Effects of maternal starvation on some blood metabolites, liver glycogen, birth weight and survival of piglets.

Pregnant crossbred sows were assigned to three treatments during the third trimester of gestation for an evaluation of the effects of maternal starvation on fetal development and piglet survival. Two groups of sows were taken off feed (water and trace mineralized salt only) on days 93 and 107 of gestation, respectively; the third group was fed 1.82 kg of complete sow diet/day and served as the control. Litter size, gestation length and pig birth weight in the 7-day and 21-day starvation groups were not different from those in the control group (P less than .05). Liver weight was depressed (P greater than .05) among the 7-day and 21-day progeny. However, liver glycogen concentrations and total liver glycogen were unaffected. Maternal blood glucose decreased to a fasting but steady level, while free fatty acid (FFA) increased in the two starved groups. Blood glucose and FFA at birth were similar for all treatment groups; however, FFA increased in the progeny of sows in the 7-day (P greater than .05) and 21-day (P greater than .01) starvation groups at 48 hr of age. Blood glucose at 48 hr did not vary (P less than .05), but the control progeny showed a faster glucose utilization, suggesting a greater dependence on carbohydrate metabolism than in the progeny of starved dams. Survival rate at 72 hr of age was higher among 21-day (43.8%) and 7-day (37.5%) progeny than among control progeny (8.5%). The increased plasma FFA level observed with fasting in the progeny of starved dams might indicate a shift toward lipid metabolism, which would account for the improved survival observed among the progeny of treated dams.