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1.
天山北坡草地蝗虫群落的数量分类与排序   总被引:2,自引:0,他引:2  
李新华 《草业科学》1993,10(2):66-69
文章对天山北坡紫泥泉地区不同草地类型上的蝗虫群落结构和排序分类进行了研究,结果表明,该地区蝗虫的群落结构与草地类型是密切相关的,蝗虫群落可分为:(1)荒漠类蝗虫群落(2)草原类蝗虫群落(3)草甸类蝗虫群落,三个大类。  相似文献   

2.
本文通过对呼伦贝尔市不同草地类型中分布的蝗虫种类、密度进行了调查,研究探索了分布特点,并对不同草地类型中蝗虫种类组成相似性进行了等级聚类分析。结果表明:在温性典型草原类的高平原干草原亚类草地中分布的蝗虫种类最多,达38种,占全部种类的65.5%,平均密度为38.8头/m2;温性草甸草原类的山地草甸草原亚类草地中分布的蝗虫种数位居第2,有32种,占全部种类的56.9%,平均密度为36.1头/m2;沼泽类草地类型中分布的蝗虫种类最少,7种,占全部种类的12.0%,密度〈5头/m2。蝗虫种类分布概况,经对不同草地类型进行等级聚类分析,其结果体现出不同草地之间的差异性,为进一步论证草地蝗虫与草地生境之间有着密切的关联提供了科学的理论依据。  相似文献   

3.
肃南县草地蝗虫发生及防治对策   总被引:2,自引:0,他引:2  
本文报道了肃南县草地蝗虫的发生现状,不同草地类型群落的组成,发生数量和危害程度,并提出了药物防治的方法和效果,分析了发生的原因,提出了今后草地蝗虫的防治对策和草地管理的建议。  相似文献   

4.
本文对阿鲁科尔沁旗3个主要草地类型蝗虫发育期土壤温度、土壤含水量,蝗虫孵化出土日期和虫龄发育动态,虫口密度动态,各类型草地蝗虫种类构成进行了初步调查研究。结果表明,蝗虫种类达15种,不同草地类型蝗虫种类不同;在土壤温度达到22℃以上,含水量达到5.4%RH以上时是草地蝗虫孵化盛期;根据各类型草地蝗虫虫龄发育情况和虫口密度变化规律,确定阿鲁科尔沁旗蝗虫最佳防治时间为7月9日~8月12日。  相似文献   

5.
萨仁高娃 《青海草业》2010,19(2):39-40,44
海北州是草地蝗虫灾害频发的地区之一,每年的蝗虫危害面积广、密度高、危害严重。本文从蝗虫的发生数量、危害程度、损失状况等方面进行了详细的调查,并结合实际,对草原蝗虫的生态学特性进行了分析研究,为今后更好的开展草地虫害监测、提高预测预报准确率提供了依据。  相似文献   

6.
蝗虫是天然草原生态系统中的重要组成部分,了解草原生态系统中蝗虫群落的结构及多样性是揭示草原蝗虫成灾危害机制及其可持续治理的基础工作之一。近年来,国内对草地昆虫群落结构进行了部分研究工作,但对不同植被类型蝗虫群落结构组成及多样性方面的研究少。  相似文献   

7.
草地蝗虫的营养价值   总被引:1,自引:0,他引:1  
秦丽萍  刘志云  孙涛 《草业科学》2013,30(1):141-147
草地蝗虫是一种高蛋白、低脂肪、富含维生素和矿物元素的天然优质可食用、药用和饲用资源,但大量爆发会造成草地植被退化,对草地造成一定的危害。充分了解蝗虫体内营养物质及其变化规律,对其进行合理利用,不仅可以减少蝗虫对草地的危害,还能有效缓解食品、饲料和医药行业的资源危机。本文对草地蝗虫的蛋白质、脂质、矿质元素、维生素和黄酮类物质等营养成分进行总结,并且对其动态变化和开发利用进行分析,以期为更加合理和高效地利用草地蝗虫资源提供参考。  相似文献   

8.
蝗虫对赤峰市草地造成较大危害,其发生有自然因素和人为因素。在掌握草地蝗虫发生和分布的情况下,应采取以下治理策略(1)加强草地管理,合理利用草地资源;(2)加强对主要蝗虫种群的监控;(3)保护和利用天敌资源;(4)进行综合防治,具体包括草地改良、物理方法、生物防治和化学防治。  相似文献   

9.
草地蝗虫是危害草原的毁灭性害虫,它食性杂、分布广、迁移迅速,被称为农牧业生产四大灾害之一。近年来,草地蝗虫对草原的危害日趋严重,每年危害面积达1.5亿万亩以上,导致草原大面积退化,产草量下降,严重制约着我国畜牧业发展。及时、准确地进行草地蝗虫发生情况的监测预警,对牧区畜牧业健康发展、地区经济可持续发展以及社会安定都有重要意义。[第一段]  相似文献   

10.
本文介绍了甘肃省肃南县草地蝗虫的现状,分析了不同草地类型的蝗虫种类分布,提出了相应的治理措施,为加强草地管理与建设,改善草地生态环境提供决策依据。  相似文献   

11.
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   

12.
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   

13.
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   

14.
15.
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   

16.
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   

17.
Our particular attention in this article was given to natural mediators for macrophages isolated from the sites of tissue injury. A number of chemotactic factors, which may satisfy many criteria making them acceptable as inflammatory leucocyte chemotactic factors, has been separated. Among them, our laboratory has isolated three macrophage (monocyte) chemotactic factors (MCF-a, -b and -c). Their purification, characterization and functional specificity are discussed.  相似文献   

18.
19.
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   

20.
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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