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31.
Interactions between climatic and production factors on returns of female pigs to service during summer in Japanese commercial breeding herds 总被引:1,自引:0,他引:1
The objectives of this study were to determine the associations between climatic factors and production factors for returns to service of female pigs during summer and to quantify the associations between these factors and occurrences of returns to service. The factors that were assessed were as follows: maximum temperature (HT), relative humidity, age of gilts at first mating, parity, weaning-to-first-mating interval (WMI), and lactation length. The study analyzed records of 18,307 gilts in 99 herds and 78,135 parity records of 56,322 sows in 103 herds; all the females were first-serviced between June and September, 2007 to 2009. Average daily HT and relative humidity for 15 days post-service of a female were obtained from 21 local weather stations and coordinated with the performance data of the respective local herds. The returns to service were categorized into three groups: regular returns (RRs: 18–24 days), irregular returns (IRs: 25–38 days), and late returns to service (LRs: 39 days or later). Two-level mixed-effects models were applied to the data by using a herd at level 2 and an individual record at level 1. In mated gilts, the occurrences (%) of RRs, IRs, and LRs were 4.8%, 1.8%, and 5.3%, respectively. In mated sows, the respective occurrences were 3.3%, 1.8%, and 4.2%. Mean values (ranges) of HT and relative humidity were 28.4 °C (13.6 °C–39.8 °C) and 73.4% (35.0%–98.0%), respectively. In gilts, as HT increased from 25 °C to 30 °C, the occurrence of RR increased from 3.7% to 4.4% (P < 0.05). However, there was no association between the occurrence of RR and either relative humidity (P = 0.17) or age at first mating (P = 0.23). In addition, there were no associations between the occurrences of either gilt IR or LR and HT (P ≥ 0.05), relative humidity (P ≥ 0.46), or age at first mating (P ≥ 0.32). In sows, greater occurrences of RRs, IRs, and LRs were associated with higher HT, lower parity, and a WMI of 7 days or longer (P < 0.05), but they were not associated with relative humidity (P ≥ 0.62) or lactation length (P ≥ 0.13). The occurrence of RRs in sows of all WMI groups increased 1.22 (1.045) times for each 5 °C increase in HT. For sows with WMI 0 to 6 days, each 5 °C rise in HT increased the occurrence of IRs and LRs by 1.36 (1.065) and 1.27 (1.055) times, respectively. However, there was no association between increased HT and occurrences of IRs or LRs for sows with WMI 7 days or longer (P ≥ 0.38). Therefore, in order to prevent returns to service, it is recommended that producers apply cooling management for females during the post-service periods in summer. 相似文献
32.
Judith A H Wodke Maria Lluch‐Senar Josep Marcos Eva Yus Miguel Godinho Ricardo Gutiérrez‐Gallego Vitor A P Martins dos Santos Luis Serrano Edda Klipp Tobias Maier 《Molecular systems biology》2013,9(1)
Mycoplasma pneumoniae, a threatening pathogen with a minimal genome, is a model organism for bacterial systems biology for which substantial experimental information is available. With the goal of understanding the complex interactions underlying its metabolism, we analyzed and characterized the metabolic network of M. pneumoniae in great detail, integrating data from different omics analyses under a range of conditions into a constraint‐based model backbone. Iterating model predictions, hypothesis generation, experimental testing, and model refinement, we accurately curated the network and quantitatively explored the energy metabolism. In contrast to other bacteria, M. pneumoniae uses most of its energy for maintenance tasks instead of growth. We show that in highly linear networks the prediction of flux distributions for different growth times allows analysis of time‐dependent changes, albeit using a static model. By performing an in silico knock‐out study as well as analyzing flux distributions in single and double mutant phenotypes, we demonstrated that the model accurately represents the metabolism of M. pneumoniae. The experimentally validated model provides a solid basis for understanding its metabolic regulatory mechanisms. 相似文献
33.
