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1.
Extremadura is an extensive region (41,000 km2) located in the Southwest of Spain, where animal husbandry is a very important economical resource. Livestock parasitism of ticks is common in the region and it is favoured by the environmental conditions and management systems. Mediterranean theileriosis (MT) is perhaps the most important tick-borne disease of cattle. Although Theileria annulata has been identified in Extremadura since 1933, little epidemiological information is available. During the last decade, we have conducted different studies with the aim to clarify the epidemiological situation. Laboratory diagnosis, identification of tick species and studies on their seasonal dynamics have been carried out. Moreover, T. annulata was isolated and cultivated and experimental transmission of the parasite was made. Finally, several seroepidemiological tests in livestock from different origins have been performed. From 1991 to 1995 a total of 236 of MT clinical cases have been diagnosed. The following tick species were identified: Hyalomma marginatum marginatum (64.0%), Rhipicephalus bursa (25.6%), Hyalomma lusitanicum (9.6%) and Rhipicephalus sanguineus (0.5%). Clinical cases are detected from May until November with peaks in May-June and October that correspond to the periods of maximum activity of adults of H. m. marginatum and H. lusitanicum, respectively. From our results of seroepidemiological studies the Extremadura region could be considered as endemic for MT. The disease is unstable in semi-extensive systems (dairy cows) and tends to stabilisation on extensive farms for meat and fighting bulls.  相似文献   

2.
Serum samples from 210 wild ruminants collected between 2006 and 2007 in southern Spain were tested for antibodies against bluetongue virus (BTV) by means of a competitive ELISA assay. Eighty-seven of the 210 wild ruminants analysed (41%) showed antibodies against BTV. Statistically significant differences were found in the seroprevalence among species: 66% (65 of 98) for red deer (Cervus elaphus), 50% (ten of 20) for fallow deer (Dama dama), 33% (three of nine) for mouflon (Ovis aries musimon) and 11% (nine of 83) for Spanish ibex (Capra pyrenaica). Overall, the sites where seropositive wild ruminants were found coincide with the areas where BTV had been detected in livestock, but in eastern Sierra Morena, the virus circulated in wild ruminants, although it had not been detected in domestic ruminants in the same areas. Wild ruminants over 1-year of age (sub-adults and adults) had significantly higher seroprevalences than juvenile animals. Statistically significant differences were also observed between BTV seroprevalence and management (free-ranging vs. captivity) with higher prevalence in free-ranging animals. The high seroprevalences obtained suggest that BTV is widespread in wild ruminants in southern Spain. This factor could have an important influence on the evolution of the infection in domestic livestock and indicates the need to include wild ruminant species in BTV surveillance or control programs. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

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Antibodies to Toxoplasma gondii were determined in serum samples from 616 equids (454 horses, 80 mules and 82 donkeys) in a cross-sectional study of 420 herds in Andalusia (Southern Spain), the region with the highest number of equids in Spain. Antibodies to T. gondii were found in 10.8% horses, 15.0% mules and 25.6% donkeys by using the modified agglutination test (MAT) at a cut-off of 1:25. Herd seroprevalence for horses, mules and donkeys was 14.7% (48/327), 23.9% (11/46) and 34.0% (16/47), respectively, and 75 herds (17.8%) had at least one seropositive animal. Significant differences in T. gondii seroprevalence were observed among species, with donkeys having the highest seroprevalence and horses the lowest (P=0.04). Seroprevalence was significantly higher in herds with presence of domestic ruminants. This study is the first report of the presence of T. gondii antibodies in equine species in Spain and the first reporting T. gondii infection in donkeys in Europe. The presence of antibodies is indication of contact with the parasite and therefore, consumption of equine meat could be a potential source of human infection in Spain.  相似文献   

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In southern Spain, within the Chiclana de Segura Formation of red detrital fades, enigmatic structures were found whose origins are discussed here. Each structure is composed of the union of elongated traces, two laterals and a shorter central one. All are concave epireliefs at the top of a sandstone bed whose age is assumed to be Ladinian (Triassic). The sediments formed within a fluvial environment. We describe these imprints, their structures and measurements, and discuss their orientations and associations. The traces probably have an organic origin, and are most likely tracks made by a vertebrate, possibly an archosaur, although no osseous remains have been found to confirm this interpretation.  相似文献   

