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81.
Vesco G Buffolano W La Chiusa S Mancuso G Caracappa S Chianca A Villari S Currò V Liga F Petersen E 《Veterinary parasitology》2007,146(1-2):3-8
The aim of the study was to determine the burden of Toxoplasma gondii-infections in sheep in Sicily, southern Italy and the risk factors for infection. Sera from 1961 sheep were collected just before slaughtering from 62 farms located in 8 out of 9 Sicilian administrative districts. The sera were analysed for Toxoplasma-specific IgG antibodies using commercially available enzyme-linked immunosorbent assay. Sheep less than 4 weeks old were further analysed by ELISA for Toxoplasma-specific IgM-antibodies. Data on farm size and location were obtained from slaughterhouse sanitary reports and through structured telephone interviews of the veterinary officers from public health districts. The overall seroprevalence of Toxoplasma-specific IgG-antibodies were 49.9% (937/1876) by ELISA. Eighty-seven (54/62) percent of the farms had at least one Toxoplasma-positive animal. All the farms fed the animals outdoor on pasture and only one was claiming organic farming. Having cats on the farm, age of the animals, farm size and the use of surface water sources for drinking were all significantly associated with T. gondii-infected animals on the farm. T. gondii infection in mutton used for human consumption is very prevalent, and eating unprocessed sheep and lamb meat has a high risk of transmitting infections to humans. The presence of cats on the farm, farm size and using surface water as drinking water for the animals were risk factors for infection in sheep, with age as a significant confounder. 相似文献
82.
Le Garreres A Laroute V De La Farge F Boudet KG Lefebvre HP 《Journal of Feline Medicine and Surgery》2007,9(2):89-96
The objectives of this study were to compare assay methods for plasma creatinine (Pl-creat) in cats and to describe the disposition of creatinine and iohexol in 12 healthy and moderately azotaemic cats. Exogenous creatinine and iohexol were injected simultaneously by intravenous bolus, and repeated blood samples were taken to determine the pharmacokinetic parameters of each marker. Pl-creat was assayed by high-performance liquid chromatography (HPLC), Jaffé and enzymatic methods. The enzymatic method was shown to be more reliable than the Jaffé method. Two stereoisomers, exo- and endo-iohexol were identified. The plasma clearance of creatinine (2.3+/-0.66 ml/min/kg) was significantly higher (P<0.001) than that of exo-iohexol (1.7+/-0.40 ml/min/kg). The volume of distribution (447+/-97 ml/kg) and elimination half-life (181+/-77 min) of creatinine were also higher (P<0.001) than those of exo- and endo-iohexol. The estimated daily endogenous production of creatinine was 65+/-23 mg/kg. None of the pharmacokinetic parameters was changed by the azotaemic status of the animals. 相似文献
83.
香草兰营养特性的研究 总被引:9,自引:3,他引:6
对海南不同生产水平的香草兰种植园植株的养分调查分析,及N,P,K,Ca,Mg肥料的盆栽试验,研究香草兰的营养特性。结果表明,香草兰植株养分的吸收量以K〉Ca〉N〉Mg〉P,叶片以Ca〉K〉N〉Mg〉P;结果植株养分吸收量N:P:K:Ca:Mg=1.00:0.24,1.39:1.18:0.48,盆栽幼苗N:P:K:Ca:Mg=1.00:0.10:1.38:1.23:0.33;高产园植株Ca,P含量极 相似文献
84.
Optimal egg viability storage conditions in two commercial fairy shrimps (Crustacea: Branchiopoda: Anostraca) from Thailand 下载免费PDF全文
Optimal egg viability storage conditions for two commercial fairy shrimps, Branchinella thailandensis and Streptocephalus sirindhornae, were investigated. Eggs for each treatment were kept under eight different conditions at four different temperatures for 24 months. Every 2 months, representative eggs were hatched to evaluate hatching percentages. Low temperature and oxygen, darkness and dry conditions significantly influenced egg hatchability of both species. Undehydrated eggs hatchability in all conditions ranged from 0 to 10% in S. sirindhornae and 0 to 20% in B. thailandensis. Hatching percentages of B. thailandensis were higher than those of S. sirindhornae. Hatchability under all experimental regimes continuously decreased over time, except for dry eggs stored at ?18°C in dark‐anoxic conditions. Hatchability was markedly delayed in both species over time. We demonstrate that both species’ eggs can be stored at ?18°C at least for 24 months with high hatchability in B. thailandensis (80%) and S. sirindhornae (60%) under dry, dark, anoxic conditions. 相似文献
85.
86.
黄芪多糖对仿刺参非特异性免疫功能的影响 总被引:5,自引:0,他引:5
向刺参体腔中注射相同体积(500 μl)的无菌黄芪多糖溶液后第1、3、6 d,测定体腔液中溶菌酶、超氧化物歧化酶、碱性磷酸酶活性及补体C3的含量,研究黄芪多糖对刺参免疫系统的影响.每头刺参多糖含量分别达0.2、0.4、0.6 mg,溶菌酶、超氧化物歧化酶、碱性磷酸酶活性及补体C3含量均在注射后第3 d达到最高,且前3种指标以0.6 mg/头剂量组最高,分别达到232.25 U/ml,45.1 U/ml,966.5 nkat/L;C3含量则以0.4 mg/头剂量效果最好,达到0.09 g/L.经SPSS软件分析,均与对照组差异显著(P<0.05),表明黄芪多糖具有增强刺参免疫功能的作用. 相似文献
87.
