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101.
Impact of foliar nickel application on urease activity,antioxidant metabolism and control of powdery mildew (Microsphaera diffusa) in soybean plants 下载免费PDF全文
J. P. Q. Barcelos H. P. G. Reis C. V. Godoy P. L. Gratão E. Furlani Junior F. F. Putti M. Campos A. R. Reis 《Plant pathology》2018,67(7):1502-1513
Nickel (Ni) is a cofactor for urease, an enzyme that breaks down urea into ammonia and carbon dioxide. This study aimed to evaluate the physiological impact of Ni on urea, antioxidant metabolism and powdery mildew severity in soybean plants. Seven levels of Ni (0, 10, 20, 40, 60, 80 and 100 g ha?1) alone or combined with the fungicides fluxapyroxad and pyraclostrobin were applied to soybean plants. The total Ni concentration ranged from 3.8 to 38.0 mg kg?1 in leaves and 3.0 to 18.0 mg kg?1 in seeds. A strong correlation was observed between Ni concentration in the leaves and seeds, indicating translocation of Ni from leaves to seeds. Application of Ni above 60 g ha?1 increased lipid peroxidation in the leaf tissues, indicative of oxidative stress. Application of 40 g ha?1 Ni combined with 300 mL ha?1 of fungicide reduced powdery mildew severity by up to 99%. Superoxide dismutase, catalase, peroxidase and urease enzyme activity were greatest under these conditions. Urea concentration decreased in response to Ni application. Urease activity in soybean leaves showed a negative correlation with powdery mildew severity. The leaf Ni concentration showed a positive correlation with the urease and a negative correlation with powdery mildew severity. The results of this study suggest that urease is a key enzyme regulated by Ni and has a role in host defence against powdery mildew by stimulating antioxidant metabolism in soybean plants. 相似文献
102.
Effects of harvesting perennial ryegrass at different levels of herbage mass on voluntary intake and in vivo digestibility in sheep 下载免费PDF全文
M. Beecher R. Baumont M. O'Donovan T. M. Boland J. Aufrère C. Fleming N. Galvin E. Lewis 《Grass and Forage Science》2018,73(2):553-561
The production performance of herbage‐fed animals is affected by herbage voluntary dry‐matter intake (VDMI) and organic matter digestibility. The objective of this study was to determine the effect of herbage mass (HM) on in vivo herbage voluntary intake and digestibility in sheep. The three HM treatments were as follows: 1,100 kg dry matter (DM)/ha (low, L), 2,300 kg DM/ha (medium, M) and 3,700 kg DM/ha (high, H). The study was a Latin square design, repeated on two occasions in 2012: 24 May to 20 July (summer) and 21 July to 5 October (autumn). Twelve Texel wether sheep (individually housed) were offered fresh cut perennial ryegrass herbage for ad libitum consumption. Using the total faecal collection method, the digestibility of dry matter, organic matter, neutral detergent fibre and acid detergent fibre was determined. In summer, L had a similar VDMI to M and both had a higher VDMI than H. In autumn, L had a higher VDMI than both M and H. For dry‐matter digestibility and organic matter digestibility, there was no significant difference between L and M, which were both higher than H. For every 1% increase in neutral detergent fibre digestibility, VDMI increased by 0.03 kg. In the zero‐grazing scenario examined, offering low (1,100 kg DM/ha) HM swards enabled animals to achieve high intakes of highly digestible herbage, which should ensure high animal production performance. 相似文献
103.
Andr M. Almeida Alexandre Campos Sofia van Harten Luís Alfaro Cardoso Ana Varela Coelho 《Research in veterinary science》2009,87(2):196-199
In several laboratory and production species, the establishment of a proteome reference map of a specific tissue has been accomplished. The rabbit is widely used as both a production and experimental animal. A lot of physiology research involving the gastrocnemius muscle of rabbit is described, although no reference proteome map is available. In this work, the first reference map of the rabbit’s gastrocnemius muscle using 2D gel electrophoresis and the identification of proteins through peptide mass fingerprinting (PMF) was established. A total of 45 proteins were localized and identified with three major roles: cell structure and contractile apparatus; metabolic and cell defense proteins. A reference map of major proteins expressed is described enabling possible comparisons with other physiological studies. 相似文献
104.
