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蚕种质量优劣是项综合性的系统工程,其中杂交率是衡量杂交种质量优劣的重要指标.如何提高一代杂交种的杂交率,是蚕种场工作的重点之一,也是必须解决的问题.近年来,蚕种生产单位以扩展原蚕区繁育蚕种来提高经济效益和解决劳动力的矛盾,给杂交率的提高带来了一定的难度.我场从过去的专业场逐步转向原蚕区饲育就地收茧制种、原蚕区饲育收茧回场部制种和场部自育自制三种生产形式.尽管生产形式多,工作复杂,几年来杂交率不但没有下降,还有所提高.90年省蚕种质量抽样调查平均为99.76%,91年下乡农户跟踪调查为99.84%,92年省蚕种质量抽样调查平均为99.90%,下乡农户跟 相似文献
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进入90年代,蚕桑生产的迅猛发展,蚕种生产亦大幅递增.盐城市蚕种生产由1988年的40万张上升到1995年的120多万张.面对巨大的生产压力,低水平扩张生产规模的农村原蚕区应运而生.据1995年统计,盐城市原蚕区制种量占全市生产总量的75%,随之而来的是蚕种质量下降.1996年全省蚕种生产进入调整阶段,以追求数量型转向为以"防微"为中心抓质量求生存阶段.盐城市的蚕种生产自1998年全部转入场内生产,实行春秋并重的蚕种生产布局.针对春季秋季蚕种生产上微粒子病发生的不同传染规律,有的放矢,实施不同的"防微"技术路线,执行全年不同时期的"防微"技术重点,有效地控制了蚕种生产微粒子病的蔓延,无毒批蚕种明显得到提高. 相似文献
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<正>目前蚕种生产和用种矛盾日益突出,主要表现在两个方面:一是蚕种安全冷藏浸酸日期,与农村用种日期,时间非常接近,中秋用种浸酸速度跟不上;二是农村中秋蚕种质量事故时有发生,孵化率不稳定.针对这些特点,我们进行了积极大胆的探索,深化改革,加强管理,加快技术改造,把好蚕种入库、冷藏、浸酸、配发关,在提高日浸酸量和质量上下功夫,经过3年的摸索,日浸酸量提高到4万多张,基本满足了中秋用种的需要,质量也明显的提高,1994年农村中秋蚕种孵化率在97%以上,其余的孵化率都在95%以上.我们的做法主要有以下几个方面: 相似文献
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我市秋期蚕种生产任务繁重,年生产任务均在15-20万张之间,占全年生产任务的40%—50%。但处在天气变化大,桑园害虫多,繁殖快,治虫难度大以及饲养环境恶劣,病菌病毒肆虐且情况复杂的季节,要实现蚕种秋繁优质稳产,必须做到精心管理,决不能掉以轻心。历年来总站和公司要求各场树立起品牌意识,认真抓好秋期蚕种生产的各项管理工作和技术措施,保证了蚕种秋繁的优质稳产,提高了信誉度,保证了产品较高的市场占有率。2000年我市秋期生产蚕种165801张,占全年蚕种生产的39.34%,其中无毒蚕种150005张,占90.47%。2001年秋期生产蚕种267962张,占全年蚕种生… 相似文献
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介绍了安徽省金寨县蚕种总场的蚕种生产现状与提高蚕种质量的经验。金寨县蚕种总场创新机制,建立蚕种质量保证组织机制,把行业法规落实到蚕种质量监管细微深处,制定蚕种生产监管措施;通过建立丰产优质种茧育桑园、落实以防微为中心的质量管理措施,落实以提高良卵率、孵化率、杂交率为原则的质量监管措施,严格按照各项技术要求,把住各个生产环节,确保蚕种内在品质的提高;在母蛾检验的基础上,连续10年增加成品卵"国检",从1997—2009年金寨县蚕种总场,平均每年的蚕种合格率均在98%以上。 相似文献
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<正>《畜牧法》和农业部《蚕种管理办法》的颁布,标志着蚕种行业已步入依法管理的新阶段。为创建规范、和谐的蚕种生产与经营氛围,促进蚕种业的良性发展,江苏省加大宣传、贯彻《畜牧法》和《蚕种管理办法》的力度,严格实行蚕种生产、经营的许可制度,维护了蚕种市场秩序,促进了蚕种生产与质量水平的提高。2006年全省共生产一代种319万张,比合同计划增产6．4%,各级原种繁育计划均超额完成；2006年全省优良蚕种统一供种率达95%以上；经省法定蚕种质量检验机构对全年生产的1 369批319万张一代种进行母蛾检疫,合格率达99．68%；经对今年出库的本省生产的蚕种进行成品卵检疫,合格率100%； 相似文献
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20世纪80年代以来,我省一代杂交蚕种微粒子病发生经历了三个阶段(见图表1).第一阶段是1980～1995年,我省家蚕微粒子病处于低发期.从蚕种生产历史上看,这15年是我省蚕种生产发展最为迅速,蚕种生产量最大时期,尤其在九十年代初期全国家蚕微粒子病大暴发,"微防"形势不断恶化情况下,我省的微粒子病发生始终处于有效控制状态,最高年份毛种淘汰率仅为1.66%,"无毒率"高,蚕种质量稳居全国前茅.第二阶段1996～1999年,是我省家蚕微粒子病暴发期.年毛种淘汰率都在10%以上,1998年甚至高达15.48%,检验无毒蚕种比例急剧下降,全省没有一个"无毒"场,微粒子病在我省的流行呈"遍地开花"之势.第三个阶段为1999年以后,我省家蚕微粒子暴发的态势得到了基本控制,防治工作取得了阶段性成效.2000年我省蚕种生产淘汰率从1996～1999年平均12.17%下降到3.25%;2001年全省"无毒"比例已达71.04%,比1996-1999年的平均水平上升了15个百分点,重点产区"无毒"蚕种比例已达80%以上.这阶段我省形成了"三控一严"(即控制胚种传染、控制桑园虫害、控制环境污染和严格管理)家蚕微粒子病综合防治技术体系,全省建立了严格的预知检查体系,桑叶叶面消毒技术得到了大面积的推广应用. 相似文献
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德清县自1983年实行联产承包责任制, 桑地分户经营后,极大地调动了农民的生产 积极性,蚕桑生产得到了迅速发展,到1992 年全县饲育蚕种30.6万盒,蚕茧产量达到 11053t,比承包前的1982年蚕种增加69.3%, 蚕茧增加97.2%,创造了历史最高水平.但 1993年开始,蚕桑生产连年下降,到1999年 全县蚕种饲养量只有21.1万盒,总产蚕茧只 有7393t,比1992年蚕种下降了31.0%,蚕茧 下降33.1%.究其原因是多方面的,其中第 一轮桑园承包造成了地小块分散、管理不便、 工本浪费、效益低下,其他矛盾突出. 相似文献
