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121.
Nathalie Chenais Alexandra Depince Pierre-Yves Le Bail Catherine Labbe 《Aquaculture International》2014,22(1):63-76
Domestication is a long-term process during which wild fish are acclimated to farming conditions and hopefully are reproduced over several generations, possibly using selective breeding. Preservation of the genetic diversity of the original population, together with that of the ongoing selection steps, is important for ecological and economical purposes. Cryobanking of reproductive cells is one answer to meet this need. In fish, however, only sperm can be cryopreserved as neither oocytes nor embryos are capable of handling the freeze-thawing stress. In this review, we explore to what extent diploid cells obtained from fin pieces can be used for the preservation of both parental genomes. The main parameters, which should be under control to ensure proper production of fin cells in culture and to enable cryopreservation of the material are described. After cryobanking of such non-reproductive cells, fish can be reconstructed using the nuclear transfer technology whose potentials and difficulties are discussed. The gametes produced by the fish reconstructed after somatic cells nuclear transfer are different to some extent from the gametes obtained after the direct transplantation of primordial germ cell or spermatogonial germ cells into host embryos or larvae. However, in some cases, only somatic cells can be obtained in quantities which would be compatible with strain restoration purposes. From the knowledge available today, it is reasonable to expect that nuclear transfer becomes available for fish reconstruction, even if restricted to high-tech biotechnology facilities. Therefore, cryobanking of fin somatic cells can be farsightedly considered for high-throughput diploid genome conservation. 相似文献
122.
Esther Mabafokeng MOHLAKOLA Chunzhen CHENG Yuling LIN Rongfang GUO Kyaw Thu MIN Yukun CHEN Zhongxiong LAI 《农业科学与技术》2017,18(3)
This study was conducted to determine effects of 2,4-dichlorophenoxy acetic acid (2,4-D) and light on growth of gerbera (Gerbera jamesonii cv.Daxueju) callus.Callus was induced from both petiole and leaf explants of gerbera on Murashige and Skoog medium supplemented with 3% sucrose and various concentrations of 2,4-D and placed under light and dark.Callus induction percentage,callus size and callus fresh and dry weights were efficiently higher when using petiole as explant.MS medium supplemented with 1.5 mg/L 2,4-D showed the highest callus induction percentage of 96.70%.Callus induced under light had larger weight mass.It was indicated that 1.5 mg/L 2,4-D and light could promote growth of gerbera callus from petiole explant. 相似文献
123.
This report describes the clinical presentation, diagnosis, histologic lesions, and outcome of endogenous mycotic endophthalmitis secondary to candiduria in a three‐year‐old female spayed Dachshund. The dog was being treated for Evans syndrome for one month prior to being diagnosed with candiduria and fibrinous uveitis OS. The left eye was enucleated due to secondary glaucoma, and the fungal urinary tract infection was treated successfully. Uveitis developed in the contralateral eye with relapse of the urinary tract infection in the following weeks. The right eye was medically managed until secondary glaucoma developed and was subsequently enucleated. Histopathology of both eyes showed evidence of endophthalmitis with intralesional fungal organisms, consistent with Candida spp. Ocular candidiasis is rare in dogs. To the authors' knowledge, this is the first report of endogenous mycotic endophthalmitis with concurrent candiduria in a dog. 相似文献
124.
Hanene Khemiri João Pimenta António Amorim Pascale Chevret Saïd Nouira Alexandra M Lopes 《African Zoology》2017,52(1):9-20
Three Meriones species inhabit Tunisia, namely M. shawi, M. libycus and M. crassus, but little genetic data exist on these gerbils. We collected Meriones from eight localities in Tunisia, and obtained mitochondrial (cytochrome b) and nuclear (IRBP) gene sequence data for 37 and 13 specimens, respectively, belonging to two species: M. shawi and M. libycus. We also optimised three microsatellite markers previously described in M. unguiculatus to obtain a finer analysis of their genetic diversity and geographic structure, given their wide distribution. Phylogenetic inferences of cyt b and IRBP data for these species, in the context of other gerbillin data, corroborate their taxonomic affinities reported by previous studies. High cyt b haplotype diversity was observed in both species (25 haplotypes in 29 and 27 sequences for M. shawi and M. libycus, respectively) with little geographical structure for M. shawi but three divergent groups in M. libycus. The average microsatellite diversity within each population was high (HO ≥ 0.6, HE ≥ 0.8) with M. libycus populations attaining the highest values. Population differentiation was moderate for several population pairs (Fst ≥ 0.1), the highest being between M. shawi populations. However, genetic distance among populations was not significantly correlated with geographic distance in either M. shawi or M. libycus. Our results contribute to a better characterisation of Tunisian Meriones species, suggesting high geographic structure in mtDNA of M. libycus populations within North Africa. 相似文献
125.
