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本实验以莆田黑鸭为素材,从羽色及蛋品质的角度对其进行种质特性研究。以羽色稳定遗传的莆田黑鸭和莆田白鸭为亲本进行正反杂交,F1代个体进行自群繁育获得F2代个体,观察2个世代的羽色情况。选取产蛋初期莆田黑鸭所产的白壳、青壳和黑壳蛋各30枚,测定蛋重、蛋壳强度、蛋白高度、哈氏单位、蛋黄颜色、蛋壳厚度、蛋黄重、蛋形指数和蛋黄比例,并进行分析。结果显示：F1代入孵种蛋634枚,出雏448只,公母比为208:240,羽色均为黑色;F1代群体自群繁育获得F2代种蛋,入孵344枚,出雏288只,公母比为119:169,羽色发生分离,黑羽:白羽为206:82;黑壳蛋的各项指标（蛋形指数除外）均显著或极显著低于白壳和青壳蛋,白壳和青壳蛋的大多数指标没有差异;在青壳蛋中,蛋重与蛋黄颜色呈显著相关。结果表明：莆田黑鸭黑-白羽性状的遗传符合单基因分离定律,白羽为隐性性状,控制该性状的基因位于常染色体上;莆田黑鸭白壳与青壳蛋的主要区别在于蛋壳颜色,黑壳蛋的蛋品质相对较差。 相似文献
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以父母代肉种鸡为材料，以血浆极低密度脂蛋白（very low density lipoprotein，VLDL）质量浓度为选择指标建立肉鸡高脂系和低脂系，个体测定一世代高、低脂系母鸡产蛋性能、种蛋受精率、孵化率、二世代6周龄体质量，观察血浆VLDL质量浓度选择效应。结果显示，一世代低脂系比高脂系早开产6．7d，低脂系40周龄和54周龄产蛋量显著高于高脂系零世代，一世代低脂系种蛋受精率、受精蛋孵化率、入孵蛋孵化率均优于高脂系；二世代高、低脂系6周龄体质量差异不显著。结果表明，对血浆VLDL质量浓度的低向选择使种鸡产蛋性能、种蛋受精率、孵化率产生了有益的间接反应，但对早期体质量没有影响。 相似文献
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京海黄鸡连续3个世代类胰岛素样生长因子-Ⅰ外显子3的多态性研究 总被引：1，自引：1，他引：0
以7、8、9世代京海黄鸡母鸡为试验材料,采用PCR-SSCP技术对IGF-Ⅰ基因外显子3多态位点进行研究,并计算基因型、基因频率、卡方值和部分遗传多态性指标。结果表明,A等位基因随着世代数的增加不断减少;3个世代之间基因型分布达到显著(P0.05)或极显著(P0.01)差异;遗传杂合度随世代数的增加而升高;该位点3个世代均为中度多态。初步推断选留的确对IGF-Ⅰ基因31位点造成了影响,该位点可应用于育种实践中。 相似文献
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根据缙云麻鸭的产业现状与发展需要,采用父系半同胞家系选育方法,辅以生化遗传标记育种技术,对缙云麻鸭进行了四个世代的提纯复壮,选育了缙云麻鸭Ⅰ系、Ⅱ系、青壳系三个纯系。经测定,各纯系母鸭平均见蛋日龄为82d,500日龄羽均产蛋量达到329.83枚、总蛋重21.65kg,蛋料比1∶2.86,分别比选育前提高10.38%、15.15%、13.64%,经统计分析差异显著(P>0.05);青壳系鸭青壳蛋比例核心群达95%以上,商品代达85%以上。 相似文献
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以7、8、9世代京海黄鸡母鸡为试验材料,采用PCR-SSCP技术对IGF-Ⅰ基因外显子3多态位点进行研究,并计算基因型、基因频率、卡方值和部分遗传多态性指标。结果表明,A等位基因随着世代数的增加不断减少;3个世代之间基因型分布达到显著(P＜0.05)或极显著(P＜0.01)差异;遗传杂合度随世代数的增加而升高;该位点3个世代均为中度多态。初步推断选留的确对IGF-Ⅰ基因31位点造成了影响,该位点可应用于育种实践中。 相似文献
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本文以庄河大骨鸡核心群78周龄的产蛋母鸡为试验材料,利用PCR-SSCP标记技术分析了ESR基因的遗传分布、群体杂合性等遗传信息,结果显示:ESR基因在庄河大骨鸡中存在三种基因型,即:CC型、CD型和DD型,三种基因型的频率分别为:0.245、0.335、0.42,C基因和D基因频率为0.4125和0.5875,多态信息含量为0.3245,属于中度多态;CC基因型鸡只的产蛋数、料蛋比显著高于其他两种基因型,差异显著(P<0.05);开产周龄、开产体重、产蛋高峰期和蛋重三种基因型间差异不显著(P>0.05)。ESR基因的CC型对产蛋性能有显著影响,但是否可作为研究该基因与庄河大骨鸡产蛋性能相关的重要遗传标记还需做进一步研究。 相似文献
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以京海黄鸡母鸡为材料,采用PCR-SSCP技术对IGFBP-3基因外显子1及内含子1部分序列多态位点进行研究,并计算基因型频率、基因频率、卡方值和部分遗传多态性指标。结果表明,在外显子1上没有检测到多态位点,在内含子1上检测到1个多态位点,该位点为中度多态,在160 bp处发生T到G的突变,导致BB、AB型的56日龄体重显著大于AA型(P＜0.05),AA型的11月产蛋数显著大于BB、AB型(P＜0.05)。由此初步推断,内含子1对产蛋及生长发育很可能有一定的促进作用,A为产蛋的优势基因,B为体重的优势基因。 相似文献
