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柑橘木虱是柑橘新梢期的重要害虫,也是传播柑橘黄龙病的主要自然虫媒,其种群数量越大,越有利于黄龙病的扩散,因此是一种重要的柑橘经济害虫。本研究采用五点调查法,监测了2018年4月至12月桂北地区失管果园柑橘木虱种群发生动态,并利用实时荧光定量PCR方法明确了感病果园柑橘木虱含黄龙病菌量的动态规律。结果表明,2018年桂北地区失管果园柑橘木虱种群发生动态具有3个高峰期,分别出现在6月、9月和11月。柑橘木虱携带黄龙病菌量在4 ~ 7月处于较低水平,随后逐步上升并于10月达最高值,其动态变化为单峰型。此外,柑橘木虱年均含菌量可能与性别有关,且雌性含菌量高于雄性。 相似文献
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为掌握近年来赣南柑桔木虱发生动态及其携带黄龙病菌变化情况,2016-2020年,定点、定时监测了赣南10个县（区）20个正常管理果园的柑桔木虱成虫发生动态变化,并于2018年和2020年利用实时荧光定量PCR检测了赣南8个县（市）正常管理果园和失管果园柑桔木虱成虫带菌率变化。结果表明,赣南地区柑桔木虱成虫发生高峰集中在5月下旬-10月上旬,2016-2019年发生数量呈逐年下降趋势,但2020年发生量较前几年有所增加,平均虫量最高峰达93头/百梢;2020年正常管理果园和失管果园柑桔木虱带菌率均低于2018年,失管果园柑桔木虱带菌率明显高于正常管理果园;经相关回归分析,柑桔木虱带菌率与果园黄龙病发病率呈显著正相关性。 相似文献
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本文在柑橘黄龙病（Citrus Huanglongbing）及柑橘木虱起源地之一的潮汕地区,分别选择有针对虫媒的管理、无针对虫媒的管理和无管理3种防控水平的蕉柑果园。通过调查对比植株的感病率,不同虫态木虱的发生情况,黄龙病菌16SrDNA和前噬菌体的序列差异,以及柑橘木虱的种群类型。结果表明：（1）有针对虫媒管理的果园：植株发病率最低,发病等级为轻度,各虫态木虱数量最低且不带菌;无针对虫媒管理的果园中植株发病率显著提高,发病等级为轻度或中度,木虱卵和若虫的数量最多,虫媒成虫带菌率和带菌量均较低;无管理果园中植株发病率和发病等级最高,木虱成虫数量最多,虫媒带菌率和带菌量均最高;（2）植株和柑橘木虱样品中均携带黄龙病菌亚洲种Type 2原噬菌体类型,柑橘木虱均属于单一种群。 相似文献
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柑橘黄龙病（Citrus Huanglongbing,HLB）是柑橘生产上的毁灭性病害,在田间主要通过柑橘木虱（Diaphorina citri Kuwayama）传播,目前尚未有有效防治柑橘黄龙病的药剂。通过搭建防虫网室种植柑橘是目前国内多个黄龙病高发区用以防控柑橘木虱及黄龙病的新型种植方式,但有关网室栽培技术在柑橘木虱及黄龙病等主要柑橘病虫害上的防控效果并未有系统评估。本研究以黄龙病流行区（广东惠州）的柑橘果园为实验地进行防虫网覆盖,通过对网室栽培区与露天区柑橘的树势、柑橘木虱与黄龙病的流行状况及其他害虫发生情况进行系统比较,分析其差异。本研究发现,搭建防虫网室种植柑橘有利于增长其树势,一定程度上能够减少柑橘害虫的种类和数量,特别是柑橘木虱,同时黄龙病的病情也有所减轻。但网室内的相对湿度会在秋季降低,进而引起柑橘红蜘蛛（Panonychus citri McGregor）的爆发。搭建防虫网室的种植方式对柑橘生长及黄龙病的防控有重要的作用,但也会引起部分柑橘红蜘蛛和粉虱的泛滥。 相似文献
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柑桔木虱 (ＤｉａｐｈｏｒｉｎａｃｉｔｒｉＫｕｗａｙａｍａ)是为害柑桔的主要害虫之一 ,它的发生不仅对柑桔造成直接危害 ,而且 ,柑桔木虱还是传播柑桔黄龙病的媒介昆虫。因此 ,控制黄龙病的发生及蔓延 ,必须对柑桔木虱的田间发生规律进行研究 ,以便采取有效的防治措施。我们于 1996～ 2 0 0 0年在贵州省主要柑桔生产区进行了田间调查 ,并在罗甸开展了木虱室内饲养 ,并对田间消长规律进行了调查研究。柑桔木虱在贵州主要分布于南部地区海拔60 0ｍ以下 ,年活动积温在 550 0℃以上的河谷地带 ,分布于罗甸、望谟、册亨、关岭、兴义、镇宁、安… 相似文献
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本文对留草、半留草和除草等三种栽培模式柑橘果园进行一年多的有害生物（害虫和害螨）调查研究,结果表明,果园有害生物的种类有3纲8目18科25种,频度大于0.1、优势度大于0.008的有害生物均为同一样的6种类,但顺序有差异,其中柑桔木虱和红蜘蛛等属最重要害虫。除草栽培与其它栽培在害虫为害程度、为害峰期和种类稳定性等方面差异性较明显,而留草栽培与半留草栽培之间差异性小。除草栽培区生态系统脆弱,有害生物为害程度明显重,为害时间提前,其中红蜘蛛表现最典型;随着种植时间延长很可能会增加害虫种类。留草栽培和半留草栽培与除草栽培相比,能有效维持有害生物种类、为害时间和为害程度等方面相对稳定性,可有效抑制红蜘蛛暴发为害,但对柑桔木虱更有吸引力,可能导致柑橘黄龙病传播扩散速度比除草栽培区更快。三种栽培模式有害生物发生特点有一定差异性,因此实施柑橘有害生物综合治理需要“因园施策”。 相似文献
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Rassnick KM Gieger TL Williams LE Ruslander DM Northrup NC Kristal O Myers NC Moore AS 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2001,15(3):196-199
1-(2-Chloroethyl)3-cyclohexyl-1-nitrosourea (CCNU) is an alkylating agent in the nitrosourea subclass. A prospective evaluation of CCNU was done to determine the maximally tolerated dosage of CCNU in tumor-bearing cats. Response data were obtained when available. Twenty-five cats were treated with CCNU at a dosage of 50-60 mg/m3 body surface area. Complete hematologic data were available for 13 cats. Neutropenia was the acute dose-limiting toxicity. The median neutrophil count at the nadir was 1,000 cells/microL (mean, 2,433 cells/microL; range, 0-9,694 cells/microL). The time of neutrophil nadir was variable, occurring 7-28 days after treatment, and counts sometimes did not return to normal for up to 14 days after the nadir. Based on these findings, a 6-week dosing interval and weekly hematologic monitoring after the 1st treatment with CCNU are recommended. The nadir of the platelet count may occur 14-21 days after treatment. The median platelet count at the nadir was 43,500 cells/microL. No gastrointestinal, renal, or hepatic toxicities were observed after a single CCNU treatment, and additional studies to evaluate the potential for cumulative toxicity should be performed. Five cats with lymphoma and 1 cat with mast cell tumor had measurable responses to CCNU. Phase II studies to evaluate antitumor activity should be completed with a dosing regimen of 50-60 mg/m3 every 6 weeks. 相似文献
