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1.
干旱地区华北驼绒藜育苗移栽是提高建植成活率的有效途径.利用生根粉、保水剂及清水浸泡及剪根等处理,对不同株龄和移栽不同时期的华北驼绒藜成活率进行了对比试验研究.结果表明,春季移栽成活率为72.6%,秋季为90.3%,药剂处理能够有效提高成活率.  相似文献   

2.
华北驼绒藜育苗移栽技术研究   总被引:3,自引:0,他引:3  
干旱地区华北驼绒藜育苗移栽是提高建植成活率的有效途径。本文利用生根粉、保水剂及清水浸泡及剪根等处理,对不同株龄和移栽的不同时期的成活率进行了对比试验研究。结果表明,春季移栽成活率为72.6%,秋季为90.3%,药剂处理能够有效提高成活率。  相似文献   

3.
为合理利用荒漠草原区饲草资源,开展了分别以华北驼绒藜、紫花苜蓿为主要饲草配合谷草、冰草饲喂苏尼特羔羊的试验。根据组合效应原理科学组合.试验共设100%华北驼绒藜、50%华北驼绒藜+50%谷草、50%华北驼绒藜+50%冰草、100%苜蓿、50%苜蓿+50%谷草、50%苜蓿+50%冰草6个处理。结果表明,100%苜蓿处理的羔羊增重、屠宰率、净肉率都明显高于其他饲草处理,其饲喂效果最好。不同饲草组合饲喂效果为:50%华北驼绒藜+50%谷草〉100%华北驼绒藜、50%华北驼绒藜+50%冰草;100%苜蓿〉50%苜蓿+50%谷草、50%苜蓿+50%冰草。  相似文献   

4.
为合理利用荒漠草原区饲草资源,开展了分别以华北驼绒藜、紫花苜蓿为主要饲草配合谷草、冰草饲喂苏尼特羔羊的试验.根据组合效应原理科学组合,试验共设100%华北驼绒藜、50%华北驼绒藜+50%谷草、50%华北驼绒藜+50%冰草、100%苜蓿、50%苜蓿+50%谷草、50%苜蓿+50%冰草6个处理.结果表明,100%苜蓿处理的羔羊增重、屠宰率、净肉率都明显高于其他饲草处理,其饲喂效果最好.不同饲草组合饲喂效果为:50%华北驼绒藜+50%谷草>100%华北驼绒藜、50%华北驼绒藜+50%冰草;100%苜蓿>50%苜蓿+50%谷草、50%苜蓿+50%冰草.  相似文献   

5.
NaCl胁迫下苞片对华北驼绒藜种子萌发的影响   总被引:5,自引:2,他引:3  
对去苞片和带苞片的华北驼绒藜种子在不同的盐浓度下进行处理,带苞片种子的发芽率、发芽指数、活力指数均高于去苞片的。在NaCl浓度为70,140,210,280和420mmol/L 时,带苞片种子的发芽率显著高于去苞片的(犘<0.05),分别为90.00%,89.00%,79.75%,69.25%,53.75% 和78.50%,81.50%,74.00%,62.25% 和39.25%。用蒸馏水和490mmol/L 的NaCl溶液对带苞片和去苞片的华北驼绒藜的种子处理12h,带苞片种子吸水率均低于去苞片的,苞片延缓了种子的吸水率。490 mmol/L NaCl处理华北驼绒藜种子1,3 和7d后,苞片中Na+ 含量显著增加(犘<0.05)。说明华北驼绒藜种子的苞片可以吸附一部分Na+ ,减少对胚的伤害。苞片对华北驼绒藜在荒漠盐渍环境中的定植具有重要的意义。  相似文献   

6.
华北驼绒藜是一种数量可观、广泛分布于我国荒漠草原区的饲草资源,但目前人们对其饲用价值的认识还停留在传统水平。为了充分了解和更好地利用华北驼绒藜这一自然资源,缓解冬春季及“白黑灾害”造成的饲草不足问题。更好地为荒漠草原区探索出高效养羊的新路子,开展了华北驼绒藜饲用评价试验。将华北驼绒藜、谷草、苜蓿铡短、粉碎后,再与50%、30%、20%的精料混合制成颗粒日粮,饲喂绵羊,通过比较不同处理组绵羊的增重情况,结合经济效益分析,评价不同精粗比水平下华北驼绒藜的养羊效益。试验表明,华北驼绒藜和谷草在30%精料水平下。具有与相同精料水平下用苜蓿饲喂绵羊同等的增重效果,并可增加纯收入高于80元/只;华北驼绒藜在精粗比为3:7的条件下有较好的养羊经济效益。  相似文献   

7.
管理方式对华北驼绒藜生长及种子产量、质量的影响   总被引:2,自引:0,他引:2  
王学敏  易津  张鹏 《草地学报》2003,11(2):139-145
研究施肥、浇水等不同管理措施对华北驼绒藜生长及种子产量、质量的影响。结果表明,适宜的田间管理可以提高华北驼绒藜的株高、枝条数、种子产量和质量。其中3次施肥+喷钾增产增质效果优于其它处理。3次施肥为最佳施肥方式。浇水及喷施钾肥对促进华北驼绒藜营养生长和提高种子产量、质量没有明显的作用。  相似文献   

8.
华北驼绒藜是一种数量可观、广泛分布于我国荒漠草原区的饲草资源,但目前人们对其饲用价值的认识还停留在传统水平,为了充分了解和更好地利用华北驼绒藜这一自然资源,缓解冬春季及“白黑灾害”造成的饲草不足问题,更好地为荒漠草原区探索出高效养羊的新路子,开展了华北驼绒藜饲用评价试验.将华北驼绒藜、谷草、苜蓿铡短、粉碎后,再与50%、30%、20%的精料混合制成颗粒日粮,饲喂绵羊,通过比较不同处理组绵羊的增重情况,结合经济效益分析,评价不同精粗比水平下华北驼绒藜的养羊效益.试验表明,华北驼绒藜和谷草在30%精料水平下,具有与相同精料水平下用苜蓿饲喂绵羊同等的增重效果,并可增加纯收入高于80元/只;华北驼绒藜在精粗比为3:7的条件下有较好的养羊经济效益.  相似文献   

9.
华北驼绒藜雨季移栽成活率研究   总被引:1,自引:0,他引:1  
本文是不同季节移栽华北驼绒藜(Ceratoides arborescens)系列研究之一。干旱区春季生态建植有补水之苦,雨季移栽表明,不需坐水或补水,成活率可高达60%,浸根可提高成活率至90%;说明雨季移栽是可行的。移栽植株数日内叶片含水量和叶绿素含量急剧下降、脯氨酸含量骤然升高,含量恢复过程则较缓慢,说明移栽使植株突然损伤,但终能恢复至正常生理状态。  相似文献   

10.
对华北驼绒藜、驼绒藜和内蒙古驼绒藜染色体进行了研究。结果表明,3个种的染色体基数均为9,华北驼绒藜为二倍体,驼绒藜为四倍体,内蒙古驼绒藜为六倍体。这3种植物即使在同种植物内常因产地不同其核型也有差异。  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.
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   

13.
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   

14.
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   

15.
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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17.
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   

18.
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   

19.
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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