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101.
Intraguild predation of Geocoris punctipes on Eretmocerus eremicus and its influence on the control of the whitefly Trialeurodes vaporariorum 下载免费PDF全文
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José A. Vázquez Lorenzo Pastrana Carmen Pi?eiro José A. Teixeira Ricardo I. Pérez-Martín Isabel R. Amado 《Marine drugs》2015,13(10):6537-6549
This work investigates the production of hyaluronic acid (H) by Streptococcus equi subsp. zooepidemicus in complex media formulated with peptones obtained from Scyliorhinus canicula viscera by-products. Initially, in batch cultures, the greatest productions were achieved using commercial media (3.03 g/L) followed by peptones from alcalase hydrolyzed viscera (2.32 g/L) and peptones from non-hydrolyzed viscera (2.26 g/L). An increase of between 12% and 15% was found in subsequent fed-batch cultures performed on waste peptones. Such organic nitrogen sources were shown to be an excellent low-cost substrate for microbial H, saving more than 50% of the nutrient costs. 相似文献
105.
Leucocyte profile and growth rates as indicators of crowding stress in pejerrey fingerlings (Odontesthes bonariensis) 下载免费PDF全文
Yuri Dornelles Zebral Bruna Zafalon‐Silva Mabel Wiegand Mascarenhas Ricardo Berteaux Robaldo 《Aquaculture Research》2015,46(9):2270-2276
Crowding is one of the most common stressors found in intensive aquaculture, compromising growth rates and immune function. Plasmatic cortisol is a classic stress biomarker for fish, but its quantification is expensive and demands blood volumes that small individuals do not provide, constraining the usage of this technique to assess stress in fingerlings. The leucocyte profile is an alternative methodology to quantify stress with reduced costs and volumes of blood. Stress conditions promote neutrophilia and lymphocytopenia as response to elevated glucocorticoids levels. Considering the difficulties to assess stress imposed by intensive fish farming using measurement of glucocorticoid hormones, this study aimed to evaluate the stress‐induced changes in leucocyte profiles and growth rates imposed by crowding in fingerlings of Odontesthes bonariensis, a promising South‐American candidate for freshwater aquaculture. To meet these objectives, fingerlings (initial weight 0.05 ± 0.06 g and length 1.68 ± 0.13 cm) were reared for 45 days under three rearing densities (1, 5 and 10 fingerlings L?1). At the end of this period, fish were anaesthetized and euthanized to obtain the leucocyte profile, neutrophil:lymphocyte ratio (N:L) and growth rate. Increasing density promoted: significant reduction in growth (final length, weight and specific growth rate); neutrophilia and lymphocytopenia; and increased N:L ratio. Concluding, the tested rearing densities imposed distinct levels of stress characterized by different N:L ratio, demonstrating that the leucocyte profile is a reliable alternative to measure stress levels in O. bonariensis fingerlings and probably in other fish species. 相似文献
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Ricardo Marcos Marta Santos Fernanda Malhão Rui Pereira Ana Cristina Fernandes Luís Montenegro Paola Roccabianca 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2009,38(2):201-205
Abstract: A 4‐year‐old, domestic shorthair, female spayed cat was presented for decreased appetite and depression. Severe pancytopenia with erythrocyte autoagglutination was found. The cat was seronegative for feline immunodeficiency and leukemia viruses. Immune‐mediated hemolytic anemia was suspected but no response to treatment with a blood transfusion, enrofloxacin, and prednisone was observed. Blood and bone marrow smears obtained 11 days later contained Leishmania amastigotes in the cytoplasm of neutrophils and macrophages, respectively. Serologic and PCR testing of peripheral blood confirmed infection with Leishmania infantum. Despite treatment, the cat worsened clinically and was euthanized. At necropsy, visceral dissemination of the parasite was confirmed. The findings in this case indicate that visceral leishmaniasis should be considered as a differential diagnoses in cats with pancytopenia in areas endemic for Leishmania. In addition, amastigotes may be observed in peripheral blood neutrophils. 相似文献
