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1.
近年来杨潜叶跳象对河西走廊地区胡杨(Populus eaphratica)林的危害日益加剧。在金塔县杨潜叶跳象的调查中发现,金塔县气温超过10℃时,杨潜叶跳象出蛰恢复活动,出蛰后立即上树为害胡杨,5月下旬开始化蛹,6月上旬为化蛹盛期。通过喷施5%高效氯氰菊酯乳油1 000倍液,2.5%溴氰菊酯乳油2 000倍液对杨潜叶跳象进行防治,结果表明,4月初在树下喷施1 000倍5%高效氯氰菊酯乳油的胡杨平均好叶率明显高于清水对照胡杨平均好叶率,林内及树下喷施1 000倍5%高效氯氰菊酯乳油,蛹的平均校正死亡率分别为99%、100%,成虫几乎无法完成羽化。  相似文献   

2.
在其它桑园管理措施一致的前提下,分别就桑小灰象虫不同危害程度与桑叶产量的关系进行了调查。结果是桑小灰象虫被害株(夏伐)不同危害程度虽然对春叶产量的影响不大,但对秋叶产量的影响很大,同时影响到次年的春叶产量。应认真做好该虫的预测预报工作,同时加大该虫的防治力度。  相似文献   

3.
2000年在广西北流潮塘、荔宝、花果山等果场进行了平腹小蜂防治荔枝蝽象试验,总面积约20hm2,8~10年生龙眼、荔枝树约4000株.结果为: 在放蜂区和对照区内,荔枝蝽象卵寄生天敌平腹小蜂、跳小蜂的总寄生率分别为94.3%和18. 9%,相比效果明显,同时,果园中若虫数量显著降低,控制在经济危害阈值之下.  相似文献   

4.
紫花苜蓿是一种优质的豆科牧草,种植多,面积大,因此较容易产生虫害。紫花苜蓿的虫害会严重影响紫花苜蓿的产量造成严重的经济损失。通过对紫花苜蓿生长过程中各个阶段的观察和研究,总结了几种紫花苜蓿生长过程中常见的病虫,并根据不同病虫研究了相应的防治方法。研究发现,主要的病虫有苜蓿叶象、蚜虫、芫菁、车轴草叶象甲、车轴草根瘤象共5种。  相似文献   

5.
采用喷雾法对8种药剂对苜蓿叶象及条纹根瘤象进行室内毒力测定,结果表明:2%噻虫啉微囊粉剂对苜蓿叶象四龄幼虫的活性较高,其 LC50为107.408 mg/L,4.5%高效氯氰菊酯微乳剂的活性最低,其 LC50为549.342 mg/L;8种杀虫剂对三龄幼虫的 LC50为140.176-453.784 mg/L。40%毒死蜱乳油对条纹根瘤象成虫活性较高,其 LC50为71.017 mg/L,其次为2%噻虫啉微囊粉剂,其 LC50为80.157mg/L。  相似文献   

6.
独玉贞 《北方蚕业》2000,21(2):24-25
桑象虫属鞘翅目,象虫科,船象属,以成虫在春季食害冬芽及萌发后的嫩芯.受害桑树发芽率降低,影响春叶产量.夏伐后可继续为害剪口以下的定芽和新梢.严重时可将整株桑树吃光,不能萌发,造成秋叶严重减产.为了摸清桑象虫在本地区的发生规律,找出最佳防治技术措施,作者于1998年至1999年进行了对桑象虫的防治试验,同时在较大桑园面积内进行示范,效果很好.现将试验结果综述如下:  相似文献   

7.
近几年,抗虫棉因其抗棉铃虫效果好,可以显著降低防治棉铃虫次数,大量节省人力、物力、财力而广为种植。但抗虫棉只对棉铃虫等鳞翅目害虫具有防治效果(甜菜夜蛾除外),因为防治棉铃虫用药次数的明显减少,对一些原先的次要害虫的兼治作用显著降低,发生加重,甚至有上升为主要害虫的趋势,而农民多对此认识不足,为棉花生产埋下隐患。抗虫棉田主要害虫为棉蚜、叶螨、棉盲蝽和棉尖象。  相似文献   

