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1.
Exploring connectivity between spawning and nursery areas of Mullus barbatus (L., 1758) in the Mediterranean through a dispersal model 下载免费PDF全文
Connectivity between spawning and nursery areas plays a major role in determining the spatial structure of fish populations and the boundaries of stock units. Here, the potential effects of surface current on a red mullet population in the Central Mediterranean were simulated using a physical oceanographic model. Red mullet larvae were represented as Lagrangian drifters released in known spawning areas of the Strait of Sicily (SoS), which represents one of the most productive demersal fishing‐grounds of the Mediterranean. To consider the effect of inter‐annual variability of oceanographic patterns, numerical simulations were performed for the spawning seasons from 1999 to 2012. The main goal was to explore connectivity between population subunits, in terms of spawning and nursery areas, inhabiting the northern (Sicilian‐Maltese) and southern (African) continental shelves of the SoS. The numerical simulations revealed a certain degree of connectivity between the Sicilian–Maltese and the African sides of the SoS. Connectivity is present in both directions, but it is stronger from the Sicilian–Maltese spawning areas to the African nurseries owing to the marine circulation features of the region. However, because the majority of the larvae are transported to areas unsuitable for settlement or outside the SoS, the dispersal process is characterized by a strong loss of potential settlers born in the spawning areas. These results are in agreement with the low genetic heterogeneity reported for this species in the Mediterranean Sea and support the existence of a metapopulation structure of red mullet in the SoS and the adjacent areas. 相似文献
2.
Fernando LóPEZ-GATIUS Irene LóPEZ-HELGUERA Fabio DE RENSIS Irina GARCIA-ISPIERTO 《The Journal of reproduction and development》2015,61(5):465-471
This study compared the responses shown by lactating dairy cows to four different P4-based protocols for AI at estrus. Cows with no estrous signs 96 h after progesterone intravaginal device (PRID) removal were subjected to fixed-time AI (FTAI), and their data were also included in the study. In Experiment I, follicular/luteal and endometrial dynamics were assessed every 12 h from the beginning of treatment until AI. The estrous response was examined in Experiment II, and fertility was assessed in both experiments. The protocols consisted of a PRID fitted for five days, along with the administration of different combinations of gonadotropin releasing hormone (GnRH), equine chorionic gonadotropin and a single or double dose (24 h apart) of prostaglandin F2α. In Experiment I (40 cows), animals receiving GnRH at the start of treatment showed a significantly higher ovulation rate during the PRID insertion period while estrus was delayed. In Experiment II (351 cows),
according to the odds ratios, cows showing luteal activity at the time of treatment were less likely to show estrus than cows with no signs of luteal activity. Treatment affected the estrous response and the interval from PRID removal to estrus but did not affect conception rates 28–34 days post AI. Primiparous cows displayed a better estrous response than multiparous cows. Our findings reveal acceptable results of 5-day P4-based protocols for AI at estrus in high-producing dairy cows. Time from treatment to estrus emerged as a good guide for FTAI after a 5-day P4-based synchronization protocol. 相似文献
3.
4.
Fabio Soller Luke A. Roy D. Allen Davis 《Journal of the World Aquaculture Society》2019,50(1):186-203
Stearine fish oil (SFO) and palm oil (PO) have emerged as promising alternatives for the replacement of fish oil (FO) in aquafeeds. This study evaluated the replacement of FO with alternative oils in practical diets for Litopenaeus vannamei. In a clear brackish water study (14.1 g/L) utilizing shrimp (0.29 ± 0.02 g, initial weight), FO was replaced by SFO at inclusion ratios of 100:0, 75:25, 50:50, 25:75, and 0:100 (FO:SFO) and PO as 90% of FO. After 55 days, no significant differences (p < 0.05) in final weight, growth, or survival of shrimp were observed. A second trial (8 weeks) in low‐salinity water (2.1 g/L) with shrimp (0.92 ± 0.02 g, initial weight) evaluated diets with 100% FO, 100% SFO, 90% PO, 90% soybean oil (SO), or 90% flaxseed oil (FXO) as a replacement for FO and four commercially produced diets with 2% of FO, SO, PO, or FXO. One treatment received half rations of the commercial FO diet, and one treatment was based entirely on natural productivity. Results show that the fatty acid profiles of the tail muscle conformed to the lipids of the feed, and highly unsaturated fatty acids (HUFAs) were preserved. Following 8 weeks of culture, there were no significant differences in production performance. 相似文献
5.
Patrizia Spigaglia Fabrizio Barbanti Fabio Marocchi Marco Mastroleo Marco Baretta Patrizia Ferrante Emilia Caboni Simona Lucioli Marco Scortichini 《Plant pathology》2020,69(4):765-774
Since 2012, a new pathogenic syndrome has frequently been observed in many areas of kiwifruit cultivation in Italy. The main symptoms include an initial withering of the leaves followed by a total and sudden collapse of plants, mainly occurring during summer. The withered leaves fall and the main and secondary feeder roots appear rotten, sometimes showing a reddish-brown discoloration. The disease, that affects both the green and yellow-fleshed cultivars, has been called kiwifruit vine decline and is locally known as moria. The syndrome has been found consistently associated with soil waterlogging, which frequently occurs either after the traditional agronomical practice of irrigating orchards through surface irrigation or after very heavy rainfall. So far, the role played by bacteria in this syndrome has not been investigated. In the present study, Clostridium spp. were isolated from both rotten roots and soils obtained from Italian kiwifruit orchards affected by the syndrome, indicating for the first time that anaerobic bacteria are able to cause damage to woody crops. C. bifermentans and C. subterminale incited symptoms in kiwifruit in both in vivo and in vitro pathogenicity tests. Soil waterlogging seems to potentially favour colonization of kiwifruit roots by anaerobic bacteria, probably because saturation of the soil can facilitate proliferation and persistence of these bacteria during long periods of the vegetative growth of the crop. The occurrence of anaerobic bacteria does not exclude the possibility that other microorganisms can play additional/synergic role(s) in causing the kiwifruit vine decline. 相似文献
6.