Chunyan Chen Tian Shen Fei Tian Ping Lin Qingtian Li Zelin Cui Yajuan Zhang Min Xue Jing Ye Xiaokui Guo YuhuaZhou 《Acta biochimica et biophysica Sinica》2013,(12):1039-1048
Community-acquired pneumonia (CAP) is a major concern in hospitals and the bacterial community of which has not been systemically discussed yet. Sputum from patients in the acute stages is a kind of accessible sample reflecting its fea- tures. In our study, we analyzed 45 sputum samples from 45 patients with CAP. Eighteen sputum samples from healthy people were chosen as the controls. Pyrosequencing of the 16s rDNA V3 hypervariable regions of aH the bacteria con- tained in the sputum was used as a culture-independent method to disclose the community constitution. Also, our published data for hospital-acquired pneumonia (HAP) in sputum was used for comparison. By pyrosequencing, 〉90,000 DNA reads were detected. After being analyzed by tools in the Ribosomal Database Project, the reads were clas- sified into five main phyla and 〉100 genera. At the phyla level, the reads' distribution of CAP is similar to that of healthy people and at genera level, the occurrence of each genus possesses their feature in three categories. Genera such as Streptococcus and Neisseria showed stability in their percentages, indicating that such genera are rarely affected by exogenous bacteria or antibiotics. The role of other genera such as Moraxella and Rothia in CAP should be emphasized. According to our analysis, the bacterial communities of CAP are with slight change when compared with those of healthy people, but have a large gap between HAP. Meanwhile, Rothia might be an important endogenous pneumonia-causing factor. 相似文献
34.
目的:探讨参麦注射液与布地奈德联合治疗急性酒精中毒伴吸入性肺炎的临床疗效及对肝功能和炎症指标的影响。方法:选择2014年3月至2015年8月在我院接受治疗的120例急性酒精中毒伴吸入性肺炎患者为研究对象,按照随机数字表法分为治疗组和对照组,每组60例患者,对照组给予布地奈德治疗,治疗组在对照组的基础上给予参麦注射液治疗,观察两组患者的临床疗效、症状消失时间、肝功能及血清肿瘤坏死因子-α、IL-6和IL-8炎性细胞因子的变化。结果:治疗组的总有效率为95.00%显著高于对照组的83.00%,差异有统计学意义(X~2=-4.227,P=0.039)。治疗组的哮鸣音、湿罗音、咳嗽和气喘消失时间明显短于对照组,差异有统计学意义(P0.005)。治疗组的肝功能ALT、AsT和GGT明显改善,炎性因子TNF-α、IL-6和IL-8水平下降明显,差异均有统计学意义(P0.005)。结论:参麦注射液与布地奈德联合治疗急性酒精中毒伴吸入性肺炎疗效确切,可以有效缩短患者的症状消失时间,改善肝功能,减轻炎症反应,值得临床推广应用。 相似文献
35.
目的:探讨纤维支气管镜对急诊重症肺炎合并呼吸衰竭患者呼吸功能及炎症反应的影响。方法:选择2013年9月-2015年9月在我院接受治疗的重症肺炎合并呼吸衰竭患者89例作为研究对象,根据治疗方法不同,将患者分为研究组(47例)与对照组(42例)。对照组患者采用常规抗感染治疗,研究组患者在对照组基础上采用纤维支气管镜肺泡灌洗治疗。观察并比较两组患者治疗前后的动态顺应性(Cdyn)、氧合指数(Pa O2/Fi O2)、呼吸做功(WOB)、血清炎症因子水平的变化情况。结果:治疗前,两组患者Cdyn,WOB,Pa O2/Fi O2,CD11b+中性粒细胞、STREM-1及HMGB-1水平比较,差异均无统计学意义(P0.05);治疗后,对照组患者Cdyn、Pa O2/Fi O2及WOB均较治疗前显著升高,差异具有统计学意义(P0.05);研究组患者Cdyn及Pa O2/Fi O2较治疗前显著升高,而WOB较治疗前显著降低,差异具有统计学意义(P0.05);研究组患者Cdyn及Pa O2/Fi O2高于对照组,而WOB低于对照组,差异具有统计学意义(P0.05);两组患者CD11b+中性粒细胞、STREM-1及HMGB-1水平均较治疗前显著降低,且研究组显著低于对照组,差异均具有统计学意义(P0.05)。结论:纤维支气管镜肺泡灌洗能够改善急诊重症肺炎合并呼吸衰竭患者的呼吸功能,缓解机体炎症反应,具有重要的临床意义。 相似文献
36.
