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991.
L. A. Valente Almeida J. Santos Oliveira P. Lynce de Faria 《Plant foods for human nutrition (Dordrecht, Netherlands)》1976,26(4):349-363
The influence of dicyanodiamidine sulphate (DDS) on the quality of some cereal crops was studied in several pot experiments. In each of the experiments DDS was compared with ammonium sulphate (AS) and mixtures of AS + DDS in several proportions. The experiments were carried out in several soils and the influence of soil characteristics were evident in the final results. The cereals studied were sorghum, wheat, rye, barley and fescue. Influence of different treatments was studied in relation to the composition either of whole plants, or of straw and grain separately.Application of DDS is especially important for protein content and quality of products. The utilization of this fertilizer is rather slow and continuous during the vegetative cycle of plants, and as a consequence protein synthesis is mainly increased specially in the grain. Protein quality in wheat may or may not be affected depending upon the exchange capacity of the soil. In cereals used for pasture and subjected to several cuts the influence of DDS is also important, decreasing differences in production and quality among the different cuts, particularly noticeable in the summer cuts. Mineral composition of plants is also affected by DDS.The conclusion that can be drawn is that DDS, in mixtures with AS, may be a very important tool in nitrogen fertilization mainly on light soils, long term crops and under conditions of heavy rains, circumstances where its more or less continuous utilization and resistance to leaching are important features to be considered in production and for the quality of the products.
Professor of Agricultural Chemistry. Deceased on 5th October 1975. 相似文献
Zusammenfassung Der Einfluß von Dicyandiamidinsulfat (DDS) auf die Qualität einiger Cerealien wurde in mehreren Gefäßversuchen untersucht. In jedem dieser Versuche verglich man DDS mit Ammoniumsulfat (AS) und mit Mischungen von AS + DDS in verschiedenen Proportionen. Die Versuche wurden in mehreren Böden durchgeführt. In den Endergebnissen kam der Einfluß der charakteristischen Bodeneigenschaften gut heraus. Die im Versuch stehenden Cerealien waren Sorghum, Weizen, Roggen, Gerste und Wiesenschwingel (Festuca). Der Einfluß der verschiedenen Behandlungen konnte durch die chemische Zusammensetzung der ganzen Pflanze oder getrennt nach Stroh und Korn verfolgt werden.Die Verabfolgung von DDS ist insbesondere für den Eiweißgehalt und für die Qualität der Erzeugnisse bedeutsam. Die Ausnutzung dieses Düngers ist während der vegetativen Entwicklung ziemlich langsam und andauernd, infolgedessen ist die Eiweißsynthese speziell im Korn besonders erhöht. Eiweißqualität kann oder kann nicht im Weizen beeinflußt werden. Dies hängt von der Austauschkapazität des Bodens ab. In Cerealien für Weidezwecke fand man bei verschiedenen Schnitten ebenfalls einen bedeutenden Einfluß von DDS. Unterschiede in Menge und Qualität zwischen den verschiedenen Schnitten wurden vermindert, insbesondere beim Sommerschnitt. Auch die Mineralstoffzusammensetzung der Pflanzen konnte durch DDS beeinflußt werden.Zusammenfassend kann gesagt werden, daß sich DDS zur Stickstoffdüngung zusammen mit AS hauptsächlich auf leichten Böden sehr nützlich erweisen kann, ebenso bei Pflanzen mit langer Vegetationszeit und bei schweren Regenfällen, also bei Bedingungen, wo es mehr oder weniger auf laufende Nährstoff-Ausnutzung und auf Verhinderung der Nährstoffauswaschung ankommt. Dies sind wichtige Fakten für die Erzeugung und für die Qualität der Produkte.
Resumé L'influence du sulfate de dicyanodimidine (SDD) dans la qualité de quelques céreales a été étudiée dans des essais en pots. Le SDD a été comparé dans tout les cas avec le sulfate d'ammonium (SA) et avec des mélanges SA+SDD.Ces essais ont été conduits sur différents types de sols et on a vérifié l'influence des caractéristiques du sol dans la production et dans la qualité des produits. Les céreales qui ont été essayés sont le sorghum, le blé, le seigle, l'orge et la fétuque. L'influence des traitements a été étudiée soit sur la composition chimique de la plante intiére soit sur la composition de la tige et du grain en séparé. Le SDD influence notamment la teneur et la qualité des protéines. On vérifie que ce produit est utilisé par les plantes d'une façon lente et continuelle tout au ling de son cycle de végétation et, en conséquence la synthèse des proteínes du grain est assez béneficiée. Dans le cas du blé on a verifié que la qualité des proteínes est diminuée ou non selon la capacité d'échange du sol. Dans les céreales utilisés comme paturage l'influence du SDD est aussi importante, en diminuant les variations de production et de la qualité parmis les différents coupes, notamment en ce qui concerne la production d'Eté. La composition minérale est aussi modifiée par le SDD.On a conclus que le SDD, en mélange avec le SA, peût constituer un important instrument de la fertilization azotée, surtout dans des sols légers, avec une pluviosité importante et dans des cultures de longue permanence dans le sol, parce que dans ces cas l'utilization plus ou moins continuelle et graduelle du SDD et sa résistance au lessivage lui permêt de représenter un rôle important dans l'amélioration de la production et de la qualité des produits.
