Korean Journal of Agricultural Science (Korean J. Agric. Sci.; KJOAS)
Indexed in KCI (Korea Citation Index), Open Access, Peer Reviewed.
pISSN 2466-2402
eISSN 2466-2410

Efficacy of decreasing levels of tryptophan relative to lysine on the performance and meat quality of finishing pigs



Ahammad GS, Kim IH. 2024. Efficacy of decreasing levels of tryptophan relative to lysine on the performance and meat quality of finishing pigs. Korean Journal of Agricultural Science 51:1-8.

Korean Journal of Agricultural Science (Korean J. Agric. Sci.) 2024 March, Volume 51, Issue 1, pages 1-8. https://doi.org/10.7744/kjoas.510101

Received on 11 August 2023, Revised on 02 September 2023, Accepted on 27 September 2023, Published on 1 March 2024.

Efficacy of decreasing levels of tryptophan relative to lysine on the performance and meat quality of finishing pigs

Golam Sagir Ahammad, In Ho Kim*

Department of Animal Resource and Science, Dankook University, Cheonan 31116, Korea

*Corresponding author: inhokim@dankook.ac.kr


We conducted this research to examine the reducing level of lysine : tryptophan ratios in the diet affected the performance and meat quality of finishing pigs. At the end of the experiment, 144 crossbred finishing pigs (Duroc × [Yorkshire × Landrace]) having an average body weight of 70.6 ± 3.9 kg were randomly assigned to four dietary treatments (9 replications, 4 pigs per pen). The pigs in the 4 treatments were fed diets with different lysine : tryptophan ratios, such as 1 : 0.175, 1 : 0.160, 1 : 0.145, and 1 : 0.130. In considering average daily gain (ADG), average daily feed intake (ADFI), and feed conversion ratio (FCR), the ratio of tryptophan and lysine (Lys : Trp) did not show any significant effect (p > 0.05). Moreover, nutrient digestibility had no significant impact (p > 0.05). However, the decreasing level of tryptophan linearly decreased the back-fat thickness at overall period (p = 0.038) and reduced at week 5 (p = 0.007). Additionally, the lean meat percentage (LMP) showed a tendency to increase at initial (linear effect, p = 0.097) and increased at overall period (linear effect, p = 0.045). Therefore, we suggest that Lys : Trp ratio of 0.130 could enhance the meat quality in finishing pigs.


finishing pig, lysine, meat quality, performance, tryptophan


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Author Information

Golam Sagir Ahammad, https://orcid.org/0000-0002-4182-7763

In Ho Kim, https://orcid.org/0000-0001-6652-2504

Conflicts of interest

No potential conflict of interest relevant to this article was reported.