7.
《Ibis》1871,13(2):205-225
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The intracellular protozoan parasite Theileria annulata causes a severe, and often fatal, disease of pure and cross-bred cattle in tropical and subtropical countries. The present review refers to the importance of innate immunity as far as it is known to date in this infectious disease. Specifically, macrophages and the mediators produced by these cells are outlined. In addition, the latest findings concerning cattle breed differences in susceptibility to T. annulata infection in relation to macrophage activation are discussed.  相似文献   

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Men and Women in Southern Spain: "Domestic Power" Revisited   总被引:1,自引:0,他引:1  
This article offers a definition of "domestic power" and attempts to operationalize this for comparative study of gender relations in southern Europe. It describes male-female relations in two stratified rural towns in Andalusia (southern Spain). The data show that working-class women in these towns, often united with their mothers, are able in many cases to prevail in domestic decision making despite opposition from their husbands. The article explores the cultural and psychological reasons for this apparent inversion of a constituted patriarchal ideal and the relative effect of social class upon male and female power asymmetries. The implications of limited access of male fieldworkers to Andalusian women are briefly addressed. Finally, these findings are discussed in the light of broader epistemological issues in gender study.  相似文献   

12.
The phase-out of methyl bromide due to concerns regarding ozone depletion in the stratosphere has imposed the need of developing alternatives less aggressive to the environment. The use of 1,3-dichloropropene (1,3-D) and chloropicrin (Pic) has extended in the last years, and has become essential to maintain strawberry production in Southern Spain, the main producer within the EU. However, their uncertain effects on the environment have become a new obstacle for their future use, and scientific evaluation of their toxicity is necessary to assess their impact on the environment. In this paper, we use the nematode assemblage as indicator of the effects of 1,3-D, Pic and 1,3-D + Pic on non-target soil fauna, and to infer their effects on soil food web functioning in two commercial strawberry farms in Southern Spain. Although affected, the abundance of bacterial-feeding nematodes did not differ among treatments due to compensatory growth of opportunistic nematodes. Fungal-feeding nematodes were strongly reduced by the fumigants, probably due to direct fumigants toxicity and to alterations on the fungal decomposition channel. Taxa richness and soil food web indices were also affected by the treatments. The ratio fungal to bacterial-feeding nematode abundances is proposed as the best indicator of the short and medium term effects of fumigants on non-target soil organisms. Implications of such findings on soil food web functioning and recovery are discussed.  相似文献   

13.
In Tunisia, tropical theileriosis (Theileria annulata infection of cattle) is one of the major diseases affecting cattle in the summer. Each year about 2,500 clinical cases are recorded in the country, mainly in pure-bred animals. An attempt was made in the North of Tunisia to estimate the direct cost related to clinical cases of TT. In the endemic regions, three states of endemicity were described according to cattle age categories at highest disease risk: (i) endemic stability, (ii) low endemic instability, (iii) high endemic instability. The characterisation of these endemic situations, which are conditioned by the levels of the vector tick population and the quantitative aspects of the infection in ticks, are highly relevant for the development of a live attenuated cell line vaccine against TT targeting the cattle population at disease risk in Tunisia. A research programme was set up to develop the attenuation of four local parasite stocks. Two cell lines infected with two distinct T. annulata stocks were tested in the field on pure-bred animals of different age groups from regions with high disease incidence. The vaccination with each of the two cell lines showed a high efficacy. However significant differences in vaccine reactions rates were observed between the two attenuated cell lines emphasising the importance of achieving an optimal balance between protection and vaccine tolerance particularly in pure-bred lactating cows.  相似文献   

14.
A total of 153 blood samples were collected all over the Sicilian island in 15 farms. 29.4% and 25.5% were PCR positive for Theileria annulata and T. buffeli/orientalis respectively. 15.7% of cattle blood samples showed a mixed infection with both Theileria species. Each farm showed an infection rate ranging from 0% to 100%. Hyalomma marginatum and Boophilus annulatus were the most common ticks collected in April and November 1998 respectively. The aim of the present work was to investigate on haemoparasite species spread in Sicily. Ticks vectors involved in the transmission, distribution, risk areas and seasons, state of healthy carrier, are also discussed in this paper.  相似文献   