Bianca Chiganer Cramer Balassiano Mnica Rodrigues Campos Rita de Cssia Alves Alcantara de Menezes Maria Julia Salim Pereira 《Preventive veterinary medicine》2009,91(2-4):234-240
Factors associated with parasitism by helminths and protozoans in 500 dogs presented to three veterinary clinics in the municipality of Rio de Janeiro from November 2003 to September 2004 were evaluated. Dogs were submitted to physical examination and owners were interviewed about the animal's management. One fecal sample from each dog was examined by centrifugal flotation and sedimentation methods followed by the safranin–methylene blue staining technique. Positive results for gastrointestinal parasites were detected in 46.4% of the examined samples. Infection with protozoans (29.6%) was more frequent than with helminths (23.2%). Cryptosporidium sp. (26.2%) and Ancylostoma sp. (15.2%) were the most frequent parasites. Logistic regression analysis showed that age (p < 0.001), access to soil (p < 0.001), hygiene of the environment (p = 0.001), illness (p = 0.007), owner's level of education (p < 0.006) and veterinary clinic (p = 0.043) were associated with gastrointestinal parasite infections in dogs. Treatment and control are especially important for puppies. Adult dogs should be submitted to fecal examination before treatment, placing special emphasis on those that present one or more factors associated with infection. 相似文献
105.
Net requirements of calcium, magnesium, sodium, phosphorus, and potassium for growth of Nellore × Red Angus bulls, steers, and heifers 总被引:1,自引:0,他引:1
Mario Luiz Chizzotti Sebastio de Campos Valadares Filho Luis Orlindo Tedeschi Pedro Veiga Rodrigues Paulino Mrio Fonseca Paulino Rilene Ferreira Diniz Valadares Paloma Amaral Pedro Del Bianco Benedeti Tainnah Ikegami Rodrigues Mozart Alves Fonseca 《Livestock Science》2009,124(1-3):242-247
A comparative slaughter trial was conducted to assess the net requirements for gain of Ca, P, Na, K and Mg of bulls, steers and heifers of Nellore and Red Angus crossbreds. Twenty seven F1 Nellore and Red Angus crossbred calves (9 steers, 9 bulls, and 9 heifers), averaging 274 kg BW, were used. At the beginning of the trial, three animals from each gender were slaughtered to determine the initial body composition. The remaining 18 animals (3 animals of each gender) were randomly assigned to two treatments: fed 0.75 or 1.5% of BW of concentrate. The diets were based on corn silage and were isonitrogenous (2% N, DM). After three growing periods of 28 d, all animals were slaughtered. The cleaned gastrointestinal tract, organs, carcass, head, hide, tail, feet, and tissues were weighed to determine the empty BW (EBW). These parts were ground separately and subsampled for chemical analyses. The log of the contents of each mineral in the empty body was regressed on the log of the EBW to estimate the net requirement for each mineral per kg of empty body gain (EBG). There were no differences (P > 0.05) in the net requirements for growth of all macrominerals among genders. The equations of the pooled data of the net requirements for growth (g/kg EBG) were: 332.6 × EBW − 0.6367 for Ca, 112.1 × EBW − 0.5615 for P, 10.85 × EBW − 0.3992 for Na, 4.01 × EBW − 0.153 for K, and 3.589 × EBW − 0.462 for Mg. Our findings indicated that retained Ca and retained P were poorly related to the retained protein. 相似文献
106.
Catarina Campos M. Filipa Castanheira Sofia Engrola Luísa M. P. Valente Jorge M. O. Fernandes Luís E. C. Conceição 《Fish physiology and biochemistry》2013,39(6):1485-1496
The present work examined the short- and long-term effects of three rearing temperatures on protein metabolism and growth trajectories of Senegalese sole larvae using 14C-labelled Artemia protein as feed. A first feeding trial was performed on larvae reared at 15, 18 and 21 °C (at 26, 17 and 14 days post-hatching (dph), respectively) and a second trial conducted on post-larvae after transfer to the same rearing temperature (~20 °C) (49, 35 and 27 dph, in larvae initially reared at 15, 18 and 21 °C, respectively). Temperature greatly influenced larvae relative growth rate (RGR) and survival, since growth at 15 °C was severely depressed. Protein digestibility and retention was highest at 18 °C during the first trial (85.35 ± 1.16 and 86.34 ± 2.33 %, respectively). However, during the second trial, post-larvae from 15 °C had the highest feed intake and protein digestibility (3.58 ± 1.54 and 75.50 ± 1.35 %, respectively), although retention was similar between treatments. Furthermore, after transfer to 20 °C larvae from 15 °C experienced compensatory growth, which was observed until 121 dph, and confirmed by RGR values, which were significantly higher at 15 ºC than at 21 ºC or 18 ºC. Results from the present study show that Solea senegalensis larval development, survival and protein digestion and retention are highly affected by thermal history. 相似文献
107.
