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71.
Reproductive resilience: a paradigm shift in understanding spawner‐recruit systems in exploited marine fish 下载免费PDF全文
Susan Lowerre‐Barbieri Greg DeCelles Pierre Pepin Ignacio A Catalán Barbara Muhling Brad Erisman Steven X Cadrin Josep Alós Andres Ospina‐Alvarez Megan M Stachura Michael D Tringali Sarah Walters Burnsed Claire B Paris 《Fish and Fisheries》2017,18(2):285-312
A close relationship between adult abundance and stock productivity may not exist for many marine fish stocks, resulting in concern that the management goal of maximum sustainable yield is either inefficient or risky. Although reproductive success is tightly coupled with adult abundance and fecundity in many terrestrial animals, in exploited marine fish where and when fish spawn and consequent dispersal dynamics may have a greater impact. Here, we propose an eco‐evolutionary perspective, reproductive resilience, to understand connectivity and productivity in marine fish. Reproductive resilience is the capacity of a population to maintain the reproductive success needed to result in long‐term population stability despite disturbances. A stock's reproductive resilience is driven by the underlying traits in its spawner‐recruit system, selected for over evolutionary timescales, and the ecological context within which it is operating. Spawner‐recruit systems are species specific, have both density‐dependent and fitness feedback loops and are made up of fixed, behavioural and ecologically variable traits. They operate over multiple temporal, spatial and biological scales, with trait diversity affecting reproductive resilience at both the population and individual (i.e. portfolio) scales. Models of spawner‐recruit systems fall within three categories: (i) two‐dimensional models (i.e. spawner and recruit); (ii) process‐based biophysical dispersal models which integrate physical and environmental processes into understanding recruitment; and (iii) complex spatially explicit integrated life cycle models. We review these models and their underlying assumptions about reproductive success vs. our emerging mechanistic understanding. We conclude with practical guidelines for integrating reproductive resilience into assessments of population connectivity and stock productivity. 相似文献
72.
The transformations of eight herbicides (atrazine, simazine, terbutryn, pendimethalin, carbetamide, 2,4-D, metsulfuron-methyl and dimefuron) in soil after compost addition were monitored during long-term laboratory incubations. The herbicides were applied to soil, compost and soil-compost mixtures. Herbicide sorption, their kinetics of mineralisation and the extractability of residues were compared in the different treatments. Compost addition to soil generally decreased herbicide mineralisation and favoured the stabilisation of herbicide residues. A fraction of the stabilised residues remained extractable and potentially available. However, most of them were unextractable and formed bound residues. Sorption could be at the origin of a kinetically limited biodegradation, mainly for the most highly-sorbed herbicides (atrazine, simazine, terbutryn, pendimethalin and dimefuron). Compost addition had little effects on the less sorbed herbicides (carbetamide, 2,4-D and metsulfuron- methyl). © 1997 SCI. 相似文献
73.
Rmi Cousin Hugo Groult Chanez Manseur Romain Ferru-Clment Mario Gani Rachel Havret Claire Toucheteau Grgoire Prunier Batrice Colin Franck Morel Jean-Marie Piot Isabelle Lanneluc Kvin Baranger Thierry Maugard Ingrid Fruitier-Arnaudin 《Marine drugs》2021,19(10)
Sugar-based molecules such as heparins or natural heparan sulfate polysaccharides have been developed and widely studied for controlling heparanase (HPSE) enzymatic activity, a key player in extracellular matrix remodelling during cancer pathogenesis. However, non-enzymatic functions of HPSE have also been described in tumour mechanisms. Given their versatile properties, we hypothesized that sugar-based inhibitors may interfere with enzymatic but also non-enzymatic HPSE activities. In this work, we assessed the effects of an original marine λ-carrageenan derived oligosaccharide (λ-CO) we previously described, along with those of its native counterpart and heparins, on cell viability, proliferation, migration, and invasion of MDA-MB-231 breast cancer cells but also of sh-MDA-MB-231 cells, in which the expression of HPSE was selectively downregulated. We observed no cytotoxic and no anti-proliferative effects of our compounds but surprisingly λ-CO was the most efficient to reduce cell migration and invasion compared with heparins, and in a HPSE-dependent manner. We provided evidence that λ-CO tightly controlled a HPSE/MMP-14/MMP-2 axis, leading to reduced MMP-2 activity. Altogether, this study highlights λ-CO as a potent HPSE “modulator” capable of reducing not only the enzymatic activity of HPSE but also the functions controlled by the HPSE levels. 相似文献
74.
