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91.
Nils H. Flores Huarco Susana M. Giuliano Fernanda G. Fumuso Marcelo H. Miragaya Hernán C. Cucho Dolmos María I. Carretero 《Reproduction in domestic animals》2021,56(11):1387-1397
The objective of this study was to evaluate the effect of collagenase and two final dimethylformamide (DMF) concentrations (4% and 7%) on alpaca frozen-thawed sperm quality. A total of 25 ejaculates from 5 alpaca were obtained using electroejaculation. Each individual ejaculate was evaluated and then diluted 4:1 in a solution of 1 mg/ml collagenase in HEPES-TALP medium and incubated for 4 min at 37°C. Subsequently, samples were diluted in TRIS-fructose-citric acid-egg yolk and cooled to 5°C. Then, each sample was divided in two aliquots and DMF at final concentration of 4% or 7% was added, equilibrated for 1 hr at 5°C and frozen over liquid nitrogen vapours. A Kruskal–Wallis test was used to evaluate the sperm morphometry, and Completely Random Block designs were used to analyse sperm motility, viability, membrane function and acrosome status. After collagenase incubation, none of the samples showed thread formation, and sperm parameters were preserved. Non-progressive motile sperm were higher (p < .05) in equilibrated samples (4% DMF: 31.8 ± 8.3% and 7% DMF: 36.3 ± 11.8%) compared to raw (10.1 ± 4.3%) and frozen-thawed semen (4% DMF: 9.7 ± 1.8% and 7% DMF: 7.5 ± 3.2%). Sperm membrane function, membrane integrity and intact acrosomes were higher (p < .05) in raw semen (40.1 ± 12.2%, 94.6 ± 3.2% and 91.3 ± 8.1%) compared to frozen-thawed samples (4% DMF: 19.8 ± 4.7%, 53.2 ± 2.7%, 65.7 ± 8.7% and 7% DMF: 20.4 ± 4.5%, 54.1 ± 1.4%, 64.6 ± 9.1%). Length of the sperm head was lower in frozen-thawed samples, being statistically different with 4% DMF compared to pre-freezing samples. The ratio between acrosome and head areas was greater (p < .05) in frozen-thawed samples. Incubation of raw alpaca semen with collagenase decreased the thread formation without affecting sperm quality. Frozen of collagenase treated alpaca semen with 4% or 7% DMF did not preserve the sperm parameters in thawed samples. 相似文献
92.
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
93.
M. Muoz‐Rojas A. Jordn L. M. Zavala D. De la Rosa S. K. Abd‐Elmabod M. Anaya‐Romero 《Land Degradation \u0026amp; Development》2015,26(2):168-179
During the last few decades, land use changes have largely affected the global warming process through emissions of CO2. However, C sequestration in terrestrial ecosystems could contribute to the decrease of atmospheric CO2 rates. Although Mediterranean areas show a high potential for C sequestration, only a few studies have been carried out in these systems. In this study, we propose a methodology to assess the impact of land use and land cover change dynamics on soil organic C stocks at different depths. Soil C sequestration rates are provided for different land cover changes and soil types in Andalusia (southern Spain). Our research is based on the analysis of detailed soil databases containing data from 1357 soil profiles, the Soil Map of Andalusia and the Land Use and Land Cover Map of Andalusia. Land use and land cover changes between 1956 and 2007 implied soil organic C losses in all soil groups, resulting in a total loss of 16·8 Tg (approximately 0·33 Tg y−1). Afforestation increased soil organic C mostly in the topsoil, and forest contributed to sequestration of 8·62 Mg ha−1 of soil organic C (25·4 per cent). Deforestation processes implied important C losses, particularly in Cambisols, Luvisols and Vertisols. The information generated in this study will be a useful basis for designing management strategies for stabilizing the increasing atmospheric CO2 concentrations by preservation of C stocks and C sequestration. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
94.
David Santiago‐Ramos Juan de Dios Figueroa‐Crdenas Jos Juan Vles‐Medina Rosalía Reynoso‐Camacho Minerva Ramos‐Gmez Marcela Gaytn‐Martínez Eduardo Morales‐Snchez 《Cereal Chemistry》2015,92(5):475-480
The objective of the present work was to study the effect of annealing and concentration of Ca(OH)2 (lime) and calcium salts on the thermal and rheological properties of maize starch during an ecological nixtamalization process. Thermal and rheological properties of maize starch changed during the ecological nixtamalization process because of three main causes: the annealing phenomenon, type of calcium salt, and calcium salt concentration. In all treatments thermal properties (To, Tp, and Tf) of nixtamal starch increased owing to the annealing process, whereas the type of salt or lime increased thermal properties and decreased pasting properties in this order: CaCl2 > CaSO4 > Ca(OH)2 ≈ CaCO3. This behavior was because of the dissociation of each salt or lime in water. Anions (OH−) can penetrate much more easily into the starch granule and start the gelatinization process by rupturing hydrogen bonds. Additionally, amylose‐lipid complexes were formed during the nixtamalization processes, as indicated by an increasing peak at 4.5 Å in X‐ray diffraction patterns. 相似文献
95.