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Ornithodoros erraticus is an argasid tick that can transmit severe diseases such as human relapsing fever and African swine fever. In southern Europe O. erraticus lives in close association with swine on free-range pig farms. Application of acaricides for the eradication of O. erraticus from pig farms is inefficient. This is the reason why we tried to develop an anti-O. erraticus vaccine as alternative method of control. Accordingly, we were prompted to investigate the protective possibilities of a midgut membrane extract from the parasite (GME) that has not been studied hitherto. Administration of the GME with Freund's adjuvants (FAs) to pigs and mice induced a protective response able to kill 80% of the immature forms of the parasite in the first 72 h post-feeding and to reduce the fecundity of females by more than 50%. The action of the vaccine is the result of damage to the midgut wall of the argasid, and, in mice, it has been shown that this damage is mediated by activation of the complement system. In pigs, the administration of GME with alum, instead of with FAs, reduced the degree of protection. The protective antigens of the GME were expressed by all the developmental stages examined and are probably proteins from the luminal membrane of midgut epithelial cells. These antigens were seen to be more abundant in recently fed parasites than in fasting specimens, suggesting that their expression is induced after blood ingestion. 相似文献
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Tessa Mazor C. Roland Pitcher Wayne Rochester Michel J. Kaiser Jan G. Hiddink Simon Jennings Ricardo Amoroso Robert A. McConnaughey Adriaan D. Rijnsdorp Ana M. Parma Petri Suuronen Jeremy Collie Marija Sciberras Lara Atkinson Deon Durholtz Jim R Ellis Stefan G. Bolam Michaela Schratzberger Elena Couce Jacqueline Eggleton Clement Garcia Paulus Kainge Sarah Paulus Johannes N. Kathena Mayya Gogina P. Daniël van Denderen Aimee A. Keller Beth H. Horness Ray Hilborn 《Fish and Fisheries》2021,22(1):72-86
Bottom trawl fishing is a controversial activity. It yields about a quarter of the world's wild seafood, but also has impacts on the marine environment. Recent advances have quantified and improved understanding of large‐scale impacts of trawling on the seabed. However, such information needs to be coupled with distributions of benthic invertebrates (benthos) to assess whether these populations are being sustained under current trawling regimes. This study collated data from 13 diverse regions of the globe spanning four continents. Within each region, we combined trawl intensity distributions and predicted abundance distributions of benthos groups with impact and recovery parameters for taxonomic classes in a risk assessment model to estimate benthos status. The exposure of 220 predicted benthos‐group distributions to trawling intensity (as swept area ratio) ranged between 0% and 210% (mean = 37%) of abundance. However, benthos status, an indicator of the depleted abundance under chronic trawling pressure as a proportion of untrawled state, ranged between 0.86 and 1 (mean = 0.99), with 78% of benthos groups > 0.95. Mean benthos status was lowest in regions of Europe and Africa, and for taxonomic classes Bivalvia and Gastropoda. Our results demonstrate that while spatial overlap studies can help infer general patterns of potential risk, actual risks cannot be evaluated without using an assessment model that incorporates trawl impact and recovery metrics. These quantitative outputs are essential for sustainability assessments, and together with reference points and thresholds, can help managers ensure use of the marine environment is sustainable under the ecosystem approach to management. 相似文献
110.
Ricardo Ayerza 《Industrial Crops and Products》2012,36(1):70-73
Moringa oleifera Lam. is a member of Moringaceae family which grows throughout most of the tropics, and is native to sub-Himalayan tracts of north west India, Pakistan, Bangladesh and Afghanistan. Moringa seed concentrates 35-45% oil which is considered a great natural cosmetic emollient almost total natural absence of color and odor, and high oleic acid concentration (>73%). To assess their production potential in the Arid Chaco, The Yungas Tropical Forest, Tropical Lowland Forest, and in the Sub-Humid Chaco Ecosystems of South America, a comparative trial was undertaken to determine their seed yield and oil content. Arid Chaco Ecosystem: significant (P < 0.05) difference in seed yields among years were found, with 176.17 and 481.25 kg/tree recorded for 1- and 2-year-old trees, respectively. Sub-Humid Chaco Ecosystems: the difference in seed yield and oil percentage between years was significant (P < 0.05). Comparison between years showed significantly (P < 0.05) higher seed yields, and significantly (P < 0.05) lower oil percentage for the two years old trees, than for the one year old trees. The oil/tree content was significantly (P < 0.05) higher for two years old trees than for one-year-old trees. Yungas Tropical Forest Ecosystem: seed oil percentage was significant (P < 0.05) higher in one-year-old trees than in seeds of two years old trees. Overall: over the tree years, oil percentage was significantly (P < 0.05) higher for seeds produced at the Arid Chaco than at the Sub-Humid Chaco. The seed/tree yields and the oil/tree content were no significantly (P < 0.05) different among the three ecosystems. However, when oil percentage per tree and seed yield/tree were combined trees from Sub-Humid Chaco and from Yungas Tropical Forest yielded significantly (P < 0.05) higher oil content compared to that from Arid Chaco trees. 相似文献