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Davis MS Willard MD Nelson SL Mandsager RE McKiernan BS Mansell JK Lehenbauer TW 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2003,17(3):311-314
Human and equine athletes are reported to have a high prevalence of gastric disease, and anecdotal evidence suggests a similar phenomenon applies to racing sled dogs. To investigate the prevalence of gastric disease in racing sled dogs, we conducted 2 gastroscopy studies on dogs competing in the annual Iditarod Sled Dog Race. A pilot study of dogs that were either dropped from the 2000 Iditarod Sled Dog Race because of illness or that finished the race indicated that, approximately 5 days after competing, 10 of 28 dogs (35%) had endoscopic evidence of gastric ulceration, erosion, or hemorrhage. The next year, an endoscopic study of 73 dogs participating in the 2001 Iditarod race was performed in order to evaluate a larger population of dogs. Data from 70 of these dogs could be used; 34 (48.5%) had ulceration, erosion, gastric hemorrhage, or some combination of these findings. When this group of 70 dogs was compared retrospectively to a control group of 87 dogs presented to the Texas A&M University (TAMU) Veterinary Medical Teaching Hospital, the Iditarod sled dogs had a significantly higher prevalence (P = .049) of gastric lesions. These findings suggest that, similar to athletes of other species, elite canine athletes have an increased prevalence of gastric disease compared to the canine population at large. 相似文献
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Furosemide continuous rate infusion in the horse: evaluation of enhanced efficacy and reduced side effects 总被引：1，自引：0，他引：1
Johansson AM Gardner SY Levine JF Papich MG LaFevers DH Fuquay LR Reagan VH Atkins CE 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2003,17(6):887-895
Continuous rate infusion (CRI) of furosemide in humans is considered superior to intermittent administration (IA). This study examined whether furosemide CRI, compared with IA, would increase diuretic efficacy with decreased fluid and electrolyte fluctuations and activation of the renin-angiotensin-aldosterone system (RAAS) in the horse. Five mares were used in a crossover-design study. During a 24-hour period, each horse received a total of 3 mg/kg furosemide by either CRI (0.12 mg/kg/h preceded by a loading dose of 0.12 mg/kg IV) or IA (1 mg/kg IV q8h). There was not a statistically significant difference in urine volume over 24 hours between methods; however, urine volume was significantly greater after CRI compared with IA during the first 8 hours ([median 25th percentile, 75th percentile]: 9.6 L [8.9, 14.4] for CRI versus 5.9 L [5.3, 6.0] for IA). CRI produced a more uniform urine flow, decreased fluctuations in plasma volume, and suppressed renal concentrating ability throughout the infusion period. Potassium, Ca, and Cl excretion was greater during CRI than IA (1,133 mmol [1.110, 1,229] versus 764 mmol [709, 904], 102.7 mmol [96.0, 117.2] versus 73.3 mmol [65.0, 73.5], and 1,776 mmol [1,657, 2.378] versus 1,596 mmol [1,457, 1,767], respectively). Elimination half-lives of furosemide were 1.35 and 0.47 hours for CRI and IA, respectively. The area under the excretion rate curve was 1,285.7 and 184.2 mL x mg/mL for CRI and IA, respectively. Furosemide CRI (0.12 mg/kg/h) for 8 hours, preceded by a loading dose (0.12 mg/kg), is recommended when profound diuresis is needed acutely in horses. 相似文献
