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41.
Rachel C. Pinho Sonia S. Alfaia Robert Pritchard Miller Katell Uguen Leovone D. Magalhães Marta Ayres Viviane Freitas Ralph Trancoso 《Agroforestry Systems》2011,81(3):235-247
Homegardens are a common feature of indigenous dwellings in the savannas of Roraima, northern Brazil. In order to evaluate the effect of homegardens on soils, samples were taken in 5 sites each in the categories new homegardens (0–10-years old), established homegardens (15–35-years old) and old homegardens (more than 40-years old) and in adjacent savanna in Araçá Indigenous Land, Roraima, Brazil. For comparison, samples were also taken in forest islands located nearby, on a different soil type, under 10-year-old forest fallows and high forest. P and K showed the greatest increases over time in homegarden soils, in comparison with levels found in adjacent savanna and under forest. Ca and Mg also increased in comparison to adjacent savanna, but levels were less than found in forest soils, most likely due to the different parent material. Zn and Fe also showed increases in homegarden soils over time. Cu and Mn levels showed little relation to homegarden age, suggesting greater effects of factors of soil formation than anthropogenic influences. Values for pH were slightly higher in homegardens than in adjacent savanna, while Al was lower, although these changes were poorly fit by regression models. Soil organic matter increased over time under homegardens, but still was lower than levels found under fallows and forest. Soil fertility improvement under indigenous homegardens can be attributed mainly to deposition of residues around dwellings, although further investigation is needed on the role of trees in accessing nutrient pools at greater depths in savanna soils. 相似文献
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Volopich S Benetka V Schwendenwein I Möstl K Sommerfeld-Stur I Nell B 《Veterinary ophthalmology》2005,8(1):25-32
Samples were collected from 36 cats with feline herpesvirus (FHV-1)-related ocular disease (conjunctivitis, epithelial or stromal keratitis, or corneal sequestration), and 17 cats without ocular changes. Corneoconjunctival swabs, scrapings and biopsies were tested in various combinations for presence of FHV-1 DNA using single round (sr) polymerase chain reaction (PCR) and nested PCR (nPCR). Additional swabs from the inferior conjunctival fornix were tested by enzyme-linked immunosorbent assay for Chlamydophila felis antigen. Cytologic evaluation was carried out on conjunctival (cats with conjunctivitis) and corneal (cats with keratitis) cytobrush preparations. FHV-1 DNA was detected by PCR in 14 (39%) cats with ocular disease and 1 (6%) of the control group. Agreement between srPCR and nPCR results was significant (P < 0.01). FHV-1 DNA was detected in 3/7 cats with conjunctivitis, 5/6 cats with epithelial keratitis, 3/11 cats with stromal keratitis, and 3/12 cats with corneal sequestration. There was a significant association (P = 0.0027) between viral presence and epithelial keratitis. However, no significant association was found between viral presence and conjunctivitis (P = 0.059), stromal keratitis (P = 0.15), or corneal sequestration (P = 0.18). With respect to FHV-1 DNA detection, intersample agreement was significant (P < 0.03). No sampling technique seemed more likely than another to harvest detectable viral DNA, except for cats with corneal sequestrum in which viral DNA was not detected using corneoconjunctival swabs. FHV-1 DNA was detected in 6/9 samples with intranuclear inclusion bodies and in 6/7 cats with eosinophils on cytologic examination. All samples tested negative for C. felis antigen. 相似文献
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Lucas Machado Figueira Nadja Gomes Alves Ribrio Ivan Tavares Pereira Batista Viviane Lopes Brair Renato Ribeiro Lima Maria Emilia Franco Oliveira Jeferson Ferreira Fonseca Joanna Maria Gonalves Souza‐Fabjan 《Reproduction in domestic animals》2019,54(11):1493-1496