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试验旨在研究卵钙蛋白-32（ovocalyxin-32,OCX-32）、卵清蛋白（ovalbumin,OVA）基因多态性与蛋品质性状的关联性,寻找与蛋鸡蛋品质性状相关的分子遗传标记。采用PCR-SSCP技术对海兰褐蛋鸡父母代中OCX-32、OVA基因的多态位点进行检测,使用SPSS 22.0软件将不同基因型与海兰褐蛋鸡蛋品质性状进行关联分析,并进一步在子代中验证,寻找优势基因型。结果显示,OCX-32基因第6外显子中检测到AA、BB和CC 3种基因型,2个突变位点,分别位于7 018和7 116 bp;OVA基因第5外显子中检测到AA、BC、BB 3种基因型,2个突变位点位于4 296和4 323 bp。关联分析结果表明,海兰褐蛋鸡父母代OCX-32基因AA基因型的蛋黄重极显著高于BB和CC基因型（P < 0.01）;海兰褐蛋鸡父母代OVA基因AA基因型的哈氏单位及蛋白高度极显著高于BC基因型（P < 0.01）,显著高于BB基因型（P < 0.05）,AA基因型蛋白重显著高于BC基因型（P < 0.05）。在子代中验证进一步确定了OCX-32基因的AA基因型为调控蛋黄重的优势基因型,OVA基因的AA基因型为调控哈氏单位、蛋白高度和蛋白重的优势基因型。综上所述,OCX-32及OVA基因对蛋品质性状有一定影响,可作为蛋鸡的分子育种标记。 相似文献
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本文通过四个交配组合得到表型和基因型不同的九个组别,在相同遗传背景基础上比较了性染色体上慢羽(K)和快羽(K)基因,常染色体上显性白羽(I)和有色羽(i)基因对母鸡生产性能的影响。结果表明不同基因型对育成期死亡率无显著影响;含有k基因的母鸡组72周总蛋重比含有K基因的母鸡组较重;ii基因型的母鸡组比Ii基因型的母鸡组饲料报酬较好;各种不同基因型间蛋的品质均无显著差异。 相似文献
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Serological detection of experimental Salmonella enteritidis infections in laying hens 总被引：4，自引：0，他引：4
The antibody response of laying hens to experimental Salmonella enteritidis infection was evaluated in microagglutination, tube agglutination, and rapid whole-blood plate agglutination assays. Hens of three different ages were infected by either oral inoculation or horizontal contact transmission. Blood was collected at weekly intervals, and the presence of specific antibodies was assessed by reaction with antigens prepared from strains of S. enteritidis and S. pullorum. The sensitivity of detection of infected hens did not vary significantly between the assays, as all three tests effectively identified most exposed hens as seropositive. Within each test, however, variation was observed in the detection sensitivity when different antigens were used. The microagglutination titers of serum samples were determined by serial dilution. Antibody titers peaked at 1 to 2 weeks postinoculation and declined steadily, although most birds were still identified as seropositive at 10 weeks postinoculation. The mean microtest titers obtained with S. enteritidis antigens were higher than with an S. pullorum antigen, indicating greater test sensitivity. However, use of the S. pullorum antigen resulted in fewer false positives when sera from uninfected control hens were tested. The titers of contact-exposed hens peaked later and at lower values than did those of inoculated hens, but these two groups of hens had similar antibody titers after the third week postinoculation. 相似文献
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针对贵妃鸡在国内外珍禽市场上不可估量的发展前景,为了选育出贵妃鸡自别雌雄配套系,本研究根据伴性遗传基因的遗传原理和羽速基因的遗传特点,采用现代家禽育种方法对贵妃鸡第二世代表型慢羽公鸡进行了测交试验。采用人工授精,所产种蛋分别孵化。其中用13只表型为慢羽公鸡,与52只快羽母鸡组成第1类测交试验,结果每只公鸡的后代中都有快羽雏出现,且快慢羽比例几乎为1:1(217:232);由20只表型慢羽公鸡与80只慢羽母鸡组成的第2类测交试验,结果每只公鸡的后代中,也都有快羽雏出现,而且快慢羽比例几乎接近1:3(197:520)。可见,所用的33只公鸡经测交证明全为杂合体,同时表明两个不同质量性状测交结果完全符合孟德尔遗传定律。 相似文献
