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991.
992.
Milena W. Ferreira Felipe G. de Araujo Diego V. Costa Priscila V. Rosa Henrique C. P. Figueiredo Luis D. S. Murgas 《Journal of the World Aquaculture Society》2011,42(1):24-33
To investigate the impact of different dietary lipid sources on fillet composition and lipid transport, we conducted a feeding trial and evaluated the proximate composition of muscle tissue, fatty acid profiles, total cholesterol (in muscle and plasma), triglycerides, and lipoprotein concentrations in Nile tilapia, Oreochromis niloticus. Five semi‐purified diets, containing different oils (soybean – SO, corn – CO, linseed – LO, fish – FO, and olive – OO), were supplied to tilapia for 160 d. Fish fed with LO and FO diets had a lower percentage of total lipids in muscle compared with the others (P < 0.05). The highest percentage of protein was found in fish fed with FO diet (P < 0.05). The muscle fatty acid profile was influenced differently by diets (P < 0.05). The group supplemented with SO and CO had a higher concentration of 18:2n‐6, whereas the fish fed with LO diet had a higher level of 18:3n‐3 and those that received the FO diet had more 22:6n‐3 in comparison with those supplemented with vegetable oils. Plasma lipid transport was also affected by the diets: the fish fed with FO diet had higher total cholesterol and high‐density lipoprotein and lower very‐low‐density lipoprotein concentrations (P < 0.05). 相似文献
993.
E. A. Susyan N. D. Ananyeva E. G. Gavrilenko O. V. Chernova M. V. Bobrovskii 《Eurasian Soil Science》2009,42(10):1148-1155
In the mineral horizons of the soils under different southern taiga forests (oak, archangel spruce, and aspen in the Kaluzhskie
Zaseki Reserve of Kaluga region and the green moss spruce and spruce-broadleaved forests of the Zvenigorod Biological Station
of Moscow State University in Moscow region), the carbon content in the microbial biomass (Cmic), the rate of the basal respiration (BR), and the specific microbial respiration (qCO2= BR/Cmic) were determined. The Cmic content was measured using the method of substrate-induced respiration (SIR). In the upper humus horizons of the soils, the
Cmic content amounted to 762–2545 μg/g and the BR ranged from 1.59 to 7.55 μg CO2-C/g per h. The values of these parameters essentially decreased down the soil profiles. The portion of Cmic in the organic carbon of the humus horizons of the forest soils was 4.4 to 13.2%. The qCO2values increased with the depth in the soils of the Biological Station and did not change in the soils of the Reserve. The
pool of Cmic and Corg and the microbial production of CO2 (BR) within the forest soil profiles are presented. 相似文献
994.
995.
Pablo Vásquez Gassibe Raul Fraile Fabero María Hernández-Rodríguez Juan Andrés Oria-de-Rueda Felipe Bravo Oviedo Pablo Martín-Pinto 《Journal of Forest Research》2014,19(3):348-356
This study was aimed at describing post-fire mushroom production in a Mediterranean ecosystem dominated by Pinus pinaster Ait. in the northwest of Spain and assessing the results by classificatory models. During the autumn periods of 2003–2006, fruit bodies from 115 fungal taxa were collected in burned and unburned areas and were further grouped into the following categories: saprotrophic/mycorrhizal; and edible/non-edible. After wildfires, a significant reduction in the number of fungal species and fruit body biomass production was observed. Based on this relevant information, the first simple classificatory model for this aim is provided. Nine alternative models based on classifications according to combinations of edibility and functional groups were fitted, and four fruiting body biomass production classes were defined as possible responses. As explanatory factors, time after fire and climatic variables significantly related to fruit body production were included. The best predictive results were obtained for edible and edible-mycorrhizal models, for which the correct classification rate of production classes was between 92 and 85 %. Moreover, the models obtained were applied to analyse the effect of time after fire on fungal production. Mycorrhizal and edible fungal production after fire was classified into the lowest class, whereas saprotrophic and non-edible species followed a contrary trend. The classificatory models can be useful to optimise management and harvest of these increasingly appreciated non-timber forest resources. 相似文献
996.