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《广西蚕业》1977,(4)
在英明领袖华主席党中央抓纲治国的伟大战略决策和党的“十一大”路线指引下,我场胜利完成了今年的蚕种生产任务.蚕种质量也有很大提高.多化原种生产十八批,饲养量八百七十克,全年平均死笼率1.1%与七六年的1%不相上下,茧层量平均达0.17克比七六年平均0.155克提高9.6%,茧层率平均达15.4%比七六年平均14.7%提高0.7%.多化普通种生产八批,批批及格制种,平均死笼率2.1%避免了往年后期大批死蛹现象.更可喜的是秋蚕种生产,苏12原种的死笼率只有1.3%,茧层量达0.33克,打破了我场历年来最高纪录,茧层率达21.1%比七六年20.2%也有所提高.东34原种死笼茧率0.5%比七六年2.3%有很大提高,211原种死笼茧率1.2%比七六年2.2%也有提高,201原种茧层量达0.18克比七六年0.165克提高9%.7532,932原种也取得好成绩,没有死笼茧、原来计划制200张原种,结果制出481张,超2.4倍完成任务.普通种苏12东 相似文献
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目的：了解固原地区市售新鲜蔬菜寄生虫卵污染情况。方法：随机抽样分布于固原地区（黑城、彭阳、海原、红河、李寨）5个村镇菜市场的蔬菜,每个菜市场采购10种蔬菜（以凉拌蔬菜为主）各500 g,每种10份,共计500份,随意分发到当地农家,农家主妇第1次洗涤,笔者第2次洗涤,收集洗菜水各500 mL,分别标记。取沉淀物,用饱和盐水浮聚法制片,显微镜下观察,不论虫种检出一个虫卵或幼虫判为阳性,数据经统计学分析。结果：检查10种蔬菜,发现10种有蛔虫卵,9种有蛲虫卵,6种有钩虫卵,4种有绦虫卵,2种有鞭虫卵。500份标本中,2次洗涤后都检出了寄生虫卵（P〈0.05）,第1次洗涤检出率为23.82%,甘蓝最高,为32.86%,辣椒最低,为14.29%;第2次洗涤检出率为10.04%。还是甘蓝最高,为15.71%,西红柿最低,为5.71%。菜洗的次数越多,虫卵的种类越少,数量也越少。结论：固原市市售蔬菜寄生虫卵总体检出率较高,居民生吃蔬菜有感染寄生虫的机会,应注意提高防病意识。 相似文献
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High hydrostatic pressure processing (HPP) is an effective non-thermal treatment used to inactivate pathogens from a variety of food and food products. It has been extensively examined using prokaryotic organisms and protozoan's but has had limited study on metazoans. Treatment using HPP has been shown to be effective in inactivating nematode larvae in food and preventing embryonation of Ascaris suum eggs. We conducted experiments using eggs of the canine whipworm Trichuris vulpis collected from naturally infected dogs and A. suum eggs from naturally infected pigs. We observed a delay in development of eggs of T. vulpis in a preliminary experiment and conducted 2 experiments to test the hypothesis that appropriate HPP levels can induce a delay in embryonation of nematode eggs. In experiment 1, nonembryonated T. vulpis eggs in tap water were packaged in sealable bags and exposed to 138-600 megapascals (MPa; 1 MPa=10 atm=147 psi) for 60s in a commercial HPP unit. In a second experiment, nonembryonated eggs of A. suum were exposed to 138-600 MPa and treated for 60s in the same commercial HPP unit. Embyronation of T. vulpis eggs was delayed by 4 and 5 days for eggs treated with 207 and 241 MPa but eventually eggs developed and the numbers of embryonated eggs was similar to controls on day 55. Embryonation of T. vulpis eggs treated with 345 or 350 MPa was delayed by 9 days and never reached more than 5% of eggs embryonated. On day 55 post treatment, 95% of control nontreated T. vulpis eggs were embryonated, 100-65% of eggs treated with 138-276 MPa were embryonated, a maximum of 5% of eggs treated with 345-350 MPa were embryonated, and 0% of eggs treated with ≥ 400 MPa were embryonated. T. vulpis eggs treated with ≥ 400 MPa did not undergo cell division. Embryrnation of A. suum eggs was delayed by 4, 10, and 16 days for eggs treated with 207, 241, and 