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31.
A. Rodionov S. Nii‐Annang T. Fischer A. Gattinger O. Bens T. Raab R. F. Hüttl 《Soil Use and Management》2014,30(1):78-87
Application of hydrophilic polymers composed of cross‐linked polyacrylate can improve soil water‐holding capacity and accelerate the restoration of post‐mining substrates. In this work, we studied the persistence of a polyacrylate polymer incorporated into a soil and its impact on plant nutrients at a reclamation site of former lignite mining in Lusatia (Germany). In contrast to autumn application, the incorporation of the polymer enhanced the sequestration of plant‐derived carbon in the soil, which was reflected by a significant increase in the concentration of a lignin marker. Attenuated total reflexion–Fourier transform infrared spectra (ATR‐FTIR) and total elemental contents in the applied polymer suggested an intensive cation exchange between the polymer framework and the soil‐forming substrate. In addition, there was an enrichment of carbonaceous material, which seems to reduce the swelling and thus the water‐holding capacity of the cross‐linked polyacrylate. Conversely, this process protected the polymer structure from rapid decomposition. 相似文献
32.
David M. Jaramillo José C. B. Dubeux Jr Joao M. B. Vendramini Luana M. D. Queiroz Erick R. S. Santos Martin Ruiz-Moreno Liza Garcia Daciele Sousa de Abreu Lucas Ramos de Miranda Michelle Cristina Fernando de Siqueira 《Grass and Forage Science》2020,75(2):153-158
Nitrogen fertilization is a common practice for sustaining forage production in forage systems in southeastern United States. Warm-season annual legumes may be an alternative forage to warm-season perennial grasses that do not require N fertilization. Sunn hemp (Crotalaria juncea L.) is a fast-growing, warm-season annual legume native to India and Pakistan. The objective of this 2-year study was to assess the herbage accumulation (HA), atmospheric N2 fixation (ANF) and nutritive value of sunn hemp. Treatments were the factorial arrangement of two sunn hemp cultivars (“Crescent Sun” and “Blue Leaf”), three seeding rates (17, 28 and 39 kg seed/ha) and seed inoculation (inoculated or non-inoculated seeds), distributed in a randomized complete block design with four replicates. Crescent sun had greater HA (3,218 vs. 1764 kg DM/ha) and ANF (41 vs. 25 kg N/ha). Blue leaf had greater crude protein (CP) (188 vs. 176 g/kg) and in vitro digestible organic matter (IVDOM) concentrations (564 vs. 531 g/kg) than crescent sun. Non-inoculated seed had greater CP than inoculated seed, 188 and 177 g/kg, respectively, and inoculation did not affect HA. Intermediate seeding rate (28 kg/ha) decreased HA (2002 kg DM/ha), while HA from high and low seeding rates (17 and 39 kg/ha, respectively) did not differ (2,863 and 2,615 kg DM/ha respectively). Planting non-inoculated crescent sun at 17 kg/ha seeding rate is a feasible management practice to produce sunn hemp in subtropical regions; however, inoculation should always be recommended for proper establishment. 相似文献
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Lina Maria Correa Ricardo D. Moreno José Luis Riveros 《Reproduction in domestic animals》2021,56(4):680-683
The present study examined the effects of different photoperiods and melatonin treatment on plasma prolactin concentrations in guanacos, a South American camelid, in captivity. Fourteen adult female guanacos, not gestating or lactating and isolated from males, were studied. The control group was exposed to natural daylight, during short days (N = 7, 10L:14D) and long days (N = 7, 16L:8D). The treatment group (N = 7, 10L:14D) received melatonin implants every 23 days for 6 weeks during long days. Blood samples were taken at intervals of 1 week for 3 weeks, starting the third week of treatment. Prolactin concentrations were measured using competitive ELISA. Plasma concentrations of prolactin in non-lactating female guanacos have seasonal changes, with a higher concentration (p < .001) in short days (3.50 ± 2.24 ng/ml) than long days (1.10 ± 0.91 ng/ml). Melatonin treatment significantly decreases (p < .05) plasma concentrations of prolactin on the 21st day after the treatment. These findings are the first report of an endogenous circannual rhythm of plasma prolactin concentration and the action of melatonin treatment on prolactin secretion in this wild camelid. 相似文献
36.
