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101.
Hiam Marcon Luiz G. Griss Vitor L. Molosse Bruno G.O. Cecere Davi F. Alba Karoline W. Leal Gabriela M. Galli Carine F. Souza Matheus D. Baldissera Samanta Gundel Vitria de A. Bassotto Aline F. Ourique Marcelo Vedovatto Aleksandro S. Da Silva 《动物营养(英文)》2021,7(2):521
Curcumin-containing nanocapsule powder formulations have not been used in ruminant feed to date, despite the fact that curcumin is known to be a functional food additive. The objective of this study was to determine whether ethyl polymethacrylate (Eudragit L-100) nanocapsules loaded with curcumin (N-CU) would improve health and growth of lambs. Thirty-two male Lacaune lambs (body weight [BW] = 16 ± 0.99 kg; 45 d of age) were randomly assigned to 1 of 4 treatments: T0, T1, T2 and T4, representing supplementation of curcumin at 0, 1, 2, and 4 mg/kg concentrate, respectively. The animals in each treatment were allocated in 4 pens of 2 lambs each (8 lambs per treatment). The experiment lasted 17 d, with samples and measurements collected on d 0, 7, 12, and 17. The T2 lambs had greater average daily gain than T0 lambs. Regression analysis showed that the ideal dose of N-CU to enhance weight gain was 1.89 mg/kg concentrate. There were significant interactions (P < 0.05) between treatments × time for hematological variables, particularly for increases in erythrocytes (T2) and reductions in counts of leukocytes, neutrophils, and lymphocytes in T1 and T2. There were significant interactions between treatment × time for total protein, globulin, urea, and triglyceride levels. Stimulation of the antioxidant system was also observed. There were increased levels of non-protein thiols (NPSH), as well as increased activities of superoxide dismutase (SOD) and glutathione S-transferase (GST) in the supplemented animals. Levels of reactive oxygen species (ROS) were lower in the serum of supplemented lambs. In general, the 4 mg/kg dose had no positive effects on growth or health. This was an unexpected result, given the known properties of curcumin. Taken together, these findings suggest that addition of low concentrations of nanoencapsulated curcumin (T1 and T2) in lamb feed improves health, minimizing oxidative stress and generates anti-inflammatory effects that may have contributed indirectly to greater weight gain. Nanocapsules potentiate the effects of curcumin and may emerge as a new tool in animal nutrition. 相似文献
102.
Sample preparation affects the results of the determination of persistent organic pollutant (POP) concentrations in soils. We compared the extraction results of POPs from air‐ and freeze‐dried with field‐fresh samples. We determined the concentrations of 21 polycyclic aromatic hydrocarbons (PAHs) and 14 polychlorinated biphenyls (PCBs) in 35 horizons of forest soils (Lithosols and Cambisols) along a deposition gradient caused by a chemical factory in Strá?ske (eastern Slovakia). The organic C (Corg) concentrations of the studied samples ranged 14‐477 g kg‐1, the sum of 21 PAH (Σ 21PAHs) concentrations 53‐6870 μg kg‐1, and that of 14 PCBs (Σ 14PCBs) 0.12 96 μg kg‐1. The benzofluoranthenes were the most abundant PAHs, and the hexa‐chlorinated PCBs 138 and 153 were the most abundant PCBs. The deposition gradient was reflected by decreasing PAH and PCB storages in the organic layer with increasing distance from the chemical factory (Σ 21PAHs: 82‐238, Σ 14PCBs: 0.34‐2.3 g ha‐1). The PAH concentrations in air‐ and freeze‐dried samples were consistently lower than those in field‐fresh extracted samples. For naphthalene, this was mainly attributable to volatilization losses during drying. Naphthalene losses decreased with increasing Corg concentrations. For all other PAHs, drying reduced the extractability; the latter was correlated with the water content of the samples. The differences in most PCB concentrations among the sample preparation methods were small (within the determination error of ±15 %) and inconsistent. However, PCBs 8, 28, 52, and 209 had markedly higher concentrations in dried than in fieldfresh extracted samples. The increased recovery of low‐chlorinated PCBs in dried samples may be explained by redistribution of PCBs from higher to lower contaminated samples via the drying room atmosphere because there were no PCBs in analytical blanks. This assumption is supported by a close correlation between the octanol‐air distribution coefficient and the up to hexa‐chlorinated PCB concentrations (normalized to those in field‐fresh extracted samples) in air‐ (r = ‐0.90) and freeze‐dried (r = ‐0.86) samples. Our study shows that each sample preparation method has its specific advantages and disadvantages. Sample drying results in a standardization to a well‐defined water content and facilitates homogenization; therefore it increases the reproducibility of POP determinations. Extraction of field‐fresh samples reduces volatilization losses and contamination risks. 相似文献
103.
