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1.
This study aimed to investigate whether Escherichia coli endotoxin (LPS) may predispose the lung to an infection with Pasteurella multocida type A (Pma) and to determine the LPS concentration needed to reproduce clinical signs of bronchopneumonia. Twenty-four hours before inoculating Pma or sterile growth medium, piglets were tracheally instilled with 10, 100 or 400 microg/kg LPS. Cough, body temperature, daily weight gain (DWG) bronchoalveolar lavage fluid (BALF) cells and volume of pneumonic lung were measured. Changes in breathing pattern (Penh) were assessed by whole body barometric plethysmography. No significant changes were observed in Pma-treated or in control animals. Each LPS doses induced DWG reduction while the higher generated a severe subacute interstitial pneumonia causing hyperthermia and an increase in Penh. The combination of the lower LPS doses with Pma produced an asymptomatic bronchopneumonia leading to DWG reduction, rise in Penh and an increase in BALF macrophages and neutrophils. With 400 microg/kg LPS, Pma worsened the inflammatory process as illustrated by cough, hyperthermia, major DWG reduction and by a greater Penh response. Lung lesions consisted of severe exudative bronchopneumonia. We concluded that LPS may negatively influence growth, predispose to persisting lung inflammatory process and promote Pma infection depending on the dose previously administered.  相似文献   

2.
The aim of this work was to investigate whether the Penh index, measured using whole body barometric plethysmography, can be used as a screening parameter to evaluate the airway reactivity and the intensity of the pulmonary response to endotoxins. Penh was firstly recorded in non-sedated freely moving piglets exposed (1) to a nebulized acetylcholine (Ach) pre-treated or not with clenbuterol, or (2) to endotoxin challenge. To measure Penh simultaneously with total pulmonary resistance (R(L)), dynamic compliance (C(dyn)) and intrapleural pressure changes (Max Delta Ppl), an oesophageal balloon catheter technique was used and the piglets were anaesthetised. The recordings were performed during (1) an intravenous metacholine (Mch) challenge and (2) in endotoxin-exposed animals. In freely moving animals, Ach induced a significant dose-dependent increase in Penh, which was significantly blocked by clenbuterol. Endotoxin instillation also resulted in a significant rise in Penh while the corresponding response measured under anaesthesia was significantly and positively correlated with R(L) and Max Delta Ppl. Similar results were obtained during Mch challenge but the Penh was negatively correlated with C(dyn). We conclude that Penh could be used in freely moving piglets as a screening index for airway reactivity and pulmonary functional changes in cholinergic and endotoxin challenges.  相似文献   

3.
Five 6-month-old calves were inoculated with bovine viral diarrhea (BVD) virus (n = 3) or Pasteurella haemolytica (n = 2) endobronchially with a fiberoptic bronchoscope. Five additional calves were inoculated sequentially with BVD virus followed by P haemolytica at a 5-day interval. Blood samples were collected daily from the calves for bacterial isolation. Clinical signs of respiratory tract disease in calves were recorded daily. If the calves survived, they were killed for necropsy 3 or 4 days after inoculation with P haemolytica (or 8 days after inoculation with BVD virus). The extent and nature of pulmonary lesions in the calves were determined, and the lower portion of the respiratory tract (lungs and trachea) was examined for both these organisms. The 3 calves, inoculated with BVD virus only, developed mild clinical signs mainly manifested as fever, nasal discharge, and occasional cough. Approximately 2% to 7% of the total lung capacity of these calves was pneumonic. Mild clinical signs and localized lesions involving about 15% of the lung volume developed in the 2 calves exposed to P haemolytica only. However, severe fibrinopurulent bronchopneumonia and pleuritis involving 40% to 75% of lung volume developed in the 5 calves inoculated sequentially with BVD virus and P haemolytica. The possible role BVD virus may have in bovine respiratory tract disease is discussed.  相似文献   

