[目的]研究烈性噬菌体KM104株对不同血清型鸡源沙门菌雏鸡感染的防治效果.[方法]测定KM104株体外裂解谱及体内安全性,确定攻菌剂量和最佳感染复数(MOI);按噬菌体的不同使用时间、频率和滴度分组,构建白羽蛋鸡3个不同血清型鸡源沙门菌感染防治模型,通过记录试验动物存活数及存活率、生长性能、临床症状及病理变化,测定肛拭子排菌量、脾脏载菌量和脏器系数等指标,综合评价KM104的防治效果.[结果]噬菌体KM104对5个血清型沙门菌的综合裂解率为80.65％(50/62),在体外具有较好的抑菌效果,且对雏鸡无明显致病作用;最佳治疗方式:针对鸡白痢沙门菌、鸡伤寒沙门菌和肠炎沙门菌的治疗剂量分别为7.96×107、1.26 × 104和1.68X 107 PFU/mL,采用连续3 d灌喂高滴度噬菌体的方式雏鸡存活率最高(分别为90％、80％、90％),与攻菌后不处理对照组相比,有效减轻试验雏鸡的临床症状及脏器损伤,增重显著上升(P＜0.05)、肛拭子排菌量、脾脏载菌量及脏器系数显著降低(P＜0.05).[结论]噬菌体KM104对多个血清型致病性沙门菌具有广谱裂解活性,对雏鸡无明显致病作用;攻菌前连续3 d灌喂高滴度KM104的方式对预防雏鸡感染鸡白痢沙门菌、鸡伤寒沙门菌和肠炎沙门菌的效果最佳,可用于沙门菌生防制剂开发.
[Objective]This study was to investigate the preventive and therapeutic effects of lytic phage KM104 strain on Salmonella spp.infection in chickens with different serotypes.[Method]In this experiment the in vitro lysis spectrum and in vivo safety of KM104 strain and the attack dose and the multiplicity of infection were determined.According to the time,frequency and concentration for use of the bacteriophage KM104 strains,the prevention and therapeutic models of Salmonella spp.infection from chickens with three different serotypes in White feather laying hens were constructed.By recording the survival number and survival rate,growth performance,clinical symptoms and pathological changes of test animals and measuring bacterial excretion of anal swab,bacterial load of spleen and organ index,the prevention and therapeutic effect of KM104 was comprehensively evaluated.[Result]The cleavage rate of the bacteriophage KM104 in five serotypes of Salmonella spp.was 80.65％(50/62),invitro it had good bacteriostatic effect and had no obvious pathogenic effect on chickens were found.The best treatment method:The therapeutic doses for Salmonella Pullorum,Salmonella Gallinarum and Salmonella Enteritidis were 7.96 × 107,1.26×104 and 1.68×107PFU/mL,respectively,and the survival rate of chicks was the highest(90％,80％and 90％)by continuous feeding with high titer phage KM104 for 3 days.Compared with the untreated control group,it could effectively alleviate the clinical symptoms and organ damage of experimental chicks,and the weight gain increased significantly(P＜0.05),and the bacterial excretion of anal swab,the bacterial load of spleen and organ index decreased significantly(P＜0.05).[Conclusion]Bacteriophage KM104 had broad-spectrum lytic activity against pathogenic Salmonella spp.of multiple serotypes,and had no obvious pathogenic effect on chickens were found.The method of feeding KM104 with high titer for 3 days before bacteria attack had the best preventive effect on chickens from being infected with Salmonella Pullorum,Salmonella Gallinarum and Salmonella Enteritis,and could thus be used for the development of Salmonella spp.biocontrol preparations.
陈丽英;彭娅婷;严红亚;陈培富;信爱国;李珂
云南省畜牧兽医科学院养禽与禽病研究所,昆明 650224||云南农业大学动物医学院,昆明 650201云南省畜牧兽医科学院养禽与禽病研究所,昆明 650224云南农业大学动物医学院,昆明 650201
畜牧业
噬菌体;裂解谱;沙门菌;鸡
Bacteriophage;lysis spectrum;Salmonella;chicken
《中国畜牧兽医》 2024 (001)
278-291 / 14
云南省专家工作站项目(202105AF150077);云南省"兴滇英才"产业技术领军人才专项项目(YNWR-CYJS-2018-047);广东省科技计划项目(2021B1212030015)
10.16431/j.cnki.1671-7236.2024.01.028
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