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101.
Detection of equine X chromosome mosaicism in a mare using an equine X whole chromosome painting probe (WCPP)--a case report 总被引:1,自引:0,他引:1
An infertile mare with hypoplastic ovaries was subjected to cytogenetic analysis. Fluorescence in situ hybridisation (FISH) using the equine X whole chromosome painting probe (WCPP) was carried out on a chromosome preparation obtained from blood lymphocyte culture. The number of analysed spreads was high (235) and in the X chromosome aneuploidy in mosaic form was diagnosed. The karyotype formula was 63,X / 64,XX / 65,XXX. The ratio of the three lines was 15%, 82% and 3%, respectively. The application of the FISH technique with WCPP is discussed. 相似文献
102.
It is common knowledge that fish are a nutritious component of a human diet, as they constitute a valuable and desired source of protein and polyunsaturated fatty acids. However, they are likely to pose a risk to consumer health. The presence of pathogenic bacteria or their toxins, parasites, biogenic amines and toxins or chemical residues may be a causal agent of foodborne illnesses in humans, sometimes even with fatal effect. Usually, infections are a result of insufficient thermal treatment or consumption of raw fish dishes. There are also risk factors that cannot be eliminated by such treatments as cooking, salting or freezing. 相似文献
103.
M. Kozioł 《Journal of pest science》1998,71(7):121-127
A field study onKaltenbachiola strobi (Winnertz) (Diptera: Cecidomyiidae), was carried out between 1987 and 1993 in the highest mountain range in the Western Carpathians
located within the Tatra National Park, in southern Poland. Rearing and analysis of 5 780 cones ofPicea abies (L.)Karst., collected from trees growing at different altitudes, yielded 30,478 individuals ofKaltenbachiola strobi, which infested 89.10% of the cones. In case of 29.81% of cones there were more than 20 larvae ofK. strobi per cone. It was shown thatK. strobi in the Tatra Mts. is more abundant in spruce stands of the upper mountain forest zone. Significant connections between the
time of cone infestation byK. strobi and its parasitoids and characteristic phenophases in spruce foliage and cone development, and also the development of selected
vegetation of the forest floor at different heights above sea level were determined. It was shown that the population dynamics
ofK. strobi had tendency to alternate the increase and decrease in numbers every two years. It was also discovered that every two years
spruce cones were inhabited by the population ofK. strobi with increased percentage of individuals having prolonged diapause. In total, the parasitoids reduced the population ofK. strobi by about 16–22.63%. Parasitism ofK. strobi in the lower mountain forest zone was higher than in the upper zone.Triplatygaster contorticornis
Ratz. (Hymenoptera: Platygasteridae),Torymus azureus
Boheman (Hymenoptera: Torymidae) andTetrastichus strobilanae
Ratz. (Hymenoptera: Eulophidae) were most effiecient in reduction of the population ofK. strobi, and in the lower mountain forest zoneT. azureus was the dominant parasitoid species, while in the upper zoneT. contorticornis andT. strobilanae. It was shown that a considerable part of the populations ofT. azureus, T. contorticornis andT. strobilanae have their diapause prolonged and highly synchronized with the diapause of their host. 相似文献
104.
105.
Janusz Kloskowski Andy J. Green Marcin Polak Javier Bustamante Jarosław Krogulec 《水产资源保护:海洋与淡水生态系统》2009,19(7):815-826
- 1. The Doñana wetland complex (SW Spain) holds more wintering waterfowl than any other wetland in Europe.
- 2. This study focused on the use made by 12 common waterbirds (eight ducks and four waders) of the natural seasonal marshes in Doñana National Park (DNP) and the adjacent Veta la Palma (VLP) fish ponds created in the early 1990s. Data used were from aerial and terrestrial surveys collected between October and February during six consecutive winters from 1998/99 to 2003/04. Changes in distribution of each bird taxon were related to changes in the extent of flooded marshes within DNP. Up to 295 000 ducks were counted in VLP during dry periods, and up to 770 000 in DNP when it was flooded.
- 3. The timing and extent of flooding in DNP was highly variable, but there was a consistent pattern in which ducks concentrated in VLP during dry months and winters but redistributed to DNP as more of it was flooded. This refuge effect was also strong for black‐tailed godwits Limosa limosa, but much less so for other waders. Waders feed mainly on invertebrates, and invertebrate biomass in VLP was found to be higher than in DNP. Ducks feed mainly on seeds and plant material, which are more abundant in DNP when flooded.
- 4. When water levels in DNP were stable over the course of a winter, or controlled for in multivariate models, the numbers of ducks at VLP declined over time, probably due to reduced availability of plant foods. In contrast, numbers of waders at VLP were more stable, and their invertebrate prey became more abundant over time, at least in the winter 2003/4.
- 5. In this extremely important wetland complex, the value of natural and artificial wetlands for wintering waterbirds are complementary, providing suitable habitat for different species and for different conditions in a highly variable Mediterranean environment.