The occurrence of friabilins in triticale and their relationship with grain hardness and baking quality 总被引:3,自引:0,他引:3
Ramírez A Pérez GT Ribotta PD León AE 《Journal of agricultural and food chemistry》2003,51(24):7176-7181
Grain hardness is a quality parameter in wheat and other cereals. In wheat, a group of M(r) 15 000 proteins called friabilins have been shown to be related to grain hardness. The objective of this study was to determine the presence of friabilins on starch granules of different triticale lines and their relationship with grain texture and baking quality. The triticale lines studied have a wide range of hardness, which presented correlation with baking quality parameters such as damaged starch and solvent retention capacity. All of the triticale lines contained friabilins on the starch granules. However, the correlation between hardness and friabilin content was not observed, suggesting that these proteins would not be directly involved in grain texture determination of triticale. Consequently, friabilin content did not have any relation with cookie quality in triticale flours, but it could be related to breadmaking quality because it has a positive correlation with the sodium dodecyl sulfate sedimentation index. 相似文献
104.
在美国俄勒冈州,浮石在种苗生产上应用很广泛,但是人们对于浮石的特性知之甚少,也不清楚它是怎样影响种苗植株生长的。本文对浮石的地质学、化学和物理学特征进行了描述,并讨论了这些特性在种苗植株生长过程中所起的潜在作用。该项研究在俄勒冈州苗圃协会的大力资助下完成。什么是浮石?浮石是一种多孔渗水、质地轻的岩石,外表上与珍珠岩相似。pumice这个词来源于拉丁语中的pumex,是泡沫的意思。浮石是一种火成岩,由熔化或半熔化物质形成。一些火成岩是由地表下岩熔物冷却形成的称为深成火成岩。深成火成岩因为降温过程十分缓慢,所以含有大量… 相似文献
105.
Traditionally, barley in Argentina has been cultivated in low-yielding environments. A study was conducted to test whether
breeding for improved performance under these conditions would have also improved the responsiveness to nitrogen availability.
Four cultivars of two-rowed malting barley (released in 1944, 1960,1982 and 1998) were grown under 4 rates of nitrogen fertilizer
at sowing (20, 50, 110and 160 kgN ha-1). All cultivars increased their yield with the increase in soil nitrogen. But yield of modern cultivars responded more strongly
than yield of old ones. For modern cultivars, increase in grain yield was of 12 ± 0.6 kgha-1 for each 10 kg ha-1 of increase in the mean yield (environmental index). Absolute values of genetic gain were related to nitrogen availability:
1.59, 2.58, 4.52 and 4.29 g m-2 year-1 for the N20, N50, N110 and N160 treatments, respectively. Grain yield was associated with grain number m-2, which was dependent on spikes m-2 and grains spike-1. Total biomass at maturity also explained the changes in yield. It is concluded that selection under stress conditions was,
in this case, beneficial to identify cultivars with high yields under a wide range of nitrogen availabilities.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
106.
Leite da Silva Wilian Aparecido Poehland Ralf Carvalho de Oliveira Caroline Ribeiro Ferreira Mariane Gabriela Cesar Garcia de Almeida Ricardo Cáceres Mirela Brochado Souza Macedo Gustavo Guerino da Costa e Silva Eliane Vianna Alves Fabiana Villa Nogueira Eriklis de Andrade Melo-Sterza Fabiana 《Tropical animal health and production》2020,52(5):2273-2281
Tropical Animal Health and Production - The aim of this study was to evaluate the impact of increased shadow supply in integrated crop-livestock-forest systems on in vitro embryonic development and... 相似文献
107.
Matheus Gomes da Cruz Gabriela Tomas Jernimo Sunique Po Cordeiro Bentes Ligia Uribe Gonalves 《Journal of fish diseases》2022,45(1):203-212
This study investigated the in vitro and in vivo efficacy of trichlorfon against Dawestrema cycloancistrium, as well as its physiological effects on arapaima. Naturally parasitized arapaima gill arches were exposed in vitro to 100, 250, 500 and 750 mg/L of trichlorfon and a control group (only distilled water), in triplicate. Parasites were monitored, and mortality was used to determine the median effective concentration (EC50). The 750 mg/L concentration demonstrated 100% in vitro efficacy against D. cycloancistrium after 60 min, while the intermediate (500 mg/L) and the lowest (100 and 250 mg/L) tested concentrations were completely efficient after 90 and 130 min, respectively. The EC50-1h of trichlorfon for D. cycloancistrium was determined at 171.73 mg/L. Parasitized arapaima juveniles were exposed to a control group and 150 mg/L of trichlorfon in triplicate. Fish were exposed to two therapeutic baths for 60 min with 24-h intervals between treatments. Therapeutic baths with 150 mg/L of trichlorfon were 92.99% effective against D. cycloancistrium and did not bring about haematological alterations (erythrogram, white blood cell count, thrombogram, plasma glucose and total proteins). Therefore, 150 mg/L of trichlorfon can be used in therapeutic baths to control and treat D. cycloancistrium infestations with no physiological impairments for arapaima. 相似文献
108.
