Solis de Los Santos F, Donoghue A M, Venkitanarayanan K, Dirain M L, Reyes-Herrera I, Blore P J, Donoghue D J
Poultry Science Department, University of Arkansas, Fayetteville, AR 72701, USA
Poult Sci. 2008 Apr;87(4):800-4. doi: 10.3382/ps.2007-00280.
Campylobacter is one of the leading causes of human foodborne illness in the United States, and epidemiological evidence indicates that poultry and poultry products are a significant source of human Campylobacter infections. Reducing Campylobacter in the intestinal tract would reduce contamination of poultry products and eggs. Caprylic acid, an 8-carbon medium-chain fatty acid has been shown to be bactericidal against several pathogenic bacteria. It has, however, not been tested in the control of Campylobacter in chickens. Four trials were carried out to evaluate the efficacy of caprylic acid against cecal Campylobacter jejuni colonization in 10-d-old chicks. In the first 2 trials, day-of-hatch chicks (n=40 per trial) were assigned to negative controls (no Campylobacter, no caprylic acid), positive controls (Campylobacter, no caprylic acid), and a low (0.7%) and a high (1.4%) dose of caprylic acid supplemented in regular chick starter feed (n=10 chicks/treatment). Two more trials were carried out to evaluate a wider range of caprylic acid doses on cecal Campylobacter counts, in which day-of-hatch chicks (n=90 per trial) were assigned to 9 treatments: negative controls (no Campylobacter, no caprylic acid) and caprylic acid doses of 0 (positive controls), 0.35, 0.525, 0.7, 0.875, 1.05, 1.225, and 1.4% (n=10 chicks/treatment). Except for the negative controls, chicks were orally gavaged with approximately 1 x 10(6) cfu Campylobacter on d 3. On d 10, cecal contents were collected and Campylobacter concentrations were determined in each trial. In all 4 trials, the 0.7% dose of caprylic acid consistently reduced Campylobacter content counts compared with the positive control. In trials 3 and 4, doses less than 1.05% consistently reduced cecal Campylobacter content in both trials. At the higher doses, caprylic acid reduced feed consumption and body weight, but did not affect feed conversion when compared with the positive controls. These data suggest that low-dose supplementation with caprylic acid in feed may reduce Campylobacter colonization in young chickens.
弯曲杆菌是美国人类食源性疾病的主要病因之一，流行病学证据表明，家禽及家禽产品是人类弯曲杆菌感染的重要来源。减少肠道中的弯曲杆菌数量将降低家禽产品和鸡蛋的污染。辛酸是一种8碳中链脂肪酸，已被证明对多种病原菌具有杀菌作用。然而，尚未对其在控制鸡体内弯曲杆菌方面进行测试。进行了四项试验，以评估辛酸对10日龄雏鸡盲肠空肠弯曲杆菌定植的效果。在前两项试验中，将出壳当天的雏鸡（每项试验n = 40）分为阴性对照组（无弯曲杆菌，无辛酸）、阳性对照组（有弯曲杆菌，无辛酸），以及在常规雏鸡开食料中添加低剂量（0.7%）和高剂量（1.4%）辛酸的组（每组n = 10只雏鸡）。又进行了两项试验，以评估更广泛剂量的辛酸对盲肠弯曲杆菌数量的影响，其中将出壳当天的雏鸡（每项试验n = 90）分为9种处理组：阴性对照组（无弯曲杆菌，无辛酸）和辛酸剂量为0（阳性对照组）、0.35%、0.525%、0.7%、0.875%、1.05%、1.225%和1.4%的组（每组n = 10只雏鸡）。除阴性对照组外，在第3天给雏鸡口服约1×10(6) cfu弯曲杆菌。在第10天，收集盲肠内容物并在每项试验中测定弯曲杆菌浓度。在所有四项试验中，与阳性对照组相比，0.7%剂量的辛酸始终能降低弯曲杆菌含量计数。在试验3和试验4中，剂量低于1.05%在两项试验中均始终能降低盲肠弯曲杆菌含量。在较高剂量下，与阳性对照组相比，辛酸会降低采食量和体重，但不影响饲料转化率。这些数据表明，在饲料中低剂量添加辛酸可能会减少幼鸡体内弯曲杆菌的定植。