96.
TECHNIQUE,DIFFICULTY, AND ACCURACY OF COMPUTED TOMOGRAPHY‐GUIDED TRANSLAMINAR AND TRANSFORAMINAL LUMBOSACRAL EPIDURAL AND INTRAARTICULAR LUMBAR FACET JOINT INJECTIONS IN DOGS 下载免费PDF全文
Annalisa Liotta Charlotte Sandersen Thierry Couvreur Géraldine Bolen 《Veterinary radiology & ultrasound》2016,57(2):191-198
In human medicine, spinal pain and radiculopathy are commonly managed by computed tomography (CT)‐guided facet joint injections and by transforaminal or translaminar epidural injections. In dogs, CT‐guided lumbosacral epidural or lumbar facet joint injections have not been described. The aim of this experimental, ex vivo, feasibility study was to develop techniques and to assess their difficulty and accuracy. Two canine cadavers were used to establish the techniques and eight cadavers to assess difficulty and accuracy. Contrast medium was injected and a CT scan was performed after each injection. Accuracy was assessed according to epidural or joint space contrast opacification. Difficulty was classified as easy, moderately difficult, or difficult, based on the number of CT scans needed to guide insertion of the needle. A total of six translaminar and five transforaminal epidural and 53 joint injections were performed. Translaminar injections had a high success rate (100%), were highly accurate (75%), and easy to perform (100%). Transforaminal injections had an moderately high success rate (75%), were accurate (75%), and moderately difficult to perform (100%). Success rate of facet joint injections was 62% and was higher for larger facet joints, such as L7‐S1. Accuracy of facet joint injections ranged from accurate (37–62%) to highly accurate (25%) depending on the volume injected. In 77% of cases, injections were moderately difficult to perform. Possible complications of epidural and facet joint injections were subarachnoid and vertebral venous plexus puncture and periarticular spread, respectively. Further studies are suggested to evaluate in vivo feasibility and safety of these techniques. 相似文献
97.
Andrea Weissman Mauricio Solano Olivier Taeymans Shannon P. Holmes David Jiménez Bruce Barton 《Veterinary radiology & ultrasound》2016,57(2):124-129
An imaging report is a vital communication tool between a radiologist and clinician. In a field where in‐person communication may not be readily available, it is imperative that the report clearly relays pertinent clinical information in a timely manner. The purpose of this observational study was to describe and compare opinions and expectations of small animal general practitioners, veterinary specialists, and veterinary radiologists regarding the imaging report. Online surveys were distributed, and data were collected from 202 veterinary clinicians and 123 veterinary radiologists. The majority (89%) of clinicians were satisfied with their imaging reports and stated that they read the radiology report as soon as it was available (92%). Just less than half (48%) of clinicians indicated it was standard of care that a board‐certified veterinary radiologist read all imaging studies. Radiologists and clinicians agreed that a clinical history (98% and 94%, respectively) and clinical question (82% and 68%, respectively) were needed to generate a good radiology report. Fifty‐five percent to 70% of clinicians prefer red bulleted reports, which included incidental findings (96%); while radiologists slightly favored prose reporting (37–46%). Clinicians found it helpful when additional imaging (86%), medical (71%), and surgical recommendations (73%) were made. About one‐third of specialists who had been in practice for >11 years thought they were better able to interpret imaging for their own specialty than the radiologist. Clinicians voiced discontentment with reports that were not completed in a timely manner or did not give a prioritized differential list. Further studies are warranted to provide a more in‐depth evaluation of veterinary radiology reporting structure and style. 相似文献
98.
99.
100.
The African Penguin (Spheniscus demersus) has suffered population declines and is listed in the IUCN Red List as Endangered. The species is endemic to the coast of southern Africa, and breeding colonies are distributed on the south-western coast of Africa. Currently, African Penguins are being kept in zoo and aquarium facilities throughout South Africa. In this study, molecular genetic data based on 12 microsatellite markers from 1 119 African Penguin samples from four facilities were generated in order to determine the level of genetic variation, population structure and differentiation, and effective population size to assist in the development of an effective captive management plan. Expected heterozygosity ranged from 0.57 to 0.62, and allelic richness from 4.2 to 5.1. However, based on differences between first- and second-generation captive birds, we conclude that the ex situ population is at risk of losing genetic variability in the future and management programmes should include exchange of birds between captive facilities in order to induce gene flow and increase effective population size. Adding individuals from in situ populations should also be considered in the future in cases where these birds cannot be rehabilitated. Molecular genetic analyses of wild penguin populations should be carried out for comparison, and to ascertain to what degree ‘in situ genetic diversity’ is represented among ex situ populations. With regular resampling and analyses, the extent of the effect of processes such as genetic drift on diversity in the ex situ penguin populations will become evident. 相似文献