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排序方式: 共有1112条查询结果,搜索用时 15 毫秒
941.
Ferreira SR de Araújo JV Braga FR Araujo JM Fernandes FM 《Tropical animal health and production》2011,43(8):1589-1593
One isolate of predator fungi Duddingtonia flagrans (AC001) was assessed in vitro regarding the capacity of supporting the passage through pigs' gastrointestinal tract without
loss of the ability of preying infective larvae Oesophagostomum spp. Fungal isolates survived the passage and were efficient in preying L3 since the first 8 h of collection (p < 0.01) in relation to the control group (without fungus). Compared with control, there was a significant decrease (p < 0.01) of 59.6% (8 h), 71.7% (12 h), 76.8% (24 h), 81.0% (36 h), 78.0% (48 h), 76.1% (72 h), and 82.7% (96 h) in means of
infective larvae Oesophagostomum spp. recovered from treatments with isolate AC001. Linear regression coefficients of L3 of recovered Oesophagostomum spp. regarding the collections due to time were −0.621 for control, −1.40 for AC001, and −2.64 for NF34. Fungi D. flagrans (AC001) had demonstrated to be promising for use in the biological control of pig parasite Oesophagostomum spp. 相似文献
942.
Mauro L.S. Machado Laerte Ferreiro Rafael R. Ferreira Luis G. Corbellini Manjula Deville Madeleine Berthelemy Jacques Guillot 《Veterinary dermatology》2011,22(1):46-52
Skin carriage and quantification of Malassezia yeasts were evaluated in 180 healthy dogs (group 1) and 117 dogs with clinical signs (pruritus, erythema, lichenification/seborrhoea, excoriations and alopecia) that could be related to Malassezia dermatitis (group 2) in Brazil. The lesions in the group 2 dogs were evaluated using CADESI‐03 scores. Samples were collected from five different anatomical areas. Direct examination was performed using the tape strip technique, and results were expressed as the mean number of yeasts per ×1000 microscopic field per dog. For mycological culture, a single piece of sterilized carpet was applied to the same areas sampled for cytology, and transferred onto Dixon’s modified medium. Yeast populations were expressed as mean colony forming units (CFU)/plate. Malassezia isolates were characterized by polymerase chain reaction–restriction endonuclease analysis of the large subunit (LSU) of ribosomal RNA gene. The probability of culturing Malassezia from dogs with skin lesions was significantly higher (P < 0.001) than from healthy dogs. There was a linear trend between CADESI‐03 score and mean CFU/plate. Group 2 dogs with positive cultures had higher CADESI‐03 scores than those with negative cultures (P < 0.05). Almost all isolates were identified as Malassezia pachydermatis. Only one isolate (group 2) was identified as Malassezia furfur. These data suggest that dogs with skin disorders harbouring Malassezia yeasts in quantities higher than 120 mean CFU/plate should be considered as having Malassezia dermatitis. The presence of Malassezia appears to exacerbate clinical lesions in dogs. 相似文献
943.
Géssica Mylena Santana Rêgo Iêda Alana Leite de Souza Gabrielle Avelar Silva Mara Elisa Soares de Oliveira Maria Alves Ferreira 《Forest Pathology》2023,53(2):e12803
Fungi of the Cryphonectriaceae family are globally known to be tree pathogens. In Brazil, several species of Chrysoporthe have been found causing stem and branch cankers in Pleroma (= Tibouchina) spp. Recently, Chrysoporthe puriensis was described as a new species causing stem and branch cankers in Pleroma granulosum, Pleroma candolleanum, and Pleroma heteromallum, all native species of the Melastomataceae family. During an investigation to collect isolates of the Cryphonectriaceae family in an important Brazilian biome, the Atlantic Forest, in Serra do Mar, structures typical of Chrysoporthe species were found in a different host, Pleroma mutabile. Fruiting bodies present in the bark of these trees were collected and isolated. The isolates were submitted on morphological characterization and phylogenetic analyses of the internal transcribed spacer (ITS) and β-tubulin gene regions using Maximum likelihood, Bayesian inference and Maximum parsimony methods. The isolates collected, for this study, were identified as C. puriensis. Pathogenicity tests on seedlings of Pleroma species and Eucalyptus clones revealed C. puriensis can infect and cause canker in these plant species as mortality. The results demonstrate the importance of delimiting the C. puriensis collection range to track its dissemination in other hosts. No host specificity was observed in the inoculation tests, suggesting this is an important finding, the pathogen causes diseases and mortality in several plants of the Atlantic Forest. Additionally, the pathogen can affect others hosts, such as Eucalyptus clones in commercial plantations. 相似文献
944.
945.
Ana Cecília Machado Cruvinel Matheus Camargos de Britto Rosa Bruna Lívia Lopes Guimares Cecília Ferreira Amaral Silva Paulo Henrique de Sampaio da Silva Cesar de Lima Borges Leo Juliano V. Peixoto Joo Chrysostomo de Resende Júnior Antonio Carlos Cunha Lacreta Junior Marcelo Passamani Andr Rodrigues da Cunha Barreto‐Vianna Eduardo M. M. de Lima Gregrio Corrêa Guimares 《Anatomia, histologia, embryologia》2019,48(3):256-263
946.