Genetic parameters for spawning and growth traits in the Pacific white shrimp (Penaeus (Litopenaeus) vannamei) 下载免费PDF全文
Alejandra Caballero‐Zamora Eugenia Guadalupe Cienfuegos‐Rivas Hugo H Montaldo Gabriel Ricardo Campos‐Montes Alfonso Martínez‐Ortega Héctor Castillo‐Juárez 《Aquaculture Research》2015,46(4):833-839
The aim of this study was to estimate genetic parameters for spawning traits and growth traits in a breeding line of Pacific white shrimp, Penaeus (Litopenaeus) vannamei, selected for growth and survival. Traits studied were number of eggs (NE) and number of nauplii (NN) and female body weight at insemination (FWI) and body weight at 130 days of age (BW130). Genetic parameters were estimated using a multivariate animal model. Heritability for NE and NN were estimated as 0.13 ± 0.04 and 0.03 ± 0.04 respectively. The contribution to NN total variation due to ‘factors associated with male’ effect was estimated as 0.47 ± 0.07. In the cases of FWI and BW130, heritability was estimated as 0.44 ± 0.08 and 0.19 ± 0.03 respectively. Genetic correlation between FWI and NE was estimated as 0.49 ± 0.15, between FWI and NN as 0.54 ± 0.39 and between NE and NN as 0.27 ± 0.41, whereas the genetic correlations of FWI, NE and NN with BW130 were 0.30 ± 0.13, ?0.21 ± 0.19 and ?0.25 ± 0.38 respectively. Although it is important to perform more studies on this issue, our results found no evidence of a genetic antagonistic effect between female reproductive traits and body weight at harvesting (130 days of age) in P. vannamei. 相似文献
108.
Maurine Sepúlveda-Caamaño Marisol Vargas Ernesto Moya-Elizondo Pía Oyarzúa Jorge Campos 《Archives of Agronomy and Soil Science》2018,64(2):244-256
Lentil is cultivated in Chilean Mediterranean drylands, in areas with soils that are nutrient depleted and eroded. Inoculation of lentil with rhizobia in co-inoculation with growth promoting rhizobacteria would allow higher biomass and an opportunity for early nodulation and increased nitrogen fixation. The objective of this research was to select rhizosferic bacteria (PGPR) from lentils and to evaluate their effect on lentil nodulation in co-inoculation with rhizobia. Sixty three lentil rhizobacteria isolates where obtained from nine soils in the mediterranean area. These were fingerprinted through BOX-PCR reducing the number to 57 distinct strains. The strains were evaluated for ACCdeaminase activity, IAA production and compatibility with rhizobia. Seventeen strains showed ACC-deaminase activity, all of them synthesized IAA and 38 were compatible with the rhizobia. Ten selected strains were identified as Pseudomonas spp. through 16S rRNA sequencing. The strains were inoculated in lentil seedlings growing on seed germination pouches, to evaluate nodule formation. The strain LY50a increased early nodulation in 85% in comparison to the control inoculated with rhizobia (AG-84) only. In conclusion, bacteria from the rhizosphere from Mediterranean soils of Chile can be used as nodulation promoters in lentils. 相似文献
109.
110.
M. Campos K. Peremans L. Duchateau A. Dobbeleir E. Vandermeulen I. van Hoek G. Paes S. Daminet 《Domestic animal endocrinology》2010
In human medicine, recombinant human thyroid-stimulating hormone (rhTSH) increases thyroid radioactive iodine uptake (RAIU), allowing radioiodine-131 (131I) dose reduction and greater efficacy in the treatment of differentiated thyroid cancer and multinodular goiter. The goal of this study was to evaluate the effect of rhTSH, administered 24 h and 48 h before radioiodine-123 (123I), on the thyroid RAIU in healthy dogs. Seven healthy euthyroid beagles were randomly allocated to 3 groups (2 groups of 2 dogs and 1 group of 3 dogs) in a prospective, blinded, crossover study. At Week 1, 1 group received 123I for a baseline RAIU; 1 group received 100 μg of rhTSH IV 24 h before 123I, and 1 group received 100 μg of rhTSH IV 48 h before 123I. All dogs received 37 MBq of radioactive 123I IV, and thyroid RAIU was determined 8 h, 24 h, and 48 h thereafter. The study was designed in such a manner that each dog received the 3 treatments and a wash-out period of 3 wk was respected in between. Blood samples were taken for measurement of serum total thyroxine (TT4) and thyrotropin (TSH) concentrations at baseline and 6 h, 12 h, 24 h, and 48 h after rhTSH administration. Recombinant human TSH caused no significant change on thyroid RAIU. The overall mean thyroid RAIU significantly decreased during the study independent of the treatment. Recombinant human TSH significantly increased serum TT4 concentration, which peaked 6 h after rhTSH administration. Compared to baseline, serum TSH concentration remained higher at 6 h, 12 h, 24 h, and 48 h. However, a statistically significant difference was reached only at 6 h and 12 h after rhTSH administration. No adverse effects of rhTSH were observed during the study. Further studies are needed to determine the best timing and dosage of administration of rhTSH in healthy and thyroid carcinoma dogs. 相似文献