Kollár Anna, Selymes Kinga, Tóth Gergely, Szekeres Sándor, Dobra Péter Ferenc, Bárdos Krisztina, Ózsvári László, Bata Zsófia, Molnár-Nagy Viviána, Tenk Miklós
Department of Microbiology and Infectious Diseases, University of Veterinary Medicine, Hungária krt. 23-25, 1143 Budapest, Hungary.
National Laboratory of Infectious Animal Diseases, Antimicrobial Resistance, Veterinary Public Health and Food Chain Safety, University of Veterinary Medicine, 1078 Budapest, Hungary.
Pathogens. 2025 Jul 17;14(7):707. doi: 10.3390/pathogens14070707.
Necrotic enteritis, caused by () is a disease present worldwide and causes major economic losses. The re-emergence of the disease, in recent years, is mainly due to the ban of the usage of antibiotics as growth promoters in the EU. The aim of this study was to establish a reliable, robust challenge model. Ross hybrid broilers were divided into randomized groups: a positive and a negative control group, a group receiving antibiotic treatment and three groups fed with assorted feed supplements, all receiving the same basal diet. The birds in the treatment groups were vaccinated twice using a 10-times dose of an Infectious Bursitis live vaccine and the animals were challenged four times with a NetB toxin producing strain. The presence of clinical signs and body weight gain were monitored. At the end of the study necropsy was performed and the gut lesions were scored. During the experiment, clinical signs were absent in the negative control group and in the antibiotic treated group. The other animals displayed diarrhea and feather loss. These symptoms were the most pronounced in the positive control group. The gut lesion scores showed significant differences between the negative and positive control groups, with the former scoring the lowest. Based on these results, the challenge model establishment was successful and in this setup the assessment of the potency of feed additives is also possible.
由()引起的坏死性肠炎是一种在全球范围内存在的疾病,会造成重大经济损失。近年来该疾病的再度出现主要是由于欧盟禁止将抗生素用作生长促进剂。本研究的目的是建立一个可靠、稳健的攻毒模型。罗斯杂交肉鸡被随机分为几组:一个阳性对照组和一个阴性对照组、一个接受抗生素治疗的组以及三个饲喂不同饲料添加剂的组,所有组都接受相同的基础日粮。治疗组的鸡使用10倍剂量的传染性法氏囊炎活疫苗进行两次免疫接种,并用一株产生NetB毒素的菌株对动物进行四次攻毒。监测临床症状的出现情况和体重增加情况。在研究结束时进行剖检并对肠道病变进行评分。在实验过程中,阴性对照组和抗生素治疗组未出现临床症状。其他动物出现腹泻和羽毛脱落。这些症状在阳性对照组中最为明显。肠道病变评分显示阴性和阳性对照组之间存在显著差异,前者得分最低。基于这些结果,攻毒模型的建立是成功 的,并且在此设置下也可以评估饲料添加剂的效力。
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