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排序方式: 共有294条查询结果,搜索用时 15 毫秒
81.
Pimentel Dde S Ramos CA Ramos RA de Araújo FR Borba ML Faustino MA Alves LC 《Veterinary parasitology》2012,185(2-4):286-289
This paper describes an outbreak of Trypanosoma vivax for the first time in the state of Pernambuco, Brazil, affecting dairy cattle in the municipality of Itambé in the northern coastal zone of the state. Clinical signs compatible with infection by blood protozoa and epidemic miscarriages were observed. The diagnosis of T. vivax was confirmed through biometric microscopy and molecular analysis with PCR and DNA sequencing. The T. vivax isolate detected in the present study proved to be genetically very close to other Brazilian isolates of the protozoan despite being geographically distant. 相似文献
82.
Bernardo Nascimento ANTUNES Diego DA COSTA Michelli Westphal DE ATAIDE Allana Valau MOREIRA Luis Fernando PEDROTTI Francisco Schulz JÚNIOR Cassiano Schmitz NHOATO Renan Alves STADLER Marco Augusto Machado SILVA Maurício Veloso BRUN 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2020,82(12):1802
The purpose of this study was to assess the unilateral prefemoral coelioscopic-assisted approach for ovariosalpingectomy in a d`Orbigny slider (Trachemys dorbigni) using a digital otoscope. Twenty healthy turtles were randomly assigned to one of two groups, for right (GR; n=10) or left (GL; n=10) prefemoral access, for coelioscopic-assisted ovariosalpingectomy. Anesthesia and surgery times, body weight, and ovary/oviduct weight data were recorded. Anesthesia and surgery times did not differ significantly between the groups. Wound closure was the most time-consuming surgical step. Ovary and body weights significantly affected the exposure time of the ipsilateral and contralateral ovaries, respectively. Two intraoperative complications were reported. All the animals recovered uneventfully. The digital otoscope can be safely and effectively used for coelioscopic-assisted single-access, unilateral prefemoral ovariosalpingectomy in d`Orbigny slider. 相似文献
83.
Addition of Seminal Plasma to Post‐thawing Equine Semen: What is the Effect on Sperm Cell Viability?
de Andrade AF Zaffalon FG Celeghini EC Nascimento J Tarragó OF Martins SM Alonso MA Arruda RP 《Reproduction in domestic animals》2011,46(4):682-686
Effect of seminal plasma addition after thawing on viability or cryocapacitation is not definitively established. This experiment was performed to verify the effect of adding seminal plasma, autologous or homologous (from an animal with good semen freezability). Five ejaculates from each of four stallions with proven fertility were collected and cryopreserved. The semen was subsequently thawed and divided into the following three treatment groups: no seminal plasma addition after semen thawing (NOSP); the addition of homologous seminal plasma after semen thawing (HSP) and the addition of autologous seminal plasma after semen thawing (ASP). The addition of 20% of seminal plasma led to an increase in the cell population that simultaneously show plasma and acrosomal membrane integrity (p < 0.05). The addition of seminal plasma did not alter the total motility, the amount of cells with mitochondrial membrane potential or the sperm velocities (average path velocity, straight-line velocity and curvilinear velocity). However, the beat/cross-frequency, straightness and linearity were reduced in ASP and HSP groups (p < 0.05). Unexpectedly, the addition of homologous seminal plasma reduced the proportion of cells with progressive motility (p < 0.05) and the addition of autologous seminal plasma reduced the amplitude of the lateral head displacement (p < 0.05). Based on the increase in the cell populations that had the plasma and acrosomal membrane integrity simultaneously identified in this study, we proposed that the addition of seminal plasma (autologous or homologous) into post-thawed semen before insemination could increase semen fertility. 相似文献
84.
Eliane Gasparino Débora Marques Voltolini Ana Paula Del Vesco Simone Eliza Facioni Guimarães Carlos Souza do Nascimento Adhemar Rodrigues de Oliveira Neto 《Livestock Science》2013,157(1):339-344
In this study, we analyzed insulin-like growth factor I (IGF-I), growth hormone receptor (GHR) and uncoupling protein (UCP) mRNA expression in the muscle and liver of high- (0.23 g/g) and low- (0.17 g/g) feed-efficiency (FE) Japanese quail at three different air temperatures: comfortable (25 °C), heat stress (38 °C) for 12 h or cold stress (10 °C) for 12 h. Total RNA was extracted from the liver and breast muscle of each quail, and cDNA was amplified using specific primers for the target genes. Expression was analyzed using quantitative real-time PCR (qRT-PCR). IGF-I mRNA expression was higher in the livers of high-FE quail than in the livers of low-FE quail under both heat and cold stress conditions. High-FE birds also showed higher GHR mRNA expression independent of temperature. UCP mRNA expression in the liver was lower in high-FE birds and higher under heat stress compared with the other conditions. IGF-I mRNA expression was higher in the muscle of high-FE quail under the three conditions tested, and UCP mRNA expression was higher under cold stress. Our results suggest that air temperature affects the expression of genes related to growth and mitochondrial energy production, and quail with different feed efficiencies respond differently to environmental stimuli. 相似文献
85.