Professor of Agricultural Chemistry. Deceased on 5th October 1975. 相似文献
992.
Among the current methyl bromide alternatives under study, propylene oxide has shown potential to control soilborne diseases, nematodes, and weeds in polyethylene-mulched tomato (Lycopersicon esculentum Mill.). Therefore, field trials were conducted to determine the most effective propylene oxide doses against populations for the nematode Belonolaimus spp. and the weed Cyperus spp. and their effect on nutrient uptake. Propylene oxide doses were 0, 190, 380, 570, 760, and 950 L/ha. Data indicated that populations of Belonolaimus and Cyperus rapidly decreased with 570 L/ha of propylene oxide. Propylene oxide doses also affected foliar concentrations of phosphorus and potassium. There was a linear increase of phosphorus concentration as dose increased, whereas potassium concentration increased rapidly after 190 L/ha of propylene oxide. The highest tomato yields were obtained with application of 760 and 950 L/ha of propylene oxide. 相似文献
993.
Camara RB Costa LS Fidelis GP Nobre LT Dantas-Santos N Cordeiro SL Costa MS Alves LG Rocha HA 《Marine drugs》2011,9(1):124-138
Fucan is a term used to denominate a family of sulfated polysaccharides rich in sulfated l-fucose. We extracted six fucans from Canistrocarpus cervicornis by proteolytic digestion followed by sequential acetone precipitation. These heterofucans are composed mainly of fucose, glucuronic acid, galactose and sulfate. No polysaccharide was capable of prolonging prothrombin time (PT) at the concentration assayed. However, all polysaccharides prolonged activated partial thromboplastin time (aPTT). Four sulfated polysaccharides (CC-0.3/CC-0.5/CC-0.7/CC-1.0) doubled aPTT with only 0.1 mg/mL of plasma, only 1.25-fold less than Clexane, a commercial low molecular weight heparin. Heterofucans exhibited total antioxidant capacity, low hydroxyl radical scavenging activity, good superoxide radical scavenging efficiency (except CC-1.0), and excellent ferrous chelating ability (except CC-0.3). These results clearly indicate the beneficial effect of C. cervicornis polysaccharides as anticoagulants and antioxidants. Further purification steps and additional studies on structural features as well as in vivo experiments are needed to test the viability of their use as therapeutic agents. 相似文献
994.
Lílian da Silva Fialho Valéria Monteze Guimarães Everaldo Gonçalves de Barros Maurilio Alves Moreira Luiz Antônio dos Santos Dias Maria Goreti de Almeida Oliveira Inês Chamel José Sebastião Tavares de Rezende 《Plant foods for human nutrition (Dordrecht, Netherlands)》2006,61(2):83-85
Common beans have a high nutritional value, but contain galactooligosaccharides (GO), which cause flatulence and intestinal discomfort in humans. The biochemical composition of ten bean cultivars was determined to select those of high protein and low GO contents. The cultivars varied in carbohydrate (47.02–60.17%), GO (3.12 – 5.71%), protein (22.17–33.50%), lipid (1.13–1.81%), moisture (11.42–12.93%) and ash contents (4.08–5.61%). ‘Mexico 222’ presented the highest α-galactosidase activity. Protein and GO contents were positively correlated. ‘Perry Marrow’ combined high protein and low GO concentrations, indicating it can be used in improvement programs aiming at high-quality cultivars for human consumption. 相似文献
995.
