The feeding value of vegetable oils for weaning pigs studied a total of 210 pigs (PIC 327 × 1050, initially 13.1 kg BW and 46 days of age) were used in a 21-day trial to evaluate the effect of oil source and level on nursery pig growth performance. The two oil sources included a commercial source of soybean oil (Grain States Soya Inc., West Point, NE), and a proprietary source of refined corn oil originating from the ethanol industry (Corn Oil ONE, LLC Pleasant Hill, IA). Five experimental diets were formulated: a control diet without added oil, diets with 2.5 or 5% added soybean oil, or diets with 2.5 or 5% added corn oil. Soybean oil and corn oil were assigned a NE value of 7,545 and 7,549 kcal/kg, respectively for diet formulation.

Results of this 21-day study indicated no performance differences between oil sources or level interactions. Increasing corn or soybean oil had no effect on average daily gain or final body weight; however, increasing corn oil or soybean oil decreased (linear; P < 0.05) average daily feed intake, which resulted in improved (linear; P < 0.01) feed efficiency. Caloric efficiency (Mcal net energy/kg of gain) was not affected by oil source or level, indicating the energy values assigned to the oil sources were accurate. This study also shows the benefits of adding either corn or soybean oil in late-phase nursery diets to improve feed utilization.