Malinowski K Kearns CF Guirnalda PD Roegner V McKeever KH 《Journal of animal science》2004,82(12):3500-3507
Effects of longitudinal exercise training and acute intensive exercise (simulated race test) on immune function have not been reported in horses. Clenbuterol, a beta2-adrenergic agonist, is used to manage inflammatory airway disease in horses. This study investigated the interaction of 8 wk of exercise training with or without 12 wk of clenbuterol administration in horses. Twenty-three untrained standardbred mares (10 +/- 3 yr, Mean +/- SE) were used and divided into four experimental groups. Horses given clenbuterol plus exercise (CLENEX; n = 6) and clenbuterol alone (CLEN; n = 6) received 2.4 microg/kg BW of clenbuterol twice daily (in an average volume of 20 mL) on a schedule of 5 d on and 2 d off for 12 wk. The CLENEX group was also aerobically trained 3 d/wk. Mares given exercise alone (EX; n = 5) were aerobically trained for 3 d/wk, and the control group (CON; n = 6) remained sedentary. Both EX and CON horses were administered similar volumes (approximately 20 mL) of molasses twice daily. A simulated race test (SRT) resulted in an elevation in lymphocyte number postexercise (P < 0.05). There was no significant difference after acute exercise in either monocyte or granulocyte number. Acute exercise resulted in a decrease (P < 0.05) in the percentage of CD4+ and an increase (P < 0.05) in the percentage of CD8+ cells. The SRT resulted in a decreased lymphoproliferative response to pokeweed mitogen (P < 0.05). A SRT had no effect on antibody production in response to equine influenza vaccine. The EX group demonstrated greater cortisol concentrations at rest and at all other time points postexercise after completing the training regimen compared with CLENEX horses (P < 0.05). Preexercise (SRT) peripheral blood monocyte number was lower in CLENEX horses than in other treatment groups (P < 0.05). Clenbuterol and exercise training did not significantly affect post-SRT changes in leukocyte numbers. Exercise training resulted in a decrease (P < 0.05) in the percentage of CD8+ cells post-SRT compared with other groups, but the percentage of CD4+ cells was not altered by either clenbuterol or exercise conditioning. Lymphocyte proliferative response was not affected by clenbuterol or exercise treatment. Horses demonstrated responses to bouts of acute exercise as noted with other species, namely humans and rodents. 相似文献
997.
D. E. Jacobs M. A. Fisher J. G. Pilkington R. L. Jones V. C. Cracknell 《The Journal of small animal practice》1990,31(2):59-63
Trials were conducted to evaluate the anthelmintic effect of a combination of epsiprantel at a dose rate of 5-5 mg/kg bodyweight and pyrantel pamoate at 5 mg pyrantel base/kg against Toxocara canis in prenatally infected unweaned greyhound pups, Toxascaris leonina, Uncinaria stenocephala, Trichuris vulpis and Dipylidium caninum in naturally infected adolescent greyhounds and Ancylostoma caninum, U stenocephala. Taenia hydatigena and Taenia pisiformis in artificially infected laboratory beagles. The product was well accepted and produced no obvious side effects. Percentage efficacy values based on post mortem worm counts were: T hydatigena 100; T pisiformis 100; D caninum 100; adult T canis 84-0; adult T leonina 96-5; immature T leonina 99-8; U stenocephala 99-0 and 87-7; A caninum 92-7; and T vulpis 43-3. 相似文献
998.
Comesaña Losada M Leão JM Gago-Martínez A Rodríguez Vázquez JA Quilliam MA 《Journal of agricultural and food chemistry》1999,47(2):618-621
Further studies on mussel samples from Galicia, Spain, have revealed the presence of okadaic acid (OA), dinophysistoxin 2 (DTX2), and the fatty acid acyl esters of both of these toxins as the "DTX3" complex. Measurements were performed with an improved in situ method for the formation of 9-anthryldiazomethane (ADAM) derivatives followed by liquid chromatography with fluorescence detection. Base hydrolysis of DTX3 toxins gave free OA and DTX2, which were determined following ADAM derivatization. Results were confirmed by liquid chromatography/mass spectrometry analyses, and in most of the samples, free DTX2 was the most abundant toxin. However, the OA/DTX2 ratio in the DTX3 conjugated form was different, with OA being the most abundant in all cases. This difference could be due to different rates of metabolism of OA and DTX2 to the acyl esters or due to contamination of the shellfish by the two toxins at different points in time, resulting in less acyl ester formation for one toxin versus the other. The second possibility would be reasonable if two different source organisms were producing the toxins. 相似文献
999.
Physical, chemical, and serological characterization of rotavirus isolates from turkeys was done. Cesium chloride (CsCl)-gradient isopycnic centrifugation of infected cell cultures revealed the presence of rotavirus particles of three different densities. They were double-shelled, single-shelled, and core particles. The double-shelled particles had a buoyant density (in CsCl) of 1.34 g/cml3, and that of single-shelled particles in CsCl was 1.36 g/cm3. The buoyant density of core particles in CsCl was greater than 1.40 g/cm3. These rotavirus isolates were not inactivated by chloroform and were relatively stable at pH 3.0. Their replication was not affected by 5-bromo-2'-deoxyuridine. Avian rotaviruses were not completely inactivated by heat treatment of 56 C for 8 hr. All six avian rotavirus isolates examined were antigenically related to each other. However, there was no antigenic relationship between mammalian rotaviruses and the avian rotavirus isolates examined. 相似文献
1000.