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1.
不同温湿度对草地螟白僵菌的致病力影响   总被引:1,自引:0,他引:1  
测试了不同温、湿度下白僵菌(Beauveria bassiana)对草地螟(Loxostege sticticalis)幼虫的致病力。实验设置了17、20、23、26、29℃5个温度水平,相对湿度(95±5)%、(85±5)%、(75±5)%、(65±5)%和(55±5)%5个梯度,用浓度为1×109孢子/mL的白僵菌孢子液感染2龄的草地螟幼虫。结果表明:在温度为26℃时的致死中时(LT50)最短,死亡速度最快,死亡率最高;高于或低于此温度时,草地螟幼虫的LT50延长,死亡速度减慢。相对湿度发生变化时,草地螟幼虫死亡速度和死亡率不同。相对湿度为95%时,棉铃虫死亡速度最快,死亡率最高;相对湿度低于55%时,棉铃虫死亡率显著降低。相对湿度越高,草地螟幼虫死亡速度越快。  相似文献   

2.
蜂王幼虫的生长发育会受到遗传、生长环境、营养物质等因素的影响.工蜂直接饲喂蜂王浆是影响蜂王个体发育的重要因素之一.在蜂王幼虫期发育过程中,工蜂供给的食物是蜂王浆,观测发现:不同日龄的幼虫王台内的蜂王浆量变化不同.在幼虫期的0~60h,1日龄幼虫王台内的蜂王浆量比2日龄幼虫少;60~84h时,情况相反.  相似文献   

3.
通过对桑螟越冬老熟幼虫控温试验和第6代桑螟不同温度下的生长发育状况的观察得知:桑螟越冬是休眼性越冬,在20℃、25℃和30℃下,越冬老熟幼虫可迅速恢复正常发育,化蛹和羽化,而且以25℃为最适发育温度;在条件适宜时第6代桑螟老熟幼虫可不越冬,继续发育,完成世代;在自然条件下,当气温下降至16℃以下,未越冬的幼虫均停止生长发育而逐渐死亡,翌年春季气温回升到16℃以上,越冬老熟幼虫结束休眠而化蛹。  相似文献   

4.
为了解育种过程中不同条件对滇南中蜂蜂王初生重的影响,优化滇南中蜂蜂王的选育方法,试验比较了蜂群内自然繁殖的蜂王与人工培育的蜂王的出生率和初生重。结果表明:不同组间幼虫成活率相同时,蜂王的出生率无明显差异;自然蜂王的初生重为(0.159 1±0.020 3)g,人工蜂王的初生重为(0.126 1±0.008 7)g,自然蜂王的初生重与人工蜂王的初生重相比高26%,且差异显著(P0.05)。  相似文献   

5.
采用正交实验法,以蜂王幼虫保鲜天数为指标,探究蜂王幼虫保鲜液的最佳配比。结果表明:当蜂胶提取物含量为0.2%、乙醇浓度为95%时,对蜂王幼虫的保鲜效果最佳;该条件下可使蜂王幼虫维持一级保鲜度(挥发性盐基氮VBN值≤150 mg/kg-1)的理论保鲜天数达8.85 d。该保鲜液配制容易,对蜂王幼虫产品的开发有一定的促进作用。  相似文献   

6.
以蜂胶提取物(Propolis)、柠檬酸(Citric acid)、乙醇(Alcohol)为主要成分,研制蜂王幼虫保鲜液;采用正交实验设计法探究蜂胶提取物、柠檬酸、乙醇三个因素的最佳配比。实验结果表明,此蜂王幼虫保鲜液的最佳配比为:乙醇75%、蜂胶提取物0.15%、柠檬酸0.75%;在此条件下,蜂王幼虫在30℃,湿度80%的环境下可以保鲜9.90 d,蜂王幼虫虫体的挥发性盐基氮值(TVB-N)仍然小于150 mg/kg,保持一级新鲜度。该天数基本可以满足蜂王幼虫从生产到加工环节的需要。  相似文献   

7.
蜂王幼虫又称蜂王胎、蜂皇胎,是蜜蜂受精印经工蜂喂饲新鲜王浆生长发育的幼虫体,是从王台里采集的幼虫。蜂王幼虫以蜂王浆为食,幼虫本身有极丰富的营养,同时体表也粘附着蜂王浆,它是人工生产蜂王浆的副产品。  相似文献   

8.
蜂王浆与性激素史红梅,史伯伦蜂王浆是青年工蜂的王浆腺分泌物,用来饲喂蜂王和蜂王幼虫。蜂王幼虫相当于哺乳动物“胎儿”,胎儿时期的生长速度是动物一生中生长发育最快的阶段。而蜂王幼虫食用蜂王浆之后生长发育尤其突出,五天之内增长1800倍。这样高速增长的能源...  相似文献   

9.
维生素E对中华蜜蜂蜂王发育的影响   总被引:1,自引:0,他引:1  
以中华蜜蜂姐pisce僦cerosa)为试验材料,在培育中华蜜蜂蜂王的过程中,分别添加4种不同剂量的维生素E溶剂,检测其对中华蜜蜂处女蜂王初生重和卵巢重的影响。结果表明:添加不同剂量维生素E对蜂王初生重没有影响,差异不显著;过高剂量地补充维生素E会降低处女王的卵巢重,不利于蜂王幼虫的生长发育。  相似文献   

10.
三、幼虫的营养蜂王幼虫的营养——蜂王幼虫培养在特殊的巢房内即王台内。在整个蜂王幼虫时期都得食丰富的王浆。甚至在王台封盖以后,她们还有食物可吃。哺育蜂饲喂蜂王幼虫所采用的两个类型的分泌物,即清水状分泌物和白色不透明的乳状分泌物;前者由平均17±2日龄的哺育蜂所分泌的,而后者由平均12±2日龄的哺育蜂所分泌的。这些分泌物  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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