Review: Validation of transrectal ultrasonography for assessment of corpora lutea characteristics in pregnant sows and its relationship with litter characteristics at birth.
In a recent study published in the December 2017 issue of the Translational Animal Science, researchers found that using transrectal ultrasonography in pregnant sows was a valid method to assess the average corpora lutea (CL) diameter, as well as finding a strong relationship between piglet birth weight (BW) and CL diameter.
Transrectal ultrasonography is a technique that has been widely used for assessing the ovulation rate in sows and has been found to have some success in counting the number of CL present. In addition, there has been research linking the number of CL with specific embryonic characteristics post-mortem. However, this technique has yet to have been used in Western commercial sows during pregnancy. Therefore, the objectives of this study were first to investigate the accuracy of using transrectal ultrasonography to count the number of CL, as well as measure the average diameter in modern crossbred sows during early pregnancy. Second, investigation into the relationship between the CL characteristics when using transrectal ultrasonography and the subsequent litter characteristics at birth.
Experiment one included 45 pregnant multiparous crossbred sows, ranging from 2 to 13 parities. The Second experiment included 100 pregnant multiparous sows, ranging from 2 to 9 parities. It was discovered that transrectal ultrasonography was an accurate method to assess the average CL diameter in sows during early pregnancy. In addition, a strong relationship was observed between the CL diameter measured by transrectal ultrasonography and the average piglet BW.
Researchers from this study have hypothesized that the higher CL size in pregnant sows may relate to higher progesterone concentrations, which ultimately could favor embryonic growth and piglet BW. However, the specific mechanisms leading to the increased birth weight needs further investigation.
To view the full article, “Validation of transrectal ultrasonography for assessment of corpora lutea (CL) characteristics in pregnant sows and its relationship with litter characteristics at birth,” visit Translational Animal Science.