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本研究选取位于陕西省神木市境内的8个草地样地,采用“二值出现次数”野外调查法,得到样方中各植物种的出现次数数据,以此计算群落整体的物种多样性指数值,以及组成群落的各植物种不存在时的物种多样性指数值,利用这两个多样性指数值的差值,探明各植物种在群落整体物种多样性中的作用。研究结果如下：(1)8个草地样地中,对物种多样性作用最大的植物种并非该群落的第1优势种,而是优势地位处于第2～7位的植物种;(2)3个样地中第1位优势种占据了绝对优势,它们降低了群落整体的多样性;(3)物种在多样性中的作用大小整体上呈现单峰型变化趋势,即随着物种优势地位的降低,对数式增加达到最大值,然后指数或线性下降,最终趋近于0。综合显示,不同的草地群落中,在物种多样性中作用最大的不是第1优势种,占绝对优势地位的优势种降低了该群落的物种多样性。 相似文献
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Contamination of eggs by Salmonella Enteritidis has been a prominent cause of human illness for several decades and is the focus of a recently implemented national regulatory plan for egg-producing flocks in the United States. Salmonella Heidelberg has also been identified as an egg-transmitted pathogen. The deposition of Salmonella strains inside eggs is a consequence of reproductive tract colonization in infected laying hens, but prior research has not determined the relationship between the numbers of Salmonella that colonize reproductive organs and the associated frequency of egg contamination. In the present study, groups of laying hens in two trials were experimentally infected with large oral doses of strains of Salmonella Enteritidis (phage type 13a), Salmonella Heidelberg, or Salmonella Hadar. Reproductive tissues of selected hens were cultured to detect and enumerate Salmonella at 5 days postinoculation, and the interior contents of eggs laid between 6 and 25 days postinoculation were tested for contamination. Significantly more internally contaminated eggs were laid by hens infected with Salmonella Enteritidis (3.58%) than with strains of either Salmonella Heidelberg (0.47%) or Salmonella Hadar (0%). However, no significant differences were observed between Salmonella strains in either isolation frequency or the number of colony-forming units (CFU) isolated from ovaries or oviducts. Salmonella isolation frequencies ranged from 20.8% to 41.7% for ovaries and from 8.3% to 33.3% for oviducts. Mean Salmonella colonization levels ranged from 0.10 to 0.51 log CFU/g for ovaries and from 0.25 to 0.46 log CFU/g for oviducts. Although parallel rank-orders were observed for Salmonella enumeration (in both ovaries and oviducts) and egg contamination frequency, a statistically significant relationship could not be established between these two parameters of infection. 相似文献
