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Manoel Eduardo da Silva Fabio Ribeiro Braga Luana Alcântara Borges Jair Mendes de Oliveira Walter dos Santos Lima Marcos Pezzi Guimarães Jackson Victor de Araújo 《Veterinary research communications》2014,38(2):101-106
Brazil has a herd of 212 million cattle and 171 million hectares of pastures that produce approximately 96 % of Brazilian beef. The Brazilian production system enables animal infection by endoparasites, which are considered one of the main obstacles for the development of this industry and are responsible for considerable economic losses. The control of parasitic diseases is performed via the administration of antiparasitic drugs, but they leave residues of the products in the treated animal, affect non-target organisms and select resistant strains of the parasites. The species D. flagrans and M. thaumasium are promising and sustainable alternatives for controlling gastrointestinal helminths of ruminants and other herbivores. In this study, we evaluated the efficacy of isolates of these species, formulated in a sodium alginate matrix and administered twice a week, to reduce the number of environmental infective larvae of gastrointestinal nematodes that affect prepubescent zebu females. The treated animals presented fewer eggs and a lower number of infective larvae per gram of faeces (p?<?0.05). The pastures occupied by treated animals showed a statistically significant reduction (p?<?0.05) of the number of L3 and, furthermore, the genera Cooperia sp., Haemonchus sp., and Oesophagostomum sp. were the most prevalent. The average weight of the animals did not differ statistically (p?>?0.05) among the treated and control groups. The use of sodium alginate pellets as vehicle for delivery of the fungus mycelia D. flagrans (isolate AC001) and M. thaumasium (isolate NF34A) proved effective in controlling trichostrongylids in prepubescent cows bred in the semi-arid region, with an effective reduction in the number of infective larvae in the pastures. 相似文献
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Vegetation structure of forest edges and type of adjacent field can affect seed and seedling survival patterns of tree species.
We investigated acorn removal and seedling survival of Quercus germana and Q. xalapensis in relation to woody plant density across old field-forest gradients with soft and abrupt edges. Experiments were established
along four parallel bands located at 40–50 m in the forest, forest and field edges (0–10 m to each side of the border), and
20–30 m in the old field. Within each band, woody plant and acorn density was measured, and four points for acorn and seedling
removal experiments were randomly positioned. In each position, 20 acorns or four seedlings were placed. Survival was monitored
during one month. In abrupt edges, acorn density was higher along edges than in forest interior. Also, higher acorn removal
and seedling mortality were observed in the adjacent old-field whereas acorn and seedling survival was the highest at the
edges. Acorn and seedling survival was positively correlated to woody vegetation density. As the vegetation density of field
and forest edges grows, abrupt edges develop into soft edges, and they become more hospitable to oak recruitment and then
to forest cover expansion. 相似文献
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Antinociceptive activity of the pyranocoumarin seselin in mice 总被引：1，自引：0，他引：1
Lima V Silva CB Mafezoli J Bezerra MM Moraes MO Mourão GS Silva JN Oliveira MC 《Fitoterapia》2006,77(7-8):574-578
Seselin an angular pyranocoumarin at dose of 0.5, 4.5 or 40.5 mg/kg inhibited the writhing response induced by acetic acid in a significant and dose-dependent manner, by 19.5%, 26.2% and 41.4%, respectively. Using the same doses, seselin elicited a significant inhibition of formalin response during the second phase (inflammatory), by 90.3%, 97.8% and 95.3%, respectively. Besides, a significant reduction of licking time was observed during the first phase (neurogenic) at the highest doses of seselin, by 34.4% and 66.9%, respectively. On the contrary, in the hot plate test no effect was observed after seselin treatment. In conclusion, seselin was able to inhibit inflammatory hyperalgesia, suggesting that this natural product possesses both important peripheral anti-inflammatory and antinociceptive properties. 相似文献
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Leal Murilo Henrique Souza Zeist André Ricardo Rodrigues Júnior Nilson Silva Júnior André Dutra Arantes José Henrique Verhalem Garcia Neto Jair de Pieri Julia Roberta Sanches Perrud Amanda Carvalho 《Journal of Crop Science and Biotechnology》2021,24(3):349-360
Journal of Crop Science and Biotechnology - Sweet potato (Ipomoea batatas L.) is a root that allows healthy eating and combats malnutrition. There is a need for more productive sweet potato... 相似文献
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Marcelo?C.?de?AlvesEmail author Fábio?M.?da?Silva Jair?Campos?Moraes Edson?A.?Pozza Marcelo?S.?de?Oliveira Júlio?C.?S.?Souza Luciana?S.?Alves 《Precision Agriculture》2011,12(1):18-31
The advent of geostatistics and geographical information systems has made it possible to analyze complex spatial patterns
of ecological phenomena over large areas in applied insect ecology and pest management. The objective of this study was to
use geostatistics to characterize the spatial structure and map the spatial variation of damage caused by the berry borer
(Hypothenemus hampei) and leaf miner (Leucoptera coffeella) in a coffee agroecosystem planted with the cultivar Catuai Vermelho IAC-99. Infestations of berry borer and leaf miner were
evaluated in fruits and leaves, respectively. The pests were monitored at 67 georeferenced points in an area of 6.6 ha in
2005, 2006 and 2007. Variograms estimated by the method of moments (MoM) and residual maximum likelihood REML were compared.
The latter were generally better in terms of the kriging error coefficients. Spherical variograms estimated by REML for berry
borer infestation in fruits had ranges of spatial dependence of 34.62–118.4 m and for the leaf miner they were 53.93–133.7 m.
For models fitted by weighted ordinary least squares (OLS) to the MoM experimental variogram, the ranges varied between 37.22
and 68.67 m for the berry borer and 100 and 155.4 m for leaf miner infestation. The variogram model parameters were used with
the data for ordinary kriging to map the spatial variation of coffee pests for different monitoring periods. If there was
no suitable variogram, inverse distance weighting was used to map the variation. The maps enabled visualization of the intensity
of infestation of the insect pests for the different periods evaluated. 相似文献
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Ana Cristina Curia Jair Carlos Koppe Jo?o F. C. L. Costa Liliana Amaral F��ris Wagner David Gerber 《Water, air, and soil pollution》2011,218(1-4):131-143
This paper presents the results of using a pilot-scale-constructed wetland as a tertiary system to simulate the treatment conditions of wastewater effluents from the metal-mechanical industry, aiming to achieve the Brazilian legal standards of phosphorus and nitrogen emission. The macrophytes were placed in 1 m3 polyethylene tanks, daily estimating the treatment of 2 m3 of effluents. The effluents were circulated in a horizontal subsurface flow through a porous matrix of thick sand and gravel, in which the roots of the macrophytes of the species Reed (Scirpus sp.) and Cattail (Typha sp.) were fixed. Monitoring of the pilot plant was performed through a battery of physical?Cchemical and biological analyses. Despite the load variations and operational problems, the system presented a positive degree of pollutant efficiency removal, especially for phosphorus (73% medium), TKN (61% medium), and NH4?CN (56% medium). Peak results were achieved during the last 3 months of monitoring. The chemical analysis of the support layer, plus the root system and aerial portion of the plants, revealed that these wastes could be used as fertilizer. 相似文献