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11.
Pinto PM Chemale G de Castro LA Costa AP Kich JD Vainstein MH Zaha A Ferreira HB 《Veterinary microbiology》2007,121(1-2):83-93
Mycoplasma hyopneumoniae is an important pathogen for pigs, being the causative agent of enzootic pneumonia. Recently, the genome sequences of three strains, J, 7448 and 232 have been reported. Here, we describe the results of a proteomic analysis, based on two-dimensional gel electrophoresis of soluble protein extracts, immunoblot and mass spectrometry, which was carried out aiming the identification of gene products and antigenic proteins from the M. hyopneumoniae pathogenic strain 7448. A preliminary M. hyopneumoniae proteome map in two pH ranges (3-10 and 4-7) was produced. A total of 31 different coding DNA sequences (CDSs), including three hypothetical ones, were experimentally verified with the identification of the corresponding protein products by matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry. According to the Clusters of Orthologous Groups (COG) functional classification, the identified proteins were assigned to the groups of metabolism (13), cellular processes (5) and information and storage processing (4). Nine of the identified proteins were not classifiable by COG, including some related to cytoadherence and possibly involved in pathogenicity. Moreover, at least five highly antigenic proteins of M. hyopneumoniae were identified by immunoblots, including four novel ones (a heat shock protein 70, an elongation factor Tu, a pyruvate dehydrogenase E1-beta subunit and the P76 membrane protein). The now available proteome map is expected to serve as a reference for comparative analyses between M. hyopneumoniae pathogenic and non-pathogenic strains, and for methabolic studies based on cells cultured under modified conditions. 相似文献
12.
This study evaluated the use of an avirulent live Salmonella Choleraesuis vaccine to reduce the seroprevalence and number of Salmonella carrier pigs at slaughter. Seven batches of 500 pigs were included in each of the two study groups: the vaccinated group (VG) that was orally vaccinated and the control group (CG) that received a placebo on the first day of life. The groups were managed in a three-site system and followed up from birth to slaughter. Blood samples (n=378) were collected from each VG and CG to monitor the on-farm seroprevalence in both groups. Mesenteric lymph nodes and blood from animals (n=390) belonging to each group were collected at slaughter. At the first day of life, the seroprevalence in control batches ranged from 77.9 to 96.3 per cent, while in vaccinated batches, it ranged from 66.6 to 92.6 per cent. At weaning (21 days of age), the number of seropositives decreased in both groups (mean of 12 and 3.7 per cent for CG and VG, respectively). At slaughter, batches of VG had a significantly (P<0.0001) lower seroprevalence (46.6±5 per cent) and isolation of Salmonella from lymph nodes (33.1±5 per cent) compared with CG batches (79.7±4 per cent and 59.5±5 per cent, respectively). The results indicate that administration of a Salmonella choleraesuis-attenuated vaccine on the first day of life decreases Salmonella isolation and seroprevalence in pigs at slaughter. 相似文献
13.
C��ssia ?ngela Pedrozo M��rcio Henrique Pereira Barbosa Felipe Lopes da Silva Marcos Deon Vilela de Resende Luiz Alexandre Peternelli 《Euphytica》2011,182(3):423-430
This study was designed to estimate the repeatability coefficient of traits of the plant-cane and first rattoon in a large number of full-sib sugarcane families and to select the superior families based on their predicted genotypic values. The population used in this study consisted of 190 families, and crossing was performed at the Federal University of Alagoas, in Murici, Alagoas, Brazil, in 2007. Five experiments, each with 22 families, took place at the Centro de Pesquisa e Melhoramento da Cana-de-Açúcar (CECA), in Oratórios, Minas Gerais, while four experiments, each with 20 families, took place at the Volta Grande mill (VGM), in Conceição das Alagoas, Minas Gerais. Each experiment took the form of a randomized complete block design with six replications. The following traits were determined from the plant-cane and first rattoon: percentage of soluble solids w/w in the juice (Brix), tons of stalks per hectare (TSH) and tons of brix per hectare (TBH). Statistical analyses were performed using the mixed model methodology. Variance components were estimated by restricted maximum likelihood (REML) and the genotypic values of families were predicted by best linear unbiased prediction (BLUP). The moderately high estimates of repeatability for TSH and TBH and the high rates of coincidences of the families selected in both plant-cane and first rattoon indicate that selection of families using repeated measures across the first two harvests combined with individual clone selection at the rattoon stage may be efficient in sugarcane breeding programs, increasing the efficiency of obtaining new cultivars. 相似文献
14.
