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991.
Renato G Credie Francisco J Teixeira Neto Tatiana H Ferreira Antônio JA Aguiar Fabio C Restitutti José E Corrente 《Veterinary anaesthesia and analgesia》2010,37(3):240-249
ObjectiveTo investigate the effects of methadone on the minimum alveolar concentration of isoflurane (ISOMAC) in dogs.Study designProspective, randomized cross-over experimental study.AnimalsSix adult mongrel dogs, four males and two females, weighing 22.8 ± 6.6 kg.MethodsAnimals were anesthetized with isoflurane and mechanically ventilated on three separate days, at least 1 week apart. Core temperature was maintained between 37.5 and 38.5 °C during ISOMAC determinations. On each study day, ISOMAC was determined using electrical stimulation of the antebrachium (50 V, 50 Hz, 10 mseconds) at 2.5 and 5 hours after intravenous injection of physiological saline (control) or one of two doses of methadone (0.5 or 1.0 mg kg?1).ResultsMean (±SD) ISOMAC in the control treatment was 1.19 ± 0.15% and 1.18 ± 0.15% at 2.5 and 5 hours, respectively. The 1.0 mg kg?1 dose of methadone reduced ISOMAC by 48% (2.5 hours) and by 30% (5 hours), whereas the 0.5 mg kg?1 dose caused smaller reductions in ISOMAC (35% and 15% reductions at 2.5 and 5 hours, respectively). Both doses of methadone decreased heart rate (HR), but the 1.0 mg kg?1 dose was associated with greater negative chronotropic actions (HR 37% lower than control) and mild metabolic acidosis at 2.5 hours. Mean arterial pressure increased in the MET1.0 treatment (13% higher than control) at 2.5 hours.Conclusions and clinical relevanceMethadone reduces ISOMAC in a dose-related fashion and this effect is lessened over time. Although the isoflurane sparing effect of the 0.5 mg kg?1 dose of methadone was smaller in comparison to the 1.0 mg kg?1 dose, the lower dose is recommended for clinical use because it results in less evidence of cardiovascular impairment. 相似文献
992.
Computing of landscape pattern metrics from spectrally classified digital images is becoming increasingly common. Recently, object-orientated image classification is being seen as an alternative and is tending to replace pixel-based approaches. However, object-based methods are likely to influence and produce biases in the results of these spatial analyses. In this study, the sensitivity of 85 landscape metrics to different classification methods and parameters are analyzed. A Landsat image of a complex mountainous forest region of Mexico was classified using pixel-based and object-based approaches. Nine object-based classified images were obtained using a region-growing algorithm based upon different segmentation parameters. Pixel-based classified images were smoothed using different methods (majority filtering, sieving and clumping). Accuracy assessment was carried such that classified images with similar accuracy were compared. Landscape metrics were then derived from the different classified images and compared through a coefficient of variation computing. Almost all the metrics showed variability due to classification and post-processing methods, particularly core area metrics and some proximity and contagion/interspersion indices. Caution must be observed when comparing values of metrics derived from images with slight differences in their characteristics or in the way they have been processed as, for example, in landscape monitoring studies based upon multidate imagery. 相似文献
993.
Species within the genus Hibiscus (Malvaceae) are herbaceous or woody plants, annuals or perennials. Within the genus, most of the domesticated species are grown as ornamentals, and the most widely exploited is Hibiscus rosa-sinensis, which is particularly variable with respect to flower colour and shape. H. rosa-sinensis is thought to have originated following hybridization between two species complexes endemic to different geographic locations. 相似文献
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Schizochytrium as a replacement for fish oil in a fishmeal free diet for jade perch,Scortum barcoo (McCulloch & Waite)
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Stijn Van Hoestenberghe Charles‐Aimé Fransman Tom Luyten Daniel Vermeulen Ivo Roelants Saskia Buysens Bruno M. Goddeeris 《Aquaculture Research》2016,47(6):1747-1760
A 10‐week trial was conducted to determine the response of juvenile jade perch Scortum barcoo on the replacement of dietary fish oil (FO) in a fishmeal free diet. Three iso‐nitrogenous, isocaloric and isolipidic diets were formulated, each containing a different primary fat source: FO, linseed oil (LO), and a mixture of Schizochytrium and LO. The substitution of FO with the mixture of Schizochytrium and LO did not cause a difference in growth. However, there was an 8% reduction in weight gain in fish fed dietary LO, indicating that juvenile jade perch do require a minimal concentration of dietary n‐3 highly unsaturated fatty acids (HUFA). Fish fed the Schizochytrium diet stored more efficient n‐3 HUFA and in particular DHA in their flesh, and retained a higher fillet recovery compared to fish fed FO. In addition, we demonstrated that jade perch are able to produce both n‐3 HUFA and n‐6 HUFA when dietary PUFA are present. Fish fed the LO diet for 10 weeks contained the lowest amount of n‐3 HUFA in fillets among dietary treatment groups. However, feeding these fish the Schizochytrium diet for an additional 4 weeks increased the n‐3 HUFA content towards the same concentration of n‐3 HUFA found in the flesh of fish fed FO, without affecting the sensory properties of the fillets. In contrary, feeding the Schizochytrium diet for a continuous period of 14 weeks lowered overall sensory property scores. 相似文献
998.