4.
A commercial swine herd was selected for study, because pigs at slaughter repeatedly had lung lesions consistent with enzootic pneumonia and had snout lesions typical of atrophic rhinitis. Pigs born during various seasons of the year were allotted to 4 investigations and were evaluated from birth to slaughter. Individual lungs and snouts were identified and collected at the slaughter plant and later examined for gross lesions of bronchopneumonia and atrophic rhinitis, respectively. Each lesion was scored, and the following comparisons were made within investigations: prevalence and mean scores for lung lesions; prevalence and mean grades for snout lesions; correlations between lung lesion scores and growth indicators; correlations between snout lesion grades and growth indicators; and correlations between lung lesion scores and snout grade scores. Included in the growth indicators were average daily gain during the growing phase, average daily gain during the finishing phase, average daily gain during growing and finishing phases, and days to attain 104.5 kg of body weight. Prevalence of lung or snout lesions, mean values for lung lesion scores, mean values for snout lesion grades, and mean values for the various growth indicators were tested for statistical differences among the 4 investigations. Prevalence of lung lesions was highest (96%) for winter-slaughtered and lowest (81%) for autumn-slaughtered pigs. Mean scores for lung lesions were 7% (summer), 5% (autumn), 9% (winter), and 16% (spring). Prevalence of snout lesions was highest (85%) for spring-slaughtered pigs and lowest (42%) for autumn-slaughtered pigs.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

5.
Pasteurella multocida is a widespread respiratory pathogen in pigs associated with atrophic rhinitis and contributing to aggravation of the pulmonary lesions. The aims of the present study were to characterize isolates of P. multocida from porcine bronchopneumonia by pulsed-field gel electrophoresis (PFGE), PCR based capsular typing and multilocus sequence typing (MLST) and to compare clonal complexes outlined with the type of histological lung lesions to investigate if a correlation between clonal lineages and lesions might exist. Isolates of P. multocida were obtained from cases of cranioventrally located porcine bronchopneumonia. All lung lesions were described and classified according to histological lesions. A total of 139 isolates, from lung (n=111), pericardial sac (n=21) and kidney (n=7) of 111 pigs were described using PFGE with ApaI as the restriction enzyme. Furthermore, 20 and 29 isolates were characterized by capsular serotyping and multilocus sequence typing, respectively. PFGE demonstrated 15 different clusters showing 50% or more similarity. All selected isolates were of capsular serotype A and only three main sequence types (ST) were detected among the isolates. Associations were not found between histopathology and clonal complexes of P. multocida. In conclusion, PFGE demonstrated a high diversity of genotypes of P. multocida associated with porcine bronchopneumonia. However, isolates obtained mainly belonged to few STs, indicating that isolates of P. multocida associated with porcine bronchopneumonia originates from a limited number of clonal lineages and therefore might have adapted to porcine hosts. No correlation was demonstrated between genotypes and types of lesions, and extra-pulmonary spreading was only rarely demonstrated.  相似文献   

6.
副猪嗜血杆菌人工感染猪的病理学观察   总被引：7，自引：0，他引：7  
用副猪嗜血杆菌分离株感染断奶仔猪,发病仔猪临床表现为体温中度升高、精神不振、被毛粗乱、站立不稳、厌食、呼吸困难。尸体剖检,可见胸腹腔纤维素渗出严重,有大量的渗出液、肺出血及脑充血等;病理组织学表现为,肺脏、心脏、脾脏等脏器含有大量的中性粒细胞的纤维蛋白性多发性浆膜炎、脑膜炎及支气管肺炎。结果表明,此分离株为一高致病潜力的菌株。  相似文献   