15.
The results of seasonality studies undertaken with prehistoric faunal materials from the Greenwich Cove site in coastal Rhode Island are presented. Growth patterns in shells of the hard clam or quahog (Mercenaria mercenaria) are used to reconstruct the time(s) of year this species was collected. A controlled study of seasonal growth provides a comparative baseline for this analysis. Seasonality of white-tailed deer (Odocoileus virginianus) hunting is interpreted through the examination of growth structures in preserved teeth. The seasonal availability of migratory species is also considered. Relatively year-round coastal settlement is proposed for the final centuries of the prehistoric period.  相似文献   

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The occurrence of the carpet weed Galenia secunda (L. fil.) Sond. (Aizoaceae) has been reported in Southern Spain. G. secunda is a prostrate perennial species native to South Africa. In this paper, the current distribution of G. secunda and the main habitats invaded in Southern Spain, are reported. The distribution survey revealed an area of occupancy of 92 ha and an extent of occurrence of 14,250 ha for this species, thus suggesting an early stage of invasion. Since the first citation of this species in Spain (1965), our current data (2007) support a rapid spread and invasiveness of G. secunda as a result of an intense rate of coastal development. G. secunda was more often found near roads, because roads facilitate seed dispersal. G. secunda also appeared in other coastal natural habitats such as sand dunes, where G. secunda forms dense monospecific mats. Studies on its invasion potential and impacts in natural habitats are recommended and control measures should be developed to prevent future expansion.  相似文献   

18.
Abies pinsapo fir forests are remnant of temperate-like coniferous forests currently subjected to the typical seasonal constraints of Mediterranean-type climates. We have examined for the first time, P availability and cycling in A. pinsapo forests from southern Spain by using both, measurements of concentrations of soil P fractions (resin extractable P, bicarbonate extractable P and NaOH extractable P) and rates of P supply to (P solubilization, P mineralization and phosphomonoesterases (PMEase activity) and P immobilization from the soil solution. Soils from A. pinsapo stands differing in lithology (serpentinitic and calcareous substrates) and successional status (from young-agradative to old-growth stages) were chosen for this study. Labile organic P fractions, PMEase activity and rates of P gross mineralization and immobilization were significantly higher in agradative stands on serpentines than in successionally comparable calcareous stands. This suggests an important role of the organic P subcycle in the A. pinsapo stand on serpentine. On calcareous lithology, PMEase activity and all soil P transformation rates significantly increased throughout the successional series. Similarly, all organic and inorganic P fractions measured in old-growth forests showed the maximum values of the series. These trends fit the predictions of standard patterns of P cycling changes along with succession, in which P supply to plants greatly depends on solubilization from mineral forms at early-to-mid successional stages, whereas the importance of processes related to the organic P subcycle increases as succession progresses.  相似文献   

19.
本研究旨在通过观察南方鲇血清与其红细胞的交叉反应以鉴定南方鲇的血型.实验结果表明:南方鲇的血清与同种其他个体的红细胞进行交叉反应时均未出现凝集现象,这表明南方鲇可能不存在血型或南方鲇具备血型但血清中相应的凝集素含量不足.以南方鲇的红细胞为抗原免疫日本种大耳白兔制备的抗血清与南方鲇的红细胞进行交叉反应,出现了不同程度的凝集反应,这表明南方鲇存在血型.据上述两个实验结果可以推断,南方鲇可能存在4种血型,分别命名为NA、NB、NAB和NO型;同时也证实,在鉴定南方鲇血型的研究中,通过制备抗血清与红细胞进行交叉反应的方法更为可靠.  相似文献   

20.
The nymphs ofEphemerella ignita occurred in all months except October in the Bere Stream at Bere Heath, a small chalk stream in Southern England. Peak densities of 1,498 m–2 and 753 m–2 were recorded in May by two sampling methods used simultaneously. The seasonal patterns of growth and abundance are compared with the findings of other authors. A maximum biomass of 0.82 g m–2 preserved dry weight is compared with figures for two of the most common invertebrate groups present; the Simuliidae and Oligochaeta.  相似文献   

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