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Among birds, the Procellariiform seabirds (petrels, albatrosses, and shearwaters) are prime candidates for using chemical cues for individual recognition. These birds have an excellent olfactory sense, and a variety of species nest in burrows that they can recognize by smell. However, the nature of the olfactory signature--the scent that makes one burrow smell more like home than another--has not been established for any species. Here, we explore the use of intraspecific chemical cues in burrow recognition and present evidence for partner-specific odor recognition in a bird. 相似文献
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Gabrielle Claing Pascal Dubreuil Julie Ferland Martine Bernier Julie Arsenault 《Canadian journal of veterinary research》2021,85(3):229
The growing number of honey bee colonies and beekeepers in Canada has led to a great diversity of beekeeping practices. All beekeeping operations, however, need to implement consistent management measures for the control of diseases. The objective of this study was to document the actual disease management practices of beekeeping productions in southwestern Quebec, Canada. A survey was conducted to describe management practices used by 15 beekeepers who own 1824 colonies in that area. Data were obtained by telephone interviews. When infectious diseases were suspected, beekeepers generally avoided using potentially toxic acaricides and chemical treatments associated with antimicrobial resistance and instead used preventive, physical or management methods, although laboratory diagnosis was rarely used. This study highlights the wide variety of operation sizes, activities, and disease management strategies among beekeepers in southwestern Quebec. It identifies the need to encourage the use of services available to them and to propose a standardized preventive medical approach for field veterinarians to avoid the spread of infectious diseases. 相似文献
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Sibanda S Hughes JM Pawson PE Kelly G Bellenger CR 《Veterinary anaesthesia and analgesia》2006,33(4):246-257
OBJECTIVE: To evaluate the efficacy of preoperative extradural bupivacaine and morphine in attenuating the stress response in dogs undergoing femoro-tibial joint surgery. STUDY DESIGN: Prospective clinical study. Animal population Twelve client-owned dogs undergoing surgery for either repair of cruciate ligament rupture (ten) or correction of luxating patella (two). Body masses ranged from 12 to 45 kg (mean: 28.58 +/- 18.38). Age ranged from 19 to 121 months (mean: 66.5 +/- 49.5). MATERIALS AND METHODS: Six of the dogs received extradural bupivacaine (up to 1.5 mg kg(-1)) combined with morphine (0.1 mg kg(-1); ED) while the other six received no extradural analgesia (C). The levels of cortisol, acute phase proteins (APPs), and red and white blood cell variables were measured in both groups of dogs before, and at various times after surgery. Pain was also assessed at various times after surgery. The number of postoperative morphine doses required, and their time of administration, was recorded for each animal. Method of statistical analysis Data were analysed using anova for repeated measures with p-values of <0.05 considered significant. RESULTS: Cortisol levels in the ED group were significantly (p < 0.05) lower than those of the control group at the end of surgery. No statistically significant differences were found in APPs or red and white cell variables between dogs receiving, and those not receiving extradural bupivacaine and morphine. Four dogs in the control group and one in the ED group required postoperative morphine. CONCLUSIONS AND CLINICAL RELEVANCE: Pre-emptive extradural bupivacaine and morphine was effective in lowering the neuroendocrine stress response (cortisol) in the ED group but had no effect on the inflammatory response (acute phase response). 相似文献
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Eva Rioja Luis M. Rubio-Martínez Gabrielle Monteith Carolyn L. Kerr 《Canadian journal of veterinary research》2013,77(4):273-280
The objectives of this study were to determine the analgesic and motor effects of a high-volume intercoccygeal epidural injection of bupivacaine at 2 concentrations in cows. A prospective, randomized, blinded, crossover trial was conducted on 6 adult cows. An indwelling epidural catheter was placed in the first intercoccygeal space and advanced 10 cm cranially. All the cows received 3 treatments with a washout period of 48 h: saline (control), 0.125% bupivacaine (high dose), or 0.0625% bupivacaine (low dose), at a final volume of 0.15 mL per kilogram of body weight, infused manually into the epidural space over a period of 15 min. The anal and tail tone and motor deficits of the pelvic limbs were evaluated in 5 of the cows with use of a numerical rating scale and a visual analogue scale (VAS). Sensory block was assessed in 4 of the cows by the response to needle pricks in different regions with the use of a VAS. Measurements were obtained before and at different time points after injection, up to 360 min. Analysis of variance for repeated measures and post-hoc Tukey’s and Dunnett’s tests were used. Differences were considered significant when the P-value was ≤ 0.05. One cow became