By Madie R. Wensley, Jason C. Woodworth, Joel M. DeRouchey, Mike D. Tokach, Steve S. Dritz, and Robert D. Goodband, Kansas State University; and Keith D. Haydon, CJ American-Bio
Tryptophan is an essential amino acid in swine diets that is important for stimulating feed intake and subsequently, growth performance. Monogastrics cannot naturally synthesize Trp in the body, therefore supplying enough Trp in the diet is crucial to meeting the animal’s protein requirements. Crystalline Trp is a readily available source of Trp that is manufactured for food and feed purposes. However, as the world demand for Trp continues to increase, amino acid suppliers are looking for methods to increase Trp supply while decreasing production costs.
Fermented biomass, a waste product generated from the synthesis of crystalline, or feed-grade, amino acid has been considered a viable option because of its opportunity to decrease manufacturing inputs while still providing an amino acid rich product. Recently, CJ American-Bio has developed a fermented Trp product, TRP Pro, for use in livestock and poultry diets. However, there is limited research available to determine its effectiveness as an amino acid source for growing pigs.
The objective of this study was to determine the effects of TRP Pro compared to crystalline Trp on the growth performance of 25- to 50-pound nursery pigs. A total of 315 barrows (DNA 200 × 400) were used at the Kansas State University Segregated Early Weaning Facility. The experiment began on day 21 post-weaning, at approximately 24.9 pounds and lasted for 21 days. Dietary treatments were corn-soybean meal-based and consisted of a negative control (16% Trp:Lysine ratio), positive control (21% Trp:Lys ratio from crystalline Trp), or diets containing Trp with biomass to provide 21 or 23.5% Trp:Lys ratios. Pigs were weighed and feed disappearance was measured every 7 days to determine average daily gain, average daily feed intake and feed to gain ratio.
For the overall period, from day 0 to 21, pigs fed the 21% Trp:Lys ratio from crystalline Trp or Trp with biomass had increased ADG compared to those fed the negative control diet (Figure 1).
There was no significant difference in overall ADFI (Figure 2); however, when pigs were fed the high Trp biomass diet, there was a numeric decrease in feed intake when compared to the low Trp biomass diet.
While the reason is unknown, this could be a result of an increased standardized ileal digestible Trp:Lys ratio creating an imbalance to other amino acids. Furthermore, pigs fed the 21% Trp:Lys ratio from Trp with biomass had improved F/G compared to the negative control diet (Figure 3).
In summary, TRP Pro appears to be a suitable alternative to crystalline Trp in nursery pig diets, as no difference in performance was observed when pigs were fed the same Trp:Lys ratio from either source.