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101.
Biotic invasions have a reputation for unpredictable behavior. Here, we report how slight changes in human activity responsible for the introduction and range expansion of a non-native mollusk have led to detectable differences in the genetics of the invasion. Cyclope neritea is a non-predatory gastropod introduced to 2 areas of the European Atlantic: the northwest Iberian Peninsula (NWIP) and the French Atlantic coast (FAC). Shellfish seabed farming is intense in both areas but focuses on different commercial species. Using mitochondrial gene sequences, the lower genetic diversity recorded along the NWIP suggests a more homogeneous range of source populations than in the FAC. Unlike FAC, genetic diversity and haplotype composition in the NWIP correlate with the date of first occurrence of C. neritea at each site rather than with geographical location. Although this pattern evokes the genetic signature expected under a serial-founder colonization model from a single initial enclave, a comparison with samples from potential source populations suggests that the NWIP probably experienced several independent reintroductions. The jump dispersal pattern of C. neritea in the NWIP, together with the observation that populations established in the same year are genetically undifferentiated, point to human transport as the most plausible explanation for the current range expansion. Despite evidence for human-mediated dispersal, C. neritea managed to develop a seemingly non-random genetic pattern in the NWIP. It is suggested that caution must be exerted when interpreting genetic patterns in invaders. 相似文献
102.
Christopher R. Lamb MA VetMB DACVR DECVDI Penny J. Croson BVet Med Rodolfo Cappello DVM DECVN Giunio Bruto Cherubini DVM 《Veterinary radiology & ultrasound》2005,46(1):17-22
To describe the signs that may be associated with intracranial inflammatory conditions, magnetic resonance (MR) images of 25 dogs that had inflammatory cerebrospinal fluid (CSF) were mixed with those of a control group of 40 dogs that had CSF negative for inflammatory disease and reviewed without knowledge of the clinical signs or diagnosis. CSF was considered inflammatory if the protein level was > 0.25 g/l and the white cell count was > 5 mm(-3). Abnormalities were found by MR imaging in 19 (76%) dogs with inflammatory CSF. Two dogs had focal lesions, 10 had multifocal lesions, and seven had diffuse lesions. Lesions affected all divisions of the brain. Mass effect was identified in seven (28%) dogs, including one that had a choroid plexus carcinoma. Lesions were hyperintense in T2-weighted images in 18 dogs and hypointense in T1-weighted images in six dogs. Multifocal or diffuse intraaxial lesions that were hyperintense in T2-weighted images were observed in 17 (68%) dogs with inflammatory CSF. Administration of gadolinium resulted in enhancement of intraaxial lesions in nine (36%) dogs and enhancement of meninges in seven (28%) dogs. Six (24%) dogs with inflammatory CSF had images interpreted as normal. 相似文献
103.
Rodolfo Zocchi 《Journal of pest science》1960,33(11):161-164
Ohne Zusammenfassung 相似文献
104.
Angel H. Alvarez Abel Gutiérrez-Ortega Rodolfo Hernández-Gutiérrez 《Canadian journal of veterinary research》2015,79(4):339-342
Mannheimia haemolytica and Histophilus somni are frequently isolated from diseased cattle with bovine respiratory disease (BRD). They compromise animal lung function and the immune responses generated are not sufficient to limit infection. Identification of specific immunogenic antigens for vaccine development represents a great challenge. Immunogenic proteins were identified by immunoproteomic approach with sera from cattle immunized with a commercial cellular vaccine of M. haemolytica and H. somni. Proteins of M. haemolytica were identified as solute ABC transporter, iron-binding protein, and hypothetical protein of capsular biosynthesis. Histophilus somni proteins correspond to porin, amino acid ABC transporter, hypothetical outer membrane protein, cysteine synthase, and outer membrane protein P6. Although these antigens share strong similarities with other proteins from animal pathogens, the ABC system proteins have been associated with virulence and these proteins could be considered as potential vaccine candidates for BRD. 相似文献
105.
