Abstract: This paper was conducted to study the effect of different dietary lysine levels on apparent digestibility of nutrients and serum amino acid concentration and serum biochemical indexes in the growing pigs. The trial was used the total collection method. 12 cross-bred castrates(Large white Landrace)at about 20 kg BW were randomly allotted to three treatments on the basis of initial weight and size. The three treatments were fed basal diet containing 0.65% lysine, and 0.95% and 1.25% lysine respectively. The trial lasted 10 days. The results indicated that the apparent digestibility of dietary nutrients of treatment Ⅱ was best, in the experimental conditions. Decreasing the dietary lysine level(Treatment Ⅰ)had significantly lower the apparent digestibility of energy, dry matter, crude protein and phosphorus than the other two treatments (P<0.05). The concentrations of serine, glutamic acid, threonine, cysteine, tyrosine and lysine were significantly affected (P<0.05 or P<0.01)by increasing or decreasing dietary lysine levels. Meanwhile, the serum urinary nitrogen(BUN) and total serum protein(TP) contents of growing pigs in treatment Ⅰ were significantly higher and lower than treatment Ⅱ and treatment Ⅲ, respectively(P<0.05), however, there were no significant influence in the concentrations of serum glucose(GLU) and serum triglyceride(TG)of growing pigs(P>0.05). The results suggest that the optimal lysine level in growing pigs(20-35 kg)was 0.95%, in the experimental conditions.

Key words: Lysine, Growing pigs, Apparent nutrient digestibility, Serum amino acid concentration, Serum biochemical indexes

CLC Number: 

• S828.5