Ana Rostaher Ralf S Mueller Lena Meile Claude Favrot Nina Maria Fischer 《Veterinary dermatology》2021,32(2):206-e52
A 1.5-year-old male castrated dog was presented in anaphylactic shock after suffering an apparent bee sting. Immunotherapy with bee venom was initiated based upon history, skin testing and serological testing for allergen-specific immunoglobulin (Ig)E. The dog was maintained on venom immunotherapy for five years and showed no signs of adverse effects from therapy or from repeated bee stings. 相似文献
37.
André Guimarães Maciel e Silva Suely Cristina Gomes de Lima Pedro Danilo de Oliveira Michel dos Santos Moraes Célia Maria Costa Guimarães Jamile Andréa Rodrigues da Silva Alexandre Rossetto Garcia Benjamim de Souza Nahúm Lilaine de Sousa Neres Gerlane Nunes Noronha José de Brito Lourenço Júnior 《Animal Science Journal》2021,92(1):e13576
The objective was to evaluate the effect of concentrate supplementation using by-products of the Amazonian industry on milk production, milk composition, and milk fatty acid profile of dairy buffaloes. Twelve lactating buffaloes (544.5 ± 35.6 kg, 6.4 ± 2.2 years old, 59 ± 6 days in milk) were allotted in a pasture of Mombaça grass and managed under rotational grazing (4 days occupancy/28 days rest). A 3 × 3 Latin square was adopted, and each animal alternately received three supplementary treatments based on corn bran + soybean meal or cupuaçu cake or murumuru cake for 21 days per treatment. Murumuru cake increased the levels of lauric acid and myristic acid in the milk (p < 0.05). Murumuru cake reduced the unsaturated fatty acid contents in the milk compared with animals fed control diet or cupuaçu cake (24.27% vs. 25.24% vs. 25.08%). The n-6/n-3 ratio was 2.6, 1.97, and 2.0 in the control, cupuaçu, and murumuru groups, respectively. Based on this parameter, cakes made from cupuaçu as well as murumuru could be considered to be adequate for inclusion in dairy water buffalo feed. However, the murumuru cake addition requires some caution because its use induces the secretion of higher levels of lauric and myristic fatty acids that are related to human cardiovascular disease. 相似文献
38.
Maria Johansson Sabrina Dressel Emma Kvastegård Göran Ericsson Anke Fischer Bjørn P. Kaltenborn 《Human Dimensions of Wildlife》2016,21(2):158-168
European researchers from both the natural and social sciences show growing interest in studying interactions between society and wildlife. A wealth of theoretical frameworks, concepts, and methods are used, but an integration of perspectives is lacking. This research note summarizes results from two workshops that included 63 delegates from 25 European countries, as well as a follow-up survey of 41 respondents. Two main theoretical approaches to the study of human–wildlife interactions were identified. One approach focuses on the collective societal level relying on theories of governance, social representation, deliberative procedures, and commons theory. The other approach targets individuals or groups, and is based on theories such as the cognitive hierarchy, theory of reasoned action, and theory of planned behavior. Interdisciplinary collaboration is needed to identify the best options for wildlife conservation and management in a more politically integrated Europe. 相似文献
39.
Metlholo Andries Phukuntsi Helene Brettschneider Desiré L Dalton Teresa Kearney Jacqueline Badenhorst Antoinette Kotze 《African Zoology》2016,51(1):69-76
DNA barcoding has been proposed as a method for species identification. However, this method has been criticised for its over-reliance on a single mitochondrial gene. In this study, four mitochondrial gene regions and one nuclear gene region were used to investigate their different abilities to identify tissue associated with museum specimens of Aethomys chrysophilus, Aethomys ineptus and Micaelamys namaquensis. Aethomys chrysophilus and the more recently elevated A. ineptus are indistinguishable on morphological grounds; however, their ranges are largely parapatric with only one syntopic locality currently known. All of the mitochondrial gene regions were able to separate M. namaquensis from A. chrysophilus and A. ineptus, but they varied in their abilities to resolve differences between A. chrysophilus and A. ineptus. The sequence results identified a specimen from KwaZulu-Natal that was misclassified and should have been identified as A. ineptus. Seven specimens that had not been reclassified following the elevation of A. ineptus to species level were identified as A. ineptus. Individuals of A. chrysophilus from Malawi could not be classified as either A. chrysophilus or A. ineptus, and may be a hybrid or a new, distinct species. This study indicates that DNA barcoding may be used to separate M. namaquensis from A. chrysophilus and A. ineptus, and although it was not able to separate A. chrysophilus and A. ineptus, it did indicate specimens from Malawi may be a new cryptic species. 相似文献
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