Guilherme Augusto Peres Silva Lígia Regina Lima Gouvêa Cecília Khusala Verardi Marcos Deon Vilela de Resende Erivaldo José Scaloppi Junior Paulo de Souza Gonçalves 《Euphytica》2013,189(3):343-350
Knowledge of the traits present in plant populations of a species is essential to carry out selection and breeding. The objective of the present study was to estimate the genetic parameters and correlate genetically and phenotypically the variables rubber yield, annual trunk girth increase, number of latex vessel rings and bark thickness in early measurement cycles. A total of 22 rubber tree progenies (Hevea brasiliensis) were assessed in three locations during three early measurement cycles. The bark thickness variable correlated significantly for the three increase measurements made in the locations of Jaú, Pindorama and Votuporanga. The progeny mean based joint hereditability showed mean values greater than individual plants and within progeny plants of 0.848, 0.286 and 0.242, respectively. The variables annual trunk girth increase and bark thickness are genetically correlated variables. Rubber yield is correlated genetically with bark thickness that permits simultaneous selection for the two characteristics. The early measurement cycles were efficacious for finding genetic variability among the genotypes. 相似文献
15.
Gehring R van der Merwe D Pierce AN Baynes RE Craigmill AL Riviere JE 《American journal of veterinary research》2005,66(1):108-112
OBJECTIVE: To investigate the feasibility of using multivariate cluster analysis to meta-analyze pharmacokinetic data obtained from studies of pharmacokinetics of ampicillin trihydrate in cattle and identify factors that could account for variability in pharmacokinetic parameters among studies. SAMPLE POPULATION: Data from original studies of the pharmacokinetics of ampicillin trihydrate in cattle in the database of the Food Animal Residue Avoidance Databank. PROCEDURE: Mean plasma or serum ampicillin concentration versus time data and potential factors that may have affected the pharmacokinetics of ampicillin trihydrate were obtained from each study. Noncompartmental pharmacokinetic analyses were performed, and values of pharmacokinetic parameters were clustered by use of multivariate cluster analysis. Practical importance of the clusters was evaluated by comparing the frequency of factors that may have affected the pharmacokinetics of ampicillin trihydrate among clusters. RESULTS: A single cluster with lower mean values for clearance and volume of distribution of ampicillin trihydrate administered PO, compared with other clusters, was identified. This cluster included studies that used preruminant calves in which feeding was withheld overnight and calves to which probenecid had been administered concurrently. CONCLUSIONS AND CLINICAL RELEVANCE: Meta-analysis was successful in detecting a potential subpopulation of cattle for which factors that explained differences in pharmacokinetic parameters could be identified. Accurate estimates of pharmacokinetic parameters are important for the calculation of dosages and extended withdrawal intervals after extralabel drug administration. 相似文献
16.
Jalusa Deon Kich Patrícia Schwarz Luis Eduardo Silva Arlei Coldebella Itamar Ant?nio Piffer Remídio Vizzoto Marisa Ribeiro de Itapema Cardoso 《Journal of veterinary diagnostic investigation》2007,19(5):510-517
The implementation of Salmonella control programs in the pork production chain demands rapid and cost-effective methods to assess the prevalence of infection in pig herds. The objective of the present study was to develop an in-house enzyme-linked immunosorbent assay (ELISA) based on S. Typhimurium lipopolysaccharides (LPS) to measure the prevalence of infection caused by Salmonella in swine herds. Coating antigen was produced by phenol extraction of S. Typhimurium culture. After standardization of ELISA test conditions, the assay was validated by testing serum samples on different animal categories: pigs orally inoculated with S. Typhimurium and sentinel animals in contact with them, naturally infected animals, colostrum-deprived piglets, and bacterin-immunized pigs. Seroconversion was observed in inoculated pigs (7 days postinfection [DPI]) and in the sentinels (21 DPI). Nonspecific reactions were not detected in the sera of colostrum-deprived animals. Serum samples from animals immunized with Salmonella Agona, Salmonella Derby, Salmonella Panama, and Salmonella Bredeney bacterins showed marked cross-reaction with the LPS from the serovar Typhimurium. Moreover, positive results obtained with the in-house ELISA were associated with Salmonella isolation in 75 infected pig herds. Comparisons with 2 commercial kits showed a linear correlation coefficient of 0.847 between the in-house ELISA and kit A and 0.922 with kit B but a low agreement in the qualitative results. In conclusion, the newly developed in-house ELISA based on S. Typhimurium LPS can be a useful tool to determine the intensity of Salmonella sp. infection in swine herds. 相似文献
17.