Fujiwara RT Vale AM França da Silva JC da Costa RT Quetz Jda S Martins Filho OA Reis AB Corrêa Oliveira R Machado-Coelho GL Bueno LL Bethony JM Frank G Nascimento E Genaro O Mayrink W Reed S Campos-Neto A 《Veterinary research》2005,36(5-6):827-838
Control of canine visceral leishmaniasis (VL) remains a difficult and serious problem mostly because there is no reliable and effective vaccine available to prevent this disease. A mixture of three recombinant leishmanial antigens (TSA, LeIF and LmSTI1) encoded by three genes highly conserved in the Leishmania genus have been shown to induce excellent protection against infection in both murine and simian models of cutaneous leishmaniasis. A human clinical trial with these antigens is currently underway. Because of the high degree of conservation, these antigens might be useful vaccine candidates for VL as well. In the present study, using the dog model of the visceral disease, we evaluated the immunogenicity of these three antigens formulated with two different adjuvants, MPL-SE and AdjuPrime. The results were compared with a whole parasite vaccine formulated with BCG as the adjuvant. In order to investigate if sensitization with the recombinant antigens would result in recognition of the corresponding native parasite antigens upon infection, the animals were exposed for four weeks after the termination of the immunization protocol with the recombinant antigens to a low number of L. chagasi promastigotes, an etiological agent of VL. Immune response was evaluated by quantitative ELISA in the animal sera before and after exposure to the viable parasites. Both antigen specific IgG1 and IgG2 antibody levels were measured. Immunization of dogs with the recombinant antigens formulated in either MPL-SE or AdjuPrime resulted in high antibody levels particularly to LmSTI1. In addition, this immunization although to low levels, resulted in the development of antibody response to the whole parasite lysate. Importantly, experimental exposure with low numbers of culture forms of L. chagasi promastigotes caused a clear boost in the immune response to both the recombinant antigens and the corresponding native molecules. The boost response was predominantly of the IgG2 isotype in animals primed with the recombinant antigens plus MPL-SE. In contrast, animals primed with the recombinant antigens formulated in AdjuPrime as well as animals vaccinated with crude antigen preparation responded with mixed IgG1/IgG2 isotypes. These results point to the possible use of this antigen cocktail formulated with the adjuvant MPL-SE in efficacy field trials against canine VL. 相似文献
86.
87.
J. Nascimento DVM MS C.F. Raphael DVM MS A.F.C. Andrade DVM M.A. Alonso DVM MS E.C.C. Celeghini DVM MS PhD R.P. Arruda DVM MS PhD 《Journal of Equine Veterinary Science》2008,28(6):351-358
The advantages of using cryopreserved semen in equine reproduction are well known. During cryopreservation, spermatozoa undergo many changes that lead to a decrease in fertility. There is no agreement on the ideal sperm dose and concentration to maximize fertility rates. Thus, the objectives of this experiment were to evaluate sperm motion by computer-assisted analysis (CASA), sperm membrane integrity and function with fluorescence probes of cryopreserved sperm at three concentrations: 100 (C100), 200 (C200) and 400 × 106 sperm/mL (C400), and two straw volumes (0.50 and 0.25 mL). There was no interaction between sperm concentration and storage volume (P > .05). Sperm motion characteristics were influenced by concentration (C100 > C200 > C400; P < .05). Curvilinear velocity (VCL) in 0.25-mL straws had higher average values (P < .05). Membrane integrity and function were not changed by straw volume (P > .05). However, sperm concentration changed the percentage of cells with intact plasma membrane (C100 > C200 > C400; P < .05) and the percentage of cells with high mitochondrial membrane potential (C100 = C200; P > .05 and C400 < C100 and C200; P < .05). According to this experiment, the best freezing method was that involving 100 × 106 sperm/mL, regardless of straw volume. 相似文献
88.
