Effect of Dietary Supply of Cysteamine on Sites of Digestion, Small Intestinal Amino Acid Disappearance in Growing Goats

Abstract

Tan, Z.L., Tang, S.X., Liao, Y.P., Zhou, C.S., Jiang, H.L., Sun, Z.H., Tayo, G.O., Xiao, W.J. and Chen, F.H. 2008. Effect of dietary supply of cysteamine on sites of digestion, small intestinal amino acid disappearance in growing goats. J. Appl. Anim. Res., 34: 71–76.

Four Liuyang Black growing goats were used to examine the effect of dietary supply of cysteamine (CS) on feed intake, site and extent of digestion and apparent intestinal amino acid (AA) digestibility in a 4x4 Latin square design. The goats were weighed initially at 11.8 kg (SD 1.6), fitted with the permanent ruminal, duodenal and ileal fistulae and fed ad libitum in individual pens. Four treatments consisted of a basal diet only (control) and dietary supply of CS at levels of 20, 40 and 60 mg/kg dry matter, respectively, to the basal diet. The experimental period lasted for 14 d for each treatment. Dietary supply of CS had no effect (P>0.05) on intake of nutrients. Ruminal digestion of ADF and NDF decreased (P=0.01) on higher level of CS supplementation. The small intestinal digestibilities of alanine, methionine, threonine and valine decreased (P<0.05) with the inclusion of CS in the diets. The results imply that CS supplementation did not improve the digestibility and absorption of nutrients in the gastro-intestinal tract of goats.

Keywords:

• Cysteamine
• site and extent of digestion
• amino acid digestibility
• goat