Electron microscopic observations on the luminal surface of teat cup liners of milking machines used under South African conditions.

An investigation undertaken with the aid of scanning electron microscopy (SEM) on new and used teat cup liners revealed the generally poor quality of luminal surfaces. Even those of the brand-new distributor controls showed significant faults in the evenness and continuity of the liner surface. A hundred and 500 milkings apparently tend to aggravate faults like cracks, pores, grooves and pits, because of the general brittleness of some of the teat cup liners. The poor quality of the liners investigated raises various questions about the method of distribution of teat cup liners and serious concern about the role they play in predisposing bovine udders to mastitogenic infections, spreading mastitis, affecting the production and quality of milk, increasing the cost of milk production and reducing profits of dairy farming.