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41.
42.
Andreotti R Oliveira JM Silva EA Oshiro LM Matos Mde F 《Veterinary parasitology》2006,135(3-4):375-379
Neospora caninum is an obligate intracellular protozoan that can infect domestic and wild canids, as well as ruminants and equines, and is described as causing neuromuscular alteration and death in dogs. Visceral leishmaniasis (VL) is an infectious disease that affects both humans and animals, being caused by protozoan parasites of the genus Leishmania, of which Leishmania (Leishmania) chagasi is found in Brazil -- transmitted by sand flies, such as Lutzomyia longipalpis, in most of the American continent. The immunosuppression caused by VL can promote the occurrence of co-infections with other agents. In order to determine the frequency of N. caninum and its relationship to VL in Campo Grande, MS, Brazil, 345 blood sera were collected from dogs. The sera were submitted to an indirect fluorescent antibody test (IFAT) for detection of anti-N. caninum antibodies and VL antibodies. N. caninum was found in 26.5% of VL-negative dogs and in 29% of VL-positive ones. Among males, it was found in 30.7% of VL-negative animals and in 30.4% of VL-positive ones; among females, in 21% of VL-negative animals and in 27.7% of VL-positive ones. Among juvenile dogs (under 1 year), N. caninum was detected in 10.5% of VL-negative animals and in 11.2% of VL-positive ones. For adult dogs (1 year and older) the results were 31.4% for VL-negative animals and 28.8% of VL-positive ones. The study revealed a statistically significant association with age (chi(2)=9.76, P<0.05) in the N. caninum results for VL-negative animals. No significant correlation in N. caninum seroprevalence was found when VL-positive or VL-negative dogs were compared (chi(2)=0.21, P=0.64). The findings suggest that in Campo Grande N. caninum and VL co-infection is common in dogs, though VL does not appear to enhance susceptibility to N. caninum. 相似文献
43.
Cochliomyia hominivorax (Calliphoridae) is one of the most important myiasis-causing flies and is responsible for severe economic losses to the livestock industry throughout the Neotropical region. In Brazil, C. hominivorax has been controlled mainly with organophosphate (OP) insecticides, although the inappropriate use of these chemicals can result in the selection of resistant flies. Changes in carboxylesterase activity have been associated with OP insecticides in some arthopodan species. In this work, we isolated and characterized part of the E3 gene in C. hominivorax (ChE7), which contained the same substitutions responsible for the acquisition of OP hydrolase activity in Lucilia cuprina (Calliphoridae). Digestion of the polymerase chain reaction products with a restriction enzyme that specifically recognized the mutation site unambiguously differentiated wild and mutated esterase alleles. The PCR-RFLP assay therefore provided a fast, reliable DNA-based method for identifying C. hominivorax individuals with a mutation in the esterase gene. Further bioassays to determine the association of this mutation with OP resistance in C. hominivorax should allow the development of more effective strategies for managing this species. 相似文献
44.
玄关是一个家距离外界最近的地方,也是打开房门后视线的第一个落点。如果玄关设计得体,既能为返家时刻增添愉悦心情,也能让客人对你的家一见倾心。 相似文献
45.
Structural development of Pacific red snapper Lutjanus peru from hatching to the onset of first feeding 下载免费PDF全文
Iram Zavala‐Leal Silvie Dumas Edgar O. López‐Villegas Renato Peña Mauricio Contreras‐Olguín Laura Flores‐Montijo José De La Cruz‐Agüero 《Aquaculture Research》2015,46(5):1162-1174
Successful rearing of larval fish requires culture conditions and feeding strategies matching the ontogenetic status of larvae. This study describes the external morphology and development of organs and structures involved in the feeding process (i.e. sensorial organs, mouthparts and digestive system) from hatching until first feeding in Pacific red snapper. Hatching occurred 26 h after fertilization at 26°C and total length (TL) was 2.45 ± 0.08 mm. The larvae showed an undifferentiated eye and digestive tract. At 48 hah, TL was 3.31 ± 0.12 mm. Yolk and oil globule were still present. The mouth was still closed, but the Meckel's, quadrate, hyoid and hyomandibular cartilages were present. The retina was formed by 5 layers, and a thin layer of pigment epithelium was observed in the outer nuclear layer (ONL). At 70 hah, TL was 3.44 ± 0.22 mm. A remnant of oil globule was still present. The mouth and anus were open. At 93 hah, the number of cones in the ONL of the retina have increased and there was more pigment in the pigment epithelial layer. A joint between Meckel's and the quadrate cartilage and also a joint between the hyomandibular cartilage and the skull were present. The presence of live feed was detected in the digestive tract of these larvae. Based on these observations, the Pacific red snapper larvae is functional to start ingesting live feed between the 3rd and 4th day after hatching. 相似文献
46.
Marcus André Ribeiro Correia Renato de Mello Prado Willian Natale Danilo Eduardo Rozane Diego Wyllyam do Vale 《Communications in Soil Science and Plant Analysis》2018,49(8):903-912
Soil acidity is one of the most important factors limiting crop production. The objective of this work was to evaluate the effects of limestone application on the soil chemical properties, nutrition and yield of mango plants in an orchard under implementation. The design was randomized blocks, with five limestone doses (0; 2; 4; 6 and 8 t ha?1) and four replications. Soil chemical analyses were performed (at 12, 24, 36 and 48 months after the experiment implementation) in the layers 0–20; 20–40 and 40–60 cm deep. Nutrition status and yield were assessed during the first and second crop seasons. The highest fruit yield was associated with the application of 3.9 and 3.8 t ha?1 of limestone in the 2008/09 and 2009/10 seasons, respectively, that is, the dose recommended by the literature for raising base saturation to 80%, as a function of the fertility conditions of the soil initially obtained. 相似文献
47.
