Diet restriction induced autophagy: a lysosomal protective system against oxidative- and pollutant-stress and cell injury   总被引：1，自引：0，他引：1  

Moore MN 《Marine environmental research》2004,58(2-5):603-607

Nutrient deprivation or dietary restriction (DR) confers protection against ageing and stress in many animals and induced lysosomal autophagy is part of this mechanism. The effects of dietary restriction on the toxicity of copper and the polycyclic aromatic hydrocarbon phenanthrene have been investigated in the common marine mussel Mytilus edulis. The findings show that DR-induced autophagy facilitates the recovery of the digestive gland (i.e., molluscan liver analogue) from cell injury caused by both copper and phenanthrene. It is inferred that DR-induced autophagy and lysosomal proteolysis results in improved cellular "housekeeping" through the more efficient removal of oxidatively and pollutant damaged proteins (e.g., protein carbonyls, protein adducts, etc.) and that this contributes to stress resistance.  相似文献   

Linking foraging behavior and diet in a diving seabird          下载免费PDF全文

Sabrina Harris  Flavio Quintana  Javier Ciancio  Luciana Riccialdelli  Andrea Raya Rey 《Marine Ecology》2016,37(2):419-432

Foraging behavior and diet of breeding seabirds may be analysed simultaneously with the combined use of remote sensing devices and stable isotope analysis. Imperial shag, Phalacrocorax atriceps, breeding at Punta León colony, Argentina, were equipped with global positioning system (GPS) loggers to record foraging trips and blood samples were taken after removal of the devices in order to analyse their nitrogen and carbon stable isotope composition in whole blood and plasma. Whole blood was correlated to plasma isotopic composition for each individual (n = 35), linking diet in the short and medium term. Sexes did not differ in isotopic signatures. The maximum distance reached and the total number of dives that individuals made on two consecutive foraging trips were correlated to their plasma nitrogen isotopic signature. Individuals that went further from the colony and dived fewer times presented more positive signatures, indicative of benthic prey consumption (e.g. Raneya brasiliensis). Diet was predominantly benthic with some individuals incorporating pelagic prey (Engraulis anchoita) and even cephalopods (Octopus tehuelchus). Within breeding pairs (n = 9), different combinations of foraging and prey preferences were observed. Estimated trophic levels of these individuals were similar to those of the same species in other colonies further south along the Patagonian coast.  相似文献   

First report of gastroliths in the Early Cretaceous basal bird Jeholornis     

《Cretaceous Research》2018

Seeds preserved in association with the holotype of Jeholornis prima provided the first direct evidence of granivory in any Mesozoic bird. Although this long boney-tailed bird also displays several morphological indicators correlated with herbivory such as reduced dentition and a deep mandible, Jeholornis has not been previously reported to possess a gastric mill. However, this feature is commonly linked to herbivory in theropod dinosaurs and present in at least one sympatric ornithuromorph and the basal pygostylian Sapeornis, which also preserve direct evidence of granivory. Here we describe gastrolith masses preserved in five specimens of Jeholornis. The cluster of gizzard stones is nearly identical in each specimen, consisting of a tightly associated mass of proportionately small stones. Three previously undescribed specimens preserving seeds are also identified. Unlike in Sapeornis and a previously described ornithuromorph, no specimen of Jeholornis preserves both seeds and gastroliths. This may be due to the fact that, unlike in other Early Cretaceous birds, the seeds preserved in specimens of Jeholornis are found in the abdomen, suggesting that Jeholornis may have resembled extant ratites in lacking an esophageal crop. Consistent differences in the preservation and morphology of the gastrolith mass between Jeholornis and other early birds hint at subtle variations in alimentary function among basal lineages. Differences in ingested seed morphology among taxa in turn suggest these functional variations may be at least partially related to differences in diet.  相似文献   

The role of global dietary transitions for safeguarding biodiversity     

《Global Environmental Change》2019

Diets lower in meat could reduce agricultural expansion and intensification thereby reducing biodiversity impacts. However, land use requirements, associated with alternate diets, in biodiverse regions across different taxa are not fully understood. We use a spatially explicit global food and land system model to address this gap. We quantify land-use change in locations important for biodiversity across taxa and find diets low in animal products reduce agricultural expansion and intensity in regions with high biodiversity. Reducing ruminant meat consumption alone however was not sufficient to reduce fertiliser and irrigation application in biodiverse locations. The results differed according to taxa, emphasising that land-use change effects on biodiversity will be taxon specific. The links shown between global meat consumption and agricultural expansion and intensification in the biodiverse regions of the world indicates the potential to help safeguard biodiverse natural ecosystems through dietary change.  相似文献   