This study investigated the feasibility of applying fixed‐time (cryopreserved) embryo transfer in ewes. Embryos (n = 106) were non‐surgically recovered from superovulated donors (n = 39) on day 6–7 after oestrus. Straws containing one or two embryos (morulae and/or blastocysts) subjected to either slow freezing (SF, n = 62) or vitrification (VT, n = 44) were randomly used within fixed‐time embryo transfer on Day 8.5. Recipient ewes were nulliparous (n = 58) bearing corpora lutea after synchronous oestrous induction protocol. The pregnancy rate was higher (p = .03) in SF (39.4%) than VT (16.9%) and survival rate tended (p = .08) to be higher in SF than in VT (25.8% vs. 15.9%). Lambing rates were similar (p = .13) between SF (20.9%) and VT (15.9%). Embryos recovered by non‐surgical route after cervical dilation treatment and later cryopreserved by either slow freezing or vitrification produced reasonable pregnancy rates after FTET. 相似文献
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Szabó MP Castro MB Ramos HG Garcia MV Castagnolli KC Pinter A Veronez VA Magalhães GM Duarte JM Labruna MB 《Veterinary parasitology》2007,143(2):147-154
This study evaluated the presence and seasonal activity of free-living ticks in remaining marsh areas by the Paraná river, in Brazil. Eight field trips (once per season) for collection of ticks were performed during 2 years. Using CO2 traps, dragging, and visual inspection of vegetation, five free-living tick species were collected, in the following order of abundance: Amblyomma cajennense, Amblyomma dubitatum, Amblyomma triste, Amblyomma coelebs, and Amblyomma nodosum. The seasonal pattern of A. cajennense was characterized by the highest peaks for adult ticks in the summer/spring months, for nymphs in the winter and for larvae in the autumn and winter. A. dubitatum and A. triste presented similar seasonal patterns characterized by peaks of adult ticks in the autumn. Nymphs of A. dubitatum peaked in the winter of the first year and in the winter/spring of the second year. A. triste was the only species to be collected in significantly higher numbers in the marsh than in surrounding drier areas such as forest patches. Among domestic animals living close the marsh areas, horses were infested by Anocentor nitens, A. cajennense, and Boophilus microplus, bovines were infested solely by B. microplus, and dogs were infested by Rhipicephalus sanguineus. Adults of A. triste showed to be well adapted to the marsh environment. This result, at least partially, explains local previous observations on the association of A. triste with marsh deer, as this vertebrate host inhabits mainly the marsh area. 相似文献
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Gabriela Almeida Bastos Leydiana Duarte Fonseca Adriano Vinícius de Paiva Ferreira Marco Aurélio Morais Soares Costa Maria Luiza França Silva Viviane de Oliveira Vasconcelos Rogério Marcos de Sousa Eduardo Robson Duarte 《Tropical animal health and production》2017,49(5):937-943
In this study the helminthiasis and anthelmintic effectiveness in ewes and lambs were evaluated in a semiarid region of Brazil. Twelve sheep farms were investigated using semi-structured questionnaires and fecal egg count (FEC) reduction test was employed to analyze the profile of anthelmintic resistance. Groups of at least 10 animals with FEC ≥ 300 were selected. After 12 h of fasting, homogeneous groups of lambs or ewes were treated with albendazole, levamisole moxidectin, or oxfendazole and control groups were not treated. Feces were collected before treatments and 14 days after, and larvae genera were identified after cuprocultures in both periods. Extensive grazing was the predominant creation system, using hybrid Santa Ines animals. The separation by age was promoted in 75% of herds; however, maternity pickets there were only in three farms. The strategic treatments were performed only in 8.4% of sheep farms and 16.6% used the anthelmintic efficacy test and alternated anthelmintic classes after 1 year. The initial FEC means for lambs were significantly higher than ewe FEC averages. For lamb tests, moxidectin and levamisole showed higher efficacy (p ≤ 0.05) than benzimidazoles. For ewe tests, moxidectin and levamisole showed efficiencies >75%. Haemonchus spp. and Trichostrongylus spp. were the most frequent nematodes before treatments and the genus Haemonchus was the most prevalent after anthelmintic treatments (p < 0.05). Variations of anthelmintic susceptibility were observed for categories and herds evaluated, which emphasizes the importance of the effectiveness tests for the choice of anthelmintics for ewes and lambs. 相似文献
