奈米微粒對動物生理之影響

Abstract

Nanoparticles are structures sized between 1 to 100 nm. Due to their extremely microscopic size, the value of ratio of activity to weight is enormously high. In other words, nanoparticles have the same or even better efficacy by using relatively much lighter dosages than those of the larger particles under the same condition. So far, nanoparticles have been widely applied in variable aspects, such as inhibition of microbial growth, medical applications, or feed additive of weaning piglets to reduce the population of intestine coliforms and ameliorate food intake and growth performance. Despite the broad applications to the products for daily use, little is known about the impact of nanoparticles on the livestock while the animals are administered the microscopic particles. Recent studies have demonstrated that the nanoparticles could penetrate capillaries and distribute throughout the body, which would affect physiology of animal cells. It has been shown that not only cytotoxicity and immunoreactions, but also the changes of organ weights, cell morphology, serum hormone concentrations and gene expression would be possibly caused by the administration of nanoparticles reached to a certain level. Hence, the further and thorough investigations are required to understand the effects of nanoparticles on the animal health and environment.顆粒大小介於1-100nm時稱之為奈米微粒，由於其體積微小，故活性與重量比相當高。於相同條件下，奈米微粒可較其他大粒子以相對較少之劑量達到相同效果，甚至更為優越。奈米微粒應用範圍廣泛，可應用於抑制微生物生長、醫學用途或作為離乳仔豬飼料添加物，以降低其腸道內總大腸菌(coliform)之數量，並改善離乳仔豬之採食量與生長性能。儘管奈米微粒應用廣泛，然當其使用於禽畜，是否會造成負面影響仍不明瞭。研究指出，奈米微粒可穿過微血管而遍佈於體內，進而影響動物細胞之生理，且其濃度若達一定量，不但具有細胞毒性並可能引起免疫反應，造成動物器官重量、細胞形態、血漿中激素濃度與基因表現之變化。因此，奈米微粒之應用對於動物健康與環境影響之相關資訊，仍需更進一步之深入研究