Frost A J, Brooker B E
J Comp Pathol. 1983 Apr;93(2):211-8. doi: 10.1016/0021-9975(83)90008-7.
The mammary glands of eight non-lactating dairy cows were infused with either endotoxin or the sterile culture filtrate in which Escherichia coli had been grown (CCF). Animals were necropsied at intervals up to 24 h after infusion. Only mild inflammation of the teat and lactiferous sinuses occurred after 4 h, subsiding gradually to 24 h. After mixing dry cow secretion with either endotoxin or CCF, an intense inflammatory response was produced on inoculation of quarters of a lactating cow; CCF also produced necrosis of the epithelium. Thus, dry gland secretions do not inhibit the effect of filtrate or endotoxin. It was concluded that the refractory nature of the gland to these toxins in the non-lactating animal is due to the changes which occur in the ductular epithelium during involution.
向八头非泌乳奶牛的乳腺中注入内毒素或大肠杆菌生长过的无菌培养滤液（CCF）。在注入后长达24小时的间隔时间对动物进行尸检。注入后4小时仅出现乳头和输乳窦的轻度炎症，并逐渐消退至24小时。将干奶牛分泌物与内毒素或CCF混合后，接种泌乳奶牛的乳腺会产生强烈的炎症反应；CCF还会导致上皮坏死。因此，干乳腺分泌物不会抑制滤液或内毒素的作用。得出的结论是，非泌乳动物乳腺对这些毒素的不应性是由于退化过程中小导管上皮发生的变化所致。
