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61.
Jean‐Baptiste Ledoux Silvia Frias‐Vidal Ignasi Montero‐Serra Agostinho Antunes Clara Casado Bueno Sergi Civit Paula Lopez‐Sendino Cristina Linares Joaquim Garrabou 《水产资源保护:海洋与淡水生态系统》2020,30(6):1149-1159
- Understanding the interactions among demographic parameters, mating system and population dynamics is key to predict the response of populations to global change. The Mediterranean red coral is a precious octocoral suffering from population decline due to overfishing and warming‐driven mass mortality events.
- While the demographic consequences of these two pressures are well characterized, little is known regarding their impact on population dynamics and evolution of red coral populations. The main objective of this study was to fill this gap focusing more particularly on mating pattern and genetic drift.
- Combining sibship and progeny arrays analyses, a genetic characterization of the red coral mating system was conducted. In addition, a synchronic approach was developed comparing mating patterns in two populations with contrasting demographic patterns: a pristine‐like population and a declining population.
- The results show that polyandry is likely to be the norm in red coral. The similar patterns of genetic diversity between adults and larvae combined with the lack of differential reproductive success among putative fathers did not support significant sweepstakes effects during larval production. While instantaneous biparental inbreeding was detected, no long‐term inbreeding was observed even in the declining population. Mating patterns and effective population sizes in the two populations were not statistically different. Nevertheless, a trend towards a slightly higher inbreeding and a lower number of breeders was observed in the declining population.
- Accordingly, we hypothesized that an increase in male gamete dispersal may buffer the increase of genetic drift expected in the declining population. This feedback between demographic decline and reproductive pattern may potentially take part in the long‐term persistence of red coral populations. However, the negative trend reported in the declining population unambiguously supports the need to maintain high densities of reproductive colonies to the functioning of red coral populations.
62.
Renata Squarzoni Eduardo Perlmann Andrea Antunes Liliane Milanelo Paulo Srgio De Moraes Barros 《Veterinary ophthalmology》2010,13(Z1):86-90
Objective To report the biometric values and ultrasonographic aspects of the normal eye of the Striped owl (Rhinoptynx clamator). Sample population Twenty‐seven healthy, free‐living, adult Striped owls from the Ecological Park of Tiete Veterinary Ambulatory (Sao Paulo, Brazil). Procedures Both eyes of all owls underwent B‐mode ultrasonographic examination and biometry was performed for lens axial length (WL), depth of the anterior (AC) and vitreous (VC) chambers, axial length of the globe (LB) and the pecten oculi (LP) of both eyes, using a 12 MHz probe. The owls were manually restrained without sedation and the eyes were topically anesthetized. Results Biometric and statistical findings were as follows: in the left eye, the means and standard deviations were: LB = 23.76 ± 0.92 mm, WL = 7.79 ± 0.27 mm, AC = 4.27 ± 0.47 mm, VC = 11.36 ± 0.29 mm and LP = 5.69 ± 0.50 mm; in the right eye, the values were: LB = 24.25 ± 0.79 mm, WL = 8.03 ± 0.40 mm, AC = 4.56 ± 0.52 mm, VC = 11.40 ± 0.25 mm, and LP = 5.68 ± 0.41 mm. No significant differences were found between left and right eyes measurements of LB, WL, AC, VC, and LP dimensions. Conclusions Ocular ultrasound aspects and biometric values of the Striped owl are reported. The study’s results provide means for various ocular measurements. The ultrasound is an easy and safe exam to be performed in the Striped owl’s eyes. 相似文献
63.
A Marques P Santos G Antunes A Chaveiro F Moreira da Silva 《Reproduction in domestic animals》2010,45(1):81-85
The objectives of this work are to determine if exogenous supplementation with α-tocopherol increases the in vitro fertilization (IVF) rate of bovine oocytes and improves viability of selected spermatozoa after 'swim-up'. The percentage of fertilized oocytes was significantly but negatively correlated ( r = −0.941, p < 0.01) with the concentration of α-tocopherol. The control resulted in 95% of fertilized oocytes, which decreased as follows: 25 μM α-tocopherol (α25) 86%, 50 μM α-tocopherol (α50) 74%, 100 μM α-tocopherol (α100) 66% and 200 μM α-tocopherol (α200) 56%. Relatively to sperm viability after 'swim-up' with α-tocopherol supplementation, this antioxidant proved to have a beneficial effect as its concentration increased up to α50, decreasing for the concentrations of α100 and α200. Control resulted in 83% of live cells and 16% of dead cells; α25 resulted in 88% of live cells and 12% of dead cells; α50 resulted in 91% of live cells and 9% of dead cells; α100 resulted in 67% of live cells and 33% of dead cells; and finally α200 resulted in 57% of live cells and 42% of dead cells. In summary, the present study allows to conclude that, in our conditions, supplementation with the antioxidant α-tocopherol in IVF of bovine oocytes has a detrimental effect on fertilization rates. Nevertheless, exogenous supplementation with α-tocopherol at a concentration of 50 mM in the sperm-TALP media during the 'swim-up' technique has a significant beneficial effect on the selected spermatozoa viability. 相似文献
64.
