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In this investigation, we determined the prevalence of the Ornithobacerium rhinotracheale (ORT) infection in broilers and broiler breeders in southern Brazil. We also correlated the presence of antibodies in broilers with performance. Sera from 1550 broilers from 50 flocks were collected during the slaughter time in nine companies with federal veterinary inspection of the state of Rio Grande do Sul. Sera from 480 meat-type breeders of 40 flocks from 14 companies in southern Brazil were also analyzed by enzyme-linked immunosorbent assay, and the prevalence of antibodies was determined. The prevalence of ORT antibodies in broiler flocks was 63.83%, but in each individual flock only 6.52% of the birds were positive. The prevalence in broiler breeder flocks was 100.00%, and in each individual flock 94.62% of the birds were positive. There was a positive correlation between the presence of antibodies to ORT and decreased body weight in broilers. There was no significant correlation between presence of antibodies to ORT and age, lineage, efficiency index, feed conversion, and mortality. There was a positive correlation between the presence of respiratory signs and antibodies to ORT, although the reverse correlation was not significant. These results confirm that ORT is present and widespread in broilers and broiler breeders in southern Brazil. 相似文献
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Characteristics and decomposition rates of pruning residues from a shaded coffee system in Southeastern Brazil 总被引：1，自引：0，他引：1
In the Zona da Mata Mineira of Southeastern Brazil the development of sustainable land requires the integration of crops with trees. The objectives of this study then were to (i) characterize prunings from the main tree species in an agroforestry system; (ii) determine the effects of the physical and chemical characteristics of the prunings on their decomposition patterns in the laboratory; (iii) assess the effect of mixing leaves of different species on decomposition rates; and (iv) propose a decomposition index for the residues studied. The study was carried out with pruning residues from Cajanus cajan, Solanum variable, Cassia ferruginea, Piptadenia gonoacantha, Croton urucurana, and Melinis multiflora. The materials were characterized for total C, N, P, Ca, Mg and K contents; lignin, cellulose, hemicellulose and soluble polyphenols contents. The pruning residues had high polyphenols and lignin contents, high C:N and C:P ratios, and low contents of Ca, Mg, and K. The low decomposition rates of the prunings were related to the P, K, hemicellulose and polyphenol contents. The rates of N mineralization from most of the residues indicate that there is a potential to supply the needs of a crop of maize. The residues of some species, if decomposed alone, would not supply sufficient nutrients, and need to be mixed with leaves of other species.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
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Helton Nonato de Souza Irene Maria Cardoso Eduardo de Sá Mendon?a An?r Fiorini Carvalho Gustavo Bediaga de Oliveira Davi Feital Gjorup Ver?nica Rocha Bonfim 《Agroforestry Systems》2012,85(2):247-262
Participatory research methods have helped scientists to understand how farmers experiment and to seek partnerships with farmers in developing technologies with enhanced relevance and adoption. This paper reports on the development of a participatory methodology to systematize long-term experimentation with agroforestry systems carried out in a hotspot of biodiversity by non-governmental organizations and local farmers. A methodological guide for systematization and techniques used for Participatory Rural Appraisal formed the basis of our work. We propose an analytical framework that recognizes systems of reflexive and learning interactions, in order to make the learned lessons explicit. At the process level, the main lessons and recommendations are as follows. It is important to establish partnerships to conduct innovative and complex experimentation with agroforest. Participatory systematization allows us to improve the methodological aspects of design, implementation and management of on-farm participatory experimentation. It also serves to synthesize the main findings and to extract lessons from agroforestry systems experiments. It fosters the technical improvement of agroforestry systems. It creates possibilities for reflection on agroforestry systems by farmers, extensionists and researchers, as well as their learning with respect to management of such systems. The findings are placed in the context of current theory on participatory experimentation in agriculture. Extractive and interactive approaches help to produce rich insights of mutual interest through collaboration by identifying local, regional and global convergences, complementarities, and conflicts of interest; which affect the advance of new eco-friendly technologies, to both improve the livelihoods and to reverse biodiversity loss and environmental degradation. 相似文献
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Effect of dietary lipid-lowering drugs upon plasma lipids and egg yolk cholesterol levels of laying hens. 总被引：3，自引：0，他引：3
To evaluate the effect of lipid-lowering agents upon egg quality, reproductive performance, plasma lipids, and egg yolk cholesterol levels, 30-week-old Shaver laying hens were fed a basal diet (commercial ration) supplemented with 0.1% probucol (PROB), 0.025% gemfibrozil (GEMF), or lovastatin at 0.0005% (LOV1), 0.001% (LOV2), or 0.0015% (LOV3) for a 12-week experimental period. It was observed that the supplementation of the drugs did not impair albumen and shell quality. Hen performance was not adversely affected. The depression in triglyceride concentrations approached statistical significance only in LOV2 (38.5%), and total cholesterol was significantly depressed in LOV2 (36.0%), LOV3 (36.8%), PROB (29.6%), and GEMF (30.4%) treatments. Egg cholesterol content, expressed per gram of yolk, was significant lowered in LOV1 (7.5%) and LOV3 (12. 7%). 相似文献
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Vinicius de Abreu D’Ávila Elen de Lima Aguiar-Menezes Renato Nunes Pereira Vânia Gonçalves-Esteves Cláudia Barbieri Ferreira Mendonça Saulo José de Melo Tamires Medeiros dos Santos 《Phytoparasitica》2017,45(4):471-484
