Virulence factors of avian pathogenic Escherichia coli isolated from broilers from the south of Brazil     

da Rocha AC  da Silva AB  de Brito AB  Moraes HL  Pontes AP  Cé MC  do Nascimento VP  Salle CT 《Avian diseases》2002,46(3):749-753

Sixty-three Escherichia coli strains isolated from broilers with respiratory problems were examined for virulence factors, hemolysin synthesis ability, motility, hemagglutination capacity, operon pap presence, colicin production, and serum resistance. The capacity to hemagglutinate guinea pig erythrocytes was found in 53 (84.1%) of the samples, but only 30 (47.6%) agglutinated chicken erythrocytes. D-mannose-sensitive hemagglutination against guinea pig erythrocytes was found in 19 (30.2%) samples and against chicken erythrocytes, in 15 (23.8%) samples, whereas the D-mannose-resistant hemagglutination with guinea pig erythrocytes was found in 34 (54%) samples, and 13 of these (20.6%) showed this characteristic against chicken erythrocytes. Operon pap, P fimbria codifier, was detected in 26 samples in a total of 34 D-mannose-resistant samples. Colicin production was observed in 55 (87.3%) of the strains, and 41.8% presented V colicin production. Of the samples analyzed, 56 (88.9%) presented serum resistance, six (9.5%) were intermediate, and only one (1.6%) was sensitive to the action of the complement. The diversity of virulence profiles detected in the samples in this study explains in part the multifactorial characteristics of avian colibacillosis.  相似文献   

A rapid and simple method for the separation of pure lymphocytes from horse blood     

Zizzadoro C  Belloli C  Badino P  Ormas P 《Veterinary immunology and immunopathology》2002,89(1-2):99-104

A method for the separation of pure and viable lymphocytes and granulocytes from the same blood sample in horses was reported. By centrifuging equine heparinized blood at 100 xg for 10 min at room temperature (r.t.), the resulting supernatant plasma was an almost pure (97.71 +/- 0.30%; n = 15) suspension of highly viable (98.72 +/- 0.28%) lymphocytes. When sodium citrate was used as an anticoagulant, lymphocyte suspensions collected in the same manner showed lower purity (87.89 +/- 1.59%; n = 9) and higher yields (56.56 +/- 3.89%, n = 9 versus 36.11 +/- 2.23%, n = 15). Where needed, a further centrifugation at 250 xg for 3 min (r.t.) of heparinized lymphocyte preparations removed an average of 87.39% (n = 15) contaminating platelets. A suspension of 85.96 +/- 2.20% pure granulocytes (93.23 +/- 1.74% neutrophils; n = 14) with minimal contamination by erythrocytes and high viability (93.11 +/- 1.26%) was obtained by performing a flash red blood cell lysis on the white-greyish layer resulting from the centrifugation of the heparinized blood samples. Among the several methods available, the procedure described herein is easy, rapid, cheap and reproducible.  相似文献   

Risk factors for stillbirths in two swine farms in the south of Brazil     

Lucia T  Corrêa MN  Deschamps JC  Bianchi I  Donin MA  Machado AC  Meincke W  Matheus JE 《Preventive veterinary medicine》2002,53(4):57-292

We evaluated stillbirth risk factors in two commercial swine farms of the Rio Grande do Sul State (south of Brazil). The study was conducted during 1 month in Farm A and during 2 months in Farm B, both during 1999. Data for all farrowings that occurred during the study period were recorded (101 for Farm A and 373 for Farm B), without interference in the farm management. In Farm A, 39% of all litters born during the period of interest had stillborn piglets and the stillborn risk for piglets was 12%. In Farm B, 25% of all litters had stillborn piglets whereas the stillborn risk was 2%. Variables considered as potential risk factors for stillbirths were: parity (1, 2–3, 4+); breed (purebred or crossbred); sow body-condition (normal or fat); use of oxytocin during parturition (yes or no); obstetric intervention through vaginal palpation (yes or no); farrowing duration (<4 or ≥4 h); mummified fetuses (yes or no); total litter size (<12 or ≥12 piglets); and litter birth weight (<11 or ≥11 kg). All stillborn piglets had their classification validated by necropsy. In multivariable logistic-regressions, the cases were the litters having at least one stillborn piglet. In Farm A, litters having at least 12 pigs and in which oxytocin was used during the parturition had 20.8-times-higher odds of stillborn occurrence. In Farm B, litters from sows having parity ≥4 had 2.2-times-higher odds of stillborn occurrence than litters from parity 2 to 3 females, litters having ≥12 pigs had 2.0-times-higher odds of a stillborn piglet than smaller litters and farrowings in which vaginal palpation was performed had 8.0-times-higher odds. Farrowing room management to minimize stillborn risk should target higher-parity females, large litters and optimization of practices of obstetric interventions.  相似文献   

Brucellosis in Brazil     

Poester FP  Gonçalves VS  Lage AP 《Veterinary microbiology》2002,90(1-4):55-62

This paper reviews the epidemiology of bovine, swine, ovine, caprine, and canine brucellosis in Brazil. The zoonotic aspects of Brucella infection in Brazil is also discussed. Emphasis is given to the new program for the control of brucellosis in cattle and buffaloes that is likely to provide important insights into the prospects and strategies for controlling brucellosis in developing countries.  相似文献   

Evaluation of the sensitivity of reverse-transcription polymerase chain reaction to detect porcine reproductive and respiratory syndrome virus on individual and pooled samples from boars.     