目的:探讨小儿肺热咳喘口服液联合阿奇霉素对肺炎支原体肺炎患儿肺功能和炎性因子的影响。方法:选取2016年1月~2017年12月期间我院收治的175例肺炎支原体肺炎患儿,根据随机数字表法将其分为对照组(n=87,阿奇霉素治疗)和研究组(n=88,小儿肺热咳喘口服液联合阿奇霉素治疗),比较两组患儿临床疗效、临床症状消失时间、肺功能指标[第1s用力呼气容积(FEV1)、用力肺活量(FVC)、FEV1/FVC]、炎性因子指标[肿瘤坏死因子-α(TNF-α)、白介素-6(IL-6)、C反应蛋白(CRP)],记录两组患儿不良反应发生情况。结果:研究组患儿治疗后临床总有效率为94.32%(83/88),高于对照组患儿的80.46%(70/87)(P0.05)。研究组患儿咳嗽、发热、湿啰音、哮鸣音的消失时间均短于对照组(P0.05)。两组患儿治疗后FEV1、FVC、FEV1/FVC均升高,且研究组高于对照组(P0.05)。两组患儿治疗后IL-6、CRP、TNF-α水平均降低,且研究组低于对照组(P0.05)。两组患儿不良反应发生率对比无统计学差异(P0.05)。结论:小儿肺热咳喘口服液联合阿奇霉素治疗肺炎支原体肺炎患儿的疗效优于单用阿奇霉素,且可有效改善患儿肺功能和炎性因子水平,快速缓解临床症状,促进患儿恢复。 相似文献
37.
目的:分析和比较酚妥拉明联合多巴酚丁胺与多巴胺治疗重症肺炎患儿的有效性及安全性。方法:选取2014年4月至2019年4月西安交通大学附属儿童医院急诊科收治的96例重症肺炎患儿,根据入院单双号将其分为对照组(n=48)和研究组(n=48)。对照组接受多巴酚丁胺与小剂量多巴胺治疗,研究组在对照组的基础上联合酚妥拉明治疗。比较两组的治疗总有效率、治疗前后各血气指标与炎性因子水平变化以及不良反应的发生情况。结果:治疗后,研究组总有效率显著高于对照组(93.75%vs.79.17%,P0.05);两组的血气指标PaO2、SaO2均显著升高,PaCO2显著降低,且研究组的变化比对照更加显著(P0.05);两组各的炎性因子水平IL-6、IL-8、CRP和TNF-α均显著降低,且研究组显著低于对照组(P0.05)。两组不良反应发生率比较无统计学差异(P0.05)。结论:酚妥拉明联合多巴酚丁胺治疗重症肺炎患儿的临床疗效明显优于酚妥拉明联合多巴胺治疗,且二者安全性相当。 相似文献
38.
Roshan Dsouza Darold R. Spillman Ronit Barkalifa Guillermo L. Monroy Eric J. Chaney Karen C. White Stephen A. Boppart 《Journal of biophotonics》2019,12(5)
The formation of biofilms in the endotracheal tubes (ETTs) of intubated patients on mechanical ventilation is associated with a greater risk of ventilator‐associated pneumonia and death. New technologies are needed to detect and monitor ETTs in vivo for the presence of these biofilms. Longitudinal OCT imaging was performed in mechanically ventilated subjects at 24‐hour intervals until extubation to detect the formation and temporal changes of in vivo ETT biofilms. OCT‐derived attenuation coefficient images were used to differentiate between mucus and biofilm. Extubated ETTs were examined with optical and electron microscopy, and all imaging results were correlated with standard‐of‐care clinical test reports. OCT and attenuation coefficient images from four subjects were positive for ETT biofilms and were negative for two subjects. The processed and stained extubated ETTs and clinical reports confirmed the presence/absence of biofilms in all subjects. Our findings confirm that OCT can detect and differentiate between biofilm‐positive and biofilm‐negative groups (P < 10?5). OCT image‐based features may serve as biomarkers for direct in vivo detection of ETT biofilms and help drive investigation of new management strategies to reduce the incidence of VAP. 相似文献
39.
