关键词: 双波长法, 双波长法, 糜子, 直链淀粉, 支链淀粉

Abstract: The study was conducted to evaluat the effects of different lysine levels in low crude protein on the growth performance and serum biochemical parameters of replacement gilts from 70 to 100 kg and 100 to 125 kg. A total of 96 two-line crossbred gilts(Landrace x Large White), with 69.01 kg of average bodv weigh and similar body conditions, were allocated to four groups with four replicates per group. The gilts were fed four digestible lysine levels of diets in low crude protein based on isoenergetic and ideal amino acid pattern. The results showed that average daily gain (ADG) (908.33 g) was hightest and feed/gain (F/G) (2.77) was lowest in trial group 2 of 70~100 kg gilts (P<0.05). The concentration of serum urea nitrogen (UN) in trial group 2 was significantly lower than that in trial group 1 and 4 (P< 0.05), and there was no significant difference than that in trial group 3 (P>0.05), the concentration of INS and IGF-Ⅰincreased,then decreased whth increasing levels of Dlys (P>0.05),the concentration of serum lysine,threonine in trial group 1 were significantly lower than those in group 4 (P< 0.05),the concentration of others serun amino acid decreased,then increased with increasing levels of Dlys(P>0.05).The ADG (863.14 g) was hightest and F/G (3.08) was lowest in trial group 2 of 100~125 kg gilts (P<0.05). The concentration of UN in trial group 3 was significantly lower than that in trial group 1 and 4 (P< 0.05), and there was no significant difference than that in trial group 2 (P>0.05), the concentration of INS in trial group 3 was significantly higher than that in trial group 1 (P< 0.05), and there was no significant difference than that in trial group 2 and 4(P>0.05),the concentration of IGF-Ⅰincreased,then decreased whth increasing levels of Dlys (P>0.05).the concentration of serum lysine in trial group 1 and 2 were significantly lower than those in group 3 and 4 (P< 0.05),the concentration of others serun amino acid decreased,then increased with increasing levels of Dlys(P>0.05). In conclusion，based on low-protein diets with ideal amine acid patter，when the daily total DLys intake were 16.57 g/d and 15.96 g/d（DLys level in the low-protein diets should be 0.66% and 0.60%）respectively,the gilts with BW of 70 to 10 kg and 100 to 125 kg could have the higher growth performance.