Soybean cultivar performance in the presence of soybean Asian rust,in relation to chemical control programs     

Junia Vianna Corrêa da Silva  Fernando César Juliatti  João Renato Vaz da Silva  Fernanda Carvalho Barros 《European journal of plant pathology / European Foundation for Plant Pathology》2011,131(3):409-418

Soybean rust is caused by an obligate parasite (Phakopsora pachyrhizi) which has spread in Brazil in each new season since 2001 and, despite the efforts to control the disease, losses have occurred every year. Its control demands several tactics amongst which chemical control with fungicides is the main method and remains indispensable. Control strategies such as the use of cultivars with partial resistance are desirable, but are not yet commercially available. The present study analyzed the existing differences in the reactions of short, medium and long cycle soybean cultivars against Asian rust and their responses to fungicide sprays. The experiment was conducted at Uberlandia-MG, Brazil, under field conditions from December 2007 to May 2008, in the Syngenta Seeds Experimental Station. The high pressure of the disease in the experiment simulated the natural pressure that the disease often reaches in Brazil. The studied variables were: visual severity (percentage of infected leaf area), percentage defoliation and productivity (kg ha⁻¹). Disease severity was expressed as AUDPC (area under disease progress curve). Variance analysis and comparison of means by the Tukey test (5% significance) were done for all variables studied. Significant differences were observed between cultivar effects and chemical control programs. The results obtained here indicate that the cultivars M-Soy 8199RR and Emgopa 315RR were less susceptible to disease, and that a control program termed “monitoring” (in which the appearance of new pustules of the pathogen were monitored to make the decision at each fungicide spray) was the most effective.  相似文献   

Chemical characterization and biological effects of Sicilian Opuntia ficus indica (L.) mill. Fruit juice: antioxidant and antiulcerogenic activity     

Galati EM  Mondello MR  Giuffrida D  Dugo G  Miceli N  Pergolizzi S  Taviano MF 《Journal of agricultural and food chemistry》2003,51(17):4903-4908

The juice of whole fruits of Sicilian cultivars of prickly pear (Opuntia ficus indica (L.) Mill.) was investigated, and the contents of ascorbic acid, total polyphenols, and flavonoids were determined. In the juice, ferulic acid was the chief derivative of hydroxycinnamic acid and the mean concentration of total phenolic compounds was 746 microg/mL. The flavonoid fraction, analyzed by high-performance liquid chromatography-diode array detection, consisted of rutin and isorhamnetin derivatives. The juice showed antioxidant activity in the DPPH(*) test, probably due to the phenolic compounds that are effective radical scavengers. The preventive administration of the juice inhibited the ulcerogenic activity of ethanol in rat. Light microscopy observations showed an increase in mucus production and the restoration of the normal mucosal architecture. The juice is nutritionally interesting, and its dietary intake could provide protection against oxidative damage.  相似文献   

Determination of anthocyanins from camu-camu (Myrciaria dubia) by HPLC-PDA, HPLC-MS, and NMR     

Zanatta CF  Cuevas E  Bobbio FO  Winterhalter P  Mercadante AZ 《Journal of agricultural and food chemistry》2005,53(24):9531-9535

Camu-camu [Myrciaria dubia (HBK) McVaugh] is a small fruit native to the Amazonian rain forest. Its anthocyanin profile has now been investigated for the first time. Fruits from two different regions of the S?o Paulo state, Brazil, were analyzed. The major anthocyanins were isolated by high-speed countercurrent chromatography. HPLC-PDA, HPLC-MS/MS, and 1H NMR were used to confirm the identity of the main anthocyanins of camu-camu. Cyanidin-3-glucoside was identified as the major pigment in the fruits from both regions, representing 89.5% in the fruits produced in Iguape and 88.0% in those from Mirandópolis, followed by the delphinidin-3-glucoside, ranging between 4.2 and 5.1%, respectively. Higher total anthocyanin contents were detected in the fruits from Iguape (54.0 +/- 25.9 mg/100 g) compared to those from Mirandópolis (30.3 +/- 6.8 mg/100 g), most likely because of the lower temperatures in the Iguape region.  相似文献   

Tritrichomonas foetus: a scanning electron microscopy study of erythrocyte adhesion associated with hemolytic activity     

