共查询到19条相似文献，搜索用时 101 毫秒
1.
清远麻鸡蛋品质研究 总被引：1，自引：0，他引：1
文章对40周龄清远麻鸡蛋品质进行了研究,结果表明:清远麻鸡平均蛋重46.59 g,蛋形指数1.36,比重1.082,蛋壳强度2.67 kg/cm2,蛋壳厚度362.22μm,哈氏单位64.94,蛋黄色泽(级)7.96,蛋黄比率35.24%。蛋壳平均气孔密度115.13个/cm2,钝端显著高于中部和锐端(P0.01),不同气孔的面积差异很大,55.66%的气孔面积在10 000μm2以下,平均为16 844.25μm2/个,变异系数达79.67%,具有不同气孔密度的蛋的比例基本属于正态分布。蛋比重、蛋壳强度与蛋壳厚度之间呈显著正相关(P0.01)。 相似文献
2.
番鸭蛋壳气孔数、壳厚对出雏效果的研究 总被引：1，自引：0，他引：1
本试验分别测定新鲜番鸭种蛋 ;一照健胚蛋、死胚蛋 ;三照死胚蛋、正常出雏蛋和毛蛋的大端、中部和小端的气孔数及厚度。结果表明 :一照、三照死胚蛋和毛蛋与一照健胚蛋和正常出雏蛋气孔数差异极显著 (P <0 .0 1) ;而三照死胚蛋和毛蛋的蛋壳厚度均极显著高于正常出雏蛋 (P <0 .0 1)。并对新鲜种蛋、毛蛋和正常出雏蛋蛋壳进行扫描电镜观测 ,结果显示蛋壳结构与其它禽蛋相似 ,同时也证实了死胚蛋蛋壳厚度 (0 .395～ 0 .4 0 1mm)极显著高于正常出雏蛋(0 .36 3mm)。 相似文献
3.
白三叶叶片解剖可塑性及其对光强的响应 总被引：5，自引：1，他引：4
探讨不同光照强度下白三叶叶片解剖特征,叶片可塑性及其对光强环境的响应。结果表明:白三叶叶片结构具有一定的可塑性,其中表皮和叶肉的可塑性较大,而中脉则相对较为稳定;在全光照条件下,叶片为阳生叶特征,叶片较厚,上表皮外切向壁平展,气孔密度大,栅栏组织发达,栅栏细胞长柱形,排列紧密,海绵组织较薄,细胞较小,排列疏松,中脉较厚;在弱光照条件下,叶片为阴生叶特征,叶片较薄,上表皮细胞凸透镜状,气孔密度较小,栅栏组织极不发达,栅栏细胞不规则或漏斗形,海绵组织发达,细胞较大,排列紧密,中脉较薄;非参数相关性分析结果表明,上表皮厚度、海绵组织厚度与相对光照强度呈显著负相关,而上表皮气孔密度、栅栏组织厚度、栅栏组织海绵组织厚度比、栅栏细胞长宽比和中脉厚度等性状与相对光照强度呈显著正相关。 相似文献
4.
对57周龄金定鸭蛋(青壳蛋)和麻鸭蛋(白壳蛋)的主要性状进行测定。结果表明:新鲜的青壳蛋和白壳蛋的蛋重分别为80.57g和64.03g,青壳蛋比白壳蛋重;青壳蛋的蛋壳厚度(0.33mm)较白壳蛋(0.32mm)厚,前者蛋壳较坚实;青壳蛋、白壳蛋的蛋型指数分别为1.43和1.40,青壳蛋的蛋型稍大;新鲜青壳蛋的哈夫单位(86.35)与白壳蛋的(88.55)较接近,差异不大,但青壳蛋的蛋黄指数(8.30)较白壳蛋的(10.05)低。从外部品质可以看出青壳蛋的蛋品质比白壳蛋相对高,而其内部营养成分的对比还有待进一步研究。 相似文献
5.
