Influence of maternal alloxan diabetes or insulin injections on fetal glycogen reserves, muscle and liver development of pigs (Sus domesticus).

Pregnant Yorkshire gilts were allotted to three treatment groups during the third trimester of gestation. One group was alloxanized at 70 days of gestation; the second group was injected daily with protamine zinc insulin beginning at 80 days and the third group receiving saline injections served as controls. At 112 days of gestation, the fetuses were delivered alive by hysterectomy, cleaned and weighed. The results showed that intravenous injections of 50 mg of alloxan/kg body weight was enough to cause diabetes in pigs and demonstrated that pigs could withstand severe diabetes during pregnancy. The body weight of the fetal pigs was not significantly altered. There was no impairment of the prenatal muscle development as evidenced by comparable gastrocnemius muscle weight, muscle DNA, RNA, protein, and semitendinosus muscle glycogen concentrations in the three treatment groups. The liver weight and total liver glycogen content were significantly (P<.01) elevated in the progeny of diabetic gilts at 112 days of gestation. The increased liver weight was accompanied by a significant increase in cellularity (DNA), RNA (P<.01) and protein (P<.05), but reduced cell size (protein/DNA) (P<.O1) when compared to the control progeny. The liver RNA/DNA ratio was unaffected by the treatments. The results indicate that the