Genotyping of Streptococcus dysgalactiae strains isolated from Nile tilapia,Oreochromis niloticus (L.)     

F A A Costa  C A G Leal  R C Leite  H C P Figueiredo 《Journal of fish diseases》2014,37(5):463-469

Streptococcus dysgalactiae is an emerging fish pathogen that is responsible for outbreaks of disease on fish farms around the world. Recently, this bacterium was associated with an outbreak at a Nile tilapia, Oreochromis niloticus (L.), farm in Brazil. The aim of this study was to evaluate the genetic diversity, best genotyping method and aspects of molecular epidemiology of S. dysgalactiae infections in Nile tilapia farms in Brazil. Twenty‐one isolates from four farms located in different Brazilian states were characterized genetically using pulsed‐field gel electrophoresis (PFGE), ERIC‐PCR, REP‐PCR and sodA gene sequencing. The discriminatory power of the different typing methods was compared using Simpson's index of diversity. Identical sodA gene sequences were obtained from all isolates, and ERIC‐PCR and REP‐PCR were unable to discriminate among the isolates. PFGE typing detected three different genetic patterns between the 21 strains evaluated; thus, it was the best genotyping method for use with this pathogen. The strains from Ceará State were genetically divergent from those from Alagoas State. The S. dysgalactiae isolates analysed in this study constituted a genetically diverse population with a clear association between geographical origin and genotype.  相似文献   

Carrier state induced by oxytetracycline therapy against streptococcosis in Nile tilapia,Oreochromis niloticus (L.)     

F C Faria  C A G Leal  G A Carvalho‐Castro  R C Leite  H C P Figueiredo 《Journal of fish diseases》2014,37(9):853-857

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Cytogenetics Analysis and Testis Morphology of Aquatic Species of the Families Belostomatidae,Gelastocoridae, Gerridae,Notonectidae, and Veliidae (Heteroptera)     

Luis Lenin Vicente Pereira  Kaio Cesar Chaboli Alevi  Márcia Maria Urbanin Castanhole  Felipe Ferraz Figueiredo Moreira  Julianna Freires Barbosa  Mary Massumi Itoyama 《Journal of insect science (Online)》2015,15(1)

The Heteroptera have holocentric chromosomes with kinetic activity restricted to the end of chromosomes. The first meiotic division is reductional for the autosomes and equational for the sexual. Only a few species of this suborder have been analyzed. In this study, we observed the morphologies of the testes of the Heteroptera species Belostoma anurum (Herrich-Schäffer, 1948), Belostoma micantulum (Stal, 1858), Gelastocoris angulatus (Melin, 1929), Gelastocoris flavus flavus (Guérin-Méneville, 1844), Rheumatobates crassifemur crassifemur (Esaki, 1926), Buenoa amnigenus (White, 1879), Buenoa unguis (Truxal, 1953), Martarega brasiliensis (Truxal, 1949), Martarega membranácea (White, 1879), Martarega uruguayensis (Berg, 1883), Rhagovelia tenuipes (Champion, 1898) and Rhagovelia zela (Drake, 1959). We found that the testes of these species can be round, round/spiral, or elongated/spiral. The size of the prophase I cells was found to vary, with the smallest ones being detected in B. micantulum and Rha. zela, the largest in G. f. flavus, and ones of intermediate size in R. c. crassifemur and M. brasiliensis. With respect to the chromosome complement, we verified the presence of 2n = 16 (14A+XY, B. micantulum and G. angulatus), 21 (20A+X0, R. c. crassifemur), 23 (22A+X0, Rha. zela and Rha. tenuipes), 25 (24A+X0, Bu. amnigenus and Bu. unguis; 22A+2m+X0, M. membranacea), 27 (24A+2m+X0, M. brasiliensis and M. uruguayensis), 29 (26A+X₁X₂Y, B. anurum), and 35 (30A+X₁X₂X₃X₄Y, G. f. flavus). We found that the features of spermatogenesis in these species are similar to those of other previously described Heteroptera species, differing only in testicular morphology, chromosome number, and sex chromosome system.  相似文献   