为了研究叶片微结构特征与柑橘溃疡病抗性的关系。选用罗浮金柑、新生系3号椪柑、纽荷尔脐橙及星露比葡萄柚这四个分别被认为是对柑橘溃疡病具有高抗、抗、耐和高感特性的品种,通过涂抹接种法来在实验室验证其抗病性;采用扫描电镜及树脂包埋半薄切片等技术对上述品种的成熟叶片下表皮气孔及叶片显微解剖结构进行观察测量;将健康叶片浸泡在菌液中,采用细菌分离法来观察同样条件下通过气孔进入不同柑橘品种叶片体内的活细菌数。结果：四个品种对溃疡病抗性存在显著差异;不同品种间气孔密度、气孔大小、叶片厚度、栅栏组织厚度、海绵组织厚度、下皮层厚度也存在差异,其中气孔密度差异达到极显著;健康叶片浸泡接种溃疡病后,分离到的单菌落数的顺序依次是星露比葡萄柚>纽荷尔甜橙>新生系3号碰柑>罗浮金柑。因此,气孔密度对柑橘品种抗病性的解释量极高。 相似文献
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蛋壳质量与元素组成、超微结构关系的研究 总被引：3，自引：0，他引：3
为探寻蛋壳质量与元素组成、超微结构的关系,分别用常规方法和X射线能谱仪测定了同日产65枚蛋的蛋壳质量、蛋壳结构属性与蛋壳元素相对含量,并用环境扫描电子显微镜观察蛋壳超微结构.结果表明,不同强度蛋壳元素相对含量差异不显著,而蛋壳乳突层有效厚度和乳突间隙组间差异显著,高强度组乳突层有效厚度和乳突间隙分别比中强组低23.01%(P<0.01)和14.94%(P<0.05)、比低强度组低73.43%(P<0.01)和25.06%(P<0.05).由此得出,蛋壳超微结构致密度直接影响蛋壳质量,而蛋壳元素组成与蛋壳质量间则无显著关联. 相似文献
8.
菊苣航天诱变新品系叶片旱生结构的比较研究 总被引：1，自引：0，他引：1
对15个菊苣空间诱变新品系叶片进行解剖,选取9项抗旱指标,采用单因素分析方法对各品系进行两两多重比较,得到各指标的灵敏度,以下表皮气孔密度和气孔长度、维管束厚度、叶片厚度4个指标为主进行聚类分析.结果表明不同菊苣新品系叶片的抗旱性解剖结构除表皮厚外差异均达极显著水平.各指标的灵敏度大小依次为:下表皮气孔密度＞下表皮气孔长度＞上表皮气孔长度＞上表皮气孔密度＞维管束＞叶片厚度、叶脉厚度＞下、上表皮厚度.聚类分析结果表明,15个菊苣新品系可聚为3个级别:其中PA-95、PA-96、PA-11、PA-93、PA-49、PA-20、PA-82、PA-42具有较好的抗旱性结构;PA-36、PA-31、PA-57、PA-186、PA-54、PA-26抗旱性结构中等;PA-43的抗旱性结构较差. 相似文献
9.
《家畜生态学报》2021,42(9)
为了探讨饲料对林地散养鸡蛋品质的重要性,本研究选择不同饲粮类型的三个林下养殖场,分别对应全价料型、玉米+麦麸+豆粕型、玉米型,对其鸡蛋物理品质和营养成分进行了测定和对比。研究结果揭示,林地散养模式下,全价料型与玉米+麦麸+豆粕型饲粮的鸡蛋相比,前者的蛋壳质量显著优于后者,蛋壳厚度和强度平均比后者分别高0.03 mm和0.52 kg/cm~2(P0.05)。玉米型饲粮的蛋重、蛋黄重、蛋壳重都极显著低于另外两种饲粮类型,与全价料型相比三项分别低6.33 g、1.17 g和1.22 g(P0.05),此外其蛋壳质量亦是最差的,蛋壳厚度和强度极显著低于全价料型(P0.01)。结果提示,饲粮类型对林地散养鸡蛋品质有非常重要的影响,全价混合饲粮更有助于提升散养鸡蛋的品质。 相似文献
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为探究草地早熟禾叶片表皮特征、解剖结构及光合特性对施氮量的响应特性，本试验以6份草地早熟禾为材料，分别为3份美国引进品种：Merit、Jackrabbit和Park,2份山西本土野生居群：应县和浑源，1份由山西野生居群选育的‘太行草地早熟禾’品系，按照两个施氮水平N1:10 g·m-2(低氮)和N2:40 g·m-2(正常)进行处理，采用徒手切片法和石蜡切片法制片，光学显微镜下拍照并测定叶片上下表皮厚度、细胞长宽比、细胞密度、气孔指数、气孔长宽比、气孔密度，叶片厚度、厚壁组织厚度、维管束面积以及气孔导度和净光合速率等指标。结果表明：N1处理下，草地早熟禾叶片的上下表皮厚度、叶片厚度、厚壁组织厚度、维管束面积、气孔导度和净光合速率显著低于N2处理，而气孔大小与N2处理无显著差异；N2处理下，Jackrabbit和Park的叶片厚度显著高于浑源和应县，其中Park的叶片厚度最大，为173.39μm,Jackrabbi... 相似文献
11.
1. Ultrastructural analyses of the eggshells of one strain of commercial layers indicated that the cuticular layer is rarely present as an even covering over the shell surface and the paired shell membranes are invariably pitted with holes larger than bacterial dimensions. 2. The above conditions pertain irrespective of the age of the laying bird. 3. Bacterial penetration of the eggshell is independent of pore numbers. 4. In the absence of a functional cuticle and with the shell membranes removed, bacteria are checked in their movement by structural modifications in the mammillary layer. 相似文献
12.
