The impact of a negative energy balance on porcine phenotypic and granulosa cell molecular responses

I investigated how energy levels during lactation affect reproductive traits in sows, as well as the molecular mechanisms that regulate follicular development. I focused on mural granulosa cells, which play a key role in providing nutrients and other essential molecules for oocyte development.
I compared young sows with low feed intake to those with normal feed intake during the last week of lactation. The feed-restricted sows showed greater body weight loss and smaller average follicle size. By analyzing their gene expression profiles, I found that energy status mainly regulates granulosa cell development through two key signaling pathways, which control the proliferation and differentiation of mural granulosa cells. In addition to these key genes, other molecules are also involved, either directly or indirectly regulating these genes. 
However, this effect was not observed in multiparous sows. This suggests that body reserves accumulated before lactation can buffer the energy demands of lactation and thus protect follicular development.