250MPa, respectively, compared to nontreated control eggs. A. suum eggs treated with 207 MPa eventually embryonated to similar % embryonation values as controls and 138 MPa treated eggs but eggs treated with 241 or 250 MPa were always <5% embryonated. A. suum eggs treated with ≥ 300 MPa did not undergo cell division. On the final day of examination at day 56 after treatment, the % of embryonated eggs was 92% nontreated controls, 94% treated with 138 MPa, 84% treated with 207 MPa, 2% treated with 241 or 250 MPa, and 0% treated with 276, 200, 345, 400, or 414 MPa, respectively. 相似文献
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Brand Z Cloete SW Brown CR Malecki IA 《Journal of the South African Veterinary Association》2007,78(4):195-200
The ostrich industry experiences a high rate of embryonic mortalities during artificial incubation of eggs. Embryonic deaths were studied from data recorded on 37,740 fertile eggs incubated artificially during the 1998-2005 breeding seasons. Roughly 10,000 eggs that sustained embryonic mortalities were classified according to the stage and nature of death, i.e. before 21 days of incubation, after 21 days of incubation, deaths after pipping and rotten eggs. Although infection may have played a role in approximately 1300 rotten eggs, no detailed knowledge of the pathogens involved was available. The remainder of deaths could not be related to pathogens and the deaths were thus generally referred to as non-infectious. The overall level of embryonic mortality in all the eggs studied was 28.5 %. Overall embryonic mortality was affected by incubator, with higher levels (57.0 %) found in eggs incubated in an African Incubator and also in eggs that were transferred between incubators during incubation (38.1%). Overall embryonic mortality also increased in eggs produced by older females. Eggs produced in the autumn had the highest level of embryonic mortality at 53.6 %, whereas eggs produced in the winter had a marginally higher level of embryonic mortalities of 29.2 % compared with eggs produced during summer (27.4 %). Eggs produced by South African (SA) Black males crossed to Zimbabwean Blue females had high levels of embryonic losses of 45.7 %. The embryonic mortality of eggs produced by SA Blacks or Zimbabwean Blue breeding birds subjected to pure breeding was similar at approximately 33-34 %, but embryonic mortality was improved in eggs produced by Zimbabwean Blue males crossed to SA Black females (27 %). Embryonic mortality was increased in eggs that were set directly (32.0 %) or subjected to longer than 6 days of storage (43.5 %). Embryonic mortality was affected by year. The results that were obtained will assist in determining non-infectious factors that have a negative effect on hatching success. Steps can thus be taken to eliminate such factors that may compromise hatching success. 相似文献