7.
Three commercial swine herds were selected for study, because pigs at slaughter consistently had lung lesions typical of bronchopneumonia and snout lesions consistent with atrophic rhinitis. Pigs were reared in the conventional system for each herd except that they were identified at birth and weighted at various intervals. At slaughter, individual pig lungs and snout were examined for lesions of pneumonia and atrophic rhinitis, respectively. Lesions were scored and correlated with growth indicators for each pig. Included in the growth indicators were: average daily gain (growing phase), average daily gain (finishing phase), average daily gain (total), and days to reach 104.5-kg body weight. Additionally, for each pig, scores for lung lesions were correlated to grades for snout lesions. Three correlation coefficients for measurements of pigs within herd B were significant and included days to 104.5-kg body weight and grades for snout lesions, -0.15 (P less than 0.02); average daily gain (finishing) and grades for snout lesions, 0.17 (P less than 0.01); and average daily gain (total) and grades for snout lesions, 0.16 (P less than 0.01). Contrary to findings in other investigations, pigs that attained market weight at the youngest age did not have the lowest score for lung lesions, the lowest grade for snout lesions, or the least extensive or severe lesions. Combining data from all 3 herds, the mean scores for lung lesions and mean grades for snout lesions decreased significantly (P less than 0.05) as the age of pigs at slaughter increased. All other statistical correlations were not significant.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

8.
本研究通过猪圆环病毒2型(Porcine circovirus type 2,PCV2)和猪繁殖与呼吸综合征(Porcine reproductive and respiratory syndrome virus,PRRSV)强毒共感染3周龄健康仔猪来评价其致病性。试验动物随机分为3组,空白对照组(n=3头),PRRSV单独感染组(n=3头),PCV2和PRRSV共感染组(n=6头),从而比较相互之间的差异。通过临床症状、病理学变化、病原学和血清学检查,对二者混合感染仔猪的致病性进行了研究。结果表明PCV2和PRRSV共同感染能引起仔猪断奶后多系统消耗性综合征,表现为淋巴组织肿大、出血,肉芽肿性炎症,坏死性肝炎,仔猪消瘦、生长缓慢等特征性病变;混合感染能加重PRRSV对仔猪引起的间质性肺炎的严重程度。混合感染可以出现支气管肺炎和明显的肝病变,淋巴结多呈界限明显的块状出血等典型病变。  相似文献   

9.
本试验旨在研究饲粮中添加谷氨酰胺(Gln)对断奶仔猪不同阶段生长性能的影响,以及其对脂多糖(LPS)诱导肠道损伤后断奶仔猪血清生化指标和生长性能的影响。选用24头28日龄健康的"杜×长×大"三元杂交断奶仔猪,随机分为3组,每组8个重复,每个重复1头猪。对照组和LPS组饲喂基础饲粮,Gln+LPS组饲喂添加了1%的外源性Gln的基础饲粮;在试验第22、25、28、30天,LPS组和Gln+LPS组腹腔注射100μg/kg BW LPS,对照组则注射相同剂量的生理盐水。试验期30 d。结果表明:1)LPS处理前(试验第1~21天),与对照组相比,Gln+LPS组显著提高了试验第1~7天断奶仔猪的平均日采食量(ADFI)和平均日增重(ADG)(P0.05),显著提高了试验第8~14天和第1~21天断奶仔猪的ADFI(P0.05)。2)LPS处理后(试验第22~30天),对照组断奶仔猪的ADFI、ADG、第30天体重均显著高于LPS组和Gln+LPS组(P0.05),Gln+LPS组断奶仔猪的ADFI、ADG、第30天体重均高于LPS组(P0.05)。3)LPS组断奶仔猪的小肠长度显著低于对照组和Gln+LPS组(P0.05),而对照组和Gln+LPS组之间无显著差异(P0.05)。4)与对照组相比,Gln+LPS组断奶仔猪的血清高密度脂蛋白胆固醇(HDLC)含量和碱性磷酸酶(ALP)活性显著降低(P0.05),而Gln+LPS组与LPS组之间无显著差异(P0.05);Gln+LPS组和LPS组断奶仔猪的血清免疫球蛋白M(Ig M)含量显著提高(P0.05)。由此可见,饲粮中添加1%的Gln能够显著提高仔猪断奶后第1~7天的生长性能,之后效果不明显。饲粮中添加1%的Gln能够调节应激仔猪的血清生化指标,改善其生长性能和小肠长度,从而缓解仔猪断奶应激。  相似文献   

