December 01, 2019

Interpretive Summary: Reproductive tract scoring in sows

Interpretive Summary: Methods for reproductive tract scoring as a tool for improving sow productivity.

By: Dr. Emily Taylor

Maximizing profitability by optimizing performance is essential for commercial production systems and continues to be a hot topic for researchers. Scientists at Iowa State University evaluated reproductive tract scoring as a tool for improving sow productivity. They used vulva width (VW) prior to puberty as a selection measurement for gilts.

There were 958 prepubertal replacement gilts evaluated at approximately 15 weeks of age. Four different methods were utilized for vulva measurements. They included: digital caliper measurement (mm), visual evaluation and scoring by trained farm personnel (FS), and two methods using scoring tools (method A (VSA) and B (VSB)), which were specifically calibrated from the VW distribution measured on gilts from previous studies.

Gilts achieving their first parity increased with scores for VSA, VSB, and FS, however, these categories did not influence the percentage of gilts achieving their second parity. Litter performance improved over two parities using the VSA scoring system (S, M, or L) for gilts considered to have a medium and large vulvar width when compared to small. Similar results were found when using the VSB scoring. Based on a 5-point system, gilts scored with a 2 to 5 had greater total born and born alive when compared to gilts scored at 1. Moreover, FS scoring (1,2 or 3) provided similar results, increasing total born through 2 parities for gilts having a 2 or 3 score compared to those scored as a 1.

The selection of reproductively superior replacement gilts is challenging, and research for improvements most likely will continue. Overall, the results from this study proved that gilts with a reduced vulva score at 15 weeks of age had a reduction in overall reproductive performance. Vulva scoring could be a valuable tool for identifying gilts with the most significant reproductive potential.

To view the full article, visit Translational Animal Science.