Effect of capsaicin and capsaicin plus DL-methionine hydroxy analog in diet on growth performance and gastrointestinal conditions of nursery pigs

The study was conducted to determine the effect of supplemental capsaicin (CS) or capsaicin plus DL-methionine hydroxy analog (CS+LMA) in diets on growth performance and gastrointestinal conditions of nursery pigs. Seventy-two castrated male piglets (BW 7.79 ± 0.02 kg) were offered diets for 6 weeks as follows: 1) control diet, 2) control diet with capsaicin 2.5 ppm (CS) and 3) control diet with capsaicin 2.5 ppm plus DL-LMA 0.05% (CS+LMA). The dietary treatments did not influence growth performance, gastrointestinal pH and the bacterial population in the caecum (P>0.05). However, in the caecum, number of Lactobacillus spp. tended to increase (P=0.09) and lactic acid concentration was increased (P<0.05) by CS+LMA supplementation. The supplemental CS or CS+LMA increased the villus height (P<0.01), and CS+LMA supplementation increased the crypt depth (P<0.05) in the segment of duodenum compared to the control group. The blood urea nitrogen (BUN) was not influenced by CS or CSLMA supplementations (P>0.05). In conclusion, supplementing CS improved the small intestinal morphology and there were synergistic effects on the duodenal crypt depth and caecal lactic acid when LMA was combined with CS.