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51.
Reticuloendotheliosis (RE) in captive greater prairie chickens (GPC, Tympanuchus cupido pinnatus) and Attwater's prairie chickens (APC, Tympanuchus cupido attwateri) was first reported in 1998. RE is caused by avian reticuloendotheliosis virus (REV), an oncogenic and immunosuppressive retrovirus infecting multiple species of wild and domestic birds. During August 2004 through May 2006 a captive population of prairie chickens was affected simultaneously with a neoplastic condition and also avian pox, the latter being detected in 7.4% (2 of 27) of all birds submitted for histopathology. A survey for REV was conducted in order to examine its possible role in mortality observed primarily in juvenile and adult specimens of prairie chickens. The investigative procedures included postmortem examinations, histopathology, molecular detection, and virus isolation. In total, 57 Attwater's prairie chickens and two greater prairie chickens were included in the study. REV infection was diagnosed using virus isolation or polymerase chain reaction (PCR) or both in 59.5% (28 of 47) of blood samples and/or tumors from suspect birds. Lymphosarcomas were detected in the tissues of 37% (10 of 27) of the birds submitted for histopathology. Such lymphosarcomas suggestive of RE represented the most frequent morphologic diagnosis on histopathology among 27 separate submissions of naturally dead prairie chickens. Overall, REV was detected or RE diagnosed in 34 of 59 prairie chickens (57.62%). The average death age of all birds diagnosed with lymphosarcomas on histopathology was 2.2 yr, ranging from <1 to 4 yr. Although deaths associated with neoplasia occurred in males and females in equal proportions based on submissions, overall more males were diagnosed as REV infected or RE affected (16 males vs. 7 females, and 11 birds of undetermined gender). Reticuloendotheliosis virus was confirmed as a significant cause of mortality in captive prairie chickens. 相似文献
52.
Juliana DF Barbosa Viviane B Silva Péricles B Alves Giuseppe Gumina Roseli LC Santos Damião P Sousa Sócrates CH Cavalcanti 《Pest management science》2012,68(11):1478-1483
BACKGROUND: Dengue fever is a severe public health problem for several countries. In order to find effective larvicides to aid control programs, the structure‐activity relationships of eugenol derivatives against Aedes aegypti (Diptera: Culicidae) larvae were evaluated. Additionally, the composition and larvicidal activity of Syzygium aromaticum essential oil was assessed. RESULTS: Four compounds representing 99.05% of S. aromaticum essential oil have been identified. The essential oil was active against Ae. aegypti larvae (LC50 = 62.3 and 77.0 ppm, field‐collected and Rockefeller larvae respectively). The larvicidal activity of eugenol, the major compound of the essential oil, was further evaluated (LC50 = 93.3 and 71.9 ppm, field‐collected and Rockefeller larvae respectively). The larvicidal activity and structure‐activity relationships of synthetic derivatives of eugenol were also assessed. The larvicidal activity of the derivatives varied between 62.3 and 1614.9 ppm. Oxidation of eugenol allylic bond to a primary alcohol and removal of the phenolic proton resulted in decreased potency. However, oxidation of the same double bond in 1‐benzoate‐2‐methoxy‐4‐(2‐propen‐1‐yl)‐phenol resulted in increased potency. CONCLUSION: Structural characteristics were identified that may contribute to the understanding of the larvicidal activity of phenylpropanoids. The present approach may help future work in the search for larvicidal compounds. Copyright © 2012 Society of Chemical Industry 相似文献
53.
Fernando Brito Lopes Cláudio Ulhôa Magnabosco Mariana Márcia Mamede Marcelo Corrêa da Silva Eliane Sayuri Myiage Fernanda Paulini Raysildo Barbosa Lôbo 《Tropical animal health and production》2013,45(6):1375-1381
This study used multivariate statistics to identify clusters of animals with similar expected progeny difference (EPD) and also identify leading traits that discriminate between bulls. Various linear selection indices based on specific selection criteria were proposed. Records were collected from 880 young Nelore bulls submitted to performance testing in central Brazil between 2001 and 2012. Pre-weaning average daily gain and weights at 210 days with direct and maternal effects were used in the analysis, in addition to post-weaning weight, scrotal circumference at 365 and 450 days, carcass finish and rib eye area. EPDs were classified into three groups, and the EPD means of two of these groups stood out and were considered important based on principal component analysis that associated higher values of direct EPD of weights, average daily weight gain and scrotal circumference. The EPDs for weight at 210, 365 and 450 days, pre- and post-weaning daily gain and scrotal circumference at 365 and 450 days were major causes of variation. Each linear selection index proposed (SI1, SI2, SI3, SI4 and SI5) defined a specific approach meaning that a different selection index should be used depending on breeding goals and selection criteria. 相似文献
54.
