The effect of L-carnitine and soybean oil on performance and nitrogen and energy utilization by neonatal and young pigs.

A total of 64 neonatal pigs was used in an experiment to study the effect of L-carnitine and soybean oil on pig performance and N and energy utilization. Pigs were weaned at an average of 3 d of age and individually fed diets that contained dextrose, corn syrup solids, and isolated soy protein for 21 d. Two levels of soybean oil (1.18 or 12.31%) and L-carnitine (0 or 800 ppm) were used in a factorial arrangement of treatments. Diets were formulated to contain the same nutrient content per megacalorie of ME. Total fecal and urine collections were made from d 17 to 21 of the experiment. Pigs were paired within treatments on d 21 and housed in pens until d 63. L-carnitine was lowered to 750 ppm and the soybean oil additions were 1.15 or 13.22% from d 21 to 42 and 2.17 or 14.74% from d 42 to 63. Soybean meal replaced isolated soy protein from d 42 to 63. Analysis of covariance was used with calculated ME intake per day as the covariate. There were no carnitine x soybean oil interactions (P > .05) for any criteria measured. L-carnitine or soybean oil did not (P > .05) affect ADG, grams of gain per megacalorie of ME, ME as a percentage of GE or N retained as a percentage of N consumed. In conclusion, L-carnitine did not improve the utilization of ME in diets that contained high additions of soybean oil, and calories from soybean oil were utilized as effectively as calories from carbohydrate by neonatal and young pigs.