Tracking Collembola feeding strategies by the natural C signal of fatty acids in an arable soil with different fertilizer regimes     

Christopher Ngosong  Joachim Raupp  Liliane Ruess 《Pedobiologia》2011,54(4):225-233

Compound specific stable isotope analysis (¹³C/¹²C ratio of fatty acids) was used to assess the allocation of plant carbon in soil microbiota, and to identify the trophic links to microbial grazers in an arable field with long-term mineral and organic fertilizer amendments. The feeding strategy of two dominant Collembola species, epedaphic Isotoma viridis and euedaphic Willemia anophthalma was determined. The investigation was conducted following a shift to amaranth, a C₄ plant, after 27 years of continuous C₃ crop rotation. The influence of new C₄ plant carbon was observed in microbial phospholipids (PLFAs) with higher δ¹³C recorded in C₄ amaranth than in C₃ clover soils. The strongest enrichment occurred in the fungal PLFA 18:2ω6,9c and bacterial PLFA 18:1ω9t with 11.2‰ and 6.6‰, respectively. However, other bacterial PLFAs showed no isotopic change, suggesting that the microbial community simultaneously utilized “new” and “old” plant carbon. The δ¹³C of Collembola fatty acids displayed species specific lipid pattern, which was affected by crop type, but not fertilizer amendments. Isotopic separation of Collembola lipids from amaranth and clover plots was more distinct in I. viridis than W. anophthalma. With up to 18‰, the enrichment in Collembola lipids was stronger than in microbial PLFAs, pointing to a distinct incorporation of carbon resources originating from the actual plant residues. The δ¹³C pattern in I. viridis indicated trophic links with bacteria, saprotrophic fungi and plant tissues, while saprotrophic fungi and plant tissues were accountable for the patterns observed in W. anophthalma.  相似文献   

Results of a Hypoallergenic Diet Survey of Veterinarians in North America with a Nutritional Evaluation of Homemade Diet Prescriptions     

