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排序方式: 共有142条查询结果,搜索用时 15 毫秒
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113.
Andrea Pecora María Sol Pérez Aguirreburualde Agustín Ostachuk Alejandra Aguirreburualde Maria Rosa Leunda Anselmo Odeon Sebastián Chiavenna Diego Bochoeyer Marcelo Spitteler Jorge L. Filippi Maria J. Dus Santos Susana M. Levy Andrés Wigdorovitz 《Veterinary research communications》2016,40(3-4):149-149
114.
Ploeger HW Borgsteede FH Sol J Mirck MH Huyben MW Kooyman FN Eysker M 《Veterinary parasitology》2000,90(4):247-304
A cross-sectional survey was carried out on 86 farms randomly distributed in The Netherlands. After housing following the first and the second grazing season (FGS and SGS) serum samples were collected to determine IgG levels against Cooperia oncophora and Dictyocaulus viviparus, and the pepsinogen content. A questionnaire was used to inquire on grazing management practices and the use of anthelmintic drugs. On 80.7 and 60.2% of the farms FGS and SGS animals, respectively, were treated at least once with an anthelmintic drug. The percentage for the SGS animals indicates that the use of anthelmintic drugs in those animals has increased enormously over the last 10–15 years. Generally, parasitic nematode control in the FGS is good on most farms, but it can be characterised as being overprotective. There is a tendency that if anthelmintic drugs are used in the FGS they also are used more often in the SGS. On 12 farms (14%), no anthelmintic drugs were given in the FGS and the SGS. These farms did not differ from the others with respect to management practices in any obvious way. The serological results were in general very low, indicating low levels of exposure to gastrointestinal nematode infection in both FGS and SGS animals. This was not surprising in view of the good to high level of nematode control practices reported by the farmers. Although not statistically significant, a consistent result was that serological results for the SGS animals were more often positive or on average higher on those farms where FGS parasite control tended to be excessive. For D. viviparus, a prevalence rate of 41% positive farms was found. Following comparison with previous data, it is speculated that lungworm (sero-)prevalence in replacement stock may be declining as a result of continuing high levels of parasite control in replacement stock. It is concluded that the results confirm previous surveys, lending support to the conclusion that parasitic nematode control on Dutch dairy farms, certainly in FGS calves, is good but tends to be overprotective. 相似文献
115.
A. Boglino M.J. Darias A. Estévez K.B. Andree C. Sarasquete J.B. Ortiz‐Delgado M. Solé E. Gisbert 《Aquaculture Nutrition》2014,20(6):692-711
Fish tissues, particularly rich in n‐3 PUFA, are prone to lipid peroxidation that can damage cellular membranes, cause severe lesions and subsequently incidences of disease and mortality. However, fish possess antioxidant defences, such as vitamin E (VE) and antioxidant enzymes, to protect them against oxidative damage. This study investigated the effects of an increasing gradient of oxidized dietary lipid on the survival, growth performance, skeletogenesis and antioxidant defensive processes occurring in Senegalese sole (Solea senegalensis) larvae. Four groups of fish were fed live prey enriched with experimental emulsions containing an increasing gradient of oxidized oil: non‐oxidized, NO+VE, 34.5 nmol MDA g?1 w.w.; mildly oxidized, MO+VE, 43.1 nmol MDA g?1 w.w.; highly oxidized, HO+VE, 63.3 nmol MDA g?1 w.w. and highly oxidized without VE, HO‐VE, 78.8 nmol MDA g?1 w.w. The oxidation levels increased in enriched rotifers following the oxidation gradient of the emulsions, but were not affected in enriched Artemia metanauplii. The oxidation status of Senegalese sole larvae increased during development, but this was not related to the dietary treatments. The increasing dietary oxidation levels did not affect the fatty acid profile, survival, growth performance and metamorphosis processes of sole larvae. Senegalese sole seem to activate antioxidant defence mechanisms in response to the increasing amounts of dietary peroxidized lipids, in a manner efficiently enough to prevent detection of any alterations of these physiological processes. Antioxidant systems and detoxification mechanisms appeared to occur through the consumption of dietary α‐tocopherol, the activation of the antioxidant enzymes (catalase, superoxide dismutase, glutathione S‐transferase, glutathione reductase) and the retention of oxidized fat in the intestinal enterocytes for detoxification prior to their utilization. However, fish fed the highest oxidized diet presented a reduction in bone mineralization, but lower incidence of deformities in the vertebral and caudal regions than fish fed the other diets. This study exemplifies the importance of rearing Senegalese sole larvae on non‐oxidized diets during the early larval development to avoid detrimental consequences in older fish, most notably in the process of skeletogenesis. 相似文献
116.
