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31.
A topical subject in human nutrition is the steadily growing number of people choosing to limit or completely avoid all animal-derived food products either for moral dilemma, health concerns or both. To meet people's will of applying their dietary choices to their domestic animals, the pet food industry answered by launching on the market some plant-based diets. This leads to concerns about whether these diets are adequately formulated to satisfy the target species nutritional requirements, especially for cats which are still considered strict carnivores. This case report follows a 2-year-old male neutered Main Coon and a 1-year-old female spayed Domestic Shorthair cat, presented to the nutrition service of the University of Toulouse, France. Reason for consultation was lethargy with in anamnesis a recent dietary transition to a plant-based pet food. Dysorexia, lethargy and muscle waste were present at first consultation. Progressive weight loss developed during follow-ups. A macrocytic, non-regenerative anaemia with serum folates below reference were the main clinical features. Analysis of pet food showed multiple nutrients below minimum recommendation at the average daily intake of both cats. Folic acid supplementation improved dysorexia, and subsequent reintroduction of animal-derived ingredients in the diet restored appetite, weight and a normal mentation in both cases.  相似文献   
32.
为研究不同利用方式对藏北高寒草甸建植一年生燕麦(Avena sativa Linn.)人工草地的土壤理化性质及土壤细菌群落的影响,本试验于8月份植物生长旺季,在持续利用人工草地(AG)、撂荒人工草地(AC)和对照天然草地(NG)采集土壤样品,分析了土壤理化性质、土壤细菌群落组成和结构特征变化。结果表明,AG样地土壤有机质、全钾含量和pH与NG样地相比无显著性变化,土壤全氮、速效氮和速效钾含量显著降低;AC样地与NG样地相比土壤pH显著升高,土壤有机质、全氮、速效氮和速效钾含量显著降低。AG样地土壤细菌群落Chao1,Shannon和Pielou均匀度指数显著高于NG样地,AC样地酸杆菌门和变形菌门丰度显著升高。土壤理化性质是土壤细菌群落结构组成门、属相对丰度变化主要影响因子。综上所述,高寒草甸一年生燕麦人工草地长期利用应科学补充肥料,保持土壤肥力;草地撂荒需谨慎,应及时采取恢复措施避免草地发生退化。  相似文献   
33.
Gastrointestinal microbiota play a key role in the nutrients digestion and hence maintaining animal health and welfare. The diet offered to the animals in captivity may differ considerably from that on natural pastures. In a stabled maintenance system, horses have a limited choice of habitat and feed. Time spend for feeding is relevant for equine welfare because the reduction of the time devoted for foraging may be responsible for inducing gastric inflammation and ulceration. Therefore, in the present study, it was hypothesized that fecal bacterial fermentative processes differ between free-roaming and stabled Konik Polski Horses (KPHs) with respect to microbial enzymatic activity, and thus the fecal concentration of short-chain fatty acids (SCFA), which can be further utilized for assessing the feeding behavior and welfare in free-roaming versus stabled horses. The SCFA concentration and profile, as well as the extracellular and intracellular activities of selected bacterial enzymes, were characterized in horse feces collected during the winter and summer feeding seasons. The results showed higher enzymatic activity and SCFA production in the feces excreted by free-roaming versus stabled horses, especially during summer. An increase in pasture plant diversity may be beneficial for the gastrointestinal microbiota and hence for maintaining health and welfare.  相似文献   
34.
塔克拉玛干沙漠腹地人工绿地土壤及其影响因子分析研究   总被引:1,自引:0,他引:1  
周智彬  徐新文 《土壤通报》2001,32(Z1):37-40
塔克拉玛干沙漠腹地绿地建设长期使用4.0g/L以上的高矿 化度地下水及生活污水灌溉,对土壤的理化、生化性质产生了重大影响.通过6年的定位试验 观测,数据表明原沙漠腹地风沙土0~2m内可溶性离子总量下降,2m以下增加;土壤粘粒、 有机质含量增加;土壤容重降低;土壤紧实度除表层以外,各层土壤由紧变松;土壤肥力显 著增强;土壤微生物的数量大幅增加,生物活性趋强.  相似文献   
35.
This study assessed the effect of oral supplementation with the primary antioxidants and fatty acids involved in spermatogenesis (L-carnitine, selenium, vitamin E, omega-3, and omega-6) on the seminal quality in fresh, cooled, and frozen semen of stallions (n = 8), using a randomized design. The animals were divided into Group I (n = 4) and Group II (n = 4) for a 30-week experiment. The two groups alternated between nutraceutical supplementation and a placebo over the course of the experiment. Semen collections were performed in two sets: once in the middle of the experiment, before the two groups switched treatments, and once at the end. The volume, appearance, sperm concentration, spermatozoa kinetics, and membrane integrity of fresh semen were evaluated. The spermatozoa kinetics and membrane integrity of cooled (for 24, 36, and 48 hours) and frozen semen were also evaluated. No differences were observed in volume, appearance, and sperm concentration between treatment and control. However, compared with placebo, nutraceutical supplementation increased (P < .05) total motility, trajectory speed, as well as plasma and acrosomal membrane integrity in spermatozoa from fresh semen. In cooled semen, nutraceutical treatment also increased (P < .05) total motility, speed, and membrane integrity of spermatozoa compared with the control. In frozen semen, supplementation increased (P < .05) spermatozoa progressive motility and plasma membrane integrity. Our results suggest a positive, synergistic effect of the antioxidant L-carnitine and selenium on spermatozoa kinetics. Similarly, the increase in plasma and acrosomal membrane integrity could be attributed to higher concentrations of polyunsaturated fatty acids (a key cell-membrane component), combined with the prevention of excess lipid peroxidation by antioxidants. In conclusion, supplementation with nutraceuticals containing fatty acids and antioxidants improved the quality of fresh, cooled, and frozen stallion semen. Therefore, nutraceutical use should increase the success of artificial insemination with cooled and cryopreserved semen.  相似文献   
36.
