贺兰山特有植物花粉形态特征研究

采用扫描电子显微镜并辅以光学显微镜，分别对11种贺兰山特有植物的花粉形态进行了观察，描述了其大小、形态、表面纹饰、萌发器官类型等特征。根据相关方面资料和野外原始记录，记载了这些植物的花期、生境、分布和产地等，为研究贺兰山植被及与阿拉善荒漠植被 间的关系提供了孢粉学依据。     

贺兰山荒漠草原几种主要植物花粉形态观察

通过扫描电镜观察结果,描述了贺兰山荒漠草原植被6科、8属、10种主要植物的花粉形态特征。结果表明,在扫描电镜观察下,每种植物花粉的轮廓、形状、大小、表面纹饰、萌发器官类型及数量各不相同;同科或同属内种间总体形态特征相似,而细微特征存在明显差异。     

海拔梯度对贺兰山岩羊主要活动区植物群落特征的影响

研究贺兰山岩羊主要活动区植物群落组成和物种多样性在不同海拔梯度的变化规律对贺兰山岩羊的合理管护具有重要意义。本研究通过贺兰山岩羊主要活动区植被调查,对不同海拔的数据进行单因素方差分析和回归分析,阐明1100~1500 m、1500~2000 m、2000~2500 m和大于2500 m的4个海拔段岩羊主要活动区植物物种组成和物种多样性的变化,探讨植被与岩羊等草食动物的关系及海拔对植物物种多样性的影响。结果表明：贺兰山岩羊主要活动区植被共记录到30科62属87种,主要为禾本科、蔷薇科和菊科等植物;同时,不同海拔梯度上的科、属、种的数量和组成存在差异。随着海拔上升,岩羊主要活动区的草本植物的物种丰富度升高,Pielou均匀度指数、Shannon-Wiener多样性指数和Simpson优势度指数表现为先降低后升高的特征;灌木植物物种丰富度、Pielou均匀度指数呈现出沿海拔上升而降低的特征,Shannon-Wiener多样性指数和Simpson优势度指数呈现出先增加后降低的特征。因此,针对不同海拔植物物种多样性的不同,建议对岩羊的合理管护在不同海拔地区采取不同措施,以达到防止植被退化和促进岩羊种群健康发展的目的。     

贺兰山不同海拔植被生物量与土壤分形特征和土壤水分的相关关系

为了解干旱与半干旱区域山地生态系统植被生物量与土壤分形特征和土壤水分含量的垂直分异规律，探究植被生物量与分形特征和土壤水分的相关关系，选取贺兰山不同海拔典型植被带作为研究区，采用单因素方差分析、Pearson相关分析等方法分析植被生物量、土壤分形特征和土壤水分含量的垂直分异特征及三者间相互关系。结果表明：1）草本植被生物量与灌木植被生物量沿海拔未呈明显的线性变化趋势，灌木植被生物量在浅山灌丛（QSGC）样地具有最大值，草本植被生物量在亚高山灌丛（YGSGC）样地具有最大值，植被条件较好，植被生产力较高。2）贺兰山土壤颗粒以粉粒和极细砂粒为主，随着海拔的升高，土壤质地变细。3）土壤水分含量随海拔增高显著增加，但在青海云杉（QHYS）样地土壤水分含量略低。4）相关分析表明，年降水量以及土壤黏粒含量是影响植被生物量的主要因子。总体上，贺兰山植被生物量、土壤分形特征以及土壤水分含量受多个环境因子共同作用和影响，呈明显的空间异质性。本研究对于揭示贺兰山植被生物量空间变化机制及促进贺兰山退化植被恢复具有重要的意义，可为促进贺兰山山地生态系统植被与土壤资源合理利用提供参考。     

贺兰山山地疏林草原主要植物花粉形态观察

采用扫描电子显微镜,对贺兰山山地疏林草原建群种、优势种、伴生种等10种主要植物的花粉形态进行了细致的观察,并进行了详细的描述.掌握了它们在扫描电子显微镜下的形态特征.结果表明,在扫描电子显微镜下,花粉的外壁纹饰非常清晰,萌发器官类型鉴定准确.同时表明这10种归属于不同科、属的植物,其花粉形态均存在明显差异.     