Federica Gilardelli Sergio Sgorbati Sandra Citterio Rodolfo Gentili 《Land Degradation \u0026amp; Development》2016,27(2):316-324
The main goal of quarry restoration is to convert degraded, unproductive areas into new, self‐sustaining ecosystems that develop into highly natural environments. With the aim to individuate the best practices for restoring limestone quarries, we investigated the short‐term effects on vegetation features and economic advantages of three restoration approaches. These approaches included tree and shrub planting, no herb layer, or a commercial seed mixture or hayseed. The different approaches were tested in a limestone quarry within the Botticino extractive basin (N‐Italy). A donor grassland area of hayseed and a quarry area that had undergone spontaneous revegetation over a decade were used as control areas. We surveyed the vegetation plots to investigate the structure and the productivity of the herbaceous layers; collecting data on plant species cover, the mean plant height, the tree and shrubs mortality and biomass enabled us to perform gradient analysis. The main differences between the sites were due to biotic factors; specifically, vegetation cover was affected quite differently by the different restoration approaches. Restoration with commercial seed mixture resulted primarily in dense stands of Lolium perenne that caused an increase in shrub and tree mortality. Cost–benefit analysis showed that despite hayseed being the most expensive approach in terms of cost and time, it ensured higher species diversity, vegetation structure and greening. Our results highlighted that autochthonous plant materials can improve excavation‐areas restoration by both contrasting the colonisation of non‐native species and increasing natural regeneration and biodiversity levels. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
106.
Francesca Beccati Rodolfo Gialletti Fabrizio Passamonti Sara Nannarone Antonio Di Meo Marco Pepe 《Veterinary radiology & ultrasound》2015,56(1):68-76
Septic arthritis/tenosynovitis in the horse can have life‐threatening consequences. The purpose of this cross‐sectional retrospective study was to describe ultrasound characteristics of septic arthritis/tenosynovitis in a group of horses. Diagnosis of septic arthritis/tenosynovitis was based on historical and clinical findings as well as the results of the synovial fluid analysis and/or positive synovial culture. Ultrasonographic findings recorded were degree of joint/sheath effusion, degree of synovial membrane thickening, echogenicity of the synovial fluid, and presence of hyperechogenic spots and fibrinous loculations. Ultrasonographic findings were tested for dependence on the cause of sepsis, time between admission and beginning of clinical signs, and the white blood cell counts in the synovial fluid. Thirty‐eight horses with confirmed septic arthritis/tenosynovitis of 43 joints/sheaths were included. Degree of effusion was marked in 81.4% of cases, mild in 16.3%, and absent in 2.3%. Synovial thickening was mild in 30.9% of cases and moderate/severe in 69.1%. Synovial fluid was anechogenic in 45.2% of cases and echogenic in 54.8%. Hyperechogenic spots were identified in 32.5% of structures and fibrinous loculations in 64.3%. Relationships between the degree of synovial effusion, degree of the synovial thickening, presence of fibrinous loculations, and the time between admission and beginning of clinical signs were identified, as well as between the presence of fibrinous loculations and the cause of sepsis (P ≤ 0.05). Findings indicated that ultrasonographic findings of septic arthritis/tenosynovitis may vary in horses, and may be influenced by time between admission and beginning of clinical signs. 相似文献
107.
