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排序方式: 共有879条查询结果,搜索用时 171 毫秒
871.
Larissa B Cardozo DVM Ricardo M Almeida† DVM PhD Diplomate CBCAV Levi C Fiúza‡ DVM & Paula D Galera DVM PhD 《Veterinary anaesthesia and analgesia》2009,36(4):396-400
Objective To evaluate the quality of brachial plexus blockade with 0.75% ropivacaine in domestic chickens.
Study design Prospective experimental trial.
Animals Six 30-week-old female chickens, weighing 4.5 ± 0.4 kg.
Methods Six brachial plexus injections were performed after anesthetic induction with isoflurane. After achieving adequate muscle relaxation, the animals were positioned in dorsal recumbency and injected with ropivacaine (1 mL kg−1 ). The birds recovered and assessments of motor function and response to pinch were scored every 5 minutes for 180 minutes. The scores were from zero (no response) to three (greatest response). The scores over time were analyzed using a Wilcoxon nonparametric test with statistical significance accepted if p ≤ 0.05.
Results There was a significant difference ( p < 0.05) from 15 to 130 minutes and 15 to 120 minutes for motor and sensory blocks, respectively. The onset of both blocks took 15 minutes and the effective periods of sensory and motor anesthesia were 105 and 115 minutes, respectively. Comparison between blocks at different times did not demonstrate significant differences ( p > 0.05).
Conclusions and clinical relevance No complications were observed after the technique. Brachial plexus blockade with 0.75% ropivacaine is a simple and effective technique for procedures on the thoracic limb of domestic chickens. 相似文献
Study design Prospective experimental trial.
Animals Six 30-week-old female chickens, weighing 4.5 ± 0.4 kg.
Methods Six brachial plexus injections were performed after anesthetic induction with isoflurane. After achieving adequate muscle relaxation, the animals were positioned in dorsal recumbency and injected with ropivacaine (1 mL kg
Results There was a significant difference ( p < 0.05) from 15 to 130 minutes and 15 to 120 minutes for motor and sensory blocks, respectively. The onset of both blocks took 15 minutes and the effective periods of sensory and motor anesthesia were 105 and 115 minutes, respectively. Comparison between blocks at different times did not demonstrate significant differences ( p > 0.05).
Conclusions and clinical relevance No complications were observed after the technique. Brachial plexus blockade with 0.75% ropivacaine is a simple and effective technique for procedures on the thoracic limb of domestic chickens. 相似文献
872.
Bisogno F Mascoti L Sanchez C Garibotto F Giannini F Kurina-Sanz M Enriz R 《Journal of agricultural and food chemistry》2007,55(26):10635-10640
A structure-antifungal activity relationship (SAR) study of 22 related cinnamic acid derivatives was carried out. Attention was focused on the antifungal activities exhibited against Aspergillus flavus, Aspergillus terreus, and Aspergillus niger. (E)-3-(4-methoxy-3-(3-methylbut-2-enyl)phenyl)acrylic acid (16) exhibited antifungal activity against A. niger, comparable to that of miconazole and a significant antifungal effect against A. flavus and A. terreus as well. A structure-activity relationship (SAR) study of related cinnamic acid derivatives has allowed a model to be proposed for the recognition of the minimal structural requirements for the antifungal effect in this series. 相似文献
873.
Ana C. Luz Cunha Vitor de A. Pontinha Maria Alcina M. de Castro Simone Sühnel Sthefanie C. Medeiros ngela M. Moura da Luz Ricardo Harakava Leonardo Tachibana Danielle F. Mello Naissa M. Danielli Alcir L. Dafre Aimê R. M. Magalhes Jos Luiz P. Mourio 《Journal of fish diseases》2019,42(3):455-463
Perkinsus spp. have been detected in various bivalve species from north‐east Brazil. Santa Catarina is a South Brasil state with the highest national oyster production. Considering the pathogenicity of some Perkinsus spp., a study was carried out to survey perkinsosis in two oyster species cultured in this State, the mangrove oyster Crassostrea gasar and the Pacific oyster Crassostrea gigas. Sampling involved eight sites along the state coast, and oyster sampling was collected during the period between January 2013 and December 2014. For the detection of Perkinsus, Ray's fluid thioglycollate medium (RFTM) and histology were used, and for the identification of the species, PCR and DNA sequencing were used. Perkinsus spp. was found by RFTM in C. gigas and C. gasar from São Francisco do Sul. This pathology was also detected in C. gasar from Balneário Barra do Sul both, by RFTM and histology. Perkinsus marinus was identified in C. gigas and C. gasar from São Francisco do Sul and Perkinsus beihaiensis in C. gasar from Balneário Barra do Sul. This is the first report of P. marinus in C. gigas from South America. Results of this preliminary study suggest that both oyster species tolerate the species of Perkinsus identified, without suffering heavy lesions. 相似文献
874.
