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61.
Magdalena Zielinska Piotr Zapotoczny Ireneusz Białobrzewski Krystyna Zuk-Golaszewska Marek Markowski 《Industrial Crops and Products》2012,37(1):69-75
Selected engineering properties of seeds of four red clover varieties were studied. The seeds of diploid and tetraploid forms were statistically different in terms of true and bulk density, porosity, volume, 1000 seed weight, equivalent diameter and yellowness index. The volume, 1000 seed weight and equivalent diameter were found to be statistically higher for tetraploid than for diploid forms. The accuracy of varietal classification based on the physical properties of seeds was found to be most satisfactory. Varieties of Bona and Jubilatka were identified with 100% accuracy based on the physical properties of seeds. Bona was the most conducive variety for the classification of red clover seeds based on four groups of engineering properties. The relationships between groups of properties described by total redundancy did not exceed 50% for any of variable pairs. 相似文献
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David Hlaváč Maria Anton-Pardo Jan Másílko Pavel Hartman Ján Regenda Pavel Vejsada Marek Baxa Libor Pechar Olga Valentová Lucie Všetičková Bořek Drozd Zdeněk Adámek 《Aquaculture International》2016,24(6):1681-1697
To test the influence of supplementary feeding with thermally treated cereals on nutrient budget and environmental and biotic variables, three different treatments were applied in four experimental ponds: two with thermally treated cereals, one with raw cereal and a control with no supplementary feeding. Water parameters, zooplankton and zoobenthos were analysed from May to October over two consecutive years (2012 and 2013). In addition, nitrogen and phosphorus budgets were calculated as the difference between input (feed, stocked fish) and output (harvested fish). The results showed that type of supplementary feed had no influence on water quality, aside from water transparency. Ponds with added thermally treated cereal had significantly (P < 0.05) lower turbidity and suspended solids (and increased Secchi depth) compared with control. While no significant differences were observed in zooplankton assemblages between the experimental ponds and the control, macrozoobenthos density and biomass were considerably lower in the control pond. High seasonal fluctuations resulted in significant differences in density in 2012 only. The use of thermally treated cereal led to improved carp growth and nutrient budget, with an increase in carp yield and nutrient removal per hectare of pond surface. This result is a win–win situation with 10 % lower feed conversion ratio, increased profits and lower environmental impact. 相似文献
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Birth in all higher vertebrates is at the center of the critical window of development in which newborns transition from dependence on innate immunity to dependence on their own adaptive immunity, with passive maternal immunity bridging this transition. Therefore we have studied immunological development through fetal and early neonatal life. In swine, B cells appear earlier in fetal development than T cells. B cell development begins in the yolk sac at the 20th day of gestation (DG20), progresses to fetal liver at DG30 and after DG45 continues in bone marrow. The first wave of developing T cells is gammadelta cells expressing a monomorphic Vdelta rearrangement. Thereafter, alphabeta T cells predominate and at birth, at least 19 TRBV subgroups are expressed, 17 of which appear highly homologous with those in humans. In contrast to the T cell repertoire and unlike humans and mice, the porcine pre-immune VH (IGHV-D-J) repertoire is highly restricted, depending primarily on CDR3 for diversity. The V-KAPPA (IGKV-J) repertoire and apparently also the V-LAMBDA (IGLV-J) repertoire, are also restricted. Diversification of the pre-immune B cell repertoire of swine and the ability to respond to both T-dependent and T-independent antigen depends on colonization of the gut after birth in which colonizing bacteria stimulate with Toll-like receptor ligands, especially bacterial DNA. This may explain the link between repertoire diversification and the anatomical location of primary lymphoid tissue like the ileal Peyers patches. Improper development of adaptive immunity can be caused by infectious agents like the porcine reproductive and respiratory syndrome virus that causes immune dysregulation resulting in immunological injury and autoimmunity. 相似文献
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Summary The principle of operation of a simple, manually controlled Time Domain Reflectometer (TDR meter) for soil moisture measurements, which operates with a needle pulse of 300 ps rise-time, is described. A block diagram and constructions are also given. Construction of a switchless multiple sensor probe, having an inherent delay reference, is presented. Results of measurements of the soil dielectric constant as related to water content, for soils having different bulk densities, textures and humus content show a high correlation. The results agree closely with other investigators measurements with different, more expensive, TDR instruments. The general principle of microprocessor-controlled TDR operated soil moisture meter is considered.Patent pending 相似文献
66.
Opalka M Kugla-Owczarska J Kaminska B Puchajda-Skowronska H Hryniewicka W Dusza L 《Acta veterinaria Hungarica》2008,56(3):379-391
The aim of this study was to investigate how long-term feeding of ganders with diets containing different levels of phytoestrogens affects the morphometry of testes, plasma steroid levels, sperm parameters and reproductive performance. Male Bilgoraj geese were fed diets containing grass meal (with low phytoestrogen levels) and those containing alfalfa meal and soybean meal (with higher levels of phytoestrogens). Testes were obtained from ganders at the peak of mating and the ongoing laying period as well as at the beginning of photorefractoriness. The morphometric parameters were measured in frozen testicular sections. Blood was collected monthly from December to June, and plasma testosterone, androstenedione and corticosterone concentrations were determined. During the mating season, semen was collected and its quantity and quality were investigated. In the flocks (ganders with geese) reproductive output was noted. Seasonal changes were observed in the morphology of testes and in plasma testosterone, androstenedione and corticosterone concentrations in ganders. The feeding of ganders with dietary meals containing higher levels of phytoestrogens did not affect the plasma steroid contents or the majority of the morphometric parameters of testes, except for the height of the seminiferous epithelium, which was lowered. Moreover, diets with higher levels of phytoestrogens decreased the volume of ejaculates and the percentage of normal spermatozoa. However, these changes were not reflected in the fertilisation rates. 相似文献
67.
Interactions between fawns and does of farmed fallow deer Dama dama in the postnatal period 下载免费PDF全文
Paweł Janiszewski Justyna Cilulko‐Dołęga Daria Murawska Marek Bogdaszewski 《Animal Science Journal》2018,89(2):483-487
The aim of the present study was to describe the suckling behavior of the offspring of farmed European fallow deer Dama dama in the postnatal period. Video surveillance footage from the first 18 days postpartum was analyzed in detail to reveal that the duration of interactions between the mother and the offspring changed with the fawns’ age. The duration of mother‐offspring interactions was longest between postpartum days 12 and 18. The frequency of interactions at different times of the day varied in the analyzed periods. The results of the study could be used to increase the welfare of farmed deer. 相似文献
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Early detection of neurodegenerative disorders would provide clues to the underlying pathobiology of these diseases and would enable more effective diagnosis and treatment of patients. Recent advances in molecular neuroscience have begun to provide the tools to detect diseases like Alzheimer's disease, Parkinson's disease, and others early in their course and potentially even before the development of clinical manifestations of disease. These genetic, imaging, clinical, and biochemical tools are being validated in a number of studies. Early detection of these slowly progressive diseases offers the promise of presymptomatic diagnosis and, ultimately, of disease-modifying medications for use early in disease and during the presymptomatic period. 相似文献