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991.
Júnior AF Gonçalves-Pires MR Silva DA Gonçalves AL Costa-Cruz JM 《Veterinary parasitology》2006,136(2):137-145
Canine strongyloidiasis is a parasitic infection caused by the nematode Strongyloides stercoralis and presents a great zoonotic potential. Its confirmation, using coproparasitological methods, is difficult. The detection of serum specific antibodies, however, may facilitate the diagnosis. The aims of this study were to determine the presence of S. stercoralis through the use of parasitological methods and to detect specific antibodies to the parasite in serum samples from domestic dogs by using the indirect fluorescent antibody test (IFAT) on slides and the enzyme-linked immunosorbent assay (ELISA). A total of 215 dogs of various breeds, from the cities of Uberlandia, Araxá and Campo Belo in the State of Minas Gerais, were examined and distributed according to age into the following groups: (I) 19 males and 20 females of 1-2 months old; (II) 11 males and 20 females of 2-month- to 1-year-old and (III) 41 males and 104 females, from 1 to 7 years old. Coproparasitological results showed that 63/215 (29.3%) of the dogs presented some kind of parasite, with two (0.9%) dogs (one from Araxá and the other from Uberlandia) passing S. stercoralis larvae in the feces. Serological results revealed antibodies to S. stercoralis in 45/215 (20.9%) of the dogs, with seropositivity rates of 0% (0/39) in Group I, 22.6% (7/31) in Group II, and 26.2% (38/145) in Group III. No serological cross-reactivity between S. stercoralis and hookworms or Ascaridae was found. Hookworm infections were seen in 31 dogs, but only one of these dogs (infected with both hookworm and Cystoisospora spp.) was S. stercoralis seropositive by IFAT. The present study demonstrated, for the first time, natural S. stercoralis infections in dogs diagnosed by coproparasitological and serological methods. It was concluded that the detection of specific antibodies to S. stercoralis by IFAT and ELISA may contribute to the diagnosis of canine strongyloidiasis. 相似文献
992.
A survey of the prevalence of anthelmintic resistant nematode populations was conducted on 32 sheep farms in the Slovak Republic. In vitro egg hatch test and larval development tests were used for the detection of resistance to benzimidazole anthelmintics and they were compared with in vivo faecal egg count reduction tests. There was agreement in the declaration of resistance between the faecal egg count reduction test and both in vitro tests. The presence of resistant populations was determined on two farms using egg hatch test. In both farms, the LD(50) values were higher than 0.1 microg TBZ/ml, indicating resistance. By using LD(99) values it might be possible to reveal relatively small proportion of resistant larvae in the population. The prevalence of benzimidazole resistance has not change on Slovak sheep farms during last decade. 相似文献
993.
Ornithodoros erraticus is an argasid tick that can transmit severe diseases such as human relapsing fever and African swine fever. In southern Europe O. erraticus lives in close association with swine on free-range pig farms. Application of acaricides for the eradication of O. erraticus from pig farms is inefficient. This is the reason why we tried to develop an anti-O. erraticus vaccine as alternative method of control. Accordingly, we were prompted to investigate the protective possibilities of a midgut membrane extract from the parasite (GME) that has not been studied hitherto. Administration of the GME with Freund's adjuvants (FAs) to pigs and mice induced a protective response able to kill 80% of the immature forms of the parasite in the first 72 h post-feeding and to reduce the fecundity of females by more than 50%. The action of the vaccine is the result of damage to the midgut wall of the argasid, and, in mice, it has been shown that this damage is mediated by activation of the complement system. In pigs, the administration of GME with alum, instead of with FAs, reduced the degree of protection. The protective antigens of the GME were expressed by all the developmental stages examined and are probably proteins from the luminal membrane of midgut epithelial cells. These antigens were seen to be more abundant in recently fed parasites than in fasting specimens, suggesting that their expression is induced after blood ingestion. 相似文献
994.
Carrasco L Raya AI Núñez A Gómez-Laguna J Hernández S Dubey JP 《Veterinary parasitology》2006,137(1-2):180-183
Four Korean squirrels (Tanias siberius) imported in Spain from People's Republic of China died 2 days after their arrival at a pet shop. They had neurological signs associated with generalized toxoplasmosis involving brain, lungs, liver, and the heart. Toxoplasma gondii-like tachyzoites and tissue cysts were found in organs of all four squirrels. The protozoa stained positively with T. gondii polyclonal antibodies and were ultrastructurally similar to T. gondii. Calodium (Capillaria) hepaticum infection was found in the liver of one squirrel. 相似文献
995.
Campos-Sánchez Jose Carlos Mayor-Lafuente Javier Guardiola Francisco A. Esteban María Ángeles 《Fish physiology and biochemistry》2021,47(5):1623-1643
Fish Physiology and Biochemistry - Inflammation is one of the main causes of loss of homeostasis at both the systemic and molecular levels. The aim of this study was to investigate in silico the... 相似文献
996.