Large reservoirs as ecological barriers to downstream movements of Neotropical migratory fish
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Most large rivers in South America are fragmented by large dams, and a common management strategy to mitigate impacts has been construction of fish passes. Recent studies, however, indicate that downstream passage of adults and young fish is nil or minimal. Better understanding of this phenomenon is needed if fishways are to provide any tangible conservation value in South America. We propose, in this article, that large reservoirs impose a different kind of barrier to migrating fish: impoundments create a diffuse gradient of hydraulic/limnological conditions that affects fish behaviour and functions as an extensive environmental filter that discourages downstream movements. To develop this idea, we characterize the barriers created by dams and reservoirs by describing their distinct nature, the effects on fish migration and potential solutions. We show, for example, that dams generally prevent upstream movements, whereas reservoirs impede mainly downstream movements. In this context, we explain how fish passes, in some instances, can partially mitigate fragmentation caused by dams, but there is no technical solution to solve the barrier effect of reservoirs. In addition, we present a body of empirical evidence that supports the theory that large reservoirs are important barriers to fish migration in South America, we offer an overview of the size of reservoirs to show that impoundments typically have large dimensions, and we discuss the significance of this theory for other regions. Based on current and proposed river regulation scenarios, we conclude that conservation of Neotropical migratory fish will be much more complicated than previously believed. 相似文献
65.
Brazilian wetlands: their definition,delineation, and classification for research,sustainable management,and protection 总被引:1,自引:0,他引:1
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W. J. Junk M. T. F. Piedade R. Lourival F. Wittmann P. Kandus L. D. Lacerda R. L. Bozelli F. A. Esteves C. Nunes da Cunha L. Maltchik J. Schöngart Y. Schaeffer‐Novelli A. A. Agostinho 《水产资源保护:海洋与淡水生态系统》2014,24(1):5-22
- 相似文献
66.
Ribeiro LM Ferreira DA Brás S Gonzalo-Orden JM Antunes LM 《Veterinary anaesthesia and analgesia》2012,39(1):21-28
ObjectiveTo evaluate if the cerebral state index (CSI), measured by a Cerebral State Monitor (CSM), can predict depth of anaesthesia as assessed clinically or by estimated propofol plasma concentrations.Study designProspective clinical study.AnimalsFourteen mixed breed dogs, weighing 24.5 ± 4.7 kg, scheduled to undergo neutering procedures.MethodsDogs were premedicated with 0.05 mg kg?1 acepromazine intramuscularly. The CSM and cardiovascular monitoring equipment were attached. Anaesthesia was induced with propofol using a target controlled infusion (TCI) to varying plasma propofol targets (PropCp). Following endotracheal intubation the dogs were ventilated with oxygen. Anaesthetic maintenance was with propofol by TCI. A PropCp of 3 μg dL?1 was set initially, then PropCps were increased in 1 μg dL?1 steps to 7, 9 and then 11 μg dL?1. Each PropCp was held constant for a 5 minute period, at the end of which depth of anaesthesia was classified using a previously evaluated scale of ‘planes’ based on palpebral and corneal reflexes and eye position. Cerebral state index (CSI), burst suppression (BSR) and electromyogram were measured at these time points. The prediction probability (PK) of these variables, or of the PropCp in predicting depth of anaesthesia was calculated.ResultsThe PKs for predicting anaesthetic planes were 0.74, 0.91, 0.76 and 0.78 for CSI, BSR, EMG and PropCp, respectively. The PKs for PropCp to predict CSI, BSR and EMG were 0.65, 0.71 and 0.65 respectively.Conclusion and clinical relevance The Cerebral State Monitor was able to detect very deep planes of anaesthesia when BSR occurs, but was not able to distinguish between the intermediate anaesthetic planes likely to be used in clinical anaesthesia. 相似文献
67.
Marcus V. Vieira Natalie Olifiers Ana C. Delciellos Vanina Z. Antunes Luis R. Bernardo Rui Cerqueira 《Biological conservation》2009,142(6):1191-1200
The remaining Atlantic Forest fragments are structurally isolated by a matrix of pastures, plantations, or urban areas, and most remnants are small (<100 ha). Island biogeography theory has been used to predict the effects of such fragmentation in the remaining fragments, but human activities and land use around fragments may be equally important. A related question is which aspects of land use have a strong effect on biodiversity. We compare the relative importance of fragment size and isolation vs. land use around fragments as determinants of composition and richness of small mammals in Atlantic Forest fragments. We also compare two aspects of land use around fragments, economic activity (peri-urban, agriculture, cattle), and property ownership (peri-urban, low income rural producers, affluent rural producers). Small mammals were surveyed in 21 fragments varying from 12 to 250 ha, and in two sites of continuous forest in the Macacu River watershed, State of Rio de Janeiro, Brazil, from 1999 to 2007. The effects of land use, fragment size and isolation were formulated as eleven candidate models, compared by Akaike Information Criteria. In the models selected, species composition was associated more strongly with fragment size, followed by isolation, with a smaller effect of property ownership. Species richness was determined mostly by fragment isolation, but also by a negative effect of agriculture when it was the dominant economic activity. Regardless of the critics to island biogeography theory, fragment isolation and size were by far the most important determinants of species composition. Economic activity and property ownership allowed the detection of subtle but important effects of land use on species composition and richness. 相似文献
68.