Coleomegilla maculata DeGeer is an omnivorous lady beetle that feeds on natural or alternative prey and artificial foods, which allows its laboratory rearing for use on augmentative biocontrol. In addition, C. maculata may supplement its diet with pollen and nectar, which helps in its conservation in agroecosystems. This study aimed to evaluate if Apiaceous flowers (Anethum graveolens L. and Coriadrum sativum L.), with and without alternative prey [eggs of Ephestia kuehniella (Zeller) or larvae of Drosophila melanogaster Meigen] or an artificial food (aqueous solution of honey), may guarantee the survival and complete development of the immature and adult stages of C. maculata in the laboratory. The immature stages developed only when Apiaceous flowers were offered with E. kuehniella eggs. The food with only one of the alternative prey (moth eggs or fly larvae) or moth eggs + honey solution resulted in fertile adults; however, the number of eggs/cluster was greater for the foods with E. kuehniella eggs + honey solution, A. graveolens flowers, or only D. melanogaster. Foods comprising only the two Apiaceous species, only the honey solution, or only water resulted in larval development up to a specific instar. Adults of C. maculata also survived on these foods, but there was no oviposition. The foods of the two Apiaceous species produced heavier adults only when associated with E. kuehniella eggs. The results indicate that the zoophytophagous habit of C. maculata should be considered in conservation biocontrol programs aimed at using this lady beetle to control crop pests. 相似文献
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Net mineral requirements for growth of Saanen goat kids in early life are similar among genders 
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下载免费PDF全文 A. N. Mendonça C. J. Härter S. F. Souza D. Oliveira O. Boaventura Neto B. Biagioli K. T. Resende I. A. M. A. Teixeira 《Journal of animal physiology and animal nutrition》2017,101(1):113-120
The current mineral requirements for growing goat kids are based on sheep and cattle studies without differentiating between the stages of development or gender. The aims of this study were to determine the net requirements for growth of Ca, P, Mg, Na and K of Saanen goat kids during the initial stages of growth and to analyse the effect of gender on the net requirements for growth of these macrominerals. Eighteen female, 19 intact male and 10 castrated male Saanen goat kids were studied. The kids were selected applying a completely randomized design and slaughtered when their body weight (BW) reached approximately 5, 10 and 15 kg to determine the mineral requirements for growth at these stages. The net mineral requirements for growth were similar among genders. The goat kids had slightly increased net requirements of Ca, P and Mg for growth with increasing BW from 5 to 15 kg. The net requirements for growth of Ca, P, Mg, Na and K ranged from 9.61 to 9.67 g/kg of BW gain, 7.14 to 7.56 g/kg of BW gain, 0.34 to 0.37 g/kg of BW gain, 1.26 to 1.13 g/kg of BW gain, 1.88 to 1.82 g/kg of BW gain as the animals grew from 5 to 15 kg respectively. In conclusion, when formulating diets for Saanen goat kids in early growth stage mineral levels do not need to adjusted based on gender. 相似文献
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Fonseca BB Beletti ME Melo RT Mendonça EP Vieira CU Levenhagen MA Rossi DA 《British poultry science》2011,52(3):279-286
1. The objective of this study was to evaluate the ability of Campylobacter jejuni to penetrate and colonise eggs from specific-pathogen-free (SPF) and heavy breeder hens, and to determine its effects on the viability of SPF embryos.
2. We detected C. jejuni in 10% of breeder hens and 20% of SPF eggs, which demonstrates the ability of the bacteria to go through the pores of eggs and contaminate the vitellus after 3?h of contact. These results indicate that there is a risk of contamination under commercial production conditions, where, after oviposition, there is contact between the egg and organic material such as faeces and blood.
3. We observed that in 80% of SPF eggs analysed, C. jejuni survived the 21-d incubation period. This positive result suggests that this microorganism was also responsible for early embryonic mortality.
4. The ability of C. jejuni to penetrate the eggs in this study suggests that serious problems may occur under natural field conditions, which may cause significant problems for producers. 相似文献
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Almy Junior Cordeiro de Carvalho Patrícia Soares Furno Fontes Marta Simone Mendonça Freitas Pedro Henrique Monnerat Alexandre Gomes Fontes 《Journal of plant nutrition》2013,36(4):614-626
This work was performed in the Rio de Janeiro State, Brazil, with the objective to evaluate the nutritional status of yellow passion fruit plants along different phenological stages, using the DRIS method. Fifty-four passion fruit cultivated areas with an annual yield productivity ranging from 6.95 to 33.8 t ha?1 year?1 and average productivity of 16.9 t ha?1 year?1 were selected in the region. The contents of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), sulfur (S), chlorine (Cl), iron (Fe), zinc (Zn), manganese (Mn), and boron (B) were evaluated. The reference standards were established (mean and variation coefficient) for the values of the nutrient concentration ratios, two by two, on samples from high yield productivity plantations and analyzed by the DRIS index of nutrients for the medium and low yield productivity areas. The established standards differed according with the phenological stage of the culture. In a general way, the mean content of the evaluated nutrients did not differed between the two productivity levels into each phonological stage. There was a difference for the Nutritional Limitation Order between different phenological stages of yellow passion fruit plants. The most negative DRIS indexes and the highest absolute values for the Average Nutritional Balance on yellow passion fruit plants in the region, were found for potassium in May, phosphorus in October and iron in January. 相似文献