10.
Water intake of weaned piglets from three to seven weeks old   总被引：2，自引：0，他引：2  
One hundred and two large white cross landrace piglets weaned at 21 (+/- 1) days old were randomly allocated to one of two commercial early weaning diets for a four week growth trial. The piglets were housed in groups of between six and 10. After initial moderate restriction the piglets were fed ad libitum. Food intakes and weight gains were recorded weekly. Water consumption of individual pens of piglets was recorded daily. Dietary treatment had no significant effect on mean daily feed intake, daily liveweight gain or food conversion ratio. The relationship between water and food intake, piglet weight and daily gain was examined using regression and multiple regression analyses. Water intake was related to all these parameters, with daily feed intake being the best single predictor of water intake. The relationship was described by the equation: water intake (litres/day) = 0.149 + 3.053 feed intake (kg/day).  相似文献   

11.
本试验旨在研究脂多糖(LPS)诱导仔猪发生炎症反应时肝脏和脾脏炎性细胞因子和lncRNA-47491、lncRNA-49770、lncRNA-51636表达的变化。选取8头21日龄、体重(7.15±0.42)kg的杜×长×大三元杂交断奶仔猪,随机分为对照组、LPS组,每个处理4个重复,每个重复1头猪。预试14 d后,LPS组和对照组腹腔分别注射100μg/kg体重的LPS、生理盐水,4 h后屠宰并取肝脏和脾脏组织样待测。结果表明:与对照组相比,LPS刺激使肝脏和脾脏中炎性细胞因子的mRNA表达量显著上调;LPS诱导的炎症反应中lncRNA-47491、lncRNA-49770和lncRNA-51636的表达量均显著上调;对lncRNA调控的顺式靶标基因的预测结果显示,lncRNA-47491和lncRNA-51636的靶基因有TMEM235、PGS1、TK1等,lncRNA-49770的靶基因有SRRM2、CLDN6、TNFRSF12A等,且这些基因均与炎症相关。综上,lncRNA-47491、lncRNA-49770及lncRNA-51636可能参与了机体的炎症反应,且靶标基因的预测提示其可能发挥不同的调控作用。  相似文献   

12.
为研究不同毒力的PRRSV对仔猪肺脏和外周免疫器官损伤的差异,本实验分别采用PRRSV变异株(HuN4株)和PRRSV经典株(CH-1a株)感染35日龄健康的断奶仔猪,并在感染后0 d、3 d、7 d、10 d和14 d各迫杀3头,检测肺、颌下淋巴结、肠系淋巴结、腹股沟淋巴结、扁桃体和脾脏的病毒载量及病理变化情况,同时检测血清中抗PRRSV的抗体水平。结果表明:感染后3 d肺脏及各免疫器官可检测到病毒,HuN4感染组病毒载量比CH-1a感染组病毒载量高1 000倍;HuN4感染组病毒载量峰值出现在感染后10 d,而CH-1a感染组维持着较低水平的病毒载量。组织病理学检测显示HuN4感染组淋巴结内淋巴细胞显著减少,呈空泡状;CH-1a感染组淋巴结内淋巴细胞轻度减少,呈星隙状。本实验表明HuN4株比CH-1a株对肺和外周免疫器官造成更严重的损伤。  相似文献   

