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991.
de Siqueira-Silva Diógenes Henrique dos Santos Silva Amanda Pereira da Silva Costa Raphael Senhorini José Augusto Ninhaus-Silveira Alexandre Veríssimo-Silveira Rosicleire 《Fish physiology and biochemistry》2021,47(3):767-776
Fish Physiology and Biochemistry - We aimed to develop a simplified protocol for transplantation of Brycon orbignyanus spermatogonial stem cells (SSCs) into Astyanax altiparanae testes. Brycon... 相似文献
992.
Toxicity of insecticides to the sweetpotato whitefly (Hemiptera: Aleyrodidae) and its natural enemies 总被引:1,自引:0,他引:1
Bacci L Crespo AL Galvan TL Pereira EJ Picanço MC Silva GA Chediak M 《Pest management science》2007,63(7):699-706
Efficient chemical control is achieved when insecticides are active against insect pests and safe to natural enemies. In this study, the toxicity of 17 insecticides to the sweetpotato whitefly, Bemisia tabaci (Gennadius), and the selectivity of seven insecticides to natural enemies of this insect pest were evaluated. To determine the insecticide toxicity, B. tabaci adults were exposed to abamectin, acephate, acetamiprid, cartap, imidacloprid, malathion, methamidophos, bifenthrin, cypermethrin, deltamethrin, esfenvalerate, fenitrothion, fenpropathrin, fenthion, phenthoate, permethrin and trichlorphon at 50 and 100% of the field rate (FR), and to water (untreated control). To determine the insecticide selectivity, adults of Encarsia sp., Acanthinus sp., Discodon sp. and Lasiochilus sp. were exposed to abamectin, acephate, acetamiprid, cartap, imidacloprid, malathion and methamidophos at 50 and 100% FR, and to water. Groups of each insect species were exposed to kale leaves preimmersed in each treatment under laboratory conditions. Mortality of exposed individuals was recorded 24 h after treatment. Cartap and imidacloprid at 50 and 100% FR and abamectin and acetamiprid at 100% FR showed insecticidal activity to B. tabaci adults. Abamectin at 50 and 100% FR was the least insecticidal compound to the natural enemies Acanthinus sp., Discodon sp. and Lasiochilus sp. The present results suggest that abamectin at 100% FR may decrease B. tabaci field populations but can still be harmless to predators. Implications of these results within an integrated pest management context are discussed. 相似文献
993.
Thompson JA de Miranda Henriques Leite R Gonçalves VS Leite RC Bandeira DA Herrmann GP Moreira EC Prado PE Lobato ZI de Brito CP Lage AP 《Preventive veterinary medicine》2006,76(3-4):290-301
We estimated spatial hierarchal variances and age-group covariances for seroprevalence to Leptospira interrogans serovar hardjo (LeptoH), bovine viral-diarrhea virus (BVDV) and bovine herpesvirus type 1 (BoHV-1) among 2343 cattle from 72 properties sampled in the State of Paraíba, Brazil in 2000. From each property, eight animals in each of the four age categories were evaluated. The age categories studied were: pre-weaned (0–6 months), young (7–18 months), replacement (19–30 months) and mature (>30 months). Overall seroprevalence to LeptoH was 16.0% and showed clustering at all levels of the spatial hierarchy and had a high posterior probability of being negatively correlated between replacement and mature groups within herds. Seroprevalence to BoHV-1 was 46.6% and demonstrated very little clustering among levels of the spatial hierarchy and was positively correlated between young and replacement groups within herds. Seroprevalence to BVD was 22.2% and was strongly clustered within herds and was positively correlated between young and replacement age groups within herds. 相似文献
994.
