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21.
K. De Keyser S. Janssens L.M. Peeters N. Foqué F. Gasthuys M. Oosterlinck N. Buys 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2014,131(6):522-528
Genetic parameters for chronic progressive lymphedema (CPL)‐associated traits in Belgian Draught Horses were estimated, using a multitrait animal model. Clinical scores of CPL in the four limbs/horse (CPLclin), skinfold thickness and hair samples (hair diameter) were studied. Due to CPLclin uncertainty in younger horses (progressive CPL character), a restricted data set (D_3+) was formed, excluding records from horses under 3 years from the complete data set (D_full). Age, gender, coat colour and limb hair pigmentation were included as fixed, permanent environment and date of recording as random effects. Higher CPLclin certainty (D_3+) increased heritability coefficients of, and genetic correlations between traits, with CPLclin heritabilities (SE) for the respective data sets: 0.11 (0.06) and 0.26 (0.05). A large proportion of the CPLclin variance was attributed to the permanent environmental effect in D_full, but less in D_3+. Date of recording explained a proportion of variance from 0.09 ± 0.03 to 0.61 ± 0.08. Additive genetic correlations between CPLclin and both skinfold thickness and hair diameter showed the latter two traits cannot be used as a direct diagnostic aid for CPL. Due to the relatively low heritability of CPLclin, selection should focus on estimated breeding values (from repeated clinical examinations) to reduce CPL occurrence in the Belgian Draught Horse. 相似文献
22.
Chantal A.P.M. Verboven Sylvia C. Djajadiningrat‐Laanen Willem‐Jan P. Kitslaar Guy C.M. Grinwis Nico J. Schoemaker Michael H. Boevé 《Veterinary ophthalmology》2014,17(4):290-293
A 4‐year‐old intact male ferret was presented to the Ophthalmology Service of the Department of Clinical Sciences of Companion Animals of Utrecht University with chronic blepharospasm, epiphora, and conjunctivitis of the right eye. Examination of the eye revealed mild conjunctivitis and three hairs protruding from the openings of meibomian glands in the upper eyelid, providing the clinical diagnosis of distichiasis. The distichia were removed by transconjunctival unipolar electrocautery. Recovery was uneventful, but the original signs recurred 10 weeks after surgery. Ophthalmic examination revealed another distichia at a different location in the same eyelid and it was removed by full‐thickness wedge excision. Histopathological examination failed to reveal the exact origin of the distichia. To our knowledge, this is the first reported case of distichiasis in a ferret. 相似文献
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24.
《Communications in Soil Science and Plant Analysis》2012,43(7-8):1103-1110
Abstract Signal molecules are among the major factors required for the legume–bacteria symbiosis. The excretion of signal molecules by plants stimulates the bacterial Nod genes resulting in the production of lipochitooligosacharides (LCOs). LCOs cause root hair deformation (RHD) and induction of nodule cells division, leading to the formation of nodules. The chemical structure of LCOs determines their biochemical activities; for example, removal of the sulfate group can significantly reduce the morphogenic activities of LCOs. Stressful conditions interrupt the excretion of signal molecules by the legumes' roots and consequently the inhibition of LCO production by the bacteria. This research has studied the effect of different concentrations of LCOs on RHD of two soybean [Glycine max (L.) Merr] cultivars, AC Bravour and Maple Glen, under acidity stress. In the first experiment, two different concentrations of LCO (10?7 and 10?6M) and in the second experiment, three different concentrations of LCO (10?7, 10?6, and 10?5M) were added to the soybean roots subjected to the pH levels of 4, 5, 6, and 7 for 24 h. By microscopy observation, the ratios of RHD were determined. Addition of LCOs resulted in RHD in both cultivars. Maple Glen roots responded similarly to different concentrations of LCO, whereas roots of AC Bravour responded differently. The concentration of 10?5M LCO could inhibit the stressful effect of pH 4 on RHD compared with pH 7 in both cultivars. The significant interaction between LCO and pH suggests that the effect of LCO on RHD may be more significant under higher levels of acidity. 相似文献
25.
