Effects of aluminum on nutrient solution pH and nitrate/ammonium uptake by triticale     

A. M. G. Antunes  M. Antonieta Nunes 《Journal of plant nutrition》2013,36(10):1391-1401

Aluminum (Al) plant tolerance has been frequently associated with a pH increase in the rhizosphere. The changes in pH are dependent on plant genotypes and ionic composition and strength of nutrient solutions. This work was performed in order to study in triticale (Triticosecale Wittm.) the association of pH change with nitrogen (N) uptake and growth performance in acid conditions. Three‐day‐old seedlings were treated with Al (185 μM) in solutions having different proportion nitrate/ammonium (NO₃/NH₄), 15/1 and 8/1, but the same total N content. Along the period with Al treatment, several measurements have been made: pH, every day; NO₃ and NH₄ uptake from the solution as well as shoot and root biomass production every two days (five and seven days of plant age). The maximum growth inhibition (30%) of fresh weight was found in roots of plants in the 15/1 (NO/NH,) nutrient solution. The presence of a higher proportion of NH₄ (8/1 solution) had a protective effect on Al damage as shown by less growth inhibition and less reduction in NO₃ uptake. Changes in pH apparently were not relevant for the tolerance. The results suggest that NH₄ fertilization may be useful for alleviating Al toxicity in triticale.  相似文献   

Anaesthesia with ketamine/medetomidine in the rabbit: influence of route of administration and the effect of combination with butorphanol     

P Hedenqvist DVM    HE Orr† BVMS  Cert LAS    JV Roughan† BSc  PhD    LM Antunes† MSc DVM  & PA Flecknell† M.A Vet MB  PhD  DLAS  Dip ECVA  MRCVS 《Veterinary anaesthesia and analgesia》2002,29(1):14-19

Objective To compare the characteristics of anaesthesia induced with ketamine/medetomidine administered by the subcutaneous and intramuscular routes and to assess the effects of the addition of butorphanol to this combination. Study design Prospective randomised study. Animals Six female New Zealand White rabbits. Methods Rabbits were given one of four combinations of ketamine and medetomidine (K/M) either subcutaneously (SC) or intramuscularly (IM) on four successive occasions with a 7‐day interval between treatments. The dose combinations were; 15/0.25 mg kg^?1 SC; 15/0.25 mg kg^?1 IM; 15/0.5 mg kg^?1 SC, and 15/0.25 mg kg^?1 together with 0.4 mg kg^?1 butorphanol (K/M/B) SC. The effects of anaesthesia on arterial blood gas values and cardiovascular variables were recorded at predetermined time points. Toe and ear pinch reflexes were judged to determine the duration of surgical anaesthesia. Loss of the righting reflex was used to measure the duration of sleep time. Analyses used repeated measures analysis of variance. Results All groups lost the righting reflex and ear pinch response. Three animals in the groups that received K/M alone lost their toe pinch reflex, whereas four lost this reflex when given K/M/B. Time of onset of loss of the righting, toe and ear pinch reflexes did not differ significantly among the groups. The higher dose combination of medetomidine with ketamine and the combination of K/M/B produced a greater duration of loss of the ear pinch response than the lower dose of K/M administered by either route. No significant differences were found among the groups in the duration of loss of the toe pinch reflex. All animals developed a moderate bradycardia (mean heart rate <166 beats minute^?1) and moderate hypoxaemia (mean P_aO₂ < 6.0 kPa). Animals given butorphanol showed the greatest reduction in respiratory rate (31 ± 13 breaths minute^?1, p < 0.05) but this was not reflected in any significant differences in arterial PCO₂, PO₂ or pH among the groups. Conclusions Administration of K/M by the SC route produced equivalent effects in comparison to intramuscular administration. The addition of butorphanol increased the duration of anaesthesia, but produced a slight increase in the degree of respiratory depression. All dose rates resulted in hypoxaemia so oxygen should be administered when these combinations are used in rabbits. Clinical relevance Subcutaneous administration is both technically simpler and may cause less discomfort to the animal than IM injection, and so is preferred. The combination of K/M with butorphanol has relatively minor effects on the depth and duration of anaesthesia, so offers little advantage to the use of K/M alone.  相似文献   

Isolation and molecular characterisation of Neospora caninum in cattle in New Zealand     

CM Okeoma  NB Williamson  WE Pomroy  KM Stowell  LM Gillespie 《New Zealand veterinary journal》2013,61(6):364-370

AIM: To isolate Neospora caninum from the brains of naturally infected cattle and use molecular techniques to characterise the isolates.