De Carli GA  Tasca T  Pires Borges F 《Veterinary research》2004,35(1):123-130

The in vitro hemolytic activity of Tritrichomonas foetus was investigated. The parasite was tested against human erythrocytes of groups A, B, AB, and O, and against erythrocytes of nine adult animals of different species (the rabbit, rat, chicken, cat, dog, swine, horse, bovine, and sheep). The results showed that T. foetus strains (ATCC KV1, K, PAL, 5022, RJ, 90) did not present any hemolytic activity against any human erythrocyte group nor against rabbit, rat, chicken, cat, dog and swine erythrocytes. T. foetus strains, however, lysed horse, bovine, and sheep erythrocytes. No hemolysin released by the parasites could be identified. Hemolysis did not occur with trichomonad culture supernatants, with sonicated extracts of T. foetus, nor with killed organisms. Scanning electron microscopy (SEM) showed that human erythrocytes did not adhere to the trophozoites, in contrast horse erythrocytes adhered to the surface of the parasites and were phagocytosed for up to 90 min. The parasites are able to exert their cytopathic effects through: (a) physical contact established between the two cell surfaces, (b) toxins released from parasites into the interaction media, or (c) the association of both mechanisms. Further studies are necessary to clarify the importance of the hemolytic activity in the biology of T. foetus.  相似文献   

Update on the role of innate immune receptors during Brucella abortus infection     

Oliveira SC  de Almeida LA  Carvalho NB  Oliveira FS  Lacerda TL 《Veterinary immunology and immunopathology》2012,148(1-2):129-135

The innate immune system constitutes an efficient defense mechanism against invading microbial pathogens. Recent studies have revealed the intracellular signaling cascades involved in the TLR-initiated immune response to Brucella spp. infection. However, there is a piece of the puzzle missing that is the role of non-TLR receptors in innate immunity. The involvement of TLR receptors in brucellosis has been investigated by different research groups. It was demonstrated that TLR2 clearly does not play any role in controlling Brucella abortus infection in vivo, whereas TLR9 has been shown to be required for clearance of this bacterium in infected mice. The participation of adaptor molecules, such as MyD88 and TRIF has also been discussed. Recently, we and others have reported the critical role of MyD88- and not TRIF-mediated signaling in dendritic cell maturation and in vivo resistance during B. abortus infection. However, the relationship between specific Brucella molecules and non-TLR receptors and signal transduction pathways needs to be better understood. It is now clear that the interaction between TLRs and recently identified cytosolic innate immune sensors is crucial for mounting effective immune responses. Finally, this review discusses the mechanisms used by Brucella to escape detection by the host innate immune system.  相似文献   

Mammary invasive micropapillary carcinoma in a male cat: Immunohistochemical description and clinical follow-up     

Gregório H  Pires I  Seixas F  Queiroga F 《Acta veterinaria Hungarica》2012,60(2):257-261

We describe the case of a 14-year-old Domestic Short Hair male cat that presented with a single mammary tumour one centimetre in diameter, classified as invasive micropapillary carcinoma. Histology and immunohistochemistry revealed a high mitotic index, a KI-67 index of 10%, a lack of reactivity to myoepithelial markers, and a dense infiltration with T and B lymphocytes at the periphery of the tumour. Micrometastases were detected in the regional lymph node at the time of surgery. Overall survival time was 10 months with a disease-free interval of 7.5 months. Distant metastases in the sublumbar lymph nodes confirmed the aggressiveness of this tumour, which has recently been subtyped in female cats. This is the first case reported in male cats with a complete follow-up, highlighting the importance of prompt and aggressive treatment in the presence of mammary tumours in male cats.  相似文献   

Variants of the recently discovered avian gyrovirus 2 are detected in Southern Brazil and The Netherlands     

dos Santos HF  Knak MB  de Castro FL  Slongo J  Ritterbusch GA  Klein TA  Esteves PA  Silva AD  Trevisol IM  Claassen EA  Cornelissen LA  Lovato M  Franco AC  Roehe PM  Rijsewijk FA 《Veterinary microbiology》2012,155(2-4):230-236

A genome of a virus preliminarily named avian gyrovirus 2 (AGV2), a close relative to chicken anemia virus, was recently discovered in a chicken in the state of Rio Grande do Sul, Southern Brazil. To study the occurrence of AGV2 in Rio Grande do Sul and the neighboring state Santa Catarina, a number of adult chickens (n=108 and n=48, respectively) were tested for the presence of AGV2 DNA. An AGV2-specific PCR was developed, optimized and used to analyze DNA extracted from clinical samples. AGV2 DNA was detected in 98/108 (90.7%) of samples collected in the state of Rio Grande do Sul and 29/48 (60.4%) of the samples collected in the state of Santa Catarina. In order to check whether AGV2 DNA would be detected in samples from a geographically distant region, DNA from brain samples of 21 diseased chickens from the Netherlands were tested independently, by the same method. In such specimens, 9/21 (42.9%) brain tissue samples were found to contain AVG2 DNA. Sequence analysis of some of the PCR products demonstrated that the amplified AGV2 sequences could vary up to 15.8% and could preliminarily be divided in three groups. This indicated the occurrence of variants of AGV2, which may reflect differences in geographical origin and/or in biological properties. The data presented here provides evidence that AGV2 seems fairly distributed in chickens in Southern Brazil and that AGV2 also circulates in the Netherlands. Besides, circulating viruses display genetic variants whose significance should be further examined, particularly to determine whether AGV2 would play any role in chicken diseases.  相似文献   