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Waruiru RM Thamsborg SM Nansen P Kyvsgaard NC Bogh HO Munyua WK Gathuma JM 《Tropical animal health and production》2001,33(3):173-187
The epidemiology of H. placei and of other gastrointestinal nematodes in yearling dairy cattle was examined on two farms in Kiambu District, central Kenya during each of 13 one-month periods from April 1993 to April 1994. On each farm, 32 newly weaned dairy calves were given a single dose of albendazole and then placed on experimental pastures. Twelve of the animals were designated for bi-monthly slaughter (n = 2) and analysis of worm population characteristics and 20 were designated for blood and faecal collection and for weighing. Two parasite-free tracer calves were grazed alongside the weaner calves each month throughout the study period and were also slaughtered for analysis of worm populations. Faecal egg counts, haematological and serum pepsinogen determinations, herbage larval counts, and animal live weight changes were recorded monthly. The study revealed that Haemonchus placei, Trichostrongylus axei, Cooperia spp. and Oesophagostomum radiatum were responsible for parasitic gastroenteritis and that H. placei was the predominant nematode present in the young cattle on both farms. Faecal egg counts from resident cattle and necropsy worm counts revealed that pasture larval levels were directly related to the amount of rainfall. The total worm burdens in the animals were highest during the rainy season (March–June and October–December) and lowest during the dry seasons (July–September and January–February). The very low recovery of immature larvae of H. placei from the tracer calves indicated that arrested development is not a feature of the life cycle of this parasite in central Kenya. The maintenance of the parasite population depended on continuous cycling of infection between the host and the pasture. The agroclimatic conditions of the study area were such that, in general, favourable weather conditions for the development and survival of the free-living stages of gastrointestinal nematodes existed all year round. 相似文献
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The occurrence of ectoparasites in sheep flocks is frequently reported but seldom quantified. Sheep production used to be a predominantly family activity in the state of Sa~o Paulo (Brazil), but it began to become a commercial activity in the past decade. Thus, information about the ectoparasites existing in sheep flocks has become necessary. The present data were obtained by means of questionnaires sent to all sheep breeders belonging to the `Associaça~o Paulista de Criadores de Ovinos' (ASPACO; Sa~o Paulo State Association of Sheep Breeders). Response reliability was tested by means of random visits paid to 10.6% of the respondents. Most of the properties (89.5%) reported the presence of one or more ectoparasites. Screw-worm (Cochliomyia hominivorax) was the most frequent ectoparasite (72.5%), followed by bot fly larvae (Dermatobia hominis, 45.0%), ticks (Amblyomma