Trace minerals, Cu and Zn, play a key role in fetal development, being required for immune system and muscle development. However, little is known about the effects of maternal Cu and Zn nutrition on muscle and immune system development of ruminant offspring. Therefore, the objective of this trial was to evaluate effects of trace mineral source on ewe performance during gestation and epigenetic changes to muscle and immune function of their offspring. Ewes were allocated by body weight to receive: no additional Cu or Zn (CON); Cu and Zn sulfates supplying 300% of NRC requirement (ITM); or Cu and Zn as chelates (MINTREX trace mineral, Novus International) supplying 300% of NRC requirement (MMHAC). Treatments were fed 7 d before conception and through parturition. Following parturition, one lamb from every ewe was weighed and harvested at d 0 of life followed by a second lamb at d 60. Jejunum, longissimus dorsi (LD), and thymus were weighed and sub-sampled from lambs for epigenetic and gene expression measures. Treatment and lamb sex were fixed effects in the model. Lambs harvested on d 0 tended to weigh greater (P < 0.10) when ewes were fed MMHAC compared with ITM. Weight of LD on d 0 tended (P < 0.09) to be greater for lambs from ewes fed MMHAC compared with ITM, with no other differences in organ weights observed on d 0 or d 60. Global histone acetylation tended (P < 0.10) to be greater in LD of lambs from ewes fed MMHAC compared with ITM or CON on d 0. Expression of FoxO3 on d 0 was significantly (P < 0.05) lower in LD of lambs from ewes fed MMHAC and CON compared with ITM. Expression of IκBKB tended (P < 0.09) to be greatest, while TNFα tended (P < 0.09) to be lowest, in jejunal tissue of lambs from ewes fed ITM or MMHAC compared with CON on d 0. Expression of TLR2 tended (P < 0.09) to be greatest in jejunal tissue of lambs from ewes fed CON compared with ITM or MMHAC on d 60. Villi width and muscular thickness tended (P < 0.06) to be lower in jejunum of lambs from ewes fed ITM or MMHAC compared with CON on d 60. These data suggest trace mineral supplementation throughout gestation affects progeny muscle development and immune function.