Strong functional stability of soil microbial communities under semiarid Mediterranean conditions and subjected to long-term shifts in baseline precipitation     

《Soil biology & biochemistry》2014

We investigated the effect of soil microclimate on the structure and functioning of soil microbial communities in a Mediterranean Holm-oak forest subjected to 10 years of partial rain exclusion manipulations, simulating average drought conditions expected in Mediterranean areas for the following decades. We applied a high throughput DNA pyrosequencing technique coupled to parallel measurements of microbial respiration (R_H) and temperature sensitivity of microbial respiration (Q₁₀). Some consistent changes in the structure of bacterial communities suggest a slow process of community shifts parallel to the trend towards oligotrophy in response to long-term droughts. However, the structure of bacterial communities was mainly determined by short-term environmental fluctuations associated with sampling date (winter, spring and summer) rather than long-term (10 years) shifts in baseline precipitation. Moreover, long-term drought did not exert any chronic effect on the functioning of soil microbial communities (R_H and Q₁₀), emphasizing the functional stability of these communities to this long-term but mild shifts in water availability. We hypothesize that the particular conditions of the Mediterranean climate with strong seasonal shifts in both temperature and soil water availability but also characterized by very extreme environmental conditions during summer, was acting as a strong force in community assembling, selecting phenotypes adapted to the semiarid conditions characterizing Mediterranean ecosystems. Relations of climate with the phylogenetic structure and overall diversity of the communities as well as the distribution of the individual responses of different lineages (genera) to climate confirmed our hypotheses, evidencing communities dominated by thermotolerant and drought-tolerant phenotypes.  相似文献   

猪胆囊中沙门菌L型的分离培养与invA基因检测     

佘晓玲  王涛  丁文静  吴文娟  潘耀振  汤可立  王丹霓  王和 《动物医学进展》2015,(3):25-28

为了解猪胆囊中沙门菌L型携带情况,在贵阳市屠宰场采集970例健康生猪的胆囊组织与胆汁标本,用常规细菌学方法和非高渗分离培养法分离沙门菌及其细菌L型,用PCR和核酸序列分析方法对稳定L型纯培养物进行沙门菌的invA基因检测。结果显示,970例生猪胆囊标本未检出沙门菌细菌型,细菌L型检出率为8.25%;80例细菌L型分离物中有50例invA检测阳性,占5.15%;占细菌L型阳性分离物62.50%。研究结果为生猪胆囊沙门菌L型感染的流行病学及其检查提供了依据。  相似文献   

Analysis of Inter-Individual Bacterial Variation in Gut of Cicada Meimuna mongolica (Hemiptera: Cicadidae)     

Wenting Zhou  Xiaoning Nan  Zhou Zheng  Cong Wei  Hong He 《Journal of insect science (Online)》2015,15(1)

Intestinal bacterial community plays a crucial role in the nutrition, development, survival, and reproduction of insects. When compared with other insects with piercing-sucking mouthparts, the habitats of cicada nymphs and adults are totally different. However, little is known about the differences in the gut bacterial communities in the nymphs and adults within any cicada species. The diversity of bacteria in the gut of nymphs and adults of both genders of Meimuna mongolica (Distant) was studied using the denaturing gradient gel electrophoresis (DGGE) method. Few inter-individual variations among gut microbiota were observed, suggesting that M. mongolica typically harbors a limited and consistent suite of bacterial species. Bacteria in the genera Pseudomonas and Enterobacter were the predominant components of the gut microflora of M. mongolica at all life stages. Bacteria of Pantoea, Streptococcus, and Uruburuella were also widespread in the cicada samples but at relatively lower concentrations. The relative stability and similarity of the PCR-DGGE patterns indicate that all individuals of this cicada species harbor a characteristic bacterial community which is independent from developmental stages and genders. Related endosymbionts that could be harbored in bacteromes of cicadas were not detected in any gut samples, which could be related to the cicada species and the distribution of these endosymbionts in the cicada cavity, or due to some of the possible limitations of PCR-DGGE community profiling. It is worthwhile to further address if related cicada endosymbiont clades distribute in the alimentary canals and other internal organs through diagnostic PCR using group-specific primer sets.  相似文献   

The importance of manual white blood cell differential counts and platelet estimates in elephant hematology: blood film review is essential     

Tatiana C. Weisbrod  Ramiro Isaza  Carolyn Cray  Laurie Adler  Nicole I. Stacy 《The Veterinary quarterly》2021,41(1):30

