The Impact Of The Use Of Low Protein Amino Acid Balance Of Diets On Production Performance Of Lactating Sows And Nutrients

The objectives of the study were to investigate the effects of low protein amino acids diets on and performance of and N excretion of the lactating sows.Twenty-four crossbred sows (Landrace×Yorkshire) with similar parity,body weight(BW) and body condition were selected and randomly divided into 4 groups and each group had 6 sows.Each sow brought up 12 piglets and the lactation length was 21 days.Four groups of sows were respectively fed diets with different crude protein(CP) levels(18%,17%,16%and14%),and the latter 3 diets were low CP amino acid balanced diets.The results showed that:(1)Compared with CP 18%diet,CP 17%diet had no effects on average daily feed intake(ADFI),lactation weight loss,and piglet weaning weight(P＞0.05); enhanced the survival rate of piglets weaned by 1%;increased the digestibility of crude protein(CP), ether extract(EE),organic material(OM)(P＜0.05),but had no effects on ash digestibility(P＞0.05); reduced nitrogen(N) excretion by 6.2%(P＞0.05);and decreased plasma urea nitrogen(PUN) content(P＜0.05).(2) Compared with CP 18%diet,CP 16%diet had no effects on average daily feed intake(ADFI),lactation weight loss,piglet weaning weight,and survival rate of piglets weaned(P＞0.05);increased the digestibility of CP,EE,OM(P＜0.05),but had no effects on ash(P＞0.05); reduced N excretion by 18.0%(P＜0.05);and decreased PUN content(P＜0.05).(3) Compared with CP 18%diet,CP 14%diet had no effects on average daily feed intake(ADFI)(P＞0.05);increased lactation weight loss(P＜0.05);reduced piglet weaning weight(P＜0.05);decreased the survival rate of piglets weaned by 1%;had no effects on CP and ash(P＞0.05),but increased the digestibility of EE(P＜0.05);reduced N excretion by 20.8%(P＜0.05);and decreased PUN content(P＜0.05).The results indicate that reducing dietary CP levels by 2 percentage points through amino acid balancing did not affect the performance of sows.