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121.
为探究秋海棠的优良栽培基质及草坪草的修剪废弃物替代泥炭作为基质的可能性,以栽培广泛的四季秋海棠幼苗为试材,在上海辰山植物园的栽培大棚中进行盆栽试验.分别选用T1(泥炭∶珍珠岩=1∶1)、T2(泥炭∶珍珠岩∶松树皮=1∶1∶1)、T3(玉米秆∶珍珠岩∶松树皮=1∶1∶1)、T4(玉米秆∶珍珠岩∶松树皮=2∶1∶1)、T5(草秆∶珍珠岩∶松树皮=1∶1∶1)、T6(草秆∶珍珠岩∶松树皮=2∶1∶1)、T7(蛭石∶珍珠岩∶松树皮=11∶1)和T8(蛭石∶珍珠岩∶松树皮=2∶1∶1)8种混合基质,比较四季秋海棠的生长表现差异.结果表明,四季秋海棠在8种栽培基质中,上盆后30~60 d时茎均显著增大,60~90 d时株高、叶数和叶面积增加最多.最佳综合表现为T6处理,在该基质中,分枝数、叶片厚度、开花数、地上部分鲜干质量和相对叶绿素含量均最大.综合评价分析,基质用草秆∶珍珠岩∶松树皮=2∶1∶1替换泥炭,可满足四季秋海棠生长,因此,修剪后的草坪草废弃物可替换泥炭用于秋海棠的无土栽培基质.  相似文献   
122.
Hay samples from 29 horse farms in Southern Upper Bavaria and 31 horse farms in Switzerland were taken and analysed for minerals such as calcium, magnesium, phosphorus and potassium. The content of herbs and legumes in the hay was determined and the Weende analysis was performed. Comparison between Bavaria and Switzerland resulted in comparable calcium contents of approximately 4 g Ca/kg dry matter (DM) in grass hay. Hay with more than 10% of herbs and legumes found only in Switzerland showed higher Ca contents of >7 g Ca/kg DM in hay. The mineral contents of phosphorus and potassium were lower in hay from Switzerland (P: 1.8 ± 0.7 g/kg DM, K: 15.4 ± 5.1 g/kg DM) than from Bavaria (P: 3.8 ± 0.6 g/kg DM, K: 20.0 ± 6.0 DM), whereas the magnesium content of the hay showed no difference between the regions (∼1.5 g Mg/kg DM). Very late first grass hay cuts showed low magnesium and calcium (<4 g/kg DM) contents. Further minerals in the hay for horses differed from those in dairy cattle in the same region. Fertilization showed only small effects on the mineral contents of the hay produced for horses. Therefore, in calculation of ration and production of supplements for horses, these differences should be taken into account.  相似文献   
123.
The influence of forage conservation method on microbial and chemical composition in forage and on colon content and faeces in horses fed with the forages was investigated. Hay (815 g DM/kg), haylage (548 g DM/kg) and silage (343 g DM/kg) was produced from the same grass crop and fed to four fistulated horses in a crossover study. Horses were sampled in right ventral colon and of faeces after a feeding period of 21 days (for each forage). Fermentation kinetics of right ventral colon was also studied on two subsequent days in each period, with sampling times immediately before and 2, 4, 8 and 12 h after the morning meal. Forage conservation method influenced microbial and chemical composition of the forages. Silage differed from haylage and hay in more variables than haylage differed from hay. However, the different forage types had similar influence on microbial and chemical composition of right ventral colon content and faeces in horses at Day 21, with the exception of counts of Streptococci which were highest when horses were fed with hay. However, interaction among forage types and sampling locations (right ventral colon and faeces) was also present for Streptococci as well as for pH. In general, pH was lower and counts of lactate utilizing and lactate producing bacteria were higher in faeces compared to right ventral colon. Fermentation kinetics in colon varied little among forage types and sampling times, and no interaction between forage types and sampling times were found, indicating that silage, haylage and hay had very similar fermentation kinetics in right ventral colon of horses. In conclusion, silage, haylage and hay produced from the same grass crop tended to produce similar responses in microbial and chemical composition in right ventral colon and faeces in horses fed with the forages.  相似文献   
124.
14份燕麦种质在肃南皇城镇的生产性能比较   总被引:1,自引:0,他引:1  
对14份燕麦(Avena sativa)种质株高、产草量、营养、种子产量、千粒重、发芽率等方面进行评比研究,以期筛选出适宜在甘肃省肃南县皇城地区种植的燕麦种质。结果表明,青永久479号植株高度最高,达到151.3 cm;青永久474号最矮,为128.4 cm。青永久12号分蘖最多,为2.0;其余燕麦种质的分蘖都低于2.0。叶茎比变化在1.79~2.46,青永久195号叶茎比最高(2.46),陇燕2号最低(1.79)。陇燕2号干草产量最高,为11.11 t·hm~(-2);巴燕3号最少,为7.71t·hm~(-2)。青永久416号干草粗蛋白含量最高,为8.2%;青永久195号的最低,为6.3%。青永久97号干草酸性洗涤纤维含量最高,为47.4%;加燕2号的最低,为37.4%。中性洗涤纤维含量最低的是青永久233号,为59.5%;陇燕2号最高,为66.7%。巴燕3号、青海444、青永久93、青永久474和甘南燕麦种质能够成熟,适宜籽实农业生产,其中种质甘南的千粒重、发芽率以及种子产量表现最好。综合结果表明,青永久479、青永久167和青永久233适宜在肃南皇城进行营养体农业生产。  相似文献   
125.
