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1.
为探讨在不同温度条件下粪便保存不同时间对球虫卵囊成熟力的影响，本实验将含有球虫卵囊的粪便在．20℃、4℃、20℃、28℃分别保存0h、24h、48h、72h，通过观察卵囊的孢子化率确定最佳保存条件。结果表明：相同保存温度条件下，保存0h、24h、48h、72h的E．tenella早熟耐药株卵囊的孢子化率依次降低。-20℃和28℃时孢子化率均未达到80％；在4℃时粪便保存24h的孢子化率达到80％以上，保存48h及以上时孢子化率极显著（P〈0．01）低于保存24h的孢子化率；在20℃时的孢子化率均达到80％以上。 相似文献
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为探讨温度对球虫消杀剂抑制鸡球虫卵囊孢子化的影响,试验以7%氨水作为对照组,设置1:50、1:100、1:150的球虫消杀剂溶液组,同时设置生理盐水对照组.各处理液分别在4℃和20℃下与柔嫩艾美耳球虫未孢子化卵囊在体外相互作用6、12和24h,然后用2.5%重铬酸钾溶液培养处理后的球虫卵囊,观察其孢子化率.结果表明:1:50、1:100、1:150球虫消杀剂在4℃分别处理6、12和24h的卵囊孢子化率均极显著(P<0.01)高于20℃下的对应处理组.球虫消杀剂在20℃下有更好的抑制球虫卵囊孢子化的作用. 相似文献
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为了筛选有效的球虫消毒剂,本研究将柔嫩艾美耳球虫卵囊分别与16种常用消毒剂和1种高效抗球虫药物溶液（250 mg/L妥曲珠利溶液）混合作用2 h然后在2.5%重铬酸钾溶液中孢子化培养,或混合作用4 h后接种14日龄雏鸡,根据卵囊孢子化率、孢子化抑制率、每克粪便卵囊数量（oocysts per gram of feces,OPG）、病变计分和血便情况评价消毒剂和抗球虫药物抑杀球虫卵囊效果。结果显示,8%氨水对未孢子化卵囊和孢子化卵囊均表现为100%的抑杀效果;250 mg/L妥曲珠利、3%甲醛、4%苯酚、0.5%过氧乙酸、5% NaOH+10% NaCl和5% NaOH对球虫卵囊活性具有一定的抑制作用,孢子化抑制率超过10%,但是对孢子化卵囊抑杀作用不明显;而剩余10种常用消毒剂对球虫卵囊没有明显的抑杀作用。氨水抑杀球虫卵囊条件优化的试验结果显示,1%~8%氨水与未孢子化卵囊作用1 h以上,均可100%抑杀球虫卵囊活性。粪便干扰试验结果显示,粪便不影响2%和4%氨水对球虫卵囊的抑杀效果。本研究结果说明常用消毒剂和抗球虫药物不能有效杀灭球虫卵囊的活性,而氨水是一种高效球虫消毒剂。本研究结果可为开发新型高效球虫消毒剂和球虫病控制提供参考。 相似文献
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为了解阳光照射对球虫卵囊孢子化率的影响,将未孢子化卵囊分别在阳光下照射2小时、4小时、6小时后,放在27～28℃恒温箱中培养,于第3天和第5天进行显微镜观察计数球虫卵囊孢子化率。试验结果表明,阳光照射对球虫卵囊的孢子化率有着明显抑制作用,随着光照时间的延长,球虫卵囊的孢子化率呈下降趋势。说明鸡球虫未孢子化卵囊对高温干燥的环境抵抗力差,阳光照射3～4小时,孢子化率明显下降12.67%￣26.00%。 相似文献
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球虫消杀剂（Oo-stat）的配方优化研究 总被引：1，自引：1，他引：0
为获得对鸡球虫卵囊有良好抑杀作用的球虫消杀剂最佳配方,将3种不同配方的球虫消杀剂配成1:20、1:30、1:40、1:50、1:60、1:80、1:100、1:150、1:200、1:300及1:400.分别对柔嫩艾美耳球虫未孢子化卵囊体外相互作用6h、12h和24h之后,培养观察其孢子化率.结果表明,配方一、配方二除1:300和1:400处理6h组及1:400处理12h组与对照组差异不显著外,其余各组均显著低于生理盐水对照组(P<0.05);1:20、1:30、1:40、1:50、1:60及1:80的球虫消杀剂溶液分别处理卵囊6h、12h和24h后孢子化率均低于5%;配方三1:20、1:30、1:40、1:50、1:60及1:80的球虫消杀剂溶液分别处理卵囊12h和24h后孢子化率均低于5%,但是当处理时间为6h时,其孢子化率较高.研究表明配方二具有优良的抑杀鸡球虫卵囊的作用. 相似文献
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《当代畜牧》2020,(4)