R. M. M. S. Thilakarathna Y. A. Papadopoulos S. A. E. Fillmore B. Prithiviraj 《Journal of Agronomy and Crop Science》2012,198(4):295-303
Red clover cultivars, including diploid and tetraploid, are commonly used in legume‐based pasture mixtures. However, information on nodulation under different starter N regimens is limited. We hypothesized that there is genetic variability among different red clover cultivars for nodulation. A root hair deformation assay was conducted using three diploid (AC Christie, Tapani and CRS15) and three tetraploid (Tempus, CRS18 and CRS39) red clover cultivars by inoculating them with Rhizobium leguminosarum biovar trifolii. Nodulation and morphological characteristics of two selected red clover cultivars, AC Christie and Tempus, were determined under five starter N concentrations (0, 0.2, 0.4, 0.8 and 1.6 mg per plant). Inoculation with rhizobia increased root hair deformation with significant interaction across cultivars. Nodulation was delayed under high starter N concentrations, and genotypic differences were evident for days‐to‐nodule initiation. There was a positive quadratic response to starter N for AC Christie and a negative quadratic response for Tempus for nodulation. Tempus had more active nodules (92 %) than AC Christie (73 %). The genetic variability of red clover cultivars should be considered in N fixation studies and their response to availability of initial N. 相似文献
26.
本文对当前众多养猪户在猪品种毛色与性能、仔猪早期断奶、育肥猪的合圈饲养与配合饲料的使用方面存在的认识偏差产生原因和克服方法从技术上进行了讨论 ,这些偏差已在一定程度上制约了养猪生产的发展。建议通过加大宣传、教育、引导和科学技术普及力度 ,提高认识 ,以提高养猪生产水平的经济效益 相似文献
27.
D. M. De Costa R. M. P. S. Rathnayake W. A. J. M. De Costa W. M. D. Kumari D. M. N. Dissanayake 《Journal of Agronomy and Crop Science》2006,192(3):209-220
Anatomical and physiological characters of the leaf surface and its physico‐chemical environment substantially influence the density and diversity of phyllosphere‐inhabiting microorganisms, which may include natural antagonists of important pathogens. The objective of this investigation was to quantify the phyllosphere (i.e. leaf surface) microbial population in a range of rice varieties grown in Sri Lanka and to identify the leaf anatomical and physiological characters that determine the density and diversity of phyllosphere microbes. Fifteen rice varieties including both traditional and new high‐yielding varieties were used in a planthouse experiment and a field experiment in two consecutive seasons to quantify the phyllosphere microbial population and measure leaf characters that may influence it. There were highly significant intervarietal variations in the density and diversity of epiphytic bacterial, fungal and total microbial populations under both planthouse and field conditions. However, there was no difference between traditional and new, high‐yielding varieties in their capacity to harbour epiphytic microbes in the phyllosphere. Total microbial density (TMD) under both conditions showed positive correlations with leaf hair density, stomatal density and transpiration rate. Under planthouse conditions, TMD was also positively correlated with leaf hair length and negatively correlated with leaf temperature. These correlations can be explained in terms of providing favourable microsites on the phylloplane for epiphytic microbial growth. 相似文献
28.
动物毛发的形态结构及其功能特性研究 总被引:10,自引:0,他引:10
对人发及其他14种动物毛发的扫描电镜(SEM)照片进行分析,根据它们形态结构特征将其分为指状结构、芽状结构、鳞状结构和波状结构4类,并就每种毛发结构的保温性、疏水性及其柔性进行了比较分析。分析结果表明,具有指状细观结构形态的毛发在保温性、疏水性及柔韧性方面具有明显优势,这一信息对研究开发新型功能材料具有借鉴作用 相似文献
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30.
杨瑞林 《山西农业大学学报(自然科学版)》2002,22(1):11-13
对几种指定纤维进行了扫描电镜 (SEM)观察 ,并且利用X射线能谱仪 (EDX)分别对兽毛的鳞片层、髓质层和化学纤维进行了元素分析 ,建立了不同纤维的比较研究方法 ,具有定性准确、分辨率高、特征信息明显之特点 ,已用于商检和物证鉴定中。 相似文献