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1.
复合菌肥与化肥配施对高寒地区土壤微生物数量和土壤酶活性的影响 总被引：2，自引：0，他引：2
以种植第3年的金皇后紫花苜蓿为材料,以不施肥为对照,研究了固氮菌肥、磷肥、混合菌肥及磷肥与混合菌肥不同比例配施对高寒区土壤微生物数量和土壤酶活性的影响。结果表明:不同比例配施处理后,0~10、10~20cm土层中土壤微生物(细菌、放线菌、真菌)总数、脲酶、蔗糖酶、蛋白酶活性均增加。土壤3大类微生物数量均表现为细菌放线菌真菌。0~10cm土层中的微生物数量均高于10~20cm土层中的数量。不同比例的磷肥与混合菌肥配施后的细菌、放线菌数量高于单施磷肥或混合菌肥后的数量,配施后各土层的细菌数量与对照和单施磷肥或混合菌肥后的数量之间有着显著差异。施加50%磷肥+混合菌肥后细菌、真菌数量最多。0~10cm土层中的脲酶、蔗糖酶、碱性磷酸酶和蛋白酶高于10~20cm土层中的酶活力,但10~20cm土层中的过氧化氢酶活力高于0~10cm土层中的酶活力。不同比例的磷肥与混合菌肥配施后的脲酶活力高于单施磷肥或混合菌肥后的酶活力。相关性研究表明,施肥后各土层土壤微生物与土壤酶之间存在不同程度的相关性。 相似文献
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根据植被数据将民勤荒漠绿洲过渡带12个退化人工梭梭林样点采用聚类分析的方法划分为4个退化程度,研究了不同退化程度人工梭梭林对土壤理化性质与生物学特性的影响,结果表明,1)人工梭梭林退化对土壤容重、全盐含量与阳离子代换量影响不显著,对有机质与pH影响显著;随着土层深度增加以及退化程度加剧,有机质含量降低,pH值变化复杂。2)三类微生物数量与微生物总数总体随着土层深度增加而降低,0~5 cm土层中细菌数量占极大优势,其他土层上细菌数量与放线菌数量相当,各土层中真菌数量极少。随着退化程度的加剧,真菌数量无明显变化;0~5 cm与5~10 cm土层的细菌数量、放线菌数量与微生物总数均显著减少,10~20 cm土层无显著变化;0~5 cm土层细菌和放线菌比例变化复杂,而其他土层无显著变化。3)4种酶的活性总体上随土层加深而降低,0~5 cm土层酶活性随退化程度加剧而降低,而5~10 cm与10~20 cm土层无显著变化。人工梭梭林退化对土壤过氧化氢酶、脲酶与蛋白酶活性的影响大于对蔗糖酶活性的影响,过氧化氢酶、脲酶与蛋白酶的敏感性强于蔗糖酶。4)土壤理化性质、微生物数量以及酶活性间相关性总体较强,但理化性质间相关性较弱,容重、放线菌数量同其他指标相关性较弱。退化人工梭梭林的土壤肥力、生物学性质等已经发生衰减,其恢复需要土壤的综合改良。 相似文献
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《草原与草坪》2020,(3)
以甘肃敦煌盐碱地为研究对象,在分布黑果枸杞,骆驼刺以及黑果枸杞和骆驼刺混生植被的盐碱地上选取0～20、20～40和40～60 cm土层,测定土壤理化性质、土壤酶活性、土壤微生物群落数量。结果表明:不同植被条件下土壤中Cl~-含量随着土层深度增加而减少,且集中在土壤0～20 cm;电导率随着土层深度增加而减小;阴离子中Cl~-含量大于SO_4~(2-),阳离子中Na~+含量最大。不同植被和不同土层中细菌数量最多,真菌数量最少,放线菌数量介于细菌和真菌之间。土壤中过氧化氢酶、转化酶及碱性磷酸酶活性差异显著(P<0.05),而脲酶活性差异不显著(P<0.05)。综合分析表明该区域盐碱地土壤盐以NaCl为主,土壤微生物中细菌数量最多。 相似文献
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《草业学报》2020,(2)
为了探讨不同耕作和覆盖方式对陇东黄土旱塬农田耕层土壤养分、土壤容重、酶活性及微生物数量的影响。采用随机区组设计,设置留膜留茬免耕栽培(T)和全膜双垄沟播栽培(CK)2个处理,测定不同生育时期0～10 cm、10～20 cm、20～40 cm 3个土层土壤养分含量、水解酶(蔗糖酶、脲酶、磷酸酶、过氧化氢酶)活性及微生物(细菌、放线菌、真菌)数量等指标。结果表明:与CK相比,留膜留茬免耕栽培显著(P0.05)提高了收获期表层(0～10 cm)土壤有机质、全量磷钾及速效磷钾含量,随土层深度增加,有机质及全量和速效磷钾含量均呈递减趋势。碱解氮含量在0～20 cm土层降低,在20～40 cm土层出现聚集。留膜留茬免耕栽培显著(P0.05)增加了0～10 cm、10～20 cm、20～30 cm土层土壤容重,增幅为7.1%～12.4%。不同耕作方式玉米0～40 cm土层微生物数量为细菌放线菌真菌。耕作方式对不同土层各生育期土壤微生物数量整体上影响显著(P0.05),为TCK。同一生育期随土层深度增加,土壤微生物数量整体上呈减少趋势,以表层(0～10 cm)最高,为TCK。与CK相比,T的细菌和真菌在苗期、拔节期、抽雄期、灌浆期、收获期分别增加23.7%、64.5%、7.6%、44.0%、5.6%和31.1%、91.7%、85.7%、10.5%、33.3%。