Elias Welengane Ricardo Yuji Sado lvaro Jos de Almeida Bicudo 《Aquaculture Nutrition》2019,25(6):1272-1280
This research assessed four levels of crude protein—200, 250, 300 and 350 g/kg—associated with two crude lipid concentrations—110 and 140 g/kg—in diets for juveniles of tambatinga (♀Colossoma macropomum × ♂Piaractus brachypomus) over 63 days. The fish (15.2 ± 0.2 g) were distributed in 24–160 L tanks (11 fish/tank) in a 4 × 2 completely randomized factorial design (n = 3). Increasing the lipid content in the diets reduced (p < 0.05) the protein requirements for weight gain from 326 g/kg (diets with 110 g/kg LIP) to 255 g/kg (diets with 140 g/kg). Protein retention in the fish increased (p < 0.05) when they were fed up to 293 g/kg CP and 140 g/kg LIP; in the diets with 110 g/kg LIP, protein retention decreased linearly (p < 0.05) as the protein content in the diets increased. Feed efficiency increased (p < 0.05) when the fish received up to 308 g/kg CP regardless of lipid concentration (p > 0.05). In conclusion, tambatinga juveniles at 15–120 g have a minimum requirement of 255 g/kg CP and 140 g/kg CL and a protein:energy ratio of 17.4 g CP kJ/digestible energy (DE). 相似文献
875.
Robert A. McConnaughey Jan G. Hiddink Simon Jennings C. Roland Pitcher Michel J. Kaiser Petri Suuronen Marija Sciberras Adriaan D. Rijnsdorp Jeremy S. Collie Tessa Mazor Ricardo O Amoroso Ana M. Parma Ray Hilborn 《Fish and Fisheries》2020,21(2):319-337
Bottom trawling accounts for almost one quarter of global fish landings but may also have significant and unwanted impacts on seabed habitats and biota. Management measures and voluntary industry actions can reduce these impacts, helping to meet sustainability objectives for fisheries, conservation and environmental management. These include changes in gear design and operation of trawls, spatial controls, impact quotas and effort controls. We review nine different measures and actions and use published studies and a simple conceptual model to evaluate and compare their performance. The risks and benefits of these management measures depend on the extent to which the fishery is already achieving management objectives for target stocks and the characteristics of the management system that is already in place. We offer guidance on identifying best practices for trawl‐fisheries management and show that best practices and their likelihood of reducing trawling impacts depend on local, national and regional management objectives and priorities, societal values and resources for implementation. There is no universal best practice, and multiple management measures and industry actions are required to meet sustainability objectives and improve trade‐offs between food production and environmental protection. 相似文献
876.
Essential oil of Aloysia triphylla in Nile tilapia: anaesthesia,stress parameters and sensory evaluation of fillets 下载免费PDF全文
Rafael Rivas Teixeira Renilde Cordeiro de Souza Artur Cedraz Sena Bernardo Baldisserotto Berta Maria Heinzmann Ricardo David Couto Carlos Eduardo Copatti 《Aquaculture Research》2017,48(7):3383-3392
The optimum concentration of anaesthetic used to facilitate fish handling can be determined based on induction and recovery time, among other factors. This study aimed to evaluate the effectiveness of the essential oil of Aloysia triphylla (EOAT) as an anaesthetic in the handling of Nile tilapia juveniles. Nile tilapias exemplars were immersed at 0 (control group), 10, 20, 30, 40, 80, 150, 300 and 450 μL L?1 EOAT to evaluate sedation, anaesthesia and recovery time. The stress response was evaluated by the determination of plasma glucose, cortisol, lactate and paraoxonase levels in anaesthetized (300 μL L?1 EOAT) and non‐anaesthetized fish. Fillets from both groups were evaluated for organoleptic characteristics (taste and odour). Concentrations of 80–450 μL L?1 EOAT were effective in inducing anaesthesia. There was a significant reduction in plasma cortisol levels one hour after handling in individuals anaesthetized with 300 μL L?1 EOAT compared to the control group. Tasters did not detect differences in fillet taste and odour between fish exposed and not exposed to EOAT. A concentration of 300 μL L?1 EOAT is recommended for handling Nile tilapia because it presents good anaesthetic induction and recovery times, causes a reduction in plasma cortisol levels one hour after handling and does not affect the taste or odour of the fillets. 相似文献
877.