《Animal : an international journal of animal bioscience》2022,16(11):100659
Using agricultural by-products such as dehydrated orange pulp (DOP) in animal feeds is of interest to increase pig sector sustainability. With this aim, an assay was carried out to assess the effects of increasing inclusion levels of DOP in pig diets regarding animal performance, carcass quality, and environmental impact. Four experimental diets were designed, a control diet (T1) and three more diets with increasing levels of DOP with 80, 160, and 240 g/kg of DOP for diets T2, T3, and T4, respectively. One hundred and sixty growing pigs were used in the experiment. Growth performance (average daily gain, ADG; average daily feed intake, ADFI and feed conversion ratio, FCR) and in vivo backfat thickness (BF) and loin depth (LD) gain were recorded during the finishing phase (from 70 to 130 kg BW). Faecal samples were incubated for bacteria enumeration. At slaughter, carcass characteristics and meat quality traits were measured, and subcutaneous fat was sampled to analyse the fatty acid (FA) profile. Additionally, the slurry excreted by the animals was measured, characterised and subjected to a gaseous emission assay during its storage. The final BW and overall ADFI, ADG and FCR were similar among treatments. In vivo final LD and BF gain decreased (P ≤ 0.10) as the inclusion level of DOP increased. No differences were observed in carcass characteristics with the inclusion of DOP, except carcass weight that decreased linearly (P = 0.05) with DOP. Regarding the FA profile of the subcutaneous fat, the ratio of total monounsaturated to saturated FA increased with the inclusion level of DOP. Neither slurry excretion and characterisation nor bacterial counts from faeces showed any significant difference among treatments. The inclusion of DOP led to greater CH4 emissions in mg per L of slurry and hour, whereas these differences disappeared when expressed in mg per animal and day. In all, it has been demonstrated that the inclusion of DOP up to 240 mg/kg in pig diets had minor effects on growth performance, carcass quality traits or gaseous emissions from slurry, favouring the circular economy strategy and pig sector sustainability. 相似文献
40.
目的:观察硝黄散外敷联合加味五虎汤口服治疗痰热闭肺型肺炎支原体肺炎(MPP)患儿对肺功能和血清肿瘤坏死因子-α(TNF-α)、γ-干扰素(IFN-γ)、白介素-4(IL-4)水平的影响。方法:研究对象为我院2019年6月~2021年1月期间收治的MPP患儿80例,采用随机数字表法将患儿分为对照组(n=40,阿奇霉素抗感染治疗)和研究组(n=40,对照组基础上加用硝黄散外敷联合加味五虎汤口服治疗),均治疗7 d。比较两组患儿临床疗效,比较两组治疗前、治疗7 d后的中医证候积分、临床症状改善情况、肺功能和血清TNF-α、IFN-γ、IL-4水平。结果:研究组治疗7 d后的临床总有效率为92.50%(37/40),高于对照组的72.50%(29/40),差异有统计学意义(P<0.05)。与对照组相比,研究组的症状(咳嗽憋喘、发热、肺部干湿啰音)消失时间均更短(P<0.05)。与对照组相比,研究组治疗7 d后用力肺活量(FVC)、最高呼气峰流速(PEF)、第1秒最大呼气容积(FEV1)、FEV1/FVC均更高(P<0.05),研究组治疗7 d后的中医证候积分及血清TNF-α、IFN-γ和IL-4水平均更低(P<0.05)。结论:痰热闭肺型MPP患儿采用硝黄散外敷联合加味五虎汤口服治疗,可有效缩短患儿症状消失时间,显著改善其肺功能、血清炎症因子水平,疗效显著。 相似文献