13.
本试验旨在研究在正常与免疫应激条件下添加恩拉霉素对仔猪的作用效果及安全性。将36头21日龄断奶、健康、DLY阉公仔猪随机分为3个处理,每个处理12个重复;分别饲喂基础日粮及在基础日粮中添加5、80 mg/kg恩拉霉素日粮(加药期),21 d后,各组均饲喂基础日粮(停药期),7 d后,每处理随机取出6头仔猪腹腔注射LPS 200μg/kg体重(应激期),剩余6头仔猪腹腔注射等量生理盐水。分别于应激前和应激后2.5 h、3 d采血。结果表明:日粮添加5 mg/kg和80 mg/kg恩拉霉素不同程度提高0～7、8～14、15～21 d和0～21 d仔猪的日增重和采食量,而对饲料增重比无影响;前期添加恩拉霉素组仔猪的生产性能在停药期仍略优于对照组;LPS应激导致仔猪平均日增重和平均日采食量显著下降(P<0.05);加药期添加恩拉霉素可显著提高应激期仔猪平均日采食量(P<0.05)。注射LPS前,各组血清理化指标没有显著差异(P>0.05);注射LPS 2.5 h后,血清丙二醛、皮质醇和IGF-1的含量显著提高(P<0.05);注射LPS3 d后,血清IGF-1浓度显著提高(P<0.01),NO浓度显著降低(P<0.01),皮质醇浓度有提高的趋势(P<0.1);日粮添加恩拉霉素显著降低了血清中IGF-1的浓度(P<0.01),与LPS具有显著互作效应(P<0.05)。  相似文献   

14.
With the aim to extend the present knowledge on possible systemic spreading of Pasteurella multocida in pigs with bronchopneumonia, the occurrence and associated lesions of P. multocida were described by comparing cultural detection, pathological evaluation and in situ hybridization of P. multocida in lungs, hearts and kidneys from cases of porcine bronchopneumonia. P. multocida was cultivated from the lung lesions in 114 out of a total of 148 cases of porcine bronchopneumonia. Among the 114 cases, P. multocida was also cultivated from the pericardial sacs of 40 pigs and the kidneys of seven pigs. Gross lesions and histological findings included a variety of type and stages of bronchopneumonia in connection to the isolation of P. multocida. Furthermore, chronic fibrous pericarditis, interstitial nephritis and a high proportion of lympho-histocytic nephritis were observed. In situ hybridization identified P. multocida in the majority of the lungs, none of the hearts and in half of the kidneys examined. The results show a possible low rate of systemic spreading of P. multocida from lung lesions in pigs with bronchopneumonia.  相似文献   

15.
The purpose of the present study was to evaluate cattle and buffaloes with respiratory disorders, determine the extent of the lesions, and assess prognosis. The results were compared with the findings determined following physical examination and at slaughter. Animals were referred to Veterinary Teaching Hospitals because of inappetance, loss of body condition, cough, dyspnea, and nasal discharges. Ultrasonographically, it was possible to detect bronchopneumonia, consolidation, pleural effusion, pulmonary emphysema, and pleuritis. It was not possible to visualize lesions located deeper within the lungs where peripheral tissue was not affected. Laboratory findings included a neutrophilic leukocytosis, γ-globulinemia, and increased activity of aspartate aminotransferase. A diagnosis of respiratory disease was made on the basis of clinical and ultrasonographic findings and confirmed in 25 cases at slaughter. Bovine ultrasonography appears to be suitable as a screening tool for detection of pathologic lung processes near the pleura. Thoracic ultrasonography allows assessment of the extent and severity of pulmonary changes so that further evaluations can be considered.  相似文献   

16.
Abstract

The aim of the study was to investigate lesions in sows and their piglets kept on two flooring materials – bare concrete and concrete coated with polyurethane containing sand. In total, 13 lactations on concrete and 11 on polyurethane were evaluated. The severity of skin lesions was scored and teat and claw lesions were recorded. The sand-filled coating was rougher compared to the concrete floor. Larger litter sizes were associated with a higher proportion of wounded teats in sows. Only seven of the 230 piglets had no skin lesions. The piglet skin lesions generally healed, since the number of more severe lesions decreased (p<0.001) and the number of less severe lesions (p<0.001) increased over time. Piglet lesions were associated with daily weight gain and litter size. The number of skin lesions on sows and piglets did not differ between animals kept on concrete and polyurethane-covered flooring. However, piglets kept on the latter flooring had more frequent claw lesions. On both types of flooring the majority of the piglets had skin lesions. Piglets had more claw lesions on polyurethane coating due to its roughness. In addition to the possibility of lower weight gains in piglets due to severe lesions, pig skin lesions are themselves a severe welfare problem in this type of housing system.  相似文献   