PHILIP ROUDEBUSH  CHRISTOPHER S. COWELL 《Veterinary dermatology》1992,3(1):23-28

Abstract— One hundred and sixteen veterinarians in North America completed a survey recording the use of specific commercial hypoallergenic diets in dogs and cats, ingredients recommended for homemade diets, and perceptions about problems with, or unacceptable ingredients in, current commercial pet foods. A wide variety of both commercial and homemade rations was recommended by the respondents for dogs and cats suspected of having adverse reactions to food. Homemade diets were recommended most often as the initial test diets for both dogs and cats with suspected food allergy. Ingredients recommended most often for homemade diets were lamb, lamb baby food, rice, potatoes, rabbit, fish, venison and tofu. Unacceptable ingredients in commercial pet foods mentioned multiple times included preservatives and dyes, wheat, beef, fish or fish meal, poultry/chicken, egg, soy and dairy products. Homemade diet recommendations of the respondents were evaluated for their nutritional adequacy. Most (90 per cent) of the homemade elimination diets were not nutritionally adequate for adult maintenance based on currently available recommendations. Résumé— 116 vétérinaires d'Amérique du Nord ont participéà une enquête sur l'utillsation d'aliments hypoallergéniques commerciaux pour chien et chats, les ingrédients recommandés dans les préparations ménagères et les recommandations concernat les problèmes rencontrés avec les aliments courrants industriels ou les ingrédients inacceptables dans leur composition. Un très large éventail de regimes ménagers ou industriels étaient recommandés par les participants pour les chiens et les chats suspects d'intolérance alimentaire. Des préparations ménagères étaient le plus souvant recommandées comme test d'exclusion, pour les chiens et les chats suspects d'allergie alimentaire. Les ingrédients les plus souvents recommandés étaient: viande d'agneau, viande d'agneau en pots pour bébés, riz, pommes de terre, lapin, poisson, gibler et pâte de soja. Les ingrédients mentionnés plusieurs fols comme étant à exclure des preparations industrielles étaient: conservateurs et colorants, bié, viande de boeuf, poisson, volaille, ouef, soja et produits laitiers. L'équilibre des preparations ménagères recommandées par les participantrs a étéétudié. La piupart (90 pour cent) de ces preparations étaient déséquilibrées par rapport aux recommendations courament admises pour l'entretien d'un chien adulte. Zusammenfassung— Einhundertsechzehn Tierärzte in Nordamerika nahmen an einer Umfrage teil, die folgende Punkte untersuchte: Einsatz von bestimmtem kommerziellen hypoallergenen Diätfutter für Hund und Katze, für hausgemachtes Diätfutter empfohlene Zutaten und Probleme mit gängiger kommerzieller Tiernahrung oder mit darin enthaltenen unannehmbare Inhaltsstoffen. Eine große Vielfalt sowohl von kommerziellen als auch hausgemachten Diäten wurde von den Befragten für Hunde und Katzen mit Verdacht auf adverse Reaktionen auf Futter empfohlen. Hausgemachte Diäten wurden am häufigsten als initialer Test für Hunde und Katzen mit Verdacht auf Futtermittelallergie empfohlen. Die am häufigsten empfohlenen Zutaten für hausgemachte Diäten bestanden in Lammfleisch, Lamm-Babynahrung, Reis, Kartoffeln, Kaninchen, Fisch, Wild und Tofu. Die als unannehmbar mehrfach genannten Inhaltsstoffe in kommerzieller Tiernahrung schließben Konservierungs-und Farbstoffe, Weizen, Rindfleisch, Fisch oder Fischmehl, Geflügel/Huhn, Ei, Soja und Milchprodukte mit ein. Die hausgemachten Diätemfehlungen der Befragten wurden auf ernährungsphysiologische Ausgewogenheit überpfrüft. Die meisten der hausgemachten Eliminationsdiäten [90%] waren nach den gängigen Ernährungsempfehlungen für den Erhaltungsbedarf erwachsener Tiere ernährungsphysiologische nicht ausgewogen. Resumen Cientosésis veterinarios en Norteamérica llevaron a cabo una estadística del uso de ciertas dietas comerciales hipoalergénicas en perros y gatos, ingredientes recomendados en dietas caseras e impresiones de los problemas causados por ingredientes inaceptables en la dietas comerciales de uso corriente. Los casos responsivos indicaban una gran variedad de comidas caseras y dietas comerciales para perros y gatos, en los que se sospecharon reacciones adversas a los alimentos. Dietas caseras se recomendaron mas frecuentamente como test inicial para ambos, perros y gatos sospechosos de algeria alimentaria. Los ingredientes más comunmente recomendados fueron cordero, alimento para bebé basado en cordero, arroz, patatas, conejo, pescado, venado y tofu. Ingredientes inaceptables en dietas comerciales mencionados en multiples ocasiones incluyeron preservativos y tintes, trigo, vacuno, pescado o harina de pescado, pollo/aves de corral, soja y productos lácticos. Las dietas caseras recomendadas de los casos responsivos se evaluaron por su eficacia nutricional. La mayoría de las dietas caseras de tests de eliminación, el 90%, no eran adecuadas desde el púnto de vista nutritivo papa la manutención de animales adultos, comparada con las corrientes recommendaciones.  相似文献   

生长肉鸭体蛋白周转的营养生理效应研究   总被引：7，自引：0，他引：7  

周安国  漆良国 《畜牧兽医学报》1995,26(2):97-103

选２７０只１日龄天府肉鸭，采用单因子试验设计，用同位素（Ｌ－〔４，５－＾３Ｈ〕Ｌｙｓｉｎｅ）示踪的大剂量法研究了肉鸭体蛋白周转的营养生理效应和周转代谢规律。试验结果表明：正常营养条件下，肉鸭体重、日增重、饲料利用效率与ＦＳＲ（体蛋白合成率）极显著地呈二次曲线相关（Ｒ＝１，Ｐ＜０．０１）。相对生长率、日粮粗蛋白利用效率随体蛋白周转率降低而下降（Ｐ＜０．０１）。体蛋白周转强度明显比其它禽和哺乳动物大。  相似文献   

家蚕饲料效率的研究——Ⅰ.家蚕叶丝转化率生理因素   总被引：1，自引：0，他引：1  

丁窕  徐卫华 《蚕业科学》1991,17(4):193-199

调查了不同世代五龄逐日食下量、消化量、体重和叶丝转化率,分析了影响家蚕叶丝转化率的有关生理因素,结果,家蚕叶丝转化率为食下鲜叶量的2％-2.4％,不同世代及品种间存在着极显著的差异。叶丝转化率的高低与五龄逐日食下量、消化量、消化率及体重增长有明显的关联。叶丝转化率与茧层率、五龄前3天净增体重和摄食系数、三龄眠蚕体重存在着极显著的相关关系。  相似文献   

