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Characterization of blood flow and the effects of exogenous estradiol benzoate on residual follicles formed after ultrasound-guided transvaginal follicle aspiration in cattle

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Journal of Animal Science and Biotechnology 2017年第1期8卷 51-56页

作者： Alberto Mansur Ghetti Luiz Gustavo Bruno Siqueira Eduardo Kenji Nunes Arashiro Miller Pereira Palhao Felipe Zandonadi Brandao Joao Henrique Moreira Viana Universidade Federal Fluminense Niteroi RJ 24230-340 Brazil embrapa Gado de Leite Juiz de Fora MG 36038-330 Brazil Universidade Jose do Rosario Vellano Alfenas MG 37130-000 Brazil embrapa Recursos Geneticos e Biotecnologia PqEB Av. W5 N Brasilia DF 70770-917 Brazil

Background： Removal of the follicular content by ultrasound-guided transvaginal follicle aspiration（TVFA） may fail to induce immediate atresia and loss of function, resulting in the occurrence of residual follicles（RF）. The aims of this study were to characterize the blood flow in RF and to determine the effects of the treatment with estradiol benzoate on RF fate. Lactating, cyclic Holstein-Gir crossbred cows were used. In Experiment 1, follicular wave emergence（D0） was synchronized in cows（n = 10） and follicular growth was then monitored by transrectal ultrasonography from D0 to D8, followed by TVFA of the largest follicle present on the ovaries 24 h later. Color Doppler ultrasound imaging was used to examine blood flow on the follicular wall, which was recorded immediately before and every 12 h after TVFA, up to 72 h. In experiment 2, cows（n = 22） were randomly allocated to receive either 2 mL of saline i.m.（Control group, n = 11） or 2 mL estradiol benzoate i.m.（EB group, n = 11）immediately after TVFA. Ovaries were scanned every 12 h to confirm the presence and to measure the diameter of RF. The contents of the RF, if present, were collected 72 h after the first TVFA, using the same aspiration *** fluid from original follicles and RF were stored at-20 °C until hormonal ***： In Experiment 1, there was no reduction（P 〉 0.05） of blood flow in the remaining follicle walls after TVFA and maximum blood flow values were observed at 49.5 ± 19.7 h post-TVFA. In Experiment 2, formation of RF after TVFA was proportionally similar between Controls（5/9） and EB（5/10） cows. Also, RF diameter did not differ between groups（P 〉 0.05）. Nonetheless, the content of RF from cows in the EB group had lower（P = 0.0004）estradiol（E2） concentration and lower（P = 0.0005） E2：P4 ratio compared with ***： In conclusion, 1） the persistence of vascularization in the remaining follicle wall may contribute to the formation of RF after follicle aspiration,

关键词： Doppler Ovary Ovum pick-up Steroidogenesis Vascularization

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Female competition for availability of males in insects:the Nezara viridula(Linnaeus,1758)model

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Insect Science 2020年第4期27卷 801-814页

作者： Andrej Cokl Alenka Zunic Kosi Raul Alberto Laumann Meta Virant-Doberlet Department of Organisms and Ecosystems Research National Institute of BiologyLjubljanaSI-1000Slovenia Semiochemicals Laboratory Embrapa Genetic Resources and BiotechnologyBrasiliaDF 71070Brazil

Multimodal communication in solitary stinkbugs enables them to meet,mate and *** plant-dwelling species exchange information during the calling phase of mating behavior using substrate-borne vibratory signals.A female-biased gender ratio induces rivalry and competition for a sexual *** competition for males,first described among Heteroptera in three stinkbug species,revealed species specific differences and opened the question of plasticity in individually emitted temporal and frequency signal characteristics during calling and rival *** address this question and gain an insight into the mechanisms underlying stinkbug female rivalry,we compared the characteristics of alternated signals in the southern green stinkbug Nezara viridula(Linnaeus,1758)(Hemiptera:Pentatomidae).Compared to male rivalry,female rivalry is more complex,lasts longer and runs through successive phases by a combination of different song *** male pheromone triggers alternation between females,producing song pulses that occasionally overlap each *** female initiates the rivalry by changing individual pulses into pulse trains of three different *** competing female alternates with pulses of changed temporal characteristics at lower levels of rivalry and by varying the frequency characteristics of pulse trains at higher *** female rivalry,the male either stops responding or occasionally emits calling and courtship signals in response to the female that has produced signals of steady temporal *** rivalry shows complex and species specific patterns of information exchange at different levels with a broad-range variation of temporal and frequency characteristics of,until now,unidentified vibratory emissions.