获得了草鱼脂蛋白脂酶(lipoprotein lipase, LPL)部分cDNA序列(GenBank注册号为FJ612596),并进行了序列同源性分析;采用半定量反转录聚合酶链式反应(SQ-RT-PCR)方法,检测了LPL基因在草鱼不同组织和不同发育阶段脂肪细胞中的表达状况;研究了饥饿和再投喂对草鱼肝胰脏LPL基因表达的影响。结果显示,所获得的草鱼LPL部分cDNA序列长度为360 bp,与其它物种的同源性为70%~89%; LPL基因在肝胰脏、肌肉、心脏、鳃、腹腔脂肪组织中均表达,其中在腹腔脂肪组织中表达丰度最高,在鳃中表达丰度最低;在成熟脂肪细胞中的表达丰度显著高于基质脉管组分(stromal vascular fraction,SVF)细胞;草鱼LPL基因表达水平在饥饿48 h后显著升高,再次投喂后12 h,回复到0 h的表达水平。研究表明,草鱼LPL在不同组织及脂肪细胞分化的起始和终末阶段均有表达,显示其在草鱼不同组织和脂肪细胞分化中具有重要作用,同时,其表达水平受营养状况的调控。论文首次克隆得到草鱼LPL基因部分cDNA序列,并对其进行了表达分析,研究结果可为LPL在鱼类脂质代谢中的作用研究提供参考和依据。  相似文献   
126.
120只SPF级昆明种雌性小鼠平均分成3组,菌草灵芝孢子粉分三个剂量组给小鼠灌胃,共30d。测定小鼠的体重、免疫器官脏器/体重比值、迟发型变态反应(DTH)、ConA诱导的小鼠淋巴细胞转化能力、抗体生成细胞数、半数溶血值(HC50)、单核一巨噬细胞碳廓清、巨噬细胞吞噬鸡红细胞吞噬率指标。结果:0.150g/kg.bw剂量能提高小鼠的半数溶血值(P〈0.05);0.450g/kg.bw剂量能提高小鼠迟发型变态反应(DTH)能力、ConA诱导的淋巴细胞转化能力、增加抗体生成细胞数(P〈0.05);菌草灵芝孢子粉对小鼠体重增长、胸噱体重比值、脾脏体重比值、单核-巨噬细胞碳廓清能力、小鼠巨噬细胞吞噬鸡红细胞的能力均无明显影响(P〉0.05)。  相似文献   
127.
为明确不同分级指数(Grading index,GI)下牦牛日粮粗饲料营养情况,本试验选取了5种不同GI(7.20,6.43,5.66,4.89,4.12)的玉米青贮—苜蓿干草组合,其质量比分别为70:30,60:40,50:50,40:60,30:70,进行牦牛瘤胃体外发酵试验,旨在探究不同组合下牦牛瘤胃体外发酵效果。试验结果表明:发酵48 h时,GI=7.20组合的累积产气量(Gas production,GP)显著高于或极显著高于其他组合(P<0.05或P<0.01);各GI组合的干物质降解率(Dry matter degradation in vitro,IVDMD)差异不显著(P>0.05);发酵3 h和12 h时,GI=7.20组合的中性洗涤纤维降解率(Neutral detergent fiber in vitro,IVNDFD)与GI=6.43组合差异不显著但极显著高于其他GI组合(P<0.01);3 h,6 h,12 h,24 h时的氨态氮(NH3-N)浓度随着GI降低呈现出减小趋势,48 h时的NH3-N浓度随着GI降低呈现出先减小后增加趋势,GI=7.20时的NH3-N浓度最大;发酵48 h时,各GI组合的微生物蛋白(Microbial protein,MCP)浓度差异不显著(P>0.05),但GI=7.20时的MCP浓度最大;发酵48 h时,乙酸、丙酸、总挥发性脂肪酸(Total volatile fatty acid,TVFA)浓度随着GI降低呈现出减小趋势,GI=7.20时的乙酸、丙酸、TVFA浓度最大;各GI组合发酵6 h~48 h均呈现了正组合效应,综合组合效应值(Multiply factors associative effects index,MFAEI)随着GI减小呈现先减小后增大的趋势,且各时间段GI=7.20组合的MFAEI高于其他GI组合。综上所述,GI值为7.20玉米青贮—苜蓿干草组合的牦牛瘤胃体外发酵效果最优。  相似文献   
128.