Harvesting, handling and transporting quails to the slaughterhouses, other farms and laboratories might covertly reduce their welfare. The aim of this study was to evaluate the effects of two major sources of energy in poultry nutrition on reducing transportation stress in Japanese quail (Coturnix Coturnix japonica). Male quails (n = 60) were divided into two groups. The first group was fed corn‐based diet, and the second was fed wheat‐based diet supplemented with xylanase and phytase. At the end of the experiment (day 35), quails were subjected to 80 km of transportation. Immediately on arrival and after 24 h, heterophil counts, lymphocyte counts and H:L ratios were measured. On arrival, H counts were lower, L counts were higher, and H:L ratios were lower for corn‐fed group. After 24 h, wheat‐fed group showed lower increment of H counts, greater increment of L counts and also decrement of H:L ratios rather than corn‐fed group which showed increment of H:L ratios. However, these ratios were still lower in corn‐fed group. Results indicate that corn‐based diets can help Japanese quail to better resist transportation stress, although it seems that feeding wheat‐based diets supplemented with xylanase and phytase could have positive effects for coping better with stress after journeys.  相似文献   
37.
为探究多年生人工草地在青海湖流域的适应性和稳定性,本研究以青海草地早熟禾(Poa pratensis. Qinghai)和青海中华羊茅(Festuca sinensis. Qinghai)单播及混播人工草地为研究对象,分析不同种植方式下人工草地植被和土壤养分特征的变化。结果表明:青海草地早熟禾+青海中华羊茅混播草地和青海草地早熟禾单播草地的生物量和盖度高于青海中华羊茅单播草地,且在生长旺期(8月),青海草地早熟禾+青海中华羊茅混播草地生物量最高,为586.2 g·m-2;青海草地早熟禾单播、青海中华羊茅单播和青海草地早熟禾+青海中华羊茅混播草地间土壤有机质、全氮、全磷、硝态氮、铵态氮和土壤含水量在相同土壤深度下差异不显著,但土壤氮、磷及有机质间存在显著的相关性。综上所述,在青海湖流域建植青海草地早熟禾+青海中华羊茅混播型人工草地可以获得较高的产量,但需在种植和管理过程中协调好土壤氮、磷间的关系。  相似文献   
38.
半夏小块茎的形态发生及人工种子制作   总被引:25,自引:1,他引:25  
何奕昆  朱长甫 《作物学报》1997,23(4):482-486
离体培养中,经过小块茎发生途径从半夏叶柄诱导了完整植株。用实体解剖、连续切片和三维结构重组等方法观察分析得出:小块茎顶端的叶原基由于不对称生长逐渐将顶端分生组织复盖,随后叶原基的尖端和两侧生长延缓,生长中心转移到背轴面中央,结果导致叶原基长帽状结构。不同发育程度的雏叶和叶原基总是相互叠在一起顶端分生组织复盖于下面。小块茎枯端形成芽的同时,在顶芽附近分化根。  相似文献   
39.
基于气温预报和神经网络的参考作物腾发量预报   总被引:2,自引:0,他引:2  
采用反向传播人工神经网络(BP-ANN)逼近气象因子-参考作物腾发量ET0函数关系,以天气预报中的最高和最低气温为输入进行短期ET0预报。收集了南京站实测的2010年7月1日至2013年7月7日逐日气象数据和2012年7月1日至2013年6月30日逐日对未来7d的气象预报数据,以最高、最低气温及相应的日序数为3个输入因子,ET0为输出建立一个包含一个隐含层的3层BP网络,以2010年7月1日至2012年6月30日实测气象数据及通过FAO-56PM公式计算的ET0进行网络,以2012年7月1日至2013年6月30日实测气象数据及通过FAO-56PM公式计算的ET0进行网络验证。将2012年7月1日至2013年6月30日逐日对未来7d的气象预报中的最高、最低气温输入训练及验证后的网络,得到2012年7月1日至2013年6月30日逐日对未来7d的ET0预报值,并与FAO-56PM公式计算的ET0值进行比较以验证预报精度。结果表明,预见期1~7d内,预报的ET0和计算的ET0变化趋势基本一致,预报精度随着预见期的增加而降低;平均准确率(±1.5mm/d以内)达88.08%,相关系数为0.77,均方根误差为1.28mm/d,显示出了较高的预报精度。在局部时间段内出现的ET0,PM和预报ET0的较大差别的原因是该时段内的ET0更多地受到除了日最高和最低气温之外的其他因素的影响。提出的方法 ET0预报,随着气象预报准确度的提高,可实现较为精确的ET0预报。  相似文献   
40.
在人类历史的发展中,世界各文化圈都创造了自己独特的民俗,有着对自己民俗文化的独特理解。本文拟以中国民俗文化为参照,以民俗活动的时间性为切入点,从四个方面比较中西方民俗文化之异同,即饮食文化、节日文化、民族风情、禁忌。这给予我们一个简明的中西方比较,对英语学习者了解他们之间的异同很有帮助,以此观照汉文化圈中民俗审美的特性,不同的语言产生于特定的文化背景、社会生活、民俗风情。  相似文献   
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