Acute cattle intoxication from Nerium oleander pods     

Soto-Blanco B  Fontenele-Neto JD  Silva DM  Reis PF  Nóbrega JE 《Tropical animal health and production》2006,38(6):451-454

Seven outbreaks of acute intoxication from oleander (Nerium oleander) in cattle were reported in Northeast of Brazil. A total of 92 cattle were poisoned by oleander in 7 different herds; 57 animals died (67% of affected cattle). All cases reported here occurred during dry season. Two of the outbreaks resulted from offering oleander triturated and mixed with fodder. In the other cases, accidental ingestion of residual parts of oleander derived from pruning or cutting plants on grazing land were responsible. Clinical signs were diverse; the most common were locomotion disturbances, diarrhoea, depression and sudden death. Postmortem findings varied from no significant lesions to widespread haemorrhage. The presence of oleander leaves in the rumen was noted in all cases. The lack of information about the toxicity of oleanders was the main cause for the accident, which prompt us to stimulate wide divulgation of the common toxic plants.  相似文献   

Expression of terminal differentiation proteins defines stages of mouse mammary gland development     

Mikaelian I  Hovick M  Silva KA  Burzenski LM  Shultz LD  Ackert-Bicknell CL  Cox GA  Sundberg JP 《Veterinary pathology》2006,43(1):36-49

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Differential diagnosis of dog hookworms based on PCR-RFLP from the ITS region of their rDNA     

e Silva LM  Miranda RR  Santos HA  Rabelo EM 《Veterinary parasitology》2006,140(3-4):373-377

Species of Ancylostoma infecting dogs and sometimes humans are sympatric in many parts of the world. The establishment of a specific molecular diagnostic tool is important, not only to refine information for epidemiological studies, but also to evaluate the efficacy of vaccine programmes and assist in the development of specific drug treatments. The ITS region from 20 specimens of A. braziliense, collected from three separate geographical areas of Brazil, and from 10 specimens of A. caninum, collected from the same area in Brazil were sequenced and analyzed. Alignment of sequences showed that this gene is highly conserved. The intraspecific polymorphism for both species was less then 1%, whereas the interspecific polymorphism was 6.2, 7.3 and 9.4% between A. ceylanicum and A. braziliense; A. caninum and A. ceylanicum and A. ceylanicum and A. braziliense, respectively. Among the three species it was 12.3%. This revealed the ITS region as highly conserved and consequently a good molecular marker for diagnostic studies. In this work, four restriction enzymes were used in a PCR-RFLP using the ITS region of rDNA, to establish a differential diagnosis which discriminates between three Ancylostoma species, A. braziliense, A. caninum and A. ceylanicum. The best pattern was given by the HinfI enzyme, which produced different fragment sizes for each of the three species. Furthermore, the diagnostic tool differentiates DNA extracted directly from faeces of Ancylostoma-infected dogs.  相似文献   

Canine visceral leishmaniosis: a comparative analysis of the EIE-leishmaniose-visceral-canina-Bio-Manguinhos and the IFI-leishmaniose-visceral-canina-Bio-Manguinhos kits     

Lira RA  Cavalcanti MP  Nakazawa M  Ferreira AG  Silva ED  Abath FG  Alves LC  Souza WV  Gomes YM 《Veterinary parasitology》2006,137(1-2):11-16

This study evaluated the performance of the EIE-leishmaniose-visceral-canina-Bio-Manguinhos (EIE-LVC) kit and to compare it with that of the IFI-leishmaniose-visceral-canina-Bio-Manguinhos (IFI-LVC) kit. Four groups of dogs were studied: group 1 (G1), dogs with clinical signs indicative of CVL and testing positive for the parasite (n = 25); group 2 (G2), dogs with only a presumed diagnosis of CVL (n = 62); group 3 (G3), dogs that had never lived in an area where CVL is endemic and never received a blood transfusion (n = 16); group 4 (G4), dogs carrying other parasites: such as babesiosis (n = 4), ehrlichiosis (n = 6) and demodicosis (n = 1). G1 and G3 were used for the calculation of sensitivity and specificity, respectively. The EIE-LVC showed a sensitivity of 72% (IC 95%: 50.4-87.1%) and a specificity of 87.5% (IC 95%: 60.4-97.8%). The value of the kappa index was 0.975 (CI 95%: 0.926-1.024), which represents an excellent fit. For IFI-LVC, the sensitivity was 68.0% (CI 95%: 46.4-84.3%) and the specificity 87.5% (CI 95%: 60.4-97.8%). When the tests were conducted in parallel, sensitivity was 92.0% (CI 95%: 72.5-98.6%) and specificity 75.0% (CI 95%: 47.4-91.7%). However, when conducted consecutively, the tests showed a sensitivity of 48.0% (CI 95%: 28.3-68.2%) and a specificity of 100.0% (CI 95%: 75.9-99.4%). The analysis of clinically suspected dogs using IFI-LVC and EIE-LVC kits in parallel, revealed that 26/62 animals were positive. Cross-reaction was observed in a dog with demodicosis. These results lead to the following conclusions: (1) the performance of the EIE-LVC kit is not statistically different from the IFI-LVC and (2) the kits must be used in parallel if higher sensitivity is required, reducing the number of false-negative results.  相似文献   

