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921.
Larvicidal and residual activity of imidazolium salts against Aedes aegypti (Diptera: Culicidae) 下载免费PDF全文
Emanuelle Goellner Ademir Tramontini Schmitt Júlia Lacerda Couto Nicolas Drumm Müller Harry Luiz Pilz‐Junior Henri Stephan Schrekker Carlos Eugenio Silva Onilda Santos da Silva 《Pest management science》2018,74(4):1013-1019
BACKGROUND
Aedes aegypti is an important mosquito species that can transmit several arboviruses such as dengue fever, yellow fever, chikungunya and zika. Because these mosquitoes are becoming resistant to most chemical insecticides used around the world, studies with new larvicides should be prioritized. Based on the known biological profile of imidazolium salts (IS), the objective of this study was to evaluate the potential of six IS as larvicides against Ae. aegypti, as tested against Ae. aegypti larvae. Larval mortality was measured after 24 and 48 h, and residual larvicidal activity was also evaluated.RESULTS
Promising results were obtained with aqueous solutions of two IS: 1‐n‐octadecyl‐3‐methylimidazolium chloride ( C 18 MImCl ) and 1‐n‐hexadecyl‐3‐methylimidazolium methanesulfonate ( C 16 MImMeS ), showing up to 90% larval mortality after 48 h exposure. C 18 MImCl was more effective than C 16 mIMeS , causing mortality until day 15 after exposure. An application of C 18 MImCl left to dry under ambient conditions for at least 2 months and then dissolved in water showed a more pronounced residual effect (36 days with 95% mortality and 80% mortality up to 78 days).CONCLUSION
This is the first study to show the potential of IS in the control of Ae. aegypti. Further studies are needed to understand the mode of action of these compounds in the biological development of this mosquito species. © 2017 Society of Chemical Industry922.
The effect of varying dietary digestible protein and digestible non‐protein energy sources on growth,nutrient utilization efficiencies and body composition of carp (Cyprinus carpio) evaluated with a two‐factorial central composite study design 下载免费PDF全文
To determine optimized dietary nutrient supply for common carp (Cyprinus carpio), nine isoenergetic diets were formulated according to a two‐factorial central composite design on digestible basis. Digestible protein contents (DP) in diets ranged from 208.8 to 251.2 g/kg, and digestible fat‐to‐digestible carbohydrate energy ratios (DEF/DEC) varied from 0.79 to 1.21. Carp were fed four times a day at a daily feeding rate of 2.5 g/kg body weight for 56 days. Optima of responses were determined by applying the standard least squares method according to response surface methodology. All diets resulted in excellent performance with feed conversion ratios lower than 1 and digestible protein efficiency ratios (PERdig) higher than 4.6. For most parameters, calculated extreme values were minimum points, except for FCR, retention efficiencies of digestible arginine (RetArgdig) and of digestible methionine (RetMetdig), being maximum points, and retention efficiencies of digestible isoleucine, digestible sulphuric amino acids and digestible lysine, being saddle points. Highest growth and feed utilization efficiency were graphically determined for a diet containing 208.8 g/kg DP/1.21 DEF/DEC. Body lipid was optically increased for 251.2 g/kg DP/0.79 DEF/DEC in comparison with 208.8 g/kg DP/1.21 DEF/DEC. 相似文献
923.
da Silva Fialho L Guimarães VM de Barros EG Moreira MA Dos Santos Dias LA de Almeida Oliveira MG José IC de Rezende ST 《Plant foods for human nutrition (Dordrecht, Netherlands)》2006,61(2):87-89
Common beans have a high nutritional value, but contain galactooligosaccharides (GO), which cause flatulence and intestinal discomfort in humans. The biochemical composition of ten bean cultivars was determined to select those of high protein and low GO contents. The cultivars varied in carbohydrate (47.02-60.17%), GO (3.12-5.71%), protein (22.17-33.50%), lipid (1.13-1.81%), moisture (11.42-12.93%) and ash contents (4.08-5.61%). 'Mexico 222' presented the highest alpha-galactosidase activity. Protein and GO contents were positively correlated. 'Perry Marrow' combined high protein and low GO concentrations, indicating it can be used in improvement programs aiming at high-quality cultivars for human consumption. 相似文献
924.
