Effects of Supplemental Liquid DL-methionine Hydroxy Analog Free Acid in Diet on Growth Performance and Gastrointestinal Functions of Piglets

This study was conducted to determine the effect of dietary supplementation of liquid DL-methionine hydroxy analog free acid (DL-MHA) on growth performance and gastrointestinal conditions of piglets. One hundred and eighty crossbred barrow piglets (Large White${\times}$Landrace, body weight: $12.48{\pm}0.33kg$) were divided into three groups with ten replications of six piglets each. Piglets received DL-MHA in diet at a concentration of 0 (control group), 0.15%, or 0.24%. The results indicated that increasing the standardized ileal digestible (SID) of sulfur amino acids (SAA) to lysine (SID SAA:Lys) ratio by supplementation of DL-MHA tended to increase (quadratic; p<0.10) weight gain and ADG, and showed slightly greater (linear; p<0.10) gain:feed ratio. The pH in the diet and cecum linearly decreased (p<0.01), whereas pH in colon had a quadratic response (p<0.01) with increasing supplementation of DL-MHA. By greater supplementation of DL-MHA, the population of Lactobacillus spp. in rectum was likely to increase (quadratic; p<0.10), but Escherichia coli population in the diet was reduced (quadratic; p<0.05). Acetic acid concentration and total short-chain fatty acids in cecum linearly increased (p<0.05), whereas valeric acid in cecum quadratically increased (p<0.05) with increasing DL-MHA levels. Moreover, the villous height of the jejunum quadratically increased (p<0.01) as the supplementation of DL-MHA was increased. It is concluded that the addition of DL-MHA in diet improved the growth performance and the morphology of gastrointestinal tract of piglets.