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21.
Riley encased methodology: principles and processes of mangrove habitat creation and restoration 总被引:5,自引:0,他引:5
Riley encased methodology (REM) was developed for the purpose of establishing mangroves along highenergy shorelines, revetments, and bulkheads where natural recruitment no longer occurs and where conventional planting methods are ineffective. The principles of REM include the processes of individual seedling isolation within tubular encasements and adaptation of the juvenile plant to the external environment of the restoration site. The success of REM results from specifications for encasement preparation, propagule or seedling selection, and positioning of both encasements and seedlings according to elevation and tidal regimes. 相似文献
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Camila Almeida dos Santos Rafael Cassador Monteiro Bruno Grossi Costa Homem Lucero Sarabia Salgado Daniel Rume Casagrande José Marques Pereira Cláudia de Paula Rezende Bruno José Rodrigues Alves Robert Michael Boddey 《Grass and Forage Science》2023,78(1):147-160
The use of forage legumes to contribute biologically fixed nitrogen (N) to pastures is an alternative to increase beef cattle production in tropical regions. The objective was to compare the impact of the introduction of a legume with that of N fertilizer application on forage and animal production in Brachiaria pastures. This two-year study assessed three pasture treatments: (1) mixed Marandu palisadegrass (Brachiaria brizantha [syn. Urochloa brizantha] cv. Marandu) and the legume “ovalifolium” (Desmodium ovalifolium) cv. Itabela (Mixed), (2) Marandu palisadegrass pastures with 150 kg N ha−1 (Fertilized), and (3) Marandu palisadegrass without N fertilizer (Unfertilized). Rotational stocking with a variable stocking rate was used with a target herbage allowance of 1.0 kg forage kg body weight−1. The pre-grazing green herbage mass was similar for Fertilized and Mixed pastures, with 54% and 63% more mass than Unfertilized pasture, respectively (p < .001). Cattle that grazed the fertilized pasture had the greatest average daily gain (ADG; p = .017). The stocking rate and liveweight gain per area were greatest for the Fertilized and Mixed pastures (p < .001 and p < .001, respectively). No differences between treatments were found for DM forage intake (p = .555). Organic matter digestibility was lowest (p < .001) for the Mixed pasture. The inclusion of the ovalifolium legume in the Marandu pasture had the same impact on beef cattle production as annual fertilization with 150 kg N ha−1. The potential and environmental benefits of ovalifolium are discussed. 相似文献
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Breno S. Salgado Lidianne N. Monteiro Márcia M. Colodel Fernanda C. Figueiroa Luisa M. Soares Suely Nonogaki Rafael M. Rocha Noeme S. Rocha 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2013,42(3):382-385
Mammary invasive micropapillary carcinoma is a rare variant of mammary carcinoma that was recently recognized in dogs. The cytologic features and biologic behavior of such neoplasms in dogs have not yet been widely discussed in the veterinary literature. We report the clinical, cytologic, and histologic features of a canine micropapillary carcinoma in a 13‐year‐old female mongrel dog. The mammary region presented with extreme local pain, severe edema and erythema, and multifocal epidermal ulceration, which is typical for an inflammatory mammary carcinoma. Fine‐needle aspirates were highly cellular and consisted of individual cells and papillary cell clusters with characteristics of malignant epithelial cells. Histologic examination revealed neoplastic cells arranged in small papillae without fibrovascular cores, sometimes inside clear lymphatic spaces, indicating lymphovascular invasion. Regional lymph node evaluation revealed metastatic cells. Due to deteriorating clinical condition the dog was euthanatized 5 months after mastectomy. At necropsy, metastatic neoplastic mammary cells were found in popliteal and mediastinal lymph nodes, the right femoral biceps muscle, liver, heart, lungs, and urinary bladder. 相似文献
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Keid LB Soares RM Vasconcellos SA Megid J Salgado VR Richtzenhain LJ 《Research in veterinary science》2009,86(1):22-74
The performance of the rapid slide agglutination test, with and without 2-mercaptoethanol (RSAT and 2ME-RSAT) and agar gel immunodiffusion test (AGID) was evaluated for the diagnosis of brucellosis in naturally infected dogs. The microbiological culture, PCR and clinical parameters were used as reference. A total of 167 dogs were clinically examined and tested by blood culture, culture of semen/vaginal swab and PCR in blood and semen/vaginal swab. According to the results observed the 167 dogs were divided into three groups: Brucella canis infected dogs (Group 1), B. canis non-infected dogs (Group 2) and dogs with suspected brucellosis (Group 3). The dogs were then tested by RSAT, 2ME-RSAT and AGID. Groups 1 and 2 were used to calculate the diagnostic sensitivity and specificity of the serological tests and the results observed in Group 3 were also discussed. The diagnostic sensitivity of RSAT, 2ME-RSAT and AGID was respectively 70.58%, 31.76%, and 52.94%. The diagnostic specificity of RSAT, 2ME-RSAT and AGID was respectively 83.34%, 100%, and 100%. In dogs with suspected brucellosis 15% were RSAT positive, none was 2ME-RSAT positive and 5% were AGID positive. Although the serological tests are the most commonly used methods for brucellosis diagnosis, a significant proportion of false-negative results were observed highlighting the importance of the direct methods of diagnosis, like blood culture and PCR to improve the diagnosis of canine brucellosis. 相似文献