Phylogeny,distribution and pathogenicity of Lasiodiplodia species associated with dieback of table grape in the main Brazilian exporting region 下载免费PDF全文
K. C. Correia M. A. Silva M. A. de Morais Jr J. Armengol A. J. L. Phillips M. P. S. Câmara S. J. Michereff 《Plant pathology》2016,65(1):92-103
Botryosphaeria dieback is an important disease of table grape in the São Francisco Valley, the main Brazilian exporting region. The objectives of this study were to identify species of Lasiodiplodia associated with botryosphaeria dieback of table grapes in the São Francisco Valley, investigate the prevalence and distribution of the species in the region, and evaluate their pathogenicity and virulence in green shoots of table grape. A total of 112 Lasiodiplodia isolates were obtained from 14 vineyards, located in Casa Nova, Juazeiro and Petrolina. Fungal identifications were made using phylogenetic analysis based on partial sequences of translation elongation factor 1‐α (EF1‐α) and internal transcribed spacer (ITS) sequences, in combination with morphometric characteristics of conidia. Eight species of Lasiodiplodia were identified: L. brasiliense, L. crassispora, L. egyptiacae, L. euphorbicola, L. hormozganensis, L. jatrophicola, L. pseudotheobromae and L. theobromae. Except for L. crassispora, L. pseudotheobromae and L. theobromae, all the other species are reported for the first time on grapevine worldwide. The distribution of Lasiodiplodia species differed between the three table grape populations of São Francisco Valley. All Lasiodiplodia species isolated in this study were present in the population of Casa Nova and Lasiodiplodia theobromae was the most prevalent. All species of Lasiodiplodia were pathogenic on detached green shoots of grapevine, with L. brasiliense being the most virulent. 相似文献
925.
Adriano Carvalho Costa Hortência Aparecida Botelho Richardson Cesar da Silva Gomes Sergio Augusto de Sousa Campos Rafael Vilhena Reis Neto Marcio Balestre Fernanda Dotti do Prado Diogo Teruo Hashimoto Diego Galetti Martins Fbio Porto‐Foresti Mrio Lima Rilke Tadeu Fonseca de Freitas 《Aquaculture Research》2019,50(3):717-724
This work was carried out to predict the combining abilities, both general and specific, for performance traits and bodily yields of Serrasalmidae. Ninety‐six 30‐day‐old juveniles were purchased from two commercial fish farms, 12 of each of the following eight genetic groups: pacu, pirapitinga, tambaqui, tambacu, tambatinga, patinga, paqui and piraqui. Six fish from each genetic group were grown in 500‐L fibreglass tanks (two tanks per genetic group) until they were 495 days old. At the end of the growth period fish were weighed, subjected to morphometric analysis and processed to obtain their bodily yields. Two nuclear markers and one mitochondrial marker were used to confirm the identity of the animals. Combining abilities were obtained using the method proposed by Griffing in 1956 (Australian Journal of Biological Science, 4, 463–493) adapted to a mixed models analysis, environmental effects were estimated by the empirical best linear unbiased estimator method and genetic effects (general and specific combining abilities) were estimated with the empirical best linear unbiased predictor. Predictions of the combining abilities of advanced hybrids were obtained by the mixed models mixture method with normal distributions. Tambaqui showed higher general and specific combining abilities than the other groups for most of the variables, making it the most important genetic group. General combining ability makes a greater contribution to phenotypic variance than specific combining ability for most variables, indicating a predominance of genes with an additive effect in the control of evaluated traits. 相似文献
926.
Seixas A Oliveira P Termignoni C Logullo C Masuda A da Silva Vaz I 《Veterinary immunology and immunopathology》2012,148(1-2):149-156
Rhipicephalus (Boophilus) microplus is one of the most widely distributed tick in the world. The control of the parasite is based mainly on the use of chemical acaricides, which are produced from a limited set of molecules. These drugs induce selection of acaricide-resistant ticks, and are an important source of environmental pollution. An approach based on anti-tick vaccines may circumvent these obstacles. Characterization of the physiological function of tick molecules may be useful to develop new vaccines. Previously, we reported the ability of some tick proteins as inducers of protective immune response. Vaccination studies using tick proteins like native (nBYC), recombinant (rBYC) egg-yolk aspartic endopeptidase and cysteine endopeptidase (VTDCE) from R. microplus and glutathione S-transferase (Hl-GST) from Haemaphysalis longicornis demonstrated the immunogenicity and antigenicity of these proteins in bovines. Eventually, immunization with these proteins triggered a partial immune response against R. microplus infestation in cattle, manifested mainly as a reduction in egg fertility (7.7% and 13.9% for nBYC, 5.9% for rBYC; 4.7% for VTDCE, 7.9% for Hl-GST), and in the number of fully engorged ticks (18.2% for rBYC, 14.6% for VTDCE, 53% for Hl-GST). The data so far obtained suggest that these proteins have potential to be used as antigens in an anti-tick vaccine. Other proteins involved in tick embryogenesis also have this potential, like THAP and BmCl1, which are enzymes with key roles in vitellin and hemoglobin hydrolysis. Moreover, the identification of analogous proteins present in other tick species may bring information about the way to develop a vaccine against multiple tick species which can help to solve the problem faced by numerous countries where animals are parasitized by more than one tick species. The aim of the present review is to comprehensibly summarize the data obtained in the last few years by our collaborative research, discussing the efforts we have made to find antigens efficient enough for a cattle tick-controlling vaccine. This review discusses tick physiology studies aimed at the selection of possible targets, characterization of the selected proteins with emphasis on their biochemical and immunological aspects and results of vaccine trials on bovines. 相似文献
927.
