Borie C, Sánchez M L, Navarro C, Ramírez S, Morales M A, Retamales J, Robeson J
Department of Preventive Animal Medicine, College of Veterinary Sciences, University of Chile, Casilla 2, Correo 15, La Granja, Santiago, Chile.
Avian Dis. 2009 Jun;53(2):250-4. doi: 10.1637/8406-071008-Reg.1.
A combination of three different Salmonella-specific bacteriophages (BPs) and one competitive exclusion (CE) product were used to reduce Salmonella Enteritidis (SE) colonization in experimentally infected chickens. Equal numbers of 7-day-old chickens were used in each of three groups: a CE group (treated with CE), a BP group (treated with BP), and a CE-plus-BP group (treated with both products). The CE product was administered via coarse spray at 1 day of age and the cocktail of three BPs was given via spray at 6 days of age using a multiplicity of infection of 10(3) plaque-forming units. All the experimental groups, except a healthy control group, were challenged orally with 2.95 x 10(5) colony-forming units (CFU)/ml of an SE strain at 7 days of age. Seven days postchallenge, the chickens were euthanatized for individual SE detection, quantitative bacteriology, and phage isolation from ceca and an internal organ pool. The qualitative bacteriology demonstrated that the use of the CE product diminished the incidence of SE to 75.7% and the mixture of BPs reduced it to 80%; when CE plus BP were used, the incidence dropped significantly to 38.7% (P < 0.0001), as compared with the infection control group (100%). A significant difference in the incidence was observed between the CE and the CE-plus-BP groups, and the BP and the CE-plus-BP groups (P = 0.0027 and P = 0.0010, respectively). The mean SE cecal count diminished with the use of CE plus BP (1.6 x 10(2) CFU/g, P = 0.0003) compared with the control group (1.56 x 10(5) CFU/g), the CE group (4.23 x 10(3) CFU/g), and the BP group (9.48 x 10(3) CFU/g). On the basis of the present study, it may be concluded that the use of both types of biocontrollers can be an effective method for reducing SE colonization in commercial chickens, but further basic and applied research is needed.
使用三种不同的沙门氏菌特异性噬菌体（BPs）和一种竞争排斥（CE）产品的组合来减少实验感染鸡中肠炎沙门氏菌（SE）的定植。三组中每组使用数量相等的7日龄鸡：CE组（用CE处理）、BP组（用BP处理）和CE加BP组（用两种产品处理）。CE产品在1日龄时通过粗喷雾给药，三种BPs的混合物在6日龄时通过喷雾给药，感染复数为10³ 噬菌斑形成单位。除健康对照组外，所有实验组在7日龄时口服2.95×10⁵ 菌落形成单位（CFU）/ml的一株SE菌株进行攻毒。攻毒后7天，对鸡实施安乐死以进行个体SE检测、定量细菌学分析以及从盲肠和一个内脏器官池中分离噬菌体。定性细菌学分析表明，使用CE产品可将SE的发生率降至75.7%，BPs混合物可将其降至80%；当同时使用CE加BP时，与感染对照组（100%）相比，发生率显著降至38.7%（P < 0.0001）。在CE组和CE加BP组之间以及BP组和CE加BP组之间观察到发生率存在显著差异（分别为P = 0.0027和P = 0.0010）。与对照组（1.56×10⁵ CFU/g）、CE组（4.23×10³ CFU/g）和BP组（9.48×10³ CFU/g）相比，使用CE加BP可使盲肠中SE的平均计数减少（1.6×10² CFU/g，P = 0.0003）。基于本研究，可以得出结论，使用这两种生物控制剂可能是减少商品鸡中SE定植的有效方法，但仍需要进一步的基础研究和应用研究。