First clues on a jasmonic acid role in grapevine resistance against the biotrophic fungus Plasmopara viticola     

Figueiredo  A.  Monteiro  F.  Sebastiana  M. 《European journal of plant pathology / European Foundation for Plant Pathology》2015,142(3):645-652

European Journal of Plant Pathology - Plants are sessile organisms being constantly under a wide array of environmental pressures. Their resistance against biotic stress is regulated by...  相似文献   

Direct seeding of Oreomunnea mexicana,a threatened tree species from Southeastern Mexico     

Edel Joshua Atondo-Bueno  Fabiola López-Barrera  Martha Bonilla-Moheno  Guadalupe Williams-Linera  Neptalí Ramírez-Marcial 《New Forests》2016,47(6):845-860

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Expression levels of mRNA-encoding PDGF receptors in goat ovaries and the influence of PDGF on the in vitro development of caprine pre-antral follicles     

Brito IR  Lima IM  Saraiva MV  Silva CM  Magalhães-Padilha DM  Araújo VR  Barreto Luz V  Barbalho Silva AW  Campello CC  Silva JR  Figueiredo JR 《Reproduction in domestic animals》2012,47(5):695-703

The aims of this study were to investigate the expression levels of mRNA for platelet-derived growth factor (PDGF) receptors (PDGFR-α and -β) in caprine follicles at different developmental stages and to evaluate the influence of PDGF on the in vitro development of pre-antral follicles. For this, goat primordial, primary and secondary follicles, as well as small (1-3 mm) and large (3-6 mm) antral follicles, were obtained, and PDGFR-α and -β mRNA levels were quantified by real-time PCR. Furthermore, pre-antral follicles (≥ 200 μm) were isolated from goat ovaries and cultured for 18 days in α- minimum essential medium supplemented with PDGF at 50 or 100 ng/ml, containing or not FSH. Real-time PCR showed highest PDGFR-α mRNA levels in secondary follicles, while PDGFR-β mRNA levels were highest in primary follicles onwards. Both receptors showed higher mRNA levels in granulosa/theca cells from small and large antral follicles than in their corresponding cumulus-oocyte complexes. In culture, the percentage of antrum formation was significantly higher in 100 ng/ml PDGF compared with the same PDGF concentration associated with FSH. After 18 days, PDGF in both concentrations associated with FSH promoted follicular growth significantly higher than the control. Moreover, the addition of FSH to 50 ng/ml PDGF positively influenced the follicular growth when compared with the same PDGF concentration in the absence of FSH. In conclusion, PDGF is important for early goat folliculogenesis, because the presence of PDGFR-α and -β mRNA was detected in all follicular categories, and PDGF associated with FSH stimulated the growth of goat pre-antral follicles isolated and cultured in vitro.  相似文献   

Uterine hemodynamic evaluation of the beginning of diestrous in mares     

Fernanda Saules Ignácio  Heloísa de Siqueira Canesin  José Carlos Figueiredo Pantoja  Rafael Mide Romano  Luiz Fernando Novaes Filho  Jair Camargo Ferreira  Cezinande de Meira 《Journal of Equine Veterinary Science》2012

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Nondestructive evaluation of heat-treated Eucalyptus grandis Hill ex Maiden wood using stress wave method     

Rosilei A. Garcia  Alexandre Monteiro de Carvalho  Jo?o Vicente de Figueiredo Latorraca  Jorge Luis Monteiro de Matos  Wanessa A. Santos  Rafael Fonseca de Medeiros Silva 《Wood Science and Technology》2012,46(1-3):41-52

