Data Pinpoints Sow Dropouts

Sow herd culling and mortality rates continue on the upswing. Although 2001 PigCHAMP recordkeeping data has yet to be summarized, a 12-month snapshot (June 1, 2000 to May 31, 2001) verifies the trend and provides some insight into the reasons sows drop out of the breeding herd.

For the nearly quarter of a million sows with complete parity records represented in the removal analysis, half were culled from the herd during the 12-month period and nearly 8% died (see accompanying table).

Sow removal is tabulated in three broad categories — culled, death or destroyed. Within each category is a menu of reasons sows are removed. Space limitations dictated that only the most prevalent data lines in each category could be presented.

Reasons for Culling

At first glance, it appears that “old age/parity” is the leading reason sows are culled (12.9%). However, a closer look at the reason-for-culling list shows a significant number of sows and gilts, across all parities, failed to get bred or stay pregnant. Specifically, in the report, this would include sows that: aborted (2.8%), did not conceive (10.3%), failed to farrow (1.2%), fertility failure (1%), found not pregnant (1.9%), no heat (7.9%) and pregnancy tested negative (1.7%).

Death & Destroyed

Perhaps more striking is the 12.8% death loss. As recent as 1999, the annual PigCHAMP summary shows death loss at just half that — 6.9%. The cause of death for nearly half of those losses is classified as “other” or “unknown” (1.1% and 5.1%, respectively), so specific answers for these losses cannot be pinpointed.

Lameness and downer sows are the most noted causes of death or need to destroy sows, and in combination, represent 16% of the sows in the analysis.

The analysis also showed that the average parity for sows culled was 3.8, while the average parity of sows that died or were destroyed landed at 2.3.

Gilts and Sows Selected for the Removal Analysis (entered the herd or farrowed) in the Report Period, June 1, 2000 - May 31, 2001