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A method similar to that used by Board and Board (1967) was used to determine the numbers of eggs penetrated by bacteria on 3 poultry farms in south-east Queensland. Significant differences in the percentages of penetrated eggs between the eggs of layer birds (9.7%) and the eggs of meat birds (16.1%) and between nest eggs (10.5%) and floor eggs (15.3%) were detected. The distribution of the numbers of penetration points was similar for nest and floor eggs for both types of bird and was independent of shell surface area or thickness. 相似文献
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选择320日龄海兰褐蛋鸡234只,共分A(对照组)、B、C3个处理组,采用生物保健型蛋白饲料(SBD)代替蛋鸡日粮中的部分豆饼,通过56d的饲喂试验。结果表明:用3%生物保健型蛋白饲料代替日粮中3%的豆饼时,平均蛋重、产蛋率、破软蛋率、采食量都与对照组无显著差异(P>0.05);用5%生物保健型蛋白饲料取代饲粮中5%的豆饼时,平均蛋重、破软蛋率、与对照组无显著差异(P>0.05),但产蛋率、采食量与对照组相比均有下降(P>0.01),在蛋的品质方面未产生不良影响,只是C组的蛋黄颜色比A、B组偏黄,铜(Cu)的含量偏高。由此可见采用生物保健型蛋白饲料代替蛋鸡日粮中3%的豆饼,效果最佳。 相似文献
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Nagy A Ziadinov I Schweiger A Schnyder M Deplazes P 《Berliner und Münchener tier?rztliche Wochenschrift》2011,124(11-12):503-511
Infections of dogs with Toxocara canis and Echinococcus multilocularis pose an infection-risk particularly for contact persons. We examined specimens of hair coat and faeces of 124 farm dogs, 118 household dogs, 49 kennel dogs, 15 puppies from two litters, and 46 red foxes. Microscopically identified eggs of Toxocara or taeniids were further investigated by species-specific PCRs. In farm dogs, eggs of E. multilocularis or T. canis were identified in each 2.4% of faecal samples, eggs of T. cati (gastrointestinal passage) in 7.3%, respectively. Household dogs excreted eggs of T. canis (0.8%) and of T. cati (2.5%). In kennel dogs, eggs of T. canis (4.1%), but not of T. cati were detectable. Coat samples contaminated with eggs of Toxocara spp. were found from farm dogs (5.6%), household dogs (1.7%) and kennel dogs (2.0%). Taeniid eggs were isolated from the coat samples from only two farm dogs (1.6%); a molecular species determination was not achieved. In six intrauterinely infected puppies, Toxocara-eggs were found in 17/38 samples taken within six weeks. No intact Toxocara eggs could be isolated from the coat of nine puppies from a second litter 13 days after deworming. Of the 46 red foxes investigated (dissection and faecal samples) 13 (28.3%) were infected with E. multilocularis and 20 (43.5%) with Toxocara. Eggs of taeniids and Toxocara were found in 13% (in three cases confirmed as E. multilocularis) and 21.7%, respectively, of the coat samples. None of the retrieved Toxocara eggs in the coat samples were embryonated. Thus, an infection of humans through the transmission of E. multilocularis eggs after direct contact with dogs or foxes is conceivable, whereas a corresponding infection risk by Toxocara eggs must be critically challenged. 相似文献