Jorge Durán Alexandra Rodríguez José María Fernández-Palacios Antonio Gallardo 《Annals of Forest Science》2010,67(2):207-207
126.
To incorporate ruffed grouse (Bonasa umbellus) habitat planning in forest management, it is necessary for managers to understand factors contributing to grouse habitat use. Previous studies examining ruffed grouse drumming habitat documented relationships between drumming grouse and broad vegetation categories (e.g., northern hardwoods, young aspen [Populus spp.], oak [Quercus spp.]), but few studies have documented how drumming grouse respond to ecological variations in site conditions of aspen or other vegetation types that might be used. Our objectives were to determine the utility of habitat type classifications in predicting the occurrence of ruffed grouse drumming habitat in the western Upper Peninsula of Michigan, and demonstrate how classifications may be used to understand how forest management may affect ruffed grouse habitat. We used survey routes on state land and conducted drumming surveys during mid-April and early May at 78 points in 2005 and 2006. We recorded the number of drumming males heard at each point, the azimuth to where the grouse was heard, and a qualitative measure of distance to determine in which forest stands grouse were drumming. Using GIS, we determined the specific vegetation type, age class, and habitat type, evaluated habitat suitability, and determined a suitability score for areas in which grouse were drumming. We constructed a logistic regression model that calculated the probability of grouse use of areas for drumming based on vegetation characteristics at used and random locations. Our results indicated that the probability of grouse use of an area for drumming is based on inherent site characteristics (i.e., habitat type) and habitat suitability. The model is useful for planning forest management activities and understanding how grouse may respond to spatial or temporal changes in vegetation through succession or manipulation. 相似文献
127.
Esther Sanyé-Mengual Isabelle Anguelovski Jordi Oliver-Solà Juan Ignacio Montero Joan Rieradevall 《Agriculture and Human Values》2016,33(1):101-120
Urban agriculture (UA) is spreading within the Global North, largely for food production, ranging from household individual gardens to community gardens that boost neighborhood regeneration. Additionally, UA is also being integrated into buildings, such as urban rooftop farming (URF). Some URF experiences succeed in North America both as private and community initiatives. To date, little attention has been paid to how stakeholders perceive UA and URF in the Mediterranean or to the role of food production in these initiatives. This study examines the promotion and inclusion of new forms of UA through the practice of URF and contributes to the nascent literature on the stakeholder and public perceptions of UA. It seeks to understand how those perceptions shape the development of new urban agriculture practices and projects. Barcelona (Spain) was used as a Mediterranean case study where UA and URF projects are growing in popularity. Through semi-structured interviews with 25 core stakeholders, we show that UA is largely perceived as a social activity rather than a food production initiative, because the planning of urban gardens in Barcelona was traditionally done to achieve leisure and other social goals. However, several stakeholders highlighted the potential to increase urban fertility through URF by occupying currently unused spaces. As a result, the positive valuation of URF depends on the conceptualization of UA as a social or food production activity. In turn, such conceptualization shapes barriers and opportunities for the development of URF. While most UA-related stakeholders (e.g., food co-ops, NGOs) preferred soil-based UA, newer stakeholders (e.g., architects) highlighted the economic, social and environmental opportunities of local and efficient food production through innovative URF. 相似文献
128.
Esther Martinez-Palle Maria Herrero 《The Journal of Horticultural Science and Biotechnology》2013,88(6):1117-1122
Pollinator performance was evaluated in a collection of 17 male and 37 female pistachio clones from Cyprus, Greece, Iran, Israel, Syria, Tunisia and USA. Flowering time, pollen quantity and pollen quality were evaluated. The flowering dates of the clones spanned one month and covered the flowering time of the main female cultivars. Pollen quality, evaluated as in vitro pollen germination, was high in all the studied clones, averaging 85 %. However, big differences existed in pollen quantity, measured both as inflorescence density and as pollen per inflorescence. Thus, the amount of pollen per inflorescence averaged 173 mg and ranged from 73 mg to 252 mg. The fact that flowering time and pollen quantity were the two most variable characters between clones, but were constant over years, together with the fact that they are two characteristics easily measured in the nursery makes them good criteria for pollinator selection in this species. 相似文献
129.
Ostezan Alexandra McDonald Samuel Clay Tran Dung Thuy Souza Renan Silva E Li Zenglu 《Journal of Crop Science and Biotechnology》2021,24(1):13-26
Journal of Crop Science and Biotechnology - Fine mapping quantitative trait loci (QTL) and understanding the molecular mechanism and underlying functions of genes are vital to the advancement of... 相似文献