METHODS: Neospora caninum tachyzoites were isolated in Vero cell culture from the brains of a cow and two calves. The isolates were characterised using polymerase chain reaction (PCR) methods, DNA sequencing, an immunofluorescent anti-body test (IFAT), transmission electron microscopy (TEM), and immunohistochemistry (IHC). The brains of the three cattle were subjected to histopathological examination. A pathogenicity study was conducted in 120 BALB/c mice.

RESULTS: Neospora caninum tachyzoites were isolated from all three cases and first observed in vitro between 14 and 17 days post-inoculation. Parasites were sub-cultured and maintained in Vero cell culture for more than 6 months. PCR products were generated for all three isolates, using two different primers. Sequencing of the PCR products and a subsequent BLAST search identified the isolates as N. caninum. In addition, the isolates tested positive using IFAT and IHC, and ultrastructure revealed by TEM was characteristic of N. caninum. Histopathological examination revealed lesions characteristic of N. caninum in 1/3 brains. In the pathogenicity study using BALB/c mice, the mortality rate was 3–7%.

CONCLUSION: This was the first successful isolation of N. caninum in New Zealand confirmed using molecular characterisation tests.  相似文献   

Rough virulent strain of Brucella ovis induces pro- and anti-inflammatory cytokines in reproductive tissues in experimentally infected rams     

João Marcelo Azevedo de Paula Antunes  Susan Dora Allendorf  Camila Michele Appolinário  Didier Quevedo Cagnini  Paula Ripamonte Figueiredo  José Buratini Júnior  Joaquin Vicente Baños  Katherine M. Kocan  José de la Fuente  Jane Megid 《Veterinary microbiology》2013,161(3-4):339-343

The ovine brucellosis caused by Brucella ovis has tropism for reproductive tissues but until now the mechanism of bacterial persistence is not understood. Cytokine expression profiles were studied for 8 months in rams after being experimentally infected with the rough virulent strain of B. ovis (R-B. ovis) to study the pathogenesis of B. ovis and immune mechanism possibly associated to bacteria tropism and persistence. The messenger RNA (mRNA) expression levels of interleukin-1α (IL-1α), IL-1β, IL-6, IL-10, IL-12, interferon-γ (INF-γ) and tumour necrosis factor-α (TNF-α) cytokines were quantified by real-time quantitative RT-PCR (qRT-PCR) in reproductive tissues (epididymus, testicles, ampolae, vesicular glands and bulbourethral glands), and non-reproductive (liver, spleen and kidneys) tissues at 30, 60, 120 and 240 days post infection (dpi). During the acute phase of infection at 30 dpi, the host immune response was most notable demonstrating an up-regulation of several cytokines in reproductive tissues, including the epididymus (IL-6, IL-1β and IL-1α), testicles (INF-γ and IL-12), bulbourethral glands (IL-6 and TNF-α) and ampolae (INF-γ, IL-10, IL-1β and IL-1α). During the development of infection, cytokine gene expression levels decreased, providing evidence of immunosuppression and evidence of immune evasion that favoured persistence of chronic R-B. ovis infection. During the chronic phase of R-B. ovis infection (120 and 240 dpi), cytokine production was down-regulated in the epididymus (IL-1β and IL-1α), testicles (INF-γ and IL-12), and ampolae (INF-γ, IL-10, IL-1β and IL-1α), with the exception of the bulbourethral glands (IL-6 and TNF-α) and epididymus (IL-6); in these tissues, R-B. ovis infection resulted in up-regulation of the pro-inflammatory cytokine IL-6. Herein, we report cytokine expression profiles in tissues of rams experimentally infected with the rough strain of B. ovis, which are associated with bacterial persistence and macrophage activation.  相似文献   

Lectin Histochemistry as a Tool to Identify Apoptotic Cells in the Seminiferous Epithelium of Syrian Hamster (Mesocricetus auratus) Subjected to Short Photoperiod     

