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121.
Primary porcine endothelial cells have a limited life span in culture. After four to five passages, they tend to de-differentiate and eventually reach senescence. The aim of this work was to establish immortalized porcine aortic endothelial cell lines (AOCs) to facilitate in vitro studies of different pathological process involving the endothelium. Primary porcine aortic endothelial cells (PAECs) were transfected with a plasmid containing the SV40 genome and selected on the basis of morphological and phenotypical features. Flow cytometry analysis demonstrated uptake of acetylated low density lipoproteins (Ac-LDL) and constitutive expression of SLA class I, CD29, CD31, CD41/61, CD80/86, CD46, SWC3, and LAMP-1 antigens by all analyzed lines and showed little differences to primary cells. The functional similarity between primary and immortalized endothelial cells was demonstrated in a cytotoxicity assay using a human natural killer cell line (NKL) as effector. The AOCs cell lines should be valuable tools for in vitro study of the human immune response against pig endothelial cells. In addition, they would be very useful to gain insight in the pathogenesis of some viral haemorrhagic diseases of pig such as African swine fever (ASF) or classical swine fever (CSF).  相似文献   
122.
We evaluated stillbirth risk factors in two commercial swine farms of the Rio Grande do Sul State (south of Brazil). The study was conducted during 1 month in Farm A and during 2 months in Farm B, both during 1999. Data for all farrowings that occurred during the study period were recorded (101 for Farm A and 373 for Farm B), without interference in the farm management. In Farm A, 39% of all litters born during the period of interest had stillborn piglets and the stillborn risk for piglets was 12%. In Farm B, 25% of all litters had stillborn piglets whereas the stillborn risk was 2%. Variables considered as potential risk factors for stillbirths were: parity (1, 2–3, 4+); breed (purebred or crossbred); sow body-condition (normal or fat); use of oxytocin during parturition (yes or no); obstetric intervention through vaginal palpation (yes or no); farrowing duration (<4 or ≥4 h); mummified fetuses (yes or no); total litter size (<12 or ≥12 piglets); and litter birth weight (<11 or ≥11 kg). All stillborn piglets had their classification validated by necropsy. In multivariable logistic-regressions, the cases were the litters having at least one stillborn piglet. In Farm A, litters having at least 12 pigs and in which oxytocin was used during the parturition had 20.8-times-higher odds of stillborn occurrence. In Farm B, litters from sows having parity ≥4 had 2.2-times-higher odds of stillborn occurrence than litters from parity 2 to 3 females, litters having ≥12 pigs had 2.0-times-higher odds of a stillborn piglet than smaller litters and farrowings in which vaginal palpation was performed had 8.0-times-higher odds. Farrowing room management to minimize stillborn risk should target higher-parity females, large litters and optimization of practices of obstetric interventions.  相似文献   
123.
Tropical Animal Health and Production - The objective of this study was to analyze the correlation between condemnations in slaughterhouses situated in Minas Gerais State and notifications to the...  相似文献   
124.
1. Pharmacokinetics of acetylsalicylic acid (ASA) and sodium salicylate (SS) were assessed following single intravenous (i.v.) and oral administration at doses of 50 mg/kg body weight to chickens and turkeys. Plasma drug concentrations were determined using high-performance liquid chromatography with ultraviolet detection and pharmacokinetic variables were calculated using a non-compartmental model.

2. The mean residence time (MRT) of salicylate (SA) after i.v. administration of SS was 6.08 ± 0.59 and 3.32 ± 0.27 h and after oral administration was 6.95 ± 0.72 and 4.55 ± 0.71 h in chickens and turkeys, respectively. The elimination half-life (T 1/2 e) was shorter in turkeys compared with chickens. The value of body clearance (ClB) was higher in turkeys than in chickens, but the apparent volume of distribution (V ss) was similarly low in both species. The bioavailability of SS was complete and the maximal plasma concentration of SA (C max) after oral administration was 96.93 ± 8.06 and 91.76 ± 9.64 µg/ml, respectively, in chickens and turkeys.

3. The MRT of ASA after iv administration was 0.24 ± 0.08 and 0.24 ± 0.02 h and after oral administration was 0.78 ± 0.25 and 0.59 ± 0.13 h, respectively, in chickens and turkeys. In both species, T 1/2 e was very short, ClB and V ss were similar and markedly higher than those of salicylate. The bioavailability of unchanged ASA was low and C max after oral administration was 6.9 ± 3.6 µg/ml in chickens and 8.6 ± 1.3 µg/ml in turkeys.  相似文献   