Barbosa LC Pereira UA Teixeira RR Maltha CR Fernandes SA Forlani G 《Journal of agricultural and food chemistry》2008,56(20):9434-9440
The [4 + 3] cycloaddition of the proper furans with the oxyallyl cation, generated in situ from 2,4-dibromopentan-3-one, produced a series of 8-oxabicyclo [3.2.1]oct-6-en-3-ones. Exposure of the oxabicycles to ozone afforded the corresponding 8,9,10,11-tetraoxatricyclo[5.2.1.1 (2,6)]undecan-4-ones in variable yields (7-100%). The phytotoxic properties of these ozonides (or 1,2,4-trioxolanes) and their oxabicycle precursors were evaluated as the ability to interfere with the growth of Sorghum bicolor and Cucumis sativus seedlings. Among oxabicycles, the highest inhibitory activity was shown by compounds possessing a alpha,beta-unsaturated carbonyl moiety. A differential sensitivity of the two crops was evident with ozonides. The most active compounds were also tested against the weed species Ipomoea grandifolia and Brachiaria decumbens. To the best of our knowledge, this is the first article describing ozonides as potential herbicides. 相似文献
55.
Martin Bonamy Sabrina Kluska Elisa Peripolli Marcos Vinícius Antunes de Lemos Sabrina Thaise Amorim Roberto Jose Vaca Raysildo Barbosa Lbo Letícia Mendes de Castro Carina Ubirajara de Faria Fabio Borba Ferrari Fernando Baldi 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2019,136(1):15-22
The aim of this study was to estimate genetic parameters for different precocious calving criteria and their relationship with reproductive, growth, carcass and feed efficiency in Nellore cattle using the single‐step genomic BLUP. The reproductive traits used were probability of precocious calving (PPC) at 24 (PPC24), 26 (PPC26), 28 (PPC28) and 30 (PPC30) months of age, stayability (STAY) and scrotal circumference at 455 days of age (SC455). Growth traits such as weights at 240 (W240) and 455 (W455) days of age and adult weight (AW) were used. Rib eye area (REA), subcutaneous fat thickness (SFT), rump fat thickness (RFT) and residual feed intake (RFI) were included in the analyses. The estimation of genetic parameters was performed using a bi‐trait threshold model including genomic information in a single‐step approach. Heritability for PPC traits was moderate to high (0.29–0.56) with highest estimates for PPC24 (0.56) and PPC26 (0.50). Genetic correlation estimates between PPC and STAY weakened as a function of calving age. Correlation with SC455, growth and carcass traits were low (0.25–0.31; ?0.22 to 0.04; ?0.09 to 0.18, respectively), the same occurs with RFI (?0.09 to 0.08), this suggests independence between female sexual precocity and feed efficiency traits. The results of this study encourage the use of PPC traits in Nellore cattle because the selection for such trait would not have a negative impact on reproductive, growth, carcass and feed efficiency indicator traits. Stayability for sexual precocious heifers (PPC24 and PPC26) must be redefined to avoid incorrectly phenotype assignment. 相似文献
56.
Antibody phage display libraries are a useful tool in proteomic analyses. This study evaluated an antibody recombinant library for identification of sex-specific proteins on the sperm cell surface. The Griffin.1 library was used to produce phage antibodies capable of recognizing membrane proteins from Nelore sperm cells. After producing soluble monoclonal scFv, clones were screened on Simental sperm cells by flow cytometry and those that bound to 40–60% of cells were selected. These clones were re-analyzed using Nelore sperm cells and all clones bound to 40–60% of cells. Positive clones were submitted to a binding assay against male and female bovine leukocytes by flow cytometry and one clone preferentially bound to male cells. The results indicate that phage display antibodies are an alternative method for identification of molecules markers on sperm cells. 相似文献
57.