The effect of diet type on the plasma disposition of triclabendazole in goats     

Gokbulut C  Karademir U  Boyacioglu M  Akar F 《Research in veterinary science》2007,82(3):388-391

The effect of two different diet types (concentrate feed+hay and grazing) on the pharmacokinetic profiles of triclabendazole following oral administration in goats was investigated. A total of 12 goats were randomly allocated into two groups which were either indoor and fed concentrate + hay ration (housed group) or were grazing on pasture (grazing group). Triclabendazole was administered orally to animals in two groups at 10 mg/kg bodyweight. Blood samples were collected from 1 h to 192 h post-treatment and analyzed by high performance liquid chromatography (HPLC). Feeding with different diets significantly effected the plasma disposition of triclabendazole sulphoxide. Maximum plasma concentration (C(max): 13.22+/-2.81 microg/ml), time to reach maximum plasma concentration (t(max): 18.4+/-2.19 h), area under the curve (AUC: 613+/-137 microg h/ml), half-life (t(1/2): 24.77+/-1.94 h) and mean resident time (MRT: 40.22+/-4.36 h) of triclabendazole sulphoxide in housed group were significantly different from those of grazing group (C(max): 10.17+/-1.51 microg/ml, t(max): 14.0+/-2.19 h, AUC: 406+/-98 microg h/ml), t(1/2): 16.16+/-1.17 h and MRT: 34.48+/-4.40 h). It is concluded that anthelmintically more active sulphoxide metabolite has higher plasma concentration when triclabendazole is administered to goats fed with concentrate feed + hay compared to grazing goats.  相似文献   

内蒙古荒漠草原主要草食动物食性及其营养生态位     

刘贵河  王国杰  汪诗平  韩建国  宛新荣  郝树广 《勤云标准版测试》2013,33(3):856-866

为探讨荒漠草原主要食草动物(绵羊、达乌尔黄鼠和亚洲小车蝗)的食性及其种间生态位变化与草原退化的关系,以内蒙古苏尼特右旗荒漠草原为研究对象,于2003年7-8月运用饱和链烷技术研究小针茅群落不同放牧强度下绵羊、达乌尔黄鼠和亚洲小车蝗的食性及其生态位变化.结果表明:随牧压的增大,群落中小针茅数量显著减少,猪毛菜比例随着增加;绵羊、达乌尔黄鼠、亚洲小车蝗3种食草动物的主要食物均来源于猪毛菜,且采食比例随牧压增大而递增;3种食草动物对牧草的选择性指数随牧压的变化而变化,双齿葱和多根葱优先被采食;三者生态位重叠程度很高且生态位宽度随牧压的增加而变窄.重度放牧改变了小针茅群落的植物组成,使其演替为猪毛菜群落,3种食草动物对草地资源存在激烈的竞争,因此,控制鼠、虫的种群密度,防止鼠、虫害的发生对保证放牧家畜的食物安全具有十分重要的现实意义.  相似文献   

不同蛋白水平日粮对狼山鸡卵黄中激素沉积及子代生长的影响     

陈磊  饶开晴  杨晓静  陈杰  赵茹茜 《勤云标准版测试》2007,(7)

选取狼山鸡种母鸡160羽,随机分成三个组,分别饲喂粗蛋白水平为10%(低)、15%(对照)和20%(高)的日粮,21d后收集种蛋。每组随机选择10枚种蛋用于放免测定卵黄中母源性甲状腺激素和胰高血糖素,其余孵化后在相同条件饲养至28d,并测定生长性能.。分别与1日龄和28日龄每组各选10羽雏鸡进行屠宰测定。结果:(1)试验前后母鸡体重各组间均没有变化,低蛋白组产蛋率和蛋重显著下降(p<0.05),高蛋白组蛋重显著高于对照组;(2)三组种蛋的卵黄中T3、胰高血糖素水平均没有显著性差异,而高蛋白组卵黄中T4水平显著高于对照组和低蛋白组(p<0.05),低蛋白组1d后代血清中T3水平显著高于对照组,而高蛋白组血清T4水平显著高于对照组(p<0.05);(3)出雏重与蛋重呈正相关(R2=0.9275,p<0.01),出雏后高、低蛋白组子代均表现出较高的生长速度,28d低蛋白组子代鸡体重和相对胸肌重显著高于对照组(p<0.05),高蛋白组体重与对照组相比有增加趋势,但差异不显著(p=0.08)。结论:母鸡饲喂不同蛋白水平日粮可以改变卵黄中母源性激素的沉积并能显著影响子代的生长。  相似文献   