Over a period of 12 years, from 1988 to 2000, a total of 20 individual equines (16 horses and 4 mules) were selected at random, from 10 municipalities in the Paraíba Valley, in the State of São Paulo, Brazil, and then subjected to necropsy for collection of gastrointestinal worms. Individual samples of 10% of the intestinal contents were also taken for counting and identifying the species present, and to establish the prevalence of worms in equine species in the Paraíba Valley. In the sample considered, the presence of parasites ranged from 155 to 1249 worms. Tapeworms (Cestoidea) were present in about 85% of the animals studied, and roundworms (Nematoda) in 100% of the individuals. All the tapeworms collected were of one single species, Anoplocephala perfoliata. In the case of the roundworms, the prevalence of individual species was: 100% for Cyathostomineae, 90% for Oxyuris equi, 70% for Strongylus vulgaris, 45% for S. edentatus, 15% for Strongylus equinus, 60% for Triodontophorus sp., 50% for Gyalocephalus capitatus, 15% for Oesophagodontus robustus and Craterostomum acuticaudatum, and 5% each for Parascaris equorum, Probstimayria vivipara, Habronema muscae, and Trichostrongylus axei. No specimens of flukes (Trematoda) were found in any of the animals studied. 相似文献
995.
João A Pereira MA Cortes S Santos-Gomes GM 《Journal of veterinary medicine. A, Physiology, pathology, clinical medicine》2006,53(10):540-545
The aim of this study was to investigate whether treatment against canine leishmaniasis reduced the presence of Leishmania in the healthy skin of dogs, affecting the capacity of parasite transmission. A total of 37 dogs from an endemic region of leishmaniasis were studied. Thirteen symptomatic animals revealed parasites in the bone marrow and eight had also in the skin. Five of the 22 dogs that had been treated with meglumine antimoniate alone, meglumine antimoniate or trifluralin followed by allopurinol or just with allopurinol had the parasite in bone marrow but none showed Leishmania in the skin. One dog that was treated only with aminosidine was polisymptomatic and had parasites in bone marrow and skin. The different treatments used in this study did not completely eliminate the parasite allowing relapses to occur when the treatment is discontinued, but the use of meglumine antimoniate or allopurinol, alone or combined may improve dogs clinical condition and reduce or eliminate the parasite from the skin decreasing the probability of Leishmania transmission. 相似文献
996.
Luciana Lasry Benchimol Tatiana de Campos Sérgio Augusto Morais Carbonell Carlos Augusto Colombo Alisson Fernando Chioratto Eduardo Fernandes Formighieri Lígia Regina Lima Gouvêa Anete Pereira de Souza 《Genetic Resources and Crop Evolution》2007,54(8):1861-1762
A common bean genomic library was constructed using the ‘IAC-UNA’ variety enriched for (CT) and (GT) for microsatellite motifs.
From 1,209 sequenced clones, 714 showed microsatellites distributed over 471 simple and 243 compound motifs. GA/CT and GT/CA
were the most frequent motifs found among these sequences. A total of 123 microsatellites has been characterized. Out of these,
87 were polymorphic (73.7%), 33 monomorphic (26.8%), and 3 (2.4%) did not amplify at all. In a sample of 20 common bean materials
selected from the Agronomic Institute Germplasm Bank, the number of alleles per locus varied 2–9, with an average of 2.82.
The polymorphic information content (PIC) of each marker varied from 0.05 to 0.83, with a 0.45 average value. Cluster and
principal coordinate analysis of the microsatellite data were consistent with the original assignment of the germplasm accessions
into the Andean and Mesoamerican gene pools of common bean. Low polymorphism levels detected could be associated with the
domestication process. These microsatellites could be a valuable resource for the bean community because of their use as new
markers for genetic studies.
Electronic supplementary material The online version of this article (doi: ) contains supplementary material, which is available to authorized users.
An erratum to this article can be found at 相似文献
997.
The effects of pH and ionic strength on the release of Hg from contaminated coastal sediments to water were evaluated in a
series of laboratory experiments. Data show that the higher the ionic strength and the pH the smaller is the amount of Hg
desorbed into solutions. The effect of the ionic strength on the leaching of Hg from contaminated sediments is more evident
for values lower than 0.4 mol dm−3, while the influence of pH becomes more pronounced for values lower than 7. Based on qualitative concepts from colloid chemistry
an attempt is made to provide an explanation of the observed results. 相似文献
998.
