Evaluation of Amino Acid Imbalances in Corn and Low Protein Diets in Reducing Growth Rate and Feed Intakes in Late Finishing Pigs

The following experiment was designed to compare late finishing pigs fed Corn and Low Protein (LP) diets, which contain added levels of DL- Methionine to create an amino acid imbalance, which results in pigs consuming less feed, and thus reducing growth rates. Four experimental diets were evaluated involving two treatments at the Kent Nutrition Group Research Farm. The first treatment consisted of a diet utilizing Corn along with 18 lb/ton of added DL-Methionine during Days 0-7 with the level of added DL-Methionine increased to 22 lb/ton during Days 7-13. The second treatment consisted of a diet utilizing Low Protein (75 lb/ton of added soybean meal added to the corn) along with 18 lb/ton of added DL-Methionine during Days 0-7 with the level being increased to 22 lb/ton during Days 7-13. Previous Kent research in late finishing pigs (Nutrition Note, May 6, 2020) showed dramatic reductions in growth and feed intake when finishing pigs (initial weight of 273 lb) were fed Corn and LP diets with 33 to 63 lb/ton of added DL-Methionine during the first six days on test. In this current trial, salt was also added to all diets at 15 lb/ton to further add some reduction in performance. The initial starting weight of these pigs was 287 lbs. Most of the pigs in this trial had previously been on diets that varied in added DL-Methionine for 21 days with these pigs being balanced and allotted across the two treatments in the current trial.

Table 1: Experimental Diets

Table 2: Performance of Late Finishing Pigs