Influence of the microstructure on the shell strength of eggs laid by hens of different ages 总被引：7，自引：0，他引：7
1. The eggshell is a bioceramic material constructed of columnar calcite crystals preferentially oriented with their c-axis perpendicular to the shell surface. 2. The influence of microstructure (crystal size, shape and crystallographic orientation of crystal grains) on the mechanical properties of eggshells (shell strength) was investigated using eggs from hens of different ages. 3. There was a strong correlation between crystallographic texture and the strength of the eggshell in the case of eggs laid by young hens. The strength of eggshells increased as the preferential orientation of the crystals constituting the eggshell decreased. 4. By comparing two age populations, the effect of hen age on eggshell properties was evaluated. In general, eggshells from aged hens had a lower breaking strength (less than half that of those laid by young hens) and showed a greater variability in their structural properties such as thickness, grain morphology and crystallographic texture. 5. Texture analysis revealed that shells from eggs laid by aged hens have two preferred crystal orientations, after (001) and (104), compared with mainly one, after (001), in eggs laid by young hens. 6. These observed changes in eggshell properties could be due to changes in the organic matrix of the eggshell associated with ageing of the hens. 相似文献
13.
There are three pigments that affect the color of an eggshell: protoporphyrin, biliverdin and biliverdin‐zinc chelate. Protoporphyrin is the main pigment in brown and light‐brown eggshells, whereas very little protoporphyrin is found in white eggshells. Eggshell protoporphyrin is derived from the heme formation in birds. Coproporphyrinogen III oxidase (CPOX) and ferrochelatase (FECH) represent rate‐limiting enzymes for the heme‐biosynthetic pathway. Breast cancer resistance protein (BCRP), feline leukemia virus receptor (FLVCR), and heme‐responsive gene‐1 (HRG1) serve as primary transporters for both protoporphyrinogen and heme. Finally, four organic anion transporting polypeptide family members (including solute carrier organic anion transporter family, SLCO1C1, SLCO1A2, SLCO1B3 and LOC418189) may affect pigment transport within eggshells. Here we measured gene expression levels in key tissues of egg‐producing hens. We analyzed three different types of hens that generated distinct eggshell colors: white, pink or brown. Our data revealed three ways in which eggshell color was genetically influenced. First, high‐level expression of CPOX generated more protoporphyrinogen and a brown eggshell color. In contrast, high expression of FECH likely converted more protoporphyrinogen into heme, reduced protoporphyrinogen levels within the eggshell and generated a light color. Second, heme transporters also affected eggshell color. High‐level expression of BCRP, HRG1 and FLVCR were associated with brown, white and generally lighter eggshell colors, respectively. Finally, protoporphyrin precipitation also affected eggshell color, as high expression of both SLCO1A2 and SLCO1C1 were associated with brown eggshell color. As such, we have identified seven genes in which expression levels in different tissues were associated with eggshell color. 相似文献
14.
本试验旨在通过腿肌注射孕酮来研究孕酮对蛋壳品质的影响。选取72只40周龄的海兰褐蛋鸡,随机分为6组,每组12只蛋鸡,单笼饲养。对照组注射花生油;处理1在排卵后5 h注射1.00 mg/kg体重(BW)的孕酮;处理2和处理3分别在排卵后5 h和2 h注射0.25 mg/kg BW的孕酮;处理4和处理5分别在排卵后2 h和1 h注射0.15 mg/kg BW的孕酮。处理后第2天上午收集各组所产鸡蛋,测定蛋壳强度和厚度。结果表明:处理1所产蛋均为破壳蛋,处理2含部分破壳蛋和部分蛋壳完好的鸡蛋,处理3、处理4和处理5没有破壳蛋;与对照组相比,处理1和处理2的蛋壳厚度降低(P<0.05),处理4蛋壳强度和厚度增加(P<0.05),处理3和处理5的蛋壳强度和厚度无显著差异;与对照组比,处理1和处理4的蛋壳超微结构差异显著。结果显示,孕酮可以影响蛋壳强度和厚度,改变蛋壳超微结构,其影响程度与剂量和注射时间有关。 相似文献
15.
