Cawthraw S A, Newell D G
Veterinary Laboratories Agency, New Haw, Addlestone, Surrey KT15 3NB, United Kingdom.
Avian Dis. 2010 Mar;54(1):86-93. doi: 10.1637/9004-072709-Reg.1.
The role of maternal antibodies in the lag phase of Campylobacter positivity, widely observed in commercial broiler flocks, was investigated. The results indicate that 3-wk-old birds derived from a commercial flock are more susceptible to colonization with Campylobacter jejuni than 1-to-2-wk-old birds. This increasing susceptibility parallels the loss of maternally derived, circulating, anti-Campylobacter, immunoglobulin Y antibodies as detected by enzyme-linked immunosorbent assay. The role of these antibodies in resistance to colonization was further investigated using progeny from breeder flocks of known Campylobacter status. These results confirmed that maternal antibodies confer partial protection against Campylobacter colonization on young chickens (1-2 wk old). This protection was directed against challenge with both homologous and heterologous strains of C. jejuni and even against strains with a high colonization potential. However, evidence presented indicates that newly hatched chicks, with the highest levels of maternal antibodies, were as susceptible to Campylobacter challenge as 3-wk-old birds. This conundrum was investigated further, and an increase in resistance was detected from 1 to 3 days of age. The reasons for this are, as yet, unknown, but the observation validates the use of newly hatched chicks in models of Campylobacter colonization. Moreover, this high susceptibility in the first few days of life may explain the occasional early flock colonization observed, especially when environmental exposure to Campylobacter is high, for example, in free-range birds.
研究了母源抗体在商业肉鸡群中广泛观察到的弯曲杆菌阳性滞后期的作用。结果表明，来自商业鸡群的3周龄鸡比1至2周龄鸡更容易被空肠弯曲杆菌定植。这种易感性的增加与通过酶联免疫吸附测定法检测到的母源循环抗弯曲杆菌免疫球蛋白Y抗体的丧失平行。使用已知弯曲杆菌状态的种鸡群的后代进一步研究了这些抗体在抵抗定植中的作用。这些结果证实，母源抗体为幼鸡（1至2周龄）提供了部分抗弯曲杆菌定植的保护。这种保护针对空肠弯曲杆菌的同源和异源菌株的攻击，甚至针对具有高定植潜力的菌株。然而，现有证据表明，母源抗体水平最高的新孵化雏鸡与3周龄鸡一样容易受到弯曲杆菌攻击。对此难题进行了进一步研究，发现1至3日龄时抵抗力有所增加。其原因尚不清楚，但这一观察结果验证了在弯曲杆菌定植模型中使用新孵化雏鸡的合理性。此外，生命最初几天的这种高易感性可能解释了偶尔观察到的早期鸡群定植现象，特别是当环境中弯曲杆菌暴露量很高时，例如在放养的鸡中。