Unique features of elephant hematology are known challenges in analytical methodology like two types of monocytes typical for members of the Order Afrotheria and platelet counts of the comparatively small elephant platelet. To investigate WBC differential and platelet data generated by an impedance-based hematology analyzer without availability of validated species-specific software for recognition of elephant WBCs and platelets, compared to manual blood film review. Blood samples preserved in ethylenediaminetetraacetic acid (EDTA) of 50 elephants (n = 35 Elephas maximus and n = 15 Loxodonta africana) were used. A Mann-Whitney test for independent samples was used to compare parameters between methods and agreement was tested using Bland-Altman bias plots. All hematological variables, including absolute numbers of heterophils, lymphocytes, monocytes, eosinophils, basophils, and platelets, were significantly different (p < 0.0001) between both methods of analysis, and there was no agreement using Bland-Altman bias plots. Manual review consistently produced higher heterophil and monocyte counts as well as platelet estimates, while the automated analyzer produced higher lymphocyte, eosinophil, and basophil counts. The hematology analyzer did not properly differentiate elephant lymphocytes and monocytes, and did not accurately count elephant platelets. These findings emphasize the importance of manual blood film review as part of elephant complete blood counts in both clinical and research settings and as a basis for the development of hematological reference intervals.  相似文献   

Platelet abnormalities and platelet-to-lymphocyte ratios in canine immunosuppressant-responsive and non-responsive enteropathy: A retrospective study in 41 dogs     

Alessio PIERINI  Giada ESPOSITO  Eleonora GORI  Elena BENVENUTI  Pietro RUGGIERO  George LUBAS  Veronica MARCHETTI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(2):248

Few studies have examined platelet alterations in dogs with chronic enteropathy. Our aim was to investigate platelet count (PLT), mean platelet volume (MPV), and platelet-to-lymphocyte ratio (PLR) in dogs diagnosed with immunosuppressant-responsive enteropathy (IRE). In this retrospective study of 41 dogs, data regarding signalment, canine chronic enteropathy clinical activity index (CCECAI), endoscopic and histopathological scores, PLT, MPV, PLR, total serum protein concentrations, albumin, and iron were collected. Clinical response and relapse were assessed with the evaluation of CCECAI over time. One month after starting therapy, dogs with >25% CCECAI reduction were considered responders. During a three-month CCECAI evaluation as part of a twelve-month follow-up, a CCECAI >3 together with a ≥2 unit increase in responder dogs was considered a relapse. PLT and PLR displayed significant negative correlation with MPV. MPV was positively correlated with total protein and albumin levels and negatively correlated with CCECAI. Three dogs were classified as non-responders, and 14 relapsed within 12 months. No differences were observed in PLT, MPV, or PLR between responding/non-responding and relapsing/non-relapsing groups. PLT, MPV, and PLR correlated with total protein, albumin, and CCECAI, confirming PLT as a potential marker, and suggesting MPV as a new marker of clinical efficacy against canine IRE.  相似文献   

Adjusted method of penis fixation during boar semi-automatic semen collection aiming to reduce bacterial contamination     

Aline Fernanda Lopes Paschoal  Ana Paula Gonçalves Mellagi  Cristina Vicenti Ferrari  Karine Ludwig Takeuti  Gabriela da Silva Oliveira  Mari Lourdes Bernardi  Rafael da Rosa Ulguim  Fernando Pandolfo Bortolozzo 《Reproduction in domestic animals》2021,56(6):897-904

Semen collection has an essential role in the initial bacterial load in boar ejaculates and extended semen. The study aimed to explore the efficacy of an adjusted penis fixation in a semi-automatic collection system on reducing bacterial contamination of ejaculates in two-boar studs with different scenarios. Historically, stud A had low levels of bacterial load in raw semen, while stud B had a high level of contamination. A total of 56 mature boars had their semen collected using two methods of penis fixation: (a) Traditional: The penis was fixed directly with the artificial cervix and transferred to the adjustable clamp; (b) Adjusted: The fixation was performed with one gloved-hand, and after exteriorization, the penis was gripped using the artificial cervix with the other gloved-hand and transferred to the adjustable clamp. The bacterial load (p = .0045) and the occurrence of ejaculates >231 CFU/ml (p = .0101) were reduced in the Adjusted compared to the Traditional method. Bacterial load was reduced when using the Adjusted method in stud B (p = .0011), which showed a greater occurrence of critical factors for bacterial contamination (p ≤ .0034). The Adjusted method reduced the occurrence of ejaculates >231 CFU/ml when the preputial ostium was dirty (p = .016) and the duration of semen collection was >7 min (p = .022) compared to the Traditional method. In conclusion, the Adjusted penis fixation was efficient in reducing bacterial load of ejaculates, mainly in boar stud B, which had high contamination challenges.  相似文献   