8.
桑椹菌核病的危害是制约果桑生产发展的重要因子。针对生产实践中存在因桑树花期识别困难而错过最佳防治时期,造成桑椹菌核病严重危害的情况,探究以易于观察的桑树开叶数辅助花期识别确定防治适期的可行性。连续3年对大10、红果2号、白玉王、嘉陵30号4个花叶同开果桑品种的开叶数与花期进行调查,结果显示花叶同开的果桑品种开叶数与花期高度吻合:84%以上植株的开叶数达4片叶时即为初花期;84%以上植株的开叶数达6片叶时为盛花期;81%以上植株的开叶数达8片叶时为谢花期。采用常规化学药剂进行桑椹菌核病的田间防治时,依据开叶数确定防治适期与通过花期判断确定防治适期的防治效果无显著性差异,且2组试验的校正防效均91%。初步认为,在生产实践中可以利用通过桑树的开叶数观察辅助花期观察确定桑椹菌核病的防治适期。  相似文献   

9.
摩特矮象草是美国选育成功的一种高产优质饲草,又称美国矮象草。1987年从美国引入我国广西。1996年我局引种试种,该草表现出高产优质、饲喂效果很好等特点,是近几年我县开展种草养畜、养鱼项目的重点推广饲草品种。1)生物学特性。摩特矮象草是禾本科狼草,属多年生草本植物,茎丛生,株直立圆形,茎粗1~2cm,高100~150cm;节短而多,一般有10~18节,多的可达20节以上,成熟时节间有黑粉;叶互生,叶鞘包茎,叶面有少量茸毛,叶肋白色,叶绿色,叶质厚,一般叶长50~90cm,叶宽2~4cm,有细密锯齿状叶缘。一蔸的叶片覆盖面积达1m2左右。在我县,有个别植株开…  相似文献   

10.
为了探讨木薯杆、木薯叶更有效的饲用途径,本试验用木薯杆、叶与巨菌草1∶1混合青贮,并加入益生菌、糖蜜等改善其适口性~([1]),饲喂泌乳奶水牛。结果:混合青贮搭配木薯杆叶的比例可能稍大,适口性较差,用量代替象草的10%和20%时,平均产奶量分别下降3.9%和10%(p0.05);对于乳品质的影响不大,代替象草10%组的各项乳指标有所上升(p0.05),代替象草20%组乳糖含量下降0.062个百分点(p0.05)。从本次试验结果看,木薯杆、叶可制作青贮饲喂奶水牛,但占比应小于50%。  相似文献   

11.
The muscular architecture of the bovine omasal laminae was examined. The omasal laminae had three thin smooth muscle layers which consisted of an intermediate layer and two lateral layers. The muscle bundles of the intermediate layers ran radially in the laminae and those of the two lateral layers ran parallel to the free border of the laminae. At the free border, three types of the muscular architecture were observed. In a histological study, the muscle bundles of the intermediate layer penetrated into the connective tissue around the smooth muscle fasciculi of the inner layer of the tunica muscularis of the omasal wall and attached to the bundles of both the inner layer and of the outer layer of the tunica muscularis. These results indicate that a re-evaluation of the muscular architecture in the omasal laminae is required to facilitate better understanding of the omasal morphology and physiology.  相似文献   

12.
Norwegian sheep were investigated for globidial schizont infection in the abomasum. The frequency of infection was found to be 78.2 %. Light microscope studies of the various mature schizonts revealed the existence of four morphologically different merozoites, small A, small B, intermediate and long forms. Each globidial schizont was found to contain only one form of these merozoites. However, these four schizont types occurred in the same abomasum.The intermediate form of globidial schizont merozoites was investigated by the aid of an electron microscope, with the aim of comparing its internal morphology with that previously published for Eimeria species. A striking resemblance was observed between the fine structures of the intermediate merozoite and that of Eimeria species, particularly the first generation merozoites described in giant schizonts of Eimeria bovis.The present status of globidial schizonts infecting the abomasum of sheep was discussed. It was concluded that these four forms of merozoites could represent different generations of one Eimeria species or different E. species producing giant schizonts in the abomasum.Due to the practical difficulties in studying the life histories of the different Eimeria species infecting sheep, it was proposed that the in vitro propagation of the individual species in cultured cells may shed some light on the corresponding asexual, as well as the sexual, stages. This would offer a new approach to the study of the ultra-structure of the developing parasite.  相似文献   