Early life history connectivity of Antarctic silverfish (Pleuragramma antarctica) in the Ross Sea 下载免费PDF全文
Cassandra M. Brooks Jilda Alicia Caccavo Julian Ashford Robert Dunbar Kimberly Goetz Mario La Mesa Lorenzo Zane 《Fisheries Oceanography》2018,27(3):274-287
A recent population hypothesis for Antarctic silverfish (Pleuragramma antarctica), a critical forage species, argued that interactions between life history and circulation associated with glacial trough systems drive circumpolar distributions over the continental shelf. In the Ross Sea, aggregations of eggs and larvae occur under fast ice in Terra Nova Bay, and the hypothesis predicted that dispersing larvae encounter outflow along the western side of Drygalski Trough. The outflow advects larvae towards the shelf‐break, and mixing with trough inflow facilitates return toward the inner shelf. To examine the hypothesis, we compared samples of P. antarctica collected near Coulman Island in the outflow, along Crary Bank in the inflow, and a third set taken over the rest of the Ross Sea. We ruled out misidentification using an innovative genetic validation. Silverfish larvae comprised 99.5% of the catch, and the highest population densities were found in Drygalski Trough. The results provided no evidence to reject the population hypothesis. Abundance indices, back‐calculated hatching dates, length distributions and growth were congruent with a unified early life history in the western Ross Sea, constrained by cryopelagic early stages in Terra Nova Bay. By contrast, a sample in the Bay of Whales revealed much smaller larvae, suggesting either a geographically separate population in the eastern Ross Sea, or westward connectivity with larvae spawned nearby by fish sourced from troughs upstream in the Amundsen Sea. These results illustrate how hypotheses that integrate population structure with life history can provide precise spatial predictions for subsequent testing. 相似文献
88.
Weak effects of habitat type on susceptibility to invasive freshwater species: an Italian case study 下载免费PDF全文
Angela Boggero Alberto Basset Martina Austoni Enrico Barbone Luca Bartolozzi Isabella Bertani Alessandro Campanaro Antonella Cattaneo Fabio Cianferoni Giuseppe Corriero Ambrosius Martin Dörr A. Concetta Elia Gentile Francesco Ficetola Lyudmila Kamburska Gianandrea La Porta Sara Lauceri Alessandro Ludovisi Elda Gaino Enzo Goretti Massimo Lorenzoni Marina Manca Aldo Marchetto Giuseppe Morabito Francesco Nonnis Marzano Alessandro Oggioni Cataldo Pierri Nicoletta Riccardi Giampaolo Rossetti Nicola Ungaro Pietro Volta Silvia Zaupa Diego Fontaneto 《水产资源保护:海洋与淡水生态系统》2014,24(6):841-852
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89.
G. Gambino B. Navarro E. M. Torchetti P. La Notte A. Schneider F. Mannini F. Di Serio 《European journal of plant pathology / European Foundation for Plant Pathology》2014,140(2):199-205
Five viroid species have been reported from grapevine. Hop stunt viroid (HSVd) and Grapevine yellow speckle viroid 1 (GYSVd-1) are distributed worldwide, whereas Grapevine yellow speckle viroid 2 (GYSVd-2), Australian grapevine viroid (AGVd) and Citrus exocortis viroid (CEVd) are found only sporadically. However, the presence of AGVd and GYSVd-2 in several countries, including China, Turkey and Label="Tunisia" gaAction="reference-keyword">Tunisia, suggests a wider dissemination, possibly also in Europe, where AGVd has never been found and GYSVd-2 has been occasionally identified in Italy. Taking advantage of a multiplex Label="RT-PCR" gaAction="reference-keyword">RT-PCR assay recently developed for detecting simultaneously these five viroids, vines growing in Italy in commercial vineyards and germplasm collections were surveyed. Besides confirming the widespread presence of HSVd and GYSVd-1 in the field, GYSVd-2 and/or AGVd were identified in two grapevine table cultivars (Sultanina Bianca and Red Globe) from germplasm collections. Tests extended to vines cultivated in southern Italy confirmed the presence of both viroids, which were further characterized. No major sequence divergences between the AGVd and GYSVd-2 variants from Italy and those previously described from other countries were observed. Phylogenetic analysis supported the close relationships among AGVd variants from Italy, Label="Tunisia" gaAction="reference-keyword">Tunisia and Australia. To our knowledge this is the first report of AGVd in Europe and the first molecular characterization of GYSVd-2 isolates from a European country. 相似文献
90.
Swine dysentery (SD) results from infection of the porcine large intestine with the anaerobic intestinal spirochaete Brachyspira hyodysenteriae. Diagnosis of SD traditionally has relied on detecting the spirochaete in the faeces of acutely affected pigs. To date simple and reliable serological assays that can be applied as a diagnostic tool at the herd level have not been available. In the current study a recombinant histidine tagged 29.7 kDa lipoprotein of B. hyodysenteriae (His6-Bhlp29.7) was used as an ELISA plate-coating antigen. Sera (n=1121) from slaughter-aged pigs on 19 farms were tested in this ELISA. Following optimization of the ELISA conditions using hyperimmune control sera, a set of 464 sera from slaughter-aged pigs from five herds where SD did not occur was tested. From these results a suitable cut-off value for herd negativity was defined as the mean optical density reading plus three standard deviations. Testing of 337 pig sera from six farms with SD then showed that the sensitivity of the test at the herd level was 100%, with all six farms having one or more serum samples exceeding the cut-off value for negativity. Finally, 320 sera from eight herds suspected of having SD were examined. Four of these herds were shown to have pigs with titres consistent with SD. The true health status of the other four herds that were serologically negative could not be confirmed. In conclusion, when used on sets of 40 sera from slaughter-aged pigs the His6-Bhlp29.7 ELISA as established proved to be a useful adjunct to the diagnosis of SD at the herd level. 相似文献