Vinicius de Abreu D’Ávila Elen de Lima Aguiar-Menezes Renato Nunes Pereira Vânia Gonçalves-Esteves Cláudia Barbieri Ferreira Mendonça Saulo José de Melo Tamires Medeiros dos Santos 《Phytoparasitica》2017,45(4):471-484
Coleomegilla maculata DeGeer is an omnivorous lady beetle that feeds on natural or alternative prey and artificial foods, which allows its laboratory rearing for use on augmentative biocontrol. In addition, C. maculata may supplement its diet with pollen and nectar, which helps in its conservation in agroecosystems. This study aimed to evaluate if Apiaceous flowers (Anethum graveolens L. and Coriadrum sativum L.), with and without alternative prey [eggs of Ephestia kuehniella (Zeller) or larvae of Drosophila melanogaster Meigen] or an artificial food (aqueous solution of honey), may guarantee the survival and complete development of the immature and adult stages of C. maculata in the laboratory. The immature stages developed only when Apiaceous flowers were offered with E. kuehniella eggs. The food with only one of the alternative prey (moth eggs or fly larvae) or moth eggs + honey solution resulted in fertile adults; however, the number of eggs/cluster was greater for the foods with E. kuehniella eggs + honey solution, A. graveolens flowers, or only D. melanogaster. Foods comprising only the two Apiaceous species, only the honey solution, or only water resulted in larval development up to a specific instar. Adults of C. maculata also survived on these foods, but there was no oviposition. The foods of the two Apiaceous species produced heavier adults only when associated with E. kuehniella eggs. The results indicate that the zoophytophagous habit of C. maculata should be considered in conservation biocontrol programs aimed at using this lady beetle to control crop pests. 相似文献
48.
Maria Teresa Scicluna Andrea CaprioliGiorgio Saralli Giuseppe MannaAntonino Barone Antonella CersiniGiusy Cardeti Renato Ugo CondoleoGian Luca Autorino 《Veterinary microbiology》2010
Only limited information is available on the epidemiology and pathogenesis of Bovine Herpesvirus 1 (BoHV-1) in domestic buffalos. In this study, a virulent BoHV-1 field strain isolated from cattle was inoculated into buffaloes to evaluate their susceptibility to the virus and to investigate the establishment of viral latency through clinical, virological and serological investigations. Latency was also studied by attempting viral reactivation using pharmacological induction. Six of seven male, 5 months old buffaloes were intranasally inoculated with BoHV-1; the other animal was kept as negative control. The animals were clinically monitored during the post-infection (P.I.) and the post-pharmacological induction (P.P.) periods. During these periods, nasal and rectal swabs, and blood samples, with and without anticoagulant, were collected at 2–3 day intervals. On culling the animals, 206 days P.I., their trigeminal ganglia and tonsils were collected. No clinical signs referable to BoHV-1 were observed throughout the experimental period. However, seropositivity was detected in all infected animals within day 20 P.I., using BoHV-1 glycoprotein E and glycoprotein B competitive ELISAs (IDEXX) and virus neutralisation test. In real-time PCR (RT-PCR), five of these animals were positive, at least once, for nasal or rectal swabs, during the P.I. period. The sixth infected animal was found positive only in the trigeminal ganglia after culling. Ganglia were also positive for two other animals. Virus isolation in permissive cell-lines was successful for a part of the RT-PCR positive samples. The detected viruses were confirmed by genetic analysis as identical to the inoculated strain. No evidence of infection was observed in the negative control. This study represents the first experimental transmission of BoHV-1 in buffaloes, confirming their susceptibility to infection and their possible role as host/reservoirs of BoHV-1. 相似文献
49.
Renato G Credie Francisco J Teixeira Neto Tatiana H Ferreira Antônio JA Aguiar Fabio C Restitutti José E Corrente 《Veterinary anaesthesia and analgesia》2010,37(3):240-249
ObjectiveTo investigate the effects of methadone on the minimum alveolar concentration of isoflurane (ISOMAC) in dogs.Study designProspective, randomized cross-over experimental study.AnimalsSix adult mongrel dogs, four males and two females, weighing 22.8 ± 6.6 kg.MethodsAnimals were anesthetized with isoflurane and mechanically ventilated on three separate days, at least 1 week apart. Core temperature was maintained between 37.5 and 38.5 °C during ISOMAC determinations. On each study day, ISOMAC was determined using electrical stimulation of the antebrachium (50 V, 50 Hz, 10 mseconds) at 2.5 and 5 hours after intravenous injection of physiological saline (control) or one of two doses of methadone (0.5 or 1.0 mg kg?1).ResultsMean (±SD) ISOMAC in the control treatment was 1.19 ± 0.15% and 1.18 ± 0.15% at 2.5 and 5 hours, respectively. The 1.0 mg kg?1 dose of methadone reduced ISOMAC by 48% (2.5 hours) and by 30% (5 hours), whereas the 0.5 mg kg?1 dose caused smaller reductions in ISOMAC (35% and 15% reductions at 2.5 and 5 hours, respectively). Both doses of methadone decreased heart rate (HR), but the 1.0 mg kg?1 dose was associated with greater negative chronotropic actions (HR 37% lower than control) and mild metabolic acidosis at 2.5 hours. Mean arterial pressure increased in the MET1.0 treatment (13% higher than control) at 2.5 hours.Conclusions and clinical relevanceMethadone reduces ISOMAC in a dose-related fashion and this effect is lessened over time. Although the isoflurane sparing effect of the 0.5 mg kg?1 dose of methadone was smaller in comparison to the 1.0 mg kg?1 dose, the lower dose is recommended for clinical use because it results in less evidence of cardiovascular impairment. 相似文献
50.