Stress-induced oviposition delays in laying hens: duration and consequences for eggshell quality 总被引：1，自引：0，他引：1
1. This study investigated relationships between the timing of stress, duration of oviposition delays and consequences for eggshell quality, in 2 experiments with ISA Brown hens. 2. Periods of up to 6 h of environmental stress (relocation from an individual cage to a larger one containing 3 unfamiliar hens), commencing up to 4.5 h before predicted oviposition time, reliably induced oviposition delays. Many hens still retained their egg when stress ended. 3. Ovipositions that occurred during stress were never delayed for more than 3.0 h beyond the expected time. Ovipositions that occurred after the period of stress ended usually did so after <1 h if the delay at the end of stress was less than about 2.4 h. Delays that ended either during stress or <2 h after stress ended were classified as short-term. 4. If an oviposition delay was more than about 2.4 h when stress ended, the egg concerned was usually laid much later, after a delay of 7 to 15 h. Delays that ended >5 h after stress ended were classified as long-term. 5. Eggs delayed long-term were white-banded and the subsequent egg was slab-sided, or occasionally soft-shelled. Short-term delays often caused eggshell dusting with varying amounts of superficial calcification. Hence, duration of oviposition delay affects both the number of abnormal eggshells and the degree of abnormality. 6. The present findings are of potential importance to both the egg industry and breeders, because abnormal eggshells cause downgrading and can impair embryonic development. Also, numbers of abnormal eggshells and degree of abnormality can be used as indicators of environmental stress. 相似文献
16.
1. Scanning electron microscopy was used to assess the relationship between the layers of the eggshell and egg viability. The relative thickness (absolute and %) of the mammillary, palisade, vertical crystal and cuticle layers relative to the total eggshell were measured over a 30-week laying period in 2 broiler breeder lines having different hatchability rates. 2. A significant difference in hatchability of 5.5% between the breeder lines was observed. However, there was no significant difference in either egg viability or fertility between lines. 3. The relative thickness of the individual calcified layers and the cuticle did not differ between lines. Therefore, variations in the thickness of the individual eggshell layers are unlikely to explain the 5.5% difference in hatchability rate between lines. 4. The thickness of the calcified region did not alter as the broiler hen aged. However, the percent contribution of each calcified layer significantly differed over the egg production period. 5. The cuticle was significantly thinner at the beginning and at the end of the laying period compared to 38 weeks of age. 6. No significant correlation was observed between egg viability and the relative thicknesses of the mamillary, palisade or cuticle layers. In contrast, there was a positive relationship between egg viability and the thickness of the vertical crystal layer. 7. The percent contribution of the mammillary and palisade layers was similar in the thinnest and thickest eggshells, suggesting conservation of the proportions of these layers independent of eggshell thickness. 相似文献
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S. E. Solomon 《British poultry science》1999,40(1):5-11
1. Many of the mechanical tests devised to measure shell quality are inadequate because they fail to recognise the complex interaction between the organic and inorganic aspects of the eggshell. 2. Twelve structural modifications have been observed at the level of the mammillary layer and their presence correlated with a variety of environmental stress events. Occurring as they do in the basal layers of the shell, these morphological variants influence its mechanical properties. 3. The organic matrix proteins which complex with the calcium carbonate derive from a variety of sites within the oviduct and vary in their location within the fully formed shell. In vitro mineralisation reveals the significance of these proteins in the crystal growth mechanism. 4. The isolation and identification of the protein moiety in well-structured eggshells is an essential prerequisite to understanding the abnormalities in crystal growth observed in the shells of older birds challenged by disease and other undesirable 'on farm' events. 5. The eggshell is the daily indicator of the bird's harmony with its environment and as such provides a readily accessible and non invasive measure of welfare. The integration of these data with those derived from behavioural and biochemical testing should provide industry with a reliable numerical welfare index. 相似文献
19.
Measuring the eggshell strength of 6 different genetic strains of laying hens: techniques and comparisons 总被引：6，自引：0，他引：6
De Ketelaere B Govaerts T Coucke P Dewil E Visscher J Decuypere E De Baerdemaeker J 《British poultry science》2002,43(2):238-244
1. Eggshell quality was compared in 6 different strains of laying hens. Three strains were commercial; the three others were experimental. 2. Four different variables describing the strength of eggshells were investigated. Three of them were the classical ones eggshell thickness, shell stiffness measured during quasi-static compression and breaking force. Dynamic stiffness, introduced by Coucke (Ph.D. Thesis, KU Leuven, 1998), was the 4th. The fact that this measurement is dynamic could be helpful in genetic selection for eggshell breakage, because forces applied to the egg in practice are dynamic, rather than static. 3. Hisex White hens produce eggs with the strongest eggshell, in terms of all 4 eggshell variables. However, their shell quality in terms of breaking force did not remain constant over the laying period, unlike 4 other strains. 4. All strains showed a decline in quasi-static stiffness over time. 5. The eggshell thickness of three strains showed a decline over time. 6. Dynamic stiffness remained constant or improved in all strain. 7. All variables describing the mechanical eggshell strength gave different information. 相似文献