Mitigation of N₂O emissions from grassland by nitrification inhibitor and Actilith F2 applied with fertilizer and cattle slurry     

P. Merino  J.M. Estavillo  L.A. Graciolli  M. Pinto  M. Lacuesta  A. Muñoz-Rueda  C. Gonzalez-Murua 《Soil Use and Management》2002,18(2):135-141

Abstract. Nitrous oxide (N₂O) is involved in both ozone destruction and global warming. In agricultural soils it is produced by nitrification and denitrification mainly after fertilization. Nitrification inhibitors have been proposed as one of the management tools for the reduction of the potential hazards of fertilizer-derived N₂O. Addition of nitrification inhibitors to fertilizers maintains soil N in ammonium form, thereby gaseous N losses by nitrification and denitrification are less likely to occur and there is increased N utilization by the sward. We present a study aimed to evaluate the effectiveness of the nitrification inhibitor dicyandiamide (DCD) and of the slurry additive Actilith F2 on N₂O emissions following application of calcium ammonium nitrate or cattle slurry to a mixed clover/ryegrass sward in the Basque Country. The results indicate that large differences in N₂O emission occur depending on fertilizer type and the presence or absence of a nitrification inhibitor. There is considerable scope for immediate reduction of emissions by applying DCD with calcium ammonium nitrate or cattle slurry. DCD, applied at 25 kg ha^–1, reduced the amount of N lost as N₂O by 60% and 42% when applied with cattle slurry and calcium ammonium nitrate, respectively. Actilith F2 did not reduce N₂O emissions and it produced a long lasting mineralization of previously immobilized added N.  相似文献   

Stem cell factor supports migration in canine mesenchymal stem cells     

Nathaly Enciso  Luciana L. K. Ostronoff  Guillermo Mejías  Leticia G. León  María Luisa Fermín  Elena Merino  Cristina Fragio  Luis Avedillo  Concepción Tejero 《Veterinary research communications》2018,42(1):29-38

Adult Mesenchymal Stem Cells (MSC) are cells that can be defined as multipotent cells able to differentiate into diverse lineages, under appropriate conditions. These cells have been widely used in regenerative medicine, both in preclinical and clinical settings. Initially discovered in bone marrow, MSC can now be isolated from a wide spectrum of adult and foetal tissues. Studies to evaluate the therapeutic potential of these cells are based on their ability to arrive to damaged tissues. In this paper we have done a comparative study analyzing proliferation, surface markers and OCT4, SOX9, RUNX2, PPARG genes expression in MSC cells from Bone marrow (BMMSC) and Adipose tissue (ASC). We also analyzed the role of Stem Cell Factor (SCF) on MSC proliferation and on ASCs metalloproteinases MMP-2, MMP-9 secretion. Healthy dogs were used as BMMSC donors, and ASC were collected from omentum during elective ovariohysterectomy surgery. Both cell types were cultured in IMDM medium with or without SCF, 10% Dog Serum (DS), and incubated at 38 °C with 5% CO2. Growth of BMMSCs and ASCs was exponential until 25–30 days. Flow citometry of MSCs revealed positive results for CD90 and negative for CD34, CD45 and MCH-II. Genes were evaluated by RT-PCR and metalloproteinases by zymografy. Our findings indicate morphological and immunological similarities as well as expression of genes from both origins on analyzed cells. Furthermore, SCF did not affect proliferation of MSCs, however it up-regulated MMP-2 and MMP-9 secretion in ASCs. These results suggest that metalloproteinases are possibly essential molecules pivoting migration.  相似文献   