106.
Combined effects of water temperature and daily food availability period on the growth and survival of tench (Tinca tinca) larvae 下载免费PDF全文
A 16‐day experiment was designed to find the best combination of water temperature (27, 30, 33°C) and daily duration of food availability (12, 18, 24 h) for larval tench (Tinca tinca) growth and survival. Larvae with an initial mean size of 5.7 mm total length (TL) and 0.7 mg wet body weight (BW) were stocked at 15 L?1. Larvae were fed in excess with live Artemia nauplii with the period of food availability lasting 12, 18 or 24 h daily. The largest final larval size was recorded at 27 and 30°C in groups fed for 24 h a day (17.7 and 17.9 mm TL, 76.1 and 77.7 mg BW, respectively). The combination of the highest temperature and the longest daily food availability was the only set of conditions under which final larval survival was affected (95.4% survival; 98.7–99.9% under all other conditions). The combination of water temperature of about 28.6°C and continuous food availability is recommended as the optimum combination for rearing T. tinca larvae under controlled conditions. Providing continuous food supply to fish larvae under aquaculture conditions was also advantageous in helping to mitigate the effects of slower growth relative to developmental progress, which can occur at high water temperatures. However, should one wish to limit the daily feeding period to 12 h per day, the use of a water temperature between 27.4 and 27.9°C would be the best solution. 相似文献
107.
108.
Wies?aw Szulczewski Ma?gorzata Biniak-Pieróg Anna Machowczyk 《Agricultural Water Management》2010,97(5):587-595
The paper presents a weather-yield model developed for the purpose of estimating spring barley yield on the basis of dry spells occurring in individual periods between the phenological phases of that plant. For that purpose research material on spring barley, originating from the years 1976-1997, was used as well as diurnal sums of precipitation. Five periods were considered in the analysis: sowing-emergence, emergence-tillering, tillering-heading, heading-milk ripeness and milk ripeness-full ripeness. In the study a model of changes in the amount of water available for plant during rainless periods was used. Five measures were adopted for characterisation of the approximation error: correlation coefficient, mean relative error, relative root mean square error, model efficiency and coefficient of residual mass. The analyses performed demonstrated that yield reduction is significantly influenced by rainless periods that occur in the sowing-emergence and tillering-heading inter-phase periods. The adopted criteria for yield reduction estimation show considerable similarity for the emergence-tillering and heading-milk ripeness inter-phase periods. At the same time, their influence on yield reduction is three-fold lower than during the sowing-emergence and tillering-heading inter-phase periods. Analyses performed with the use of the developed model indicate that yield size is affected by rainless periods of duration longer than 30% of the inter-phase period. 相似文献
109.
The study was conducted in the years from 2011 to 2013 at the Research Institute of Horticulture in Skierniewice, Poland. The aim of the research was to assess the breeding value, based on the effects of general and specific combining abilities (GCA and SCA), of 15 parental genotypes of blackcurrant in terms of fruit yield and quality. The plant material consisted of F1 generation seedlings obtained by crossing, in a factorial mating design of twelve maternal (‘Bona’, ‘Big Ben’, ‘Chereshnieva’, Kupoliniai’, ‘Gofert’, ‘Tines’, ‘Sofievskaia’, ‘Tihope’, ‘Ores’, ‘Ruben’, ‘Titania’ and D13B/11) and three paternal cultivars (‘Ceres’, ‘Foxendown’ and ‘Saniuta’). It was found that the cultivars ‘Ruben’, ‘Big Ben’, ‘Gofert’ and D13B/11 had significant positive effects of GCA on fruit yield at least in two consecutive years. ‘Ruben’, ‘Saniuta’ and D13B/11 had positive GCA effects on fruit weight. For ‘Chereshnieva’, ‘Gofert’, ‘Tines’, ‘Sofievskaia’, ‘Tihope’, ‘Titania’, ‘Ceres’ and Saniuta’ positive GCA effects were estimated for soluble solids content, whereas ‘Ruben’, ‘Ceres’, ‘Gofert’ and ‘Ores’ had positive GCA effects on the ascorbic acid content in fruit. This indicated a high breeding value of these parental genotypes in terms of the evaluated traits. The significantly positive values of SCA, estimated for the crossing combinations: ‘Big Ben’?×?‘Saniuta’, ‘Ruben’?×?‘Foxendown’, ‘Titania’?×?‘Ceres’, ‘Kupoliniai’?×?‘Saniuta’, ‘Gofert’?×?‘Foxendown’, ‘Gofert’?×?‘Saniuta’, ‘Tines’?×?‘Ceres’ and ‘Tihope’?×?‘Foxendown’ for at least two traits describing fruit yield and quality, were evidence of the interaction of both these parental genotypes in the creation of new dessert-type cultivars of blackcurrant. 相似文献
110.
Piotr Hulisz Przemysław Charzyński Andrzej Greinert 《Journal of Soils and Sediments》2018,18(2):358-372