Retinoid signaling determines germ cell fate in mice 总被引：1，自引：0，他引：1
Bowles J Knight D Smith C Wilhelm D Richman J Mamiya S Yashiro K Chawengsaksophak K Wilson MJ Rossant J Hamada H Koopman P 《Science (New York, N.Y.)》2006,312(5773):596-600
Germ cells in the mouse embryo can develop as oocytes or spermatogonia, depending on molecular cues that have not been identified. We found that retinoic acid, produced by mesonephroi of both sexes, causes germ cells in the ovary to enter meiosis and initiate oogenesis. Meiosis is retarded in the fetal testis by the action of the retinoid-degrading enzyme CYP26B1, ultimately leading to spermatogenesis. In testes of Cyp26b1-knockout mouse embryos, germ cells enter meiosis precociously, as if in a normal ovary. Thus, precise regulation of retinoid levels during fetal gonad development provides the molecular control mechanism that specifies germ cell fate. 相似文献
18.
José Manoel Colombari Filho Marcos Deon Vilela de Resende Orlando Peixoto de Morais Adriano Pereira de Castro Élcio Perpétuo Guimarães José Almeida Pereira Marley Marico Utumi Flávio Breseghello 《Euphytica》2013,190(1):117-129
A durum wheat recombinant inbred line population developed from PDW 233 × Bhalegaon 4 cross was analyzed in five environments to understand the genetic network responsible for test weight (TW), thousand kernel weight (TKW), grain yield (YLD), spike length (SL), spikelets per spike (SPS), kernels per spike (KER) and kernel weight per spike (KWS). Genotype, environment and their interactions were main sources of variance for all the traits. TW and TKW were influenced by 11 main effect QTL and 6 digenic epistatic interactions detected on chromosomes 2A, 2B, 4B and 7A. Grain yield was influenced by three epistatic interactions and five main effect QTL, of which two on chromosome 2A were most consistent. A major QTL for spike length was observed on chromosome 3B. QTL for spike characters were distributed over 9 chromosomes. All the traits showed significant influence of digenic epistasis (QQ) and, to a certain extent, QTL × environment interactions (QQE). Therefore, while breeding for complex traits like kernel characters and grain yield components, these interactions should also be considered important. The consistent QTL on chromosome 2A between the marker interval Xgwm71.2–Xubc835.4 with pleiotropic effect on TW and TKW, may be utilized in early generation selection to improve TW and TKW and thereby the milling potential of the durum wheat. 相似文献
19.
Long-term selection experiments provide germplasm to study the effects of selection in a closed population. Recurrent selection
to enhance grain yield in oat has been ongoing at the University of Minnesota since 1968. The objectives of this study were:
(i) estimate the GCA and SCA effects for three agronomic traits in the seventh cycle of selection, (ii) assess the effect
of the current methods of selection on parental contribution and unselected traits, and (iii) determine the direct and indirect
responses to seven cycles of recurrent selection for grain yield. Progeny of the Cycle 6 parents and parents for Cycles 0
through 7 were grown in two separate tests. Grain yield, heading date and plant height were evaluated in each test. Grain
yield was increased by 21.7% after seven cycles of selection. Evaluation of Cycle 6 progeny showed that GCA effects were significant
for all three traits studied, and SCA effects were significant only for grain yield. Four Cycle 6 parents did not have any
progeny selected as Cycle 7 parents. Results from this study indicate that long term recurrent selection has continued to
increase grain yield. Alternative selection strategies may be necessary to maintain the genetic variability in this population,
particularly when improvement of secondary traits is required.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
20.
José Marcelo Soriano Viana Ísis Fernanda de Almeida Marcos Deon Vilela de Resende Vinícius Ribeiro Faria Fabyano Fonseca e Silva 《Euphytica》2010,174(1):31-39
Best Linear Unbiased Prediction (BLUP) has become the most widely used method for genetic assessment of animal and perennial species, and it is potentially relevant for annual crops. The objective of this study was to assess this method for selection within non-inbred families in recurrent breeding programs. The ‘animal model’ was fitted. The data were expansion volume (EV) and grain yield of plants in recombination plots of two to three selection cycles in the popcorn population Viçosa, with half- and full-sib progenies. The ASReml program was used to perform the analyses. For both EV and yield the breeding values predicted from the additive and additive-dominant models were highly correlated. Multi-generation BLUP was, in general, more accurate than single-generation analysis. These two methods resulted in highly correlated predicted breeding values. The dominance genetic values predicted from the single- and multi-generation analysis were also highly correlated. The pedigree information reduced the percentage of coincidences among the selected individuals relative to phenotypic selection mainly in the population structured in half-sib families. Based on breeding values predicted by BLUP analysis, the most efficient selection procedure was mass selection. 相似文献