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.
articles about returnsTags
Weaning one or several weeks straight into pens, a week worth of space can be gained
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.
We recommend that producers pay more attention to gilts and sows that are at risk of increasing NPD. Situations of increased risk are described.
The shorter and lower dose regime saves money but there is an increased risk of follicular cyst development, which may occur at doses below 13mg/day.
Meeting batch breeding targets requires availability of enough service-ready weaned sows and gilts.
20 years ago we inseminated gilts when too small, then we inseminated them when too heavy, and now we are returning to an intermediate weight.
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.