放线菌在苗期、拔节期、收获期分别增加79.8%、15.1%、17.6%,抽雄期、灌浆期分别减少17.2%、33.2%。耕作方式对不同土层各生育期土壤酶活性整体上影响显著(P0.05),为TCK。同一生育期随土层深度增加,酶活性逐渐降低,以表层(0～10 cm)最高,T效果优于CK,与CK相比,T的蔗糖酶、脲酶、磷酸酶、过氧化氢酶在玉米全生育期增幅分别为4.7%～126.1%、9.8%～47.0%、5.4%～33.7%、2.3%～43.2%。相关分析表明:土壤酶活性之间呈显著(P0.05)或极显著(P0.01)相关,细菌与蔗糖酶显著(P0.05)相关,与磷酸酶极显著(P0.01)相关,放线菌与土壤酶活性呈显著(P0.05)或极显著(P0.01)相关,表明土壤微生物数量与酶活性能较好地反映土壤肥力水平。因此,留膜留茬免耕栽培在旱作农田条件下有利于土壤有机质及磷钾养分含量、酶活性及微生物数量的提高。 相似文献
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林芝地区不同草地土壤微生物区系分析 总被引：1，自引：0，他引：1
通过对林芝地区3种不同类型草地（高寒草甸草地、沼泽草地和栽培草地）土壤微生物进行研究,利用稀释平板法对3种草地土壤中的细菌、真菌和放线菌进行分离。结果显示,该地区不同草地中的微生物均以细菌占优势,占微生物总数的91.2%以上,放线菌数量最少,仅占3.79%。不同类型草地微生物总数有明显差异,栽培草地>沼泽草地>高寒草甸草地;同一类型草地不同土层深度垂直动态明显,0～10 cm土层数量较多,且与10～20 cm土层微生物数量有显著差异。不同草地土壤含水量差异较大,低湿条件有利于放线菌的生长,但不利于真菌的生长。 相似文献
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本文对省内部分桑园土壤分0~20、20~40cm两个土层,应用比色法测定其脲酶活性及氨含量,并用选择培养基法检测了土壤中细菌、放线菌、真菌三大类微生物的含量。结果表明各地桑园土壤中脲酶活性和微生物含量存在较大差异。在所检测的土样中,吴江松陵桑园土样脲酶活性最高,而射阳特庸桑园土壤脲酶活性最低。另外,脲酶活性与微生物含量及土壤氨含量有关。 相似文献
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采用随机区组设计,设4个单播鸭茅、无芒雀麦(Bromus inermis)、白三叶(Trifolium repens)、苜蓿(Medicago sativa)、15个混播处理(9∶1、7∶3、5∶5、3∶7、1∶9)和无牧草播种处理,研究鸭茅与伴生种在不同混播比例下对土壤微生物数量和土壤酶活性的分布影响。结果表明:土壤微生物数量和土壤酶活性随着土层深度的增加而逐渐降低,且表现为0~10 cm10~20 cm。混播处理相同土层,土壤细菌和放线菌以鸭茅和苜蓿混播时为最多,鸭茅和无芒雀麦混播时次之,鸭茅和白三叶混播时最小。鸭茅和豆科牧草混播时的脲酶活性高于鸭茅和无芒雀麦混播时的活性,鸭茅和苜蓿或无芒雀麦混播时的土壤蔗糖酶和土壤过氧化氢酶高于鸭茅同白三叶混播时的活性。与无牧草播种处理相比,单播和混播处理均提高了土壤蔗糖酶和过氧化氢酶活性。 相似文献
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不同土壤管理方式对梨园土壤养分、酶活性及果实风味品质的影响 总被引：5，自引：0，他引：5
为探讨不同土壤管理方式对梨园土壤养分、酶活性及梨果实风味品质的影响,研究了行间自然生草、菌渣覆盖和对照清耕处理对梨园土壤矿质营养、微生物种类和数量、土壤酶活性及鸭梨果实风味品质的影响。结果表明,行间自然生草、菌渣覆盖处理均使梨园有机质含量显著上升,自然生草处理3年后0~20 cm土层有机质含量达到15.05 g/kg,为清耕处理的1.9倍,土壤表层 (0~20 cm) 和亚表层(20~40 cm) 的碱解氮、有效硼和有效锌含量均显著高于对照,而有效K、有效Ca、Mg、Fe的含量低于对照。覆盖处理3年后0~20 cm土层有机质含量为19.54 g/kg,是清耕处理的2.4倍,土壤表层 (0~20 cm)和亚表层(20~40 cm) 的碱解氮、有效磷、有效钾、有效钙、镁、铁和有效硼及有效锌均高于对照。自然生草、菌渣覆盖处理使土壤微生物数量和酶活性提高,自然生草处理3年后0~20 cm土层细菌、真菌和放线菌数量分别比对照提高163.40%,18.75%,166.24%,菌渣覆盖处理3年梨园0~20 cm 表层土壤细菌、真菌、放线菌数量分别较清耕梨园提高402.33%, 37.50% 和163.05%,磷酸酶活性分别是清耕梨园的1.45和2.00倍,脲酶活性分别是清耕梨园的1.94和2.39倍。生草、菌渣覆盖处理使果实风味品质显著提升,果实香气物质种类和含量显著高于对照清耕处理,糖含量也明显升高。 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
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
20.
Tropical Animal Health and Production - 相似文献