Feeding activity of adult roach (Rutilus rutilus (L.)), perch (Perca fluviatilis L.) and ruffe (Gymnocephalus cernuus (L.)) in eutrophic Lake Aydat (France)     

Jean-Louis Jamet 《Aquatic Sciences - Research Across Boundaries》1994,56(4):376-387

The feeding activity of adult roach (Rutilus rutilus), perch (Perca fluviatilis) and ruffe (Gymnocephalus cernuus) was studied over a one year cycle to show trophic relations between fish and the prey communities in eutrophic Lake Aydat.Daily consumption rates were referred to the stock of the different age classes of fish. Seven food compartments (phytoplankton, macrophytes, Cladocera, Copepoda, macroinvertebrates, fish and sediment) were used by the fish. The main prey compartment ofR. rutilus were macroinvertebrates (39.7%), sediment (29.0%), macrophytes (15.4%) and phytoplankton (14.9%). Little zooplankton was consumed (2.4%).P. fluviatilis fed mainly on macroinvertebrates and fish fry (both 41.8%) and some zooplankton (15.0%). ForG. cernuus, macroinvertebrates dominated in the diet (97.4%). During spring, Bacillariophyceae and macroinvertebrates represented the principal preys. During summer, insect larvae, phytoplankton and macrophytes were the principal components of the diet. At the end of summer, macrofauna was scare and fish tended to move to the pelagic zone feeding on plankton. In autumn, the prey spectrum was large. During winter, sediment was the most important item consumed, together with some macroinvertebrates. The impact of this fish community through consumption is highest on macroinvertebrates (40.7%), flora (27.7%) and sediment (28.4%). The predation of these three fish on zooplankton was low (1% per day of the zooplankton biomass) and restricted to periods when the other items were scarce. Interspecific competition is not excluded for macroinvertebrates.  相似文献   

中国饮食文化的区域分化和发展趋势   总被引：30，自引：2，他引：30  

陈传康 《地理学报》1994,49(3):226-235

现代地理学主要研究地球表层的“地体”与“地象”的区域特征和地域分异的时空发展规律。以食品和菜肴为“地体”，与餐饮有关的文化作为“地象”出发，本文通过饮食文化的地域分异、菜系的形成，中国四大菜系的比较研究，阐述中国饮食文化的区域特征和地域分化的时空发展规律，并预测其发展趋势。  相似文献   

Feeding of the Norwegian spring spawning herring Clupea harengus (Linne) at the different stages of its life cycle     

Irina Prokopchuk   《Deep Sea Research Part II: Topical Studies in Oceanography》2009,56(21-22):2044

The aim of the research was to investigate the diet of herring at different stages of its life cycle. For that purpose feeding of 0-group and immature herring in the Barents Sea, as well as of mature fish from the Norwegian Sea, was studied. 0-Group herring was sampled in the Barents Sea in August–September 2002–2005 during the international 0-group and trawl-acoustic survey of pelagic fish, as well as during the trawl-acoustic survey of demersal fish in November–December 2003–2004. Stomach samples of immature herring (1–3 years) were collected in late May and early of June 2001 and 2005 in the south-western part of the Barents Sea during the trawl-acoustic survey for young herring. Stomach samples of mature herring were collected in the Norwegian Sea in 1996, 1998, 1999, 2001, and 2002 in the course of the international trawl-acoustic survey of pelagic fish. Feeding intensity of herring of all age groups varied considerably between years and this was probably associated with availability and accessibility of their prey. The 0-group herring was found to have the most diverse diet, including 31 different taxa. In August–September, copepods, euphausiids, Cladocera, and larvae Bivalvia were most frequent in the diet of 0-group herring, but euphausiids and Calanus finmarchicus were the main prey taken. In November–December, euphausiids and tunicates were major prey groups. It was found that C. finmarchicus in the diet of 0-group herring was replaced by larval and adult euphausiids with increasing fish length. C. finmarchicus was the principal prey of immature herring and dominated in the diet of both small and large individuals and mainly older copepodites of C. finmarchicus were taken. Larval and adult euphausiids were found in stomachs of immature herring as well, but their share was not large. The importance of different prey for mature herring in the Norwegian Sea varied depending on the feeding area and length of the herring. On the whole C. finmarchicus and 0-group fish were the most important prey for mature herring diet, but fish prey were only important in a small sampling area. Hyperiids, euphausiids, tunicates, and pteropods were less important prey, and in 2002 herring actively consumed herring fry and redfish larvae.  相似文献   