关键词： biotremology female social conflict Nezara viridula rivalry signal discrimination

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Arrested development? Investigating the role of bamboo in Araucaria Forest succession in Southern Brazil

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Journal of Plant Ecology 2019年第6期12卷 1034-1046页

作者： Betina Kellermann AndréEduardo Biscaia Lacerda embrapa Forestry Brazilian Agriculture Research CorporationEstrada da Ribeirakm 111Caixa Postal 319Colombo 83411-000PRBrazil

Aims Assessing the role of a dominant native bamboo species on tree species diversity and structure in the medium *** Over a 7-year period,we studied the natural regeneration of two dominant forest types in Southern Brazil(Araucaria Forest or AF;Bamboo Forest or BF)after a bamboo(Merostachys skvortzovii Send.)die-off between 2004 and *** study was carried out in the embrapa Research Station in Cacador,Santa Catarina State,*** Findings The die-off provided ideal conditions for the establishment of several species and it kickstarted forest succession dynamics,which in turn affected regeneration *** species richness was relatively stable with a transitory increase between 2007 and 2014 in both AF and ***,species richness rose in BF because of a relative increase in abundance of some species(especially late and secondary species)while a plunge in some pioneer species drove an increase in ***,we found that BF has a lower diversity of recruits and that density declined over time,while AF is more diverse,with a more stable *** BF,the bamboo die-off created optimal conditions for initial regeneration development(mainly fast-growing pioneer trees),which quickly transited to higher size ***,after this initial stage of pioneer recruitment,the number of recruits dropped followed by a virtual absence of growth regardless of the species group as a result of a quick bamboo *** bamboo recreated a dense understory it reduced species diversity to original levels,suggesting a self-maintaining cycle that halts forest *** the other hand,the bamboo die-off had little impact on AF where a slow recruitment process typical of old-growth forests was *** results indicate that the die-off event had a temporary effect on species diversity *** to forests where bamboos are dominant in a similar process described in other southern South American *** the first study to obser

关键词： dominant species Merostachys skvortzovii Send. forest succession biodiversity forest regeneration

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Winter Oilseed Crops after Soybeans as Tools for Weed Management in Brazilian Savannah Cropping Systems

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American Journal of Plant Sciences 2014年第15期5卷 2277-2288页

作者： Germani Concenco Cesar Jose da Silva Michely Tomazi Rodolpho Freire Marques Sabrina Alves dos Santos Maxwell Eliezer dos Santos Alves Waggner Gomes Palharini Air Lisboa Froes Denise Nascimento Fabris AgroEnergy Embrapa Western Agriculture Dourados Brazil Climate Change Embrapa Western Agriculture Dourados Brazil embrapa Western Agriculture Dourados Brazil Federal University of Dourados Dourados Brazil Weed Science Embrapa Western Agriculture Dourados Brazil