Santiago Mde A Ribeiro FC Mouta-Confort E Nascimento LD Schubach Ade O Madeira Mde F Bertho AL 《Veterinary parasitology》2008,154(3-4):341-346
Flow cytometry employing Leishmania (L.) chagasi (Lc) and L. (Viannia) braziliensis (Lb) antigen was used to establish the differential diagnosis between visceral (VL) and cutaneous leishmaniasis (CL) in dogs. Flow cytometry permitted the detection of Leishmania-specific immunoglobulin G in sera from 19 dogs: nine with CL and 10 with VL. A significant difference in the percentage of positive staining was observed in sera from dogs with CL between the homologous antigen (69% for Lb) and the heterologous antigen (42% for Lc). However, this difference was not significant in sera from dogs with VL (61% for Lb and 73% for Lc). No significant staining was observed in control sera (0.6% for Lb and 0.4% for Lc) consisting of samples from healthy dogs, or in the group with sporotrichosis (1.8% for Lb and 1.5% for Lc), a differential diagnosis of CL. The results suggest that flow cytometry might be useful for the differentiation between CL and VL in dogs, with practical applications in areas where the two infections overlap. 相似文献
89.
Amanda Mara Teles Leticia Prince Pereira Pontes Sulayne Janayna Araújo Guimares Ana Luiza Butarelli Gabriel Xavier Silva Flavia Raquel Fernandes do Nascimento Geusa Felipa de Barros Bezerra Carla Junqueira Moragas-Tellis Rui Miguel Gil da Costa Marcos Antonio Custdio Neto da Silva Fernando Almeida-Souza Ktia da Silva Calabrese Ana Paula Silva Azevedo-Santos Maria do Desterro Soares Brando Nascimento 《Marine drugs》2020,18(11)
Background: This study addresses the antitumoral properties of Penicillium purpurogenum isolated from a polluted lagoon in Northeastern Brazil. Methods: Ethyl Acetate Extracellular Extract (EAE) was used. The metabolites were studied using direct infusion mass spectrometry. The solid Ehrlich tumor model was used for antitumor activity. Female Swiss mice were divided into groups (n = 10/group) as follows: The negative control (CTL−), treated with a phosphate buffered solution; the positive control (CTL+), treated with cyclophosphamide (25 mg/kg); extract treatments at doses of 4, 20, and 100 mg/kg; animals without tumors or treatments (Sham); and animals without tumors treated with an intermediate dose (EAE20). All treatments were performed intraperitoneally, daily, for 15 days. Subsequently, the animals were euthanized, and the tumor, lymphoid organs, and serum were used for immunological, histological, and biochemical parameter evaluations. Results: The extract was rich in meroterpenoids. All doses significantly reduced tumor size, and the 20 and 100 mg/kg doses reduced tumor-associated inflammation and tumor necrosis. The extract also reduced the cellular infiltration of lymphoid organs and circulating TNF-α levels. The extract did not induce weight loss or renal and hepatic toxic changes. Conclusions: These results indicate that P. purpurogenum exhibits immunomodulatory and antitumor properties in vivo. Thus, fungal fermentation is a valid biotechnological approach to the production of antitumor agents. 相似文献
90.
Hellen Buzollo Lidiane Cristina Gonalves de Sandre Ligia Maria Neira Thiago Matias Torres do Nascimento Rosngela Kiyoko Jomori Dalton Jos Carneiro 《Aquaculture Nutrition》2019,25(3):669-679
Several investigations have been carried out to improve the productivity of tambaqui, an economically important fish species in Brazil and other Latin American countries. This study determined the digestible protein (DP) requirements in juvenile tambaqui by assessing their productive performance and nutritional efficiency. It also evaluated the effects of different dietary DP levels on the morphology and cellularity of skeletal fast muscle fibres. The 1750 tambaqui tested (6.53 ± 0.43 g body weight, 7.58 ± 0.18 cm length) were randomly distributed into 35 tanks. Fish were fed one of the seven isocaloric diets, which contained 140, 170, 200, 230, 260, 290 or 320 g/kg DP. The DP requirement, calculated by segmented (broken line) regression of weight gain data, was 290 g/kg. An increase in diet DP to 290 g/kg significantly improved final weight, weight gain, feed intake, specific growth rate and crude protein gain, and changed fibre diameter in deep muscle. Muscle fibres were randomly distributed into a mosaic pattern, characterized by fibres with different diameters. Treatments with 290 and 320 g/kg DP increased the frequency of large‐diameter fibres (>50 µm), indicating hypertrophic growth of skeletal muscle during the juvenile phase, which occurred in conjunction with hyperplasia. 相似文献