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41.
Risely Ferraz De Almeida Camila Haddad Silveira Raquel P. Mota Mara Moitinho Everton Martins Arruda Eduardo De Sá Mendonça Newton La Scala Beno Wendling 《Journal of Soils and Sediments》2016,16(10):2354-2364
Purpose
The mineralization/immobilization of nutrients from the crop residues is correlated with the quality of the plant material and carbon compartments in the recalcitrant and labile soil fractions. The objective of this study was to correlate the quality and quantity of crop residues incubated in the soil with carbon compartments and CO2-C emission, using multivariate analysis.Materials and methods
The experiment was conducted in factorial 4?+?2?+?5 with three replicates, referring to three types of residues (control, sugarcane, Brachiaria, and soybean), and two contributions of the crop residues in constant rate, CR (10 Mg ha?1 residue), and agronomic rate, AR (20, 8, and 5 Mg ha?1 residue, respectively, for sugarcane, soybean, and Brachiaria), evaluated five times (1, 3, 6, 12, and 48 days after incubation). At each time, we determined the CO2-C emission, nitrogen and organic carbon in the soil, and the residues. In addition, the microbial biomass and water-soluble, labile, and humic substance carbons fractionated into fulvic acids, humic acids and humin were quantified.Results and discussion
Higher CO2-C emissions occurred in the soil with added residue ranging from 0.5 to 1.1 g CO2-C m?2 h?1 in the first 6 days of incubation, and there was a positive correlation with the less labile organic soil fractions as well as residue type. In the final period, after 12 days of soil incubation, there was a higher relation of CO2-C emission with carbon humin. The sugarcane and soybean residue (20 Mg ha?1) promoted higher CO2-C emission and the reduction of carbon residue. The addition of residue contributed to an 82.32 % increase in the emission of CO2-C, being more significant in the residue with higher nitrogen availability.Conclusions
This study shows that the quality and quantity of residue added to soil affects the carbon sequestration and CO2-C emission. In the first 6 days of incubation, there was a higher CO2-C emission ratio which correlates with the less stable soil carbon compartments as well as residue. In the final period of incubation, there is no effect of quality and quantity of residue added to soil on the CO2-C emission.42.
Cibele Soares Pontes Maria de Fatima Arruda Alexandre Augusto de Lara Menezes & Patrícia Pereira de Lima 《Aquaculture Research》2006,37(10):1001-1006
Lack of information on the daily activity patterns of Litopenaeus vannamei (Boone 1931) might result in inadequate feed management strategies in shrimp farms. In order to provide information to improve feed management in shrimp farms, the daily activity of juvenile shrimp reared in glass aquaria was studied, using L. vannamei (7.57±1.01 g), equivalent to 33 shrimp m?2. Thirty‐two shrimp were observed, half in light and half in dark phase, over 280 h in 15 min h?1 windows. Feed was provided once a day, at 10% of tank biomass. Swimming, exploration of substrate, inactivity and cleaning were recorded through instantaneous focal sampling. During the dark phase, swimming was predominant and alternated with exploration. In the light phase, inactivity was predominant, and again alternated with exploration. Cleaning occurred evenly in both the light and the dark. Substrate exploration, which characterizes the search for food, occurred in both dark and light phases, with a most intense peak 7 h after light phase onset, indicating this as the optimal feed offer. 相似文献
43.
Addition of Seminal Plasma to Post‐thawing Equine Semen: What is the Effect on Sperm Cell Viability?