为了研究青蒿、秦皮这2种中草药不同质量浓度溶液对兔球虫卵囊孢子化的影响,笔者采用饱和食盐水漂浮法分离兔球虫卵囊,再将未孢子化的兔球虫卵囊分别置于不同质量浓度(0.25 g/m L、0.50 g/m L、1.00 g/m L)的青蒿及秦皮中药提取液中,28℃恒温连续培养5 d。每24 h在显微镜下观察兔球虫卵囊的孢子形成情况,计算兔球虫卵囊孢子化率。试验结果表明,2种药物对球虫卵囊孢子化均有抑制效果,但在相同时间、相同浓度时秦皮的抑制作用高于青蒿,且随着药物浓度的增加,对球虫卵囊的孢子化抑制效果也增强。5 d后抑制效果最好的是1.00 g/m L的秦皮,孢子化率为62%;抑制效果最差的是0.25 g/m L的青蒿,孢子化率为85%。 相似文献
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《中国畜牧兽医》2018,(12)
为了筛选有效的球虫消毒剂,本研究将柔嫩艾美耳球虫卵囊分别与16种常用消毒剂和1种高效抗球虫药物溶液(250mg/L妥曲珠利溶液)混合作用2h然后在2.5%重铬酸钾溶液中孢子化培养,或混合作用4h后接种14日龄雏鸡,根据卵囊孢子化率、孢子化抑制率、每克粪便卵囊数量(oocysts per gram of feces,OPG)、病变计分和血便情况评价消毒剂和抗球虫药物抑杀球虫卵囊效果。结果显示,8%氨水对未孢子化卵囊和孢子化卵囊均表现为100%的抑杀效果;250mg/L妥曲珠利、3%甲醛、4%苯酚、0.5%过氧乙酸、5%NaOH+10%NaCl和5%NaOH对球虫卵囊活性具有一定的抑制作用,孢子化抑制率超过10%,但是对孢子化卵囊抑杀作用不明显;而剩余10种常用消毒剂对球虫卵囊没有明显的抑杀作用。氨水抑杀球虫卵囊条件优化的试验结果显示,1%～8%氨水与未孢子化卵囊作用1h以上,均可100%抑杀球虫卵囊活性。粪便干扰试验结果显示,粪便不影响2%和4%氨水对球虫卵囊的抑杀效果。本研究结果说明常用消毒剂和抗球虫药物不能有效杀灭球虫卵囊的活性,而氨水是一种高效球虫消毒剂。本研究结果可为开发新型高效球虫消毒剂和球虫病控制提供参考。 相似文献
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毒害艾美耳球虫卵囊先孢子化后贮存和先贮存后孢子化对其致病力的影响 总被引：2，自引：0，他引：2
新鲜收集的毒害艾美耳(Eimeria necatrix)球虫卵囊，一部分未孢子化即贮存在4℃冰箱，另一部分在28℃恒温水浴根荡孢子化48小时后再贮存在4DC冰箱。2个月后将先贮存的未孢子化卵囊在上述同等条件下进行孢子化48小时，然后两部分卵囊作致病力比较试验。结果表明，先贮存后孢子化卵囊的孢子化率和致病力都明显下降，先孢子化再贮存的卵囊存放2个月后其致病力各项指标也略有下降。 相似文献
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Feces containing Isospora suis oocysts were collected from naturally- and experimentally-infected pigs from four different areas of the United States. The unsporulated oocysts were cleaned, concentrated, mixed with 2.5% aqueous potassium dichromate solution, poured into petri dishes to a depth of 5 mm, and incubated at 25 degrees C. The oocysts were examined with a microscope at 12 h intervals and the stages of sporulation present were counted. Although a few oocysts were completely sporulated after 12 h of incubation, in most fecal samples the majority of the oocysts were not completely sporulated until 24 or 36 h. In the present study, the sporulation time of I. suis oocysts was considered to be less than or equal to 48 h. There were no major differences in the sporulation times of I. suis oocysts from the different sources. 相似文献
12.
