Returns increase in a PRRS-positive farm in the middle of a census increase plus a change of management in the batch farrowing system, from 3 weeks to 1.
The owner contacted us because he has seen a reduction in performance in recent months, although no decline has been identified in any particular parameter. He says that, overall, “the sows are doing worse".
The farm reports a problem of low prolificacy (mean annual live births of 11.91) and low fertility in summer, with a marked increase in acyclic returns.
The veterinarian is called from a new established herd in Brittany because some clinical signs appear on gilts from the two first deliveries introduced in the farm.
There is an unusual increase of the returns-to-oestrus at 31-39 days. The majority are due to sows previously negative to the pregnancy ultrasound testing, and the returns-to-oestrus happened before 42 days.
There was an increase of repetitions in females (at 17-28 days, cyclic and acyclic, with a repeat rate of 22%) and mucous-like, white to brown (chocolate) vulvovaginal discharge hours after artificial insemination.