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1.
根据川西高原栽培草地建设的生产技术需求,设播种量相同的5个播种方式(撒播、行距20或30 cm的同行或间行条播),建植燕麦(Avena sativa)和箭筈豌豆(Vicia sativa)混播草地,通过测定单株性状及生物量结构、鲜草和干草产量、干草营养成分和能量产量,研究播种方式对草地生产性能的影响。结果表明,播种方式对燕麦和箭筈豌豆的株高和分蘖数均有显著影响(P 0.05),对燕麦和箭筈豌豆密度及草地群落组成有极显著影响(P 0.01),对单株生物量及分配比有显著影响(P 0.05);撒播方式下燕麦产量最大而箭筈豌豆产量最小,30 cm间行条播下箭筈豌豆产量最大而燕麦产量最小,20 cm同行条播下草地总产量最大;30 cm间行条播下饲草营养价值最高,撒播下牧草的粗蛋白(CP)、粗脂肪(EE)、无氮浸出物(NFE)含量最低;播种方式对1 kg干物质的能量影响表现为代谢能(ME)消化能(DE)可消化养分总量(TDN)总能(GE),对草地能量产量影响表现为DE ME TDN GE。20 cm同行条播草地干草产量和能量产量最大,适合在生产中推广应用。  相似文献   

2.
通过2012~2019年对尼勒克县禁牧区温性草甸草原类草地8个样地的监测,对其牧草生长高峰期样方内的总鲜草产量、总干草产量、可食牧草鲜草产量、可食牧草干草产量及优势植物的盖度、频度及生殖枝高度进行分析,探讨尼勒克县禁牧区温性草甸草原类草地生产力变化。结果表明:2012~2019年禁牧区温性草甸草原类草地植被总鲜草产量、总干草产量、可食牧草鲜草产量、可食牧草干草产量逐年增加。2012~2019年,老鹳草、早熟禾、赖草、鸭茅的分盖度、生殖枝高度、频度有了显著提高;地榆的分盖度、生殖枝高度、频度虽有提高,但变化不显著。  相似文献   

3.
本研究旨在评定白酒糟的营养成分及在生长猪上的消化能(DE)和代谢能(ME),并基于其所含化学组分建立白酒糟在生长猪上DE和ME的预测模型。选取78头健康、体重(52.1±3.6)kg的杜×长×大三元杂交去势公猪,随机分配到1个玉米-豆粕型基础日粮和12个白酒糟(替代基础日粮供能组分的30%)待测日粮处理中进行消化代谢试验,每个处理6个重复,每个重复1头猪,用全收粪尿法和套算法测定其对生长猪的DE和ME值。进一步分析每个样品的化学成分与其有效能值的关系,用逐步回归法建立了12个白酒糟样品DE和ME的预测方程。结果表明:饲喂基础下,12个白酒糟样品的DE为3.79~8.81 MJ/kg,ME为3.54~8.15 MJ/kg;白酒槽DE的最佳预测方程为DE(MJ/kg)=38.46-0.63×粗灰分-0.11×粗纤维-1.14×总能-0.03×中性洗涤纤维(R^2=0.81),ME的最佳预测方程为ME(MJ/kg)=41.86-0.75×粗灰分-1.51×总能+0.20×粗脂肪-0.05×粗纤维(R^2=0.74)。  相似文献   

4.
对河南县天然草地高寒草甸类高山嵩草·杂类草草地型、光莩鹅观草草地型、线叶嵩草·珠芽蓼草地型、高山嵩草草地型、垂穗披碱草草地型、藏嵩草草地型、金露梅·珠芽蓼草地型等7个草地型可食混合牧草的能值、消化能、代谢能及营养成分进行分析。结果表明,7个草地型营养成分具有粗蛋白质、粗脂肪、无氮浸出物含量高和粗纤维含量低的特点。能值计算结果与生产实际相吻合。  相似文献   

5.
1粗饲料 粗饲料主要指青干草和农作物秸秆。青干草是由天然草地青草或人工栽培牧草,适时收割后经天然或人工干燥制成。青干草的营养价值与牧草种类、物候期和调制技术密切相关。青干草的粗纤维含量较高,粗蛋白质的含量随牧草种类而异,豆科牧草较高,禾本科牧草较低,能量值差异不大,豆科牧草钙的含量较高,禾本科牧草较低,优质青干草含有较多的胡萝卜素。  相似文献   

6.
对江西沟地区冬春草地围栏内外牧草地上、地下植物量的测定表明,该地区山地干草原类、山地草甸化草原类和山地草甸类三种草地类型围栏外的地上、地下植物量(鲜重)明显低于围栏内草地(P<0.05),禾本科优良牧草较围栏内分别减少4.65—18.69和7.73—28.16个百分点,而杂类草(含毒杂草)分别增加了5.92—10.95和2.61—15.28个百分点;围栏内三种草地类型优良牧草产草量和根量明显增加(P<0.05),围栏外三种草地类型由于放牧利用过重及管理差,造成优良牧草产草量和根量明显减少,表明围栏内三种草地类型正处于进展演替之中,而围栏外则处于逆行演替之中,并提出了减少围栏外草地放牧压力的建议。  相似文献   

7.
山西白羊草灌丛草地牧草产量动态研究   总被引:11,自引:0,他引:11  
董宽虎  王印魁 《中国草地》1995,(4):13-16,21
对山西白羊草灌丛草地牧草产量动态三年的定位研究结果表明,白羊草灌丛草地牧草产量的季节动态规律较稳定,各年度动态曲线均呈单峰型,高峰值出现在8月份,峰期后牧草产量下降较缓慢;牧草营养物质的变化,生长前期粗蛋白含量较高,随生育期进展而逐渐减少,粗纤维含量则相反;粗蛋白质产量高峰期在8月,这与干草产量的高峰期正好吻合,此时正是该类草地利用的最佳时期。  相似文献   

8.
陈勇 《饲料广角》2000,(2):14-15,19
能量通常用消化能(DE)、代谢能(ME)和净能(NE)三种形式表示。在NRC模型中的方程均采用DE或ME,并设定ME为DE的96%。NRC认为NE体系可能是最精确的能量体系,但在模型中选用DE和ME是由于大多数饲料无净能值项目。例如,在新版本中仅有不足一半原料的NE值是通过实验测定的,而其它原料的NE值是通  相似文献   

9.
山西白羊草灌丛草地牧草产量动态研究   总被引:4,自引:1,他引:3  
对山西白羊草灌丛草地牧草产量动态进行了研究,经3年的定位研究其结果表明,白羊草灌丛草地牧草产量的季节动态规律较稳定,各年度动态曲线均呈单峰型,高峰值出现在8月份,峰期后牧草产量下降较缓慢。牧草营养物质的变化,生长前期粗蛋白质含量高随生育期进展而逐渐减少,粗纤维含量则相反,粗蛋白质产量高峰期在8月,这与干草产量的峰值正好吻合,此时正是该类草地利用的最佳时期。  相似文献   

10.
本试验在实测消化能(DE)和代谢能(ME)的基础上,用净能(NE)预测公式预测麦麸、洗米糠、玉米、豆粕、菜籽粕、棉籽粕NE值,并用原料NE值配制饲养试验饲粮来验证测得原料NE值和推荐的生长猪NE需要量的准确性.消化代谢试验测定麦麸、洗米糠、玉米、豆粕、菜籽粕、棉籽粕的DE和ME,实测原料化学成分,选用Noblet预测N...  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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