V Seco‐Rovira  E Beltrán‐Frutos  C Ferrer  MM Sánchez‐Huertas  JF Madrid  FJ Saez  LM Pastor 《Reproduction in domestic animals》2013,48(6):974-983

Lectins have been widely used to study the pattern of cellular glycoconjugates in numerous species. In the process of cellular apoptosis, it has been observed that changes occur in the membrane sugar sequences of these apoptotic cells. The aim of our work was to identify which lectins, out of an extensive battery of the same (PNA, SBA, HPA, LTA, Con‐A, UEA‐I, WGA, DBA, MAA, GNA, AAA, SNA), show affinity for germinal cells in apoptosis, at what stage of cell death they do so and in which germinal cell types they can be detected. For this, we studied testis sections during testicular regression in Syrian hamster (Mesocricetus auratus) subjected to short photoperiod. Several lectins showed an affinity for the glycoconjugate residues of germ cells in apoptosis: Gal β1,3‐GalNAcα1, α‐d ‐mannose, N‐acetylgalactosamine and l ‐fucose. Furthermore, lectin specificity was observed for some specific germinal cells and in certain stages of apoptosis. It was also observed that one of these lectins (PNA) showed affinity for Sertoli cells undergoing apoptosis. Therefore, we conclude that the use of lectin histochemistry could be a very useful tool for studying apoptosis in the seminiferous epithelium because of the specificity shown towards germinal cells in pathological or experimentally induced epithelial depletion models.  相似文献   

Habitat structure,soil properties,and food availability do not predict terrestrial flatworms occurrence in Araucaria Forest sites     

Michelle Antunes  Ana Maria Leal-Zanchet  Carlos Roberto Fonseca 《Pedobiologia》2012,55(1):25-31

Flatworm community structure responds strongly to large-scale habitat alteration, with low diversity in disturbed environments. However, the ecological factors influencing small-scale distribution of flatworms are poorly understood. The aim of this study is to test if the occurrence of land planarians is influenced by microhabitat traits. The study was developed in two Araucaria Forest sites located in the São Francisco de Paula National Forest, southern Brazil. In each site, a 0.5 ha grid subdivided in 10 m² plots, was established. In 100 randomly selected plots, the occurrence and abundance of each land planarian species were recorded. For each plot, we also recorded information on six habitat structural traits, 21 soils properties, and 15 prey availability parameters. Sixty-six specimens were recorded, belonging to 21 species of land planarians. Although the two areas differed in relation to 17 ecological factors analyzed, mean flatworm density did not significantly differ between the two studied areas. The pattern of their abundance followed a Poisson distribution, suggesting that flatworms were randomly distributed throughout the study area. Simple logistic regressions and a multiple logistic regression, controlled for spatial autocorrelation, showed no evidence that the occurrence of terrestrial flatworms is controlled by habitat structure, prey availability or soil properties. In addition, a Principal Component Analysis, controlled for spatial autocorrelation, generated three main axes that represented 40.7% of the variation of the 42 ecological traits. This analysis showed very similar distribution of plots with and without flatworms along these three axes. The results suggest that land flatworms exhibit no pronounced microhabitat preferences inside undisturbed Araucaria Forest sites.  相似文献   

Intravenous Administration of Azumolene to Reverse Malignant Hyperthermia in Swine     

P. L. Do Carmo  G. Zapata‐Sudo  M. M. Trachez  F. Antunes  S. E. F. Guimarães  R. Debom  M. D. R. Rizzi  R. T. Sudo 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2010,24(5):1224-1228