Comparison of serological assays for the diagnosis of canine visceral leishmaniasis in animals presenting different clinical manifestations 总被引:1,自引:0,他引:1
Ferreira Ede C de Lana M Carneiro M Reis AB Paes DV da Silva ES Schallig H Gontijo CM 《Veterinary parasitology》2007,146(3-4):235-241
Three serological methods, indirect fluorescent immunoassay (IFI), enzyme-linked immunosorbent assay (ELISA) and direct agglutination test (DAT) that are commonly employed in the diagnosis of canine visceral leishmaniasis (CVL), have been assessed. A total of 234 domestic dogs, drawn from an area in the municipality of Belo Horizonte, Minas Gerais, Brazil, endemic for visceral leishmaniasis, were submitted to clinical and parasitological examinations and serological assay. Sera collected from confirmed non-infected dogs (n=20), and from dogs with other parasitic diseases including Trypanosoma cruzi (n=7), Leishmania braziliensis (n=5), Toxoplasma gondii (n=5) and Ehrlichia canis (n=3), were also included in the study. IFI presented a lower sensitivity (72%) than ELISA (95%), although the specificities of these assays were low (52 and 64%, respectively) and both exhibited cross-reactivity with sera from dogs infected with T. cruzi, L. braziliensis and E. canis. In contrast, DAT exhibited a high sensitivity (93%) and a high specificity (95%) and cross-reacted with only one serum sample derived from an E. canis-infected dog. The reproducibilities of the ELISA and DAT assays were excellent, whilst that of IFI was considered to be acceptable. The results produced by ELISA and DAT were in complete agreement, those between ELISA and IFI were at an acceptable level of agreement, whilst the concurrence between the IFI and DAT results were either acceptable or poor depending on the clinical conditions of the group of dogs examined. Since there is no readily accessible method for the diagnosis of CVL that offers 100% specificity and sensitivity, the choice of technique employed must depend on the aim of the investigation. 相似文献
58.
Martha Reyes‐Becerril Dariel Tovar‐Ramírez Felipe Ascencio‐Valle Roberto Civera‐Cerecedo Vicente Gracia‐López Valérie Barbosa‐Solomieu María Ángeles Esteban 《Aquaculture Research》2011,42(11):1676-1686
Two trials were conducted to determine the efficacy of fish fed live yeast Debaryomyces hansenii strain CBS 8339 on immune and antioxidant systems in leopard grouper Mycteroperca rosacea infected with Aeromonas hydrophila. Juveniles (12±0.5 g) were fed with a control diet or a D. hansenii‐supplemented diet (106 colony‐forming units per gram) for 5 weeks. The live weight of fish was registered on a weekly basis. After 4 weeks, fish from each treatment were immunocompromised with pathogenic A. hydrophila and further fed for 1 week in order to evaluate the effect on immunological and antioxidant parameters. Generally, the results showed enhanced growth performance in fish fed the diet containing yeast compared with the control. Addition of live yeast had no significant effect on the immunological parameters after 4 weeks of feeding. However, post infection with A. hydrophila fish fed the yeast‐supplemented diet resulted in a significant increase in the levels of plasmatic immunoglobulin M. Superoxide dismutase and catalase (CAT) activities were significantly higher in the yeast group. In this fish, CAT and heat shock protein 70 genes were up‐regulated before and after infection of A. hydrophila. The present study is the first one reporting that yeast (D. hansenii) can enhance immunity and resistance against A. hydrophila. 相似文献
59.
Vanderlúcia F de Paula Luiz C de A Barbosa Antnio J Demuner Dorila Pil‐Veloso Marcelo C Picano 《Pest management science》2000,56(2):168-174
The natural lipophilic amides piperine and piperiline were isolated from Piper nigrum L (Piperaceae). Piperine was hydrolysed into piperic acid (85% yield) which was converted into 16 amides (28–89% yield). The contact toxicity of all synthetic amides, and also that of piperine and piperiline, at the dose 10 µg per insect, was evaluated for the Brazilian economically important insects Ascia monuste orseis Latr, Acanthoscelides obtectus Say, Brevicoryne brassicae L, Protopolybia exigua DeSaus and Cornitermes cumulans Kollar. The results demontrated that the insects have different sensivities to the various amides, with mortality ranging from 0 to 97.5% according to the compound and insect species. © 2000 Society of Chemical Industry 相似文献
60.