Sorption and leaching potential of herbicides on Brazilian soils 总被引:1,自引:0,他引:1
Sorption of the herbicides alachlor, atrazine, dicamba, hexazinone, imazethapyr, metsulfuron-methyl, nicosulfuron, simazine and sulfometuron-methyl was characterized on six Brazilian soils, using the batch equilibration method. In general, weak acid herbicides (dicamba, imazethapyr, metsulfuron-methyl, nicosulfuron and sulfometuron-methyl) were the least sorbed, whereas weak bases such as triazines and nonionic herbicides (alachlor) were the most sorbed. The Kd values found showed a significant correlation with soil organic carbon content (OC) for all herbicides except imazethapyr and nicosulfuron. Koc values showed a smaller variation among soils than Kd . To estimate the leaching potential, Koc and the ground-water ubiquity score (GUS) were used to calculate half-lives ( t1/2 ) that would rank these herbicides as leachers or non-leachers. Comparison of calculated values to published values for t1/2 demonstrated that sulfonylureas and hexazinone are leachers in all soils, alachlor is transitional, and atrazine, simazine and dicamba are leachers or transitional, depending on soil type. Results discussed in this paper provide background to prioritize herbicides or chemical groups that should be evaluated in field conditions with regard to their leaching potential to ground-water in tropical soils. 相似文献
947.
Maria Joo A. Magalhes Júlia R. Ferreira Lúcia Frutuoso Antnio A. Taínha 《Pest management science》1989,27(1):23-31
The influence of surface of exposure of brassicas to insecticide sprays has been assessed in two experiments conducted in small plots where endosulfan, parathion, trichlorfon and pirimicarb were applied to a flowering brassica, broccoli (Brassica oleracea L. var italica Plenck) and to a leafy brassica (Brassica oleracea L. var. tronchuda Bailey). The differences of surface exposure resulted in much higher deposits and subsequent residue levels in broccoli. The results stress the need to evaluate residue data on groups of brassicas of different surfaces of exposure to pesticide spray when granting registration petitions for brassicas in general in order to establish pre-harvest intervals. 相似文献
948.
Early hip laxity examination in predicting moderate and severe hip dysplasia in Estrela mountain dog
Ginja MM Gonzalo-Orden JM Melo-Pinto P Bulas-Cruz J Orden MA San Roman F Llorens-Pena MP Ferreira AJ 《The Journal of small animal practice》2008,49(12):641-646
Objectives : To determine the reliability of early passive hip laxity examination in predicting moderate and severe hip dysplasia. Methods : The passive hip laxity of 104 Estrela Mountain dogs was evaluated using the Ortolani method, conventional hip‐extended radiography and the PennHIP method, when the animals were between four and 12 months of age. After the age of one, dogs were re‐examined for hip dysplasia using the Fédération Cynologique Internationale scoring system. The passive hip laxity results were subsequently compared with the Fédération Cynologique Internationale scores for sensitivity, specificity, positive predictive value, negative predictive value and accuracy. Results : The PennHIP method achieved the best results in specificity (93 per cent), positive predictive value (91 per cent) and accuracy (88 per cent), and the Ortolani method was the best in sensitivity (92 per cent) and negative predictive value (92 per cent). Clinical Significance : The Fédération Cynologique Internationale grades D and E can be predicted with confidence even before animals are one year old. 相似文献
949.
1. The aim of this work was to evaluate the shelf life of turkey meat from different colour categories (Pale, Soft and Exudative (PSE)-like), intermediate and dark), packaged under aerobic or modified atmosphere (MAP) conditions; also to establish a relationship between microbial quality and total volatile basic nitrogen (TVB-N), evaluating its capacity for shelf life determination. 2. Breasts were selected according to luminance (L*) and pH(24): L >/= 51 and pH < 5.8 for light colour, 43 < L < 51 for intermediate colour, L = 43 and pH > 5.8 for dark colour. Sliced meat was packaged under aerobic or MAP conditions with 50% N(2) and 50% CO(2), then stored in the dark at 0 +/- 1 degrees C for periods of 12 or 25 d. Meat under aerobic conditions was evaluated for microbiological characteristics and TVB-N on d 0, 5 and 12. This evaluation was extended to include d 19 and 25 when samples were under MAP conditions. 3. The dark meat group after 12 d of storage in aerobiosis presented significantly higher plate counts of aerobic mesophilic, psychrotrophic micro-organisms and higher TVB-N than other meat colour categories. The shelf life of turkey meat under MAP was one week longer for intermediate and light colour meat (20 d) than for dark meat. TVB-N values of 20 to 30 mg NH(3)/100 g turkey meat correspond to advanced spoilage stages. We proposed 14 mg NH(3)/100 g as the limit of freshness acceptability for turkey meat. 4. TVB-N was an indicator of turkey meat microbial spoilage but was not a suitable early predictor for microbial spoilage and in particular for turkey meat stored under MAP conditions because counts of micro-organisms were moderately correlated (Pseudomonas spp. and Enterobacteriaceae) with this index, as they were inhibited by MAP gas mixture and storage temperature used in the present study. 相似文献
950.
Ferreira PG Dinís M Costa-E-Silva A Aguas AP 《Veterinary immunology and immunopathology》2008,121(3-4):364-369
Calicivirus infection of adult rabbits induces the so-called rabbit haemorrhagic disease (RHD) that kills 90% or more of the infected animals; in contrast, young rabbits (up to 8-week-old animals) are resistant to the same infectious agent. We report that calicivirus inoculation of young rabbits induced moderate titres of antiviral antibodies. When these rabbits reached adulthood, a second calicivirus inoculation resulted in resistance to RHD and boosting of antibody titres in half of the rabbits. Adoptive transfer of sera from calicivirus-infected young rabbits to na?ve adult rabbits conferred resistance to RHD. We conclude that calicivirus infection of young rabbits induces specific anti-calicivirus antibodies that will protect them from RHD when they reach adulthood. 相似文献