Nutritional Variations Of Feed Ingredients; Effects Of Lysine Levels On Performance Of Early-Weaned Piglets

This thesis involves two trials. In trial 1, we analyzed the nutritional compositions content of major feed ingredients, and the results showed that nutritional compositions of different batches of feed ingredients exhibit variation. Trial 2 was conducted to study the effects of different dietary lysine level on performance of early-weaned piglets.1. Composition analyses of feed ingredientsComposition analyses of major feed ingredients were conducted in this trial. The number of feed ingredients selected for corn, corn germ meal, DDGS, soybean meal, rapeseed meal, cotton meal, and fish meal were 261,37,28,141,32,15, and 28, respectively. Chemical compositions of all samples were determined by the methods described in the National Standard of PRC. The results revealed that crude protein content of the seven samples averaged 8.12%,18.57%,29.43%,46.61%,37.04%, 43.36%, and 65.13% respectively, with CV 2.83%,5.65%,3.11%,3.14%,2.50%, 4.98%, and 1.79% respectively. Contents of crude ash, calcium, phosphorus also exhibited different degrees of variation. It was concluded that feed ingredients batch to batch vary widely in composition and it is necessary to know the nutrient composition of each ingredient used in feed formulation.2. Effects of different dietary lysine levels on performance of early-weaned pigletsThis trial was conducted to study the effects of different dietary lysine level on performance of early-weaned piglets.240 crossed-bred (Duroc X Landrace X Yorkshine) piglets, weaned at 25 days, weighing an average of 6.74kg, were randomly allocated into three treatments, four replications per treatment,20 piglets per replication (pen). Diets of three levels of total and digestible lysine content were 1.35%,1.42%,1.60% and 1.22%,1.28%,1.50%, respectively. The crude protein and DE of the three diets were 20% and 14.00MJ/kg. The whole trial lasted for 20 days. The results revealed that average daily gain (ADG), average daily feed intake (ADFI) and F/G changed with the elevated lysine levels quadratically. Based on the comprehensive consideration of ADG, ADFI, and F/G, the oppropriate dietary lysine level was 1.42% for total lysine. The optimal dietary total and digestible lysine levels established from regression equations were 1.45%,1.34%, respectively, for highest ADG, and 1.44%,1.32%, respectively, for highest ADFI,1.49%,1.37%, respectively, for lowest F/G..