[Obliteration of all teat cisterns in a cow].

A rare case of agalactia in a 7 year old cow is described. At the start of the 5th lactation all the teat cisterns were obliterated. Post mortem x-ray examination, with bariumsulfate contrast deposition in the glandular--and the teat cisterns, showed horizontal membranes in the proximal half of the teat cisterns. The membranes were 13--20 mm thick and consisted of fibrous tissue. Glandular tissue, distal parts of teat cisterns and teat canals were normal, and there was no sign of mastitis Obliteration of the teat cisterns, which had developed during the dry period, between the 4th and 5th lactation periods, were assumed to be a result of improper machine milking. The importance of overmilking is discussed.