Ícaro dos Santos Cabral José Augusto Gomes Azevêdo Flávio Moreira de Almeida Luiz Gustavo Ribeiro Pereira Gherman Garcia Leal de Araújo Cristiane Leal dos Santos Cruz Abdon Santos Nogueira Lígia Lins Souza Gisele Andrade de Oliveira 《Tropical animal health and production》2013,45(8):1737-1743
The objective of this study was to evaluate the effects of supplying the by-product of peach-palm (Bactris gasipaes) on performance and characteristics of carcass and non-carcass components of feedlot lambs. Twenty Santa Ines lambs of 150 days average age and 22.4?±?3.4 kg body weight were confined in individual pens. A completely randomized design was utilized with four experimental diets composed of: fresh peach-palm by-product enriched with urea, fresh peach-palm by-product + concentrate, silage of peach-palm by-product + concentrate, and silage of peach-palm by-product enriched with 15 % corn meal + concentrate. Intake was evaluated daily, and at the end of 42 days of experiments, lambs were slaughtered and the characteristics of carcass and non-carcass parts were evaluated. Performance and carcass characteristics showed differences between the animals’ intake of total mixed rations (TMR) and only the diet with roughage. For the lambs that intaked TMR, the form of utilization of roughage (fresh or as silage) affected animal performance but did not change the carcass characteristics. Dry matter intake and feed conversion were influenced by the form of utilization of the silage (with and without additive). Providing fresh by-product plus concentrate improves lamb performance but does not interfere in the carcass characteristics, compared with the use of by-product in the form of silage. 相似文献
996.
Martín Santos González Blanca Torrent Bertrán de Lis Francisco J Tendillo Cortijo 《Veterinary anaesthesia and analgesia》2013,40(4):399-402
ObjectiveTo describe the use of intramuscular (IM) premedication with alfaxalone alone or in combination with diazepam in pigs.Study designRandomised‐controlled trial.AnimalsTwelve healthy 2 month‐old Landrace x Large White pigs weighing 21.3 ± 2.4 kg.MethodsAnimals were distributed randomly into two groups: group A (n = 6) 5 mg kg?1 of IM alfaxalone; and group AD (n = 6) 5 mg kg?1 of IM alfaxalone + 0.5 mg kg?1 of IM diazepam mixed in the same syringe. The total volume of injectate was standardized at 14 mL by dilution in 0.9% sodium chloride. Pain on injection, the degree of sedation and the quality of and time to induction of recumbency were evaluated. Once pigs were recumbent, reflexes were evaluated. Pulse and respiratory rates and arterial oxygen saturation were recorded at 5 and 10 minutes after drug administration. Pigs were then moved to another room for subsequent anaesthesia.ResultsTwo animals of group A and one of group AD showed slight pain on drug injection. Time to lateral recumbency (in seconds) was shorter in group AD (mean 203 ± SD 45 range 140–260) than group A (302 ± 75, range 220–420; p < 0.05). In group AD sedation was deeper, and on recumbency there was better muscle relaxation. When moved for anaesthesia, two pigs in Group A showed slight resistance but did not vocalize. There were no differences in physiologic measurements between groups, although in both groups, respiratory rate was significantly lower at ten compared with five minutes post drug injection. There was no apneoa.Conclusions and clinical relevanceIM administration of alfaxalone combined with diazepam resulted in a rapid onset of recumbency and deep sedation, with minimal side effects. The combination might be useful for premedication, but volume of injectate will limit its use to small pigs. 相似文献
997.
Rentsenkhand SAMBUU Mitsuhiro TAKAGI Zhao NAMULA Masahiro NII Masayasu TANIGUCHI Seiich UNO Emiko KOKUSHI Chenga TSHERING Regiane Rodrigues dos SANTOS Johanna FINK‐GREMMELS Takeshige OTOI 《Animal Science Journal》2013,84(1):28-34
The effects of in vitro exposure of porcine spermatozoa to zearalenone (ZEN) and α‐zearalenol (α‐ZOL) were studied by evaluating several parameters of an in vitro fertilization (IVF) system. For this purpose, boar spermatozoa cultured with semen storage medium containing 0 (control), 10 and 1000 µg/L of ZEN and α‐ZOL for 1 week at 5°C were used for IVF of in vitro matured oocytes. Overall, there were no significant differences in the rates of total penetration, monospermic fertilization, and polyspermic fertilization of oocytes inseminated with spermatozoa from the different groups. Similarly, ZEN and α‐ZOL at 10 and 1000 µg/L did not have detrimental effects on the cleavage and development to blastocysts of oocytes after in vitro fertilization. Although the motility, viability, and plasma membrane integrity of spermatozoa significantly decreased after 3 weeks of storage compared to non‐stored spermatozoa (P < 0.05), ZEN and α‐ZOL at the evaluated concentrations did not exert detrimental effects on the above parameters, even after 3 weeks of storage. These results indicate that prolonged exposure of boar spermatozoa to ZEN and α‐ZOL up to 1000 µg/L under reduced metabolic conditions does not affect their in vitro function. 相似文献
998.