Habitat use of ponies and cattle foraging together in a coastal dune area     

Indra Lamoot  Carolien Meert 《Biological conservation》2005,122(4):523-536

Grazing by large ungulates has been chosen as a management tool in scrub-dominated dune reserves at the Belgian coast. Due to morphological and physiological differences between cattle and ponies, differences in foraging behaviour and habitat use are expected, and these may result in a different impact on the spatially heterogeneous and nutrient-limited ecosystem. Grazing behaviour and habitat use of Shetland ponies and Highland cattle, grazing together in a coastal dune area (60 ha) were investigated at various levels of the foraging hierarchy (habitat, vegetation type, sward height and diet). Habitat use overlap was high in all seasons; both cattle and pony spent most of their grazing time in the grass-dominated habitat. However, Shetland ponies concentrated their grazing activity more on the grass-dominated habitat than did cattle. Cattle spent a greater proportion of their grazing activity in woodland and scrub, compared to the ponies. Foraging activity in woodland and scrub is strongly influenced by season. Within the grass-dominated habitat both species preferred foraging in the grasslands and avoided open vegetation and moss dunes. Within the grasslands, cattle grazed less on the short swards than did ponies. Both cattle and ponies predominantly foraged on graminoids, though there are minor differences between both species and among seasons. Browsing of woody plants occurred only by cattle. Where grazing management has been implemented to maintain dune grasslands and to avoid further invasion by scrub, a combination of cattle and ponies appears to be adequate. Ponies are suitable for maintaining grasslands, but they have no impact on invading scrub. Cattle have an impact on scrub development, both by direct consumption of various shrub species and by opening initially closed scrub.  相似文献   

Whole grain phytochemicals and health   总被引：13，自引：0，他引：13  

Rui Hai Liu   《Journal of Cereal Science》2007,46(3):207

Phytochemicals and antioxidants in whole grains have not received as much attention as the phytochemicals in fruits and vegetables although the increased consumption of whole grains and whole grain products has been associated with reduced risk of developing chronic diseases such as cardiovascular disease, type 2 diabetes, some cancers and all-cause mortality. Recent research has shown that the total phytochemical content and antioxidant activity of whole grains have been commonly underestimated in the literature, and that whole grains contain more phytochemicals than was previously reported. Most whole grain phenolics are in bound form, 85% in corn, 76% in wheat, and 75% in oats. In addition, whole grains contain unique phytochemicals that complement those in fruits and vegetables when consumed together. The beneficial effects associated with whole grain consumption are in part due to the existence of the unique phytochemicals of whole grains. The majority of phytochemicals of whole grains that are beneficial for health are present in the bran/germ fraction. In whole wheat flour, the bran/germ fraction contributed 83% of total phenolic content, 79% of total flavonoid content, 78% of total zeaxanthin, 51% of total lutein, and 42% of total β-cryptoxanthin. The bran/germ fraction of whole wheat may therefore impart greater health benefits when consumed as part of a diet, and help reduce the risk of chronic diseases. This paper will review recent research on the phytochemicals and antioxidant activity of whole grains and their unique contribution to the health benefits of whole grains.  相似文献   

玉米螟杀虫剂的室内筛选     

罗兰  于毅  袁忠林  徐艺伟  李丽莉 《安徽农业科学》2013,(31):12326-12327,12341

[目的]筛选对玉米螟幼虫和卵具有较好毒杀作用的药剂,为玉米螟的化学防治提供科学依据。[方法]采用人工饲料混药法和浸渍法分别测定10种杀虫剂对玉米螟幼虫和卵的毒杀作用。[结果]印楝素、甲维盐和氯虫苯甲酰胺对玉米螟幼虫具有较高毒力,对3龄幼虫的加50值分别为0．0006,0．0250和0．0387mg／L;印楝素浓度为10．0mg／L时,卵的孵化率为17．80％。[结论]印楝素、甲维盐和氯虫苯甲酰胺可作为玉米螟的防治药剂。  相似文献