Analysis of coprolites from the extinct mountain goat Myotragus balearicus     

Frido Welker  Elza Duijm  Kristiaan J. van der Gaag  Bas van Geel  Peter de Knijff  Jacqueline van Leeuwen  Dick Mol  Johannes van der Plicht  Niels Raes  Jelle Reumer  Barbara Gravendeel 《Quaternary Research》2014

Humans colonized the Balearic Islands 5–4 ka ago. They arrived in a uniquely adapted ecosystem with the Balearic mountain goat Myotragus balearicus (Bovidae, Antilopinae, Caprini) as the only large mammal. This mammal went extinct rapidly after human arrival. Several hypotheses have been proposed to explain the extinction of M. balearicus. For the present study ancient DNA analysis (Sanger sequencing, Roche-454, Ion Torrent), and pollen and macrofossil analyses were performed on preserved coprolites from M. balearicus, providing information on its diet and paleo-environment. The information retrieved shows that M. balearicus was heavily dependent on the Balearic box species Buxus balearica during at least part of the year, and that it was most probably a browser. Hindcast ecological niche modelling of B. balearica shows that local distribution of this plant species was affected by climate changes. This suggests that the extinction of M. balearicus can be related to the decline and regional extinction of a plant species that formed a major component of its diet. The vegetation change is thought to be caused by increased aridity occurring throughout the Mediterranean. Previous hypotheses relating the extinction of M. balearicus directly to the arrival of humans on the islands must therefore be adjusted.  相似文献   

基于脂肪酸标记的长江口海区浮游动物常见种食性分析   总被引：5，自引：0，他引：5  

金鑫  李超伦  孙松  刘梦坛 《海洋与湖沼》2012,43(6):1083-1090

脂肪酸不仅是浮游动物的重要组分,也被作为生物标记来指示动物的食物组成及其之间的营养关系。本文运用脂肪酸标记法对长江口附近海区6个浮游动物常见种的食性进行了分析。研究结果表明,中华哲水蚤(Calanus sinicus)雌体和桡足幼体都表现出明显的植食性。但雌体中16:1ω7的含量要明显高于18:4ω3,表明雌体对硅藻的摄食较多;桡足幼体的18:4ω3要高于雌体,说明桡足幼体对甲藻的摄食较多。磷虾(Euphausia spp.)的多不饱和脂肪酸(PUFA)和ω3系列脂肪酸的含量很高,说明其作为饵料可以给摄食者提供较多的脂类营养物质。中华哲水蚤和磷虾较低的22:6ω3/20:5ω3比值说明他们的营养地位较低。箭虫(Sagitta spp.)的20:1和22:1脂肪酸含量很高,指示了其对植食性桡足类的摄食。蝶水母(Ocyropsis crystallina)、瓜水母(Bero cucumis)和四叶小舌水母(Liriopetetraphylla)的20:1+22:1脂肪酸所占比例较高,指示了其对植食性桡足类的摄食,但是水母类的总脂肪酸含量都很低。几种水母和箭虫的22:6ω3的含量要明显高于20:5ω3的含量,说明它们在浮游食物网中具有较高的营养地位。  相似文献   

Coastal habitat degradation and green sea turtle diets in Southeastern Brazil     

Santos RG  Martins AS  Farias Jda N  Horta PA  Pinheiro HT  Torezani E  Baptistotte C  Seminoff JA  Balazs GH  Work TM 《Marine pollution bulletin》2011,62(6):1297-1302

To show the influence of coastal habitat degradation on the availability of food for green turtles (Chelonia mydas), we assessed the dietary preferences and macroalgae community at a feeding area in a highly urbanized region. The area showed low species richness and was classified as degraded. We examined stomach contents of 15 dead stranded turtles (CCL = 44.0 cm (SD 6.7 cm)). The diet was composed primarily of green algae Ulva spp. (83.6%). In contrast, the macroalgae community was dominated by the green alga Caulerpa mexicana. We found a selection for red algae, seagrass and Ulva spp., and avoidance for C. mexicana and brown alga Dictyopteris delicatula. The low diversity of available food items, possibly a result of environmental degradation, likely contributed to the low dietary diversity. The nutritional implications of this restricted diet are unclear.  相似文献