13.
Age-dependent variations in the immunolocalization of fibronectin (FN) in the thymus were investigated in 1-, 6-, 12- and 20-month-old male and female Swiss albino rats (Rattus rattus) at the light-microscopic level and the changes with ageing in the histological structure of the thymus were also studied. There were no significant differences in the age-dependent variations in the immunolocalization of fibronectin or in the histological structure of the thymus between male and female rats of the same age but there were increases with ageing in the fibronectin content of the thymic capsule, the connective tissue between the lobules, around blood vessels, and in the medulla and cortex of thymus. The connective-tissue content between lobules, fat cells, Hassall's corpuscles, the thickness of capsule and the ratio of the medulla to the cortex of the lobules showed age-dependent increases in the thymus of rats of both sexes. Decreases in the organ weight/body weight ratio were also observed with ageing.  相似文献   

14.
乳腺炎是影响奶牛生产性能及健康最常见、最严重的疾病之一,可以导致奶牛淘汰、养殖场(户)经济损失。该病常用抗生素治疗,但易产生耐药性,畜产品存在抗生素残留,不利于奶牛养殖业绿色健康发展。益生菌具有增强奶牛免疫力、降低发病率和改善生产性能的优势,可替代抗生素,有良好的应用价值。本文对奶牛乳腺炎危害、益生菌有益作用和替代抗生素治疗的潜质进行综述,推动奶牛养殖业绿色、健康发展。  相似文献   

15.
【目的】 研究超排处理对家兔生殖器官组织形态和激素水平的影响。【方法】 将12只家兔分为试验组和对照组,每组各6只,在试验组家兔大腿内侧肌内注射70 IU孕马血清促性腺激素(pregnant mare serum gonadotropin,PMSG),72 h后同位置注射100 IU人绒毛促性腺激素(human chorionic gonadotropin,hCG),对照组均同时注射等体积生理盐水。试验组与对照组均采取与公兔合笼刺激诱导排卵,合笼24 h处死家兔并采集卵巢、输卵管、子宫,测量卵巢长度、宽度、厚度,子宫长度、宽度、周长、子宫壁厚度和输卵管长度、漏斗部宽度、峡部宽度、壶腹部宽度,并将卵巢制作成组织切片,通过HE染色研究卵巢卵泡变化;分别在注射PMSG前、注射hCG前及处死前采集对照组和试验组家兔耳缘静脉血,用ELISA法检测血清中抑制素(inhibin,INH)、促卵泡素(follicle-stimulating hormone,FSH)、促黄体素(luteinizing hormone,LH)、雌二醇(estradiol,E2)和孕酮(progesterone,P4)的含量。【结果】 与对照组相比,试验组卵巢组织重量、长度、宽度、厚度、充血卵泡数、排卵点数和闭锁卵泡数均极显著增加(P<0.01),卵巢内次级卵泡的直径显著变小(P<0.05);输卵管长度、壶腹部宽度和子宫宽度均显著增加(P<0.05),输卵管漏斗部宽度和子宫长度均极显著增加(P<0.01)。在3个不同采血时间,对照组家兔血清中INH水平呈递增趋势,在注射hCG前和处死前试验组INH含量均显著低于对照组(P<0.05);注射hCG前,试验组血清中FSH含量显著高于对照组(P<0.05),而在处死前试验组血清中FSH含量显著低于对照组(P<0.05);注射hCG前和处死前试验组血清中LH含量均显著高于对照组(P<0.05);试验组与对照组家兔血清中P4和E2含量在各时间点差异均不显著(P>0.05)。【结论】 70 IU PMSG+100 IU hCG组合的超排处理使家兔的卵巢体积增大、表面排卵点数增多,并协同内源激素作用于卵巢,获得较好的超排效果。  相似文献   