Franco L SouzaAnderson F Cunha Marcos A OliveiraGonçalo A.G Pereira Hildete P PinheiroSérgio F dos Reis 《Biological conservation》2002,104(1):119-126
Hydromedusa maximiliani is a vulnerable freshwater turtle endemic to mountainous regions of the Atlantic rainforest in southeastern Brazil. Random amplified polymorphic DNA (RAPD) were surveyed with the purpose of assessing the genetic structure and determining the partitioning of molecular variation in H. maximiliani across the natural spatial hierarchical scale of its habitat. The goal of the study was to integrate ecological data with estimates of molecular genetics diversity to develop strategies for the conservation of this freshwater turtle. Specimens were sampled from rivers and streams across three drainages. Nine of the 80 primers used generated 27 scoreable bands of which 10 (37%) were polymorphic and produced 16 RAPD phenotypes. Significant heterogeneity was found in the distribution of RAPD molecular phenotypes across the three drainages. Analysis of molecular variance for molecular phenotypes showed that the heterogeneity had a spatial structure since a significant amount (22%) of the total variance was attributable to variation among rivers and streams. Since the genetic variation of this turtle seems to be structured according to the natural hierarchical system of rivers and streams within drainages, it is suggested that local populations should be considered as separate management units. 相似文献
999.
Annibal D. Pereira Netto Thomas M. Krauss Issaranã F. Cunha Eliane C. P. Rego 《Water, air, and soil pollution》2006,176(1-4):57-67
Polycyclic aromatic hydrocarbons (PAHs) were studied in street dust (SD) samples collected in the center of Niterói, a tropical city located in the State of Rio de Janeiro, Brazil, at the margins of Guanabara Bay. Sampling was carried out monthly during the year of 2002 in order to evaluate seasonal variation of PAH concentrations. Samples were extracted by ultrasonic treatment with dichloromethane, cleaned up by solid phase extraction and analyzed by gas chromatography-mass spectrometry. The concentrations of the twenty one analyzed PAHs ranged from 3.2 to 132 ng/g. Of all PAHs, pyrene, fluoranthene and naphthalene showed the highest geometric means. Total PAH concentration (σPAH) ranged from 434 to 1247 ng/g with levels of carcinogenic PAHs (σCARC) representing 29 to 45% of σPAHs. The highest value of σPAH occurred in July 2002, when the lowest temperatures were measured in the Central Area of Niterói City. σPAH and σCARC showed significant correlations with daily mean and minimum temperature, as well as with temperature during sampling, indicating that both are influenced by these parameters. The obtained results suggest that a seasonal variation of total PAH levels in SD may occur in the studied area. 相似文献
1000.
Jeana Pereira da Silva Sheila Canevese Rahal Maria Cristina Reis Castiglioni Luna Scarpari Rolim Whítara Ferreira Lima Bruno Cesar Schimming Anneke Moresco Maria Jaqueline Mamprim 《Anatomia, histologia, embryologia》2021,50(6):940-946
Baseline data for wall thickness in healthy toucans can be used to diagnose disease in sick individuals. This study aimed to evaluate the use of ultrasonography for the examination of the gastrointestinal tract of healthy toco toucans (Ramphastos toco). Ten non-anaesthetized healthy adult toco toucans were evaluated. Food was withheld for 3 h prior to the ultrasound examination. Longitudinal and transverse images of the gastrointestinal tract were obtained using ventromedian cranial and ventromedian caudal approaches to evaluate the morphology and stratification. The wall thickness of the sections was measured: proventriculus and ventriculus, duodenum, jejunum/ileum, and cloaca. Additionally, the thickness of the mucosal layer of the duodenum and jejunum/ileum was also measured. Subsequently, the ratios of the duodenal wall thickness to the duodenal mucosa layer and the total wall thickness of the jejunum/ileum to the jejunum/ileum layer mucosa were stablished. The wall thickness of the proventriculus was significantly higher than the wall thickness of ventriculus. The wall thickness of the duodenum was significantly higher than the wall thickness of jejunum/ileum. The mean ratios of the duodenal wall thickness to the duodenal mucosa layer and the wall thickness of the jejunum/ileum to the jejunum/ileum layer were 83.15% and 80.07%, respectively. In conclusion, it was possible to assess the stomach and intestines using ultrasound examination in healthy toco toucans, due to their medium body size and no interference by surrounding air sacs. 相似文献