Adults from spider crab, Maja brachydactyla, Balss, 1922 were kept in captivity for up to 2 years. Haemolymph of ten females was extracted monthly for monitoring several metabolites and the presence of Vibrionacea bacteria. A neurotoxic marker and hepatic metabolic and digestive enzyme capacities were contrasted between wild specimens and those reared in captivity. As a result, no differences were observed in hepatosomatic index (HSI) between males and females, but captive animals presented lower HSI than the wild ones. After 2 years of confinement, no changes in quantities of haemolymph microflora and metabolites were observed and this was considered indicative of adaptation of the broodstock to confinement. Spider crab also showed a large plasticity in their hepatopancreatic digestive capabilities suggested by the adaptation to the food supplied in captivity. Moreover, captivity conditions did not seem to negatively alter their antioxidant defences, xenobiotic capacity or neuromuscular activity, as no enhanced oxidative stress damage was shown in either males or females. These results indicate that although the confinement conditions used in this study do not mimic those from the wild, they could be considered as adequate for rearing M. brachydactyla in captivity, at least with regard to the set of parameters assessed. 相似文献
117.
José-Arturo Solórzano Jeremie Gilles Oscar Bravo Cristina Vargas Yannery Gomez-Bonilla Georgina V. Bingham David B. Taylor 《Journal of insect science (Online)》2015,15(1)
Pineapple production in Costa Rica increased nearly 300-fold during the last 30 yr, and >40,000 hectares of land are currently dedicated to this crop. At the end of the pineapple cropping cycle, plants are chopped and residues incorporated into the soil in preparation for replanting. Associated with increased pineapple production has been a large increase in stable fly, Stomoxys calcitrans (L.), populations. Stable flies are attracted to, and oviposit in, the decomposing, chopped pineapple residues. In conjunction with chemical control of developing larvae, adult trapping is an important control strategy. In this study, four blue-black fabric traps, Nzi, Vavoua, Model H, and Ngu, were compared with a white sticky trap currently used for stable fly control in Costa Rica. Overall, the white sticky trap caught the highest number of stable flies, followed by the Nzi, Vavoua, Model H, and Ngu. Collections on the white sticky trap increased 16 d after residues were chopped; coinciding with the expected emergence of flies developing in the pineapple residues. During this same time period, collections in the blue-black fabric traps decreased. Sex ratio decreased from >7:1 (females:males) 3–7 d after chopping to 1:1 at 24–28 d. White sticky, Nzi and Vavoua traps collected similar numbers of colonizing flies 3–7 d after residues were chopped. However, white sticky traps collected more flies once emergence from the pineapple residues began. Although white sticky traps collected more flies than fabric traps, they remain labor intensive and environmentally unsound because of their disposable and nonbiodegradable nature. 相似文献
118.
Thomas F Jamin E Wietzerbin K Guérin R Lees M Morvan E Billault I Derrien S Moreno Rojas JM Serra F Guillou C Aursand M McEvoy L Prael A Robins RJ 《Journal of agricultural and food chemistry》2008,56(3):989-997
Variability within the stable isotope ratios in various lipidic fractions and the fatty acid composition of muscle oil has been analyzed for a large sample (171 fish) of wild and farmed Atlantic salmon ( Salmo salar) from 32 origins within Europe, North America, and Tasmania. Sampling was extended over all seasons in 2 consecutive years and included fish raised by different practices, in order to maximize the range of variation present. It is shown that two readily measured parameters, delta 15N measured on choline and delta18 O measured on total oil, can be successfully used to discriminate between fish of authentic wild and farmed origin. However, the certainty of identification of mislabeling in market-derived fish is strengthened by including the percentage of linoleic acid C18:2n-6 in the lipidic fraction. Thus, several apparent misidentifications were found. The combination of these three analytical parameters and the size of the database generated makes the method practical for implementation in official laboratories as a tool of labeling verification. 相似文献
119.
We report the preparation of polybenzoxazole (PBO) fiber from polyhydroxyamide (PHA) precursor fiber which is free from strong acid such as polyphosphoric acid. We prepared the PHA fibers with different spin-draw ratios (SDRs) using a wet-spinning method and the PBO fibers with an SDR of 3.5 (SDR-3.5 PBO fibers) were prepared by various heat-treatment temperatures, and investigated their morphology, crystalline structure, and mechanical properties. The simultaneous thermogravimetric analysis-mass spectrometry (STA-MS) and field-emission scanning electron microscopy (FE-SEM) results confirmed that the diameter of the SDR-3.5 PBO fiber was much smaller than that of the SDR-3.5 PHA fiber, due to the release of water during the thermal cyclization reaction which forms the PBO structure. The wide-angle Xray diffraction (WAXD) pattern of the SDR-3.5 PBO fiber heat-treated at 350 °C (SDR-3.5 PBO 350 fiber) showed two peaks, at 2θ=14.83 ° and 24.38 °, and the diffraction angles dropped with increasing heat-treatment temperature. In addition, the initial modulus and tensile strength of the SDR-3.5 PBO fiber heat-treated at 550 °C (SDR-3.5 PBO 550 fiber) were found to be 19.1 GPa and 449.2 MPa, which were much higher than those of the SDR-3.5 PHA fiber, 9.3 GPa and 227.0 MPa, respectively. 相似文献
120.