A.M. Felício L.G. Gaya J.B.S. Ferraz C.T. Moncau E.C. Mattos N.P. Santos T. Michelan Filho J.C.C. Balieiro J.P. Eler 《Livestock Science》2013,157(1):81-87
Broiler feed efficiency and meat quality are the primary factors considered by the poultry industry. This study was conducted to estimate heritability and genetic correlation coefficients for skeletal muscle fiber number, area and diameter and performance and meat quality traits of Pectoralis major in a single male broiler line. (Co) variance components were estimated by restricted maximum likelihood method, using the software MTDFREML. The numerator relationship matrix was composed by 77,474 individuals. Heritability coefficient estimates ranged from moderate to high for juvenile BW, breast weight, ultrasound record of pectoral muscle, lightness and thawing meat loss. Genetic correlation estimates for performance and skeletal muscle fiber traits indicated that selection for higher breast weight and juvenile BW could reduce muscle fiber number and increase muscle fiber diameter and area, which could prejudice the meat quality of this line. Selection for muscle fiber number and against muscle fiber diameter and area might improve meat water retention ability and tenderness in this broiler line, and selection programs could consider those traits as selection criteria, although this may be costly. We recommend the evaluation of the indirect selection caused by the use of the performance traits as selection criteria especially for juvenile BW and breast weight. Direct, intense selection for both traits might be unfavorable for most of the meat quality traits analyzed, which could lead to losses to both the chicken meat processing industry and consumers. 相似文献
999.
L.D.S. Mariz S.C. Valadares FilhoE. Detmann O.G. PereiraL.G.R. Pereira M.I. MarcondesS.A. Santos F.A.C. VilladiegoD. Zanetti L.F. PradosA.N. Nunes 《Livestock Science》2013,155(1):71-76
Sugar cane is widely used in an in natura forage in tropical countries, but the adoption of silage methods facilitates the preservation of its nutritional value and improves the logistics of its use. To explain differences in performance using alternative forages, it is important to conduct studies that evaluate the various digestion sites for the nutrients provided in diets. However, considering that the collection of omasal digesta is quite laborious and requires the use of a vacuum pump, reticular sampling has been suggested as a promising alternative. Thus, the objective of this study was to evaluate the intake and ruminal digestibility obtained from samples of digesta collected in the reticulum and omasum of cattle fed different diets. Five rumen-fistulated crossbred cattle with an average initial live weight of 336±16.6 kg were used, being distributed in a 5×5 Latin square design. Five diets were evaluated, which contained 60% forage and 40% concentrate on dry matter basis using different forages: maize silage (CS); sugar cane in natura (SCIN); sugar cane silage (SCS0%); sugar cane silage treated with 0.4% calcium oxide (SCS0.4%) or 0.8% calcium oxide (SCS0.8%) on wet basis. The percentage of crude protein (CP) in all of the forages was corrected to 11% based on dry matter (DM) using a mixture of urea/ammonium sulfate (9:1). Six collections of reticular and omasal digesta were obtained over three days at 12 h intervals. To calculate the flow of reticular and omasal nutrients, a double marker system was employed, using cobalt–EDTA and indigestible neutral detergent fiber (NDFi) as markers. The reticular and omasal digesta were similar (P>0.05) to estimate ruminal digestibility of DM, organic matter (OM), CP, neutral detergent fiber (NDF) and non-fiber carbohydrates (NFC). However, the ruminal digestibility of ether extract (EE) and the intestinal digestibility of CP and EE differed (P<0.05) between sampling sites. The results indicate that the omasal digesta is more suitable than the reticular digesta for measuring the ruminal digestion of diet components. 相似文献
1000.
J. T. Paiva H. R. Oliveira M. Nascimento A. C. C. Nascimento H. T. Silva R. F. Henriques 《British poultry science》2020,61(1):3-9
ABSTRACT1. The aim of this study was to investigate the associations between several carcass, performance and meat quality traits in broilers through factor analysis and use the latent variables (i.e. factors) as pseudo-phenotypes in genetic evaluations.2. Factors were extracted using the principal components method and varimax rotation algorithm. Genetic parameters were estimated via Bayesian inference under a multiple-trait animal model.3. All factors taken together explained 71% of the original variance of the data. The first factor, denominated as ‘weight’, was associated with carcass and body weight traits; and the second factor, defined as ‘tenderness’, represented traits related to water-holding capacity and shear force. The third factor, ‘colour’, was associated with traits related to meat colour, whereas the fourth, referenced as ‘viscera’, was related to heart, liver and abdominal fat.4. The four biological factors presented moderate to high heritability (ranging from 0.35 to 0.75), which may confer genetic gains in this population.5. In conclusion, it seems possible to reduce the number of traits in the genetic evaluation of broilers using latent variables derived from factor analysis. 相似文献