Albert Rovira  Travis Clement  Jane Christopher-Hennings  Bob Thompson  Mark Engle  Darwin Reicks  Claudia Mu?oz-Zanzi 《Journal of veterinary diagnostic investigation》2007,19(5):502-509

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Diet-associated hepatic failure and immune-mediated hemolytic anemia in a Weimaraner     

Ashley J. Smith  DVM    Katherine A. Stenske  DVM    Joseph W. Bartges  DVM  PhD  DACVIM  DACVN    Claudia A. Kirk  DVM  PhD  DACVN  DACVIM 《Journal of Veterinary Emergency and Critical Care》2006,16(S1):S42-S47

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Molecular systematics in Chrysanthemum × grandiflorum (Ramat.) Kitamura     

J. Chatterjee  A.K.A. Mandal  S.A. Ranade  Jaime A. Teixeira da Silva  S.K. Datta 《Scientia Horticulturae》2006

An attempt was made to understand the molecular systematics and genetic differences between 10 original chrysanthemum cultivars and 11 mutants. The similarity among the cultivars and mutants varied from 0.17 to 0.90 using RAPD analyses, a simple but efficient method to distinguish cultivars and to assess parentage. Two distinct groups were found. Two cultivars were present as a separate group showing differences from all other cultivars. Mutants with different flower colour could be identified at the molecular level using RAPD technique holding promise to identify unique genes as SCAR markers. A high genetic distance among the different chrysanthemums showed that there exists a possibility of introgressing new and novel genes from the chrysanthemum gene pool.  相似文献   

Effects of deficit irrigation strategies on cluster microclimate for improving fruit composition of Moscatel field-grown grapevines   总被引：1，自引：0，他引：1  

Tiago Pedreira dos Santos  Carlos M. Lopes  M. Lucília Rodrigues  Claudia R. de Souza  Jorge M. Ricardo-da-Silva  João P. Maroco  João S. Pereira  M. Manuela Chaves 《Scientia Horticulturae》2007

The grapevine plays a very important role in the economic, social and cultural sectors of many regions; however vineyards are often grown in regions under stressful conditions and thus they are vulnerable to climate change. The objective of this research was to investigate the effect of partial root-zone drying (PRD) irrigation on vine water relations, vegetative growth, plant microclimate, berry composition and yield components, compared to conventional deficit irrigation (DI, 50% ETc), full irrigation (FI, 100% of ETc) and non-irrigated vines (NI). The study was undertaken in mature ‘Moscatel’ grapevines (Vitis vinifera L.) grown in Pegões, South of Portugal. Compared to the other irrigated treatments, PRD vines showed a better microclimate at the cluster zone with higher incident photosynthetic photon flux density (PPFD). Within the more open canopies of NI and PRD treatments, berry temperatures were higher than those of denser ones (DI and FI). Compared to the conventional irrigation technique the better microclimate observed in PRD vines was a consequence of a reduction in vine growth, where lower values of leaf layer number, leaf area, canopy wideness, water shoots and shoot weight were observed. In PRD vines we observed a tendency to a development of a deeper root system, while DI and FI showed a more homogeneous root distribution throughout the different soil layers. PRD showed an improvement in berry quality with higher values of flavour precursors, and total phenols concentration without any significant yield reduction compared to DI and FI.  相似文献   

Improvements in somatic embryogenesis protocol in Feijoa (Acca sellowiana (Berg) Burret): Induction,conversion and synthetic seeds     

Gabriela Claudia Cangahuala-Inocente  Lírio Luiz Dal Vesco  Douglas Steinmacher  Antonio Carlos Torres  Miguel Pedro Guerra 《Scientia Horticulturae》2007

Pineapple guava (Acca sellowiana) syn. Feijoa sellowiana, a Brazilian indigenous Myrtaceae is under domestication in South Brazil. Previous works showed that this species is responsive to somatic embryogenesis and recalcitrant to conventional methods of clonal propagation. In the present work it was evaluated the role of components of culture medium in the induction and development of somatic embryos. The technology of synthetic seeds was also evaluated. Zygotic embryos were inoculated in LPm medium supplemented with 8 mM glutamic acid and 8 mM l-glutamine, 2,4-dichlophenoxiacetic acid (20 μM) and myo-inositol. For conversion of somatic embryos and synthetic seeds it was tested the effect of 6-benzylaminopurine and gibberellic acid combined or not with activated charcoal. The highest values for embryogenetic induction (100%) and number of somatic embryos/explant (113) were observed in the LPm medium supplemented with Glu (8 mM), and 2,4-D. The culture medium supplemented with BA (0.5 μM) and GA₃ (1 μM) and activated charcoal (1.5 g L⁻¹) enhanced the conversion of somatic embryos to plantlets. Pre-germinated somatic embryos encapsulated in sodium alginate with BA (0.5 μM) and GA₃ (1 μM) developed radicles. The use of synthetic seed was a requisite for the survival of plantlets.  相似文献   

Intestinal obstruction by stones in a turtle.          下载免费PDF全文

S C Rahal  C R Teixeira  G B Castro    L C Vulcano 《The Canadian veterinary journal. La revue veterinaire canadienne》1998,39(6):375-376

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