Cecotrophy behavior and use of urea as non-protein nitrogen (NPN) source for capybara (Hydrochoerus hydrochaeris)     

Sérgio Luiz Gama Nogueira-Filho  Alcester Mendes  Ellis Fernanda Kowalski Tavares  Selene Siqueira da Cunha Nogueira 《Tropical animal health and production》2013,45(8):1703-1708

Fifteen female adult capybaras, with initial average body weight (BW) of 32.7 (±?5.8) kg, were kept in individual pens to evaluate effect of supplementation of concentrate feed and its supply time on cecotrophy behavior frequency. The animals were allocated in a completely randomized design, with five animals per treatment, receiving three diets: grass only, grass and grain corn offered in a single meal, and grass and grain corn offered in two daily meals; all cecotrophy acts were recorded. Later, in a second experiment, five capybaras received five levels of urea in their diet: 0, 10, 20, 30, and 40 g urea/100 kg BW, replacing soybean meal as true protein source, in a 5?×?5 Latin square design. The animals were weighed and their blood was collected every 2 weeks. The frequency of cecotrophy (Ps?<?0.05) was higher when the capybaras were fed grass only (0.5?±?0.07 acts/h) than when they received grass and corn in a single meal (0.3?±?0.05 acts/h) and grass and corn supplied in separate meals (0.1?±?0.03 acts/h). With increased urea in their diet, the capybaras showed initial signs of chronic intoxication, together with increments in serum urea (r?=?0.87, P?<?0.05) and a decreasing trend in daily weight gain (r?=??0.38, P?=?0.06). Therefore, when including concentrate feeds in capybara diet, these must be mixed with roughage in a single meal to avoid high decrease in the frequency of cecotrophy behavior and increase in dry matter intake. The replacement of soybean meal with urea in capybara diet is not recommended.  相似文献   

Multivariate approach for young bull selection from a performance test using multiple traits of economic importance     

Fernando Brito Lopes  Cláudio Ulhôa Magnabosco  Mariana Márcia Mamede  Marcelo Corrêa da Silva  Eliane Sayuri Myiage  Fernanda Paulini  Raysildo Barbosa Lôbo 《Tropical animal health and production》2013,45(6):1375-1381

This study used multivariate statistics to identify clusters of animals with similar expected progeny difference (EPD) and also identify leading traits that discriminate between bulls. Various linear selection indices based on specific selection criteria were proposed. Records were collected from 880 young Nelore bulls submitted to performance testing in central Brazil between 2001 and 2012. Pre-weaning average daily gain and weights at 210 days with direct and maternal effects were used in the analysis, in addition to post-weaning weight, scrotal circumference at 365 and 450 days, carcass finish and rib eye area. EPDs were classified into three groups, and the EPD means of two of these groups stood out and were considered important based on principal component analysis that associated higher values of direct EPD of weights, average daily weight gain and scrotal circumference. The EPDs for weight at 210, 365 and 450 days, pre- and post-weaning daily gain and scrotal circumference at 365 and 450 days were major causes of variation. Each linear selection index proposed (SI₁, SI₂, SI₃, SI₄ and SI₅) defined a specific approach meaning that a different selection index should be used depending on breeding goals and selection criteria.  相似文献   

Productivity and nutritive value of Brachiaria decumbens and performance of dairy heifers in a long‐term silvopastoral system     

Marina A. Lima  Domingos S. C. Paciullo  Mirton J. F. Morenz  Carlos A. M. Gomide  Renato A. R. Rodrigues  Fernanda H. M. Chizzotti 《Grass and Forage Science》2019,74(1):160-170

Silvopastoral system (SPS) has been suggested to ensure sustainability in animal production systems in tropical ecosystems. The objective of this study was to evaluate the productive and nutritive value traits of Brachiaria decumbens and performance of dairy heifers in SPS and open pasture (OP) during the summer and autumn of two consecutive years in the SPS and OP (17th and 18th years after establishment). Experimental design was a randomized complete block with two treatments (SPS and OP) and three replications in subdivided plots with repeated measures in time. There was reduction in the tiller population density, total and green forage mass, and total and green forage bulk density in the SPS when compared to the OP in the summer. In the autumn, no difference was observed between the systems. Shading in SPS increased crude protein content of the grass pasture by 25% and 33% when compared to the OP during the first and second experimental years, respectively, and reduced neutral detergent fibre content. However, it did not change acid detergent fibre or lignin content. OP provided higher stocking rate and weight gain per area than the SPS. Average daily gain was higher in the OP in the second experimental year. Severe shading conditions should be avoided, because in the long ‐ term they may threaten the persistence and sustainability of pasture in the SPS. It is recommended to plant a low density of trees or implement management strategies of the tree component by either thinning or pruning over the years after planting.  相似文献