贺兰山山地疏林草原主要植物花粉形态观察

采用扫描电子显微镜,对贺兰山山地疏林草原建群种,优势种、伴生种等10种主要植物的花粉形态进行了 细致的观察,并进行了详细的描述。掌握了它们在扫描电子显微镜下的形态特征。结果表明,在扫描电子显微镜下,花 粉的外壁纹饰非常清晰,萌发器官类型鉴定准确。同时表明这10种归属于不同科、属的植物,其花粉形态均存在明显差异。     

干扰与植被的关系

干扰与植被的关系主要表现在干扰对物种的进化意义和干扰对植被过程的调整作用，在研究干扰和植被的关系时，生态学家将干扰进行了抽象和分解，植物种对干扰的适应表现在繁殖，物候，形态、生理等方面，植物特性间的均衡，植物的形态可塑性，植物多样性是植被适应干扰的机制，在分析植被对干扰的适应时，生态学家引入了功能类型，对策等概念框架，干扰对植被的作用有正反两个方面，不同的干扰类型，强度，频度，历史具有不同的作用，放牧，火烧，洪水，风沙，刈割和砍伐等干扰方式对植被的正负作用得到了生态学界的广泛重视,针对全球尺度的扰动与植被关系研究是目前扰动生态学研究的核心问题，但是，由于生态研究的特殊性，很多相关的问题还未被解决。     

贺兰山低山区土壤种子库与地上植被关系分析

土壤种子库是地上植被更新的潜在种源,它影响地上植被的自然恢复、植被群落的演替进程和区域生物多样性维持。通过对贺兰山低山区不同海拔高度植物群落进行室内种子萌发试验和野外植被调查,发现5个海拔高度的土壤种子库植物种均以一年生草本居多,而相对应的地上植被群落在5个海拔高度的物种重要值均呈现为一年生草本<灌木或半灌木<多年生草本;土壤种子库和相对应的地上植被的物种多样性指数均在海拔1 200 m处最高;土壤种子库种子密度与相对应的地上植被密度的关系可用对数曲线表示,随着地上植被密度的增加土壤种子库种子密度呈减少趋势。贺兰山低山区5个海拔高度土壤种子库种子密度和物种多样性均较低,无法满足植被自然恢复需求,可通过采取飞播等生态恢复措施来弥补表层土壤种子的不足,从而满足地上植被恢复所需种子数量。     

贺兰山野化牦牛夏季食性分析

2010年6⁸月,在贺兰山的哈拉乌沟、甘沟、樊家营子等沟段收集了野化牦牛夏季的新鲜粪便,采用粪便显微分析法研究了野化牦牛的夏季食性。结果表明:夏季野化牦牛共取食13科21种(属)植物,珠芽蓼、内蒙葶苈、高山柳、针茅、梭草、禾叶凤毛菊为野化牦牛夏季取食主要食物,其中猪芽蓼(14.69%)是牦牛最喜食植物。在贺兰山野化牦牛夏季取食的各科植物中,禾本科(22.48%)、廖科(14.69%)、莎草科(13.14%)为主要取食植物。贺兰山野化牦牛夏季取食非禾本科草本植物最高,比例达到59.20%;其次为禾本科草本,比例为22.74;灌木排名第3,比例为16.77%。夏季牦牛Shannon-Wiener指数为-3.794,Pielou均匀度指数为-1.246,食物生态位宽度为13.581。同时将贺兰山野化牦牛夏季食性与冬春季节食性进行了比较。     