Background: The efficacy of intravenous (IV) administration of azumolene (Az), an analogue 30‐fold more soluble than dantrolene, on pigs susceptible to malignant hyperthermia (MH) is incompletely understood. Objective: To evaluate efficacy of Az on MH crisis in pigs. Animals: Eight normal (MHN) and 7 susceptible to MH (MHS) pigs (Landrace × Large White × Pietran). Methods: Prospective, laboratory trial. Hypermetabolic crisis was observed in MHS pigs, but not in MHN pigs, after a combined administration of inhaled halothane (1.5%) and IV injection of succinylcholine (SCh; 2.5 mg/kg). Susceptibility was confirmed using a caffeine and halothane contracture test. Az was administered 15 minutes after administration of SCh. Results: Respiratory acidosis (pH 7.16 ± 0.02; Pco ₂, 46.2 ± 9.1 mmHg, HCO₃, 22.5 ± 2.3 mmol/L), fever (38.2 ± 1.1°C), cardiac arrhythmias, and muscle contracture were observed in MHS pigs. MHS pigs (n = 5) treated with Az (2 mg/kg IV) survived the crisis with attenuation of signs (pH 7.30 ± 0.10; Pco ₂, 36.3 ± 4.5 mmHg; HCO₃, 22.9 ± 2.3 mmol/L) and recovery of normal muscle tone and cardiac rhythm. Conclusions and Clinical Importance: Az represents a possible substitute for dantrolene to reverse MH crisis in susceptible pigs.  相似文献   

Characterization,specificity and sensibility of produced anti-<Emphasis Type="Italic">Rhamdia quelen</Emphasis> vitellogenin in Brazilian fish species     

Daniele Dietrich Moura Costa  Dandie Antunes Bozza  Luiz Eduardo Rizzo  Juan Garcia  Michele Dietrich Moura Costa  Ciro Alberto de Oliveira Ribeiro 《Fish physiology and biochemistry》2016,42(6):1721-1732

Endocrine-disrupting chemicals (EDCs) are widespread used and can interfere on hormone regulation with adverse consequences for both biota and human. Vitellogenin (vtg) is a yolk precursor protein synthesized by the liver in response to estrogen. In order to characterize the vtg of tropical fish Rhamdia quelen and establish a molecular biomarker, adult male individuals were exposed to 17-β-estradiol (E₂) for vtg induction and anti-R. quelen vtg polyclonal antibodies production. Vitellogenic female fish were used as positive control group. E₂-induced vtg was characterized as a glycolipophosphoprotein of high molecular mass with peptide mass fingerprint very similar in E₂-exposed male and vitellogenic female fish. A polyclonal serum containing anti-R. quelen vtg antibodies was produced and showed high specificity and sensibility to detect the vtg of three fish species: R. quelen, Piaractus mesopotamicus and Prochilodus lineatus. Wildlife and laboratory studies reported that EDCs released into the environment may alter the levels of plasma vtg in male fish, making this protein a valuable biomarker of xenoestrogens exposure. Then, we propose the use of anti-R. quelen vtg as a tool for biomonitoring studies and water quality assessment in Brazil and South American countries where the three fish species occur.  相似文献   

Principles for Sustainable Governance of the Oceans   总被引：1，自引：0，他引：1  

R Costanza  F Andrade  P Antunes  den Belt M  D Boersma  DF Boesch  F Catarino  S Hanna  K Limburg  B Low  M Molitor  JG Pereira  S Rayner  R Santos  J Wilson  M Young 《Science (New York, N.Y.)》1998,281(5374):198-199

Pressures being exerted on the ocean ecosystems through overfishing, pollution, and environmental and climate change are increasing. Six core principles are proposed to guide governance and use of ocean resources and to promote sustainability. Examples of governance structures that embody these principles are given.  相似文献   

Vetch toxicosis in cattle grazing Vicia villosa ssp dasycarpa and V benghalensis     

PAW HARPER  RW COOK†  PA GILL†  GC FRASER†  LM BADCOE‡  JM POWER§ 《Australian veterinary journal》1993,70(4):140-144

SUMMARY The epidemiological, clinical and pathological features of a disease syndrome in adult cattle grazing woolly-pod vetch (Vicia villosa ssp dasycarpa) or popany vetch (V benghalensis) are reported. Outbreaks of toxlcosis occurred between midwinter and midsummer in 3 dairy and 6 beef herds on the north coast of New South Wales, between 1982 and 1992. Friesian, Angus, Murray Grey, Guernsey and Hereford breeds were affected. Mean morbidity and case fatality rates in affected herds were 7% (65 of 889) and 69%, respectively. Signs of pruritic dermatitis, illthrift and death were associated with an eosinophilic granulomatous inflammation of many organs, particularly involving the renal cortex, dermis, myocardium, adrenal glands, lymph nodes and hepatic portal triads.  相似文献