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A study was carried out on the gut contents of mugilids, 4.27–22.88 mm total length, to find their food preferences in the natural environment. This information would aid in the feeding of young grey mullets obtained from induced reproduction.Samples were obtained from monthly cruises to five stations in the Haifa Bay area, located over depths from 5–25 fathoms (8–45 m). Neuston net, vertical and horizontal plankton net hauls were carried out, at each station. Variations of the common organisms in the plankton and the food components found in the digestive tracts of various size-groups of the grey mullets are tabulated.Copepods were found to be the most important food item in the gut contents, at all times of the year and at all sizes of mullets taken in the neuston. It appears that the smaller-sized fish feed on the smaller copepods, while the larger-sized fish feed on a wider range of sizes and species of Copepoda, although size of the prey was not the only factor influencing selection.No relationship was found between the availability in the plankton of the species, of a size that could be swallowed by the young mullets, and their proportion in the gut contents. This indicates that these fish are selective in their feeding in the natural environment. It was found that the preferences change with the size-group of mugilids. 相似文献
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Alan Rodrigues Teixeira Machado Viviane Aparecida Costa Campos Willian José Rodrigues da Silva Vicente Paulo Campos Ana Carolina de Mattos Zeri Denilson Ferreira Oliveira 《European journal of plant pathology / European Foundation for Plant Pathology》2012,134(2):431-441
To understand the effect of nematode Meloidogyne exigua infestation on coffee plants, resistant and susceptible coffee seedlings were inoculated with second-stage juveniles of M. exigua, and root metabolites were studied for four time intervals at 0, 24, 48 and 96 h. During this important period for parasite establishment, the concentrations of phenols, carbohydrates, amino acids and alkaloids in the roots were measured, and hydrogen nuclear magnetic resonance spectra of the root extracts were used to identify and quantify other metabolites. One of the most striking changes was the concentration of fumaric acid on resistant plants, which varied from 59 μg g(of root)?1 to 138 μg g(of root)?1 during the first 24 h of the nematode inoculation. The same level of variation was observed much later (96 h) in susceptible plants. Similarly, formic and quinic acid concentrations increased more rapidly in the resistant plants compared to the susceptibles. Sucrose concentrations increased to 370 % in the first 48 h in the resistant plants but showed no significant variation in the susceptible plant. Besides, the concentration of alkaloids was much higher at 24 and 48 h in the susceptibles compared to the resistant plants. These results suggest that the higher production of sucrose as well as formic, fumaric and quinic acids, and the lower production of alkaloids by the resistant cultivar in the first 48 h after the nematode inoculation are associated with the resistance of coffee plants to M. exigua. 相似文献
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Anne Chandelier Caroll Nimal Frédéric André Viviane Planchon Robert Oger 《European journal of plant pathology / European Foundation for Plant Pathology》2011,130(3):403-414
The occurrence of Fusarium species in winter wheat in southern Belgium (Wallonia) and the deoxynivalenol content in 692 samples collected in commercial
fields in the region’s main cereal growing area were investigated. The main Fusarium species associated with head blight in wheat were identified at levels that varied from year to year. Interactions between
fungal species causing head blight in wheat were detected, most of them positive. The years 2007 and 2008 were very conducive
to the disease and there was a strong correlation between mean annual deoxynivalenol content and number of days with a mean
relative humidity above 80% over a period starting from 7 days before the mean flowering date and ending 16 days after this
date. A two-stage approach, based on type of year (at risk or not) and agricultural practices during risk years has been developed
to help cereal storage companies reduce the risk of mixing sound and deoxynivalenol-contaminated lots at harvest and to limit
the number of analyses. 相似文献