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某种鸡场一群艾维茵父母代种鸡中出现“假性母鸡”,剖检发现输卵管畸形。这批种鸡在17日龄时发生过某传染病。进行发病情况调查、对病死雏鸡的剖检和开产期病死母鸡的剖检、病料鸡胚感染和传代试验及新城疫病毒干扰试验。结果,鸡胚感染中第3代出现侏儒胚,干扰组的新城疫血凝价均低于20,对照组新城疫血凝价高于40。综合分析,可以判定该雏鸡在3周龄发生的疾病是鸡传染性支气管炎,以及可以确定该鸡群中不少鸡只出现输卵管畸形是由鸡传染性支气管炎病毒早期感染而引起的。 相似文献
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本研究选择笼养和放养条件下49周龄的卢氏绿壳蛋鸡各20只（公母各半）,测定了其屠体性状。结果表明,饲养方式对卢氏绿壳蛋鸡的活重、屠宰率、半净膛率、全净膛率、胸肌率、腿肌率、腹脂率、翅重、心脏重、肝脏重、脾重、肠重、胃重和生殖器官重的影响均差异不显著（P>0.05）。饲养方式对公鸡的各项指标影响差异不显著（P>0.05）,而对母鸡的头重、颈重、脚重影响很大（P<0.01）;相同饲养条件下公鸡的全净膛率、腹脂率、头重、脚重、颈重、翅重、心脏重和肠重极显著高于母鸡（P<0.01）,对肝脏重、脾脏重和胃重的影响差异不显著（P>0.05）;笼养时公鸡的活重、腿肌率和生殖器官重显著高于母鸡（P<0.05）,而对半净膛率和胸肌率的影响不显著（P>0.05）;放养时母鸡的生殖器官重极显著的高于母鸡（P<0.01）;不同饲养条件下,公鸡头重、颈重、肠重、生殖器官重与屠宰率相关性不显著（P>0.05）;母鸡脚重、翅重、肠重、脾脏重与屠宰率的相关性显著（P<0.05）。 相似文献
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J. H. H. van Eck 《The Veterinary quarterly》2013,33(3):117-124
Summary Following EDS'76 virus (BC14 virus) infection of breeder chickens by the conjunctival route, vertical transmission occurred in the first week after infection. In the progeny which had been infected with EDS'76 virus by the vertical route, increasing haemagglutination inhibiting (HI) litres to BC14 virus and increasing numbers of birds with HI litres were observed from 3 weeks to 15 weeks of age. Sixty‐one per cent of the hens and 77 per cent of the cocks had 2log HI BC14 virus litres exceeding 4 at an age of 15 weeks. Some birds which had been serologically negative throughout the rearing period, seroconverted between 25 and 28 weeks of age. This phenomenon occurred in hens as well as in cocks. Simulation of stress twice during the laying period by injection of corticosteroid hormone did not increase the number of birds serologically positive to EDS'76 virus. EDS'76 was observed in the group of hens that was vertically infected, since egg production was significantly depressed between 28 and 34 weeks of age. Probably this was mainly the result of a production drop in the hens showing seroconversion at 27 or 28 weeks of age. In the group of fowl vertically infected with EDS'76 virus, serologically positive birds appeared to be protected for the greater part to BC14 virus challenge at 50 weeks of age, while negative birds seemed to be fully susceptible. Chicks hatched from eggs collected in the third and fourth week after infection of the dams had maternal antibodies. Fertility and hatchability of apparently normally shelled eggs seemed not to be affected after BC14 virus infection of the dams. Intensive contact with contaminated faeces is probably an indispensable condition for lateral transmission of the virus. 相似文献