The objective of this study was to investigate the effect of daily herbage allowance and concentrate supplementation level offered at approximately 40 and 80 days in milk (DIM) and the carryover effects at 120 DIM on the production performance of spring calving dairy cows. Sixty-six (30 primiparous and 36 multiparous) Holstein–Friesian dairy cows (mean calving date — 7 Feb ± 9.9 days) were randomly assigned to a 6 treatment (n = 11) grazing study. The experiment was a randomised block design with a 3 × 2 factorial arrangement of treatments (3 daily herbage allowances (DHA's; approximately 13, 16 and 19 kg DM/cow/day; > 4 cm) and 2 concentrate allowances (0 and 4 kg DM/day). Treatments were imposed from 21 February to 8 May. Following this period (subsequent 4-weeks) animals were offered a daily herbage allowance of 20 kg DM/cow/day and no concentrate. Milk production, total dry matter intake (TDMI), energy balance (EB) and blood metabolites were measured on three occasions — at approximately 40, 80 and 120 days in milk, R1, R2 and the carryover period, respectively. Cows offered a low DHA had a lower post-grazing sward height but increased sward utilisation (> 4 cm) during R1 and R2, there was no difference during the carryover period. Concentrate supplementation increased post-grazing sward height by 11% during R2 but had no effect during R1 and the carryover period. Daily herbage allowance had no effect on milk yield or composition during R1 however a low DHA tended to reduce milk yield in R2. Concentrate supplementation increased milk and solids corrected milk (SCM) yield by 4.1 and 2.8 kg/cow/day, respectively during R1 and also increased R2 milk production performance, this effect extended into the carryover period. Offering a low DHA restricted grass dry matter intake (DMI) during R1 and R2 yet concentrate supplementation significantly increased total DMI (2.3 (R1) and 3.0 (R2) kg DM/cow). Animals offered a low DHA had a significantly lower bodyweight (BW) than those offered a medium or high DHA during P1 and P2. Concentrate supplementation increased BW during P1 and P2 (+ 9 and + 14 kg/cow, respectively). There was no effect of treatment on BW during P3. There was no effect of DHA on EB in R1; during R2 animals offered a low DHA had the lowest EB. Concentrate significantly increased EB in R1 and R2 and increased plasma glucose concentration while it decreased plasma NEFA and BHB concentrations. The results of this study indicate that animals should be offered a low DHA up to 80 DIM after which DHA should be increased however animals should also be supplemented with concentrate during the early post-partum period.  相似文献   
129.
A study was undertaken to evaluate the effects of incorporating high (HMS) and low (LMS) maturity maize silages into diets based on low (LGS) and high (HGS) feed value grass silages offered to beef cattle. Seventy-two continental cross-bred steers were used in a 14-week continuous design, randomised block experiment. The six treatments were arranged as a 2 × 3 factorial design incorporating the LGS and HGS offered as the sole forage, along with each of the two grass silages offered in a 60:40 ratio (DM basis) with the HMS and LMS. All diets were supplemented with 3 kg/head/day concentrates. Total daily DM and metabolisable energy intakes were higher (P < 0.001) for diets based on HGS compared to those based on LGS. Intakes were similar (P > 0.05) between diets containing LMS and HMS, both of which were higher (P < 0.001) than diets containing grass silage as the sole forage. Highest DM intakes were recorded with a mixture of HGS and HMS (P < 0.05 or greater). Cattle offered diets containing HGS had higher live-weight gain (P < 0.05), final live weight, carcass gain and carcass weight (P < 0.001) than those offered diets containing LGS. Feed conversion efficiency, assessed on a carcass gain basis, was poorer (P < 0.05) with diets containing LGS compared with those containing HGS, though differences between diets containing either LMS or HMS and GS as the sole forage were not significant (P > 0.05).  相似文献   
130.
海南坡鹿饲草粗蛋白质和微量元素含量与喜食性的关系   总被引:2,自引:0,他引:2  
在海南大田国家级自然保护区围栏内,测定海南坡鹿饲草的喜食性;采集坡鹿经常采食的草本植物和灌木各18种,测定其粗蛋白质、铁、锰、锌和铜含量,并分析其与饲草喜食性的相关关系.结果显示,随着粗蛋白质和微量元素含量增加,饲草的喜食性显著提高,海南坡鹿优先摄取粗蛋白质和微量元素含量丰富的饲草.灌木类饲草的粗蛋白质、铁、锰、锌和铜含量分别为12.24%、265.44、61.43、26.72和17.82mg/kg,均显著高于草本类饲草含量(依次为9.39%、142.67、34.05、13.67和9.44mg/kg).灌木是海南坡鹿旱季长达半年多时间里在大田保护区围栏内得以维持平衡的生态营养需要的重要营养源.对海南坡鹿饲草资源量的研究表明,大田保护区围栏内坡鹿喜食的灌木类饲草的可采食资源量在逐步减少,这是由于它们被坡鹿长期选择性采食所导致的.  相似文献   
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