Yenitze E. Fimbres‐Acedo Rodolfo Garza‐Torres Masato Endo Rosalía Servín‐Villegas Kevin M. Fitzsimmons Maurício G. C. Emerenciano Francisco J. Magalln‐Barajas 《Aquaculture Research》2019,50(11):3326-3342
Recirculating aquaculture systems (RASs) are an efficient method for developing sustainable aquaculture and the development of a feed strategy for RASs could be a key factor for the success of culturing Oreochromis niloticus. The daily protein intake (DPI) mathematical function related to body weight (BW) was designed (DPI = ?3.818 ln (BW) + 30.158) named DPI 1.0 = 100%. Three feeding rates were established, DPI 1.4, 1.2 and 1.0, and were implemented in an RAS production cycle (100 fish/m3) for 34 weeks. The final growth measurements were 908.0 ± 57.9 g (DPI 1.4), 887.0 ± 113.5 g (DPI 1.2) and 702.2 ± 38.1 g (DPI 1.0) (p < .05), with feed conversion rates (FCRs) of 2.3, 1.9 and 1.9, respectively; the survival was ≥ 98.3% (p > .05) for all treatments. DPI levels conditioned the growth of the fish and the proportion of lipid: protein in the bodies of O. niloticus but not in the fillets. The mathematical function DPI 1.2 = 120% (DPI = ?4.582 ln (BW) + 36.19) used in the RAS at the 40% protein level improved fish growth, the protein efficiency ratio and FCRs. The DPI values were estimated for 49 different cases and feeding strategies showed lower values than most of the different DPI mathematical functions used and cited in this work. Therefore, DPI metric is a good tool that provides the specific requirements of protein for O. niloticus growth, which can enable farmers to ration feed and improve energy use (kWh / fish) and facilitate the integration of RAS with horticulture. 相似文献
108.
Julian Ashford Rodolfo Serra Juan Carlos Saavedra Jaime Letelier 《Fisheries Research》2011,107(1-3):291-299
Chemistry in material laid down prior to capture along the edges of otoliths of Chilean jack mackerel (Trachurus murphyi) showed strong spatial heterogeneity corresponding to hydrographic structure across putative population boundaries between (i) the western and eastern South Pacific Ocean, and (ii) Chile and Peru. Yet the chemistry of the otolith nucleus, in material laid down during early life, showed no evidence supporting the existence of these boundaries. Instead, jack mackerel from New Zealand had similar nucleus chemistry to most sampling areas off South America; and those off southern Peru showed similar nucleus chemistry to most sampling areas off Chile. Strong differences were found between southern and northern Peru, and cluster analysis indicated this was caused by a group of fish off northern Peru with chemistry found nowhere else. Most other fish grouped in two clusters, which showed properties suggesting correspondence with a major spawning zone in oceanic water off central Chile, and a smaller area in coastal water off northern Chile, characterized by similar sea surface temperature, lack of westward transport, and low kinetic energy. Rather than discrete populations separated by boundaries, these results suggest complex spatial structure defined by environmentally mediated survival and connectivity: fish caught off New Zealand may be of South American origin; the spawning zone off central Chile may supply fisheries around the South Pacific; and spawning off northern Chile may be an important source of fish caught locally and in Peru. However, northern Peru does not supply areas further south. 相似文献
109.
Medical records and magnetic resonance (MR) images of 14 cats with inflammatory diseases affecting the central nervous system (CNS) were reviewed retrospectively. Cases included eight cats with feline infectious peritonitis and two cats with toxoplasmosis. Abnormalities affecting the CNS were observed in MR images in 10 (71%) cats. Intracranial lesions appeared as slightly hypointense foci in T1-weighted images in two (14%) cats, as hyperintense foci in T2-weighted images in seven (50%) cats and as hyperintense foci after intravenous administration of a gadolinium-based contrast medium in 10 (71%) cats. In six cats with lesions in T1- and/or T2-weighted images, additional lesions were visible in T1-weighted images obtained after gadolinium-based contrast medium administration. In three cats, lesions were visible only after contrast medium administration. In our study, MR imaging (MRI) did not appear to detect all cases of CNS inflammation in the population of cats with inflammatory cerebrospinal fluid (CSF); however, MRI adds information about the sites and morphology of intracranial lesions that should help to distinguish between neoplasia and inflammatory conditions and, possibly, between different inflammatory conditions. 相似文献
110.
Carlotta Lambertini Katharina Kluge Marta Lanza-Perea Rodolfo Bruhl-Day Karin S. Kalchofner Guerrero 《Veterinary anaesthesia and analgesia》2018,45(6):865-870