祁连山不同类型草地土壤细菌群落特征研究     

赵文  尹亚丽  李世雄  刘燕  刘晶晶  董怡玲  苏世锋  吉凌鹤 《草业学报》2021,30(12):161-171

祁连山是我国西部重要的生态屏障,拥有大量的草地资源。研究草地土壤细菌群落组成及其与土壤环境因子间的关系,可对维持草地生态及了解祁连山土壤细菌群落组成提供一定的数据基础。采用高通量测序技术检测并分析了祁连山默勒镇3种类型草地 （高寒草甸、人工草地、沼泽化草甸）0~10 cm土壤细菌群落结构及多样性,并对上述土壤细菌群落与土壤理化因子的相关性进行了系统的研究。结果表明：1）沼泽化草甸土壤全氮、全磷、有机质碳、含水量和硝态氮显著高于高寒草甸和人工草地（P<0.05）。2）3地共测得有效序列1022446条,以97%的一致性将序列聚类,高寒草甸、人工草地、沼泽化草甸OTU聚类均值分别是4917、5233、5075条。3）Shannon和Simpson多样性指数3地间差异不显著,Chao1指数表现为人工草地>高寒草甸>沼泽化草甸（P<0.05）。4）在门水平上,3地均以变形菌门、酸杆菌门、放线菌门和浮霉菌门为主要类群;在属水平上,表现出不同类型草地细菌富集类型不同。5）有机质碳、全磷、土壤含水量与土壤细菌群落的组成表现出极显著相关（P<0.01）。综上,祁连山地区小生境内3种草地土壤微生物群落存在差异,有机质碳、全磷、土壤含水量是影响群落的主要驱动因子。  相似文献   

Screening of Probiotics Inhibiting E. coli K88 in vitro     

WANG Lei  LV Yang  ZHANG Yue  XIE Jia-qian  ZHAO Di  YAN Li-qiong  MEI Hui-min  WANG Lei  YI Dan  CHEN Hong-bo  DING Bin-ying  HOU Yong-qing  WU Tao 《中国畜牧兽医》2016,43(5):1355-1360

The probiotics tested in the experiment were isolated from the intestinal of weaning piglets.The isolated probiotics and E.coli K88 were inoculated into the culture of intestinal porcine epithelial cell-1 (IPEC-1).The activity of lactate dehydrogenase (LDH) in the supernatant was measured after incubating for 2.5 h.At the same time, the probiotics and E.coli K88 were co-cultured in vitro, the number of E.coli K88 was counted and the probiotics which could be resistant to the E.coli K88 were selected 2.5 h later.The results showed that the Lactobacillus casei and Bacillus coagulans could significantly reduce LDH activity (P<0.05), decrease the damage of E.coli K88; Bacillus coagulans could inhibit the growth of E.coli K88.At the same time, Bacillus coagulans could resist high temperature, acid and bile salt.The results showed that Bacillus coagulans strains had great potential as the application of probiotics strains.The methods could be used as a model of screen probiotics which could inhibit the growth of E.coli K88 in vitro.  相似文献   

Acute‐phase proteins as diagnostic markers in horses with colic          下载免费PDF全文

Tina H. Pihl DVM  PhD  Elrien Scheepers BVSc  MSc  Macarena Sanz DVM  MS  DACVIM  Amelia Goddard BVSc  MMed Vet  Nils Toft Cand Sci  PhD  Mads Kjelgaard‐Hansen DVM  PhD  Pia H. Andersen DVM  PhD  DVSc  Stine Jacobsen DVM  PhD 《Journal of Veterinary Emergency and Critical Care》2016,26(5):664-674

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Molecular changes in the equine follicle in relation to variations in antral follicle count and anti‐Müllerian hormone concentrations          下载免费PDF全文

A. Claes  B. A. Ball  M. H. T. Troedsson  T. E. Curry Jr.  E. L. Squires  K. E. Scoggin 《Equine veterinary journal》2016,48(6):741-748

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