16.
With the wide application of the artificial insemination (AI) in animal husbandry,the utilization rate of excellent sire got greatly improved.The key point of AI is predicting the time of ovulation and insemination accurately.It is also the point which the animal husbandry technologists highly concerned to improve the application effect of AI.Estrus and ovulation are regulated minutely by reproductive hormones in vivo in farm animals.Timed artificial insemination (TAI) is based on the synchronization of estrus and ovulation,both of which are triggered by reproductive hormones.So the optimal time for AI could be determined from the reproductive hormone treatment.The purpose of TAI is to improve the reproduction performance of farm animals,reduce the workload of identification of estrus,and promote batch management.This review mainly summerized the principles of TAI and its applications status,and the prospects was also discussed.It would provide a reference for the research and application of new reproductive technology in farm animals.  相似文献   

17.
随着人工授精技术在畜牧业中的广泛应用,优秀种公畜的利用率得到了极大提高。而人工授精成功的关键是输精的准确性和及时性,因此如何准确预测排卵时间及输精时间是提高人工授精效果的重要途径,也是当前畜牧工作者高度关注的问题。家畜的发情排卵受到体内生殖激素的精密调控,定时输精技术就是在利用生殖激素进行同期发情、同期排卵的基础上,通过调控母畜的发情和排卵来确定人工输精的最佳时间,以期达到提高家畜繁殖性能、减少发情鉴定工作量和促进养殖场批次化管理的目的。作者综述了家畜定时输精的原理及当前的应用现状,同时对其发展前景进行了展望,以期为畜牧业繁殖新技术的研究和应用提供参考依据。  相似文献   

18.
The objective of this study was to examine whether susceptible calves grazing together with second-year resistant heifers are less exposed to trichostrongylid infection than are calves grazing on their own. Two groups of animals representing each age category were turned out onto pasture on 24 May 1997 and grazed at comparable stocking rates. The grazing of calves and heifers together was compared to groups of each age category grazing separately. The results indicated that herbage larval counts were significantly reduced in the second part of the grazing season on the plot grazed by the mixed group compared to the plot grazed by the first-season calves only. The mixed grazing strategy protected the young calves and no clinical signs were observed in this group, while most of the calves that grazed alone exhibited clinical signs. The availability of herbage was reduced towards the end of the season, with subsequent competition for the grass forcing all the animals to graze the tufts around the faecal pats, where the quality of the grass is poor and the numbers of infective larvae are high. The effect of this was visible in the form of increased parasite burdens in the calves that were grazed together with the heifers, confirmed by increased blood serum pepsinogen concentrations and reduced daily weight gains in the second part of the grazing season. The lower numbers of infective larvae on the pasture were probably achieved through the heifers ingesting many of the larvae but subsequently depositing relatively few eggs, since they had acquired some degree of resistance against trichostrongylid infections during their first grazing season. Thus they did not suffer any parasitological ill-effects during mixed grazing with first-season calves.  相似文献   

19.
豪猪雌性生殖器官的解剖研究   总被引:4,自引:4,他引:0  
为了解雌性豪猪的生殖生理,为其发情鉴定、催情技术、人工授精、胚胎移植、体外受精等人工繁殖技术方面的研究提供基础依据,对成年雌性豪猪的生殖器官进行了系统解剖研究。结果表明,雌性豪猪的性腺没有明显的季节性变化,但是在发情周期的不同时期卵巢有不同的变化,当母豪猪发情后,卵巢表面有成熟的卵泡,使整个卵巢体积增大,发情期过后,则卵巢相对缩小。其它生殖器官也都具有各自的解剖特征。  相似文献   

20.
近年来我国奶牛养殖业迅速发展,犊牛作为发展养牛业的主要基础,也越来越受到人们的关注。提升犊牛成活率、规范初乳饲喂规程、降低犊牛应激反应,提升环境舒适度,是改善犊牛福利的主要措施。提升犊牛饲养管理福利,对奶牛终身产奶量的提升有积极的促进作用。本文从提高犊牛接产成活率,增强机体免疫机能,减缓机体应激,提高犊牛舒适度等方面综合分析了提高犊牛福利、促进奶牛健康养殖的关键点,旨在提升牛只健康养殖水平,为促进我国奶业蓬勃发展提供技术支持。  相似文献   

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