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破损种蛋一般认为不能用于孵化,而被废弃。笔者对三种较为简单易行的修补破损种蛋的方法进行了试验,证明了破损种蛋通过修补可与正常种蛋一样用于常规孵化。将破损种蛋按不同破损程度和形状、不同修补时间、不同修补材料、破损蛋与完好蛋、破损蛋修补与不修补分成五组进行对比试验,每组重复三次。经修补的破损种蛋,孵化率为80.15%,与正常种蛋孵化率(87.14%)差异不显著(P>0.05)。修补的破损种蛋孵化率显著高于未修补的破损种蛋孵化率,分别为81.24%和33.91%。用胶水、浆糊、透明胶带修补的破损种蛋孵化率分别为81.01%、80.16%、68.98%。将破损种蛋分成第二天修补、第四天修补、第六天修补三类,同时入孵,结果为第二天、第四天、第六天修补的孵化率分别为81.06%、76.28%、62.54%。由此可见,破损种蛋在内壳膜没有破裂的情况下,完全可以用来孵化。 相似文献
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Effect of egg storage upon the survival of Campylobacter jejuni in laboratory-infected fertile poultry eggs 总被引：1，自引：0，他引：1
Fertile eggs were infected by Campylobacter jejuni in the laboratory by a temperature differential method of inoculation, which resulted in up to 10% of the hatched birds carrying C. jejuni in the intestine. When infected eggs were stored for 5 1/2 days before incubation, the infection rate of the eggs had decreased to 20% or less when set, and no infected chicks were hatched. Inoculation of eggs after 8 days in storage also failed to yield infected chicks. In all cases, the hatch ratio was no different from that of uninfected control eggs. 相似文献
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In this study, we investigated the morphological identification of Toxocara canis and T. cati eggs on the basis of light and scanning electron microscopic (SEM) observations. T. canis and T. cati eggs used in this study were recovered from the uteri of respective gravid female worms. Measurement of egg size was not helpful in the differentiation of these species, because approximately 90% of eggs measured were of similar size. Using SEM, we were able to differentiate T. canis eggs from T. cati eggs based on their respective characteristic surface structures. Both species have subspherical eggs with markedly pitted surfaces like those of a golf ball, but the surface pitting in T. canis is more coarse than that in T. cati. In this study, however, these differences were not absolute, as 16% of T. canis and 29% of T. cati eggs showed surface pitting that was uncharacteristic of their species. Of the 16% of T. canis eggs that could not be differentiated by surface structure, 3% had pitting resembling T. cati, and the remaining 13% showed intermediate type surface pitting. Similarly, 5% of T. cati eggs resembled T. canis, and 25% of these were of intermediate type. Light microscopic observation yielded results similar to those of SEM, indicating that light microscopy is also a useful tool for the identification of Toxocara eggs. 相似文献
20.
为探讨夏季常温保存和低温冷藏两种储藏方式对鸡蛋品质的影响,选择540个鸡蛋随机分为9组,1组当天测定蛋品质,3组置于28.31 ℃、湿度为68.13%的室温下保存,5组置于4~8 ℃的冷藏室保存,分别于第7、14、21、42和56 d测定蛋品质。结果表明,常温储藏的鸡蛋随着存放时间延长,鸡蛋品质不断下降,储藏21 d后,蛋重降低5.30%（P<0.05）,蛋壳厚度变薄（P<0.05）;哈氏单位随着储藏时间的延长迅速下降,第0 d比第21 d的哈氏单位值高59.18%（P<0.05）;蛋黄比率随储藏时间的延长有不断变大的趋势,第0 d的蛋黄比率比第21 d低15.58%（P<0.05）。低温冷藏的鸡蛋储藏到21 d时,仅哈氏单位比第0 d低6.78%（P<0.05）;冷藏到56 d时,蛋重和哈氏单位比第0 d分别降低5.63%和15.07%（P<0.05）,蛋黄比率提高了5.21%（P<0.05）。试验表明,鸡蛋在室温下的新鲜度适宜保存期不应超过21 d;低温冷藏时可以保存到56 d。 相似文献