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1.
冷地早熟禾种子生产的优化栽培技术研究   总被引:2,自引:0,他引:2  
采用3因素5水平二次回归正交组合设计试验,建立了冷地早熟种子产量(Y)与播种量(X1)、行距(X2)和施肥量(X3)的回归方程:Y=42.61+5.01X1-7.81X2+7.77X3=2.21Z1X2+1.41X1X3-0.41X2X3=4.64X1^2+6.36X2^2+8.56X3^2;并提出西宁地区冷地早熟禾种子生产的优化农艺措施,播咎量8kg/hm^2,播种行距20-30cm,种肥150  相似文献   

2.
“利用荒漠和盐碱地建立人工草地的研究”总结报告   总被引:1,自引:1,他引:0  
课题在柴达木盆地实施,4年的研究结果:①碱茅是利用盐渍地建立人工草地的首选牧草,可在中一重度含盐量(0.5%~1.47%)的土壤上生长,种植第三年产青于草4500kg/hm^2;②在荒漠地区采用围栏封育2年产量比对照提高3.91倍,封育+灌溉提高4.29倍,灌溉+补播+封育提高1.42~6.2倍;③用沙棘、小红柳、绵柳建立物围栏5KM,成活率分别为76%,96.8%和94%;④以单位面积粗蛋白产量  相似文献   

3.
黄河故道沙荒草地生物量及营养价值特性研究   总被引:3,自引:0,他引:3  
对黄河故道沙荒草地生物量季节变化规律以及牧草营养物质出动态进行了分析,结果表明:(1)沙荒草地牧草生物量的增长呈二次曲线变化规律:y=1/(3.79×10^-7t^2-9.32×10^-5t+7.83×10^-3),并且其生物量在9月份达到最大值;(2)从5月份开始沙荒草地牧草营养价值逐渐降低,且于物质消化率(DMD)与其粗蛋白质(CP),木质素(LIG)含量分别表现为显著正相关(r=0.94)和  相似文献   

4.
利用荒漠和盐碱地建立人工草地的效益分析   总被引:4,自引:1,他引:3  
1991~1992年,在海西州德令哈市利用荒漠建立半人工草地86.1hm^2,利用盐碱弃耕地建立人工草地74.6hm^2,取得了明显的生态、社会和经济效益,建植第三年的沙打旺人工草地植被盖度由原来的15%提高至70%~80%,耕层(0-30cm)总盐平均含量由原来的9.3g.kg^-1,下降1.23g.kg^-1,脱盐率达86.26%,在受益期内,160.7hm^2人工、半人工草地可新增牧草360  相似文献   

5.
蛋鸡饲喂稀土饲料添加剂的效果   总被引:1,自引:1,他引:0  
1995年11月到1996年7月在平安县种鸡场对罗曼商品代蛋鸡进行234d饲喂稀土试验。试验设4个组,每组295只。试验1,2,3组鸡日粮中分别添加0.01%、0.015%和0.02%的RCT-3有机稀土饲料添加剂,对照组鸡不喂稀土。结果:试验1,2,3组母鸡日产蛋总重比对照组鸡分别提高13.91%(P<0.01),8.36%(P<0.05)和0.97%(P>0.05);产蛋率分别提高9.59,5.72和0.83百分点;只均纯收入增加8.52元,5.01元和0.21元。  相似文献   

6.
NH565型方草捆捡拾打捆机引进使用效果分析   总被引:3,自引:1,他引:2  
刘兴元 《草业科学》1995,12(6):57-60
本文对NH565型方草捆捡拾打捆机的机械性能,应用效果以及经济效益进行了研究。通过3年的中间生产试验,结果表明,该机具有使用的可靠性达95%以上,成捆率为86.5%,草捆密度可达174.6kg/m^3,牧草损失率为8%~10%,经济效益显著,利用成本原理进行盈亏分析,年作业量只要达到32.3hm^2,即可盈亏平衡,通过对机具敏感度分析,表明机具的每公顷收费标准,使用寿命和年利用率是影响经济效益的主  相似文献   

7.
高寒地区牧草引种栽培试验研究   总被引:17,自引:4,他引:13  
本试验于1993年在青海省晏牧场进行,共引25种优良耐寒2抗旱牧草品种。通过一年的研究,间比淘汰、筛选出3种豆科牧草,5种本科牧草。其中,禾本科草产干草4667.75kg/hm^2,豆科牧草干草产量1200kg/hm^2。经营养成分分析,8种牧草的营养成分、适口性均高于当地栽培的燕麦品种,而燕麦品种高于天然草场牧草品种。  相似文献   

8.
1手术过程1.1术前虫体寄生部位的确定可根据临床表现,确定虫体寄生部位。1.2有效手术区域及中心区定位在两眶上孔后1.5cm处作连线(间距为5cm)作为脑室的前壁起点,向后8cm与顶间骨后缘凹陷处(作为大脑室的后壁)形成8×5cm的长方形有效手术区域。有效区域中心部位,骨厚度最薄为3.5~4.5mm,但无角羊与有角羊有所区别。1.2.1无角绵羊定位:有效手术区域前后壁骨厚均为7~8mm,中心区(5×5cm)厚度为3.5~4.5mm,选择中心区为手术通路最理想。1.2.2有角绵羊定位:由于有角羊常顶架头骨易变形,…  相似文献   

9.
本试验测定了母鸭免疫后不同时期所产雏鸭的母源抗体及其卵黄吸收情况。结果表明:(1)1~4周龄雏鸭血清中均含母源抗体,在1~3周内可获得不同程度保护。5~8d为母抗高峰期,保护率100%(6/6),3~4d和10~14d的保护率83.3%(5/6),20d后保护率不到50%。(2)同居感染结果,5日龄保护80%(4/5),10日龄保护40%(2/5),15日龄20%(1/5),20,25日龄均无存活。(3)正常情况(脐带收得好)下,出壳72h卵黄吸收率达84.8%,120h吸收率95.1%,172h几乎全部(98.9%)吸收。  相似文献   

10.
对鸡新城疫病毒(NDV)中等毒力毒株CS2株、NDⅠ系、Rokin、Komerov和低毒力LaSota株病毒的脑内致病指数(ICPI)、鸡胚的半数感染量(EID50)等指标进行了测定,结果是ICPI分别为1.27~1.52、1.66~1.70、1.46、1.43和0.29~0.5;EID50分别为10^7.5、10^7.5≥10^8.5、10^^7.9和≥10^8.5/0.1ml。用10倍剂量的CS2株病毒注射1月龄和1.5月龄SPE雏鸡,均安全无不良反应,测定CS2株病毒保存期,结果在-20℃保存6年的鸡胚2代(E2)、鸡胚6代(E6)、鸡胚10代(E10)毒的EID50均≥10^7.5/0.1ml。NDCS2株病毒的各项指标均在中等毒力范围内,对鸡胚的半数感染量仍保持原毒(Ⅰ系)的特性,ICPI比原毒有所下  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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