Effects of seasonal and environmental changes on aquaculture production in tropical Lake Volta,Ghana
Emmanuel T. D. Mensah Hederick R. Dankwa Lauridsen L. Torben Ruby Asmah Benjamin B. Campion Regina Edziyie 《Aquaculture International》2018,26(6):1387-1400
Globally, aquaculture production is faced with numerous challenges, notable among which is water quality. The study determined seasonal environmental changes in Lake Volta and its implications on cage production of Nile tilapia, Oreochromis niloticus in experimental and commercial farm (Sun Woo Farm) set-ups. For each set-up, three cages were used, each measuring 81 and 162.5 m3 for experimental and commercial, respectively. The cages were stocked with 22.5 g fingerlings at a rate of 40 and 80 m?3 in experimental and commercial cages, respectively, and fed commercial diet. The growth performance, yield, economics, and selected water quality parameters were monitored during the dry and wet seasons between November 2014 and July 2015. There were no differences in water quality parameters between dry and wet seasons (p?>?0.05). Water quality for both seasons remained within limits required for good Tilapia growth in both set-ups. There were minimal variations in growth characteristics between seasons which were not significant; however, final mean weight and yields were high in the dry seasons in both set-ups. The cost of feed and fingerling accounting for about 80% of total costs were the major components identified to affect cost of production. A higher profit index and returns on investment were observed in the dry season in both set-ups and was linked to higher survival rates in the season. Production of Nile tilapia in cages can be cultured throughout the year without any adverse effects as exhibited in similar production patterns in both experimental and commercial set-ups. 相似文献
75.
Claire Bouvard Isabelle Galy-Fauroux Fran?oise Grelac Wassila Carpentier Anna Lokajczyk Sophie Gandrille Sylvia Colliec-Jouault Anne-Marie Fischer Dominique Helley 《Marine drugs》2015,13(12):7446-7462
Low-molecular-weight fucoidan (LMWF) is a sulfated polysaccharide extracted from brown seaweed that presents antithrombotic and pro-angiogenic properties. However, its mechanism of action is not well-characterized. Here, we studied the effects of LMWF on cell signaling and whole genome expression in human umbilical vein endothelial cells and endothelial colony forming cells. We observed that LMWF and vascular endothelial growth factor had synergistic effects on cell signaling, and more interestingly that LMWF by itself, in the absence of other growth factors, was able to trigger the activation of the PI3K/AKT pathway, which plays a crucial role in angiogenesis and vasculogenesis. We also observed that the effects of LMWF on cell migration were PI3K/AKT-dependent and that LMWF modulated the expression of genes involved at different levels of the neovessel formation process, such as cell migration and cytoskeleton organization, cell mobilization and homing. This provides a better understanding of LMWF’s mechanism of action and confirms that it could be an interesting therapeutic approach for vascular repair. 相似文献
76.
77.
Claire Laugier Jackie TapprestNathalie Foucher BSc Corinne Sevin BSc 《Journal of Equine Veterinary Science》2009
The frequencies of neurologic diseases and various corresponding causes were analyzed in 4,319 Norman horses examined by autopsy between 1986 and 2006. Five hundred forty-three cases of nervous system disorders were detected, or a total prevalence of 12.6%. One hundred eighty-seven of the 543 horses (34.4%) exhibited lesions of a traumatic origin affecting the skull or the vertebral column at different levels. Their frequency was less in foals younger than 1 month of age and higher in horses aged 6 months to 2 years. Eighty-three cases of cervical vertebral compressive myelopathy (CVCM) (15.3%) were identified. Males and geldings were more often affected than females. CVCM was diagnosed mostly in animals aged 6 months to 2 years. Horses affected with lesions in the mid-cervical region (region C3–C5) were significantly younger than those exhibiting more caudal lesions (region C5–C7). Neonatal maladjustment syndrome was diagnosed in 62 foals younger than 3.5 days (4.8% of the causes of death between birth and 1 month) by using clinical or lesional criteria. The prevalence was higher in Thoroughbreds as well as in the miscellaneous breed category and less in French Standardbreds. Bacterial meningoencephalomyelitis and meningitis represented 9.6% of nervous system disorders (52 cases) and most often affected foals aged 1 to 6 months. The main bacteria identified were beta-hemolytic Streptococci , Escherichia coli, Listeria monocytogenes, Staphylococcus aureus, and Actinobacillus sp. The other causes diagnosed were, in decreasing order of frequency: grass sickness or equine dysautonomia (6.3% of neurologic diseases), hepatic encephalopathy syndrome (5.2%), septic vertebral arthritis or osteitis mainly caused by Rhodococcus equi (2.6%), congenital defects of the nervous system (2.4%), equine herpesvirus 1 myeloencephalopathy (2.2%), botulism (2.2%), malformations of the vertebral column other than CVCM (2%), and neighboring polyneuritis associated with guttural pouch mycosis (1.5%). 相似文献
78.
