The tidepool shrimp,Palaemon ritteri Holmes,constitutes a novel host to the white spot syndrome virus          下载免费PDF全文

A Sánchez‐Paz  B Terán‐Díaz  T Enríquez‐Espinoza  T Encinas‐Garcia  I Vázquez‐Sánchez  F Mendoza‐Cano 《Journal of fish diseases》2015,38(7):613-620

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Ultrastructure of Lingual Papillae in Common Chimpanzee (Pan troglodytes) Foetus,Newborn and Adult Specimens          下载免费PDF全文

J. F. Pastor  M. Barbosa  F. J. De Paz  I. San José  M. Levanti  J. M. Potau  J. A. Vega  R. Cabo 《Anatomia, histologia, embryologia》2017,46(5):431-438

Among primates, the two recognized species of chimpanzees (common chimpanzee, Pan troglodytes; pygmy chimpanzee, Pan paniscus) are considered to be the most similar to humans. Importantly, in mammals, the food intake behaviour largely determines the tongue morphology, including the type, proportion and distribution of gustatory and non‐gustatory tongue papillae. The lingual papillae form during its development and mature in post‐natal life depending on the different feeding. In this study, we have used scanning electron microscopy to analyse the age‐related changes in the lingual papillae of foetal, newborn and adult P. troglodytes. Four main types of lingual papillae, denominated filiform, fungiform, foliate and vallate, and one subtype of filiform papillae called conical papillae, were found. The main age‐related changes observed in all kinds of papillae were a progressive keratinization and morphological complexity along the lifespan. During the foetal period, there was scarce keratinization, which progressively increases in young animals to adulthood. The number of filiform increased with ageing, and both filiform and fungiform papillae in adult tongues are divided into pseudopapillae. On the other hand, the vallate papillae vary from smooth simple surfaces in foetal tongues to irregular surfaces with grooves and pseudopapillae (microscopic papilla‐shaped formations within the papilla itself) in adults. These results describe for the first time the age‐related variations in the three‐dimensional aspect of lingual papillae of the chimpanzee tongue and provide new data to characterize more precisely these structures in the human closest specie.  相似文献   

Soil erosion under simulated rainfall in relation to phenological stages of soybeans and tillage methods in Lages, SC, Brazil     

F.L. Engel  I. Bertol  S.R. Ritter  A. Paz Gonzlez  J. Paz-Ferreiro  E. Vidal Vzquez 《Soil & Tillage Research》2009,103(2):216

Soil tillage may increase vulnerability to water erosion, whereas no tillage and other conservation cultivation techniques are viewed as strategies to control soil erosion. The objective of this research was to quantify runoff and soil losses by water erosion under different soil tillage systems at the Santa Catarina Highlands, southern Brazil. A field study was carried out using a rotating-boom rainfall simulator with 64 mm h⁻¹ rainfall intensity on a Typic Hapludox, between April 2003 and May 2004. Five rainfall tests were applied along successive cropstages. Surface cover was none (fallow) or soybean (Glycine max, L.). Five treatments were investigated, replicated twice. These treatments were conventional tillage on bare soil (BS) as a control treatment and the following treatments under soybean: conventional tillage (CT), no tillage over burnt crop residues on never before cultivated land (NT-B), no tillage over desiccated crop residues, also on never before cultivated land (NT-D) and traditional no tillage over desiccated crop residues on a soil tilled 4 years before this experiment (NT-PT). Water losses by surface runoff seemed to be more influenced by vegetative crop stadium than by tillage system and consequently a wide range of variation in surface runoff was found, following successive cropstages. The most efficient tillage system in reducing surface runoff and soil losses was no tillage, particularly the NT-PT treatment. Sediment losses were more influenced by tillage system than water losses. In the NT-B, NT-D and NT-PT treatments the rate of sediment losses along the crop vegetative cycle showed a tendency to increase from the first to the second cropstages and later to decrease from the third cropstage onwards. In the conventionally tilled treatment (CT) soil losses were greater than in any of the no tillage treatments (NT-D, NT-B and NT-PT) during the initial growth periods, but at the end of the vegetative period differences in sediment rates between tilled and non-tilled treatments tended to be smaller. In the BS control treatment, soil losses progressively increased following the vegetative growth season of soybean.  相似文献   