We aimed with this study to evaluate the potential of oilseed crops planted following soybean, in terms of their ability to inhibit the occurrence of weed species under Brazilian Savannah cropping systems. The long-term experiment was installed in 2010 at Dourados, MS, Brazil, and in completely randomized blocks design with five replications with 12 × 24 m plot size. For three consecutive years (2010/11, 2011/12 and 2012/13), soybeans were planted in all the area by October/November being harvested in February/March, when previously marked plots were planted in April with: (1) radish (Raphanus sativus);(2) rapeseed (Brassica napus);(3) crambe (Crambe abyssinica);(4) winter fallow-no plantation after soybeans. In all years the same crop was repeated at the same plots, with no crop rotation. Phytosociological characterization of weed species was carried out in winter (after oilseeds harvest), pre-planting and post-emergence of soybean for the three years. Relative abundance, frequency and dominance, as well as the importance value for each species, was obtained. Areas were also intra-characterized by the coefficients of Simpson, Shannon-Weiner and Shannon-Weiner’s Evenness Proportion, and areas were compared for species dissimilarity with Jaccard’s presence-only coefficient, by multivariate cluster analysis. Oilseed crops definitely contribute for sustainable weed management as a cultural tool. The most important oilseed crop weeds in the Savannah-like region of Brazil were Amaranthus hybridus, Richardia brasiliensis, Lepidium virginicum, Leonotis nepetifolia and Hybanthus parviflorus. After three years of repetitive crop succession, some weeds were selected, and rotation in Winter is advised at least every two or three years.

关键词： Phytosociology Diversity Similarity Sustainability

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Availability of Information about Sustainable Bioenergy Technologies:The Agro-Energy Tree of Knowledge

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Journal of Sustainable Bioenergy Systems 2013年第4期3卷 260-264页

作者： Jose Gilberto Jardine Esdras Sundfeld Frederico Ozanan Machado Duraes embrapa Informatica Agropecuaria Computational BiologyCampinasBrasil embrapa Agroenergia BrasiliaBrasil

In addition to the efforts undertaken by research institutions to generate new knowledge and technologies, it is also necessary to promote the results of this research. Specifically, there is a need for an information system that aggregates, organizes and systematizes information about agro-energy technology and makes it available on the Internet. Despite the abundance of information circulating on the internet in Brazil, a specific method for sharing valid scientific and technological information of practical interest, such as technical guidance and recommendations for processing various materials and production technologies for various forms of agro-energy, has not yet been established. This article presents the Agro-energy Tree of Knowledge, a tool developed by embrapa to enable web access to comprehensive information about bioenergy production systems applied in different regions and conditions, in addition to texts, publications, statistical data about production and economic markets and information links related to agro-energy.

关键词： Clean Energy Ethanol Biodiesel Renewable Energy

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Performance of tetraploid alfalfa genotypes as exposed to aluminum toxicity

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Agricultural Sciences 2012年第2期3卷 230-240页

作者： Leonidas PPassos Maurício Marini Kopp Francisco J.Silva Lédo embrapa Dairy Cattle Juiz de ForaBrazil embrapa Southern Animal Husbandry BagéBrazil

A study was carried out to evaluate the development of 12 tetraploid alfalfa cultivars exposed to Al toxicity in nutrient solution. Newly germinated seedlings of cultivars Alfa 200, Alto, Araucana, Costera, Crioula, Esmeralda, Falcon, F-708, Rio, Romagnola, Valley Plus, and Victoria, were exposed to either 0, 4, 8 or 12 mg·L-1 Al3+. Plants were analyzed regarding root length (RL) and dry matter (RDM), aerial part length (APL), and dry matter (APDM), hypocotyl length (HypL) and dry matter (HypDM), epicotyl length (EpiL) and dry matter (EpiDM), and petiole length (PetL), and dry matter (PetDM). Results indicated that, although all genotypes exhibited detectable sensitivity to such a stress, cvs. Crioula, Victoria and Alpha-200 were tolerant to 4 mg·L-1 Al3+ toxicity. It was also concluded that Al3+ levels up to the 4 mg·L-1 will be effective for screening tetraploid alfalfa genotypes regarding this type of stress, when evaluations are made in nutrient solution. Finally, RL is the most suitable variable for conducting such evaluations, but all variables related to dry matter in the aerial part are also recommended.

