Draskovic Vladimir, Bosnjak-Neumuller Jasna, Vasiljevic Marko, Petrujkic Branko, Aleksic Nevenka, Kukolj Vladimir, Stanimirovic Zoran
Department of Biology, Faculty of Veterinary Medicine, University of Belgrade, Bul. oslobodjenja 18, 11000 Belgrade, Serbia.
Patent Co. DOO, Vlade Ćetkovića 1a, 24211 Mišićevo, Serbia.
Prev Vet Med. 2018 Mar 1;151:46-51. doi: 10.1016/j.prevetmed.2018.01.002. Epub 2018 Jan 10.
Lawsonia intracellularis is known to cause proliferative enteropathy (PE), one of the economically most important swine diseases with global distribution. Not unlike other enteric diseases, PE is a frequent indication for antibiotic therapy. However, their unjustified use leads to an emerging problem - antimicrobial resistance. Thus, the aim of this research was to assess if a phytogenic additive may replace antibiotics in the control of PE in 144 weaned piglets (72 treated and 72 controls) naturally infected with L. intracellularis. The quantity of L. intracellularis faecal shedding was monitored by real-time polymerase chain reaction (PCR) assay in faecal samples on day 0, 14 and 28, whilst the level of the ileum damage was determined by immunohistochemistry (IHC) assay performed on gut sections. Real-time PCR assay revealed that cycle-threshold (Ct) values in the treatment group increased significantly over time and were higher than in the control. These results indicate that the use of the phytogenic additive decreases the faecal excretion of L. intracellularis both throughout the experiment and in comparison to the control. The expression of the L. intracellularis antigen in IHC assay was lower in treated animals, implying that the additive leads to the decrease in the pathogen quantity in the ileum. Significantly higher feed conversion ratio was recorded in the treatment group. The results indicate that the phytogenic additive may be beneficial in the control of PE, but additional research is necessary to assess its use in various pig categories and define the optimum concentrations.
胞内劳森菌已知可引起增生性肠炎（PE），这是一种在全球范围内分布且在经济上最为重要的猪病之一。与其他肠道疾病一样，PE是抗生素治疗的常见适应症。然而，抗生素的不合理使用导致了一个新出现的问题——抗菌药物耐药性。因此，本研究的目的是评估一种植物源添加剂是否可以替代抗生素来控制144头自然感染胞内劳森菌的断奶仔猪（72头治疗组和72头对照组）的PE。在第0、14和28天，通过实时聚合酶链反应（PCR）检测法监测粪便样本中胞内劳森菌的粪便排出量，同时通过对肠道切片进行免疫组织化学（IHC）检测法来确定回肠损伤程度。实时PCR检测法显示，治疗组的循环阈值（Ct）值随时间显著增加且高于对照组。这些结果表明，在整个实验过程中，与对照组相比，使用植物源添加剂可减少胞内劳森菌的粪便排泄量。在治疗动物中，免疫组织化学检测法中胞内劳森菌抗原的表达较低，这意味着该添加剂可导致回肠中病原体数量减少。治疗组的饲料转化率显著更高。结果表明，植物源添加剂可能对控制PE有益，但需要进一步研究以评估其在不同猪类别中的使用情况并确定最佳浓度。