Pre-inoculation of seedlings with commercial, typically non-indigenous, AMF inoculants is common practice in horticultural and land reclamation industries. How these practices influence AMF community composition in pre-inoculated seedlings after they are planted in soil containing a resident AMF community is almost completely unknown. However, there may be important implications regarding success of horticultural practices, as well as unexpected ecological consequences. In this study we exposed Leucanthemum vulgare seedlings to five different AMF treatments (pre-inoculation with a representative of Glomus group A and Glomus group B, one of two Gigaspora spp., or no AMF) prior to exposure to a whole-soil, mixed-AMF community inoculum. After a growth period of 75 additional for 28 days, AMF community composition within the roots was analyzed using an approach combining LSU rDNA sequencing and T-RFLP analysis. Our results indicate that the AMF communities that assemble within roots were strongly influenced by AMF pre-inoculant identity. Pre-inoculation with either Glomus spp., unlike what was found for Gigaspora, greatly restricted numbers of other AMF ribotypes able to subsequently colonize roots after exposure to our Glomeraceae-dominated field soil; this suggested that phylogenetic relatedness and life history strategies may play a role in AMF community assembly. Our results further revealed concurrent changes in AMF community functions, as indicated by differences in plant biomass and foliar nutrients. These results serve to highlight the importance of considering life history differences when designing AMF inoculants and may have important implications regarding the introduction of non-indigenous AMF. 相似文献
69.
Isabela Hernandes Olivia Diulen Costa Brito Michelly Ragazzi Cardoso Julio Cesar Antunes Ferreira Heriksen Higashi Puerari Claudia Regina Dias-Arieira 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2017,67(7):660-664
Nematodes are among the main limiting factors of the vegetables productivity, especially due to management restriction this crop to obtain an efficient control of pathogen. Resistance induction using acibenzolar-S-methyl (ASM) has presented promising results in the management of diseases, but to plant-parasitic nematodes the time required to activate latent defense mechanisms is a limiting factor, which can be prevented with the treatment of seedlings in trays. Thus, the present study aimed to assess different times of ASM application to Meloidogyne javanica control in lettuce. Lettuce seedlings were produced in trays, transplanted to pots 25 days after germination and inoculated with 2000 eggs of the nematode. The seedlings were pulverized on shoots with ASM 10 or 5 days before of transplant (DBT), on the day of transplant (DT), 5 or 10 days after transplant (5 or 10 DAT), 10 DBT?+?DT and 10 DBT?+?5 DAT. The untreated plants formed the control group. Fifty days later, these plants were collected and evaluated the nematological and vegetative parameters. The treatments promoted a decrease in M. javanica population higher than 60% when applied until 5 DAT and generally did not interfere with the vegetative parameters of lettuce, and ASM can be adopted as an alternative for the root-knot nematodes management. 相似文献
70.
Andréia Peiter Tanna E. R. Fiuza Roberto de Matos Augusto Celso Antunes Sandra Regina Masetto Antunes Cleber A. Lindino 《Water, air, and soil pollution》2017,228(3):114
To meet demand for processes that minimize the environmental impact generated by waste, efficient systems that degrade such substances and use them as an alternative source for renewable energy generation are increasingly becoming needed. Increased food production to meet the needs of the world’s increasing population has encouraged the use of agrochemicals in order to ensure productivity in crops. However, excessive use of pesticides has caused contamination of natural systems and, therefore, of living beings. In this context, this work presents an alternative plan for an integrated system that simultaneously remediates contaminated environments and generates electricity using a Cu/CuO electrode as a photocatalyst. The materials were prepared from reagents and accessible metals, which reduced costs and contributed to a clean process, without using organic additives. The results showed that the generation of current in an area 6.9 cm2 was 193.37 μA for potassium hydrogen phthalate degradation. The Aminol 806® and Connect® pesticides were degraded by 54.46 and 21.02%, respectively, after 90 min in the system, under ultraviolet radiation. The results showed that, at pH 2.0, the generation of current was 2493.2 mA (36.165 mA m?2) for Aminol 806® and 7.894 mA (0.114 mA m?2) for Connect®. The degradation of organic contaminants and simultaneous power generation of energy in the integrated system provides a self-sustaining form of environmental remediation and energy recovery, and its use is possible on a large scale. 相似文献