cajennense) and Boophilus microplus, 31.3%) and finally lice (Damalinia ovis, 13.8%). Combined infestations also occurred, the most common one being screw-worm with bot fly larvae (36.0%) followed by bot fly larvae with ticks (13.9%), screw-worm with ticks (9.3%), bot fly larvae with lice (6.9%), and ticks with lice (5.0%). The most common triple combination was screw-worm, bot fly larvae and ticks (12.8%). Breeds raised for meat or wool were attacked by bot fly larvae and ticks more often than other breeds. Lice were only absent from animals of indigenous breeds. The relationships among these ectoparasites are discussed in terms of sheep breeds, flock size, seasonality and the ectoparasitic combinations on the host. 相似文献
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Evaluation of biohydrogenation rate of canola vs. soya bean seeds as unsaturated fatty acids sources for ruminants in situ 
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下载免费PDF全文 S. Pashaei T. Ghoorchi A. Yamchi 《Journal of animal physiology and animal nutrition》2016,100(2):211-216
An experiment was conducted to study disappearance of C14 to C18 fatty acids, lag times and biohydrogenation (BH) rates of C18 fatty acids of ground soya bean and canola seeds in situ. Three ruminally fistulated Dallagh sheep were used to determine ruminal BH of unsaturated fatty acids (UFAs). Differences in the disappearance of fatty acids through the bags and lag times were observed between the oilseeds. We saw that the longer the incubation time of the oilseeds in the rumen, the lower the content of C18:2 and C18:3. Significantly higher lag times for both C18:2 and C18:3 were observed in ground canola compared to ground soya bean. BH rates of C18:2 and C18:3 fatty acids in soya bean were three times higher than those of canola. These results suggest that the fatty acid profile of fat source can affect the BH of UFAs by rumen micro‐organisms. So that UFAs of canola had higher ability to escape from ruminal BH. It seems that fatty acid profile of ruminant products is more affected by canola seed compared to soya bean seed. 相似文献
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Serum biochemical values and the wet weight to dry weight ratios of tissues were determined in yaks in Shandan county of Gansu province. The liver, kidney, heart and muscle contents of seven elements in yaks were also analysed. Most serum biochemical values were similar to those of cattle, camels and sheep, but the calcium concentration was considerably above the normal range for other ruminants. The liver contained the highest concentrations of copper, manganese and cobalt and the kidney of selenium, iron and calcium.Abbreviations Alb
albumin
- ALT
alanine aminotransferase
- AST
aspartate aminotransferase
- BUN
blood urea nitrogen
- Chol
cholesterol
- Glob
globulin
- -GT
-glutamyl transpeptidase
- IP
inorganic phosphorus
- TP
total protein 相似文献
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正We are pleased to publish the second special issue on avian brood parasitism and to be responsible guest editors for the two special issues of Chinese Birds (Vol. 3, No. 4, 2012 and Vol. 4, No. 1, 2013), entitled "Avian Brood Parasitism - A Growing Research Area in Behavioral Ecology". The first issue was published in December 2012. The goal of the two special issues is to publish accumulated knowledge and some of the recent developments in 相似文献
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Tropical Animal Health and Production - 相似文献