de Andrade AF Zaffalon FG Celeghini EC Nascimento J Tarragó OF Martins SM Alonso MA Arruda RP 《Reproduction in domestic animals》2011,46(4):682-686
Effect of seminal plasma addition after thawing on viability or cryocapacitation is not definitively established. This experiment was performed to verify the effect of adding seminal plasma, autologous or homologous (from an animal with good semen freezability). Five ejaculates from each of four stallions with proven fertility were collected and cryopreserved. The semen was subsequently thawed and divided into the following three treatment groups: no seminal plasma addition after semen thawing (NOSP); the addition of homologous seminal plasma after semen thawing (HSP) and the addition of autologous seminal plasma after semen thawing (ASP). The addition of 20% of seminal plasma led to an increase in the cell population that simultaneously show plasma and acrosomal membrane integrity (p < 0.05). The addition of seminal plasma did not alter the total motility, the amount of cells with mitochondrial membrane potential or the sperm velocities (average path velocity, straight-line velocity and curvilinear velocity). However, the beat/cross-frequency, straightness and linearity were reduced in ASP and HSP groups (p < 0.05). Unexpectedly, the addition of homologous seminal plasma reduced the proportion of cells with progressive motility (p < 0.05) and the addition of autologous seminal plasma reduced the amplitude of the lateral head displacement (p < 0.05). Based on the increase in the cell populations that had the plasma and acrosomal membrane integrity simultaneously identified in this study, we proposed that the addition of seminal plasma (autologous or homologous) into post-thawed semen before insemination could increase semen fertility. 相似文献
44.
das Araújo Francisca Chagas Bezerra Moura Elisa Ferreira de Rodrigues Simone Miranda de Carvalho Kenny Bonfim Arruda Tavares Eraldo José Madureira Moura Mônika Fecury da Silva Gilvan Ferreira 《Genetic Resources and Crop Evolution》2021,68(5):1809-1824
Genetic Resources and Crop Evolution - The biofortification of cassava (Manihot esculenta Crantz) roots is one of the actual goals of genetic breeding, with the development of roots richer in... 相似文献
45.
Raquel de Arruda Leme Juliane Ribeiro Alice Fernandes Alfieri Amauri Alcindo Alfieri 《Veterinary research communications》2013,37(2):183-186
The aims of this study were to evaluate torque teno sus virus (TTSuV) infection in healthy slaughter-age pigs and to compare the similarities of the untranslated region (UTR) nucleotide (nt) sequences obtained from different biological samples of the same animals. Fifty-eight pigs were evaluated by PCR assay for the presence of TTSuV in paired samples of liver and serum (Group 1, n?=?27) and lung and serum (Group 2, n?=?31). All the pigs were positive for TTSuV infection in the organs sampled and 94.8 % (n?=?55) presented with viraemia. The nt sequence similarities between the Groups 1 and 2 varied from 91.7 % to 96.6 % (TTSuV1) and 91 % to 95 % (TTSuV2). In Group 1, the nt sequence similarities were 93 % (TTSuV1) and 95.4 % (TTSuV2). In Group 2, the nt sequence similarities were 95 % (TTSuV1) and 91 % (TTSuV2). These results revealed the simultaneous infection with distinct strains of TTSuV1 and 2 in healthy pigs at slaughter age. 相似文献
46.
Interspecies somatic cell nuclear transfer (interspecies SCNT) has been explored in many domestic and non‐domestic animal species. However, problems arise during the development of these embryos, which may be related to species‐specific differences in nuclear–cytoplasmic communication. The objectives of this study were to investigate the possibility of producing bison embryos in vitro using interspecies SCNT and assess the developmental potential of these embryos. Treatment groups consisted of cattle in vitro fertilization (IVF) and cattle SCNT as controls and wood bison SCNT, plains bison SCNT and wisent SCNT as experimental groups. Cleavage and blastocyst rates were assessed, and blastocyst quality was determined using total cell number, apoptotic incidence and relative quantification of mitochondria‐related genes NRF1, MT‐CYB and TFAM. These results indicate that embryos can be produced by interspecies SCNT in all bison species/subspecies (13.34–33.54% blastocyst rates). Although increased incidence of apoptosis was observed in bison SCNT blastocysts compared to cattle SCNT controls (10.45–12.69 vs 8.76, respectively) that corresponded with significantly lower cell numbers (80–87 cells vs >100 cells, respectively), no major differences were observed in the expression of NRF1, MT‐CYB and TFAM. This study is the first to report the production of bison embryos by interspecies SCNT. Blastocyst development in all three bison species/subspecies was greater than the rates obtained in previous studies by IVF, which supports the potential role of SCNT for in vitro embryo production in this species. Yet, further investigation of developmental competence and the factors influencing blastocyst quality and viability is required. 相似文献
47.
