Urbain B, Mast J, Beerens D, N'Guyen T Q, Goddeeris B, Ansay M, Gustin P
Département de Pharmacologie-Pharmacothérapie-Toxicologie, Faculté de Médecine Vétérinaire, Université de Liège, Belgium.
Am J Vet Res. 1999 Sep;60(9):1055-60.
To assess the effects of inhalation of feed flour dust and dustborne endotoxin on respiratory tracts of pigs.
29 healthy Belgian Landrace pigs.
Pigs housed in an environmental chamber were exposed for 6 days to feed flour dust (1 to 15 mg/m3) and dustborne endotoxins (50 to 2,500 ng/m3). Effects were evaluated by measuring albumin concentration, lactate dehydrogenase (LDH) activity, cell composition of nasal lavage (NL) and bronchoalveolar lavage (BAL) fluids and blood, and percentages of CD4+ and CD8+ T lymphocytes in blood and lavage fluids. Dustborne endotoxin was obtained by mixing endotoxins from Escherichia coli (serotype O127:B8) with feed flour before spraying the flour in the environmental chamber.
Exposure did not affect cell composition of NL fluid or blood. Total cell counts of BAL fluids were increased in all groups exposed to dust. Macrophage counts were increased in pigs exposed to inhalable dust concentrations as low as 4.4 mg/m3, and lymphocyte counts were increased in groups exposed to high dust concentrations. Percentages of CD4+ and CD8+ T lymphocytes in blood and lavage fluids were unchanged. In all dust-exposed groups, albumin content of BAL fluid was increased, whereas LDH activity was unaffected. Macrophage and lymphocyte infiltration and edema in the bronchi were identified by light microscopy. Effects attributable to E. coli endotoxin exposure were not identified.
Inhalation of feed flour dust did not affect nasal mucosa but did induce bronchial airway inflammation. Dustborne endotoxins did not have effects attributable to endotoxin alone.
评估吸入饲料粉尘和粉尘携带的内毒素对猪呼吸道的影响。
29头健康的比利时大白猪。
将猪饲养在环境舱中，使其暴露于饲料粉尘（1至15毫克/立方米）和粉尘携带的内毒素（50至2500纳克/立方米）中6天。通过测量白蛋白浓度、乳酸脱氢酶（LDH）活性、鼻腔灌洗液（NL）和支气管肺泡灌洗液（BAL）以及血液中的细胞组成，以及血液和灌洗液中CD4+和CD8+ T淋巴细胞的百分比来评估影响。在将环境舱中喷洒面粉之前，通过将来自大肠杆菌（血清型O127:B8）的内毒素与饲料面粉混合来获得粉尘携带的内毒素。
暴露未影响NL液或血液的细胞组成。所有暴露于粉尘的组中BAL液的总细胞计数均增加。暴露于低至4.4毫克/立方米的可吸入粉尘浓度的猪中巨噬细胞计数增加，而暴露于高粉尘浓度的组中淋巴细胞计数增加。血液和灌洗液中CD4+和CD8+ T淋巴细胞的百分比未改变。在所有暴露于粉尘的组中，BAL液的白蛋白含量增加，而LDH活性未受影响。通过光学显微镜鉴定出支气管中的巨噬细胞和淋巴细胞浸润以及水肿。未发现可归因于大肠杆菌内毒素暴露的影响。
吸入饲料粉尘未影响鼻黏膜，但确实诱发了支气管气道炎症。粉尘携带的内毒素未产生仅归因于内毒素的影响。