Fusarium confers protection against several mycelial pathogens of pepper plants     

J. Díaz†  C. Silvar  M. M. Varela‡  A. Bernal  F. Merino 《Plant pathology》2005,54(6):773-780

Inoculation of nonhost pepper ( Capsicum annuum ) plants with the tomato wilt pathogen, Fusarium oxysporum f.sp. lycopersici (FOL), caused no symptoms and the fungus was not recovered from any part of the plant. FOL, however, partially protected pepper plants from subsequent infection with Phytophthora capsici , Verticillium dahliae or Botrytis cinerea by significantly reducing the percentage of diseased plants and the appearance and intensity of symptoms. FOL did not inhibit the mycelial growth of these pathogens in vitro . The protection induced by FOL against Botrytis was inhibited by 1-methylcyclopropene (MCP), an inhibitor of ethylene perception, suggesting the involvement of this hormone in the signalling of FOL-induced resistance. The activities of β-1,3-glucanase and peroxidase 48 h after FOL induction were similar to those in control plants. Chitinase activity, however, was higher in the stems of plants inoculated with FOL. A study of the levels of phenolic compounds revealed that cell-wall-bound phenolics were more abundant in plants treated with FOL, especially in stems, while soluble phenolic contents did not differ.  相似文献   

Evaluation of the local analgesic effect of ketamine in the palmar digital nerve block at the base of the proximal sesamoid (abaxial sesamoid block) in horses     

López-Sanromán FJ  Cruz JM  Santos M  Mazzini RA  Tabanera A  Tendillo FJ 《American journal of veterinary research》2003,64(4):475-478

OBJECTIVE: To evaluate the local analgesic effect of ketamine in a palmar digital nerve block at the base of the proximal sesamoid (abaxial sesamoid block) in horses. ANIMALS: 36 mature healthy Andalusian horses. PROCEDURE: Horses were randomly assigned to 4 groups of 9 horses each and received an abaxial sesamoid block in a randomly chosen forelimb with 1 of the following: saline (0.9% NaCl) solution, 1% ketamine solution, 2% ketamine solution, or 3% ketamine solution. To determine analgesia, the radiant heat lamp-hoof withdrawal model was used as a noxious thermal stimulus. Before each nerve block, baseline hoof withdrawal reflex latency (HWRL, time between lamp illumination and withdrawal of the hoof) was determined; after the nerve block, local analgesic effects were determined by measuring HWRL at 2 and 5 minutes after injection and then every 5 minutes for a total period of 1 hour. RESULTS: Significant differences in HWRL were found between baseline values and values at 2 to 15 minutes following a nerve block with ketamine. Significant differences were found between HWRL values at every time point from 2 to 10 minutes following a nerve block with saline solution, compared with 1 or 2% ketamine solution. Similarly, significant differences were found between HWRL values at every time point from 2 to 15 minutes following a nerve block with saline solution, compared with 3% ketamine solution. CONCLUSIONS AND CLINICAL RELEVANCE: Abaxial sesamoid block with ketamine ensures adequate analgesia in horses with an onset of action of 2 minutes and a maximal duration of action of 15 minutes.  相似文献   

Assessment of real-time PCR as a method for determining the presence of <Emphasis Type="Italic">Verticillium dahliae</Emphasis> in different Solanaceae cultivars     

Carmen Gayoso  Oscar Martínez de Ilárduya  Federico Pomar  Fuencisla Merino de Cáceres 《European journal of plant pathology / European Foundation for Plant Pathology》2007,118(3):199-209

Real-time PCR was used to detect and quantify Verticillium dahliae and to assess the susceptibility of four Capsicum annuum cultivars (Luesia, Padrón, SCM331 and PI201234) and the Capsicum chinense cv. C118 to this pathogen. The symptoms which developed after infection included stunting and yellowing, and were more acute in the cv. SCM331, which also suffered defoliation in later stages of the disease and in C118, which suffered severe stunting. Quantification of the pathogen DNA in roots 23 and 34 days post-inoculation (dpi) revealed that there were significantly higher amounts of Verticillium dahliae DNA in C118 than in the other cultivars, followed by SCM331, Padrón and PI201234. The lowest amounts of fungal DNA in roots were found in Luesia. In hypocotyls, the highest amounts of fungal DNA were found in SCM331, while Luesia, Padrón and PI201234 had much lower amounts, and C118 had intermediate levels. When a compatible versus an incompatible system was studied, using the near-isogenic tomato lines LA3030 (susceptible) and LA3038 (resistant to V. dahliae), we were able to detect fungal DNA in both lines. As expected, the fungus/plant DNA ratio was lower in LA3038 than in LA3030 and it decreased with time in LA3038. The amount of Verticillium dahliae DNA in the roots of LA3030 remained constant between days 23 and 34 post-inoculation, but increased 10-fold in collars. Finally, when real-time PCR was applied as a diagnostic method to samples from pepper plants, soil and water collected from farms in northwest Spain, we were able to detect V. dahliae DNA in these samples even when symptoms of the disease were not evident.  相似文献   

