The effect of dietary supplementation of pregnant gilts with Gromega lipid supplement (JBSUnited feeds), zinc sulfate, or the two combined on development of specific regions of newborn piglet brains was examined in this experiment. The relationship between development of brain regions, preweaning mortality and neonatal nursing ability was also explored. A simple, rapid and inexpensive assay, the “immunocrit”, was developed and validated as a simple indicator of newborn piglet nursing ability. Results of the experiment indicated a significant but weak association between the degree of development of the brain stem and immunocrit measurements. Combined Gromega and zinc supplementation of gilts increased development of this same region of the piglet brain, but did not improve immunocrit or preweaning survival. The immunocrit assay will be a valuable tool to assess neonatal piglet nursing ability in future experiments to improve this trait in newborn piglets. Although this experiment suggests that combined Gromega and zinc supplementation may be beneficial to neonatal piglet brain development, further research is needed to determine whether this improved brain development results in improvement in preweaning survival of piglets.