17.
The influence of some diseases (lesions at slaughter) on daily weight gain and the relation between some mainly non-environmental factors and diseases, weight gain and carcass quality were studied in 12 herds running an all in/all out fattener production. The material consisted of 9800 baconers slaughtered in the period 1975–1977. The piglets were purchased when about 10 weeks old. The number of batches was 60.The investigation showed that 6 of the 12 diseases included in the analyses had a statistically significant influence on daily weight gain: pyaemia, atrophic rhinitis, severe and moderate pneumonia, tail lesion and scabies. The effect varied from a calculated reduction of 60 g in daily weight gain in pigs having atrophic rhinitis to a positive influence of 5 g/day in animals with recorded scabies lesions.It was also found that an increase in weight of marketing piglets would reduce the risk of contracting many diseases and accordingly increase the frequency of healthy animals. It also seemed possible to increase the frequencies of healthy animals by buying quality piglets. Further, quality piglets had a positive relation to weight gain and best paid carcasses (highest quality). Analyses of flock based antiparasitic treatment were inconclusive with regard to weight gain, parasitic hepatitis and scabies.  相似文献   

18.
为研究脂多糖(LPS)刺激后不同时间点断奶仔猪腓肠肌相关microRNA(miRNA)基因的变化规律,试验选取(7.1±0.9)kg杜×长×大断奶仔猪42头,随机分为7个处理组,每个处理6头猪,分别于注射LPS之前(0 h)和注射LPS之后1、2、4、8、12、24 h,屠宰仔猪,取腓肠肌测定相关miRNA的表达。结果表明:与对照组相比,LPS刺激后2 h,miRNA-10b的mRNA表达量显著降低(P<0.01),且于12 h达到峰值;LPS刺激后1 h,miRNA-1和miRNA-206的mRNA表达量均显著降低(P<0.01),但miRNA-133a的mRNA表达量无显著变化(P>0.05)。LPS刺激早期可诱导腓肠肌相关基因miRNA-10b、miRNA-1、miRNA-206的m RNA表达量在不同时间点下调,表明这些miRNA可能参与了肌肉炎症早期相关信号通路的调控。  相似文献   

19.
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20.
Thirty-nine foals with pneumonia were admitted to the Veterinary Medical Teaching Hospital at the University of California, Davis. Corynebacterium equi was recovered from each of them on bacteriologic culture of transtracheal aspiration specimens or lung specimens at necropsy. The foals were divided into 2 groups. Group I consisted of 20 foals that died because of C equi pneumonia and were subsequently necropsied. Group II consisted of 19 foals that were treated and discharged from the hospital. Radiography was performed on all foals. Clinical signs included increased respiratory rate, fever, cough, nasal discharge, increased bronchovesicular sounds over large airways, and wheezing over small airways. Highly significant differences were found in the mean respiratory rate (P less than 0.005) and temperature (P less than 0.001), recorded at admission, between the 2 groups; both factors were higher for group I. Hematology revealed leukocytosis with neutrophilia, monocytosis, and high plasma fibrinogen content in all foals. Significant differences were recorded in the mean total leukocyte count (P less than 0.05), mean neutrophil count (P less than 0.05), mean monocyte count (P less than 0.005), and mean fibrinogen value (P less than 0.05) between the 2 groups; values from group I were higher than those from group II. Although C equi was isolated alone from 25 of the tracheal aspirates and lung specimens, 14 cultures yielded multiple pathogens. At the time of initial examination, all foals had radiographic evidence of pneumonia. Pulmonary consolidation indicative of bronchopneumonia was identified in 31 of the 39 foals.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

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