Luis Jimnez-Yan Abelardo Brito Gerard Cuzon Gabriela Gaxiola Toms García Gabriel Taboada Luis A. Soto Roberto Brito 《Aquaculture (Amsterdam, Netherlands)》2006,260(1-4):337-345
L. vannamei postlarvae are normally raised with a protein dense diet (50% protein) rich in fishmeal. Part of the protein is utilized for energy purpose instead of protein synthesis. Based on a previous energy partitioning study, the effects of two isoenergetic compounded feed treatments – animal protein (AP) and vegetable protein and carbohydrates (VPC) – upon growth efficiency and energy budget of shrimp postlarvae and early juveniles were determined. Recovered energy (RE) or production (P) after 50 days trial was similar (2 J day− 1) in both treatments, from PL14 to PL19. However, early juveniles discriminated between animal protein (116 J day− 1) and vegetable protein and carbohydrates (88 J day− 1). The difference in respiration indicated a higher heat increment with AP compared to VPC. At maintenance level, energy used was lower with AP than VPC treatment. Postlarvae and early juveniles employed protein as a main energy substrate (O:N < 20). Differences in the efficiencies observed in the calculated energy budget were attributed to the presence of carbohydrates in diet and not to the protein source. The advantage of incorporating vegetable protein source in the diet of harvesting shrimp may eventually contribute towards a reduction of fishmeal costs and waste products as well as to achieve sustainable shrimp farming. 相似文献
109.
Gabriela R. Lemos Mendes Chiara Leal Alves Paola Lopes Cavalheiro Cristiana Costa Bretanha Fernanda Arnhold Pagnussatt Eliana Badiale‐Furlong 《Cereal Chemistry》2015,92(6):611-616
Fusarium verticillioides is one of the most important pathogens in maize and is a producer of fumonisin B1 (FB1). Although reports of its presence in wheat are scarce, the susceptibility of this cereal to fungus of the same genus motivates interest in investigating compounds present in the grain with inhibitory activity against this species. The aim of this study was to extract α‐amylase inhibitors from wheat and apply them in vitro to evaluate its effect on the development and expression of toxigenic potential of F. verticillioides. The α‐amylase inhibitors, both crude (P0) and purified (P1), were applied to in vitro culture containing a pathogen mycelium disc. Mycelial growth of the pathogen, glucosamine content, α‐amylase activity, and production of FB1 were investigated. All protein extracts of wheat showed the ability to inhibit pathogen growth, especially the extract P0 from cultivar Quartzo, which resulted in a reduction of glucosamine content (66%) and α‐amylase activity (84%). Furthermore, the protein inhibitors showed antifumonisin effect, reducing by 33 and 47% the mycotoxin production when applied as P0 and P1, respectively. These results suggest that α‐amylase inhibitor contributed to resistance against pathogen attack, acting in a diversified manner for each fungal species. 相似文献
110.
Guimarães Ade S Gouveia AM do Carmo FB Gouveia GC Silva MX Vieira Lda S Molento MB 《Veterinary parasitology》2011,176(2-3):265-269
Parasitic infection is recognized worldwide as a limiting factor in the production of goats, and various control methods are used to reduce economic losses, often without considering the epidemiology of the parasites. This has led to the development of highly tolerant parasite populations and the presence of chemical residues in the beef and milk. The objective of this study was to determine the level of knowledge of goat farmers about parasitic diseases and to correlate this with the epidemiology of endoparasites and parasite control practices in goat farms in the state of Minas Gerais, Brazil. The analysis was based on a questionnaire applied by trained veterinarians. The sample was homogeneous throughout the state, covering 18.4% (157/853) of municipalities. Eighty-four dairy goat farms in 81 municipalities and 200 properties with beef goats in 76 municipalities were evaluated. The herd size per goat farm ranged from 4 to 57 (average 24) for beef herds and from 2 to 308 (average 63) for dairy farms. The majority of the beef herd production was extensive and semi-extensive (98.5%), while the dairy herds were maintained under intensive farming (98.8%). The mixed production of goats and sheep was reported by 36.5% of beef goat farmers and by 20.2% of dairy goat farmers. Among the beef goats farms on which the technological level was determined, 2.0% were categorized as having high technological level, 34.5% as medium, and 63.5% as low. Of the 84 dairy farms, 30% operated at a high, 47% at a medium, and 23% at a low technological level. The adoption of practices to reduce parasitism, such as the quarantine of animals, treatment of newly arrived animals, regular cleaning of the floor, and technical assistance, was significantly higher on dairy farms than on beef farms. Although 85.7% of dairy farmers and 83% of beef farmers medicate their animals, the treatments were performed without technical criteria, and deworming intervals ranged from 30 to 120 days or more. The average interval between treatments was significantly longer in dairy goat herds (4.8 months) than in the beef herds (3.6 months). The most commonly used drugs were macrocyclic lactones (37.7% in dairy and 39.5% in beef herds) and benzimidazoles (48.9% in dairy and 31.5% in beef herds). Goat production in Minas Gerais is still in its infancy, and even though using a control program associated with other health practices, producers still rely heavily on chemicals to get satisfactory results. 相似文献