The objectives of this study were to evaluate the effect of heat treatment of eucalypt wood (Eucalyptus grandis Hill ex Maiden) on the dynamic modulus of elasticity by using the stress wave nondestructive method and also to determine the air-dry density variation, weight loss and equilibrium moisture content following treatment. Heat treatments were performed at four different temperatures (180, 200, 215 and 230°C) and for three different durations (15?min, 2 and 4?h). The results revealed a significant reduction in air-dry density following heat treatment independent of temperature and time. A significant weight loss was observed between and within treatments. The treatment at 230°C for 2 and 4?h produced a weight loss of 20.5 and 26.5%, respectively, which was statistically different from other treatment conditions. The dynamic modulus of elasticity decreased by about 13% in the most severe treatment (230°C for 4?h). Depending on the temperature and time, the equilibrium moisture content was significantly reduced within the range of 40–74%.  相似文献   

Combining ability among apomictic and sexual parents of Urochloa humidicola     

Ulisses Jos de Figueiredo  Sanzio Carvalho Lima Barrios  Cacilda Borges do Valle  Jos Airton Rodrigues Nunes 《Grass and Forage Science》2019,74(4):678-686

The diallel cross constitutes an informative genetic design for choosing genitors and crosses in breeding programmes since it provides estimates of general (GCA) and specific (SCA) combining abilities. Because the breeding programme for Urochloa humidicola ([Rendle] Morrone & Zuloaga; syn. Brachiaria humidicola [Rendle] Schweick) at Embrapa Beef Cattle is recent, these estimates are still unknown. Thus, the aim of this study was to obtain the estimates of GCA and SCA from the partial diallel cross design between sexual and apomictic parents. The crosses involved nine sexual and ten apomictic parents. Seventy‐one full‐sib progenies were obtained and evaluated in an incomplete block design, using all parents and the cv. BRS Tupi as a check. The agronomic and forage quality traits were evaluated using seven harvests. Statistical analysis was performed using the mixed model approach. Significant variations were associated with GCA among sexual parents for biomass yield and forage quality traits. However, this cannot be observed for apomictic parents for GCA. The SCA effect was not significant for the assessed traits. These results showed the predominance of additive effects. Sexual parents SEX3 and SEX4 presented the highest potential for contributing favourable alleles in hybrid combinations. The absence of GCA among apomictic parents and SCA suggests the need to increase genetic variability for the generation of breeding populations of U. humidicola.  相似文献   

Performance of three tropical hair sheep breeds.   总被引：1，自引：0，他引：1  

M H Rajab  T C Cartwright  P F Dahm  E A Figueiredo 《Journal of animal science》1992,70(11):3351-3359

The performance of three hair sheep breeds (Brazilian Somali, Morada Nova, and Santa Ines) was evaluated in the production environment of northeastern Brazil. Data from a total of 524 lambs sired by 21 rams and out of 190 ewes were analyzed. These data were collected from 1980 to 1983 at Sobral, Brazil from an experiment designed to compare performance of the three breeds. The traits included weights of lambs at birth, weaning, 8 mo, 10 mo, and yearling ages and ewe characters of weight at lambing (EWT), total lamb weight born (LWB), total lamb weight weaned (LWW), and prolificacy rate (PR). Differences (P < .01) among breeds were found for all characters. The Brazilian Somali, the smallest and slowest-gaining breed, was less sensitive to yearly variation than were the other breeds. The Santa Ines, the largest and fastest-gaining breed, was superior in LWB and LWW per ewe lambing. Averaged over the 4-yr period, the Morada Nova had the highest PR (1.82), and the Brazilian Somali and Santa Ines had similar PR (1.39 and 1.31, respectively). Environmental effects on PR due to yearly rainfall quantity and distribution pattern influenced lamb growth up to weaning and ewe reproduction performance. Breed x year (P < .05) interaction effects on PR were largely attributable to the Somali breed's exhibiting higher PR than the Santa Ines and Morada Nova breeds during the relatively wet years of 1981 and 1982.  相似文献