Piovano M Chamy MC Garbarino JA Tita B Vitalone A Di Fabio A Nicoletti M 《Fitoterapia》2003,74(5):497-500
The crude methanolic root extract of Myoschilos oblongum exhibited a significant cytotoxic activity against PZ-HPV-7 human prostate cells. Furthermore, two esters of docosanol were isolated from the CH(2)Cl(2) extract. 相似文献
7.
Fabio Orlandi Tommaso Bonofiglio Luigia Ruga Carlo Sgromo Bruno Romano Marco Fornaciari 《Annals of Forest Science》2007,64(5):557-568
Phenological stages are the result of biorhythms and environmental factors, these last are probably the same ones that caused, during evolution, adjustments of the species to different climate. The present study was carried out in a Phenological Garden located in central Italy (Perugia, Umbria Region) which contains indicator species, common to all International Phenological Gardens. The aim of this study was to determine and analyse the average trends of development of eight plant species and their phenological adjustment to the Mediterranean environment, over a nine-year period (1997–2005). The results of the statistical analyses show a strong relationship between the temperature trends and vegetative seasonal evolutions interpreted by phenological data for all the species considered. Moreover, it was demonstrated that the plants studied may approach or close completely the timing gaps eventually created during the first phenological phases, adjusting thus the beginning of subsequent phenophases. 相似文献
8.
Julia Peixoto de Albuquerque Fabio Faria da Mota Irene von der Weid Lucy Seldin 《European Journal of Soil Biology》2006,42(4):200-207
Strains belonging to Paenibacillus durus isolated from the rhizosphere of various grasses and from bulk soil were previously divided into five phenotypic groups (A1–A5) based on the fermentation pattern of six carbohydrates (A1: sorbitol (+), A2: dulcitol and tagatose (+), A3: starch and glycogen (+), A4: starch, glycogen and d-arabitol (+) and A5: negative for these carbohydrates). This study aimed to assess whether plant types select for specific P. durus phenotypic groups. For that purpose, polymerase chain reaction-restriction fragment length polymorphism analysis of part of genes encoding 16S rRNA (ARDRA) and DNA gyrase subunit B (gyrB-RFLP) were used to produce genetic fingerprints. ARDRA and gyrB-RFLP data were clustered together to generate a dendrogram and two main clusters were observed. Cluster I showed a predominance of strains isolated from wheat, maize and sugarcane rhizospheres. Strains isolated from maize were distributed among the five patterns of carbohydrate metabolism, while strains isolated from sugarcane showed to be predominantly able to metabolize starch and glycogen. Neither sorbitol- nor arabitol-metabolizing strains were found in cluster II, which consisted of strains isolated from soil and from all plant species used. Our results suggest that the plants influenced the diversity of P. durus in their rhizospheres. 相似文献
9.
Mazzotti F Di Donna L Maiuolo L Napoli A Salerno R Sajjad A Sindona G 《Journal of agricultural and food chemistry》2008,56(1):63-67
A high-throughput mass spectrometric method is presented for the simultaneous detection of Sudan I, II, III, IV, and Para-Red azodyes in foodstuff. The method is based on the use of deuterium-labeled internal standards and atmospheric pressure chemical ionization (APCI) in a triple-quadrupole instrument. The gas-phase breakdown pattern of each labeled and unlabeled analogue displays the naphthoic moiety as a common fragment. The search for the parents of this common species (parent ion scans) allows, by flow injection and in a single run, the evaluation of the presence of each polluting species spiked in typical foodstuffs. A detailed assay of each azodye was performed by LC-APCI and isotope dilution method, through the multiple reaction monitoring approach, using deuterium-labeled internal standards. Sudan dyes can be quantified above the threshold of 10 ppb except for Sudan Para-Red, for which the limit of quantification was 20 ppb, likely due to the different ionization efficiency. 相似文献
10.
Fabio Donisete Pezzuto de Andrade Sonia Piacente Cosimo Pizza Wagner Vilegas 《Journal of agricultural and food chemistry》2002,50(2):255-261
The isolation of three new triterpene saponins 3beta-O-beta-D-glucopyranosyl-(1-->3)-alpha-L-2-O-acetylarabinopyranosylolean-12-en-28-oic acid 28-O-beta-D-glucopyranosyl ester (2), 3beta-O-beta-D-glucopyranosyl-(1-->2)-alpha-L-O-arabinopyranosylurs-12-en-28-oic acid (3), and 3beta-O-beta-D-glucopyranosyl-(1-->2)-beta-D-O-galactopyranosylurs-12-en-28-oic acid (4) together with five known saponins and one flavonoid glycoside from the aqueous infusion of Ilex amara (Vellozo) Loes. leaves is reported. All structures were elucidated by spectroscopic methods, including the concerted application of one-dimensional (1H, TOCSY, 13C, and 13C DEPT NMR) and two-dimensional NMR techniques (DQF-COSY, HSQC, and HMBC). 相似文献