Sulphur accumulation after Verticillium dahliae infection of two pepper cultivars differing in degree of resistance     

M. Novo  C. M. Gayoso  F. Pomar  M. M. Lucas  A. Ros Barceló  F. Merino 《Plant pathology》2007,56(6):998-1004

Elemental sulphur levels, sulphur localization in stems, and levels of sulphate, glutathione and cysteine were studied in pepper ( Capsicum annuum ) cvs Yolo Wonder (higher resistance) and Luesia (lower resistance) after inoculation with Verticillium dahliae , the cause of vascular wilt. Accumulation of elemental sulphur (S⁰) was first detected 10 days after inoculation in Yolo Wonder (mean S⁰ level 7·3  µ g g⁻¹ DW), and 15 days after inoculation in Luesia (mean S⁰ level 3·3  µ g g⁻¹ DW). The maximum level was reached 21 days after inoculation in Yolo Wonder (14·1  µ g g⁻¹ DW). In control plants, elemental sulphur was not detected. SEM-EDX (scanning electron microscopy-energy dispersive X-ray microanalysis) indicated that the sulphur was not restricted to a specific location, but was dispersed throughout the vascular tissue. Sulphate levels showed a decline at the end of the experiment in inoculated plants, possibly related to the increase in sulphur levels seen in the two cultivars. The differences in sulphate levels between the two cultivars may be due to faster sulphate breakdown in cv. Yolo Wonder.  相似文献   

Time lag between peak concentrations of plasma and salivary cortisol following a stressful procedure in dairy cattle     

Carlos E Hernandez  Tomas Thierfelder  Kerstin Svennersten-Sjaunja  Charlotte Berg  Agustin Orihuela  Lena Lidfors 《Acta veterinaria Scandinavica》2014,56(1)

Background

Measurement of salivary cortisol has been used extensively as a non-invasive alternative to blood sampling to assess adrenal activity in ruminants. However, there is evidence suggesting a considerable delay in the transfer of cortisol from plasma into saliva. Previous studies in cattle have used long sampling intervals making it difficult to characterise the relationship between plasma and salivary cortisol (PLCort and SACort, respectively) concentrations at different time points and determine whether or not such a time lag exist in large ruminants. Therefore, the objective of this study was to characterise the relationship between plasma and salivary cortisol and determine if there is a significant time lag between reaching peak cortisol concentrations in plasma and saliva across a 4.25 h time-period, using short sampling intervals of 10–15 min, following social separation in dairy cattle.Five cows were separated from their calves at 4 days after calving, and six calves were separated from a group of four peers at 8 weeks of age. Following separation, the animals were moved to an unfamiliar surrounding where they could not see their calves or pen mates. The animals were catheterised with indwelling jugular catheters 1 day before sampling. Blood and saliva samples were obtained simultaneously before and after separation.

Results

In response to the stressors, PLCort and SACort increased reaching peak concentrations 10 and 20 min after separation, respectively. This suggested a 10 min time lag between peak cortisol concentrations in plasma and saliva, which was further confirmed with a time-series analysis. Considering the 10 min time lag, SACort was strongly correlated with PLCort (P < 0.0001).

Conclusions

Salivary cortisol correlates well with plasma cortisol and is a good indicator of the time-dependent variations in cortisol concentrations in plasma following acute stress. However, there is a time lag to reach peak cortisol concentrations in saliva compared to those in plasma, which should be considered when saliva samples are used as the only measure of hypothalamic-pituitary-adrenal axis response to stress in cattle.  相似文献   

Genetic improvement of farmed tilapias: Biochemical characterization of strain differences in Nile tilapia     

Julie M. Macaranas  Liza Q. Agustin  Ma. Carmen A. Ablan  Ma. Josefa R. Pante  Ambekar A. Eknath  Roger S. V. Pullin 《Aquaculture International》1995,3(1):43-54