Isospora suis is a coccidian parasite infecting piglets soon after birth. While the gross epidemiology of I. suis is well known, little knowledge exists on the ecology of the oocysts. To study the development and survival of oocysts of I. suis under controlled laboratory conditions, known numbers of oocysts ( approximately 200 in each of 4 replicates) were exposed to all combinations of 4 relative humidities (53-100% RH) and 3 temperatures (20 degrees , 25 degrees , 30 degrees C). Determination of viability was based on morphological and fluorescent properties of the oocyst as well as on the permeability of the oocyst wall characterized by inclusion/exclusion of the fluorescent dye propidium iodide. The viability of the oocysts was studied over time by fluorescence and light microscopy until <5% of the oocysts were considered to be viable. The sporulation rate increased with temperature, however, the infective sporocyst stage was reached within 24h at all temperatures, while RH did not seem to affect sporulation. Results show a rapid reduction in viable oocysts exposed to high temperatures (25 degrees C and 30 degrees C) in combination with low relative humidities (53% RH and 62% RH), at which conditions oocysts died within 24h. Viability was higher when oocysts were exposed to higher relative humidities (75% RH and 100% RH) as well as a lower temperature (20 degrees C). However, even at 75% RH the oocysts died within 24-60 h at 30 degrees C to 20 degrees C, respectively, while the most favourable condition appeared to be 100% RH and 25 degrees C at which condition the percentage of viable oocysts decreased from 100% to 17% in 96 h. The results indicate that it may be possible to reduce the infection pressure of I. suis in modern sow herds by changing the environmental conditions and/or the management within the farrowing pens, and thereby increase animal welfare without relying on the use of routine medication. 相似文献
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采用不同方法处理沙生针茅(Stipa glareosa)种子,测定沙生针茅种子发芽率和种子出苗率,以探明影响沙生针茅种子萌发和播种出苗的制约因素。结果表明:60℃蒸馏水浸泡种子24 h,种子吸水率、发芽率、发芽势分别为26.3%,38.0%和32.0%;-20℃、20℃低温变温处理96 h,发芽率和发芽势分别为46%和48%;用80 mg/L GA_3水溶液浸泡种子24 h,发芽率和发芽势分别为54%和48%;沙埋深度会影响沙生针茅种子发芽和出苗,沙埋0.5 cm沙生针茅的种子发芽率和幼苗出土率最高;埋深超过2cm的深度,发芽率和出苗率降低;埋深6~8 cm,随着沙埋深度增加,出苗率显著减少;当埋深8 cm的深度,沙生针茅出苗率为0。 相似文献
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Post-weaning coccidiosis occurs in dry conditions in the dry tropics of north Queensland. Despite heavy faecal contamination, oocysts are difficult to detect in cattle yards. Experiments demonstrated the destruction of Eimeria bovis, E. ellipsoidalis and E. zuernii oocysts by natural factors in simulated yard conditions. Desiccation was rapid and temperatures as high as 48 degrees C developed within yard floor material although air temperatures did not exceed 27 degrees C. Oocyst numbers fell by 50% after 24 h, by 98% after 48 h, and were undetectable after 72 h. Oocysts were seen to collapse, and no development towards sporulation was noted. 相似文献
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Feed additive anticoccidials currently used in Japan were examined for possible effects on oocyst sporulation of Eimeria tenella. Monensin, salinomycin, lasalocid, amprolium plus ethpabate, amporolium plus ethopabate plus sulfaquinoxaline, clopidol, or nicarbazin were given to chickens continuously via the feed at the recommended use level or one-half of that level. Oocysts discharged in feces 7-8 days post inoculation (PI) were collected and aerated for sporulation. Low sporulation rate was noted, when clopidol at 62.5 mg kg-1 was given from 4 to 7 days PI. These oocysts were as infective as oocysts from controls, based on weight gain, feed efficiency, gross lesion score of cecae, and oocyst count 7 days PI. The results of the study indicated that the second schizogony and gametogony are vulnerable to clopidol, as evidenced by oocyst sporulation, but infectivity of these sporulated oocysts was not affected. 相似文献
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Toxoplasma gondii oocysts are excreted nonsporulated in the feces of the cats into the environment. These oocysts must undergo sporulation to become infectious. Little is known about the factors that influence sporulation of T. gondii oocysts. The present study examined the survival of nonsporulated oocysts under refrigerated conditions over 11-week observation period. Microscopic examination of oocysts indicated that no visible development occurred under refrigerator conditions. The nonsporulated oocysts retained their ability to sporulate when placed at room temperature. The numbers of visually viable appearing oocysts decreased over time. Some oocysts in all samples were infectious for mice despite being refrigerated for up to an 11 weeks before undergoing sporulation. Results indicate that nonsporulated oocysts can survive in the environment for at least 3 months and retain their ability to become infectious when placed under appropriate conditions. 相似文献
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Kimbita EN Samani PM Machange EN Silayo RS 《The Onderstepoort journal of veterinary research》2005,72(3):251-254
A wild strain of Eimeria tenella was isolated and utilized for immunization studies. Its optimal sporulation was attained at room temperature 24-25 degrees C after 24-48 h. Two groups of chicks were immunized by dosing a graded dose of five oocysts/chick/day for 6 days followed by 50 oocysts/chick/day for 7 days. A third group was not immunized and served as a negative control. Immunized chicks gained mass at the same rate as unimmunized ones, but when challenged with 200,000 oocysts/chick, mass gains declined in the unimmunized group. The growth rate of immunized chicks was not affected by challenge (P > 0.05). Upon challenge, unimmunized chicks produced significantly more oocysts than immunized chicks (P < 0.005). Immunized chicks withstood a challenged with 200,000 oocysts/chick without developing any clinical signs whereas the unimmunized chicks developed typical clinical signs of coccidiosis. Unimmunized chicks had significantly more severe lesions in the caecum than any other group (P > 0.005) and also produced significantly more oocysts than any other group (P > 0.005). 相似文献