The causative agent of ileitis, Lawsonia intracellularis, is commonly associated with diarrhea and reduced weight gain in growing pigs. The effect of in-feed probiotics on L. intracellularis infection dynamics was evaluated. In brief, 70 2.5-week-old-pigs were randomly divided into six groups with 10-20 pigs each. All pigs were fed an age appropriate base ration for the duration of the study, which was supplemented with one of three Bacillus strains including B. amyloliquefaciens (T01), B. licheniformis (T02) and B. pumilus (T03). Another group was orally vaccinated with a commercial live L. intracellularis vaccine (VAC) at 3 weeks of age. At 7 weeks of age, T01-LAW, T02-LAW, T03-LAW, VAC-LAW and the POS-CONTROL groups were challenged with L. intracellularis while the NEG-CONTROL pigs were not challenged. All pigs were necropsied 16 days later. By the time of inoculation, all VAC-LAW pigs had seroconverted and at necropsy 10-65% of the pigs in all other challenged groups were also seropositive. The results indicate a successful L. intracellularis challenge with highest bacterial DNA levels in POS-CONTROL pigs, VAC-LAW pigs and T01-LAW pigs. There was a delay in onset of shedding in T02-LAW and T03-LAW groups, which was reflected in less severe macroscopic and microscopic lesions, reduced intralesional L. intracellularis antigen levels and a lower area under the curve for bacterial shedding. Under the study conditions, two of the probiotics tested suppressed L. intracellularis infection. The obtained findings show the potential of probiotics in achieving antibiotic-free control of L. intracellularis.

中文翻译：

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补充短小芽孢杆菌益生菌饲料可减轻胞内劳森菌脱落和损害。

回肠炎的病因是细胞内劳森菌，通常与腹泻和成年猪体重减轻有关。评估了饲料中益生菌对胞内劳森氏菌感染动力学的影响。简而言之，将70只2.5周龄的猪随机分为6组，每组10-20头猪。在研究期间，所有猪均饲喂了适合年龄的基本日粮，并补充了三种芽孢杆菌菌株之一，包括解淀粉芽孢杆菌（T01），地衣芽孢杆菌（T02）和短小芽孢杆菌（T03）。另一组在3周龄时口服了商业活细胞内劳森氏菌疫苗（VAC）。在7周龄时，用细胞内劳森氏菌攻击T01-LAW，T02-LAW，T03-LAW，VAC-LAW和POS-CONTROL组，而未攻击NEG-CONTROL猪。16天后对所有猪进行尸检。到接种时为止，所有VAC-LAW猪均已发生血清转化，尸检时，所有其他受攻击组中的10-65％的猪也呈血清阳性。结果表明，在POS-CONTROL猪，VAC-LAW猪和T01-LAW猪中，细菌内DNA含量最高的细胞内劳森氏菌攻击成功。T02-LAW和T03-LAW组的脱落开始有延迟，这反映在较不严重的宏观和微观病变，病灶内胞内劳森氏菌抗原水平降低和细菌脱落曲线下面积较低的情况下。在研究条件下，测试的两种益生菌可抑制细胞内劳森氏菌感染。获得的发现表明益生菌在实现无胞内劳森氏菌的无抗生素控制方面的潜力。所有VAC-LAW猪都进行了血清转化，尸检时，所有其他受攻击组中有10-65％的猪也呈血清阳性。结果表明，在POS-CONTROL猪，VAC-LAW猪和T01-LAW猪中，细菌内DNA含量最高的细胞内劳森氏菌攻击成功。T02-LAW和T03-LAW组的脱落开始有延迟，这反映在较不严重的宏观和微观病变，病灶内胞内劳森氏菌抗原水平降低和细菌脱落曲线下面积较低的情况下。在研究条件下，测试的两种益生菌可抑制细胞内劳森氏菌感染。获得的发现表明益生菌在实现无胞内劳森氏菌的无抗生素控制方面的潜力。所有VAC-LAW猪都进行了血清转化，尸检时，所有其他受攻击组中有10-65％的猪也呈血清阳性。结果表明，在POS-CONTROL猪，VAC-LAW猪和T01-LAW猪中，细菌内DNA含量最高的细胞内劳森氏菌攻击成功。T02-LAW和T03-LAW组的脱落开始有延迟，这反映在较不严重的宏观和微观病变，病灶内胞内劳森氏菌抗原水平降低和细菌脱落曲线下面积较低的情况下。在研究条件下，测试的两种益生菌可抑制细胞内劳森氏菌感染。获得的发现表明益生菌在实现无胞内劳森氏菌的无抗生素控制方面的潜力。在POS-CONTROL猪，VAC-LAW猪和T01-LAW猪中，细胞内挑战具有最高的细菌DNA水平。T02-LAW和T03-LAW组的脱落开始有延迟，这反映在较不严重的宏观和微观病变，病灶内胞内劳森氏菌抗原水平降低和细菌脱落曲线下面积较低的情况下。在研究条件下，测试的两种益生菌可抑制细胞内劳森氏菌感染。获得的发现表明益生菌在实现无胞内劳森氏菌的无抗生素控制方面的潜力。在POS-CONTROL猪，VAC-LAW猪和T01-LAW猪中，细菌内DNA含量最高的细胞内挑战。T02-LAW和T03-LAW组的脱落开始有延迟，这反映在较不严重的宏观和微观病变，病灶内胞内劳森氏菌抗原水平降低和细菌脱落曲线下面积较低的情况下。在研究条件下，测试的两种益生菌可抑制细胞内劳森氏菌感染。获得的发现表明益生菌在实现无胞内劳森氏菌的无抗生素控制方面的潜力。胞内抗原水平和曲线下面积较小，可用于细菌脱落。在研究条件下，测试的两种益生菌可抑制细胞内劳森氏菌感染。获得的发现表明益生菌在实现无胞内劳森氏菌的无抗生素控制方面的潜力。胞内抗原水平和曲线下面积较小，可用于细菌脱落。在研究条件下，测试的两种益生菌可抑制细胞内劳森氏菌感染。获得的发现表明益生菌在实现无胞内劳森氏菌的无抗生素控制方面的潜力。