recumbent 6 h after injection. Anal and tail tones were significantly decreased and motor deficits of the pelvic limbs were significantly increased after bupivacaine treatment compared with control treatment. The overall mean VASpain scores ± standard deviation were 66 ± 8 after control treatment, 52 ± 5 after low-dose bupivacaine treatment, and 43 ± 5 after high-dose bupivacaine treatment. The pain scores were significantly lower in caudal regions up to the saphenous nerve after high-dose bupivacaine treatment compared with control treatment and significantly lower in the anus, vulva, and tail after low-dose bupivacaine treatment compared with control treatment. Thus, analgesia with moderate motor deficits of the pelvic limbs may be obtained with 0.125% bupivacaine administered epidurally. 相似文献
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C. Bessou B. Mary J. Léonard M. Roussel E. Gréhan B. Gabrielle 《European Journal of Soil Science》2010,61(3):348-363
Nitrous oxide (N2O) emissions comprise the major share of agriculture's contribution to greenhouse gases; however, our understanding of what is actually happening in the field remains incomplete, especially concerning the multiple interactions between agricultural practices and N2O emissions. Soil compaction induces major changes in the soil structure and the key variables controlling N2O emissions. Our objective was to analyse the ability of a process‐based model (Nitrous Oxide Emissions (NOE)) to simulate the impact of soil compaction on N2O emission kinetics obtained from field experiments. We used automatic chambers to continuously monitor N2O and CO2 emissions on uncompacted and compacted areas in sugar beet fields during 2 years. Soil compaction led to smaller CO2 emissions and larger N2O emissions by inducing anoxic conditions favourable for denitrification. Cumulative N2O emissions during the crop cycles were 944 and 977 g N ha−1 in uncompacted plots and 1448 and 1382 g N ha−1 in compacted plots in 2007 and 2008, respectively. The NOE model ( Hénault et al., 2005 ) simulated 106 and 138 g N2O‐N ha−1 in uncompacted plots and 1550 and 650 g N2O‐N ha−1 in compacted plots in 2007 and 2008, respectively, markedly under‐estimating the nitrification rates and associated N2O emissions. We modified the model on the basis of published results in order to better simulate nitrification and account for varying N2O fractions of total end‐products in response to varying soil water and nitrate contents. The modified model (NOE2) better predicted nitrification rates and N2O emissions following fertilizer addition. Using a fine vertical separation of soil layers of configurable, but constant, thickness (1 cm) also improved the simulations. NOE2 predicted 428 and 416 g N‐N2O ha−1 in uncompacted plots and 1559 and 1032 g N‐ N2O ha−1 in compacted plots in 2007 and 2008, respectively. These results show that a simple process‐based model can be used to predict successfully the post‐fertilizer addition kinetics of N2O emissions and the impact of soil compaction on these emissions. However, large emissions later on during the cropping cycle were not captured by the model, emphasizing the need for further research. 相似文献
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Rioja E Sinclair M Chalmers H Foster RA Monteith G 《Veterinary anaesthesia and analgesia》2012,39(2):190-200
ObjectiveTo compare success and complication rates, based on staining of nerves and other structures, among three techniques of paravertebral brachial plexus blockade (PBPB) in dogs.Study designProspective randomized design.AnimalsA total of 68 thoracic limbs from 34 dogs.MethodsLimbs were randomly assigned to blind (BL) (n = 24), nerve stimulator-guided (NS) (n = 21) or ultrasound-guided (US) (n = 23) technique. Injections were made with 0.3 mL kg?1 of lidocaine mixed with new methylene blue. Time to perform each block and current used during NS technique were recorded. Dogs were anesthetized during the blocks and euthanized once completed. Dissections were performed to evaluate staining of nerves, spinal cord, mediastinum, pleura and vessels. An anova and Tukey adjustment for time, logistic regression for association between current and nerve staining and a generalized linear mixed model for staining of different structures were used. Significance was considered when p ≤ 0.05.ResultsThe median (range) number of nerves stained was 2 (0–4) with BL, 1 (0–3) with NS and 1 (0–4) with US guided technique. No significant differences in staining of C6, C8 and T1 or other structures were found among techniques. Nerve C7 was more likely to be stained by BL (p = 0.05). Time to perform the blocks was significantly different among techniques, with mean ± SD duration in minutes of 3.6 ± 1.8 with BL, 6.3 ± 2.7 with US and 12.2 ± 5 with NS. The most common complication was staining of the spinal cord (29%, 38% and 39% with BL, NS and US, respectively).ConclusionsSuccess rates were low and complication rates were relatively high, based on staining, with the three techniques.Clinical relevanceThe use of more advanced techniques for PBPB in dogs is not justified according to this study. Clinical significance of the complications encountered in this study should be evaluated. 相似文献
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