125.
Summary

The disposition and urinary excretion of ciprofloxacin (CIP) following intravenous (IV) or intramuscular (IM) administration of 7.5 mg/kg body weight in sheep (n = 5) was studied. The intravenous plasma concentration curve was best described pharmacokinetically by a two‐compartment open model, while the intramuscular administration data fitted better to a one‐compartment open model. Mean elimination half‐lives after IV and IM administration were 72 and 184 minutes, respectively. The absorption of intramuscularly administered CIP in sheep was fast: maximal plasma concentration (Cmax) was reached quickly (tmax 31.93 min) and attained values of 0.69 ± 0.27 mg/l. The bioavailability was 49%. The urinary data showed a significant decrease in the elimination rate constant of CIP when CIP was administered intramuscularly. The other parameters calculated did not display differences between the two routes of administration. The results obtained suggest that when CIP was administered by the IM route in the assayed dose, it was able to maintain serum concentrations above the MIC of most common pathogens over an 8‐hour period.  相似文献   
126.
不同处理玉米的有机物质瘤胃降解率及小肠消化率的研究   总被引:2,自引:1,他引:2  
用3头带瘤胃瘘管的杂种肉牛测定玉米、无机保护剂处理玉米、有机保护剂处理玉米、10%和30%鲜血处理玉米有机物质(OM)和非蛋白质有机物质(NPOM)的瘤胃动态降解率,OM分别为53.03%,43.91%,53.57%,35.73%和38.85%,NPOM分别为53.67%,48.06%,55.72%,39.24%和44.48%。用酶解法(牛小肠液冻干粉(BIF))测得玉米、无机保护剂处理玉米、有机保护剂处理玉米、10%和30%鲜血处理玉米12小时瘤胃非降解OM的消化率分别为74.39%,76.26%,75.54%,77.88%和77.43%,NPOM分别为63.92%,64.78%,64.43%,67.78%和65.00%。  相似文献   
127.
This study used multivariate statistics to identify clusters of animals with similar expected progeny difference (EPD) and also identify leading traits that discriminate between bulls. Various linear selection indices based on specific selection criteria were proposed. Records were collected from 880 young Nelore bulls submitted to performance testing in central Brazil between 2001 and 2012. Pre-weaning average daily gain and weights at 210 days with direct and maternal effects were used in the analysis, in addition to post-weaning weight, scrotal circumference at 365 and 450 days, carcass finish and rib eye area. EPDs were classified into three groups, and the EPD means of two of these groups stood out and were considered important based on principal component analysis that associated higher values of direct EPD of weights, average daily weight gain and scrotal circumference. The EPDs for weight at 210, 365 and 450 days, pre- and post-weaning daily gain and scrotal circumference at 365 and 450 days were major causes of variation. Each linear selection index proposed (SI1, SI2, SI3, SI4 and SI5) defined a specific approach meaning that a different selection index should be used depending on breeding goals and selection criteria.  相似文献   
128.
A total of 229 Spanish Actinobacillus pleuropneumoniae isolates recovered from diseased pigs with pleuropneumonia from 1997 to 2004 was tested for their susceptibility to 11 antimicrobials in a broth microdilution method. All the isolates were susceptible to florfenicol and most of them to cephalothin; however, a high rate of resistance was observed to tetracycline. A bimodal or multimodal distribution of isolates over the MIC range were observed for penicillins, tetracycline, trimethoprim, sulfisoxazole and nalidixic acid, suggesting the development of acquired resistance. Eight resistance patterns were established, and 21.1% of the isolates were resistant to at least two antimicrobials. In addition, a considerable increase in the resistance to tetracyclines was observed during the last decade in Spain, when compared with other A. pleuropneumoniae strains isolated during 1987-1988 (Gutiérrez, C.B., Píriz, S., Vadillo, S., Rodríguez Ferri, E.F., 1993. In vitro susceptibility of Actinobacillus pleuropneumoniae strains to 42 antimicrobial agents. Am. J. Vet. Res. 54, 546-550); this finding was also observed for gentamicin in minor percentage.  相似文献   
129.
A 6-year-old female Alaska Malamute dog was presented for evaluation of abdominal enlargement referred by a local veterinarian. On the history, the owner complained of chronic abdominal enlargement initiated more than 4 months ago, reduced appetite, occasional vomiting and general dullness. He also complained of greenish mucous intermittent vaginal discharge starting 10 days ago. The bitch was chronically treated with medroxiprogesterone acetate. A laparatomy was performed and fluid in the abdomen was found and aspirated during the surgery. Also a very fluid-filled distended uterus and a mass in the distal part of the left uterine horn were found. The mass was encapsulated by the omentum, but areas of necrosis and calcification were identified. Histopathological diagnosis was endometrial adenocarcinoma.  相似文献   
130.
对FC株猪源性肠毒素型大肠杆菌致病因子的研究   总被引:1,自引:0,他引:1  
FC菌株是一株从腹泻仔猪粪便中分离的肠毒素型大肠杆菌(Enterotoxigenic E.coli,ETEC)。在MRHA反应中,本菌能凝集人O型、豚鼠、马、绵羊、牛、鸡和兔的红细胞,对人O型和豚鼠红细胞有很高的血凝性,血抗K88和K99血清不能抑制其对豚鼠和绵羊红细胞的血凝。在体外小肠上皮细胞吸附试验中,本菌对仔猪小肠上皮细胞具有强烈的吸附作用;透射电镜和扫描电镜观察证实了FC株菌除表面具有一种纤毛样结构外,还能定居在仔猪小肠段。血清学试验结果表明,本菌的O抗原属于O101。K88和987P两种抗血清均不能凝集本菌,而K99和F41抗血清均可凝集。对纯化的FC株菌粘着素抗原作等电聚焦和聚丙烯酰胺凝胶电泳分析,结果表明,该菌的粘着素是由等电点分别为4.61和9.78,分子量分别为29500和17500的两种蛋白质抗原所组成。此外,用乳鼠胃内投服试验和兔肠结扎试验证明,该菌只产生热稳定肠毒素。总之,本菌是一株能产生ST的K99,F41的肠毒素型大肠杆菌。  相似文献   
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