linky
A recent study conducted at Moredun using aborted bovine foetal tissues, collected from across Scotland, showed that 26% were positive for Neospora caninum.
It's worth reading the article and listening to the linked piece from Landward.
The problem of abortion affects cattle meeting the infection for the first time during pregnancy. The implication, or what I inferred, is that once infected a cow will not abort a second time.
a diagnosis of neospora means that she is unlikely to carry a healthy calf to term
I don't think this is right. What I took from the Moredun article and Landward piece was that a cow that's
already infected with neospora
before conception should
not abort - at least, not due to neospora.
However, all that is moot, in that she is persistently failing to breed successfully. So I would cull her, yes.