Castro Liliane Araújo Andrade-Porto Sanny Maria Oliveira Rebeca Guimarães Batista Yasmin Luzeiro Silva Felipe Moura Araújo Oliveira Christiane Patrícia Feitosa Affonso Elizabeth Gusmão Cruz Claudinei Tavares-Dias Marcos 《Aquaculture International》2021,29(6):2477-2488
Aquaculture International - This study investigated the efficacy of trichlorfon against Neoechinorhynchus buttnerae, as well as its palatability, residue analysis, and the blood parameters of... 相似文献
997.
Luis García Esteban Paloma de Palacios Francisco García Fernández Juan Antonio Martín Mar Génova Juan Ignacio Fernández-Golfín 《Wood Science and Technology》2009,43(7-8):679-690
The hygroscopicity and thermodynamic properties of buried juvenile Pinus sylvestris L. wood with an age of 1,170 ± 40 BP were compared with the corresponding values of juvenile wood of the same species from recently cut trees. The 35 and 50°C isotherms were plotted following the saturated salts method and subsequently fitted in accordance with the GAB model. The isotherms were then compared by means of the hysteresis coefficients. X-ray diffractograms were used to analyse the crystal structure of the cellulose. The effect of time on the buried wood caused hemicelluloses degradation and a decrease in the crystallinity index and the crystallite length, resulting in an increase in the proportion of amorphous zones. Because of this, the equilibrium moisture contents of the buried wood are higher than of the recent wood, both in adsorption and desorption. In terms of the thermodynamic properties, the heat involved is greater in the buried wood than in the recent wood. 相似文献
998.
José Alfonso Domínguez Núñez Rosa Planelles González José Antonio Rodríguez Barreal José Antonio Saiz de Omeñaca González 《Agroforestry Systems》2009,75(3):251-259
Mycorrhizal and non-mycorrhizal holm oak (Quercus ilex L.) seedlings inoculated with black truffle (Tuber melanosporum) were grown under nursery conditions and subjected to drought hardening for 4 months in autumn and winter followed by irrigation
for 10 days. Leaf water potential and stomatal conductance were monitored during the 4 months of drought. When the test was
completed (March), measurements were made for each treatment (inoculated or non-inoculated), and watering regime (watered
and water-stressed). Pressure–volume curves, osmotic potential at full turgor, osmotic potential at zero turgor and the tissue
modulus of elasticity near full turgor were calculated. Mycorrhizal colonization and growth, and the content of the main mineral
nutrients N, P, K, Ca and Mg were measured. Water stress affected plant growth, caused an elastic adjustment of the plant
tissues, and decreased the P and K content, and inoculation improved the nitrogen content. Drought acclimation apparently
achieved the goal of improving the drought tolerance of holm oak seedlings, without depressing ectomycorrhizal root colonization
by T. melanosporum.
José Antonio Rodríguez Barreal—Deceased 相似文献
999.
Narcisa Urgiles Paúl Loján Nikolay Aguirre Helmut Blaschke Sven Günter Bernd Stimm Ingrid Kottke 《New Forests》2009,38(3):229-239
Most tree species in tropical mountain rain forests are naturally associated with arbuscular mycorrhizal fungi. Previous studies
in southern Ecuador of 115 tree species revealed that only three species were not associated with arbuscular mycorrhizal fungi.
Seedlings of tropical tree species raised in the nursery may need to be associated with arbuscular mycorrhizal fungi to survive
transplantation shock in higher numbers. Methods for establishing plantations with native tree species are not yet established
for Ecuador. Thus, we investigated the feasibility of using mycorrhizal roots of seedlings of Inga acreana, Tabebuia chrysantha, Cedrela montana and Heliocarpus americanus that had trapped mycorrhizal fungi from forest humus in the nursery to inoculate C. montana and H. americanus with native arbuscular mycorrhizal fungi. Inoculation with either a mixture of mycorrhizal roots from the four species or
only with mycorrhizal roots from the same tree species were compared with effects of moderate fertilization. Assessment of
plant growth and mycorrhizal status of 6-months-old Cedrela montana and Heliocarpus americanus revealed an improvement in growth and diverse associated fungi through mycorrhizal root inoculation in comparison with moderate
fertilization. Moderate fertilization did not suppress mycorrhization. 相似文献
1000.
A new spectrophotometric assay for the quantification of polyphenolic content has been validated. It is based on Prussian Blue method and adapted to microplate spectrophotometry. Prussian Blue reaction is critically dependent on reaction time, but microplate spectrophotometry permits exact measures of many samples at the same time. This new method is precise, reproducible, repeatable and exact. 相似文献