Four African wild strains (Egypt, Ghana, Senegal and Kenya) and four established Asian farmed strains of Nile tilapia, Oreochromis niloticus (popularly known in the Philippines as Taiwan, Thailand, Singapore and Israel) were analysed electrophoretically at 30 protein loci to estimate genetic differences among the strains. All strains shared alleles at 14 monomorphic and 16 variable loci. Among the African strains, characteristic allele frequency differences were observed at AAT-1 ^* 46 for Ghana and Senegal, ADH ^* 83 for Kenya, ADH ^* 120 for Senegal, G3PDH-2 ^* 300 for Egypt, IDDH ^* 67 for Senegal, sMDH-1 ^* 120 for Kenya and SOD ^* 150 for Senegal. Genetic distance values among the strains revealed a clustering of the farmed strains with Egypt and Ghana O. niloticus, a slight separation of the Senegal strain and a larger separation of the Kenya strain. This profile may reflect the origins of the few founder populations of this species previously introduced to Asia. It also confirms the wider genetic divergence of the Kenya strain (O. niloticus vulcani) from the others studied here, which are all O. n. niloticus. Observed heterozygosities of the strains ranged from 0.026 to 0.071, with the African wild strains the lower values (mean Ho = 0.036) and the farmed strains the higher ones (mean Ho = 0.056). The implications of these results to the ongoing tilapia genetic improvement programme in the Philippines are discussed.  相似文献   

Convergence of developmental mutants into a single tomato model system: 'Micro-Tom' as an effective toolkit for plant development research     

Carvalho RF  Campos ML  Pino LE  Crestana SL  Zsögön A  Lima JE  Benedito VA  Peres LE 《Plant methods》2011,7(1):18-14

Background

The tomato (Solanum lycopersicum L.) plant is both an economically important food crop and an ideal dicot model to investigate various physiological phenomena not possible in Arabidopsis thaliana. Due to the great diversity of tomato cultivars used by the research community, it is often difficult to reliably compare phenotypes. The lack of tomato developmental mutants in a single genetic background prevents the stacking of mutations to facilitate analysis of double and multiple mutants, often required for elucidating developmental pathways.

Results

We took advantage of the small size and rapid life cycle of the tomato cultivar Micro-Tom (MT) to create near-isogenic lines (NILs) by introgressing a suite of hormonal and photomorphogenetic mutations (altered sensitivity or endogenous levels of auxin, ethylene, abscisic acid, gibberellin, brassinosteroid, and light response) into this genetic background. To demonstrate the usefulness of this collection, we compared developmental traits between the produced NILs. All expected mutant phenotypes were expressed in the NILs. We also created NILs harboring the wild type alleles for dwarf, self-pruning and uniform fruit, which are mutations characteristic of MT. This amplified both the applications of the mutant collection presented here and of MT as a genetic model system.

Conclusions

The community resource presented here is a useful toolkit for plant research, particularly for future studies in plant development, which will require the simultaneous observation of the effect of various hormones, signaling pathways and crosstalk.  相似文献   

Ratio of maltose to maltulose and furosine as quality parameters for infant formula     

Morales V  Olano A  Corzo N 《Journal of agricultural and food chemistry》2004,52(22):6732-6736

Nonenzymic browning reactions in commercial infant formulas were evaluated through their furosine content as well as the isomeric disaccharides formed during processing. Lactulose was observed only in samples containing appreciable amounts of lactose, whereas maltulose was present in all samples due to the isomerization of maltose. Because formation of maltulose depends on the initial amount of maltose present, the ratio maltose/maltulose was used for comparative purposes. The ratio maltose/maltulose varied within a wide range, 27-167; therefore, low values in maltose/maltulose ratio may indicate severe processing conditions during manufacture, whereas high values may indicate mild processing conditions. Variable amounts of furosine content in samples with similar maltose/maltulose ratios may be attributed to different conditions used during storage. Levels of furosine higher than those reported for milk powder were detected in most studied samples. Determination of both furosine and maltose/maltulose ratio would yield information retrospectively about the heat treatment applied during processing and the storage conditions of commercial infant formula.  相似文献