This study quantifies the responses of isowean pigs to post-weaning nutritional conditions as may be encountered during extended shipment. PIC breeding stock pigs at 8 to 12 days of age (3.5 to 4.0 kg body weight) were subjected to four nutritional regimens for 72 h. The pigs were then raised with ad libitum feeding for 14 days. Thermoneutral environments were used throughout the experiment. Pigs deprived of feed and water (i.e., Fast) had higher body weight loss (of 0.61 kg/pig or 17% of their initial body weight) as compared with pigs provided with feed and water supplement (0.39 kg/pig or 11% of their initial body weight) or water supplement only (0.43 kg/pig or 11.5% IBW) (P < 0.05). All the treatments led to significant rise in blood urea nitrogen but fall in blood glucose (P < 0.05). However, the glucose levels were much higher than the generally considered hypoglycemic level (75 mg/dL). All pigs showed a similar degree of dehydration, as evidenced by elevated hematocrit and blood electrolyte concentrations (P < 0.05). The physiological responses returned to normal during the 14-day growth period and were similar for all the pigs. The results suggest that isowean pigs (PIC genetic line) responded well to post-weaning nutritional conditions typically encountered during extended shipments. Supply of bacteria-resistant water supplement such as Aqua-Jel seemed beneficial in reducing stress and may be considered for extended commercial shipment. However, in-transit supply of feed added little benefit to the pigs and thus may be omitted. This omission has special implications for international shipments because certain countries prohibit inclusion of feed in shipment. The energetics data of this study may be used to design and operate ventilation systems in transportation and production facilities for the isowean pigs.