Anthelmintic activity of Azadirachta indica A. Juss against sheep gastrointestinal nematodes     

Costa CT  Bevilaqua CM  Maciel MV  Camurça-Vasconcelos AL  Morais SM  Monteiro MV  Farias VM  da Silva MV  Souza MM 《Veterinary parasitology》2006,137(3-4):306-310

Gastrointestinal nematode control has been performed through use of anthelmintics. However, the development of resistant populations has required research into new alternatives. There are popular reports about anti-parasitic activity of Azadirachta indica in animals and plants. The aim of this study was to evaluate the anthelmintic activity of A. indica after feeding sheep with the dried leaves. In this experiment, 40 sheep were allotted into four treatment groups. Group I received a treatment of A. indica dry leaves mixed in a concentrate at a rate of 0.1 g/kg dose for 3 months. Group II was treated with double the dose of Group I. Group III was treated with closantel (Diantel) at the manufacturer-recommended dose once at the beginning of the study and Group IV was not treated. To compare treatment effects, the following parameters were evaluated: egg count per gram of feces (EPG), worm burden, weight gain and haematocrit. EPG and worm burden results were statistically evaluated using the Kruskal-Wallis test. Haematocrit and live weight gain were submitted to analysis of variance (ANOVA) and the means evaluated by Tukey's test with 95% probability. None of the evaluated parameters of the treatment groups were statistically different when compared to the control group, demonstrating that, with the protocol used, A. indica has no anthelmintic effect.  相似文献   

Diversity of the infracommunities of strongylid nematodes in the ventral colon of Equus caballus from Rio de Janeiro state, Brazil     

da Silva Anjos DH  de Lurdes A Rodrigues M 《Veterinary parasitology》2006,136(3-4):251-257

Nematodes from the ventral colon of 31 adult horses, 24 males and 9 females, in the metropolitan region of the state of Rio de Janeiro were analysed. There were 53,444 (86.4%) adults of the total recovered strongylid nematodes. They belonged to 21 species of Cyathostominae and seven of Strongylinae. Larval forms made up 13.6% (8407) of the total recovered, and 49% of the strongylid nematodes were observed in ventral colon. The most prevalent and abundant species were Cyathostomum tetracanthum, Cylicocyclus nassatus, Cylicostephanus minutus, Cylicostephanus longibursatus, Cylicostephanus leptostomus, Cylicostephanus calicatus and Cylicostephanus goldi, corresponding to 93.2% of the total adult population; these species were classified as central species, except C. goldi; and other species were classified as secondary (n = 8) and satellite (n = 14). The low Green's aggregation index, presented to central species, indicated high dispersion because they were found in a greater number of infracommunities and were proven by the greater prevalence. Only 12.1% of the horses were uninfected or infected by a single species; the other infections were multiple, ranging from 3 to 23 species.  相似文献   

Factors affecting somatic embryogenesis in conifers     

Jaime A.Teixeira da Silva  Ravindra B.Malabadi 《林业研究》2012,23(4):503-515

This review seeks to examine the extreme response of isolated somatic plant cells of apical meristematic tissues of mature conifer trees towards specific stress conditions in vitro resulting in somatic embryogenesis.Signal molecules regulating embryo development have been described in angiosperms,but very little is known about somatic rejuvenation in conifers.Recent studies on cloning of mature conifers provide new perspectives on signal molecules on cellular dedifferentiation into the embryogenic pathway.Our recent studies show that signal molecules such as butenolide,calcium ions,salicylic acid,antioxidants,amino acids,triacontanol and 24-epibrassinolide all play an important role in the conversion of somatic cells into an embryogenic pathway in many recalcitrant pines.This constitutes a major breakthrough in forest biotechnology with many practical applications in clonal forestry.  相似文献   