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Liposomes are artificial membrane vesicles that can be used to test and model the functions and interactions of various biological membranes, or as a carrier system to deliver biologically active substances into the cells, or to incorporate lipids into the plasma membrane of target cells to modify membrane structure–function relationships. Sperm plasma membrane undergoes lipid modification during maturation in epididymis and during capacitation in the female reproductive tract to facilitate fertilization. Natural variation in the amounts and composition of lipids in the sperm plasma membrane may also contribute to the species‐specific sperm sensitivities to handling and storage conditions. Boar sperm are notoriously susceptible to membrane damage and are resistant to compositional alteration by artificial liposomes. This study used flow cytometry to demonstrate stable incorporation of nanoliposomes prepared from a complex mixture of various phospholipids (phosphatidylcholine : phosphatidylethanolamine : sphingomyelin : phosphatidylserine : phosphatidylinositol) with high fusion efficiency. Over 90% of sperm rapidly took up fluorescently labelled liposomes and retained the lipids for at least 60 min, in a significant time‐ and concentration‐dependent manner. This unique fusion efficacy could be used to alter sperm plasma membrane composition and hence membrane‐based functional responses. 相似文献
29.
Effects of Growth Hormone on In Situ Culture of Bovine Preantral Follicles are Dose Dependent 下载免费PDF全文
CR Jimenez JL de Azevedo RG Silveira J Penitente‐Filho EL Carrascal‐Triana AM Zolini VR Araújo CAA Torres 《Reproduction in domestic animals》2016,51(4):575-584
The objective of this study was to evaluate different concentrations of growth hormone (GH) on the development of bovine preantral follicles cultured included in the ovarian tissue (in situ) on the rates of morphologically normal, viable, primordial and developing follicles, as well as the oocyte and follicle diameter and ultrastructural analysis. Ovarian fragments collected from cows with no cross‐breeds defined were cultured in situ for 1 and 7 days in minimal essential medium (α‐MEM+) supplemented with different concentrations of recombinant human GH (0, 10, 25, 50 ng/ml). The ovarian fragments non‐cultured (control) and cultured were processed for classic histology, mechanical isolation and electron transmission microscopy (MET). The parameters underwent anova (Tukey′s and Dunnett′s tests) and chi‐square test (χ2). After 7 days of culture, the treatment with 50 ng/ml GH showed no differences with fresh control (p > 0.05) and had greater effectiveness than in the 0, 10 and 25 ng/ml GH concentrations of the morphologically normal follicles. Regarding the primordial follicles, a reduction was observed in the 50 ng/ml GH concentration concomitant with the significant increase in developing follicles, differing from both the fresh control and the other GH concentrations tested. In addition, 50 ng/ml GH showed a larger follicle and oocyte diameter when compared to the other treatments cultured. Similar structures were ultrastructurally observed in the control group, 50 ng/ml GH. Follicles cultured in 10 ng/ml GH showed nuclear invagination, vacuoles and lesioned basal membrane. Hence, it is concluded that 50 ng/ml GH is the most effective concentration for the development of preantral follicles cultured in situ. 相似文献
30.
OBJECTIVE: To measure activities of NADPH-dependent reductases and sorbitol dehydrogenase in lenses from healthy dogs and cats. SAMPLE POPULATION: Lenses from 37 dogs and 23 cats. All animals were healthy and had serum glucose concentrations within reference limits. PROCEDURE: Lenses were homogenized, and activities of NADPH-dependent reductases and sorbitol dehydrogenase were measured spectrophotometrically. RESULTS: Activities of NADPH-dependent reductases and sorbitol dehydrogenase were significantly lower in lenses from cats than in lenses from dogs. However, the ratio of NADPH-dependent reductases activity-to-sorbitol dehydrogenase activity was significantly higher in lenses from cats than in lenses from dogs. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicate that during periods of hyperglycemia, sorbitol would accumulate at a faster rate in the lenses of cats than in the lenses of dogs. Thus, the higher incidence of diabetic cataracts in dogs, compared with cats, is likely not attributable to a difference in the ratio of NADPH-dependent reductases activity-to-sorbitol dehydrogenase activity. 相似文献