Influence of stocking density on the behaviour of juvenile Litopenaeus vannamei (Boone, 1931)
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Felipe P. da Costa Brenda Suellen Franklin de Farias Gomes Silvia Dinara do Nascimento Alves Pereira Maria de Fátima Arruda 《Aquaculture Research》2016,47(3):912-924
Applied ethology can help to improve Litopenaeus vannamei aquaculture. Our purpose was to demonstrate an influence of stocking density on behaviour. The shrimp were first distributed in aquaria and observed via an ad libitum observational method to construct an ethogram of social and feeding behavioural categories. The resulting ethogram consisted of retreat, cannibalism, getting to the feeding tray, occupying the feeding tray and getting feed. We then kept shrimp in aquaria at densities of 50, 75 and 100 animals m?2 and observed them via a behavioural sampling method using our ethogram as well as focal animal sampling of behaviours derived from the literature. These literature‐derived behaviours consisted of inactivity, feeding, crawling, exploration, burying, swimming and cleaning. We found that stocking density affects the behaviour of the shrimp. Optimal searching and feeding and a low frequency of crawling and swimming occurred at a density of 50 animals m?2, indicating a higher potential for growth and welfare at this density. 相似文献
48.
Development and agronomic performance of common bean lines simultaneously resistant to anthracnose, angular leaf spot and rust 总被引:1,自引:0,他引:1
V. A. Ragagnin T. L. P. O. de Souza D. A. Sanglard K. M. A. Arruda M. R. Costa A. L. Alzate-Marin J. E. de S. Carneiro M. A. Moreira E. G. de Barros 《Plant Breeding》2009,128(2):156-163
The common bean is affected by several pathogens that can cause severe yield losses. Here we report the introgression of resistance genes to anthracnose, angular leaf spot and rust in the 'carioca-type' bean cultivar 'Rudá'. Initially, four backcross (BC) lines were obtained using 'TO', 'AB 136', 'Ouro Negro' and 'AND 277' as donor parents. Molecular fingerprinting was used to select the lines genetically closer to the recurrent parent. The relative genetic distances between 'Rudá' and the BC lines varied between 0.0% and 1.99%. The BC lines were intercrossed and molecular markers linked to the resistance genes were used to identify the plants containing the genes of interest. These plants were selfed to obtain the F2 , F3 and F4 plants which were selected based on the presence of the molecular markers mentioned and resistance was confirmed in the F4 generation by inoculation. Four F4:7 pyramid lines with all the resistance genes showed resistance spectra equivalent to those of their respective donor parents. Yield tests showed that these lines are as productive as the best 'carioca-type' cultivars. 相似文献
49.
Magnetic Field and Plasma Observations at Mars: Initial Results of the Mars Global Surveyor Mission 总被引:2,自引:0,他引:2
MH Acu?a JEP Connerney P Wasilewski RP Lin KA Anderson CW Carlson J McFadden DW Curtis D Mitchell H Reme C Mazelle JA Sauvaud C d'Uston A Cros JL Medale SJ Bauer P Cloutier M Mayhew D Winterhalter NF Ness 《Science (New York, N.Y.)》1998,279(5357):1676-1680
The magnetometer and electron reflectometer investigation (MAG/ER) on the Mars Global Surveyor spacecraft has obtained magnetic field and plasma observations throughout the near-Mars environment, from beyond the influence of Mars to just above the surface (at an altitude of approximately 100 kilometers). The solar wind interaction with Mars is in many ways similar to that at Venus and at an active comet, that is, primarily an ionospheric-atmospheric interaction. No significant planetary magnetic field of global scale has been detected to date (<2 x 10(21) Gauss-cubic centimeter), but here the discovery of multiple magnetic anomalies of small spatial scale in the crust of Mars is reported. 相似文献
50.
Streptococcus suis was recovered from 9 outbreaks of septicaemia and meningitis in weaned pigs between 1979 and 1983. Fifteen isolates from 7 outbreaks were identified as S. suis type 9, and 3 isolates from 2 outbreaks as S. suis type 2. Three further isolates of S. suis type 2 and an isolate of S. suis type 3 were recovered from cases of bronchopneumonia in weaned pigs from 4 other piggeries. 相似文献