Nondestructive determination of total soluble solid content and firmness in plums using near-infrared reflectance spectroscopy     

Paz P  Sánchez MT  Pérez-Marín D  Guerrero JE  Garrido-Varo A 《Journal of agricultural and food chemistry》2008,56(8):2565-2570

The fruit industry requires rapid, economical, and nondestructive methods for classifying fruit by internal quality, which can be built into the processing line. Total soluble solid content and firmness are the two indicators of plum internal quality that most affect consumer acceptance. These parameters are routinely evaluated using methods which involve destruction of the fruit; as a result, only control batches can be analyzed. The development of nondestructive analytical methods would enable the quality control of individual fruits. Near-IR spectroscopy (NIRS) was used to assess total soluble solid content (SSC, degrees Brix) and firmness (N) in intact plums. A total of 720 plums (Prunus salicina L. cv. 'African Pride', 'Black Diamond', 'Fortune', 'Laetitia', 'Larry Anne', 'Late Royal', 'Prime Time', 'Sapphire', and 'Songold') were used to obtain calibration models based on reference data and near-IR spectral data. Standard errors of cross-validation (SECV) and coefficients of determination for cross-validation (r(2)) were (0.77 degrees Brix; 0.83) for total soluble solids content and (2.54 N; 0.52) for firmness. Results suggest that NIRS technology enables fruit to be classified in terms of total soluble solid content and firmness, thus allowing increased sampling of each production batch and ensuring a given quality with greater precision and accuracy.  相似文献   

Estudio comparado de las Papilas linguales del Gato (Felis catus) y del Conejo (Oryctolagus cuniculus) mediante el Microscopio electrónico de barrido     

C. A. Chamorro    J. Sandoval    J. G. Fernandez    M. Fernandez  P. de  Paz 《Anatomia, histologia, embryologia》1987,16(1):37-47

Compared studies of the lingual papillae of the cat ( Felis catus ) and the rabbit ( Oryctolagus cuniculus ) by scanning electron microscopy
The morphologic characteristics of the principal lingual papillae of the cat and the rabbit were studied and compared through the use of scanning electron microscopy. The fungiform papillae of the rabbit demonstrates an annular pad which is absent in the cat. Both species demonstrated openings of taste pores on these papillae. The vallate papilla demonstrated pseudopapillae in both species. In the rabbit, however the annular pad is quite rudimentary. These papillae also demonstrate taste pores on their surface in both species. The foliate papillae were quite different between the species. In the cat, they were digitiform and in the rabbit they were represented by a number of laminae. Few gustatory pores were observed in the cat, but pores were numerous in the rabbit. In both species there were three forms of mechanical papillae (smooth conical, scaly conical and filiform). These papillae are described according to location and density.  相似文献   

Reactions of peripheral blood mononuclear cells (PBMC) of camels with monoclonal antibodies against ruminant leukocytes     

Ungar-Waron H  Yagil R  Brenner J  Paz R  Partosh N  Van Creveld C  Lubashevsky E  Trainin Z 《Comparative immunology, microbiology and infectious diseases》2003,26(2):137-143