改造鼠荒地,改善草原生态环境

鼠荒地是害鼠破坏草原植被以后形成的次生裸地。在鼠荒地上 ,原生植被破坏率达80 %～ 90 % ,并滋生一、二年生杂草 ,植被稀疏 ,群落结构简化 ,植被盖度不及 10 % ,地上植物量为37.5～ 152 .5kg/hm2 。土壤侵蚀严重 ,地表形态支离破碎 ,并出现沙化特证 ,对周边草场构成沙尘暴和扬沙威胁。进一步对鼠荒地的发生与发展、鼠荒地的生态环境特征等问题作了深入论述 ,并针对鼠荒地提出了几项有效的改造措施。     

荷斯坦牛初乳白利糖度值和初乳产量特征及影响因素分析

为探究荷斯坦牛初乳白利糖度值和初乳产量特征及其影响因素,本研究收集了北京地区某牛场2016年6月—2018年6月共1 257头荷斯坦牛初乳白利糖度值和初乳产量数据及对应的奶牛生产性能测定数据,利用SAS 9.2软件的GLM过程分析胎次、产犊季节和产犊年份对初乳白利糖度值和初乳产量的影响。结果表明:北京地区荷斯坦牛初乳白利糖度值为24.25%,初乳产量为6.52 kg,该试验场初乳品质较好;不同胎次、产犊季节和产犊年份对初乳白利糖度值和初乳产量均有显著影响;初乳白利糖度值随胎次增加总体呈逐渐增加的趋势,5胎及以上的初乳白利糖度值最高;初乳产量随胎次增加呈先增加后减少的趋势,4胎时初乳产量最高。综上,荷斯坦牛初乳白利糖度值对分娩母牛的胎次和产犊年份、季节等生理和环境因素的变化较为敏感。     

Seasonal Effect on Zebu Embryo Quality as Determined by Their Degree of Apoptosis and Resistance to Cryopreservation

In order to optimize the production of embryos under tropical conditions and to test a possible seasonal effect on embryo quality, 40 Zebu cows were superovulated during the dry season (April to May) and during the rainy season (July to August). A total of 116 (average 2.7/cow) and 83 embryos (3.5 average/cow) were obtained during the respective seasons. After classification as good, fair or poor quality, embryos were tested based on their ultrastructural differences (n = 53 dry season 16 good, 20 fair and 17 poor and n = 61 rainy season 21 good, 20 fair and 20 poor) and their degree of apoptosis using the TUNEL technique (n = 30 during the dry season and n = 55 in the rainy season). Structural characteristics determining embryo quality varied between good and fair quality embryos. No difference, however, was observed between good, fair and poor quality embryos from the two seasons. The number of TUNEL-positive cells was different among embryos (p < 0.001), being lower in labelled cells of good quality embryos regardless of the season. Fewer apoptotic cells were observed in embryos assigned in all three quality levels during the rainy season (p < 0.001). Ultrastructural evaluations confirmed the results obtained by TUNEL. Cryopreserved embryos of good (n = 25 in each season) and fair quality (n = 11 dry season; n = 17 rainy season) showed a significant decrease of TUNEL-positive cells during the rainy season (p < 0.05). Results suggest that embryos collected in the dry season have more cellular damage in contrast; embryos cryopreserved in the rainy season appeared morphologically better equipped to result in a pregnancy following transfer.     

泌乳阶段与产奶季节对初产奶牛牛乳体细胞数的影响

为探究初产奶牛牛乳体细胞数在不同泌乳阶段和产奶季节的变化规律,旨在为采取合理措施降低牛乳体细胞数和改善乳品质提供理论依据,研究以2012年5月至2013年4月期间选择2126头初产奶牛13168条DHI测定记录,以泌乳阶段和产奶季节及其两者的互作作为研究因子,分析泌乳阶段和产奶季节及其互作对初产奶牛牛乳体细胞数（SCC）变化规律的影响。结果表明,泌乳阶段和产奶季节及其互作对体细胞数评分（SCS）具有极显著的影响（P〈0．0001）。初产奶牛于泌乳早期牛乳SCC较高（294．16×10^3个／mL）,随着泌乳月龄的增加,SCC逐渐降低,泌乳中期（192．71×10^3个／mL）和泌乳晚期（185．51×10^3个／mL）牛乳SCC基本保持稳定;初产奶牛泌乳早期牛乳SCS比泌乳中期和泌乳晚期极显著升高（P〈0．01）;初产奶牛牛乳SCC冬季最高（312．72×10^3个／mL）,春季次之（236．48×10^3个／mL）,秋季最低（168．59×10^3个／mL）;初产奶牛冬春季牛乳SCS比夏秋季极显著升高（P〈0．01）。奶牛乳中体细胞数受胎次、泌乳月龄、产奶季节等因素的影响。产奶季节对SCC的影响主要反映了温度和湿度因素对奶牛的影响。     