Laroucau K de Barbeyrac B Vorimore F Clerc M Bertin C Harkinezhad T Verminnen K Obeniche F Capek I Bébéar C Durand B Zanella G Vanrompay D Garin-Bastuji B Sachse K 《Veterinary microbiology》2009,135(1-2):82-89
Five severe cases of psittacosis in individuals associated with duck farms were notified in France between January and March 2006. Diagnostic examination included serology and/or molecular detection by PCR from respiratory samples. As a consequence, we investigated all duck flocks (n=11) that were housed in the three farms where human infections occurred. While serology by complement fixation test was negative for all samples, cloacal and/or tracheal chlamydial excretion was detected by PCR in all three units. Notably, one duck flock was tested strongly positive in 2 of the 3 affected farms, and Chlamydophila (C.) psittaci strains were isolated from cloacal and/or tracheal swab samples from both farms. Human samples and duck isolates exhibited the same PCR-RFLP restriction pattern, which appeared to be an intermediate between genotypes A and B. Analysis of ompA gene sequences and comparison to those of the type strains showed that the isolates could not be strictly assigned to any of the generally accepted genotypes of C. psittaci. Further analysis by MLVA of the PCR-positive human samples revealed two distinct patterns, which were related to previously isolated C. psittaci duck strains. 相似文献
79.
In Ireland, a new beef genetic index has been developed. Growth rate is expressed as expected progeny difference for carcass weight (EPDCWT) and is estimated on an across-breed basis. Cross-breeding of dairy cows with both Aberdeen Angus and Belgian Blue beef sires is widely practised. The objective of this study was to compare blood metabolites, slaughter traits and carcass composition of progeny from Holstein–Friesian dairy cows and Aberdeen Angus (AA), Belgian Blue (BB), Friesian (FR) and Holstein (HO) sires. The AA and BB sires were selected, within breed, to be of either high (H) or low (L) estimated genetic merit for carcass weight. A total of 170 male progeny from spring-calving cows and 42 sires (10 AA, 13 BB, 7 FR and 12 HO) were artificially reared indoors and managed together until the end of their second grazing season when they were assigned to either a Light (560 kg) or Heavy (620 kg) slaughter weight. Blood metabolite concentrations were measured six times throughout life and feed intake was recorded during the first and second winter. Carcass measurements and selected non-carcass components were recorded after slaughter and the right side of each carcass was dissected into lean, fat and bone. Differences in blood metabolite concentrations amongst genetic groups were negligible although there were some effects of the prevailing level of nutrition. M. longissimus area scaled for carcass weight was 0.220, 0.221, 0.260, 0.255, 0.212 and 0.208 (SE 0.004) cm2/kg for AAH, AAL, BBH, BBL, FR and HO, respectively. Carcass measurements scaled for carcass weight were greater for L, AA, HO and the dairy strains than for H, BB, FR and the beef breeds, respectively. There was no effect of estimated genetic merit for carcass weight on carcass composition. Statistically significant interactions between genetic merit and beef breed existed for some traits with the genetic merit effect largely evident for AA only. BB and the beef breeds had more lean, less fat and more high value lean in the carcass than AA and the dairy strains, respectively. It is concluded that genetic group had little effect on blood metabolite concentrations but there were some feeding level effects. Estimated genetic merit for carcass weight affected carcass weight, m. longissimus area and carcass measurements scaled for carcass weight but the effects were confined to AA. There were large effects of beef breed and dairy strain on carcass composition. 相似文献
80.