Fatty acid utilization during the early larval stages of Florida pompano (Trachinotus carolinus) and Common snook (Centropomus undecimalis)
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Marion R Hauville Kevan L Main Hervé Migaud J. Gordon Bell 《Aquaculture Research》2016,47(5):1443-1458
The pattern of conservation and loss of fatty acids from the yolk sac during the endogenous feeding period and subsequent starvation was studied in pompano and snook larvae. Fundamental information on the early fatty acid dynamic and mobilization of pompano and snook larvae was collected. In both species, fatty acids were utilized as an energy source after hatching. Mono‐unsaturated fatty acids were catabolized, while saturated and poly‐unsaturated fatty acids were conserved. High levels of arachidonic acid (ARA) in pompano and snook eggs, as well as selective retention in the unfed larvae suggest a high dietary requirement for this fatty acid during the early stages of larval development. The effect of an ARA supplementation was therefore investigated in snook larvae at the rotifer feeding stage. The fatty acid profile of the larvae was successfully influenced to match that of wild eggs; however, no significant improvement in growth or survival was observed. Future research should be carried out over a longer period of time and include factors related to stress resistance. 相似文献
999.
Evaluation of pea protein concentrate as partial replacement of fish meal in practical diets for juvenile tench (Tinca tinca L.)
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Álvaro González‐Rodríguez Jesús D Celada José M Carral María Sáez‐Royuela Juan B Fuertes 《Aquaculture Research》2016,47(9):2825-2834
With the aim to evaluate different replacement levels of fish meal (FM) by pea protein concentrate (PPC) on survival, growth performance and body composition of juvenile tench (Tinca tinca), a 90‐day experiment was conducted with 6‐month‐old juveniles. Four practical diets (50% crude protein) differing in the level of replacement of FM protein by PPC protein were tested: 0% (control), 25%, 35% or 45%, corresponding to 0, 207.5, 290.4 or 373.3 g PPC kg?1 diet respectively. Survival rates ranged from 96.4% to 98.5%. The 25% and 35% replacement diets resulted in similar growth values (P > 0.05) to those obtained with the control diet (average of the three feeding treatments: 57.57 mm total length, 2.48 g weight and 1.87% day?1 specific growth rate). The 45% replacement diet had the lowest growth (P < 0.05). Fish with externally visible deformities ranged from 0% to 1.5%. The relation among amino acid profiles of the diets, body composition, growth performance of juveniles and amino acid requirements of other fish species is discussed. An amount of 290.4 g PPC kg?1 diet (35% replacement of FM protein) can be included in juvenile tench diets without impairing growth performance. 相似文献
1000.
Growth performance of juvenile pacu (Piaractus mesopotamicus) and dourado (Salminus brasiliensis) fed with lyophilized bovine colostrum
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Raul Machado‐Neto Debora Botequio Moretti Wiolene Montanari Nordi Thaline Maira Pachelli da Cruz José Eurico Possebon Cyrino 《Aquaculture Research》2016,47(11):3551-3557
Growth performance was evaluated in juvenile pacu (Piaractus mesopotamicus) and dourado (Salminus brasiliensis) fed diets containing 0%, 10% and 20% of lyophilized bovine colostrum for 60 days. The performance variables of weight gain, relative weight gain, feed intake, feed conversion ratio, specific growth rate, total protein intake and protein efficiency ratio were evaluated as well as apparent digestibility coefficients of protein and energy in the diets. Inclusion of bovine colostrum did not induce differences in the performance of pacu and dourado (P > 0.05), indicating that the diets were adequate and met the nutritional needs of the juveniles. The protein digestibility in both species was improved with the inclusion of the bovine lacteal secretion. Based on the variables studied, the diets with lyophilized bovine colostrum inclusion were nutritionally suitable for both pacu and dourado indicating the possibility to use this lacteal secretion as a partial substitute of dietary protein. 相似文献