Weber K Ernst R Fankhauser H Hardisty JF Heider W Stevens K 《Journal of toxicologic pathology》2009,22(4):247-254
Thyroid dysplasia was recognized in WistarHan GALAS rats and confirmed as a heritable congenital disorder. The gene or genes involved were not identified, but homozygous animals with thyroid dysplasia also exhibited stunted growth, had reduced pituitary gland growth hormone (GH) and were hypothyroid. Heterozygous animals exhibited thyroid dysplasia with normal thyroid hormonal homeostasis and no difference in the incidence of preneoplastic or neoplastic lesions in oncogenicity studies. 相似文献
928.
Ramos CA Araújo FR Souza II Bacanelli G Luiz HL Russi LS Oliveira RH Soares CO Rosinha GM Alves LC 《Veterinary parasitology》2011,176(1):79-83
This paper reports a quantitative real-time polymerase chain reaction (q-PCR) based on the msa2c gene and standardized with Platinum SYBR Green/ROX for the detection of Babesia bovis in cattle. The msa2c q-PCR amplified a DNA fragment with average dissociation temperature of 77.41°C (± 0.25°C). No amplification was detected when DNA from B. bigemina, A. marginale or Bos taurus was used as the template. The detection limit of the msa2c q-PCR was 1000 copies per ml of blood sample, with a linear correlation between the number of msa2c copies and threshold cycle. The comparison between msa2c q-PCR and conventional PCR for cytochrome b revealed 88.8% agreement, with a Kappa index of 0.75. In the comparison between msa2c q-PCR and an enzyme-linked immunosorbent assay (ELISA) with semi-purified B. bovis antigen, agreement was 96.3% and the Kappa index was 0.91. The agreement between three tests was 85.8%. The msa2c q-PCR detected a higher number of positive cattle than conventional PCR in an enzootically stable area, but did not differ significantly from ELISA. No significant differences were detected between the three diagnostic tests with cattle from an enzootically unstable area. All animals raised on a tick-free facility were negative for B. bovis in the three tests. These results suggest that msa2c q-PCR is a useful test for the detection of B. bovis infection. 相似文献
929.
Lage IN Paulino PV Pires CV Villela SD Duarte Mde S Valadares Filho Sde C Paulino MF Maia BA Silva LH Teixeira CR 《Tropical animal health and production》2012,44(2):361-367
The performance, intake, feed efficiency, and carcass traits of beef cattle from different gender profile were assessed. Fifteen
animals (five steers, five spayed heifers, and five intact heifers) with ±250 kg of initial body weight were randomly assigned
in individual pens and fed the same diet for 106 days. At the end of the trial, all the animals were slaughtered and the pH,
temperature, and weight of the carcass were recorded. The right side of each carcass was then separated into chuck, shoulder,
flank sirloin, and round for evaluation of commercial cuts yield. The left carcass sides were ribbed between the 12th and
13th ribs where the rib eye area and fat thickness measurements were taken. The 9th–11th rib section was removed from the
left half carcass and then dissected into muscle, fat, and bones in order to estimate carcass composition. Gender had no effect
(P > 0.05) on performance, intake, digestibility of dry matter and all the nutrients evaluated, feed efficiency, and carcass
characteristics. It can be concluded that steers and heifers (spayed or not) have the same potential to produce beef. From
a productive and welfare standpoint, there is no reason to spay heifers. 相似文献
930.
Purdie AC Plain KM Begg DJ de Silva K Whittington RJ 《Comparative immunology, microbiology and infectious diseases》2012,35(2):151-162
The primary objective of this study was to evaluate early gene expression profiles associated with paratuberculosis in cattle exposed to known infectious doses of Mycobacterium avium sub-species paratuberculosis (MAP). A Johne's disease experimental infection field trial was conducted on a mixed population of Holstein and Holstein Red cattle. Blood samples from four MAP exposed and four unexposed cattle, selected based on IFNγ expressions were taken at 9, 13 and 21 weeks and RNA processed to Affymetrix GeneChip? Bovine Genome arrays. Ontological analysis revealed consistent differences in gene expression between MAP exposed and control animals. A stark variation was observed in expression of a number of genes along antigen presentation pathways, suggesting that MAP exposure potentially results in the host immune response switching to a CD8(+) biased antigen presentation profile. This requires further in-depth analysis since it exposes a hitherto unconfirmed association between MAP exposure and in vivo MHC gene modulation. 相似文献