摘要
出生前后的早期营养对动物免疫系统的发育和功能较成年期更为关键,而且早期营养与随后疾病的发生有一定关系。当营养不良时,胎儿或初生动物代谢功能的可塑性使得它们能够适应营养不良而存活,这种适应反应通常表现为生长或淋巴器官发育迟缓和免疫能力降低,而这些表现既使在随后营养条件改善的情况下仍然可以继续保持,早期营养因而可以“预设”动物的免疫系统。为数不多的试验研究表明,断奶后短期蛋白质补饲可以增强绵羊对消化道寄生线虫的长期抵抗力,证明了早期营养对家畜免疫力的“预设”效应,但在早期营养可满足动物维持需要的情况下,这种效应可能不复存在。
Nutrition during perinatal period is more critical for the developme nt of the immune system than during adulthood, and the relationship between earl y nutrition and diseases in later life has been established. In humans and labor atory animals, the plasticity of metabolic function in foetuses or neonates enab les them to adapt to malnutrition for survival; however, such an adaptation, as usually evidenced by retarded growth, stunted development of lymphoid organs and impaired immunocompetence, can maintain and persist into later life even when n utrition is improved. Early nutrition may thus programme' the immune system of a nimals. Limited experimental studies have also revealed that long-term immunity against nematode parasites in sheep can be enhanced by a short-term protein su pplementation shortly after weaning, a form of 'nutritional programming', but su ch an effect appears to vanish if the nutritional status of young animals alread y meets at least the requirement for maintenance.