Effects of region, soil, land use, and terrain type on fuelwood properties of five tree/shrub species in the Sahelian and Sudanian ecozones of Mali     

Carmen Sotelo Montes  John C. Weber  Dimas A. Silva  Clarice Andrade  Graciela I. B. Mu?iz  Rosilei A. Garcia  Antoine Kalinganire 《Annals of Forest Science》2012,69(6):747-756

? Context

There is little information about inter- and intra-specific variation in fuelwood properties of trees/shrubs in West Africa.

? Aims

We studied variation in fuelwood properties of Balanites aegyptiaca, Combretum glutinosum, Guiera senegalensis, Piliostigma reticulatum, and Zizyphus mauritiana in the Sahelian and Sudanian ecozones of Mali.

? Methods

Trees were sampled on different soil (sandy, sandy/loam, or rocky), land use (parkland agroforest or woodland), and terrain (flat, temporarily flooded, or hill slope) types in five regions extending from the drier eastern to the more humid western parts of Mali. Basic density, volatile matter, fixed carbon, ash content, moisture content, gross calorific value, and fuel value index were measured for each tree and adjusted for tree age.

? Results

All fuelwood properties differed significantly among species, but there were significant species by region interactions. Most fuelwood properties of four species differed significantly among regions. Soil and/or land use type had significant effects on a few fuelwood properties of four species.

? Conclusion

In general, fuelwood production is recommended in all regions for G. senegalensis, in drier regions for B. aegyptiaca and C. glutinosum, in more humid regions for Z. mauritiana, and on rocky soils for all species. Fuelwood production of P. reticulatum is not recommended.  相似文献   

Modeling Mediterranean forest fuels by integrating field data and mapping tools     

Francisco Rodríguez y Silva  Juan Ramón Molina-Martínez 《European Journal of Forest Research》2012,131(3):571-582

Fire behavior modeling systems are important in predicting wildfire risk, fire growth, and fire effects. However, simulation software requires a new fuel modeling to include fuel treatments, prescribed fire and the transition to crown fire. The thirteen Rothermel models are insufficient in completely representing Mediterranean ecosystems. In this sense, the new American modeling includes five fuel types, requiring the acquisition of hybrid models made up of the mixture of grass and shrub and the grass or shrub mixed with litter from forest canopy. Respecting meteorological conditions and shrub characteristics, field studies have shown significant differences between American and Mediterranean models. As a consequence, the definition of new Mediterranean models requires the adjustment of specific parameters such as fuel load by category (live and dead) and particle size class (1-, 10- and 100-h time-lag), fuelbed depth and surface area-to-volume ratio. These new parameters were obtained in situ of sample itineraries, prescribed fires, and forest fires. The availability of this new modeling, validated on a field of regional scale, will facilitate preventive planning and management as well as an efficient application of suppression techniques, both ground and aerial operations, required in defending a territory against forest fires.  相似文献   

Catalysis and sulfa drug resistance in dihydropteroate synthase     

Yun MK  Wu Y  Li Z  Zhao Y  Waddell MB  Ferreira AM  Lee RE  Bashford D  White SW 《Science (New York, N.Y.)》2012,335(6072):1110-1114

The sulfonamide antibiotics inhibit dihydropteroate synthase (DHPS), a key enzyme in the folate pathway of bacteria and primitive eukaryotes. However, resistance mutations have severely compromised the usefulness of these drugs. We report structural, computational, and mutagenesis studies on the catalytic and resistance mechanisms of DHPS. By performing the enzyme-catalyzed reaction in crystalline DHPS, we have structurally characterized key intermediates along the reaction pathway. Results support an S(N)1 reaction mechanism via formation of a novel cationic pterin intermediate. We also show that two conserved loops generate a substructure during catalysis that creates a specific binding pocket for p-aminobenzoic acid, one of the two DHPS substrates. This substructure, together with the pterin-binding pocket, explains the roles of the conserved active-site residues and reveals how sulfonamide resistance arises.  相似文献