The effect of first season chemoprophylaxis in calves on second season pasture contamination and acquired resistance and resilience to gastrointestinal nematodes

Two groups of second grazing season cattle, which had been treated with an ivermectin-sustained-release bolus (ISRB) in their first grazing season, were monitored during consecutive years (1995 and 1996) on the same second grazing season pasture. In the preceding year (1994), this pasture had been grazed by yearlings that had not received chemoprophylaxis in their first grazing season. The objectives of the study were, firstly, to investigate whether the chemoprophylactic-treated yearlings were less resistant to gastrointestinal nematodes upon subsequent exposure, and hence excreted more strongyle eggs compared to the control yearlings; secondly, whether an increased susceptibility of the previously treated animals resulted in a yearly increase of the pasture infestation on the second grazing season pasture; and finally, whether this affected the second year weight gain of the animals. In 1996, the yearlings that had been chemoprophylactic-treated in 1995 excreted higher numbers of nematode eggs, compared to the previously ‘untreated' yearlings. In addition, the proportion of Cooperia larvae was markedly higher in the faecal cultures from the chemoprophylactic treated-animals, suggesting a negative effect of preventive treatment with an ISRB on the acquired resistance of the animals. However, there was no evidence that the slightly higher egg output in the previously treated yearlings had an effect on the larval contamination of the second grazing season pasture. A significant yearly decrease in the second season average daily weight gains was observed, but it could not be inferred from the results of the parasitological parameters that the differences in second year growth were caused by different levels of resilience between chemoprophylactic-treated and -untreated animals. As the study covered three consecutive second grazing seasons, an effect of differences between years (e.g. in weather conditions or grass growth) on the results cannot be excluded.     

Ostertagiasis in calves. I. The effect of control measures on infection levels and body weight gains during the grazing season in Denmark

The investigation was designed to study the gastro-intestinal helminth infection established in yearling calves with reference to fluctuations in the larval contamination of the herbage during the grazing season. In a 2 × 3 factor experiment, comprising six groups, each of six calves, a comparison was made between infection levels, growth rates etc. in calves grazing the same paddock over an entire season and calves moved before the July rise in herbage contamination to paddocks not grazed earlier in the same season. A comparison was also made between animals receiving no anthelminthic treatment, animals treated 3 weeks after the start of the grazing season and again when moved, and animals treated every 3 weeks during the season.Before July there were no weight gain differences between the various groups of calves. During the rest of the season, the calves which were moved gained 647–869 g, while those that remained on the same paddock, and were exposed to a high level of larval contamination gained only 81–361 g per day. The effect of anthelmintic treatment was less pronounced, though significant. The weight gains were correlated to a high degree with the larval contamination levels of the respective paddocks (r = ? 0.79) as well as with the serum pepsinogen (r = ? 0.75) and albumin levels (r = 0.75) of the calves and to a minor degree also with faecal egg counts (r = ? 0.45). The observed weight gain differences could not be accounted for by differences in grass quantity or quality.     