关键词： Alfalfa Aluminum Toxicity Genotypes Nutrient Solution Selection

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Cover Crops as Affecting Soil Chemical and Physical Properties and Development of Upland Rice and Soybean Cultivated in Rotation

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Rice science 2018年第6期25卷 340-349页

作者： Adriano Stephan NASCENTE Luis Fernando STONE embrapa Arroz e Feij(CNPAF) Rodovia GO-462km 12 Zona RuralCP.17975375-000Santo Antoio de GoiasGOBrasil

Cover crops can provide changes in soil chemical and physical properties, which could allow a sustainable development of soybean and upland rice rotation in Brazilian Cerrado. The objective of this study was to determine the effects of cover crops(cultivated in the offseason) in the soybean-upland rice rotation(cultivated in the summer season) on the soil chemical and physical properties, yield components and grain yield of the cash crops. The experimental design was a randomized block design in factorial scheme 4 × 2 with six replications. Treatments were composed by four cover crops: fallow, millet(Pennisetum glaucum) + Crotalaria ochroleuca, millet + pigeon pea(Cajanus cajans), and millet + pigeon pea + Urochola ruziziensis in the offseason with one or two cycles of cover crops, with rice(Oryza sativa)or soybean(Glycine max) in the summer season. Cover crops alone provided no changes in soil chemical properties. However, the rotation cover crops/cash crops/cover crops/cash crops reduced p H, Al and H + Al and increased Ca, Mg, K and Fe contents in the soil. The cover crops millet + pigeon pea and millet + pigeon pea + U. ruziziensis improved soil physical properties in relation to fallow,especially in the 0–0.10 m soil layer. In spite of the improvement of the soil physical properties after two years of rotation with cover crops and cash crops, the soil physical quality was still below the recommended level, showing values of macroporosity, S index and soil aeration capacity lower than 0.10 m3/m3, 0.035 and 0.34, respectively. Upland rice production was higher under mixtures of cover crops than under fallow, mainly because of soil physical changes done by these mixtures of cover *** grain yield was similar under all cover crops tested, but was higher after the rotation cover crops/upland rice/cover crops than after only one cycle of cover crops.

关键词： crop rotation no-tillage system sustainable agriculture tropical agriculture rice soybean

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Agrobacterium tumefaciens-mediated transformation of Eucalyptus urophylla clone BRS07-01

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Journal of Forestry Research 2020年第2期31卷 507-519页

作者： Gisela Manuela de Franca Bettencourt Carlos Ricardo Soccol Thais Salete Giovanella Luziane Franciscon Daiane Rigoni Kestring Isabel Rodrigues Gerhardt Juliana Degenhardt-Goldbach Department of Bioprocess Engineering and Biotechnology Federal University of ParanaAvenida Cel.Francisco Heraclito dos Santos210CuritibaParanaBrazil Department of Agronomy Federal University of ParanaRua dos Funcionarios1540CuritibaParanaBrazil embrapa Forestry Estrada da RibeiraKm 111ColomboParanaBrazil embrapa Agricultural Informatics Av.Andre Tosello209CampinasSao PauloBrazil

Genetic transformation is becoming routine for engineering specific traits in important clones of recalcitrant species such as Eucalyptus;however,the efficiency is still low for most species,so many researchers still use seeds instead of clones as initial *** work aimed to develop a genetic transformation protocol,based on a highly efficient in vitro organogenesis protocol,for an Eucalyptus urophylla clone selected in our breeding *** growth regulators were evaluated for indirect organogenesis and *** a two-step protocol,the combination of callus induction media supplemented with 0.5 μM thidiazuron+0.5 μM naphthaleneacetic acid(NAA)and shoot induction media supplemented with 5.0 μM benzylaminopurine+1.0 lM NAA allowed up to 85.6%shoot formation with more shoots per explants when compared with other *** plants expressing the uidA gene were obtained using Agrobacterium tumefaciens and selected for kanamycin resistance.A RAPD analysis was used to check for somaclonal *** tests using 11 RAPD primers,we did not observe somaclonal variation in the in vitro stages evaluated.