The particular immune system of the camel has been but little investigated. In this work circulating camel peripheral blood mononuclear cells (PBMC) were studied by flow cytometry. Monoclonal antibodies (mAbs) raised against ruminant leukocytes were used for the detection of cell surface antigens. Monoclonals to T-cell markers, CD4 (CACT138A) and CD8 (CACT80C), exhibited no reactivity towards camel PBMC in contrast to their reactivity to PBMC of other ruminant species and those of cattle in particular. A relatively high percentage (29.1+/-8.9%) of camel PBMC reacted with a non-immunoglobulin cell surface marker, B-B2, comparable to the reactivity of bovine PBMC. The B-B7 cell marker revealed 22.4+/-10.0% of reactive camel PBMC while the CD45 leukocyte common antigen was identified only on 19.4+/-3.1% of camel PBMC as compared to 74.7+/-4.9% for bovine PBMC. IgM (PIg45A) was detected on 9.1+/-1.4% of camel PBMC and on 46.6+/-19.5% of the bovine PBMC. Double fluorescent labeling with two B-cell markers and an anti-ruminant lambda light-chain mAb revealed 7-9% of cells bearing both B and lambda L-chain markers. Light chain reactivity was also assessed using an anti-goat F(ab')(2) antiserum. The values obtained, 14.3+/-5.8% for the camel and 47.8+/-2.7% for the cattle, are close to the values observed for surface IgM. These data suggest that camels, like other ruminants, possess L-chain bearing cells of the B-cell lineage. However, in the camel, Igs are different in that in addition to regular four chain Igs, about 65% of them possess two heavy chain Igs devoid of light chains. Because different sets of V(H) gene segments are used by four and two chain Igs, it is possible that there might be two lineages of B-cells each secreting a different form of antibodies.  相似文献   

Experimental infection of calves with bovine leukemia virus (BLV): an applicable model of a retroviral infection     

Ungar-Waron H  Paz R  Brenner J  Yakobson B  Partosh N  Trainin Z 《Veterinary immunology and immunopathology》1999,67(2):195-201

An experimental model of chronic infection with bovine leukemia virus (BLV) was established in young calves within a relatively short time. In the sera of all infected calves, precipitating antibodies were detected within 5 weeks after infection but upon disease progression pattern of cellular profiles varied. Three calves exhibited transient lymphocytosis 3-5 weeks after infection, two became persistent lymphocytotic (PL+) by that time and one stayed non-lymphocytotic (PL-) for 11 weeks and became PL+ after 4.5 months. Eventually all infected calves became PL+ by the end of the experiment, 6-12 months after infection. Increase of total counts of peripheral blood mononuclear cells (PBMC) related to polyclonal expansion of B-cells. The latter was assessed in all infected calves where the expansion of CD5-bearing cells (B+ CD5+) correlated with increase or decrease of total PBMC counts. Other cell populations such as CD4 and CD8 were also affected. Percentages decreased by 5 weeks after experimental infection to about half their original values though actual cell numbers stayed relatively stable. The experimental model we established compared well with field cases of naturally BLV-infected cattle and thus permitted the investigation of the disease at early stages of infection.  相似文献   

Ovum Pick-up in Sheep: a Comparison between Different Aspiration Devices for Optimal Oocyte Retrieval     

C Rodríguez  L Anel  M Alvarez  E Anel  JC Boixo  CA Chamorro  P de  Paz 《Reproduction in domestic animals》2006,41(2):106-113

In vivo ovum pick-up (OPU) in sheep may be improved with a proper choice of aspiration elements (needle and tubing) and aspiration vacuum pressure. In the present study, two experiments were carried out. In Expt 1, visible follicles in ovaries of slaughtered ewes (treated separately according to their diameters: small<3 mm, medium 3-5 mm and large>5 mm) were aspirated using different combinations of the three studied factors such as aspiration flow rate (10, 20, 30, 40 and 50 ml water/min), needle gauge (18 and 20 G) and tubing inner diameter (1, 2 or 3 mm internal diameter). In Expt 2, a study with two 18 G needles of different lengths (18 G: 82 mm; 18 GL: 600 mm) was carried out, using ovaries obtained post-mortem, and performing in vivo laparoscopic follicular aspiration on ewes. We considered good quality oocytes as those with both complete compact cumulus and a homogeneous cytoplasm. Recovery rate, proportion of good quality oocytes (good quality oocytes/100 oocytes recovered) and overall efficiency (good quality oocytes/100 follicles aspirated) were noted. In Expt 1, aspiration flow rate affect remarkable proportion of good quality oocytes (69.5%, 50.5%, 44.8%, 36.5% and 28.3% for flows from 10 to 50 ml/min respectively, p<0.05). Needle gauge did not affect aspiration device efficiency. Thin and intermediate tubings were more effective (overall efficiency rates: 34.9%, 32.3% and 28.1% for 1, 2 and 3 mm respectively, p<0.05). Follicle size did not affect recovery rate, but proportion of good quality oocytes was higher for large (77.9%) and medium (64.4%) follicles (p<0.05). Finally, some combinations of the aspiration device showed greater effectiveness. In Expt 2, needle length did not influence recovery rate, but good quality oocytes rate was significantly modified both post-mortem and in vivo (good quality rate for 18 G vs 18 GL needles: 69.5% vs 47.7% and 58.1% vs 25.4%, post-mortem and in vivo respectively, p<0.05). We conclude that low-aspiration flow rates (10 and 20 ml/min) with thin or intermediate tubings (1 and 2 mm), and any short needle (18 G or 20 G) are the most adequate aspiration factors for OPU in sheep.  相似文献   