Effect of intensity of defoliation by goats at different phenophases on leaf and shoot growth of acacia karroo hayne

Abstract

Defoliation by goats (leaves plus shoots) during the growing phenophases resulted in a considerable stimulation of leaf and shoot growth relative to non‐defoliated plants. The response differed considerably depending on the intensity and phenophase of defoliation. Plants were most susceptible to defoliation and young shoot removal during the spring flush when carbohydrate levels were at their lowest. During the rest of the growing season carbohydrate levels were high. At these times moderate to heavy (50 % to 75 % leaf removal) defoliations resulted in the greatest leaf and shoot growth.

In contrast, the initial and continuing impact of avian and insect consumption of leaves only reduced leaf and shoot production. The stimulatory effect of defoliation in one season carried through the dormant season to the following growing season. Defoliations during the dormant season did not have any positive or negative impact on plants relative to non‐defoliated plants. Leaf and shoot material removed when the plants were growing, was replaced within weeks of defoliation.     

黑麦草高产栽培技术及利用研究进展

从品种选择、合理施肥、耕作方式、播种量、播种季节等环节系统综述了当前国内黑麦草栽培获得高产的技术措施,归纳总结了黑麦草在饲养牛、羊、鹅、兔日粮配制中的最佳添加比例及取得的经济效益,提出了黑麦草在草地生态畜牧业建设中的研究重点。     

Effects of seasonal variation,group size and sex on the activity budget and diet composition of the addax antelope

Behaviour and diet composition are critical elements in conservation biology within the scope of reintroduction programs. Here we focused on addax (Addax nasomaculatus), a Critically Endangered antelope species, in the Jbil National Park, Tunisia. In this study, we advanced the hypothesis that season, day period, sex and social structure have an effect on the activity budgets and diet composition of addax. Three groups were selected (large group, adult pair and solitary male). Resting, moving, grazing, vigilance and other behaviours were recorded during two seasons (dry and wet) and in the morning and the afternoon. In addition, faecal samples were collected. The results indicate that season and day period were the main factors affecting the activity budgets. The resting behaviour increased from the wet to the dry season, and from morning to afternoon. The grazing and moving behaviours increased during the wet season and decreased from morning to afternoon. Addax select a mixed diet composed of perennial and herbaceous plant species notably during the wet season. In addition, we observed that addax modify their behaviour according to the season and forage availability. This represents an adaptive strategy to survive in a desert climate with a stochastic low-resource environment and depending on ambient climatic conditions.     

八种肉用犬的繁殖性能研究

本文通过对狼犬、鞑子犬、青龙犬、大丹犬、英卡犬、沙皮犬、藏鳌、拿波伦犬等8个品种192只犬繁殖性能研究。发现这八种犬的发情季节多集中在3月份和10～11月份，发情持续时间一般为14d，交配最佳时间为11d。配种次数与窝产仔数间不存在相关。     

产犊季节对荷斯坦牛第一胎泌乳性能的影响

[目的]为了研究不同产犊季节对荷斯坦奶牛第一胎泌乳性能的影响,以便为长江中下游地区荷斯坦奶牛合理安排配种时间提供科学依据。[方法]利用海丰奶牛场有限公司2009年引进2480头澳系进口荷斯坦牛产犊季节及其第一胎泌乳性能的数据,分析不同产犊季节对第一胎泌乳天数、全泌乳期实际产奶量、305d校正奶量、305d脂肪产量和305d蛋白产量的影响。[结果]表明:不同产犊季节对第一胎泌乳天数和全泌乳期产奶量影响极显著(P0.01),显著影响305天脂肪产量(0.01P0.05),春季产犊的奶牛泌乳天数最长(358±10d),而冬季产犊的奶牛泌乳天数最短(299±18d),春季与夏季产犊奶牛的全泌乳期产奶量显著高于秋季、冬季产犊奶牛(P0.05),夏季产犊奶牛305d脂肪产量最高。[结论]综合各产犊季节样本量及相应泌乳性能,认为该场澳系进口荷斯坦牛最适宜产犊季节为夏末秋初,此时泌乳性能最好。该结果对同类地区引进澳系进口荷斯坦牛繁殖与生产管理有借鉴作用。