关键词： Eucalyptus Genetic transformation In vitro regeneration Plant growth regulators Somaclonal variation

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Microbial Attributes of Infested Soil Suppressive to Bacterial Wilt by Bokashi Amendments

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Agricultural Sciences 2015年第10期6卷 1239-1247页

作者： Mariana R.Fontenelle Carlos A.Lopes Carlos E.P.Lima Daiane C.Soares Luciana R.B.Silva Daniel B.Zandonadi Ronessa B.Souza Antonio W.Moita embrapa Hortalicas/CNPH BrasiliaBrazil

Bacterial wilt, caused by Ralstonia solanacearum, is a major tomato disease in tropical and sub-tropical regions. It is difficult to be managed, since no single measure confers significant contribution for disease control. Among the cultural practices available for disease management, bokashi provides nutrients to the plants, increasing the microbial biomass, improving the quality of the soil and, in some cases, protecting plants against diseases. In this work, we evaluated the effect of three different bokashis (embrapa—BE;poultry—BP and cattle—BC) in two soils artificially and naturally infested with R. solanacearum, on the suppression of bacterial wilt in tomato. Disease control is discussed upon measurements on the contents of microbial biomass carbon (MBC), on total organic carbon (TOC), on basal respiration (BR), on metabolic coefficient (qCO2) and on microbial coefficient (qMIC). The experiment was implemented in greenhouse, with completely randomized design and factorial arrangement of treatments 2 × 3 (two soils × three bokashis). Disease suppression, assessed through wilt incidence 20 and 30 days after transplanting, was better observed in the naturally infested soil, where BP and BE were more efficient in controling the disease. TOC contents were higher in the artificially infested soil compared to that naturally infested, whereas the qMIC presented higher value for the naturally infested soil, which had greater contribution of MBC. Higher rates of BR and qCO2 were observed for the naturally infested soil with BC, probably indicating high plant stress caused by the disease in this treatment. Moreover, a high and positive correlation coefficient was found between the variables qCO2 and the number of infected plants at 30 days after transplanting. In the artificially infested soil, a negative correlation was found between the number of infected plants at 20 days after transplanting and TOC.

关键词： Basal Respiration Disease Control Microbial Biomass Ralstonia solanacearum Solanum lycopersicum

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Evaluation of Milk Compositional Quality and Mammary Gland Health of Dairy Herds in the Southwestern Brazilian Amazon

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Open Journal of Veterinary Medicine 2016年第9期6卷 139-148页

作者： Luciana G. Brito José R. Vieira Júnior Fábio da S. Barbieri Rodrigo B. Rocha Marivaldo R. Figueiró Websten C. da Silva Gilvânia L. O. Carvalho José de Arimatéia Silva Guilherme N. Souza embrapa RondÔ nia Porto Velho Brazil embrapa Eastern Amazon Belém Brazil embrapa Dairy Cattle Juiz de Fora Brazil Emater RondÔ nia Porto Velho Brazil

Samples of raw milk from bulk cooling tanks were collected in five municipalities of the Southwestern Brazilian Amazon to establish the prevalence of Staphylococcus aueus and Streptococcus agalactiae, as well as to evaluate the milk composition and its correlation with the bulk tank somatic cell count (BTSCC). A total of 250 samples were collected to investigate the causal agents of bovine mastitis in whole milk, from 50 bulk milk tanks in each municipality. Under laboratory conditions, the samples were diluted to 1/10 and 1/100, and samples of 0.1 ml from each dilution were plated in triplicate on selective media for Staphylococcus aureus and Streptococcus agalactiae. To evaluate the correlation between the major milk components (fat, protein and lactose) and the BTSCC, samples were collected for 18 months from 73 dairy herds. The presence of the above-mentioned contagious mastitis pathogens was detected in 97.2% (243/250) of refrigerated raw milk samples evaluated. Analysis of the major milk components and BTSCC demonstrated that during the study period, fat compo-nent showed the largest variance, followed by protein and lactose, which also showed significant variances.

关键词： Bulk Tank Somatic Cell Count Udder Health Milk Quality Amazon Region

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