Testing the role of allelochemicals in different wheat cultivars to sustainably manage weeds     

Yedra Vieites-Álvarez  Paz Otero  Miguel Angel Prieto  Jesus Simal-Gandara  Manuel J Reigosa  Adela M Sánchez-Moreiras  M. Iftikhar Hussain 《Pest management science》2023,79(7):2625-2638

Background

Selecting wheat varieties with allelopathic potential or high competitiveness against weeds is a sustainable solution for organic farming to eliminate the use of synthetic herbicides. Wheat is one of the most economically important crops. This study focuses on screening the allelopathic or competitive potential of four wheat cultivars, Maurizio, NS 40S, Adesso and Element, on two weeds of interest due to acquired herbicide resistance, Portulaca oleracea and Lolium rigidum, through germination and growth bioassays and the identification and quantification of benzoxazinoids (BXZs) and polyphenols (phenolic acids and flavonoids).

Results

The different cultivars showed different abilities to manage surrounding weeds and different capacity to exude or accumulate specialized metabolites in the presence of those weeds. Furthermore, each cultivar behaved differently depending on the weed present in the medium. The most efficient cultivar to control the tested monocot and dicot weeds was Maurizio, as it effectively controlled germination and growth of L. rigidum and P. oleracea while exuding large amounts of benzoxazinones through the roots, especially the hydroxamic acids 2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one and dihydroxy-2H-1,4-benzoxaxin-3(4H)-one. By contrast, NS 40S, Adesso and Element showed the potential to control the growth of just one of the two weeds through allelopathy or competition.

Conclusion

This study reveals that Maurizio is the most promising wheat cultivar for sustainable weed control, and that the screening of crop varieties with allelopathic potential, which results in the displacement of synthetic herbicides, is an immediate solution in ecological and sustainable agriculture. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.  相似文献   

The Effect of Landscape Conservation Measures in Changing Landscape Patterns: A Case Study in Mediterranean Mountains     

Teodoro Lasanta  Estela Nadal‐Romero  Paz Errea  Jos Arnez 《Land Degradation \u0026amp; Development》2016,27(2):373-386

Mediterranean mountain landscapes have high ecological and cultural values. However, since 1950, a large number of these landscapes have been subject to degradation as a consequence of land abandonment. Some regional administrations have enacted measures that favour the regeneration of pasturelands through scrubland clearing. The aim of this study was to evaluate the consequences of clearing and the regeneration of pasturelands on landscape structure and the recovery of extensive livestock in La Rioja. The results indicate that between 1986 and 2011 an area of 29,659 ha was cleared in the mountains of La Rioja, although 62·6% of this was cleared in the period 2000–2011. In 1956, the landscape was dominated by cultivated fields, but by 2001, much of the agricultural area had been abandoned and replaced by scrubland, natural woods and reforested areas. Furthermore, the landscape was more fragmented in 1956 than in 2001. The landscape structure varied following clearing, with a doubling in the number of patches and an increase in heterogeneity. The consequences of clearing have included an increase in the area of pastureland and the number of large animals. In addition, the number of farms has decreased, but their mean size has increased. Clearing is an appropriate way for spatial reorganization in marginal mountain areas. It does not require excessive investment but favours the reintegration of abandoned fields and an increase in pasturelands. The results of this study contribute to the debate about reclaiming mountain landscapes affected by human activities and subject to intense degradation processes. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献