Transport of juvenile dusky grouper Epinephelus marginatus under different packing densities: Metabolic and haematological responses 下载免费PDF全文
Paola Milena Pereira‐Cardona Viviana Lisboa Luis André Luz Barbas Ricardo Berteaux Robaldo 《Aquaculture Research》2017,48(10):5356-5362
The aim of this study was to investigate a suitable packing density for the transport of juvenile dusky grouper, Epinephelus marginatus, based on the evaluation of stress responses in blood. After acclimation, fish were placed in plastic bags and transported for 8 hr on paved road at densities of 28, 45 and 64 g/L. Water quality was monitored before and after transport. Blood was collected before, upon arrival (0 hr), after 2 and 24 hr of transport. Plasma cortisol, blood glucose, partial pressures of O2 (pO2) and CO2 (pCO2), blood pH and HCO3? were evaluated. Blood smears were prepared for the verification of leucocyte profile and neutrophils:lymphocyte ratio (N:L). Blood pCO2, pH and HCO3? increased significantly after transport for all treatments compared with pre‐transport. Glucose levels increased at the higher density whereas no effects were observed on plasma cortisol and pO2 levels. Upon arrival, all treatments showed lymphopenia and neutrophilia which increased N:L ratio. Although lymphopenia was observed in higher densities until 2 hr after transport, haematological parameters were fully restored within 24 hr post transport. Furthermore, no mortalities were observed throughout the experimental period. Based on the transient physiological changes observed in this study, juvenile dusky grouper can be safely transported in plastic bags for 8 hr at a density of up to 64 g/L. 相似文献
878.
Induced spermiation of Pimelodus britskii (Teleostei: Pimelodidae) during the reproductive period 下载免费PDF全文
Danielle Zanerato Damasceno Ricardo Andrei Krause Maurício Spagnolo Adames Giovano Neumann Anderson Gibathe Robie Allan Bombardelli Elizabeth Romagosa 《Aquaculture Research》2017,48(3):862-874
For the first time was characterized the semen of Pimelodus britskii, hormonally induced and non‐induced induced, during the reproductive period. The experiment 1 was conducted with 12 fish per month, divided into: (i) induced with Carp Pituitary Extract (CPE), and (ii) without hormonal induction (testes macerated). The experiment 2 was conducted, with 30 fish, divided into groups for comparison of different doses of CPE and human Chorionic Gonadotrophin (hCG; T1: control; T2: 3.0 mg kg?1 CPE; T3: 0.5 mg kg + 3.0 mg kg?1 CPE; T4: 0.5 mg kg?1 + 7.0 mg kg?1 CPE; T5: 200 UI kg?1 hCG), the same fish were used every month, and the semen was collected by abdominal massage. In both, experiments were assessed the sperm motility and velocity by means of the CASA software. In experiment 1, the concentration of spermatozoids was significantly increase by application of CPE compared untreated males. The volume and motility decreased gradually until the end of the experiment, the highest values were recorded for treatment induced (0.49 ± 0.25 mL and 62.18, respectively). The same occurred to Gonadosomatic Index, showing the smallest value at the end of the reproductive period. The fish from experiment 2 released reduced volume of watery semen (0.1 mL). The values of sperm concentration, motility velocity decreased gradually throughout the months. For P. britskii, the reproductive period influenced the production and sperm quality. Despite small seminal volume released the dose of 7.5 mg kg?1 of CPE proved effective. 相似文献
879.
Ricardo Martínez Silvia Mendoza Edilso Reguera Pedro Ortiz Jos de la Luz Martínez 《Cereal Chemistry》2001,78(2):107-110
The nixtamalization of the pericarp isolated from grains of corn was studied with 2, 5, 10, 20 and 40% Ca(OH)2 based upon the mass of the pericarp. For 2 and 5% Ca(OH)2 a small loss of the mass of the pericarp takes place quickly which is accompanied by an abrupt fall of the concentration of the OH‐ ions. A suitable kinetic model for the decrease of the mass of the pericarp is a two phases exponential equation. The second phase is the slowest and it depends on the quantity of Ca(OH)2 employed. 相似文献