Effect of level, source and duration of feeding of supplemental energy in sow diets of metabolic and hormonal traits related to energy utilization in the baby pig.

In each of two trials, 30 sows were assigned to six energy-supplemented diets for 5 (trial 1) or 35 d (trial 2) before farrowing, and the effects on sow milk and pig survival characteristics were examined. Treatments consisted of 1.6 kg/d of a basal diet plus .09, .18 or .27 kg of animal fat/d or .20, .39 or .58 kg of cornstarch/d. Two pigs were killed at birth after blood samples were taken and before suckling. Two pigs per litter were fasted to 24 h and two to 48 h of age. Blood glucose was increased (P less than .05) at birth in pigs from sows fed fat in the 35-d feeding, whereas blood glucose was not different in pigs in the short-term feeding of diets Beta-hydroxybutyrate was highest in blood from pigs in the fat-fed groups after a 48-h fast, which was an indication of increased fat metabolism. Beta-hydroxybutyrate was also higher (P less than .05) after a 24 h fast in livers of pigs from sows fed the highest level of fat in both trials than in livers of pigs from sows fed the same level of cornstarch. There were also treatment differences (P less than .05) in liver glycogen content, oxidation of palmitate to CO2, oxidation of glucose to CO2, number of pigs born dead, birth weight and colostrum total lipids and energy content. No treatment-related differences in levels of FFA, triiodothyronine, thyroxine or glucagon in blood of the offspring were observed.