and head showed a high level of agreement between CT and MRI. Estimation of tumor volume using bidimensional measurements was higher on MRI imaging in 5/6 dogs, and resulted in a median tumor volume which was 18.4% higher than CT imaging. Disagreement between CT and MRI was noted with meningeal enhancement, in which two dogs were positive for meningeal enhancement on MRI and negative on CT. One of six dogs had a higher tumor stage on MRI compared to CT, while the remaining five agreed. Magnetic resonance imaging resulted in larger bidimensional measurements and tumor volume estimates, along with a higher likelihood of identifying meningeal enhancement when compared to CT imaging. Magnetic resonance imaging may provide integral information for tumor staging, prognosis, and treatment planning.  相似文献   
996.

Objective

The evaluation of alfaxalone as a premedication agent and intravenous anaesthetic in pigs.

Study design

Prospective, clinical trial.

Animals

Nine healthy, 6–8-week-old female Landrace pigs weighing 22.2 ± 1.0 kg, undergoing epidural catheter placement.

Methods

All pigs were premedicated with 4 mg kg?1 alfaxalone, 40 μg kg?1 medetomidine and 0.4 mg kg?1 butorphanol administered in the cervical musculature. Sedation was subjectively scored by the same observer from 1 (no sedation) to 10 (profound sedation) prior to induction of anaesthesia with alfaxalone intravenously to effect. All pigs were maintained on alfaxalone infusions with the rate of administration adjusted to maintain appropriate anaesthetic depth. Quality of induction was scored from 1 (poor) to 3 (smooth) and basic cardiorespiratory variables were recorded every 5 minutes during anaesthesia. Results are reported as mean ± standard deviation or median (range) as appropriate.

Results

Sedation scores were 9 (7–10). Inductions were smooth in all pigs and cardiovascular variables remained within normal limits for the duration of anaesthesia. The induction dose of alfaxalone was 0.9 (0.0–2.3) mg kg?1. Three pigs did not require additional alfaxalone after premedication to facilitate intubation.

Conclusions and clinical relevance

Intramuscular alfaxalone in combination with medetomidine and butorphanol produced moderate to deep sedation in pigs. Alfaxalone produced satisfactory induction and maintenance of anaesthesia with minimal cardiovascular side effects. Appropriate monitoring of pigs premedicated with this protocol is required as some pigs may become anaesthetized after intramuscular administration of this combination of drugs.  相似文献   
997.
Objective: To determine the survival rates and factors affecting survival in small ruminants and camelids attacked by dogs. Design: Retrospective study. Setting: Two university teaching hospitals. Animals: Thirty goats, 28 sheep, 3 alpacas, and 1 llama. Measurements and main results: Medical records were reviewed to obtain signalment, time between injury and admission, hospitalization length, lesion site, treatment, complications, survival rate, and cost. Follow‐up information was obtained by telephone conversation with the owner. Sixty‐two patients met the inclusion criteria. Six animals were euthanized at admission and thus excluded. Of the 56 animals that were treated, 43 (77%) were discharged, 5 (9%) died, and 8 (14%) were euthanized. Animals that had thoracic or abdominal injuries, required surgery, or received more potent analgesic therapy were less likely to survive to discharge from hospital compared with animals that did not. Complications developed in 50 (82%) animals. Animals with respiratory complications were also less likely to survive to discharge from hospital than animals that did not. Long‐term follow up was available on 38/43 (88%) animals that were discharged. Thirty‐five of 38 (92%) animals were discharged and recovered from their injuries and 5 animals had long‐term complications. Conclusions: Small ruminants and camelids that are attacked by dogs have a good prognosis for short‐term survival. Short‐term survival is affected by lesion location and complications.  相似文献   
998.
OBJECTIVE: To evaluate the effect ventriculocordectomy (VC) for treatment of recurrent laryngeal neuropathy (RLN) on exercise performance and owner satisfaction in a mixed-breed population of horses. STUDY DESIGN: Retrospective study. ANIMALS: Adult horses (n=92) with a history of abnormal respiratory noise and RLN. METHODS: Retrospective analysis of horse that had unilateral VC (and contralateral ventriculectomy in 63 horses) for treatment of idiopathic RLN. Owners/trainers completed a questionnaire about complications and outcome at least 1 year after surgery. Performance index was determined using race records for previously raced Thoroughbreds to evaluate outcome. RESULTS: Clinical signs included abnormal exercise-induced respiratory noises (noises; 52%), poor performance (11%), and noises and poor performance (37%). The median preoperative resting endoscopic grade of laryngeal function was Havemeyer grade III.1 (mild asymmetry). No discharge from the laryngotomy 1 week postoperatively occurred in 62% horses, 22% coughed after surgery, 66% made no noises, 9% continued to make noises at the canter, 21% made noise at the gallop, and 4% of owners were unsure whether noises were present. Ninety-three percent of horses returned to full work after surgery. Overall, 86% of owners considered the surgery worthwhile, 3% did not consider it worthwhile, and 11% were unsure. Surgery had a significantly beneficial effect on the racing performance index in Thoroughbreds (P=.004). CONCLUSIONS: VC is a useful alternative to laryngoplasty for selected cases of RLN and is associated with a positive effect on exercise performance, a low postoperative complication rate, and a high rate of owner satisfaction. CLINICAL RELEVANCE: Unilateral VC should be considered as a sole treatment in horses with low grades of RLN.  相似文献   
999.
1000.
High-resolution images of Mercury's surface from orbit reveal that many bright deposits within impact craters exhibit fresh-appearing, irregular, shallow, rimless depressions. The depressions, or hollows, range from tens of meters to a few kilometers across, and many have high-reflectance interiors and halos. The host rocks, which are associated with crater central peaks, peak rings, floors, and walls, are interpreted to have been excavated from depth by the crater-forming process. The most likely formation mechanisms for the hollows involve recent loss of volatiles through some combination of sublimation, space weathering, outgassing, or pyroclastic volcanism. These features support the inference that Mercury's interior contains higher abundances of volatile materials than predicted by most scenarios for the formation of the solar system's innermost planet.  相似文献   
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